为了给江苏盐城海滨区域的生态环境管理提供理论和技术支持,利用地统计学理论模型和GIS技术,对江苏盐城海滨区域3个时期的土地利用和景观数据进行了生态风险评价和空间变异分析。研究结果显示:1987~2007年,盐城海滨区域和自然保护区内的土地利用结构均发生了显著变化,耕地逐渐增加,自然湿地迅速减少、人工湿地逐渐增加,人类对湿地景观的干扰程度逐渐加剧。自1987年以来,盐城市海滨区域的生态环境受人类活动的干扰增强,景观破碎化程度加剧,景观结构的变化已导致景观生态风险指数发生了显著的时空差异,景观生态风险呈增大的趋势。20a间,盐城市景观生态风险的空间变异程度逐渐增大。1997年随机地域的空间异质性最大,景观生态风险的空间相关程度最大。盐城市海滨区域的景观生态风险的空间异质性(自相关)尺度和方向性也发生显著变化。各时段该区域东西方向上的变异大于南北方向上的变异;在东西方向上,景观生态风险强度呈现由低变高,而后又降低的特点,最高风险强度带位于西部农田与东部光滩沼泽交界的过渡地带。
With the geo - statistical theoretical model and GIS technology, three periods of landscape data from 1987 to 2007 in Yancheng coastal area were assessed for ecological risk and analyzed for spatial variability. Some conclusions have been reached: ① With the growing intensity of human activities in coastal wetlands, the size of natural wetlands gradually decreased, and the disturbance gradually increased in coastal area. ② The ecological environment of this area was subjected to increased interference of human activity and landscape fragmentation from 1987. The change of landscape structure led to significant differences in risk indexes of landscape ecology in time and space. The landscape ecological risk of Yancheng coastal area tended to expand. ③ The degree of spatial variability increased in these 20 years. In 1997, spatial heterogeneity of random party was the largest, and the space - related degree was the largest in landscape ecological risk. ④ From 1987 to 2007, the scale and direction of spatial heterogeneity (autocorrelation) of landscape ecological risk in Yancheng coastal area also changed significantly. (~) In each period, the variation in EW direction was larger than that in NS direction. In EW direction, the intensity of landscape ecological risk changed from low to high and then to low again.