喀斯特山区植物物种丰富度的空间变异分析

Analysis on Spatial Variability of Plant Species Richness in Karst Mountanes Area

摘要:

应用地统计学对地处滇黔桂连片喀斯特腹地的贵州省毕节地区植物物种丰富度的海拔空间变异进行分析。结果表明, 乔木物种丰富度的半变异函数最佳理论模型为球状模型, 灌木、草本为线性有基台模型。乔木物种丰富度的空间异质比为0.0052, 具有强烈的海拔空间相关性, 主要受随海拔梯度变化的自然性控制因素的影响; 灌木、草本物种丰富度的空间异质比分别为3.15、34.55, 海拔梯度的空间相关性很弱, 受随机因素作用较大。乔木物种丰富度的变程为177.37 m, 受因素影响的海拔范围较宽；灌木和草本物种丰富度的变程分别为73.02 m和49.97 m, 受因素影响的海拔范围较窄。灌木、草本物种丰富度的Moran’s I系数随海拔梯度变化的趋势相类似, 但乔木的差别较大。

Abstract:

The spatial variability of plant species richness was analyzed using geostatistics in the Karst area of Bijie, Guizhou Province, which presents wide altitudinal range in southwest China. The optimal semivariogram theoretical model fitted for arbor species richness was spherical model, and the linear sill model for shrub and herb. The arbor species richness was highly related to altitudinal gradient with a spatial heterogenous rate of 0.0052, which mainly affected by natural controlling factors with altitudinal variation. Shrub and herb species were mainly affected by random factors, which showed very weak relationship with altitudinal gradient and their spatial heterogenous rates were 3.15 and 34.55, respectively. The altitudinal range of arbor species richness was 177.37 m, which indicated a wide altitude range affected by random factors. The altitudinal range of species richness of shrub and herb were 73.02 m and 49.97 m, respectively, which indicated a narrow altitude range affected by random factors. The changes of Moran’s I index of shrub and herb species along altitudinal gradient were similar that were different from that of arbor species.