Modelisation Of The Ndvi Temporal Evolution In Forestry Of Castilla Y Leon, Spain, Using Climatic Data

This paper is a description of the methodology applied and results obtained in a study of the relations among the yearly evolution of the NDVI, derived from NOAA-AVHRR images, and meteorological variables. NOAA images are captured daily by the receivers located at our Remote Sensing Laboratory and processed by means of our own software. Air temperature and rainfall recorded by the Spanish Metorological Institute (INM) have been interpolated into the spatial resolution of the AVHRR images. Solar radiation is calculated using Meteosat images, also received at our Laboratory, and a model developed by us. Three forest classes (deciduous forest, evergreen forest and pines) were chosen for 5-year study (1993-1997). These classes have an important presence in Castilla y Leon and also a well differentiated ecological significance. Models to relate the variables have been developed and an ecophysiological interpretation has been done. Finally, the improvement of the models by means of separating the different climatic zones using the classification CLATERES and also by introducing new variables capable to better measure hydric stress is addressed.