甘肃临泽荒漠景观的空间结构与生产特性

Landscape Pattern and Its Productivity of the Desert Landscape Ecosystem in Hexi Corridor of Gansu

采用GIS技术对甘肃临泽荒漠景观的空间结构与生产特性进行了研究。研究结果表明:荒漠临泽景观生态系统由砾漠、沙漠、岩漠、道路4种景观组分组成;其中砾漠的面积最大,连通性最好,是荒漠景观生态系统的基质,道路为仅有的1种廊道,廊道密度为37.66m/km2;岩漠和沙漠是荒漠景观中的两种斑块类型;基质的成因类型为环境资源型,斑块的成因类型可以分为2类:岩漠为残留型,沙漠为干扰型。在生产能力方面,砾漠的地上生物量砾漠最高,是岩漠的6.89倍、沙漠的28.81倍;岩漠次之,其地上生物量仅为砾漠的14.51%,是沙漠的4.18倍;沙漠的地上生物量最低,分别是砾漠、岩漠的3.47%、23.91%。在植物学成分方面,三者的差异不显著,但由于水、热因素的分布差异,植被密度的差异巨大,形成了生产力水平差异的基础。

This paper studies on space structure and productivity characteristic of desert landscape in Linze using GIS. The results show: the desert landscape ecosystem of Linze is made up of 4 foundational elements including rocky desert, sandy desert, conglental desert and road. Among them, conglental desert has the largest area and highest connectivity, so it is the matrix of the desert landscape ecosystem; road is the only one kind of corridor, its corridor density is 37.66 m/km2; rocky desert and sandy desert are two kinds of patch types. The genetic type of matrix is belong to environment resource type, and the genetic type of patches have 2 types: rocky desert is rudimental patches type and sandy desert is disturbance type. For the productivity, rocky desert has the highest above ground biomass, which is 6.89 times of conglental desert, 28.81 times of sandy desert; the above ground biomass of conglental desert is about 14.51% of rocky desert, and is 4.18% times of sandy desert; sandy desert has the lowest above ground biomass which is 3.47% and 23.91% of rocky desert and conglental desert respectively. The differences vegetation types in different desert are not obvious, but due to the great differences in the variation of local water and heat, the plant density changes greatly, resulting in the significant difference in their productivity.