白龙江水源涵养林不同林龄土壤性状

[目的]调查研究甘肃南部白龙江水源涵养林的土壤水分物理性质及土壤养分含量，为白龙江上游水源涵养林生态修复、环境保护营造和抚育提供有益借鉴。[方法]以白龙江林区4种林龄人工油松林类型0～40cm土壤层为研究对象，探讨人工油松林恢复演替过程中土壤理化性质的变化规律。[结果]（1）不同林龄斑块之间土壤水分有显著的梯度变化，白龙江人工油松林土壤总孔隙度、毛管孔隙度、自然含水量、最大持水量、毛管持水量、田间持水量均随树龄的增加而增大；pH值差异不显著，无明显变化规律；土壤有机质、全氮、水解氮、有效磷、速效钾均随树龄的增加而变大；速效磷差异不显著；（2）随着树龄的增加，树龄大的土壤孔隙度、持水能力、渗透性明显好于树龄小的，随森林坡位的降低，坡下孔隙度明显高于坡上，通透性能不断增强，pH值在坡上坡下没有明显的差异；（3）有机质与全氮、碱解性氮、最大持水量、毛管持水量、田间持水量呈显著正相关；全氮与碱解性氮呈显著正相关；土壤有机质在改善土壤理化性质和促进养分循环方面具有重要作用，已成为植被涵养水源的一个重要标志。[结论]该研究为白龙江林区退化森林生态系统恢复和重建提供依据．

Soil Properties of Bailong Jiang Water Conservation Forest in Different Age

[ Objective ] Soil properties of Bailong Jiang water conservation were studied in order to provide reference for ecological restoration and environment protection. [ Method ] Taking Bailong Jiang Forest to four different types of artificial Chinese pine forest age 0-40 cm soil layer for the study, the soil properties of artificial pine forest restoration succession process variation were explored aimed at provide the basis for forest eco-system recovery and reconstruction. [ Result ] ①There are significant variations between different forest age gradient patches of soil moisture, the Bailong total artificial pine forest soil porosity, capillary porosity, natural moisture content, maximum water holding capacity, capillary water, field capacity were increased with increasing age rather large, pH value has no significant variation. Soil organic matter, total N, hydrolytic N, available P, available K were increased with increasing age becomes larger：Available P was not significant. ②With increasing age, the old large soil porosi-ty, water holding capacity, permeability was significantly better than the old small. With the decreasing of forest slope position, significantly higher than the porosity of the lower slope slope, permeability can continue to strengthen, pH has no significant difference in the value of the slope in the slope;③Organic matter has significant posifine correlation with total N, alkaline hydrolysis of N, the maximum water holding capacity, capillary water and field capacity. Total N and alkaline hydrolysis of N showed a significant positive correlation. Soil organic matter has an important role in improving soil properties and promote nutrient cycling aspects which has become an important symbol in water conservation vegetation. [ Conclu-sion ] The study provide the basis for forest ecosystem recovery and resconstruction.