舟山岛自然栖息地的变化及其对兽类物种绝灭影响的初步研究

Changes of natural habitats on Zhouskan Island and their effects on species extinction of mammals

舟山岛自然栖息地和物种受到人类活动的强烈干扰．占总面积５６．３％的自然栖息地已经消失，自然栖息地已破碎成许多碎片，碎片面积不断变小，碎片数量在增加．自然栖息地的质量发生了很大变化．自然栖息地的易破碎带与其地理特征有关，破碎易发生于被开垦和开发的地带．由于自然栖息地面积损失、破碎、质量下降和过度捕杀，已有５种兽绝灭，３种兽正走向绝灭，绝灭速度高于临近大陆．人口增长是舟山岛自然栖息地损失、破碎、质量下降和物种绝灭的根本原因．本文还讨论了保护自然栖息地和物种多样性的一些措施和原则．

Owing to the anthropogenic disturbance, the natural habitats on Zhoushan Island, whose area occupies 56. 3% of the total, are disappeared. They are fragmented into many fragments and their quality is greatly changed. Just for these, and over-hunting, 5 species of mammals are extincted and 3 species of them are going to extinction, the extinction rate being higher than that on the continent closed by. Population growth is the main cause of the disappearance. fragmentation and quality descending of natural habitats and the extinction of mammal species. Some countermeasures and their principles for conserving natural habitats and species diversity are discussed in this paper.