{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T21:15:17Z","timestamp":1772226917278,"version":"3.50.1"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":49,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Drought frequency and intensity are increasing across Mediterranean ecosystems, threatening drought-adapted species such as cork oak (Quercus suber). In Portugal, cork oak woodlands have exhibited both canopy decline and widespread greening, yet the drivers of these contrasting trends remain poorly understood. Here, we analyze 38 years of summer Normalized Difference Vegetation Index (NDVI) and Standardized Precipitation Evapotranspiration Index (SPEI) data to assess how climate, topography, tree cover change, and land use influence canopy dynamics across cork oak forest and agroforest systems. Despite a marked decline in summer water availability after 2007, 87% of cork oak areas exhibited NDVI increases. SPEI trends were the strongest predictor of NDVI trajectories, with declining water availability exacerbating NDVI loss in browning areas. NDVI declines were more linked to longer SPEI accumulation periods (4\u201316 months), whereas NDVI increases were primarily associated with 1-month SPEI. This contrast indicates that declines are driven by longer-term moisture legacies and greening driven by short-term physiological responses, reflecting distinct ecological processes. Increases in tree cover accelerated NDVI gains, highlighting a structural contribution to greening. Climatic and site conditions further modulated NDVI trends, with decline exacerbated by low soil permeability and hydrological limitation amplified by topography. Overall, widespread greening suggests short-term physiological resilience, potentially supported by CO\u2082 fertilization, but may obscure vulnerability to sustained water deficits. Identifying shifts from short-term to long-term water limitation, and distinguishing divergent risk pathways for canopy loss versus decline, is essential for anticipating transitions from resilience to irreversible canopy degradation in cork oak ecosystems.<\/jats:p>","DOI":"10.2139\/ssrn.6314764","type":"posted-content","created":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T20:43:31Z","timestamp":1772225011000},"source":"Crossref","is-referenced-by-count":0,"title":["Canopy greenness trends in a drying climate: the role of water availability and land use in Mediterranean cork oak ecosystems"],"prefix":"10.2139","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8165-7781","authenticated-orcid":true,"given":"Danielle  Lacerda","family":"Rudley","sequence":"first","affiliation":[]},{"given":"Maria","family":"Caldeira","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8261-2582","authenticated-orcid":true,"given":"David","family":"Coomes","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9786-5374","authenticated-orcid":true,"given":"Valentine","family":"Aubard","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5201-9836","authenticated-orcid":true,"given":"Jo\u00e3o  M.N.","family":"Silva","sequence":"additional","affiliation":[]}],"member":"78","reference":[{"key":"ref1","doi-asserted-by":"crossref","DOI":"10.1038\/sdata.2017.191","article-title":"Terraclimate, a highresolution global dataset of monthly climate and climatic water balance from 1958-2015","volume":"5","author":"J T Abatzoglou","year":"2018","journal-title":"Scientific Data"},{"key":"ref2","doi-asserted-by":"crossref","first-page":"1775","DOI":"10.1007\/s10021-021-00617-9","article-title":"Canopy Cover Loss of Mediterranean Oak Woodlands: Long-term Effects of Management and Climate","volume":"24","author":"V Ac\ufffdcio","year":"2021","journal-title":"Ecosystems"},{"key":"ref3","volume":"4","author":"E Ali","year":"2022","journal-title":"Climate Change 2022: Impacts, Adaptation and Vulnerability. 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