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Assessment of the impacts of climate change on Mediterranean terrestrial ecosystems based on data from field experiments and long-term monitored field gradients in Catalonia / Josep Peñuelas in Environmental and Experimental Botany, vol (May 2017)  

Public [article]  inEnvironmental and Experimental Botany > vol (May 2017) Titre : Assessment of the impacts of climate change on Mediterranean terrestrial ecosystems based on data from field experiments and long-term monitored field gradients in Catalonia Type de document : Article/Communication Auteurs : Josep Peñuelas, Auteur ; Jordi Sardans, Auteur ; Iolanda Filella, Auteur ; Marc Estiarte, Auteur ; et al., Auteur Année de publication : 2017 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Catalogne (Espagne) [Termes IGN] changement climatique [Termes IGN] climat méditerranéen [Termes IGN] données de terrain [Termes IGN] écosystème forestier [Termes IGN] érosion hydrique [Termes IGN] forêt méditerranéenne [Termes IGN] nutriment végétal [Termes IGN] sécheresse [Termes IGN] sous-bois [Vedettes matières IGN] Végétation et changement climatique Résumé : (auteur) Climate change is increasing temperatures globally and drought in many regions. If climate change continues at its current rate, the resilience of many ecosystems will likely be exceeded, altering their structure and function. A consistent understanding of the impacts, however, remains elusive due to the difficulty of obtaining data of field studies at different scales from local to regional. We review the impacts of climate change on terrestrial ecosystems of the Mediterranean region based mostly on long-term field experiments of climatic manipulation and monitored field sites in Catalonia (NE Spain). These studies provide diverse experimental and observational field evidences that rising temperatures, new patterns of precipitation and other climatic changes are already affecting ecosystems in this Mediterranean region. Rapid genetic, epigenetic and metabolomics changes in plants have been described. They have resulted in changes in morphology, physiology, growth, reproduction, and mortality. Some species are more vulnerable to these changes than others are, which has altered their competitive ability and thereby changed microbial, plant and animal community composition. Many other impacts have been observed in response to climate change, for example an increase in the emission of biogenic volatile organic compounds or an increased risk of fire and a decrease in the absorption of CO2 in periods of drought. A reduction of the capacity to retain nutrients and C in vegetation is accompanied, in the short term, by an increase in soil C and nutrient contents due to a decrease in the enzymatic capacity and mineralization of soil. The projected increase of torrential rainfalls introduces a scenario of uncertain changes in nutrient cycles, soil fertility and nutrient fluxes at medium and long terms. All these changes in water and nutrient availability suggest, though, net losses in the capacity of Mediterranean forests and shrublands to act as C sinks. Future research should quantify C in above- and belowground biomasses and soils under drought and warming, because this necessary information is lacking. Future studies should also investigate the losses of soil nutrients by leaching and erosion, and the possible feedbacks of land cover changes on water availability and regional climate. Policies of environmental and forestry management should take into account these impacts of the environmental and climatic conditions projected for the coming years and decades. Numéro de notice : A2017-232 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.envexpbot.2017.05.012 Date de publication en ligne : 05/06/2018 En ligne : https://doi.org/10.1016/j.envexpbot.2017.05.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85150 [article]

Satellite data as indicators of tree biomass growth and forest dieback in a Mediterranean holm oak forest / Romà Ogaya in Annals of Forest Science, vol 72 n° 1 (January 2015)  

Public [article]  inAnnals of Forest Science > vol 72 n° 1 (January 2015) . - pp 135 - 144 Titre : Satellite data as indicators of tree biomass growth and forest dieback in a Mediterranean holm oak forest Type de document : Article/Communication Auteurs : Romà Ogaya, Auteur ; Adrià Barbeta, Auteur ; Corina Başnou, Auteur ; Josep Peñuelas, Auteur Année de publication : 2015 Article en page(s) : pp 135 - 144 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] biomasse forestière [Termes IGN] climat méditerranéen [Termes IGN] croissance des arbres [Termes IGN] données météorologiques [Termes IGN] Enhanced vegetation index [Termes IGN] évapotranspiration [Termes IGN] forêt méditerranéenne [Termes IGN] image Aqua-MODIS [Termes IGN] image Terra-MODIS [Termes IGN] indice de végétation [Termes IGN] précipitation [Termes IGN] Quercus ilex Résumé : (auteur) Context : In the framework of climate change, decreased tree growth and enhanced mortality induced by hot and dry conditions are increasing in many forests around the world, and particularly in Mediterranean forests. Aims : Our aim was to estimate tree growth and mortality in a Mediterranean holm oak forest, using remote sensing data from MODIS. Methods : We monitored annual increases of aboveground biomass by measuring tree basal area, and we determined tree mortality by counting dead stems. We analyzed the relationships between forest growth and mortality with mean annual values of some MODIS products and meteorological data. Results : Mortality and increases of aboveground biomass correlated well with precipitation, September standardized precipitation/evapotranspiration indices (SPEI), and some MODIS products such as NDVI and enhanced vegetation index EVI. Other MODIS products such as gross primary production (GPP) and net photosynthesis, however, showed no clear relationship with tree mortality or measured increases of biomass. Conclusion : The MODIS products as proxies of ecosystemic productivity (gross primary productivity, net photosynthesis) were weakly correlated with biomass increase, and did not reflect the mortality following the drought of autumn 2011. Nevertheless, NDVI and EVI were efficient indicators of forest productivity and dieback Numéro de notice : A2015-383 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1007/s13595-014-0408-y Date de publication en ligne : 18/09/2014 En ligne : https://doi.org/10.1007/s13595-014-0408-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76875 [article]