关键词: 光合有效辐射吸收比率, 年累计生产力, 年最低生产力, 季节变化

Abstract: Increased human activities are seriously disturbing the stability and balance of global ecosystems and threatening biodiversity. As global biodiversity decreases, more and more studies have used remote sensing data to assess biodiversity, environmental threats to habitats, and other issues. Dynamic habitat index (DHI), an indicator of vegetation productivity, can reflect changes in biodiversity. DHI integrates remote sensing data for one year of vegetation productivity, captures seasonal changes in energy use by species in the form of food, and characterizes spatial variation of species richness in terms of vegetation productivity. DHI consists of three indicators: cumulative annual productivity, annual minimum productivity, and seasonal variation in productivity. Cumulative annual productivity is assessed in response to the available energy hypothesis, which integrates the landscape productivity for a year and reflects the overall greenness of the landscape in terms of potential vegetation productivity. Annual minimum productivity is assessed following the environmental stress hypothesis, which mainly refers to the minimum vegetation productivity at a particular site in a year and is an important factor affecting species’ access to food and habitat. Seasonal variation in productivity is evaluated for the environmental stability hypothesis and indicates the seasonal variation in plant productivity, an indicator sensitive to extreme changes in vegetation productivity. Dynamic habitat indices are better predictors of species diversity and ecosystem diversity, provide usable information for biodiversity and natural resource monitoring and management, and have promising applications in biodiversity conservation.

Key words: fraction of absorbed photosynthetically active radiation (fPAR), cumulative annual productivity, annual minimum productivity, seasonal variation