东北地区三种典型次生林土壤有机碳、总氮及微生物特征的比较研究

Soil Organic Carbon,Total Nitrogen and Microbial Properties under Three Secondary Forests in Northeast China

研究了东北东部山区暗棕壤和白浆土两种土壤类型上生长的三种典型次生林(白桦林、柞树林和杂木林)的林地土壤有机碳、总氮含量及土壤微生物特征,详细比较分析了相同土壤类型上的不同林分,以及不同土壤类型上分布的相同林分对不同层次土壤有机碳、总氮含量及微生物特征的影响差异.结果表明:A 层土壤中土壤有机碳、总氮含量及土壤微生物占绝对优势,且因土壤类型和林分的不同而有着显著差异.暗棕壤上各林分上土壤有机碳、总氮含量的顺序为:杂木林>白桦林>柞树林,且相互之间差异显著.杂木林的土壤微生物数量和生物量显著高于白桦林和柞树林,但是白桦林和柞树林之间的差异不显著;白浆土上土壤有机碳、总氮含量的顺序为:白桦林>杂木林>柞树林,土壤微生物数量和生物量的顺序为:白桦林>柞树林>杂木林,且相互之间差异显著.白桦林在白浆土上的有机碳、总氮及微生物数量和生物量显著高于暗棕壤,而杂木林在暗棕壤上的各检测指标均高于白浆土,柞树林在白浆土中的有机碳、总氮显著高于暗棕壤,但其微生物数量和生物量在两种土壤类型中的差异呈相反趋势.以上被检测的土壤有机碳、总氮及其土壤微生物数量和生物量等各指标间存在显著的相关性.

We compared soil organic carbon （SOC）, total nitrogen （TN） and microbial populations and biomass under Birch forests, Mongolian oak plantations and mixed plantations from Dark-brown earths and Albic soils in northeast China. The results showed that microbial populations and biomass decreased stepwise with the depth of soil associated with low organic content and low nitrogen status. There were significant differences amongst the tested soil characteristics from the different soil types and forests. In A layer Dark--brown earths, SOC and TN from mixed plantation, Birch forests and Mongolian oak plantations in turn decreased significantly. In addition, microbial populations and biomass from the mixed plantations was significantly higher than the other two forest types that there were not significant differences between them. In A layer Albic soils, abiotic characteristics from Birch forests, mixed plantation, Mongolian oak plantations in turn. However, biological characteristics decreased significantly from Birch forests, Mongolian oak plantations, mixed plantation in turn. There were also significant differences between the tested soil characteristics, both abiotic and biological characteristics, of the different forest types from the same soil type. The tested soil characteristics the mixed plantations in Dark-brown earths and the Birch forest in were significantly higher when compared the same forest type from the other soil types. The SOC, TN from the Mongolian oak plantations in Albic soils significantly higher the same one forest type from Dark-brown earths. However, the microbiological characteristics from Mongolian oak plantation in two soil types embodied the reverse trend. There were significantly positive relationships between the tested soil characteristics, both abiotic and biological.