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Liu Z, Michalet R, Wang C, Wang Y, Chen J, Cui H, Song H, Wang J, Yang Z, An L, Xiao S, Chen S. Contrasting effects of two phenotypes of an alpine cushion plant on understory species drive community assembly. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160154. [PMID: 36375548 DOI: 10.1016/j.scitotenv.2022.160154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 10/24/2022] [Accepted: 11/09/2022] [Indexed: 06/16/2023]
Abstract
In alpine systems, cushion plants act as foundation species by ameliorating local environmental conditions. Empirical studies indicate that contrasting phenotypes of alpine cushion species have different effects on understory plant species, either facilitative or competitive. Furthermore, dependent species within each community type might also exhibit different responses to each cushion phenotype, which can be clustered into several "response groups". Additionally, these species-groups specific responses to alpine cushion species phenotypes could alter community assembly. However, very few studies have assessed responses of dependent communities at species-group levels, in particular for both above- and below-ground communities. Here, we selected a loose and a tight phenotype of the alpine cushion species Thylacospermum caespitosum in two sites of northwest China, and use the relative intensity of interactions index to quantify cushion plant effects on subordinate communities of plants and soil fungi and bacteria. We assessed variations in responses of both above- and below-ground organisms to cushion plant effects at species-group level. Species-group level analyses showed that the effects of the phenotype varied among groups of each of the three community types, and different species-groups were composed by unique taxa. Additionally, we found that loose cushions enhanced stochastic processes in community assembly, for plants and soil fungi but not for soil bacteria. These variations of phenotypic effects on different species-group induced contrasting taxonomic composition between groups, and alter community assembly thereby. Our study highlights the occurrence of contrasting effects of two phenotypes of a foundation cushion plant on understory plants, soil fungi and bacteria community composition, but not necessarily on their richness. We also showed that assessing responses of understory species at the species-group level allows a more realistic and mechanistic understanding of biotic interactions both for above- and below-ground communities.
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Affiliation(s)
- Ziyang Liu
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Richard Michalet
- Environnements et Paléoenvironnements Océaniques et Continentaux, University of Bordeaux, Bordeaux, France
| | - Chenyue Wang
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Yajun Wang
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Jingwei Chen
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Hanwen Cui
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Hongxian Song
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Jiajia Wang
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Zi Yang
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Lizhe An
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Sa Xiao
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China
| | - Shuyan Chen
- Key Laboratory of Cell Activities and Stress Adaptations Ministry of Education, School of Life Sciences, Lanzhou University, Tianshui Road 222, Lanzhou, Gansu, People's Republic of China.
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2
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Liancourt P, Doležal J. Overgrowth competition or facilitation from cushion plants: Implication for the role of plant-plant interactions. Ecology 2023; 104:e3989. [PMID: 36756970 DOI: 10.1002/ecy.3989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/22/2022] [Accepted: 12/28/2022] [Indexed: 02/10/2023]
Affiliation(s)
- Pierre Liancourt
- Botany Department, State Museum of Natural History Stuttgart, Stuttgart, Germany.,Plant Ecology Group, University of Tübingen, Tübingen, Germany
| | - Jiri Doležal
- Institute of Botany, Czech Academy of Sciences, Pruhonice, Czech Republic.,Department of Botany, Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
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3
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Morcillo L, Bautista S. Interacting water, nutrients, and shrub age control steppe grass‐on‐shrub competition: Implications for restoration. Ecosphere 2022. [DOI: 10.1002/ecs2.4093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Luna Morcillo
- Mediterranean Center for Environmental Studies (CEAM Foundation), Joint Research Unit University of Alicante‐CEAM University of Alicante Alicante Spain
| | - Susana Bautista
- Department of Ecology and IMEM University of Alicante Alicante Spain
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4
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Cock MC, Hierro JL. Plant interactions balance under biotic and abiotic stressors: the importance of herbivory in semi-arid ecosystems. Oecologia 2020; 194:685-694. [PMID: 33094382 DOI: 10.1007/s00442-020-04789-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 10/10/2020] [Indexed: 11/28/2022]
Abstract
Biotic and abiotic stressors commonly co-occur in plant communities and influence interactions between plants. However, their combined effects on plant interactions have not been widely studied and are still unclear. Here, we assessed the balance of interactions between neighboring plants along a grazing gradient and under two water regimes. We conducted a three-year-field experiment in semi-arid central Argentina with transplants of the dominant palatable grass Piptochaetium napostaense growing in Baccharis ulicina and open microsites across a gradient of grazing pressure. Additionally, we established a water addition treatment along that gradient. We recorded herbivory, size, and fecundity of P. napostaense. During the first two years, P. napostaense was consumed less and was larger below Baccharis than in the open. These differences were greatest under high grazing pressure. Differences in fecundity between microsites were only detected under high and medium grazing pressure in the first two years. In the third year, Baccharis lost their leaves for unclear reasons and provided poor herbivory protection; hence, P. napostaense plants in Baccharis were larger than those in the open only under medium and low grazing pressure, and there were no differences in fecundity between microsites under any grazing condition. Water additions exerted no effect on plant interactions. The balance of interactions changed from positive under heavy grazing to neutral at low and no grazing and water availability did not alter that balance. We conclude that herbivore pressure is an important driver of the balance of plant interactions in semi-arid environments.
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Affiliation(s)
- Marina C Cock
- Laboratorio de Ecología, Biogeografía y Evolución Vegetal (LEByEV), Instituto de Ciencias de la Tierra y Ambientales de La Pampa (INCITAP), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Universidad Nacional de La Pampa (UNLPam), Mendoza 109, 6300, Santa Rosa, La Pampa, Argentina. .,Departamento de Biología, Facultad de Ciencias Exactas y Naturales, UNLPam, Uruguay 151, 6300, Santa Rosa, La Pampa, Argentina.
| | - José L Hierro
- Laboratorio de Ecología, Biogeografía y Evolución Vegetal (LEByEV), Instituto de Ciencias de la Tierra y Ambientales de La Pampa (INCITAP), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Universidad Nacional de La Pampa (UNLPam), Mendoza 109, 6300, Santa Rosa, La Pampa, Argentina.,Departamento de Biología, Facultad de Ciencias Exactas y Naturales, UNLPam, Uruguay 151, 6300, Santa Rosa, La Pampa, Argentina
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5
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Wang C, Michalet R, Liu Z, Jiang X, Wang X, Zhang G, An L, Chen S, Xiao S. Disentangling Large- and Small-Scale Abiotic and Biotic Factors Shaping Soil Microbial Communities in an Alpine Cushion Plant System. Front Microbiol 2020; 11:925. [PMID: 32528430 PMCID: PMC7262953 DOI: 10.3389/fmicb.2020.00925] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/20/2020] [Indexed: 12/20/2022] Open
Abstract
Microorganisms play a crucial role in biogeochemical cycles and ecosystem processes, but the key factors driving microbial community structure are poorly understood, particularly in alpine environments. In this study, we aim to disentangle the relative contribution of abiotic and biotic factors shaping bacterial and fungal community structure at large and small spatial and integration scales in an alpine system dominated by a stress-tolerant cushion species Thylacospermum ceaspitosum. These effects were assessed in two mountain ranges of northwest China and for two contrasting phenotypes of the cushion species inhabiting two different microtopographic positions. The large- and small-scale abiotic effects include the site and microhabitat effects, respectively, while the large- and small-scale biotic effects include the effects of cushion presence and cushion phenotype, respectively. Soil microbial communities were characterized by Illumina Miseq sequencing. Uni- and multivariate statistics were used to test the effects of abiotic and biotic factors at both scales. Results indicated that the site effect representing the soil pH and abiotic hydrothermal conditions mainly affected bacterial community structure, whereas fungal community structure was mainly affected by biotic factors with an equal contribution of cushion presence and cushion phenotype effects. Future studies should analyze the direct factors contributing to shaping microbial community structure in particular of the cushion phenotypes.
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Affiliation(s)
- Chenyue Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
| | - Richard Michalet
- Environnements et Paléoenvironnements Océaniques et Continentaux, University of Bordeaux, Bordeaux, France
| | - Ziyang Liu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
| | - Xingpei Jiang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
| | - Xiangtai Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
| | - Gaosen Zhang
- Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China.,Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou, China
| | - Lizhe An
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
| | - Shuyan Chen
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
| | - Sa Xiao
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou, China
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Pescador DS, de la Cruz M, Chacón‐Labella J, Escudero A. The shape is more important than we ever thought: Plant to plant interactions in a high mountain community. Methods Ecol Evol 2019. [DOI: 10.1111/2041-210x.13248] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- David S. Pescador
- Biodiversity and Conservation Unit, Department of Biology, Geology, Physics and Inorganic Chemistry ESCET, URJC; Móstoles Madrid Spain
| | - Marcelino de la Cruz
- Biodiversity and Conservation Unit, Department of Biology, Geology, Physics and Inorganic Chemistry ESCET, URJC; Móstoles Madrid Spain
| | - Julia Chacón‐Labella
- Departamento de Medio Ambiente Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, INIA Madrid Spain
| | - Adrián Escudero
- Biodiversity and Conservation Unit, Department of Biology, Geology, Physics and Inorganic Chemistry ESCET, URJC; Móstoles Madrid Spain
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7
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Zhao R, Zhang H, An L. Plant size influences abundance of floral visitors and biomass allocation for the cushion plant Thylacospermum caespitosum under an extreme alpine environment. Ecol Evol 2019; 9:5501-5511. [PMID: 31110698 PMCID: PMC6509400 DOI: 10.1002/ece3.5147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 03/18/2019] [Accepted: 03/18/2019] [Indexed: 01/18/2023] Open
Abstract
Variation in size may influence the abundance of visitors and reproductive allocation for cushion plants in the extreme alpine environments. To assess effects of plant size on the abundance of main visitors and reproductive allocation in Thylacospermum caespitosum populations at two altitudes, the abundance of the visitors, visiting frequency, total number of flowers, number of fruits, number of unseeded flowers, and reproductive allocation were investigated during the period of reproductive growth. Concurrently, the effects of plant size on the visitors' contributions to fruit setting rate were assessed by a bagging experiment. Our results showed that flies (Musca domestica and Dasyphora asiatica) were the main pollinating insects of T. caespitosum, and they could obvious facilitate (p < 0.05) the fruit setting rate of this cushion plant. Seed set and floral visitation were significantly influenced (p < 0.001) by plant size. Moreover, the reproductive allocation and fruit setting rate of T. caespitosum was influenced (p < 0.001) by plant size. More biomass was allocated to reproduction in plants of greater diameter. There is an increase in reproductive success (increases of fruit number with increase in plant size) in relation to plant size. In conclusion, the extent of M. domestica and D. asiatica to facilitate the fruit setting rate mainly depended on the size of T. caespitosum. Size-dependent reproductive allocation occurred in T. caespitosum and was the chief factor affecting the contribution of flies to fruit setting rate. These traits reflect reproductive fitness of T. caespitosum related to plant size in extreme alpine environments.
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Affiliation(s)
- Ruiming Zhao
- MOE Key Laboratory of Cell Activities and Stress AdaptationsSchool of Life SciencesLanzhou UniversityLanzhouChina
| | - Hua Zhang
- MOE Key Laboratory of Cell Activities and Stress AdaptationsSchool of Life SciencesLanzhou UniversityLanzhouChina
| | - Lizhe An
- The College of ForestryBeijing Forestry UniversityBeijingChina
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8
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Dolezal J, Dvorsky M, Kopecky M, Altman J, Mudrak O, Capkova K, Rehakova K, Macek M, Liancourt P. Functionally distinct assembly of vascular plants colonizing alpine cushions suggests their vulnerability to climate change. ANNALS OF BOTANY 2019; 123:569-578. [PMID: 30541052 PMCID: PMC6417476 DOI: 10.1093/aob/mcy207] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 10/20/2018] [Indexed: 06/02/2023]
Abstract
BACKGROUND AND AIMS Alpine cushion plants can initially facilitate other species during ecological succession, but later on can be negatively affected by their development, especially when beneficiaries possess traits allowing them to overrun their host. This can be reinforced by accelerated warming favouring competitively strong species over cold-adapted cushion specialists. However, little empirical research has addressed the trait-based mechanisms of these interactions. The ecological strategies of plants colonizing the cushion plant Thylacospermum caespitosum (Caryophyllaceae), a dominant pioneer of subnival zones, were studied in the Western Himalayas. METHODS To assess whether the cushion colonizers are phylogenetically and functionally distinct, 1668 vegetation samples were collected, both in open ground outside the cushions and inside their live and dead canopies, in two mountain ranges, Karakoram and Little Tibet. More than 50 plant traits related to growth, biomass allocation and resource acquisition were measured for target species, and the phylogenetic relationships of these species were studied [or determined]. KEY RESULTS Species-based trait-environment analysis with phylogenetic correction showed that in both mountain ranges Thylacospermum colonizers are phylogenetically diverse but functionally similar and are functionally different from species preferring bare soil outside cushions. Successful colonizers are fast-growing, clonal graminoids and forbs, penetrating the cushion by rhizomes and stolons. They have higher root-to-shoot ratios, leaf nitrogen and phosphorus concentrations, and soil moisture and nutrient demands, sharing the syndrome of competitive species with broad elevation ranges typical of the late stages of primary succession. In contrast, the species from open ground have traits typical of stress-tolerant specialists from high and dry environments. CONCLUSION Species colonizing tight cushions of T. caespitosum are competitively strong graminoids and herbaceous perennials from alpine grasslands. Since climate change in the Himalayas favours these species, highly specialized subnival cushion plants may face intense competition and a greater risk of decline in the future.
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Affiliation(s)
- Jiri Dolezal
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
- Department of Botany, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Miroslav Dvorsky
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Martin Kopecky
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Jan Altman
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Ondrej Mudrak
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Katerina Capkova
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Klara Rehakova
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Martin Macek
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Pierre Liancourt
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
- Department of Evolution and Ecology, University of Tübingen, Tübingen, Germany
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9
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Chardon NI, Wipf S, Rixen C, Beilstein A, Doak DF. Local trampling disturbance effects on alpine plant populations and communities: Negative implications for climate change vulnerability. Ecol Evol 2018; 8:7921-7935. [PMID: 30250673 PMCID: PMC6144962 DOI: 10.1002/ece3.4276] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 04/11/2018] [Accepted: 05/17/2018] [Indexed: 11/21/2022] Open
Abstract
Global change is modifying species communities from local to landscape scales, with alterations in the abiotic and biotic determinants of geographic range limits causing species range shifts along both latitudinal and elevational gradients. An important but often overlooked component of global change is the effect of anthropogenic disturbance, and how it interacts with the effects of climate to affect both species and communities, as well as interspecies interactions, such as facilitation and competition. We examined the effects of frequent human trampling disturbances on alpine plant communities in Switzerland, focusing on the elevational range of the widely distributed cushion plant Silene acaulis and the interactions of this facilitator species with other plants. Examining size distributions and densities, we found that disturbance appears to favor individual Silene growth at middle elevations. However, it has negative effects at the population level, as evidenced by a reduction in population density and reproductive indices. Disturbance synergistically interacts with the effects of elevation to reduce species richness at low and high elevations, an effect not mitigated by Silene. In fact, we find predominantly competitive interactions, both by Silene on its hosted and neighboring species and by neighboring (but not hosted) species on Silene. Our results indicate that disturbance can be beneficial for Silene individual performance, potentially through changes in its neighboring species community. However, possible reduced recruitment in disturbed areas could eventually lead to population declines. While other studies have shown that light to moderate disturbances can maintain high species diversity, our results emphasize that heavier disturbance reduces species richness, diversity, as well as percent cover, and adversely affects cushion plants and that these effects are not substantially reduced by plant-plant interactions. Heavily disturbed alpine systems could therefore be at greater risk for upward encroachment of lower elevation species in a warming world.
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Affiliation(s)
- Nathalie Isabelle Chardon
- Environmental Studies ProgramUniversity of ColoradoBoulderUSA
- Mountain EcosystemsWSL Institute for Snow and Avalanche Research SLFDavosSwitzerland
| | - Sonja Wipf
- Mountain EcosystemsWSL Institute for Snow and Avalanche Research SLFDavosSwitzerland
| | - Christian Rixen
- Mountain EcosystemsWSL Institute for Snow and Avalanche Research SLFDavosSwitzerland
| | - Annabarbara Beilstein
- Mountain EcosystemsWSL Institute for Snow and Avalanche Research SLFDavosSwitzerland
- Department of Environmental Systems ScienceETH ZurichZurichSwitzerland
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10
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Zhang G, Zhao W, Zhou H, Yang Q, Wang X. Extreme drought stress shifts net facilitation to neutral interactions between shrubs and sub-canopy plants in an arid desert. OIKOS 2017. [DOI: 10.1111/oik.04630] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gefei Zhang
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Key Laboratory of Eco-hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science; CN-73000 Lanzhou PR China
| | - Wenzhi Zhao
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Key Laboratory of Eco-hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science; CN-73000 Lanzhou PR China
| | - Hai Zhou
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Key Laboratory of Eco-hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science; CN-73000 Lanzhou PR China
| | - Qiyue Yang
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Key Laboratory of Eco-hydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science; CN-73000 Lanzhou PR China
| | - Xiaofen Wang
- Prata cultural College, Gansu Agricultural Univ.; Lanzhou PR China
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11
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Jiang X, Michalet R, Chen S, Zhao L, Wang X, Wang C, An L, Xiao S. Phenotypic effects of the nurseThylacospermum caespitosumon dependent plant species along regional climate stress gradients. OIKOS 2017. [DOI: 10.1111/oik.04512] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xingpei Jiang
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou Univ., 222 Tianshuinan Road; CN-730000 Lanzhou PR China
| | - Richard Michalet
- Univ. of Bordeaux, U.M.R. CNRS, Allée Geoffroy Saint-Hilaire; Pessac France
| | - Shuyan Chen
- Ministry of Education Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Chongqing Univ.; Chongqing PR China
| | - Liang Zhao
- Ministry of Education Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Chongqing Univ.; Chongqing PR China
| | - Xiangtai Wang
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou Univ., 222 Tianshuinan Road; CN-730000 Lanzhou PR China
| | - Chenyue Wang
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou Univ., 222 Tianshuinan Road; CN-730000 Lanzhou PR China
| | - Lizhe An
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou Univ., 222 Tianshuinan Road; CN-730000 Lanzhou PR China
| | - Sa Xiao
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou Univ., 222 Tianshuinan Road; CN-730000 Lanzhou PR China
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12
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Liancourt P, Le Bagousse-Pinguet Y, Rixen C, Dolezal J. SGH: stress or strain gradient hypothesis? Insights from an elevation gradient on the roof of the world. ANNALS OF BOTANY 2017; 120:29-38. [PMID: 28444363 PMCID: PMC5737727 DOI: 10.1093/aob/mcx037] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 03/15/2017] [Indexed: 06/01/2023]
Abstract
BACKGROUND AND AIMS The stress gradient hypothesis (SGH), the view that competition prevails in undisturbed and productive environments, and shifts to facilitation in disturbed or stressful environments, has become a central paradigm in ecology. However, an alternative view proposes that the relationship between biotic interactions and environmental severity should be unimodal instead of monotonic. Possible causes of discrepancies between these two views were examined in the high elevation desert of the arid Trans-Himalayas. METHODS A putative nurse species and its associated plant community was surveyed over its entire elevation range, spanning from alpine to desert vegetation belts. The results were analysed at the community level (vegetation cover and species richness), considering the distinction between the intensity and the importance of biotic interactions. Interactions at the species level (pairwise interactions) were also considered, i.e. the variation of biotic interactions within the niche of a species, for which the abundance (species cover) and probability of occurrence (presence/absence) for the most widespread species along the gradient were distinguished. KEY RESULTS Overall, facilitation was infrequent in our study system; however, it was observed for the two most widespread species. At the community level, the intensity and importance of biotic interactions showed a unimodal pattern. The departure from the prediction of the SGH happened abruptly where the nurse species entered the desert vegetation belt at the lowest elevation. This abrupt shift was attributed to the turnover of species with contrasting tolerances. At the species level, however, facilitation increased consistently as the level of stress increases and individuals deviate from their optimum (increasing strain). CONCLUSION While the stress gradient hypothesis was not supported along our elevation gradient at the community level, the strain gradient hypothesis, considering how species perceive the ambient level of stress and deviate from their optimum, provided a parsimonious explanation for the outcome of plant-plant interactions at both scales.
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Affiliation(s)
- Pierre Liancourt
- Institute of Botany, Czech Academy of Sciences, Dukelská 135, 379 82 Trebon, Czech Republic
| | - Yoann Le Bagousse-Pinguet
- Departamento de Biología y Geología, Física y Química Inorgánica, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, C/ Tulipán s/n, 28933 Móstoles, Spain
| | - Christian Rixen
- WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland
| | - Jiri Dolezal
- Institute of Botany, Czech Academy of Sciences, Dukelská 135, 379 82 Trebon, Czech Republic
- Department of Botany, Faculty of Science, University of South Bohemia, Na Zlate stoce 1, 370 05 Ceske Budejovice, Czech Republic
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13
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Cavieres LA, Hernández‐Fuentes C, Sierra‐Almeida A, Kikvidze Z. Facilitation among plants as an insurance policy for diversity in Alpine communities. Funct Ecol 2015. [DOI: 10.1111/1365-2435.12545] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lohengrin A. Cavieres
- ECOBIOSIS Departamento de Botánica Facultad de Ciencias Naturales y Oceanográficas Universidad de Concepción 4070043 Concepción Chile
- Instituto de Ecología y Biodiversidad Casilla 653 Santiago Chile
| | - Carolina Hernández‐Fuentes
- ECOBIOSIS Departamento de Botánica Facultad de Ciencias Naturales y Oceanográficas Universidad de Concepción 4070043 Concepción Chile
- Instituto de Ecología y Biodiversidad Casilla 653 Santiago Chile
| | - Angela Sierra‐Almeida
- ECOBIOSIS Departamento de Botánica Facultad de Ciencias Naturales y Oceanográficas Universidad de Concepción 4070043 Concepción Chile
- Instituto de Ecología y Biodiversidad Casilla 653 Santiago Chile
| | - Zaal Kikvidze
- 4D Research Institute Ilia State University Room 310 Building E 5 Cholokashvili Ave. Tbilisi 0162 Georgia
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Castanho CT, Oliveira AA, Prado PIKL. Does extreme environmental severity promote plant facilitation? An experimental field test in a subtropical coastal dune. Oecologia 2015; 178:855-66. [DOI: 10.1007/s00442-015-3285-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 02/24/2015] [Indexed: 11/24/2022]
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Pescador DS, Chacón-Labella J, de la Cruz M, Escudero A. Maintaining distances with the engineer: patterns of coexistence in plant communities beyond the patch-bare dichotomy. THE NEW PHYTOLOGIST 2014; 204:140-148. [PMID: 24954264 DOI: 10.1111/nph.12899] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 05/17/2014] [Indexed: 06/03/2023]
Abstract
Two-phase plant communities with an engineer conforming conspicuous patches and affecting the performance and patterns of coexisting species are the norm under stressful conditions. To unveil the mechanisms governing coexistence in these communities at multiple spatial scales, we have developed a new point-raster approach of spatial pattern analysis, which was applied to a Mediterranean high mountain grassland to show how Festuca curvifolia patches affect the local distribution of coexisting species. We recorded 22 111 individuals of 17 plant perennial species. Most coexisting species were negatively associated with F. curvifolia clumps. Nevertheless, bivariate nearest-neighbor analyses revealed that the majority of coexisting species were confined at relatively short distances from F. curvifolia borders (between 0-2 cm and up to 8 cm in some cases). Our study suggests the existence of a fine-scale effect of F. curvifolia for most species promoting coexistence through a mechanism we call 'facilitation in the halo'. Most coexisting species are displaced to an interphase area between patches, where two opposite forces reach equilibrium: attenuated severe conditions by proximity to the F. curvifolia canopy (nutrient-rich islands) and competitive exclusion mitigated by avoiding direct contact with F. curvifolia.
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Affiliation(s)
- David S Pescador
- Departamento de Biología y Geología, Escuela Superior de Ciencias Experimentales y Tecnológicas, Universidad Rey Juan Carlos, c/Tulipán s/n, E-28933, Móstoles, Spain
| | - Julia Chacón-Labella
- Departamento de Biología y Geología, Escuela Superior de Ciencias Experimentales y Tecnológicas, Universidad Rey Juan Carlos, c/Tulipán s/n, E-28933, Móstoles, Spain
| | - Marcelino de la Cruz
- Departamento de Biología y Geología, Escuela Superior de Ciencias Experimentales y Tecnológicas, Universidad Rey Juan Carlos, c/Tulipán s/n, E-28933, Móstoles, Spain
| | - Adrian Escudero
- Departamento de Biología y Geología, Escuela Superior de Ciencias Experimentales y Tecnológicas, Universidad Rey Juan Carlos, c/Tulipán s/n, E-28933, Móstoles, Spain
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Gairola S, Sharma J, Bedi YS. A cross-cultural analysis of Jammu, Kashmir and Ladakh (India) medicinal plant use. JOURNAL OF ETHNOPHARMACOLOGY 2014; 155:925-86. [PMID: 24952280 DOI: 10.1016/j.jep.2014.06.029] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 06/09/2014] [Accepted: 06/12/2014] [Indexed: 05/18/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Jammu & Kashmir (J&K) is a predominantly Himalayan state in the north-western part of India. It has three geographically distinct divisions viz., Jammu, Kashmir and Ladakh, which are immensely rich in their biological and cultural diversity. Medicinal plants are an important element of indigenous medical system of the region. The main goal of the present article is to examine the use of ethnomedicinal plants in three divisions of J&K and to discuss cross-cultural consensus on the use of medicinal plants in these divisions. The article also discusses the gaps in the current state of knowledge on ethnomedicinal plants of the region and gives recommendations for the future studies. MATERIALS AND METHODS Scientific literature on ethnomedicinal field studies conducted in J&K state of India available in the journals, edited books and other scientific databases viz., CAB international, DOAJ, Google Scholar, PubMed, Science direct, SciFinder, Scopus and Web of Science were searched. Only field based ethnomedicinal surveys from last four decades up to December 2013 reporting first hand information on the medicinal plants used to treat human health related ailments by indigenous communities of J&K were included in this study. Venn diagram was used to analyze the cross-cultural consensus on the use of ethnomedicinal plants in the three divisions of J&K. RESULTS A total of 948 plant taxa (923 angiosperms, 12 gymnosperms and 13 pteridophytes) belonging to 129 families, 509 genera, 937 species and 11 varieties have so far been reported to have a traditional medicinal use by indigenous communities of J&K. Asteraceae (60 genera, 132 spp.) was the most frequently used family followed by Fabaceae (32 genera, 50 spp.) and Lamiaceae (27 genera, 55 spp.). 514, 415 and 397 medicinal plants were used in Jammu, Kashmir and Ladakh divisions, respectively. Sixty eight plant taxa were used in all the three divisions, whereas 95 plants were common between Ladakh and Jammu, 127 plants between Ladakh and Kashmir, and 216 plants between Jammu and Kashmir. Maximum numbers of plant taxa were used for treating dermatological problems (321), followed by cold, cough and throat related ailments (250), fever (224), joint and muscle related ailments (215), gastrointestinal disorders (210), urogenital ailments (199), respiratory ailments (151), body pain (135) and gynecological disorders (127). CONCLUSIONS This is the first study from the J&K state, which has examined the medicinal plant use in three divisions of J&K and discussed the promising medicinal plant species with cross-cultural consensus. The analysis of the data suggested that while large numbers of plants are used medicinally in each division, there is a low interregional consensus and high variation between medicinal plants used in these divisions, which is due to both cultural divergence as well as biological distinctness. The issues related to current status of knowledge on medicinal plants used by indigenous communities of J&K have been discussed and some recommendations have been made for future studies on medicinal plants in J&K region.
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Affiliation(s)
- Sumeet Gairola
- Plant Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India; Academy of Scientific and Innovative Research, Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India.
| | - Jyotsana Sharma
- Department of Botany, University of Jammu, Jammu 180006, Jammu & Kashmir, India
| | - Yashbir Singh Bedi
- Plant Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India; Academy of Scientific and Innovative Research, Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India
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Liczner AR, Lortie CJ. A global meta-analytic contrast of cushion-plant effects on plants and on arthropods. PeerJ 2014; 2:e265. [PMID: 24688848 PMCID: PMC3940482 DOI: 10.7717/peerj.265] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 01/19/2014] [Indexed: 11/20/2022] Open
Abstract
Nurse plant facilitation is a commonly reported plant-plant interaction and is an important factor influencing community structure in stressful environments. Cushion plants are an example of alpine nurse plants that modify microclimatic conditions within their canopies to create favourable environments for other plants. In this meta-analysis, the facilitative effects of cushion plants was expanded from previous syntheses of the topic and the relative strength of facilitation for other plants and for arthropods were compared globally.The abundance, diversity, and species presence/absence effect size estimates were tested as plant responses to nurse plants and a composite measure was tested for arthropods. The strength of facilitation was on average three times greater for arthropods relative to all plant responses to cushions. Plant species presence, i.e., frequency of occurrence, was not enhanced by nurse-plants. Cushion plants nonetheless acted as nurse plants for both plants and arthropods in most alpine contexts globally, and although responses by other plant species currently dominate the facilitation literature, preliminary synthesis of the evidence suggests that the potential impacts of nurses may be even greater for other trophic levels.
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Cavieres LA, Brooker RW, Butterfield BJ, Cook BJ, Kikvidze Z, Lortie CJ, Michalet R, Pugnaire FI, Schöb C, Xiao S, Anthelme F, Björk RG, Dickinson KJM, Cranston BH, Gavilán R, Gutiérrez-Girón A, Kanka R, Maalouf JP, Mark AF, Noroozi J, Parajuli R, Phoenix GK, Reid AM, Ridenour WM, Rixen C, Wipf S, Zhao L, Escudero A, Zaitchik BF, Lingua E, Aschehoug ET, Callaway RM. Facilitative plant interactions and climate simultaneously drive alpine plant diversity. Ecol Lett 2013; 17:193-202. [DOI: 10.1111/ele.12217] [Citation(s) in RCA: 231] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 07/08/2013] [Accepted: 10/14/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Lohengrin A. Cavieres
- Departamento de Botánica; Facultad de Ciencias Naturales y Oceanográficas; Universidad de Concepción; Casilla 160-C Concepción Chile
- Instituto de Ecología y Biodiversidad; Casilla 653 Santiago Chile
| | - Rob W. Brooker
- The James Hutton Institute; Craigiebuckler Aberdeen AB15 8QH UK
| | - Bradley J. Butterfield
- Merriam-Powell Center for Environmental Research; Northern Arizona University; P.O. Box 6077 Flagstaff AZ 86011 USA
- Department of Biological Sciences; Northern Arizona University; P.O. Box 5640 Flagstaff AZ 86011 USA
| | - Bradley J. Cook
- Department of Biological Sciences; Minnesota State University; Mankato MN 56001 USA
| | - Zaal Kikvidze
- Institute of Ecology; Ilia State University; 32 I.Chavchavadze Av. Tbilisi 0179 Georgia
| | | | - Richard Michalet
- University of Bordeaux; UMR CNRS 5805 EPOC; 33405 Talence France
| | - Francisco I. Pugnaire
- Estación Experimental de Zonas Áridas; Consejo Superior de Investigaciones Científicas; Carretera de Sacramento s/n; La Cañada de San Urbano; Almería E-04120 Spain
| | - Christian Schöb
- The James Hutton Institute; Craigiebuckler Aberdeen AB15 8QH UK
| | - Sa Xiao
- MOE Key Laboratory of Cell Activities and Stress Adaptations; School of Life Science; Lanzhou University; Lanzhou 730000 People's Republic of China
| | - Fabien Anthelme
- Institut de Recherche pour le Développement (IRD); UMR DIADE/AMAP, CIRAD; TA A51/PS2 Montpellier Cedex 5 34398 France
- Pontificia Universidad Católica del Ecuador; Av. 12 de Octubre y Roca Quito Ecuador
| | - Robert G. Björk
- Department of Earth Sciences; University of Gothenburg; P.O. Box 460 Gothenburg SE-405 30 Sweden
| | | | | | - Rosario Gavilán
- Departamento de Biología Vegetal II; Facultad de Farmacia; Universidad Complutense; Madrid E-28040 Spain
| | - Alba Gutiérrez-Girón
- Departamento de Biología Vegetal II; Facultad de Farmacia; Universidad Complutense; Madrid E-28040 Spain
| | - Robert Kanka
- Institute of Landscape Ecology; Slovak Academy of Sciences; Štefánikova 3 Bratislava 814 99 Slovakia
| | | | - Alan F. Mark
- Department of Botany; University of Otago; P. O. Box 56 Dunedin New Zealand
| | - Jalil Noroozi
- Department of Conservation Biology, Vegetation and Landscape Ecology; University of Vienna; Rennweg 14 Vienna 1030 Austria
| | | | - Gareth K. Phoenix
- Department of Animal and Plant Sciences; The University of Sheffield; Western Bank Sheffield S10 2TN UK
| | - Anya M. Reid
- Department of Biology; York University; 4700 Keele Street Toronto ON M3J 1P3 Canada
| | - Wendy M. Ridenour
- Biology Department; University of Montana Western; Dillon MT 59725 USA
| | - Christian Rixen
- WSL Institute for Snow and Avalanche Research SLF; Fluelastrasse 11 Davos 7260 Switzerland
| | - Sonja Wipf
- WSL Institute for Snow and Avalanche Research SLF; Fluelastrasse 11 Davos 7260 Switzerland
| | - Liang Zhao
- Key Laboratory of Ecohydrology of Inland River Basin; Cold and Arid Regions Environmental and Engineering Research Institute; Chinese Academy of Sciences; 320 Donggang West Road Lanzhou 730000 China
| | - Adrián Escudero
- Departamento de Biología y Geología; Universidad Rey Juan Carlos; Móstoles 28933 Spain
| | - Benjamin F. Zaitchik
- Department of Earth and Planetary Sciences; Johns Hopkins University; 327 Olin Hall, 3400 N. Charles Street Baltimore MD 21218 USA
| | - Emanuele Lingua
- Department TeSAF; University of Padova; Viale dell'Universitá 16 Legnaro 35020 Italy
| | - Erik T. Aschehoug
- Department of Biology; North Carolina State University; P.O. Box 7617 Raleigh NC 27695 USA
| | - Ragan M. Callaway
- Division of Biological Sciences and the Institute on Ecosystems; University of Montana; Missoula MT 59812 USA
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Testing the stress-gradient hypothesis at the roof of the world: effects of the cushion plant Thylacospermum caespitosum on species assemblages. PLoS One 2013; 8:e53514. [PMID: 23326446 PMCID: PMC3542354 DOI: 10.1371/journal.pone.0053514] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 11/30/2012] [Indexed: 11/20/2022] Open
Abstract
Many cushion plants ameliorate the harsh environment they inhabit in alpine ecosystems and act as nurse plants, with significantly more species growing within their canopy than outside. These facilitative interactions seem to increase with the abiotic stress, thus supporting the stress-gradient hypothesis. We tested this prediction by exploring the association pattern of vascular plants with the dominant cushion plant Thylacospermum caespitosum (Caryophyllaceae) in the arid Trans-Himalaya, where vascular plants occur at one of the highest worldwide elevational limits. We compared plant composition between 1112 pair-plots placed both inside cushions and in surrounding open areas, in communities from cold steppes to subnival zones along two elevational gradients (East Karakoram: 4850–5250 m and Little Tibet: 5350–5850 m). We used PERMANOVA to assess differences in species composition, Friedman-based permutation tests to determine individual species habitat preferences, species-area curves to assess whether interactions are size-dependent and competitive intensity and importance indices to evaluate plant-plant interactions. No indications for net facilitation were found along the elevation gradients. The open areas were not only richer in species, but not a single species preferred to grow exclusively inside cushions, while 39–60% of 56 species detected had a significant preference for the habitat outside cushions. Across the entire elevation range of T. caespitosum, the number and abundance of species were greater outside cushions, suggesting that competitive rather than facilitative interactions prevail. This was supported by lower soil nutrient contents inside cushions, indicating a resource preemption, and little thermal amelioration at the extreme end of the elevational gradient. We attribute the negative associations to competition for limited resources, a strong environmental filter in arid high-mountain environment selecting the stress-tolerant species that do not rely on help from other plants during their life cycle and to the fact the cushions do not provide a better microhabitat to grow in.
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Maalouf JP, Le Bagousse-Pinguet Y, Marchand L, Touzard B, Michalet R. The interplay of stress and mowing disturbance for the intensity and importance of plant interactions in dry calcareous grasslands. ANNALS OF BOTANY 2012; 110:821-8. [PMID: 22782241 PMCID: PMC3423810 DOI: 10.1093/aob/mcs152] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
BACKGROUND AND AIMS There is still debate regarding the direction and strength of plant interactions under intermediate to high levels of stress. Furthermore, little is known on how disturbance may interact with physical stress in unproductive environments, although recent theory and models have shown that this interplay may induce a collapse of plant interactions and diversity. The few studies assessing such questions have considered the intensity of biotic interactions but not their importance, although this latter concept has been shown to be very useful for understanding the role of interactions in plant communities. The objective of this study was to assess the interplay between stress and disturbance for plant interactions in dry calcareous grasslands. METHODS A field experiment was set up in the Dordogne, southern France, where the importance and intensity of biotic interactions undergone by four species were measured along a water stress gradient, and with and without mowing disturbance. KEY RESULTS The importance and intensity of interactions varied in a very similar way along treatments. Under undisturbed conditions, plant interactions switched from competition to neutral with increasing water stress for three of the four species, whereas the fourth species was not subject to any significant biotic interaction along the gradient. Responses to disturbance were more species-specific; for two species, competition disappeared with mowing in the wettest conditions, whereas for the two other species, competition switched to facilitation with mowing. Finally, there were no significant interactions for any species in the disturbed and driest conditions. CONCLUSIONS At very high levels of stress, plant performances become too weak to allow either competition or facilitation and disturbance may accelerate the collapse of interactions in dry conditions. The results suggest that the importance and direction of interactions are more likely to be positively related in stressful environments.
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Affiliation(s)
- Jean-Paul Maalouf
- UMR BIOGECO INRA, Ecologie des Communautés, Université Bordeaux, Bât. B2 RDC Est, Talence, France.
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