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Wang H, Gao C, Ge Q. Low temperature and short daylength interact to affect the leaf senescence of two temperate tree species. TREE PHYSIOLOGY 2022; 42:2252-2265. [PMID: 35708584 DOI: 10.1093/treephys/tpac068] [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: 01/18/2022] [Accepted: 06/11/2022] [Indexed: 06/15/2023]
Abstract
Temperature and photoperiod are two major environmental cues shaping the leaf senescence of temperate tree species. However, how the control of leaf senescence is split between photoperiod and temperature is unknown for many ecologically important species. Here, we conducted a growth chamber experiment to test the effects of temperature (6, 9, 18 and 21°C) and photoperiod (8 and 16 h daylength) on leaf senescence of two temperate tree species (Quercus mongolica Fisch. and Larix principis-rupprechtii Mayr.) distributed in montane forest of China. The results showed that low temperature (LT) alone could induce leaf senescence of both species under long daylength (LD) conditions, but the leaf senescence of L. principis-rupprechtii was more sensitive to the decrease in temperature than that of Q. mongolica under the LD condition. Short daylength (SD) alone could only induce the leaf senescence of L. principis-rupprechtii, suggesting that the photoperiod sensitivity varies between species. SD could accelerate the LT-induced senescence, but the effect of SD reduced with the decrease in temperature. Based on these findings, we developed a new autumn phenology model by incorporating interspecific differences in the photoperiod sensitivity of leaf senescence. Compared with the three existing process-based autumn phenology models, the new model was more robust in simulating the experimental data. When employing these models to available long-term phenological data, our new model also performed best in reproducing the observed leaf senescence date of two closely related species (Quercus robur L. and Larix decidua Mill.). These results enhance our understanding of how LT and SD control leaf senescence. The prediction of the climate change impacts on forest carbon uptake could be improved by incorporating this new autumn phenological model into the terrestrial biosphere models.
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Affiliation(s)
- Huanjiong Wang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences. 11A, Datun Road, Chaoyang District, Beijing 100101, China
| | - Chengxi Gao
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences. 11A, Datun Road, Chaoyang District, Beijing 100101, China
- University of Chinese Academy of Sciences, 19A, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Quansheng Ge
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences. 11A, Datun Road, Chaoyang District, Beijing 100101, China
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2
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Mapping Seasonal Leaf Nutrients of Mangrove with Sentinel-2 Images and XGBoost Method. REMOTE SENSING 2022. [DOI: 10.3390/rs14153679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Monitoring the seasonal leaf nutrients of mangrove forests helps one to understand the dynamics of carbon (C) sequestration and to diagnose the availability and limitation of nitrogen (N) and phosphorus (P). To date, very little attention has been paid to mapping the seasonal leaf C, N, and P of mangrove forests with remote sensing techniques. Based on Sentinel-2 images taken in spring, summer, and winter, this study aimed to compare three machine learning models (XGBoost, extreme gradient boosting; RF, random forest; LightGBM, light gradient boosting machine) in estimating the three leaf nutrients and further to apply the best-performing model to map the leaf nutrients of 15 seasons from 2017 to 2021. The results showed that there were significant differences in leaf nutrients (p < 0.05) across the three seasons. Among the three machine learning models, XGBoost with sensitive spectral features of Sentinel-2 images was optimal for estimating the leaf C (R2 = 0.655, 0.799, and 0.829 in spring, summer, and winter, respectively), N (R2 = 0.668, 0.743, and 0.704) and P (R2 = 0.539, 0.622, and 0.596) over the three seasons. Moreover, the red-edge (especially B6) and near-infrared bands (B8 and B8a) of Sentinel-2 images were efficient estimators of mangrove leaf nutrients. The information of species, elevation, and canopy structure (leaf area index [LAI] and canopy height) would be incorporated into the present model to improve the model accuracy and transferability in future studies.
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3
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Kotowska MM, Wright IJ, Westoby M. Parenchyma Abundance in Wood of Evergreen Trees Varies Independently of Nutrients. FRONTIERS IN PLANT SCIENCE 2020; 11:86. [PMID: 32180778 PMCID: PMC7045414 DOI: 10.3389/fpls.2020.00086] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 01/21/2020] [Indexed: 05/25/2023]
Abstract
The abundance of living cells in wood-mainly as interconnected axial and ray parenchyma networks-varies widely between species. However, the functional significance of this variation and its role in plant ecological strategies is poorly understood, as is the extent to which different parenchyma fractions are favored in relation to soil nutrients and hydraulic functions. We analyzed wood tissue fractions of 16 Australian angiosperm species sampled from two nearby areas with similar climate but very different soil nutrient profiles and investigated structure-function links with soil and tissue nutrient concentrations and other plant traits. We expected the variation in parenchyma fractions to influence nutrient concentrations in wood xylem, and to find species with lower parenchyma fractions and accordingly lower nutrient requirements on lower-nutrient soils. Surprisingly, both axial and ray parenchyma fractions were mostly unrelated to tissue and soil nutrient concentrations, except for nitrogen concentration in stem sapwood. Species from low nutrient soils showed higher fractional P translocation from both leaves and sapwood, but little patterning with respect to tissue nitrogen. While species from high and low nutrient soils clearly clustered along the soil-fertility axis, their tissue composition varied independently from plant functional traits related to construction costs and hydraulic anatomy. Our findings imply that there is considerable variation among species in the nutrient concentrations within different parenchyma tissues. The anatomical composition of wood tissue seems unrelated to plant nutrient requirements. Even though xylem parenchyma is involved in metabolic functions such as nutrient translocation and storage, parenchyma abundance on its own does not directly explain variation in these functions, even in co-occurring species. While parenchyma is highly abundant in wood of angiosperm trees, we are still lacking a convincing ecological interpretation of its variability and role in whole-tree nutrient budgets.
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Affiliation(s)
- Martyna M. Kotowska
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
- Department of Plant Ecology and Ecosystems Research, University of Göttingen, Göttingen, Germany
| | - Ian J. Wright
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Mark Westoby
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
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4
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Translocation of cesium in the branches of Japanese cedar (Cryptomeria japonica) and Konara oak (Quercus serrata). J Radioanal Nucl Chem 2019. [DOI: 10.1007/s10967-019-06996-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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5
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Yoshihara T, Yoschenko V, Watanabe K, Keitoku K. A through year behavior of 137Cs in a Japanese flowering cherry tree in relation to that of potassium. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 202:32-40. [PMID: 30776701 DOI: 10.1016/j.jenvrad.2019.01.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/09/2019] [Accepted: 01/24/2019] [Indexed: 06/09/2023]
Abstract
To understand the transfer of radiocesium (137Cs) in inside of deciduous trees, changes in 137Cs activity concentrations, primarily derived from the Fukushima accident in March 2011, were observed in the upper parts of a Japanese flowering cherry tree (Prunus x yedoensis cv. Somei-Yoshino) between 2015 and 2018. The sampling of the foliar parts occurred over the entire leaf life span from winter bud to litterfall and those of the branches were distinguished based on emergence years (2017, 2016, 2015, 2014-2011, and 2010/before). First, every tissue demonstrated a clear seasonal variation in 137Cs activity concentration. Second, a synchrony of seasonal variations in 137Cs activity concentration with those in the biological analogue of K concentration was observed in foliar parts during their growth season, but not in branches nor during the other seasons. With respect to the timing of changes in each tissue with tree phenology, it is possible that K and 137Cs alternate between leaves and branches via the same translocation mechanisms. The resorption efficiencies (i.e., 1 - [the concentrations in the last litterfall]/[the maximum concentrations in green leaves]) of K and 137Cs were 76% and 46% in average, respectively. In addition, both leaf buds and branches played an important role as reservoirs during dormancy. The buds storage ratio before and after bud burst (i.e., [the inventories in buds at the end of defoliation]/[those before and after bud burst]) for K were 0.57 and 0.10 in median, respectively, and those for and 137Cs were 1.14 and 0.14 in median, respectively. Consequently, the transfer of 137Cs in inside of trees was still visible seven years after deposition, even though the annual reduction in 137Cs activity concentration was apparent in each tissue.
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Affiliation(s)
- Toshihiro Yoshihara
- Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 1646 Abiko, Chiba, 270-1194, Japan.
| | - Vasyl Yoschenko
- Institute of Environmental Radioactivity of Fukushima University (IER), 1 Kanayagawa, Fukushima, Fukushima, 960-1296, Japan
| | - Kenji Watanabe
- Institute of Environmental Radioactivity of Fukushima University (IER), 1 Kanayagawa, Fukushima, Fukushima, 960-1296, Japan
| | - Koji Keitoku
- Institute of Environmental Radioactivity of Fukushima University (IER), 1 Kanayagawa, Fukushima, Fukushima, 960-1296, Japan; Minamisoma City Hall, Odaka Ward Community Promotion Division, 2-28 Moto-machi Odaka, Minami Soma, Fukushima, 979-2195, Japan
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6
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Sousa-Souto L, Bocchiglieri A, Dias DDM, Ferreira AS, Filho JPDL. Changes in leaf chlorophyll content associated with flowering and its role in the diversity of phytophagous insects in a tree species from a semiarid Caatinga. PeerJ 2018; 6:e5059. [PMID: 30042875 PMCID: PMC6055590 DOI: 10.7717/peerj.5059] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 06/03/2018] [Indexed: 11/20/2022] Open
Abstract
Phytophagous insects choose their feeding resources according to their own requirements, but their feeding preferences in the semiarid Caatinga have rarely been studied. Flowering trees leads to a greater diversity of flower visitors and their predators in the host plant, but little is known about why the diversity of phytophagous insects not associated with flowers is also increased. The purpose of this study was to evaluate the diversity of sap-sucking, wood-boring and leaf-chewing insects associated with leaf chlorophyll content in flowering and non-flowering plants of Poincianella pyramidalis, an endemic tree of Caatinga. We used a leaf chlorophyll index (LCI) as a surrogate for resource quality, and an entomological umbrella to collect phytophagous insects. We show that trees which bloomed demonstrated higher chlorophyll content, greater abundance and a significant difference in the composition of phytophagous insect species when compared to non-flowering trees (p < 0.05). The results suggest that not only the presence of flowers themselves, but also the higher nutritional quality of leaf tissue, can explain the differences in species diversity and abundance of phytophagous insects. Exceptional flowering trees in the Caatinga area studied may thus act as spots of high quality resources, favouring changes in the diversity of insects in this environment.
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Affiliation(s)
- Leandro Sousa-Souto
- Programa de Pós-graduação em Ecologia e Conservação, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil
| | - Adriana Bocchiglieri
- Programa de Pós-graduação em Ecologia e Conservação, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil
| | - Douglas de M Dias
- Programa de Pós-graduação em Ecologia, Conservação e Manejo da Vida Silvestre, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | - José P de L Filho
- Programa de Pós-graduação em Ecologia, Conservação e Manejo da Vida Silvestre, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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7
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Gavrichkova O, Liberati D, de Dato G, Abou Jaoudé R, Brugnoli E, de Angelis P, Guidolotti G, Pausch J, Spohn M, Tian J, Kuzyakov Y. Effects of rain shortage on carbon allocation, pools and fluxes in a Mediterranean shrub ecosystem - a 13C labelling field study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 627:1242-1252. [PMID: 30857089 DOI: 10.1016/j.scitotenv.2018.01.311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/29/2018] [Accepted: 01/29/2018] [Indexed: 06/09/2023]
Abstract
Hydrological cycle is expected to become the primary cause of ecosystem's degradation in near future under changing climate. Rain manipulation experiments under field conditions provide accurate picture on the responses of biotic processes to changed water availability for plants. A field experiment, mimicking expected changes in rain patterns, was established in a Mediterranean shrub community at Porto Conte, Italy, in 2001. In November 2011 Cistus monspeliensis, one of the dominating shrub species in the Mediterranean basin, was 13C labelled on plots subjected to extended rain shortage period and on control non manipulated plots. Carbon (C) allocation was traced by 13C dynamics in shoots, shoot-respired CO2, roots, microbial biomass, K2SO4-extractable C and CO2 respired from soil. Most of the recovered 13C (60%) was respired by shoots within 2weeks in control plots. In rain shortage treatment, 13C remained incorporated in aboveground plant parts. Residence time of 13C in leaves was longer under the rain shortage because less 13C was lost by shoot respiration and because 13C was re-allocated to leaves from woody tissues. The belowground C sink was weak (3-4% of recovered 13C) and independent on rain manipulation. Extended rain shortage promoted C exudation into rhizosphere soil in expense of roots. Together with lowered photosynthesis, this "save" economy of new C metabolites reduces the growing season under rain shortage resulting in decrease of shrub cover and C losses from the system on the long-term.
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Affiliation(s)
- Olga Gavrichkova
- Institute of Agro Environmental and Forest Biology, National Research Council, Porano 05010, Monterotondo Scalo 00015 and Cinte Tesino 38050, Italy; Peoples Friendship University of Russia (RUDN University), 117198 Moscow, Russian Federation.
| | - Dario Liberati
- Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo 01100, Italy
| | - Giovanbattista de Dato
- Council for Agricultural Research and Economics (CREA) - Research Centre for Forestry and Wood, 52100 Arezzo, Italy
| | - Renée Abou Jaoudé
- Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo 01100, Italy
| | - Enrico Brugnoli
- Institute of Agro Environmental and Forest Biology, National Research Council, Porano 05010, Monterotondo Scalo 00015 and Cinte Tesino 38050, Italy
| | - Paolo de Angelis
- Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo 01100, Italy
| | - Gabriele Guidolotti
- Institute of Agro Environmental and Forest Biology, National Research Council, Porano 05010, Monterotondo Scalo 00015 and Cinte Tesino 38050, Italy
| | - Johanna Pausch
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen 37077, Germany; Department of Agricultural Soil Science, University of Göttingen, Göttingen 37077, Germany
| | - Marie Spohn
- Department of Soil Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University Bayreuth, Germany
| | - Jing Tian
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen 37077, Germany; Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), 100101 Beijing, China; Department of Agricultural Soil Science, University of Göttingen, Göttingen 37077, Germany
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen 37077, Germany; Peoples Friendship University of Russia (RUDN University), 117198 Moscow, Russian Federation; Institute of Environmental Sciences, Kazan Federal University, 420049 Kazan, Russian Federation; Department of Agricultural Soil Science, University of Göttingen, Göttingen 37077, Germany
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8
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Puglielli G, Varone L. Inherent variation of functional traits in winter and summer leaves of Mediterranean seasonal dimorphic species: evidence of a 'within leaf cohort' spectrum. AOB PLANTS 2018; 10:ply027. [PMID: 29868168 PMCID: PMC5965093 DOI: 10.1093/aobpla/ply027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 04/19/2018] [Indexed: 05/29/2023]
Abstract
The covariation pattern among leaf functional traits involved in resource acquisition has been successfully provided by the leaf economic spectrum (LES). Nevertheless, some aspects such as how the leaf trait variation sources affect LES predictions are still little investigated. Accordingly, the aim of this paper was to test whether leaf trait variations within different leaf cohorts could alter LES. Improving this knowledge can extend the potential of trait-based approaches in simulating future climate effects on ecosystems. A database on leaf morphological and physiological traits from different leaf cohorts of Cistus spp. was built by collecting data from literature. These species are seasonal dimorphic shrubs with two well-defined leaf cohorts during a year: summer leaves (SL) and winter leaves (WL). Traits included: leaf mass area (LMA), leaf thickness (LT), leaf tissue density (LTD), net photosynthetic rate on area (Aa) and mass (Am) base, nitrogen content on area (Na) and mass (Nm) base. The obtained patterns were analysed by standardized major axis regression and then compared with the global spectrum of evergreens and deciduous species. Climatic variable effect on leaf traits was also tested. Winter leaves and SL showed a great inherent variability for all the considered traits. Nevertheless, some relationships differed in terms of slopes or intercepts between SL and WL and between leaf cohorts and the global spectrum of evergreens and deciduous. Moreover, climatic variables differently affected leaf traits in SL and WL. The results show the existence of a 'within leaf cohort' spectrum, providing the first evidence on the role of leaf cohorts as LES source of variation. In fact, WL showed a high return strategy as they tended to maximize, in a short time, resource acquisition with a lower dry mass investment, while SL were characterized by a low return strategy.
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Affiliation(s)
- Giacomo Puglielli
- Department of Environmental Biology, Sapienza University of Rome, Rome, Italy
| | - Laura Varone
- Department of Environmental Biology, Sapienza University of Rome, Rome, Italy
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9
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Palacio S, Maestro M, Montserrat-Martí G. Differential nitrogen cycling in semiarid sub-shrubs with contrasting leaf habit. PLoS One 2014; 9:e93184. [PMID: 24675650 PMCID: PMC3968058 DOI: 10.1371/journal.pone.0093184] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 02/28/2014] [Indexed: 11/19/2022] Open
Abstract
Nitrogen (N) is, after water, the most limiting resource in semiarid ecosystems. However, knowledge on the N cycling ability of semiarid woody plants is still very rudimentary. This study analyzed the seasonal change in the N concentrations and pools of the leaves and woody organs of two species of semiarid sub-shrubs with contrasting leaf habit. The ability of both species to uptake, remobilize and recycle N, plus the main storage organ for N during summer drought were evaluated. We combined an observational approach in the field with experimental 15N labelling of adult individuals grown in sand culture. Seasonal patterns of N concentrations were different between species and organs and foliar N concentrations of the summer deciduous Lepidium subulatum were almost double those of the evergreen Linum suffruticosum. L. subulatum up took ca. 60% more external N than the evergreen and it also had a higher N resorption efficiency and proficiency. Contrastingly, L. suffruticosum relied more on internal N remobilization for shoot growth. Differently to temperate species, the evergreen stored N preferentially in the main stem and old trunks, while the summer deciduous stored it in the foliage and young stems. The higher ability of L. subulatum to uptake external N can be related to its ability to perform opportunistic growth and exploit the sporadic pulses of N typical of semiarid ecosystems. Such ability may also explain its high foliar N concentrations and its preferential storage of N in leaves and young stems. Finally, L. suffruticosum had a lower ability to recycle N during leaf senescence. These strategies contrast with those of evergreen and deciduous species from temperate and boreal areas, highlighting the need of further studies on semiarid and arid plants.
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Affiliation(s)
- Sara Palacio
- Instituto Pirenaico de Ecología (IPE-CSIC), Avda. Nuestra Señora de la Victoria, Jaca, Huesca, Spain
- * E-mail:
| | - Melchor Maestro
- Instituto Pirenaico de Ecología (IPE-CSIC), Avda. Montañana, Zaragoza, Spain
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10
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Llugany M, Lombini A, Dinelli E, Poschenrieder C, Barceló J. Transfer of selected mineral nutrients and trace elements in the host-hemiparasite association, Cistus-Odontites lutea, growing on and off metal-polluted sites. PLANT BIOLOGY (STUTTGART, GERMANY) 2009; 11:170-178. [PMID: 19228324 DOI: 10.1111/j.1438-8677.2008.00094.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The role of a hemiparasitic life-style in plant resistance to toxic trace elements in polluted soils is unclear. Restriction of metal uptake by the host, restriction of metal transfer from host to parasite, or transformation of metals into a less toxic form may play a role. This study analysed the transfer of selected mineral elements from soil to host (Cistus spp.) and from host to hemiparasite (Odontites lutea) at locations with different metal burdens: a Cu-rich serpentine site, Pb-Ba mine spoil and an unpolluted soil. Highest soil-to-host transfer factors for K, Mg, Ca, Zn, Cu and Pb were observed on the unpolluted soil. Statistically significant differences among locations of host-to-parasite transfer factors were only found for Ca and Pb. Restriction of transfer of unfavourable Ca/Mg ratios, characteristic at the serpentine site, and of high Pb and Zn concentrations at the Pb-Ba mine occurred mainly at the soil-host, and not at the host-parasite, level. Odontites lutea was able to withstand enhanced Zn and Pb concentrations and low Fe/Cu ratios in shoot tissue without developing toxicity symptoms. This could be caused by specific metal resistance mechanisms in this hemiparasite and/or the transformation and transfer of these metals into a less toxic form by the metal-tolerant host.
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Affiliation(s)
- M Llugany
- Laboratory of Fisiología Vegetal, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, Spain
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11
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Palacio S, Milla R, Albuixech J, Pérez-Rontomé C, Camarero JJ, Maestro M, Montserrat-Martí G. Seasonal variability of dry matter content and its relationship with shoot growth and nonstructural carbohydrates. THE NEW PHYTOLOGIST 2008; 180:133-142. [PMID: 18643937 DOI: 10.1111/j.1469-8137.2008.02569.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This study assesses how different phases of shoot growth underlie seasonal change in leaf and stem dry matter content (LDMC and SDMC, respectively) of 12 woody Mediterranean species. The relationship between LDMC and nonstructural carbohydrate (NSC) concentrations is also explored and the seasonal vs interspecies variability of LDMC compared. LDMC, SDMC and shoot elongation rate (SER) were measured on a monthly basis for a minimum of 12 months. Bud growth rate (BGR) and NSC concentrations were also assessed in several of the study species. LDMC and SDMC decreased during shoot elongation in spring and increased in summer, showing a significant negative correlation with SER, but were unrelated to BGR. Half of the species analysed showed a positive relationship between LDMC and NSC. Seasonal fluctuations of LDMC within species were higher than interspecies differences, and species ranking was significantly affected by the month of sampling, except during winter months. Seasonal changes in LDMC and SDMC are mainly related to shoot elongation phenology, and NSC sink-source relationships between old and growing organs can explain this relationship in some species. Owing to the high seasonal variability in LDMC, it is recommended that samples for comparative purposes should be collected as close to the winter as possible.
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Affiliation(s)
- Sara Palacio
- Instituto Pirenaico de Ecología (CSIC). Apdo. 202, 50192 Zaragoza, Spain
- Current address: Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, UK
| | - Rubén Milla
- Area de Biodiversidad y Conservación, Universidad Rey Juan Carlos. C/Tulipán s/n, 28933 Móstoles-Madrid, Spain
| | - Jorge Albuixech
- Instituto Pirenaico de Ecología (CSIC). Apdo. 202, 50192 Zaragoza, Spain
| | - Carmen Pérez-Rontomé
- Estación Experimental de Aula Dei (CSIC), Avda Montañana 1.005-50192 Zaragoza, Spain
| | | | - Melchor Maestro
- Instituto Pirenaico de Ecología (CSIC). Apdo. 202, 50192 Zaragoza, Spain
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12
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Milla R, Castro-Díez P, Maestro-Martínez M, Montserrat-Martí G. Costs of reproduction as related to the timing of phenological phases in the dioecious Shrub Pistacia lentiscus L. PLANT BIOLOGY (STUTTGART, GERMANY) 2006; 8:103-11. [PMID: 16435274 DOI: 10.1055/s-2005-872890] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Females of woody dioecious species usually devote more resources to reproduction than males. This may lead to a decrease in female survival and growth. The costs of reproduction, however, can be lightened through a number of mechanisms, as for example avoiding the temporal coincidence of reproduction and vegetative growth. The aim of this study was to evaluate whether males and females of P. lentiscus differ in the timing of their vegetative growth, and to assess whether the sequencing of vegetative growth and reproduction reduces reproductive costs. We monitored phenology in males and females. We also compared male and female allocation of nutrients and biomass in the branch, and the developmental stability of the growing shoots. We did this both prior to and at the end of the fruiting period. Males and females showed similar vegetative and flowering phenologies. Males invested more biomass in flowering, but the sexes showed equal vegetative biomass and nutrient content prior to the fruiting period. In female branches, no trade-off was found between fruit load and current-year vegetative growth. In P. lentiscus, avoiding the overlap of flowering, vegetative growth and fruiting probably contributes to reduce the immediate costs of reproductive efforts, both in males and females.
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Affiliation(s)
- R Milla
- Instituto Pirenaico de Ecología (C.S.I.C.), P.O. Box 202, 50080 Zaragoza, Spain.
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Milla R, Castro-Díez P, Maestro-Martínez M, Montserrat-Martí G. Relationships between phenology and the remobilization of nitrogen, phosphorus and potassium in branches of eight Mediterranean evergreens. THE NEW PHYTOLOGIST 2005; 168:167-78. [PMID: 16159331 DOI: 10.1111/j.1469-8137.2005.01477.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Few studies have examined the effects of plant growth on nutrient remobilization in phenologically contrasting species. Here we evaluated the consequences of above-ground seasonality of growth and leaf shedding on the remobilization of nutrients from branches in eight evergreen Mediterranean phanaerophytes that differ widely in phenology. Vegetative growth, flower bud formation, flowering, fruiting, leaf shedding, and the variations in nitrogen (N), phosphorus (P) and potassium (K) pools in branches throughout the year were monitored in each species. Nitrogen and P remobilization occurred in summer, after vegetative growth and synchronously with leaf shedding. Despite the time-lag between growth and remobilization, the branches that invested more nutrients in vegetative growth also remobilized more nutrients from their old organs. Potassium remobilization peaked in the climatically harshest periods, and appears to be related to osmotic requirements. We conclude that N and P remobilization occurs mainly associated with leaf senescence, which might be triggered by factors such as the replenishment of nutrient reserves in woody organs, the hormonal relations between new and old leaves, or the constraints that summer drought poses on the amount of leaf area per branch in summer.
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Affiliation(s)
- R Milla
- Instituto Pirenaico de Ecología (CSIC), PO Box 202, E-50080 Zaragoza, Spain.
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