基于灰色关联分析的杉木连栽林地土壤水分物理性质研究

Research on Soil Moisture Physical Characteristics of Cunninghamia lanceolata Plantations under Different Rotations of Continuously Planting in Guangxi Based on Gray Correlation Analysis

选取广西杉木连栽一代林（G1）和二代林（G2）土壤的容重、孔隙度、持水量和贮水量等11个物理性质作为参评对象,利用MCEGray软件计算出广西杉木幼林不同栽植代数、不同土层深度土壤水分物理状况的关联度及大小排名。分析结果表明：1）G1,G2的土壤容重均随深度的增加而增加,随着栽植代数的增加,土壤容重趋于减少;2）随土层深度的增加,G1,G2的总孔隙度、毛管孔隙度、饱和持水量和毛管持水量均逐渐增加;3）杉木林在0-40cm土层中,G2林地土壤物理性质优于G1林地,G2的土壤保水能力较G1强,但G2的涵养水源能力比G1弱;4）土壤容重对土壤水分物理状况的影响最为重要,连栽杉木人工幼林林地的水分物理状况水平排列顺序为G2（0-20cm）〉G2（20-40cm）〉G1（0-20cm）〉G1（20-40cm）。

In order to provid a reliable basis in theory for sustainable management and sustainable nutrient management of successive planting of Cunninghamia lanceolata plantations in Guangxi Zhuang Autonomous Region,the eleven evaluation objects（such as soil bulk density,soil porosity,soil water retaining capacity and soil water storage etc.）were selected as the research objects,and modern comprehensive evaluation software of AHP module was used to calculate and analyze the correlation degree and size ranking of soil moisture physical condition of Cunninghamia lanceolata plantations under different plantings（G1 and G2）and different soil thickness（0 -20cm and 20 -40cm）.The results showed that：（1 ）The soil bulk density of Cunninghamia lanceolata plantations under different rotations increased with the increment of soil depth.The soil bulk density of soil were greatly reduced by the continuous cropping of Cunninghamia lanceolata.（2）With the increment of soil depth,total porosity,capillary porosity,saturated moisture capacity,capillary holding capacity increased gradually.（3 ）In the layer of 0-40 cm,the soil total and uncapillary porosity of the second generation forest was larger than the first one,soil water retention capacity of the second generation forest was stronger than the first one,but the former was weaker. （4） The effect of soil bulk density on soil moisture physical condition was the most important,and the order of soil moisture physical condition in the field of successive planting Cunninghamia lanceolata was G2（0-20cm）〉G2（20-40cm）〉G1 （0-20cm）〉G1 （20-40cm）.