河南省土地覆盖变化的时空特征分析

以遥感与GIS为技术支撑,对河南省20世纪80年代至2005年的土地覆盖进行了动态监测,并分析了土地覆盖变化的时空特征及其驱动因子.监测结果表明,河南省土地覆盖变化的时空特征为:(1)变化数量.城镇建设用地显著增加,内陆水体面积增加明显,农村聚落和落叶阔叶林有所增加,常绿阔叶林略有增加;灌丛草地、水浇地、旱地和河湖滩地面积减少明显.(2)变化速度.城镇建设用地面积增速迅猛,内陆水体增速明显;沙地面积减速最快,裸地、沼泽和草甸草地减速较快,河湖滩地和灌丛草地减速明显,旱地和水浇地面积减速较小.(3)空间转换.以农田和聚落之间的转换为主,另外城镇建设用地的增加包括其扩展融人的农村聚落等;内陆水体增加主要由河湖滩地转变的;灌丛草地减少主要转变为旱地.驱动力分析表明,区域自然因素相对稳定,对土地覆盖变化的影响较小,而人口增长、经济发展、农业结构调整、政策和交通等社会经济因素是河南省土地覆盖变化的主要驱动力.河南省土地覆盖变化的总体特征与区域经济发展、产业布局及其工业化、城市化演变的特征十分吻合.

Spatiotemporal Characteristics of Land Cover Change in He' nan Province

Land cover of He'nan Province had been monitored from 1980s to 2005. Based on remote sensing and GIS technique,the analysis on the spatiotemporal characteristics of land cover change and driving factors was made. Results show (1) Change area:The areas of urban and build up type of land cover were increased observably and the area of water body also had an obvious increase. The areas of rural settlement and deciduous broadleaf was appreciably increased and the area of evergreen broadleaf had a slight increase. On the other side,the areas of shrub grassland,irrigated cropland,unirrigated cropland,and bottom land had an obvious decrease. (2) Change speed:Urban and build up type had a very sharp increase slope and water body had second fast increase speed. The sort order of decrease speed from maximum to minimum is:sand land,bared land,marsh,meadow grassland,bottom land,shrub grassland,unirrigated cropland,and irrigated cropland. (3) Spatial conversion:The spatial conversion mostly occurred between cultivated land and settlement. Additionally,the increase of urban and build up type included the rural settlements assimilated by urban. The part of water body increase was mainly converted from bottom land and shrub grassland was mainly converted to unirrigated cropland. The natural environmental factors were stable and less important to the change of land cover. However,population,economy,adjustment of agricultural structure,policies,and transportation play the fundamenta1 roles in land cover change. The concurrent correlation analysis indicates that the most important driving factors of land cover change in He'nan Province are rapid economic development and accelerated urbanization process.