Assessing changes in habitat quality due to land use changes in the spur-thighed tortoise Testudo graeca using hierarchical predictive habitat models

摘要: In this study we propose a model-building approach based on the hierarchical integration of main environmental factors (climate, topography/lithology, and land uses) determining distribution spur-thighed tortoise in south-east Spain. Data presence/absence species were primarily information derived from interviews to shepherds. The modelling exercise consisted three steps. First, constructed model for entire region using climate variables, thus obtaining potential climatical model. Second, introduced variables referring topography lithology that fall within climatic range (potential model). Third, by second as starting point, included use obtain actual model. We analysed changes values probability presence given cell between model, assessing areas where habitat quality has decreased, been maintained or increased. spatial representation these was highly coherent. A discriminant analysis linked dropped with agriculture landscapes, whereas those increased located mainly shrublands. Twenty-five per cent (479 km2) became suboptimal when included, which emphasizes importance both dynamics conservation