杉木拟赤杨混交林土壤肥力性状研究

A Study on Soil Fertility Properties under Mixed Forest of Alniphyllum fortunei and Chinese Fir

通过对 1 1年生杉木拟赤杨混交林土壤肥力测定结果表明 :杉拟混交林土壤结构体、孔隙状况、水分状况和土壤化学性质均较杉木纯林有所改善 ;各模式 0～ 2 0cm土壤 >0 .2 5mm的水稳性团聚体含量比杉木纯林提高 6.2 1 % ;总孔隙度和通气度分别较杉木纯林增加 9.87%和 1 8.0 6% ;杉拟 3∶1混交林 0～2 0cm土层的最大持水量、毛管持水量和最小持水量比杉木纯林分别提高了 1 1 .96% ,2 0 .5 5 % ,2 2 .46% ;各模式土壤养分含量有所提高 ,杉拟 3∶1混交林土壤有机质比杉木纯林提高 43 .96%。这说明通过落叶阔叶树和常绿针叶树之间的混交具有较强的培肥土壤和水源涵养作用 ,对防止杉木多代连栽造成的地力衰退问题具有重要的指导意义。

The soil fertility under the mixed forest of Alniphyllum fortunei and Chinese fir was tested. The results were as follows :Soil structure, porous property, soil water and chemical properties were better than those under pure Chinese fir forest. In the 0～20 cm soil depths, in all the proportions, the waterstable aggregation(d>0.25) was improved by 6.21% compared to that under the pure fir forest. The total porosity and aeration increased by 9.87% and 18.0% .In the 0～20 cm soil depths under the mixed forest(Chinese fir 3∶ Alniphyllum fortunei 1), by contrast with those under the pure Chinese fir, maximal water-holding capacity , porous water-holding capacity and minimal water-holding capacity increased by 11.96% , 20.55% and 22.46% respectively. The soil nutrient content was increased to a certain extent in all the mixed proporions, and soil organic matter under the mixed forest(Chinese fir 3∶ Alniphyllum fortunei 1) was improve by 43.96% . At the same time, these data showed that the mixture of deciduous broad-leaved sperms/evergreen conifer forest could enhance soil fertility and has water-conservation effect. Furthermore, the mixed forest could prevent the decline of soil fertility due to multigeneration plantation of Chinese fir.