A New Wetness Index to Evaluate the Soil Water Availability Influence on Gross Primary Production of European Forests

• Published in: Climate (Basel) Vol. 7; no. 3; p. 42
• Main Authors: Proietti, Chiara, Anav, Alessandro, Vitale, Marcello, Fares, Silvano, Fornasier, Maria Francesca, Screpanti, Augusto, Salvati, Luca, Paoletti, Elena, Sicard, Pierre, De Marco, Alessandra
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 19.03.2019
• Subjects: Air pollution; Arid environments; Arid zones; Aridity; Availability; Carbon cycle; Climate change; Climatic extremes; Crown defoliation; Drought; Evaluation; Extreme weather; Forests; Gross Primary Production; modified Temperature Vegetation Wetness Index; MODIS; Moisture content; Photosynthesis; Plant species; Precipitation; Primary production; Productivity; Remote sensing; Sea level; Semi arid environments; Semiarid environments; Site location; Soil; Soil investigations; Soil Moisture; Soil temperature; Soil water; Temperature; Temperature rise; Temporal variations; Trees; Vegetation; Water; Water availability; Water stress; Weather; Weather conditions; Wetness index; Europe
• ISSN: 2225-1154; 2225-1154
• DOI: 10.3390/cli7030042

Rising temperature, drought and more-frequent extreme climatic events have been predicted for the next decades in many regions around the globe. In this framework, soil water availability plays a pivotal role in affecting vegetation productivity, especially in arid or semi-arid environments. However, direct measurements of soil moisture are scarce, and modeling estimations are still subject to biases. Further investigation on the effect of soil moisture on plant productivity is required. This study aims at analyzing spatio-temporal variations of a modified temperature vegetation wetness index (mTVWI), a proxy of soil moisture, and evaluating its effect on gross primary production (GPP) in forests. The study was carried out in Europe on 19 representative tree species during the 2000–2010 time period. Results outline a north–south gradient of mTVWI with minimum values (low soil water availability) in Southern Europe and maximum values (high soil water availability) in Northeastern Europe. A low soil water availability negatively affected GPP from 20 to 80%, as a function of site location, tree species, and weather conditions. Such a wetness index improves our understanding of water stress impacts, which is crucial for predicting the response of forest carbon cycling to drought and aridity.