1
|
Kazarina A, Sarkar S, Thapa S, Heeren L, Kamke A, Ward K, Hartung E, Ran Q, Galliart M, Jumpponen A, Johnson L, Lee STM. Home-field advantage affects the local adaptive interaction between Andropogon gerardii ecotypes and root-associated bacterial communities. Microbiol Spectr 2023; 11:e0020823. [PMID: 37606438 PMCID: PMC10580881 DOI: 10.1128/spectrum.00208-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 07/05/2023] [Indexed: 08/23/2023] Open
Abstract
Due to climate change, drought frequencies and severities are predicted to increase across the United States. Plant responses and adaptation to stresses depend on plant genetic and environmental factors. Understanding the effect of those factors on plant performance is required to predict species' responses to environmental change. We used reciprocal gardens planted with distinct regional ecotypes of the perennial grass Andropogon gerardii adapted to dry, mesic, and wet environments to characterize their rhizosphere communities using 16S rRNA metabarcode sequencing. Even though the local microbial pool was the main driver of these rhizosphere communities, the significant plant ecotypic effect highlighted active microbial recruitment in the rhizosphere, driven by ecotype or plant genetic background. Our data also suggest that ecotypes planted at their homesites were more successful in recruiting rhizosphere community members that were unique to the location. The link between the plants' homesite and the specific local microbes supported the "home field advantage" hypothesis. The unique homesite microbes may represent microbial specialists that are linked to plant stress responses. Furthermore, our data support ecotypic variation in the recruitment of congeneric but distinct bacterial variants, highlighting the nuanced plant ecotype effects on rhizosphere microbiome recruitment. These results improve our understanding of the complex plant host-soil microbe interactions and should facilitate further studies focused on exploring the functional potential of recruited microbes. Our study has the potential to aid in predicting grassland ecosystem responses to climate change and impact restoration management practices to promote grassland sustainability. IMPORTANCE In this study, we used reciprocal gardens located across a steep precipitation gradient to characterize rhizosphere communities of distinct dry, mesic, and wet regional ecotypes of the perennial grass Andropogon gerardii. We used 16S rRNA amplicon sequencing and focused oligotyping analysis and showed that even though location was the main driver of the microbial communities, ecotypes could potentially recruit distinct bacterial populations. We showed that different A. gerardii ecotypes were more successful in overall community recruitment and recruitment of microbes unique to the "home" environment, when growing at their "home site." We found evidence for "home-field advantage" interactions between the host and host-root-associated bacterial communities, and the capability of ecotypes to recruit specialized microbes that were potentially linked to plant stress responses. Our study aids in a better understanding of the factors that affect plant adaptation, improve management strategies, and predict grassland function under the changing climate.
Collapse
Affiliation(s)
- Anna Kazarina
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Soumyadev Sarkar
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Shiva Thapa
- Department of Biology, University of North Carolina, Greensboro, North Carolina, USA
| | - Leah Heeren
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Abgail Kamke
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Kaitlyn Ward
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Eli Hartung
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Qinghong Ran
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Matthew Galliart
- Department of Biological Sciences, Fort Hays State University, Hays, Kansas, USA
| | - Ari Jumpponen
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Loretta Johnson
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| | - Sonny T. M. Lee
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
| |
Collapse
|
2
|
Wang J, Wang C, Wu X, Zhang J, Zhao G, Hou Y, Sun H. Effects of moderate drought extension on bacterial network structure in the rhizosphere soil of Leymus chinensis in semi-arid grasslands. Front Microbiol 2023; 14:1217557. [PMID: 37637130 PMCID: PMC10448527 DOI: 10.3389/fmicb.2023.1217557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 07/24/2023] [Indexed: 08/29/2023] Open
Abstract
Introduction Grasslands are home to complex bacterial communities whose dynamic interactions play a crucial role in organic matter and nutrient cycling. However, there is limited understanding regarding the impact of changes in rainfall amount and the duration of dry intervals on bacterial interactions. Methods To assess the impact of changes in precipitation volume and dry intervals on bacterial co-occurrence networks, we carried out precipitation manipulation experiments in the Eastern Eurasian Steppe of China. Results and Discussion We found that alterations in precipitation and dry intervals did not significantly affect bacterial alpha and beta diversity. However, we observed significant changes in the co-occurrence network structure of bacteria in the rhizosphere ecosystem, with the 12-day dry interval showing the most notable reduction in the number of degrees, edges, and clustering coefficient. Additionally, the study identified putative keystone taxa and observed that the moderately prolonged dry intervals between precipitation events had a major effect on the robustness of bacterial networks. The complexity and stability of the network were found to be positively correlated, and were primarily influenced by soil water content, phosphorous, and aboveground biomass, followed by available phosphorus (AP) and total biomass. These findings have the potential to enhance our comprehension of how bacterial co-occurrence pattern react to variations in dry intervals, by regulating their interactions in water-limited ecosystems. This, in turn, could aid in predicting the impact of precipitation regime alterations on ecosystem nutrient cycling, as well as the feedback between ecosystem processes and global climate change.
Collapse
Affiliation(s)
- Jinlong Wang
- College of Science, Traditional Chinese Medicine Biotechnology Innovation Center in Jilin Province, Beihua University, Jilin, China
| | - Chunjuan Wang
- College of Science, Traditional Chinese Medicine Biotechnology Innovation Center in Jilin Province, Beihua University, Jilin, China
| | - Xuefeng Wu
- Chongqing Institute of Quality and Standardization, Chongqing, China
| | - Jinwei Zhang
- Department of Grassland Science, College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Guiyun Zhao
- College of Science, Traditional Chinese Medicine Biotechnology Innovation Center in Jilin Province, Beihua University, Jilin, China
| | - Yu Hou
- College of Science, Traditional Chinese Medicine Biotechnology Innovation Center in Jilin Province, Beihua University, Jilin, China
| | - Haiming Sun
- College of Science, Traditional Chinese Medicine Biotechnology Innovation Center in Jilin Province, Beihua University, Jilin, China
| |
Collapse
|
3
|
Fajardo A, Gazol A, Meynard PM, Mayr C, Martínez Pastur GJ, Peri PL, Camarero JJ. Climate change-related growth improvements in a wide niche-breadth tree species across contrasting environments. Ann Bot 2023; 131:941-951. [PMID: 36996263 PMCID: PMC10332394 DOI: 10.1093/aob/mcad053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 03/29/2023] [Indexed: 06/19/2023]
Abstract
BACKGROUND AND AIMS The vulnerability and responsiveness of forests to drought are immensely variable across biomes. Intraspecific tree responses to drought in species with wide niche breadths that grow across contrasting climatically environments might provide key information regarding forest resistance and changes in species distribution under climate change. Using a species with an exceptionally wide niche breath, we tested the hypothesis that tree populations thriving in dry environments are more resistant to drought than those growing in moist locations. METHODS We determined temporal trends in tree radial growth of 12 tree populations of Nothofagus antarctica (Nothofagaceae) located across a sharp precipitation gradient (annual precipitation of 500-2000 mm) in Chile and Argentina. Using dendrochronological methods, we fitted generalized additive mixed-effect models to predict the annual basal area increment as a function of year and dryness (De Martonne aridity index). We also measured carbon and oxygen isotope signals (and estimated intrinsic water-use efficiency) to provide potential physiological causes for tree growth responses to drought. KEY RESULTS We found unexpected improvements in growth during 1980-1998 in moist sites, while growth responses in dry sites were mixed. All populations, independent of site moisture, showed an increase in their intrinsic water-use efficiency in recent decades, a tendency that seemed to be explained by an increase in the photosynthetic rate instead of drought-induced stomatal closure, given that δ18O did not change with time. CONCLUSIONS The absence of drought-induced negative effects on tree growth in a tree species with a wide niche breadth is promising because it might relate to the causal mechanisms tree species possess to face ongoing drought events. We suggest that the drought resistance of N. antarctica might be attributable to its low stature and relatively low growth rate.
Collapse
Affiliation(s)
- Alex Fajardo
- Instituto de Investigación Interdisciplinaria (I), Vicerrectoría Académica, Universidad de Talca, Campus Lircay, Talca 3460000, Chile
| | - Antonio Gazol
- Instituto Pirenaico de Ecología (IPE-CSIC), Avda. Montañana 1005, E-50192 Zaragoza, Spain
| | - Paulo Moreno Meynard
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP), Camino Baguales s/n, Coyhaique 5951601, Chile
| | - Christoph Mayr
- Institut für Geographie, Friedrich-Alexander-Universität, Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Guillermo J Martínez Pastur
- Centro Austral de Investigaciones Científicas (CADIC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Houssay 200 (9410) Ushuaia, Tierra del Fuego, Argentina
| | - Pablo L Peri
- Instituto Nacional de Tecnología Agropecuaria (INTA)-CONICET, cc332 (9400) Río Gallegos, Santa Cruz, Argentina
| | - J Julio Camarero
- Instituto Pirenaico de Ecología (IPE-CSIC), Avda. Montañana 1005, E-50192 Zaragoza, Spain
| |
Collapse
|
4
|
Zhang A, Chen S, Chen J, Cui H, Jiang X, Xiao S, Wang J, Gao H, An L, Cardoso P. Shrub and precipitation interactions shape functional diversity of nematode communities on the Qinghai-Tibet Plateau. Glob Chang Biol 2023; 29:2746-2758. [PMID: 36794472 DOI: 10.1111/gcb.16638] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 02/02/2023] [Indexed: 05/31/2023]
Abstract
Land use and climate change alter biodiversity patterns and ecosystem functioning worldwide. Land abandonment with consequent shrub encroachment and changes in precipitation gradients are known factors in global change. Yet, the consequences of interactions between these factors on the functional diversity of belowground communities remain insufficiently explored. Here, we investigated the dominant shrub effects on the functional diversity of soil nematode communities along a precipitation gradient on the Qinghai-Tibet Plateau. We collected three functional traits (life-history C-P value, body mass, and diet) and calculated the functional alpha and beta diversity of nematode communities using kernel density n-dimensional hypervolumes. We found that shrubs did not significantly alter the functional richness and dispersion, but significantly decreased the functional beta diversity of nematode communities in a pattern of functional homogenization. Shrubs benefited nematodes with longer life-history, larger body mass, and higher trophic levels. Moreover, the shrub effects on the functional diversity of nematodes depended strongly on precipitation. Increasing precipitation reversed the effects shrubs have on the functional richness and dispersion from negative to positive but amplified the negative effects shrubs have on functional beta diversity of nematodes. Benefactor shrubs had stronger effects on the functional alpha and beta diversity of nematodes than allelopathic shrubs along a precipitation gradient. A piecewise structural equation model showed that shrubs and its interactions with precipitation indirectly increased the functional richness and dispersion through plant biomass and soil total nitrogen, whereas it directly decreased the functional beta diversity. Our study reveals the expected changes in soil nematode functional diversity following shrub encroachment and precipitation, advancing our understanding of global climate change on nematode communities on the Qinghai-Tibet Plateau.
Collapse
Affiliation(s)
- Anning Zhang
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, Gansu, China
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Shuyan Chen
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Jingwei Chen
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, Gansu, China
| | - Hanwen Cui
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, Gansu, China
| | - Xiaoxuan Jiang
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, Gansu, China
| | - Sa Xiao
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, Gansu, China
| | - Jiajia Wang
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Haining Gao
- College of Life Science and Engineering, Hexi University, Zhangye, Gansu, China
| | - Lizhe An
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China
| | - Pedro Cardoso
- Laboratory for Integrative Biodiversity Research, Finnish Museum of Natural History Luomus, Helsinki, Finland
| |
Collapse
|
5
|
Weithmann G, Schuldt B, Link RM, Heil D, Hoeber S, John H, Müller-Haubold H, Schüller LM, Schumann K, Leuschner C. Leaf trait modification in European beech trees in response to climatic and edaphic drought. Plant Biol (Stuttg) 2022; 24:1272-1286. [PMID: 34854183 DOI: 10.1111/plb.13366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/07/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
Leaf morphological and physiological traits control the carbon and water relations of mature trees and are determinants of drought tolerance, but it is not well understood how they are modified in response to water deficits. We analysed five sun-canopy leaf traits (mean leaf size (LS), specific leaf area (SLA), Huber value (HV), water potential at turgor loss point (Ψtlp ) and foliar carbon isotope signature (δ13 C)) in European beech (Fagus sylvatica L.) across three precipitation gradients sampled in moist (2010), dry (2019) and very dry (2018) summers, and tested their response to short-term water deficits (climatic water balance (CWB) preceding sample collection) and long-term water availability (mean annual precipitation (MAP), plant-available soil water capacity (AWC) and neighbourhood competition). Across the 34 sites, LS varied seven-fold (3.9-27.0 cm2 ), SLA four-fold (77.1-306.9 cm²·g-1 ) and HV six-fold (1.0-6.65 cm2 ·m-2 ). In the 2018 dataset, LS showed a negative and HV a positive relationship to MAP, which contradicts relations found in multi-species samples. Average Ψtlp ranged from -1.90 to -2.62 MPa and decreased across the sites with decreasing CWB in the month prior to measurement, as well as with decreasing MAP and AWC in 2019. Studied leaf traits varied considerably between years, suggesting that mast fruiting and the severe 2018 drought caused the formation of smaller leaves. We conclude that sun-canopy leaf traits of European beech exhibit considerable plasticity in response to climatic and edaphic aridity, and that osmotic adjustment may be an important element in the drought response strategy of this anisohydric tree species.
Collapse
Affiliation(s)
- G Weithmann
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - B Schuldt
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - R M Link
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - D Heil
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - S Hoeber
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - H John
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - H Müller-Haubold
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - L-M Schüller
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - K Schumann
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - C Leuschner
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
- Centre for Biodiversity and Sustainable Land Use (CBL), University of Göttingen, Göttingen, Germany
| |
Collapse
|
6
|
Zhao P, Li X, Ran R, Sun H, Zhao J, Chen G. Precipitation and local environment shape the geographic variation of seed size across natural populations of sand rice (Agriophyllum squarrosum). J Exp Bot 2022; 73:5682-5697. [PMID: 35603725 PMCID: PMC9467651 DOI: 10.1093/jxb/erac231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 05/20/2022] [Indexed: 06/15/2023]
Abstract
Sand rice (Agriophyllum squarrosum) is widely distributed on dunes in the Asian interior arid zone, and its large intraspecific trait variation makes it a very good model for investigating the ecological processes underlying its adaptation to the desert environment. In this study, seed size variation across 68 natural populations was used to establish geographic patterns and to quantify the effects of the climate, soil, and collection-year weather variables. The length of the seed major axis and thousand seed weight (TSW) both showed significant longitudinal patterns. Long-term climate variables accounted for most of the explained variances for seed major axis (57.20%) and TSW (91.54%). Specifically, annual precipitation and minimum monthly precipitation had the most significantly positive and negative effects, indicating that longitudinal clines are driven by a precipitation gradient across the species' distribution range. A substantial unique effect of soil variables (27.27%) was found for seed major axis variation, but only 3.64% of TSW variation was explained by soil variables. Two extreme groups were selected to evaluate the genetic and plastic effects on seed size in a common garden experiment. Large-seeded individuals were more competitive in semi-arid regions, and had stronger adaptive plasticity as well as better performance in early seedling establishment, and hence they have potential for use in future domestication projects.
Collapse
Affiliation(s)
| | - Xiaofeng Li
- Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Ruilan Ran
- Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Hong Sun
- Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Jiecai Zhao
- Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, P.R. China
- Shapotou Desert Research and Experiment Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, P.R. China
| | | |
Collapse
|
7
|
Dea HI, Urban A, Kazarina A, Houseman GR, Thomas SG, Loecke T, Greer MJ, Platt TG, Lee S, Jumpponen A. Precipitation, Not Land Use, Primarily Determines the Composition of Both Plant and Phyllosphere Fungal Communities. Front Fungal Biol 2022; 3:805225. [PMID: 37746168 PMCID: PMC10512219 DOI: 10.3389/ffunb.2022.805225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 06/10/2022] [Indexed: 09/26/2023]
Abstract
Plant communities and fungi inhabiting their phyllospheres change along precipitation gradients and often respond to changes in land use. Many studies have focused on the changes in foliar fungal communities on specific plant species, however, few have addressed the association between whole plant communities and their phyllosphere fungi. We sampled plant communities and associated phyllosphere fungal communities in native prairie remnants and post-agricultural sites across the steep precipitation gradient in the central plains in Kansas, USA. Plant community cover data and MiSeq ITS2 metabarcode data of the phyllosphere fungal communities indicated that both plant and fungal community composition respond strongly to mean annual precipitation (MAP), but less so to land use (native prairie remnants vs. post-agricultural sites). However, plant and fungal diversity were greater in the native remnant prairies than in post-agricultural sites. Overall, both plant and fungal diversity increased with MAP and the communities in the arid and mesic parts of the gradient were distinct. Analyses of the linkages between plant and fungal communities (Mantel and Procrustes tests) identified strong correlations between the composition of the two. However, despite the strong correlations, regression models with plant richness, diversity, or composition (ordination axis scores) and land use as explanatory variables for fungal diversity and evenness did not improve the models compared to those with precipitation and land use (ΔAIC < 2), even though the explanatory power of some plant variables was greater than that of MAP as measured by R2. Indicator taxon analyses suggest that grass species are the primary taxa that differ in the plant communities. Similar analyses of the phyllosphere fungi indicated that many plant pathogens are disproportionately abundant either in the arid or mesic environments. Although decoupling the drivers of fungal communities and their composition - whether abiotic or host-dependent - remains a challenge, our study highlights the distinct community responses to precipitation and the tight tracking of the plant communities by their associated fungal symbionts.
Collapse
Affiliation(s)
- Hannah I. Dea
- Division of Biology, Kansas State University, Manhattan, KS, United States
| | - Abigail Urban
- Department of Biological Sciences, Wichita State University, Wichita, KS, United States
| | - Anna Kazarina
- Division of Biology, Kansas State University, Manhattan, KS, United States
| | - Gregory R. Houseman
- Department of Biological Sciences, Wichita State University, Wichita, KS, United States
| | - Samantha G. Thomas
- Kansas Biological Survey and Center for Ecological Research, University of Kansas, Lawrence, KS, United States
| | - Terry Loecke
- Kansas Biological Survey and Center for Ecological Research, University of Kansas, Lawrence, KS, United States
- Environmental Studies Program, University of Kansas, Lawrence, KS, United States
| | - Mitchell J. Greer
- Department of Agriculture and Nutrition Science, Southern Utah University, Cedar City, UT, United States
| | - Thomas G. Platt
- Division of Biology, Kansas State University, Manhattan, KS, United States
| | - Sonny Lee
- Division of Biology, Kansas State University, Manhattan, KS, United States
| | - Ari Jumpponen
- Division of Biology, Kansas State University, Manhattan, KS, United States
| |
Collapse
|
8
|
Jiang M, Bu CF, Guo Q, Ju MC, Pang JW, Mo QX, Wang HM. [Effects of biological crusts on soil organic carbon in sandlands under a precipitation gradient]. Ying Yong Sheng Tai Xue Bao 2022; 33:1764-1772. [PMID: 36052778 DOI: 10.13287/j.1001-9332.202207.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Biological crusts (Biocrusts) are important surface active coverings in arid and semi-arid regions, which affect the content of soil organic carbon (SOC), SOC labile fractions and stability of SOC through photosynthetic carbon fixation. At present, studies on the variation characteristics of SOC, SOC labile fractions and the stability of SOC in biocrusts are rather limited. In this study, two types of typical biocrusts (moss crusts and algae crusts) were selected along a precipitation gradient from northwest to southeast in the Mu Us Sandland (straight line distance 188 km) by measuring soil organic carbon (SOC), soil microbial biomass carbon (MBC), water soluble carbon (DOC), particulate carbon (POC), easily oxidizable carbon (ROC). We aimed to explore the effects of biocrusts on the stability of SOC and carbon decomposition across the precipitation gradient. Results showed that:1) Two types of biocrusts significantly increased the contents of SOC, MBC, DOC, POC, ROC and stability of SOC. Moss crusts increased SOC contents by 1.6 to 2.6 times as that of algae crusts. 2) The lowest SOC contents of the two types of biocrusts were 6.43 g·kg-1 and 14.50 g·kg-1 respectively, which showed an increasing trend with increasing precipitation along the gradient. 3) With the increases of precipitation, the decomposition time of moss litters gradually decreased. The decomposition coefficient of moss litters during the study period (From July to Feb-ruary of the next year) ranged from 0.010 to 0.014, which was significantly lower than that of vascular plants. The carbon release of moss litters from northwest to southeast was 8.09, 10.89, 12.88 g·kg-1, respectively. 4) Results of canonical correspondence analysis showed that water vapor partial pressure, actual evapotranspiration, annual average temperature, subsurface short-wave radiation, potential evapotranspiration and vapor pressure difference were the key climate factors affecting the content of SOC and its active components. Silt content was the main soil factor affecting the content of SOC and its active components.
Collapse
Affiliation(s)
- Man Jiang
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Chong-Feng Bu
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China
- Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, Shaanxi, China
| | - Qi Guo
- Beifang Investigation, Design and Research Co. Ltd., Tianjin 300200, China
| | - Meng-Chen Ju
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Jing-Wen Pang
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Qiu-Xia Mo
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - He-Ming Wang
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China
| |
Collapse
|
9
|
Wang R, Yang J, Liu H, Sardans J, Zhang Y, Wang X, Wei C, Lü X, Dijkstra FA, Jiang Y, Han X, Peñuelas J. Nitrogen enrichment buffers phosphorus limitation by mobilizing mineral-bound soil phosphorus in grasslands. Ecology 2021; 103:e3616. [PMID: 34923633 DOI: 10.1002/ecy.3616] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 09/29/2021] [Accepted: 10/15/2021] [Indexed: 11/11/2022]
Abstract
Phosphorus (P) limitation is expected to increase due to nitrogen (N)-induced terrestrial eutrophication, although most soils contain large P pools immobilized in minerals (Pi ) and organic matter (Po ). Here we assessed whether transformations of these P pools can increase plant available pools alleviating P limitation under enhanced N availability. The mechanisms underlying these possible transformations were explored by combining results from a 10-year field N-addition experiment and a 3700-km transect covering wide ranges in soil pH, soil N, aridity, leaching, and weathering that can affect soil P status in grasslands. Nitrogen addition promoted dissolution of immobile Pi (mainly Ca-bound recalcitrant P) to more available forms of Pi (including Al- and Fe-bound P fractions and Olsen P) by decreasing soil pH from 7.6 to 4.7, but did not affect Po . Soil total P declined by 10% from 385 ± 6.8 to 346 ± 9.5 mg kg-1 , while available-P increased by 546% from 3.5 ± 0.3 to 22.6 ± 2.4 mg kg-1 after 10-year N addition, associated with an increase in Pi mobilization, plant uptake, and leaching. Similar to the N-addition experiment, the drop in soil pH from 7.5 to 5.6 and increase in soil N concentration along the grassland transect were associated with an increased ratio between relatively mobile Pi and immobile Pi . Our results provide a new mechanistic understanding of the important role of soil Pi mobilization in maintaining plant P supply and accelerating biogeochemical P cycles under anthropogenic N enrichment. This mobilization process temporarily buffers ecosystem P-limitation or even causes P eutrophication but will extensively deplete soil P pools in the long run. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Ruzhen Wang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China.,Erguna Forest-Steppe Ecotone Ecosystem Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Junjie Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Heyong Liu
- Erguna Forest-Steppe Ecotone Ecosystem Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Jordi Sardans
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra, Catalonia, Spain.,CREAF, Cerdanyola del Vallès, Catalonia, Spain
| | - Yunhai Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Xiaobo Wang
- Erguna Forest-Steppe Ecotone Ecosystem Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Cunzheng Wei
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Xiaotao Lü
- Erguna Forest-Steppe Ecotone Ecosystem Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Feike A Dijkstra
- Sydney Institute of Agriculture, School of Life and Environmental Sciences, The University of Sydney, Camden, New South Wales, Australia
| | - Yong Jiang
- Erguna Forest-Steppe Ecotone Ecosystem Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Xingguo Han
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China.,College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Josep Peñuelas
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra, Catalonia, Spain.,CREAF, Cerdanyola del Vallès, Catalonia, Spain
| |
Collapse
|
10
|
Fuchs S, Leuschner C, Mathias Link R, Schuldt B. Hydraulic variability of three temperate broadleaf tree species along a water availability gradient in central Europe. New Phytol 2021; 231:1387-1400. [PMID: 33964029 DOI: 10.1111/nph.17448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 05/01/2021] [Indexed: 06/12/2023]
Abstract
Plant hydraulic traits are key for understanding and predicting tree drought responses. Information about the degree of the traits' intra-specific variability may guide the selection of drought-resistant genotypes and is crucial for trait-based modelling approaches. For the three temperate minor broadleaf tree species Acer platanoides, Carpinus betulus and Tilia cordata, we measured xylem embolism resistance (P50 ), leaf turgor loss point (PTLP ), specific hydraulic conductivity (KS ), Huber values (HVs), and hydraulic safety margins in adult trees across a precipitation gradient. We further quantified trait variability on different organizational levels (inter-specific to within-canopy variation), and analysed its relationship to climatic and soil water availability. Although we observed a certain intra-specific trait variability (ITV) in safety-related traits (P50 , PTLP ) with higher within-tree and between-tree than between populations variability, the magnitude was small compared to inter-specific differences, which explained 78.4% and 58.3% of the variance in P50 and PTLP , respectively. In contrast, efficiency-related traits (KS , HV) showed a high ITV both within populations and within the crowns of single trees. Surprisingly, the observed ITV of all traits was neither driven by climatic nor soil water availability. In conclusion, the high degree of conservatism in safety-related traits highlights their potential for trait-based modelling approaches.
Collapse
Affiliation(s)
- Sebastian Fuchs
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
| | - Christoph Leuschner
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
- Centre for Biodiversity and Sustainable Land Use (CBL), University of Goettingen, Goettingen, 37075, Germany
| | - Roman Mathias Link
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
| | - Bernhard Schuldt
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen, 37073, Germany
| |
Collapse
|
11
|
Hu Y, Zuo X, Yue P, Zhao S, Guo X, Li X, Medina-Roldán E. Increased Precipitation Shapes Relationship between Biochemical and Functional Traits of Stipa glareosa in Grass-Dominated Rather than Shrub-Dominated Community in a Desert Steppe. Plants (Basel) 2020; 9:plants9111463. [PMID: 33138183 PMCID: PMC7692965 DOI: 10.3390/plants9111463] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/14/2020] [Accepted: 10/26/2020] [Indexed: 11/16/2022]
Abstract
Understanding the effects of precipitation variations on plant biochemical and functional traits is crucial to predict plant adaptation to future climate changes. The dominant species, Stipa glareosa, plays an important role in maintaining the structure and function of plant communities in the desert steppe, Inner Mongolia. However, little is known about how altered precipitation affects biochemical and functional traits of S. glareosa in different communities in the desert steppe. Here, we examined the responses of biochemical and functional traits of S. glareosa in shrub- and grass-dominated communities to experimentally increased precipitation (control, +20%, +40%, and +60%). We found that +40% and +60% increased plant height and leaf dry matter content (LDMC) and decreased specific leaf area (SLA) of S. glareosa in grass community. For biochemical traits in grass community, +60% decreased the contents of protein and chlorophyll b (Cb), while +40% increased the relative electrical conductivity and superoxide dismutase. Additionally, +20% increased LDMC and malondialaenyde, and decreased SLA and protein in shrub community. Chlorophyll a, Cb, carotenoids, protein and superoxide dismutase in the grass community differed with shrub community, while +60% caused differences in SLA, LDMC, leaf carbon content, malondialaenyde and peroxidase between two communities. The positive or negative linear patterns were observed between different functional and biochemical traits in grass- rather than shrub-community. Soil water content explained changes in some biochemical traits in the grass community, but not for functional traits. These results suggest that increased precipitation can affect functional traits of S. glareosa in the grass community by altering biochemical traits caused by soil water content. The biochemical and functional traits of S. glareosa were more sensitive to extreme precipitation in grass- than shrub-community in the desert steppe. Our study highlights the important differences in adaptive strategies of S. glareosa in different plant communities at the same site to precipitation changes.
Collapse
Affiliation(s)
- Ya Hu
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China; (Y.H.); (P.Y.); (S.Z.); (X.G.); (X.L.)
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoan Zuo
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China; (Y.H.); (P.Y.); (S.Z.); (X.G.); (X.L.)
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China
- Correspondence: ; Tel.: +86-139-1931-6226
| | - Ping Yue
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China; (Y.H.); (P.Y.); (S.Z.); (X.G.); (X.L.)
| | - Shenglong Zhao
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China; (Y.H.); (P.Y.); (S.Z.); (X.G.); (X.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinxin Guo
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China; (Y.H.); (P.Y.); (S.Z.); (X.G.); (X.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiangyun Li
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China; (Y.H.); (P.Y.); (S.Z.); (X.G.); (X.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Eduardo Medina-Roldán
- Department of Health and Environmental Science, Xi’an Jiaotong-Liverpool University, Suzhou 215000, China;
| |
Collapse
|
12
|
Kim JH, Jobbágy EG, Richter DD, Trumbore SE, Jackson RB. Agricultural acceleration of soil carbonate weathering. Glob Chang Biol 2020; 26:5988-6002. [PMID: 32511819 DOI: 10.1111/gcb.15207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 05/20/2020] [Indexed: 05/26/2023]
Abstract
Soil carbonates (i.e., soil inorganic carbon or SIC) represent more than a quarter of the terrestrial carbon pool and are often considered to be relatively stable, with fluxes significant only on geologic timescales. However, given the importance of climatic water balance on SIC accumulation, we tested the hypothesis that increased soil water storage and transport resulting from cultivation may enhance dissolution of SIC, altering their local stock at decadal timescales. We compared SIC storage to 7.3 m depth in eight sites, each having paired plots of native vegetation and rain-fed croplands, and half the sites having additional irrigated cropland plots. Rain-fed and irrigated croplands had 328 and 730 Mg C/ha less SIC storage, respectively, compared to their native vegetation (grassland or woodland) pairs, and irrigated croplands had 402 Mg C/ha less than their rain-fed pairs (p < .0001). SIC contents were negatively correlated with estimated groundwater recharge, suggesting that dissolution and leaching may be responsible for SIC losses observed. Under croplands, the remaining SIC had more modern radiocarbon and a δ13 C composition that was closer to crop inputs than under native vegetation, suggesting that cultivation has led to faster turnover and incorporation of recent crop carbon into the SIC pool (p < .0001). The losses occurred just 30-100 years after land-use changes, indicating SIC stocks that were stable for millennia can rapidly adjust to increased soil water flows. Large SIC losses (194-242 Mg C/ha) also occurred below 4.9 m deep under irrigated croplands, with SIC losses lagging behind the downward-advancing wetting front by ~30 years, suggesting that even deep SIC were affected. These observations suggest that the vertical distribution of SIC in dry ecosystems is dynamic on decadal timescales, highlighting its potential role as a carbon sink or source to be examined in the context of land use and climate change.
Collapse
Affiliation(s)
- John H Kim
- Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Esteban G Jobbágy
- Grupo de Estudios Ambientales, IMASL, Universidad Nacional de San Luis/CONICET, San Luis, Argentina
| | - Daniel D Richter
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | | | - Robert B Jackson
- School of Earth, Energy, and Environmental Sciences, Stanford University, Stanford, CA, USA
| |
Collapse
|
13
|
Fajardo A, Martínez-Pérez C, Cervantes-Alcayde MA, Olson ME. Stem length, not climate, controls vessel diameter in two trees species across a sharp precipitation gradient. New Phytol 2020; 225:2347-2355. [PMID: 31657018 DOI: 10.1111/nph.16287] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 10/23/2019] [Indexed: 05/29/2023]
Abstract
Variation in xylem conduit diameter traditionally has been explained by climate, whereas other evidence suggests that tree height is the main driver of conduit diameter. The effect of climate versus stem length on vessel diameter was tested in two tree species (Embothrium coccineum, Nothofagus antarctica) that both span an exceptionally wide precipitation gradient (2300-500 mm). To see whether, when taking stem length into account, plants in wetter areas had wider vessels, not only the scaling of vessel diameter at the stem base across individuals of different heights, but also the tip-to-base scaling along individuals of similar heights across sites were examined. Within each species, plants of similar heights had similar mean vessel diameters and similar tip-to-base widening of vessel diameter, regardless of climate, with the slopes and intercepts of the vessel diameter-stem length relationship remaining invariant within species across climates. This study focusing on within-species variation--thus, avoiding noise associated with the great morphological variation across species--showed unequivocally that plant size, not climate, is the main driver of variation in vessel diameter. Therefore, to the extent that climate selects for differing vessel diameters, it will inevitably also affect plant height.
Collapse
Affiliation(s)
- Alex Fajardo
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP) Camino Baguales s/n, Coyhaique, 5951601, Chile
| | - Cecilia Martínez-Pérez
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de Ciudad Universitaria, Ciudad de México, 04510, México
| | - María Angélica Cervantes-Alcayde
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de Ciudad Universitaria, Ciudad de México, 04510, México
| | - Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito s/n de Ciudad Universitaria, Ciudad de México, 04510, México
| |
Collapse
|
14
|
Zong N, Song M, Zhao G, Shi P. Nitrogen economy of alpine plants on the north Tibetan Plateau: Nitrogen conservation by resorption rather than open sources through biological symbiotic fixation. Ecol Evol 2020; 10:2051-2061. [PMID: 32128137 PMCID: PMC7042762 DOI: 10.1002/ece3.6038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 12/21/2019] [Accepted: 12/31/2019] [Indexed: 11/29/2022] Open
Abstract
Nitrogen (N) is one of the most important factors limiting plant productivity, and N fixation by legume species is an important source of N input into ecosystems. Meanwhile, N resorption from senescent plant tissues conserves nutrients taken up in the current season, which may alleviate ecosystem N limitation. N fixation was assessed by the 15N dilution technique in four types of alpine grasslands along the precipitation and soil nutrient gradients. The N resorption efficiency (NRE) was also measured in these alpine grasslands. The aboveground biomass in the alpine meadow was 4-6 times higher than in the alpine meadow steppe, alpine steppe, and alpine desert steppe. However, the proportion of legume species to community biomass in the alpine steppe and the alpine desert steppe was significantly higher than the proportion in the alpine meadow. N fixation by the legume plants in the alpine meadow was 0.236 g N/m2, which was significantly higher than N fixation in other alpine grasslands (0.041 to 0.089 g N/m2). The NRE in the alpine meadows was lower than in the other three alpine grasslands. Both the aboveground biomass and N fixation of the legume plants showed decreasing trends with the decline of precipitation and soil N gradients from east to west, while the NRE of alpine plants showed increasing trends along the gradients, which indicates that alpine plants enhance the NRE to adapt to the increasing droughts and nutrient-poor environments. The opposite trends of N fixation and NRE along the precipitation and soil nutrient gradients indicate that alpine plants adapt to precipitation and soil nutrient limitation by promoting NRE (conservative nutrient use by alpine plants) rather than biological N fixation (open sources by legume plants) on the north Tibetan Plateau.
Collapse
Affiliation(s)
- Ning Zong
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
| | - Minghua Song
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
| | - Guangshuai Zhao
- China National Forestry-Grassland Economics and Development Research CenterNational Forestry and Grassland AdministrationBeijingChina
| | - Peili Shi
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
- College of Resources and EnvironmentUniversity of Chinese Academy of SciencesBeijingChina
| |
Collapse
|
15
|
Araya JP, González M, Cardinale M, Schnell S, Stoll A. Microbiome Dynamics Associated With the Atacama Flowering Desert. Front Microbiol 2020; 10:3160. [PMID: 32038589 PMCID: PMC6990129 DOI: 10.3389/fmicb.2019.03160] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 12/30/2019] [Indexed: 11/13/2022] Open
Abstract
In a desert, plants as holobionts quickly respond to resource pulses like precipitation. However, little is known on how environment and plants modulate the rhizosphere-associated microbiome. As a model species to represent the Atacama Desert bloom, Cistanthe longiscapa (Montiaceae family) was selected to study the influence of abiotic and biotic environment on the diversity and structure of the microbiota associated to its rhizosphere. We analyzed the rhizosphere and soil microbiome along a North-South precipitation gradient and between a dry and rainy year by using Illumina high−throughput sequencing of 16S rRNA gene fragments and ITS2 regions for prokaryotes and fungi, respectively. In the rhizosphere of C. longiscapa the microbiota clearly differs in composition and structure from the surrounding bulk soil. The fungal and bacterial communities respond differently to environmental conditions. The diversity and richness of fungal OTUs were negatively correlated with aridity, as predicted. The community structure was predominantly influenced by other soil characteristics (pH, organic matter content) but not by aridity. In contrast, diversity, composition, and structure of the bacterial community were not influenced by aridity or any other evaluated soil parameter. These findings coincide with the identification of mainly site-specific microbial communities, not shared along the sites. These local communities contain a group of OTUs, which are exclusive to the rhizosphere of each site and presumably vertically inherited as seed endophytes. Their ecological functions and dispersal mechanisms remain unclear. The analysis of co-occurrence patterns highlights the strong effect of the desert habitat over the soil- and rhizosphere-microbiome. The site-independent enrichment of only a small bacterial cluster consistently associated with the rhizosphere of C. longiscapa further supports this conclusion. In a rainy year, the rhizosphere microbiota significantly differed from bulk and bare soil, whereas in a dry year, the community structure of the former rhizosphere approximates to the one found in the bulk. In the context of plant–microbe interactions in desert environments, our study contributes new insights into the importance of aridity in microbial community structure and composition, discovering the influence of other soil parameters in this complex dynamic network, which needs further to be investigated.
Collapse
Affiliation(s)
| | - Máximo González
- Centro de Estudios Avanzados en Zonas Áridas, La Serena, Chile
| | - Massimiliano Cardinale
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy.,Institute of Applied Microbiology, Justus Liebig University Giessen, Giessen, Germany
| | - Sylvia Schnell
- Institute of Applied Microbiology, Justus Liebig University Giessen, Giessen, Germany
| | - Alexandra Stoll
- Centro de Estudios Avanzados en Zonas Áridas, La Serena, Chile.,Instituto de Investigación Multidisciplinario en Ciencia y Tecnología, Universidad de La Serena, La Serena, Chile
| |
Collapse
|
16
|
Zong N, Zhao G, Shi P. Different sensitivity and threshold in response to nitrogen addition in four alpine grasslands along a precipitation transect on the Northern Tibetan Plateau. Ecol Evol 2019; 9:9782-9793. [PMID: 31534693 PMCID: PMC6745826 DOI: 10.1002/ece3.5514] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 07/10/2019] [Accepted: 07/10/2019] [Indexed: 11/29/2022] Open
Abstract
The increase in atmospheric nitrogen (N) deposition has resulted in some terrestrial ecological changes. In order to identify the response of sensitive indicators to N input and estimate the sensitivity and saturation thresholds in alpine grasslands, we set up a series of multilevel N addition experiments in four types of alpine grasslands (alpine meadow [AM], alpine meadow-steppe [AMS], alpine steppe [AS], and alpine desert-steppe [ADS]) along with a decreasing precipitation gradient from east to west on the Northern Tibetan Plateau. N addition only had significant effects on species diversity in AMS, while had no effects on the other three alpine grasslands. Aboveground biomass of grasses and overall community in ADS were enhanced with increasing N addition, but such effects did not occur in AS. Legume biomass in ADS and AS showed similar unimodal patterns and exhibited a decreasing tend in AM. Regression fitting showed that the most sensitive functional groups were grasses, and the N saturation thresholds were 103, 115, 136, and 156 kg N hm-2 year-1 in AM, AMS, AS, and ADS, respectively. This suggests that alpine grasslands become more and more insensitive to N input with precipitation decrease. N saturation thresholds also negatively correlated with soil N availability. N sensitivity differences caused by precipitation and nutrient availability suggest that alpine grasslands along the precipitation gradient will respond differently to atmospheric N deposition in the future global change scenario. This different sensitivity should also be taken into consideration when using N fertilization to restore degraded grasslands.
Collapse
Affiliation(s)
- Ning Zong
- Lhasa National Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
| | - Guangshuai Zhao
- Lhasa National Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
- China National Forestry Economics and Development Research CenterBeijingChina
| | - Peili Shi
- Lhasa National Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| |
Collapse
|
17
|
Frauendorf TC, MacKenzie RA, Tingley RW, Frazier AG, Riney MH, El-Sabaawi RW. Evaluating ecosystem effects of climate change on tropical island streams using high spatial and temporal resolution sampling regimes. Glob Chang Biol 2019; 25:1344-1357. [PMID: 30712279 DOI: 10.1111/gcb.14584] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/30/2018] [Accepted: 01/23/2019] [Indexed: 06/09/2023]
Abstract
Climate change is expected to alter precipitation patterns worldwide, which will affect streamflow in riverine ecosystems. It is vital to understand the impacts of projected flow variations, especially in tropical regions where the effects of climate change are expected to be one of the earliest to emerge. Space-for-time substitutions have been successful at predicting effects of climate change in terrestrial systems by using a spatial gradient to mimic the projected temporal change. However, concerns have been raised that the spatial variability in these models might not reflect the temporal variability. We utilized a well-constrained rainfall gradient on Hawaii Island to determine (a) how predicted decreases in flow and increases in flow variability affect stream food resources and consumers and (b) if using a high temporal (monthly, four streams) or a high spatial (annual, eight streams) resolution sampling scheme would alter the results of a space-for-time substitution. Declines in benthic and suspended resource quantity (10- to 40-fold) and quality (shift from macrophyte to leaf litter dominated) contributed to 35-fold decreases in macroinvertebrate biomass with predicted changes in the magnitude and variability in the flow. Invertebrate composition switched from caddisflies and damselflies to taxa with faster turnover rates (mosquitoes, copepods). Changes in resource and consumer composition patterns were stronger with high temporal resolution sampling. However, trends and ranges of results did not differ between the two sampling regimes, indicating that a suitable, well-constrained spatial gradient is an appropriate tool for examining temporal change. Our study is the first to investigate resource to community wide effects of climate change on tropical streams on a spatial and temporal scale. We determined that predicted flow alterations would decrease stream resource and consumer quantity and quality, which can alter stream function, as well as biomass and habitat for freshwater, marine, and terrestrial consumers dependent on these resources.
Collapse
Affiliation(s)
- Therese C Frauendorf
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Richard A MacKenzie
- Institute of Pacific Islands Forestry, Pacific Southwest Research Station, USDA Forest Service, Hilo, Hawaii
| | - Ralph W Tingley
- Missouri Cooperative Fish and Wildlife Research Unit, The School of Natural Resources, University of Missouri, Columbia, Missouri
| | | | - Michael H Riney
- Shasta Valley Resource Conservation District, Yreka, California
| | - Rana W El-Sabaawi
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| |
Collapse
|
18
|
García-Cervigón AI, Olano JM, von Arx G, Fajardo A. Xylem adjusts to maintain efficiency across a steep precipitation gradient in two coexisting generalist species. Ann Bot 2018; 122:461-472. [PMID: 29800073 PMCID: PMC6110345 DOI: 10.1093/aob/mcy088] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/07/2018] [Indexed: 05/05/2023]
Abstract
BACKGROUND AND AIMS Trees adjust the configuration of their conductive system in response to changes in water availability, maximizing efficiency in wet environments and increasing safety in dry habitats. However, evidence of this general trend is not conclusive. Generalist species growing across broad climatic gradients provide an ideal framework to assess intra-specific xylem adjustments under contrasting environmental conditions. Our aims were to compare the response of xylem traits to variations in precipitation of two co-occurring generalist tree species, and to assess climate control on xylem trait variability and co-ordination. METHODS We evaluated xylem traits of Embothrium coccineum (Proteaceae, evergreen) and Nothofagus antarctica (Nothofagaceae, deciduous) in three areas across an abrupt precipitation gradient, from 500 to 2500 mm, in southern Chile. We measured wood density, vessel lumen area and density, percentage of conductive area and vessel grouping, and estimated the hydraulic function from anatomical measurements in 60 individuals per species. KEY RESULTS Both species shared a common pattern of response along the precipitation gradient, with an increase in vessel density with dryness, but without changes in estimated hydraulic conductivity. Xylem traits in E. coccineum were more variable and more responsive to the climate gradient, decreasing vessel lumen area and increasing wood density, whereas vessel grouping showed contrasting patterns between species. Additionally, the analysis of trait co-ordination at the individual level revealed a tighter co-ordination among xylem traits in E. coccineum. CONCLUSIONS Estimated xylem efficiency was maintained in combination with different levels of expected xylem safety within species. Reduction in vessel lumen area was compensated through large increases in vessel density, thus breaking the trade-off between xylem efficiency and safety. Otherwise, the existence of alternative internal adjustments in coexisting species to face similar climatic constraints might increase resilience of temperate forests against unpredictable changes in climatic conditions.
Collapse
Affiliation(s)
- Ana I García-Cervigón
- Departamento de Biología, Universidad de Cádiz, Campus Universitario de Puerto Real, Puerto Real, Spain
- For correspondence. E-mail
| | - José M Olano
- Departamento de Ciencias Agroforestales, EiFAB, Universidad de Valladolid, Soria, Spain
| | - Georg von Arx
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Alex Fajardo
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP), Coyhaique, Chile
| |
Collapse
|
19
|
Qian J, Wang Z, Klimešová J, Lü X, Kuang W, Liu Z, Han X. Differences in below-ground bud bank density and composition along a climatic gradient in the temperate steppe of northern China. Ann Bot 2017; 120. [PMID: 28633337 PMCID: PMC5691867 DOI: 10.1093/aob/mcx072] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
BACKGROUND AND AIMS Understanding the changes in below-ground bud bank density and composition along a climatic gradient is essential for the exploration of species distribution pattern and vegetation composition in response to climatic changes. Nevertheless, investigations on bud banks along climatic gradients are still scarce. The below-ground bud bank is expected to be reduced in size in arid conditions, and costly, bud-bearing organs with long spacers would be replaced by more compact forms with buds that are better protected than those found in moist conditions. METHODS How total bud density and composition (different bud bank types) change with aridity (calculated value 0·43-0·91), mean annual precipitation (MAP; 93-420 mm) and mean annual temperature (MAT; -1·51 to 6·93 °C) was tested at 21 sites along a 2500-km climatic gradient in the temperate steppe of northern China. CONCLUSIONS Belowground bud bank density decreases towards the dry, hot end of the climatic gradient. Based on the distribution of bud types along the climatic gradient, bulb buds and tiller buds of tussock grasses seem to be more resistant to environmental stress than rhizome buds. The dominance of annual species and smaller bud banks in arid region implies that plant reproductive strategies and vegetation composition will be shifted in scenarios of increased drought under future climate change.
Collapse
Affiliation(s)
- Jianqiang Qian
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, P. R. China
- Department of Functional Ecology, Institute of Botany ASCR, CZ-379 82 Třeboň, Czech Republic
| | - Zhengwen Wang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, P. R. China
| | - Jitka Klimešová
- Department of Functional Ecology, Institute of Botany ASCR, CZ-379 82 Třeboň, Czech Republic
| | - Xiaotao Lü
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, P. R. China
| | - Wennong Kuang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, P. R. China
| | - Zhimin Liu
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, P. R. China
- For correspondence. E-mail
| | - Xingguo Han
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, P. R. China
| |
Collapse
|
20
|
Zhao G, Shi P, Wu J, Xiong D, Zong N, Zhang X. Foliar nutrient resorption patterns of four functional plants along a precipitation gradient on the Tibetan Changtang Plateau. Ecol Evol 2017; 7:7201-7212. [PMID: 28944011 PMCID: PMC5606856 DOI: 10.1002/ece3.3283] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 03/30/2017] [Accepted: 07/03/2017] [Indexed: 12/05/2022] Open
Abstract
Nutrient resorption from senesced leaves as a nutrient conservation strategy is important for plants to adapt to nutrient deficiency, particularly in alpine and arid environment. However, the leaf nutrient resorption patterns of different functional plants across environmental gradient remain unclear. In this study, we conducted a transect survey of 12 communities to address foliar nitrogen (N) and phosphorus (P) resorption strategies of four functional groups along an eastward increasing precipitation gradient in northern Tibetan Changtang Plateau. Soil nutrient availability, leaf nutrient concentration, and N:P ratio in green leaves ([N:P]g) were linearly correlated with precipitation. Nitrogen resorption efficiency decreased, whereas phosphorus resorption efficiency except for sedge increased with increasing precipitation, indicating a greater nutrient conservation in nutrient-poor environment. The surveyed alpine plants except for legume had obviously higher N and P resorption efficiencies than the world mean levels. Legumes had higher N concentrations in green and senesced leaves, but lowest resorption efficiency than nonlegumes. Sedge species had much lower P concentration in senesced leaves but highest P resorption efficiency, suggesting highly competitive P conservation. Leaf nutrient resorption efficiencies of N and P were largely controlled by soil and plant nutrient, and indirectly regulated by precipitation. Nutrient resorption efficiencies were more determined by soil nutrient availability, while resorption proficiencies were more controlled by leaf nutrient and N:P of green leaves. Overall, our results suggest strong internal nutrient cycling through foliar nutrient resorption in the alpine nutrient-poor ecosystems on the Plateau. The patterns of soil nutrient availability and resorption also imply a transit from more N limitation in the west to a more P limitation in the east Changtang. Our findings offer insights into understanding nutrient conservation strategy in the precipitation and its derived soil nutrient availability gradient.
Collapse
Affiliation(s)
- Guangshuai Zhao
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
- China National Forestry Economics and Development Research CenterBeijingChina
| | - Peili Shi
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
- College of Resource and EnvironmentUniversity of Chinese Academy of SciencesBeijingChina
| | - Jianshuang Wu
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
- Functional BiodiversityDahlem Center of Plant ScienceFree University of BerlinBerlinGermany
| | - Dingpeng Xiong
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
| | - Ning Zong
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
| | - Xianzhou Zhang
- Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina
- College of Resource and EnvironmentUniversity of Chinese Academy of SciencesBeijingChina
| |
Collapse
|
21
|
Schuldt B, Knutzen F, Delzon S, Jansen S, Müller-Haubold H, Burlett R, Clough Y, Leuschner C. How adaptable is the hydraulic system of European beech in the face of climate change-related precipitation reduction? New Phytol 2016; 210:443-58. [PMID: 26720626 DOI: 10.1111/nph.13798] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 11/06/2015] [Indexed: 05/04/2023]
Abstract
Climate warming will increase the drought exposure of many forests world-wide. It is not well understood how trees adapt their hydraulic architecture to a long-term decrease in water availability. We examined 23 traits characterizing the hydraulic architecture and growth rate of branches and the dependent foliage of mature European beech (Fagus sylvatica) trees along a precipitation gradient (855-594 mm yr(-1) ) on uniform soil. A main goal was to identify traits that are associated with xylem efficiency, safety and growth. Our data demonstrate for the first time a linear increase in embolism resistance with climatic aridity (by 10%) across populations within a species. Simultaneously, vessel diameter declined by 7% and pit membrane thickness (Tm ) increased by 15%. Although specific conductivity did not change, leaf-specific conductivity declined by 40% with decreasing precipitation. Of eight plant traits commonly associated with embolism resistance, only vessel density in combination with pathway redundancy and Tm were related. We did not confirm the widely assumed trade-off between xylem safety and efficiency but obtained evidence in support of a positive relationship between hydraulic efficiency and growth. We conclude that the branch hydraulic system of beech has a distinct adaptive potential to respond to a precipitation reduction as a result of the environmental control of embolism resistance.
Collapse
Affiliation(s)
- Bernhard Schuldt
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Florian Knutzen
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Sylvain Delzon
- UMR BIOGECO INRA-UB, University of Bordeaux, Avenue des Facultés, 33405, Talence, France
| | - Steven Jansen
- Institute for Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Hilmar Müller-Haubold
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Régis Burlett
- UMR BIOGECO INRA-UB, University of Bordeaux, Avenue des Facultés, 33405, Talence, France
| | - Yann Clough
- Centre for Environmental and Climate Research, Faculty of Science, Lund University, Sölvegatan 37, 223 62, Lund, Sweden
| | - Christoph Leuschner
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany
| |
Collapse
|
22
|
Bansal S, Harrington CA, St Clair JB. Tolerance to multiple climate stressors: a case study of Douglas-fir drought and cold hardiness. Ecol Evol 2016; 6:2074-83. [PMID: 27099710 PMCID: PMC4831441 DOI: 10.1002/ece3.2007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/15/2016] [Accepted: 01/18/2016] [Indexed: 12/25/2022] Open
Abstract
Drought and freeze events are two of the most common forms of climate extremes which result in tree damage or death, and the frequency and intensity of both stressors may increase with climate change. Few studies have examined natural covariation in stress tolerance traits to cope with multiple stressors among wild plant populations. We assessed the capacity of coastal Douglas‐fir (Pseudotsuga menziesii var. menziesii), an ecologically and economically important species in the northwestern USA, to tolerate both drought and cold stress on 35 populations grown in common gardens. We used principal components analysis to combine drought and cold hardiness trait data into generalized stress hardiness traits to model geographic variation in hardiness as a function of climate across the Douglas‐fir range. Drought and cold hardiness converged among populations along winter temperature gradients and diverged along summer precipitation gradients. Populations originating in regions with cold winters had relatively high tolerance to both drought and cold stress, which is likely due to overlapping adaptations for coping with winter desiccation. Populations from regions with dry summers had increased drought hardiness but reduced cold hardiness, suggesting a trade‐off in tolerance mechanisms. Our findings highlight the necessity to look beyond bivariate trait–climate relationships and instead consider multiple traits and climate variables to effectively model and manage for the impacts of climate change on widespread species.
Collapse
Affiliation(s)
- Sheel Bansal
- Pacific Northwest Research Station USDA-Forest Service 3625 93rd Avenue SW Olympia Washington 98512
| | - Constance A Harrington
- Pacific Northwest Research Station USDA-Forest Service 3625 93rd Avenue SW Olympia Washington 98512
| | - John Bradley St Clair
- Pacific Northwest Research Station USDA-Forest Service 3200 SW Jefferson Way Corvallis Oregon 97331
| |
Collapse
|
23
|
Patel S, Schell T, Eifert C, Feldmeyer B, Pfenninger M. Characterizing a hybrid zone between a cryptic species pair of freshwater snails. Mol Ecol 2015; 24:643-55. [PMID: 25533031 DOI: 10.1111/mec.13049] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/11/2014] [Accepted: 12/16/2014] [Indexed: 12/25/2022]
Abstract
Characterizing hybrid zones and their dynamics is a central goal in evolutionary biology, but this is particularly challenging for morphologically cryptic species. The lack of conspicuous divergence between parental types means intermediate hybrid forms often go undetected. We aimed to detect and characterize a suspected hybrid zone between a pair of morphologically cryptic lineages of the freshwater snail, Radix. We sampled Radix from across a contact zone between two mitochondrial lineages (Radix balthica and an undescribed lineage termed 'MOTU3') and detected admixture between two nuclear genotype clusters, which were significantly but not categorically associated with the mitochondrial lineages. Using a model selection approach, we show that the admixture cline is best explained by an interaction between precipitation and temperature gradients over the area, rather than geographic distance. We thus hypothesize that the correlation with climatic gradients suggests environmental selection has played a role in maintaining the hybrid zone. In a 2050 climate change scenario, we furthermore predict an expansion of one of the nuclear clusters and a widening of the hybrid zone as the climate warms and dries.
Collapse
Affiliation(s)
- Simit Patel
- Biodiversity und Climate Research Centre by Senckenberg Naturforschende Gesellschaft and Goethe-Universität, 60325, Frankfurt, Germany
| | | | | | | | | |
Collapse
|
24
|
Lai L, Tian Y, Wang Y, Zhao X, Jiang L, Baskin JM, Baskin CC, Zheng Y. Distribution of three congeneric shrub species along an aridity gradient is related to seed germination and seedling emergence. AoB Plants 2015; 7:plv071. [PMID: 26139184 PMCID: PMC4522037 DOI: 10.1093/aobpla/plv071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 06/18/2015] [Indexed: 05/11/2023]
Abstract
Environmental tolerance of a species has been shown to correlate positively with its geographical range. On the Ordos Plateau, three Caragana species are distributed sequentially along the precipitation gradient. We hypothesized that this geographical distribution pattern is related to environmental tolerances of the three Caragana species during seed germination and seedling emergence stages. To test this hypothesis, we examined seed germination under different temperature, light and water potentials, and monitored seedling emergence for seeds buried at eight sand depths and given different amounts of water. Seeds of C. korshinskii germinated to high percentages at 5 : 15 to 25 : 35 °C in both light and darkness, while those of C. intermedia and C. microphylla did so only at 15 : 25 and 25 : 35 °C, respectively. Nearly 30 % of the C. korshinskii seeds germinated at -1.4 MPa at 20 and 25 °C, while no seeds of the other two species did so. Under the same treatments, seedling emergence percentages of C. korshinskii were higher than those of the other two species. The rank order of tolerance to drought and sand burial of the three species is C. korshinskii > C. intermedia > C. microphylla. The amount of precipitation and sand burial depth appear to be the main selective forces responsible for the geographical distribution of these species.
Collapse
Affiliation(s)
- Liming Lai
- Key Laboratory of Resource Plants, Beijing Botanical Garden, West China Subalpine Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, China
| | - Yuan Tian
- Fukang Station of Desert Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, South Beijing Road, Urumqi, Xinjiang, China
| | - Yongji Wang
- Key Laboratory of Resource Plants, Beijing Botanical Garden, West China Subalpine Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, China
| | - Xuechun Zhao
- Key Laboratory of Resource Plants, Beijing Botanical Garden, West China Subalpine Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, China
| | - Lianhe Jiang
- Key Laboratory of Resource Plants, Beijing Botanical Garden, West China Subalpine Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, China
| | - Jerry M Baskin
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Carol C Baskin
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546, USA
| | - Yuanrun Zheng
- Key Laboratory of Resource Plants, Beijing Botanical Garden, West China Subalpine Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, China
| |
Collapse
|
25
|
Fajardo A, Piper FI. High foliar nutrient concentrations and resorption efficiency in Embothrium coccineum (Proteaceae) in southern Chile. Am J Bot 2015; 102:208-216. [PMID: 25667073 DOI: 10.3732/ajb.1400533] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PREMISE OF THE STUDY Southern South American (SA) Proteaceae species growing in volcanic soils have been proposed as potential ecosystem engineers by tapping phosphorus (P) from soil through their cluster roots and shedding nutrient-rich litter to the soil, making it available for other species. We tested whether Embothrium coccineum (Proteaceae) has effectively lower P nutrient resorption efficiency and higher litter P concentrations than co-occurring, non-Proteaceae species. METHODS In southern Chile, we assessed the P and nitrogen (N) resorption efficiency of senescent leaves and fresh litter of E. coccineum and co-occurring tree species in a soil fertility and moisture gradient (600-3000 mm of annual precipitation) in Patagonia, Chile. We determined P and N concentrations, leaf mass per area (LMA), and ratios of N/P and C/N in mature and senescent leaf cohorts and fresh litter. KEY RESULTS Embothrium coccineum showed significantly higher P and N resorption efficiency than co-occurring species; in fact, E. coccineum fresh litter had the lowest P-content. While E. coccineum showed significantly lower fresh litter P concentrations than the rest of the species, it showed significantly higher N concentrations. Embothrium coccineum also had lower LMA and similar N/P and C/N ratios when compared with co-occurring tree species. CONCLUSIONS We found that E. coccineum efficiently mobilized P and, to a lesser extent, N before leaf shedding. We did not find support for the ecosystem engineering hypothesis via shedding P-rich litter. We suggest that southern South American Proteaceae may be taking up other nutrients besides P, probably N, from the young, volcanic soils of this region.
Collapse
Affiliation(s)
- Alex Fajardo
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP) Conicyt-Regional R10C1003, Universidad Austral de Chile, Camino Baguales s/n, Coyhaique 5951601, Chile
| | - Frida I Piper
- Centro de Investigación en Ecosistemas de la Patagonia (CIEP) Conicyt-Regional R10C1003, Universidad Austral de Chile, Camino Baguales s/n, Coyhaique 5951601, Chile
| |
Collapse
|
26
|
Abstract
PREMISE OF THE STUDY Fungal endophytes are symbionts that inhabit aboveground tissues of most terrestrial plants and can affect plant physiology and growth under stressed conditions. In a future faced with substantial climate change, endophytes have the potential to play an important role in plant stress resistance. Understanding both the distributions of endophytes and their functioning in symbiosis with plants are key aspects of predicting their role in an altered climate. METHODS Here we characterized endophytes in grasses across a steep precipitation gradient to examine the relative importance of environmental and spatial factors in structuring endophyte communities. We also tested how 20 endophytes isolated from drier and wetter regions performed in symbiosis with grass seedlings under high and low soil moisture in the greenhouse. KEY RESULTS Environmental factors related to historical and current precipitation were the most important predictors of endophyte communities in the field. On average, endophytic fungi from western sites also reduced plant water loss in the greenhouse compared to fungi from eastern sites. However, there was substantial variability in how individual endophytic taxa affected plant traits under high and low water availability, with up to two orders of magnitude difference in the plasticity of plant traits conferred by the different fungal taxa. CONCLUSIONS While species sorting appears to largely explain local endophyte community composition, their function in symbiosis is not predictable from local environmental conditions. The development of a predictive framework for endophyte function will require further study of individual fungal taxa and genotypes across environmental gradients.
Collapse
Affiliation(s)
- Hannah Giauque
- Section of Integrative Biology, 1 University Station, C0930, University of Texas at Austin, Austin, Texas 78712, USA
| | | |
Collapse
|