采伐迹地恢复阔叶林与人工栽杉土壤肥力变化差异的初步研究

本文连续3a分析比较了采伐迹地恢复阔叶林和人工种植杉木林土壤肥力变化的差异。结果表明:在人工栽杉3a内,杉木林土壤水分含量和有效水含量下降,土壤干湿交替变化增大,水分物理性状变差,土壤水稳性团聚体含量降低,结构体破坏率增大,而阔叶林则呈上升趋势。杉木林下土壤微生物数量在造林3a内呈不断下降趋势,而阔叶林则呈增加趋势;杉木林土壤氧化还原酶活性弱于阔叶林,水解酶活性强于阔叶林,两种酶系活性在3a内阔叶林增强,杉木林减弱;阔叶林土壤养分在3a内不断提高,杉木林土壤不断下降。

A PRELIMINARY STUDY ON THE DIFFERENCE OF SOIL FERTILITY CHANGES BETWEEN PLANTING CHINESE FIR AND RECOVERING BROAD-LEAVED FOREST AFTER CLEAR CUTTING

This paper deals with the study by plot experiments and measurements on the difference of soil fertility change after planting Chinese fir (Cunninghamia lanceolata )and recovering broad-leaved forest on clear cutting blank during three years. The results showed that soil moisture and available water content reduced, water-physical properties became worse, wa-terstable aggregate content turned lower and dispersion ratio of structures raised in the soil under Chinese fir plantation in comparison with those of the soil under broad-leaved forest in three years. In addition,the soil nutrients continuously decreased under Chinese fir plantation and increased under broad-leaved forest.The quantity of soil microbe reduced under Chinese fir plantation and added under broad-leaved forest.Oxidation-reduction enzyme activity of soil was stronger and hydrolase activity of soil was weaker under broad-leaved forest in contrast with those of soil under Chinese fir plantation,activities of two types of enzyme systems of soil tended to be weakened under Chinese fir plantation and be strengthened under broad-leaved forest in three years.The results revealed that soil fertility was deteriorated after planting Chinese fir and was promoted after recovering broad-leaved forest in three years.