洋河小流域土地利用景观空间格局垂直变化

以洋河小流域为研究对象,在地理信息系统软件MapGIS和arcview3.3以及景观格局分析软件fragstats的支持下,选取斑块类型面积、分形维数、多样性、均匀度、优势度、蔓延度、散布与并列等指标,对洋河小流域土地利用与景观格局的垂直变化进行研究.结果表明,洋河小流域的土地利用结构呈现出明显的垂直变化规律.各种土地类型的绝对数量在区域的低海拔段占绝对优势,随着海拔的升高,耕地、水域所占本高程带的百分比呈上升趋势,而林地和未利用地则呈相反趋势.园地呈现先升后降趋势,建设用地基本维持不变.土地利用影响景观格局的变化,景观格局同样呈现出明显的垂直分异规律.林地、未利用地和园地的分形维数呈现随海拔升高而增加的趋势,而建设用地呈现相反趋势.由于人类干扰程度的不同,多样性指数和均匀度指数呈现先升后降,优势度指数呈现先降后升的趋势.这与蔓延度指数与散布和并列指数所体现的景观类型的团聚程度和混杂情况的变化规律相一致.

Vertical Variation Study on the Spatial Pattern of Land Use Landscape in Yanghe Small Watershed

On the basis of Yanghe small watershed,some landscape indexes were selected such as patch size,fractal dimension,diversity,dominance,evenness and contagion,using GIS software map GIS6.6,arcview3.3 and the landscape pattern analysis software fragstats.The changes of land use and the landscape pattern in Yanghe small watershed were studied under different elevation.The results showed that the land use structures obviously presented vertical differentiation rule.The amount of every land use type in lower zones was absolutely more than that of higher zones.And with the increase of height,the percentage of arable land and water area occupied this elevation belt increased,while wood land and unutilized land decreased.The orchard presented a tendency of first rise and then drop,while the construction land kept its invariability.The land use influenced landscape pattern,and the landscape pattern also obviously presented a rule of vertical differentiation.The fractal dimensions of wood land,unutilized land and orchard presented a tendency of increase with the elevation enhancement,but constructs land presented the opposite tendency.As a result of the different disturbance degree of humanity,the indexes of diversity and evenness presented first rise then fall,while indexes of dominance presented first fall then rise.This was consistent with the change rule of landscape type reunion degree and the combination situation which was presented by contagion,interspersion and juxtaposition index.