大兴安岭低质林改造后土壤肥力综合评价

Comprehensive Evaluation of Soil Fertility after Transformation of the Low-Quality Forest in the Daxing'anling Mountains

森林土壤是森林生态系统的重要组成部分,是林木赖以生存和健康生长的基础（周新年等,1998）。土壤肥力是土壤系统物理、化学和生物组分之间复杂且相互作用的综合体现,将影响并控制着林木的健康状态（Fisher et al.,2000）,它通常用土壤的物理、化学和生物指标等具有相互关联的特征来评价。因此,了解森林土壤肥力质量的特征变化,

This study studied the changes of soil physical and chemical properties and carbon flux of broadleaved mixed secondary growth stands and birch coppice low-quality forests after clearcutting with various bandwidths in the Daxing＇anling Mountains.Pinus sibirica,Pinus sylvestris var.mongolica and Larix gmelinii were planted after cutting.An improved AHP method was used for comprehensively evaluating the sites＇ fertility after the treatments.Results showed that the soil fertility quality index was higher than the control site for all treated sites except the broadleaved secondary P.sibirica stands in the 6 m cutting strip,where the soil fertility index was slightly less than the control site.In all the low-yield broadleaved secondary stand improvement treated sites,the soil fertility quality index of the site with the L.gmelinii stand planted in the 14 meter cutting strip showed the highest value of 0.744.In the sites after clearcutting birch coppice low-quality forests,P.sylvestris var.mongolica stands in the 14 meter cutting strip had the highest soil quality index of 0.617.According to the Spearman correlation analysis,major factors affecting soil fertility include soil organic matter,total nitrogen and hydrolysis phosphorus content.