An index of human influence on natural environments: based on population density, land transformation (leading to loss and fragmentation of habitats), human access, and power infrastructure. See Sanderson et al. (2002) Bioscience 52, 10.
科学参考收录了60776条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。