Spatio-Temporal Variation of Vulnerability of Landscape Ecology of Caohai Wetland

The research on ecological vulnerability, as a hot spot and important orientation of the study on ecology, is of important guiding significance to regional environmental protection, rational planning and utilization of land resources and sustainable development. Landscape vulnerability index was established based on 3S technology and theories and methods of landscape ecology for analysis of characteristics of the variation of landscape pattern and landscape vulnerability in the study area as a whole. To proceed with relatively small scaled controllable unit, 53 administrative villages in the studied area were used as evaluation units to explore characteristics of the variations of landscape ecological vulnerability and its spatiotemporal distribution in the Caohai Wetland. Results show:(1) During the period from 1995 to 2015, woodland and grassland decreased much in area, while construction land and water surface kept on increasing. Landscape vulnerability index of the study area expanded gradually in the past 20 years, but in terms of vulnerability index, the fractions of the landscape remained almost unchanged, i. e. grassland > woodland > cultivated land > construction land > water surface; (2) During the period from 1995 to 2015, villages high and moderate in landscape vulnerability were concentrated mainly around the study area and decreasing in number, while villages, so so and potential in landscape vulnerability were mostly in the central part of the study area and increasing in number; (3) The ecological vulnerabilities of the villages exhibited significant autocorrelations, but spatial agglomeration of the villages similar in landscape vulnerability declined somewhat; and (4) The spatial distribution of landscape ecology vulnerability of the administrative villages was shifting from the low-low type of agglomeration to the high-high type and most of the villages no longer exhibited much spatial autocorrelation, and no low-high type of agglomeration appeared.