干旱区生态环境知识资源中心

The WATERMED project (2000-2004) is founded by the European Union (INCO-med project) and contributes to the international efforts in analysing efficiency in water use, in particular for the Mediterranean Basin countries. The general objective of the WATERMED project is to develop a comprehensive method for the study of the water use and the resistance to the drought of the natural and irrigated vegetation in the Mediterranean Basin, by means of a combined historical and current space-based remote sensing database, vegetation models and field measurements. The Mediterranean basin was selected as the area of study thanks to its high environmental diversity. This area is clearly affected by the risk of the advance of the desert. Analysing multi-temporal data from the NOAA/NASA Pathfinder AVHRR land (PAL) dataset is taking place as part of the WATERMED project, and at the same time REANALYSIS data are used to provide mean monthly climatological data to compare with. The main objective of this study is to map, and monitor land-cover change in the Mediterranean basin between 1981 and 2001. The study consists in combining both the information in the visible/near-infrared bands in terms of Normalised Difference Vegetation Index (NDVI) and in the thermal-infrared bands in terms of Land Surface Temperature (LST), together with climatic data given by the REANALYSIS. The space-temporal dynamics of these parameters have been sought by analysing seasonal and interannual variability. Finally, we analyse the evolution of LST and NDVI for the months of April and July by the use of the Land Cover Dynamic (VCLD) method and compare with the analysis of Reanalysis data.