摘要
以海南岛西部地区为研究对象,选取分离度、分形维数、破碎度3个景观格局指标和土地沙化、土壤侵蚀2个敏感性指数,构建景观类型脆弱度和区域生态脆弱度模型,从景观格局与生态系统敏感性相结合角度探讨了区域生态环境脆弱性问题。结果表明:(1)研究区耕地的景观类型脆弱度最大,林地次之,水域最小;(2)相关分析显示,景观类型脆弱度与沙化敏感性、景观类型脆弱度与破碎度、破碎度与土地沙化敏感性、破碎度与区域生态环境脆弱性之间存在着显著和极显著的正相关关系;(3)区域生态环境脆弱性分区的空间分布与客观实际吻合良好,表现为:水平方向上,生态脆弱度大体平行于海岸线,呈条带状分布,离海岸线的距离越近脆弱度值越高;垂直方向上,生态脆弱度具有随海拔增高坡度变大而出现增大的趋势;(4)格局指数与区域生态环境脆弱性驱动力间的关联分析,表明琼西区域景观特征和区域生态环境脆弱性的变化主要受人类活动所调控,同时,还受控于海洋和地貌两大自然因素。区域生态脆弱性格局指标与脆弱性驱动力之间有着良好的信息反馈联系;(5)从景观视角出发,建立起景观信息与区域生态环境响应之间的联系,可以从更广、更高层面上来分析与评价区域环境问题,并为区域生态环境的建设提供新的研究方法和思路及有益的实践指导。
The ecological vulnerability of the western Hainan Island was assessed using a combined landscape pattern and ecosystem sensitivity approach. Models were developed by considering the following five factors: ( 1 ) reciprocal of fractal dimension (FD) , (2) isolation ( FI), (3) fragmentation ( FN), (4) sensitivity of land desertification (SD), and ( 5 ) sensitivity of soil erosion (SW). The major findings of this study include : ( 1 ) The vulnerability of various landscape types was in the following decreasing order: farmland 〉 forest land 〉 water area. This suggests that the ecosystems of farmland and forest land are unstable and therefore sensitive to external disturbances; (2) Significantly positive relationships were found between VI(vulnerability of landscape types)and SD, VI and FN, FN and SD, FN and EVI (regional ecoenvironment vulnerability). This suggests that FN and SD have great impacts on VI and EVI in the western Hainan Island; ( 3 ) There is a good agreement between the predicted and actual distribution of EVI zones. EVI value tends to decrease with increasing distance from the coastline and increase with increasing altitude. (4) The landscape pattern and regional ecological vulnerability in the western Hainan Island is predominantly controlled by human activities though physical factors such as topography and ocean influences also play roles in the process ; and (5) The establishment of relationships between landscape information and the regional ecological responses will offer a better way to analyze and assess regional eco- environment issues and therefore better guide the ecological construction in the region.
出处
《生态学报》
CAS
CSCD
北大核心
2007年第4期1257-1264,共8页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目(40661004)
海南省自然科学基金资助项目(8052680688)
海师青年基金资助项目(HSQN0317)~~
关键词
景观格局
敏感性
脆弱度
海南岛
生态系统
landscape pattern
sensitivity
index of vulnerability
Hainan Island
ecosystem