莲花湖库区落叶松水源涵养林土壤入渗性能的空间分布特征

以莲花湖库区落叶松水源涵养林为研究对象,由入渗速率拟合入渗模型,运用地统计学理论与方法对模型参数进行空间异质性分析。结果表明:采用Philip公式对入渗过程进行数学模拟最佳,模型参数吸渗率和稳渗率均服从对数正态分布,空间相关性强,结构比分别为0.867、0.759,变程分别为29.13 m、6.16 m,分维数分别为1.786、1.970。两者块金值都很小,小尺度内非连续性变异不明显,空间分布格局相类似,空间自相关范围内呈极显著正相关关系,相关系数R为0.48。二者相比,吸渗率空间自相关尺度大,空间分布较简单;稳渗率均一性差,空间分布复杂,破碎化程度高。

Spatial Distribution Characteristics of Soil Infiltration Capacity in Water Conservation Forest of Larix gmelini in Lianhua Lake Reservoir Area

Water conservation forest of Larix gmelini in Lianhua Lake reservoir area was regarded as research objects. Soil infiltration model firstly was fitted by the rate of soil infiltration speed, and spatial distribution characteristics of the parameters of infiltration model were analyzed by geostatistical method secondly. The results showed: Philip infiltration model has better analog calculation effects on mathematical simulation of soil infiltration than other models. Soil suction rate and steady infiltration rate obtained by fitting both show lognormal distribution and have strong spatial dependence. The proportion of the former is 0.867, and that of the latter is 0.759. The effective range of the former is 29.13 m, and that of the latter is 6.16 m. The fractal dimension of the former is 1.786, and that of the latter is 1.970. Both semivariogram nuggets are small, and the discontinuous variation on small scale isn’t obvious. There is a high significantly positive correlation between the spatial distribution pattern of soil suction rate and that of steady infiltration rate, and the correlation coefficient R is 0.48 within spatial autocorrelation range. By comparison between two parameters, soil suction rate has large spatial correlation range and simple spatial distribution;but steady infiltration rate has unconspicuous homogeneous character, complex spatial distribution and high degree of fragmentation.