基于Meta分析的中国北方植被建设对土壤水分影响

Influence of vegetation construction on the soil moisture in northern China: A meta analysis

植被建设是中国北方干旱半干旱地区防治风蚀和水蚀的最为有效手段,而合理的植被建设需要考虑土壤水分的植被承载力。在收集有关中国北方干旱半干旱地区植被建设后土壤水分研究文献的基础上,采用Meta分析研究了该地区植被建设(乔木和灌木)对土壤水分的影响。结果表明:北方干旱半干旱地区植被建设总体上对深层(40 cm以下)土壤水分含量产生显著降低作用(结合效应值为-0.40);乔木栽植导致土壤水分含量大幅度降低(-0.58),灌木栽植也在一定程度上导致土壤水分含量降低(-0.27),但其影响不显著;亚组分析表明,建植年限<20 a的乔木以及栽植在降雨量超过400 mm以上地区的乔木是导致土壤水分含量显著降低的主要因素(其结合效应值分别为-0.62和-0.69);因此,乔木栽植对于土壤水分的消耗大于灌木,在该地区开展灌木栽植能够有效提高土壤水分利用效率。

Vegetation construction is the most effective way to control erosion by wind and water in the arid and semi-arid regions of northern China. Reasonable vegetation construction needs to consider the vegetation carrying capacity of soil water. Based on published literatures of soil water change following revegetation in the arid and semi-arid regions of northern China, this paper analyzed the influences of two kinds of vegetation construction （ trees and shrubs） on soil water at different depths using a meta-analysis. The results showed that vegetation construction produced prominent negative effects on soil water in deep layers （below 40 cm, with an effect size of -0.40）. Tree planting resulted in a significant decrease in soil water （effect size： -0.58）, while shrub planting had a negative effect on soil water （ effect size ： -0.27 ） though no significant influence was found. According to the subgroup analysis, tree plantations in the zones with precipitation of more than 400 mm and with the stand ages of less than 20 years led to decline of soil water （effect sizes： -0.62 and -0.69, respectively）. The results indicated that tree planting produced more negative influences on soil water environments than shrub planting, and shrub planting could improve soil water-use efficiency in the arid and semi-arid regions.