西藏主要农作区土壤pH值和电导率分布特征及其相关性分析

Distribution Characteristics and Correlation Analysis between Soil pH and Electrical Conductivity in Tibet Field

本文以西藏日喀则、山南和拉萨几个主要农作区为研究对象,分析了西藏主要农作区土壤0~10、10~20和20~40 cm层次上土壤p H值和电导率分布特征及其相关性分析。结果表明,西藏农作区供试土壤均表现为碱性,且随土层加深土壤p H呈增加趋势,土壤p H值在空间分布上具有较大的稳定性,具有较小的空间变异。土壤在0~10、10~20及20~40 cm土层其p H分别为8.45±0.26、8.53±0.24和8.56±0.24,变异系数分别为3.08%、2.79%和2.81%;土壤电导率及其变异系数均表现为：0~10cm〉10~20 cm〉20~40 cm,电导率均值分别为：（1.77±1.28）、（1.50±1.05）和（1.30±0.68）us/cm,变异系数分别为：72.35%,69.89%、51.90%;回归分析表明土壤电导率与p H值之间呈负相关性,但相关性不显著,其回归方程为y=-0.0635x＋8.646（R2=0.0318）。

In this paper,taken the major farmlands（Shannan,Rikaze,lasa） in Tibet as tested objectives,the soil p H,electrical conductivity and their correlation in the different soil layers of 0-10,10-20 and 20-40 cm were analyzed. The results show that all soil samples were alkaline soil,the soil p H increased with soil layer deepening,and soil p H value had a great stability on the spatial distribution and a smaller space variation. Soil p H and variable coefficient in 0-10,10-20 and 20-40 cm layers were（8. 45 ± 0. 26） and 3. 08 %,（8. 53± 0. 24） and 2. 79 %,（8. 56 ± 0. 24） and 2. 81 %,respectively; Soil electrical conductivity and coefficient of variation were as follows：0-10 cm 10-20 cm 20-40 cm,average conductivity were（1. 77 ± 1. 28）,（1. 28 ± 1. 05） and（1. 30 ± 0. 68） us / cm,and coefficient of variation were 72. 35 %,69. 89 %,51. 90 %,respectively; The result of regression analysis performed a negative correlation between soil electrical conductivity and p H value but insignificant correlation,their regression equation was y = 0. 0635 ＋ 8. 646 x（R2=0. 0318）.