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土壤的时空变异是土壤特性的测定及建模过程中需要考虑的土壤性质。为了探明栗钙土硬度的空间分布类型及其变异规律,我们用日本藤原制作所产土壤表面硬度计测定了蒙古高原上草地典型栗钙土、暗栗钙土及沙质栗钙土的表层土壤硬度,比较研究了围封禁牧20多年硬度基本处于原始状态下的土壤,与持续过度放牧干扰后硬度增加了2~3倍的土壤和曾经过度放牧、现在禁牧后硬度下降的土壤的硬度及其变异特性。结果表明:栗钙土的土壤硬度的标准差与其平均值之间具有极显著的正相关关系;尽管干扰变化后土壤的硬度发生了很大的变化,但土壤硬度的变异系数却变化很小(<0.5倍),土壤硬度发生变化后,土壤硬度的极值、中值、极差和标准差都变化了相同的比例。无论高硬度土壤还是低硬度土壤,其空间不同样点上的测定值的统计分布均服从正态分布。自相关分析表明,高硬度与低硬度典型栗钙土沿南北方向的空间自相关距均为2.3m左右,高硬度和中硬度沙质栗钙土的自相关距分别是1和2m左右。其它各样地在大于1m的几米范围内没有明显的相关距。这表明外界均匀干扰引起的土壤硬度的变化,对土壤硬度的空间分布类型没有明显的影响。根据方差和平均值的定律推断,(1)在受到放牧干扰后,土壤硬度的标准差与平均值变化了相近甚至相同的倍数;(2)如果两点间的土壤受到相同强度的干扰,这两点间土壤硬度的差值将与两点间硬度的平均值变化相同的倍数;(3)土壤硬度可能发生倍乘变化,即一定条件下,一定强度的干扰将会使土壤硬度变化一定的比例;(4)空间不同位点上的土壤硬度具有协比变化的特性。这些均是土壤性质秩序稳定性的决定条件。
Spatial and temporal variability of soil is the determination of soil properties and the nature of the soil to be considered in the modeling process. In order to find out the spatial distribution type and variation law of the hardness of chestnut soil, we measured the surface layer of the typical chestnut soil, dark chestnut soil and sandy chestnut soil in the grassland of Mongolia Plateau with soil surface hardness tester Soil hardness was comparatively studied. Soil with banded grazing for more than 20 years under the original condition of hardness was comparatively studied. The hardness of soils which had been increased by 2 ~ 3 times after continued overgrazing disturbance and the past grazing. And its variation characteristics. The results showed that there was a significant positive correlation between the standard deviation of soil hardness and the average value of soil hardness of chestnut soil. Although the hardness of soil changed a lot after disturbance, the coefficient of variation of soil hardness changed little <0.5 times), soil hardness changes, the extreme value of soil hardness, median, range and standard deviation have changed the same ratio. The statistical distributions of measured values at different sampling points in space both obey the normal distribution in both high-hardness soil and low-hardness soil. Autocorrelation analysis showed that the spatial autocorrelation distance of typical chestnut soil with high hardness and low hardness both along the north and south direction was about 2.3m, and the self-correlation distances of high and medium hardness chestnut soil were 1 and 2m respectively. There are no other significant correlations within a few meters of more than 1 m. This shows that the change of soil hardness caused by uniform external disturbance has no obvious effect on the spatial distribution of soil hardness. According to the law of variance and average, (1) the standard deviation of soil hardness changes with the average after the disturbance of grazing is similar or even the same multiple; (2) if the soil between two points is disturbed by the same intensity, The difference between the soil hardness of the two points will be the same as the average change of the hardness between the two points; (3) the soil hardness may occur multiplied change, that is under certain conditions, a certain intensity of disturbance will make the soil hardness change a certain Ratio; (4) the soil hardness at different sites has the characteristics of co-ordinate change. These are the conditions for the orderly stability of the soil nature.