基于TM影像的银川平原湖泊湿地景观空间格局动态演化研究

Abstract

区域生态安全是区域可持续发展的基础，银川平原湖泊湿地对于宁夏沿黄经济区、中国西部生态安全的维护具有十分重要的意义。本研究应用3S技术以及景观空间格局指数方法，利用1987、1997、2004和2012年四个年份的遥感影像，对1987~2012年25年间银川平原湖泊湿地进行了动态演化研究。分析得出：1) 近25年来，银川平原湖泊湿地景观斑块数量N、总面积A总、斑块最大面积Amax、斑块最小面积Amin、斑块平均面积A、平均周长L等特征整体呈增加的趋势；2) 银川平原湖泊湿地景观内部结构中,虽然部分指标特征有所改 善，但整体仍呈脆弱化、不稳定化的变化趋势，如2012年FD、D、FN、D等指数特征虽都明显好于1997年，但是与1987年状态相比仍有差距；3) 银川平原湖泊湿地景观动态演化的驱动力因子有气候和水文的自然因子以及工业发展和农业开发活动等人为因子，其中人为因子为主要的驱动力因子。根据结论进一步提出对策及建议，以期为银川平原生态建设和生态安全维护提供参考。 The regional ecological security is the basis of sustainable development, and the lake wetland in Yinchuan Plain (Ningxia, China) is of great importance for maintaining regional ecological security in the Yellow River Economic Zone in Ningxia and Western China. This study uses 3S technologies, i.e., remote sensing, geographic information sys-tem and global positioning system, to outline the dynamic evolution of lake wetlands in the Yinchuan Plain based on remote sensing images obtained from 1987 to 2012. The results are as follows: 1) The characteristic values, such as the landscape patch number, the total areas, average and maximum areas of the lake wetlands in Yinchuan Plain, i.e., are in a gradual increasing trend since recent 25 years; 2) The internal hierarchical structure of the lake wetlands in Yinchuan Plain is improved in some aspects, but the overall hierarchical structure is still fragile and unstable, for example, some characteristic indexes, such as the FD, FN and D, were obviously better in 2012 than that in 1997, but there were still some gaps compared with that in 1987; 3) The driving forces resulting in the dynamic evolution of the lake wetland landscapes in Yinchuan Plain include both the natural and artificial factors, such as the climate change, hydrological process, agricultural and industrial development activities, i.e., in which the artificial factors are dominant. According to the conclusions, some measures and suggestions are put forward, which can be referred in the ecological construction and the maintenance of ecological security in Yinchuan Plain.