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资源科学 2008
Geostatistical Analysis of Human Impact Indexes for Land Use/Cover Change in Fujian
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Abstract:
Land use/cover change (LUCC) is an important component of global change research, and the driving forces of LUCC are one of the main topics of research, including both biophysical and socioeconomic factors. Because of the widespread occurrence of spatial autocorrelation, applying linear spatial information statistics to analysis of settings with randomness and unknown structures will lead to significant errors. Geostatistics are an important tool for spatial analysis, and have been applied to many fields of natural science such as geography, ecology, and soil science. This study uses data from TM images from 1985 and ASTER images from 2002 of Fujian. We then constructed human impact indexes, compiled the land use/cover human impact index maps for 1985 and 2002 and the land use/cover human impact index change map from 1985 to 2002, and calculated the temporal and spatial variability. The results show that the human impact indexes for 2002 have directionality which is consistent with the topography and the coastline, and trends of the five general land use/cover types and all of the regional land use types are approximately NNW-SSW using Standard Deviational Ellipse. The structural factors are mainly natural ones, with terrain roughly in the shape of a staircase, declining from the northwest to the southeast in strips of mountains, hilly lands, terraces and plains. In total, 87.5% of the province is covered with mountains and hilly land. The mountain areas are mainly in the Daiyunshan mountain range and Wuyishang mountain range, which are more or less parallel to the coastline. The terrain affects the properties and development of soil and vegetation. The proportion of structural variance is 88.92% and the proportion of nugget variance is 11.08% with strong spatial correlation, and the structural factors are the dominant component of the LUCC spatial distribution pattern. The change in human impact index from 1985 to 2002 deviates with the topography and the coastline, which means there are other relevant factors besides terrain. The proportion of structural variance is 18.07% and the proportion of nugget variance is 81.93% with weak spatial correlation, which means the natural factors don't play a decisive role in the human impact index change the way that human factors do. Commonly, the structural factors are the dominant cause of spatial variability while the human factors are the dominant influence on temporal variability.