东洞庭湖保护区1989～1998年水禽栖息地动态研究

Dynamics of waterfowl habitats in the Eastern Dongting Lake Nature Reserve between 1989 and 1998

栖息地的改变是全球生物多样性存在的最大威胁。利用卫星遥感技术和地理信息系统的空间分析功能,从景观尺度上研究了东洞庭湖自然保护区1989～1998年越冬水禽栖息地的动态变化特征,结果表明:1989～1998年水体、泥滩地、草滩地和水田等水禽适宜栖息地的面积在减小,破碎化程度有所增加,而芦苇滩地、旱地、林地、建成区这几类水禽分布较少栖息地类型的面积和破碎化程度的变化正好相反;近10年来水禽栖息地的变化比较明显,其中草滩地演变为芦苇滩地及水田改为旱作农田的变化最为突出,变化的面积分别占整个保护区面积的10.66%和6.13%。这些变化趋势意味着研究区近10年来水禽的适宜栖息地在退化。针对变化的原因,论文还对该区域生物多样性的保护与栖息地管理提出了可行的建议。

Habitat alterations remain the greatest threats to the world’s biodiversity.This study characterized the dynamics of waterfowl habitats at landscape scale in the Eastern Dongting Lake Nature Reserve between1989-1998by using satellite remote sensing techniques.Landsat TM satellite images for1989and1998were classified and analyzed.The waterfowl habitats were grouped into eight types:water body,mudflat,sedge land,reed land,paddy field,dryland,forest and settlement.By applying geographic information system(GIS),patch-related landscape indices were generated and the spatial patterns of waterfowl habitat changes over the10-year period were analyzed.The study indicates that the area of the suitable habitats for waterfowl,such as water body,mudflat,sedge land and paddy field decreased,while the fragmentation of these suitable habitats increased between1989-1998,which was indicated by a decreased mean patch size.The changes in the area and fragmentation of the unsuitable habitats for waterfowl such as reed land,dryland,forest and settlement showed a different pattern.The analysis also suggests that great changes in waterfowl habitats had happened during the past10years,the highest change rates were from sedge land to reed land and from paddy field to dryland,which were10.66%and6.13%of the total area of the Nature Reserve,respectively.The above-mentioned dynamics of waterfowl habitats between1989and1998suggests that the suitable habitats for waterfowl in this study area degraded.This study also proposed feasible suggestions on the biological conservation and habitat management through analyzing the reasons that caused the degradation of the suitable habitats for waterfowl.