为更精确的研究区域景观要素的空间布局及其相互作用关系,选择小尺度的岔口小流域为研究对象,以2013年1∶10 000岔口小流域景观组分类型现状图为基础,通过GIS平台及FRAGSTATS 4.0软件,选取多种景观破碎化指数,对该流域的景观格局破碎化现状进行分析.结果表明:(1)林地、草地、耕地是流域最主要的景观,而园地、居民点、水域在全区呈补丁状分布;(2)沟坝地斑块数多、密度最大,破碎化最严重;(3)耕地、园地、居民点、水域的连通性差,被分割度高,破碎化严重;(4)全区景观边界褶皱度低.调整土地利用方式,整合地块,提高斑块连通性,是改善现状的重要措施.
Methods of literature and comparative analysis were used to conduct a comprehensive literature review on the influential effects and countermeasures of cultivated land fragmentation. The results showed that the effects of cultivated land fragmentation performed in agricultural planting structure, grain output, efficiency of production technology,labor force, land use pattern, land market and the other aspects, but generally its negative effects were more outstanding.Different regions made efforts to cope with the problems of cultivated land fragmentation from three main aspects including rural markets, comprehensive rearrangement of land and the legal system. Based on the cultivated land ecological stability and broad public participation, it was important to solve the problem of cultivated land fragmentation for improving the sustainable development of agriculture and farmers' living.
以岔口小流域为研究对象,基于耕地现状和权属数据,借助GIS技术与FRAGSTATS 4.0软件,分析不同耕地类型破碎化的内部差异性,为未来的土地整治及农业规模化经营服务.结果显示,耕地的权属破碎化大于自然破碎化,总体破碎化程度表现为沟坝地>坡耕地>沟川地>梯田;空间分布上呈现为:梯田大面积集中于北部村庄,沟坝地、沟川地沿沟河呈条带状延伸,坡耕地则呈小片状分散布局;耕地适度破碎化益于水土保持,辩证地分析各耕地类型破碎化的影响效应利于土地整治的开展;4种耕地类型的边界褶皱度低.该区应因地制宜地开展土地整治及规模化经营.
Using RUSLE model to simulate and evaluate soil erosion respectively in the research area of 1998 and 2008. Based on analysis the study area soil erosion spatial and temporal variations in 10 years with the perspective of using landscape ecology is presented. The results are as follows: ①the majority of soil erosion are slight moderate in study area,the slope area,at an altitude of 250m above 8°~ 15° region is the main area of high soil erosion risk. Soil erosion in the study area is significantly higher than the upstream,midstream and downstream. ② the study area soil erosion area significantly reduced,erosion amount reduced,where severe erosion rate,up to 46. 36%. ③ showed that the study of small watershed in different time of the agricultural landscape pattern and the relationship between the soil erosion,2008 soil erosion and landscape index corresponding to the single factor correlation are higher than in 1998,indicating that the human intervention is the main reason of soil erosion reduction.
Temperature-Vegetation Dryness Index(TVDI) is an inversion analysis method for soil water content in vegetation coverage area based on optical and thermal infrared remote sensing channel data.The traditional TVDI model does not consider the affects of surface energy balance factors on the surface temperature(Ts) and the atmosphere and the soil background on vegetation index.Firstly,the impacts of topography and differences of cover types on Ts were eliminated using Digital Elevation Model(DEM) image.Secondly,the correlation between the measured soil moisture content and different TVDI index models such as Ts/RVI,Ts/NDVI,Ts/EVI and Ts/MSAVI was analyzed.Then,choosing the model of Ts/MSAVI,of which correlation is the highest,to invert moisture content in soil.Finally,the results indicated that the Ts/MSAVI model can estimate the soil moisture content in Dongliaohe basin effectively.