基于最佳分析粒度的巴彦县土地利用景观空间格局分析

Land-Use Spatial Analysis for Bayan County Based on Optimal Grain Size

适宜的分析粒度是保证土地利用景观格局分析准确的重要环节。本文以黑龙江省巴彦县为研究区,应用遥感、GIS手段及景观指数法,探讨景观指数随分析粒度变化效应,综合面积精度损失评价,确定最佳分析粒度。从景观要素空间组成、空间形态、空间关系及空间构型4个方面分析研究区土地利用景观空间格局。结果表明:部分景观指数与粒度可拟合为数学函数关系,并确定最佳分析粒度为100m;研究区主要土地利用景观类型为旱地和林地,旱地景观优势明显,是基质景观;水域空间形态最复杂,林地、旱地等农业用地景观形状较不规则,建设用地和园地形状最简单;旱地、建设用地分布很均匀,水田、其他用地分布较合理,各乡镇间林地、草地及水域分布差异较大,园地分布差距极悬殊且斑块间分布离散;景观整体主要由团聚的大斑块组成,异质性小,形状复杂程度适中,破碎化程度不严重,稳定性差,不利于现状土地利用景观空间格局的维持。

It is very important that an appropriate grain size is selected to accurately analyze land-use landscape patterns. We used Bayan County as the study area and RS, GIS and Fragstats3.3 to explore landscape index characteristics with grain size change and the area loss, ultimately determined the optimal grain size for analyzing land-use landscape pattern. We considered four aspects of landscape elements： spatial pattern, spatial form, spatial relations and spatial configuration. The results showed that some landscape indices and grain size could be fitted to a mathematical relationship, and determined the optimal grain size for 100m. Dry land and woodland were the main land-use landscape types across the study area, especially dry land had a clear advantage. Water was the most complex spatial form; woodland and dry land and other agricultural landscape of irregular shape, construction land and garden plots were the simplest shaped due to human interference. Dry land and construction land were evenly distributed; paddy field and other land of a more reasonable distribution, woodland, grassland and water in each township had a large distribution difference. The whole landscape was of small heterogeneity and composed of large patches. The shape complexity was moderate, the degree of fragmentation not serious and landscape stability poor.