我国青海省嵩草草甸地上净生产量的空间变化特征

THE CHARACTERISTICS OF SPATIAL VARIATION OF KOBRESIA MEADOWS IN QINGHAI PROVINCE OF CHINA

应用地统计学方法,结合青海省嵩草草甸地上净生产量及环境因子的相关数据,从空间自相关关系以及变异函数入手,对其空间分布特征进行了分析和讨论.结果表明,青海省嵩草草甸地上净生产量的空间分布呈明显的带状异向性,空间分布的变化与所研究的尺度和方向紧密联系.对环境因素的分析表明,该区年降水量的空间分布特征与嵩草草甸地上净生产量的分布在各向同性(isotropic,ISO)以及2个主要方向上的各向异性的变化均相一致.因此,在开发和利用嵩草草甸这一牧场资源时,应考虑其空间分布特点.

Kobresia meadow belongs to the alpine cold meadow. It is mainly distributed in Qinghai-Tibet Plateau in China. The meteorological conditions and the degrees of spatial heterogeneity in the area are very complex. The relationship between the above-ground net production and the environment factors is analyzed by using geostatistical methods, such as autocorrelations index, semivariariance analysis, fractal dimension etc.. The results show that the above-ground net production of Kobresia meadow has a obvious zonal anisotropy. It is greatly correlated with spatial scale and the direction, i.e. the spatial autocorrelations being positive in small scale, negative in mid-scale, and with great variation in large-scale. There are many factors affecting the above-ground net production of Kobresia meadow. The results show that the spatial variation of annual precipitation is in agreement with the above-ground net production. The spatial variation of the Kobresia meadow when exploiting these meadow resources should be considered.