摘要
采用二阶段抽样法,选取林木生长、多样性、土壤、地形等指标对渭北水土保持林进行调查和统计分析。结果显示:该地区水土保持林资源分布不均,整体上表现为西多东少,北多南少的分布格局;虽然防护林还没有进入更新期,但是已有大量近熟林在高生长和径生长上表现出明显的衰退迹象;树种结构的单一、灌木层的缺乏使得林分整体多样性不高,林下更新不足,严重地影响了森林的自我更新和复制;通过偏相关分析得出,郁闭度、密度、枯落物等因子的协作用对防护林土壤表层(40cm)持水能力的影响显著大于每个因子自身的作用。以上结果表明,该地区水土保持林在结构、生长和更新中存在着许多问题,必须通过合理的经营设计改变这一现状,以实现该地区水土保持林的可持续经营。
The two-stage sampling method was used,the indices of tree growth,diversity,soil relief and expansion index were set up following the ecological benefit assessment scheme and surveyed to study the situation of soil and conservation forest in Weibei region.The results show that the distribution of soil and water conservation forest in this region is imbalanced there are more forests in the west and north than the eastern and southern part of this region.The shelter forest has not yet entered a regeneration period,yet many near-mature forests have the decline appearance on the growth of tree DBH and height.Simple forest structure and shrub layer caused the lower forest diversity.The lack of regeneration blocks the renewable and duplicate of the forest.Moreover,the result of partial correlation shows that the crown density,number of tree,litter and so on have the synthetic action on the soil water holding capacity.All the results show that there are many problems（structure,growth and regeneration） in the soil and water conservation forest.In order to change this situation and realize the target of sustainability,a reasonable forest management design should be carried out.
出处
《水土保持研究》
CSCD
北大核心
2013年第3期257-262,共6页
Research of Soil and Water Conservation
基金
国家林业局公益性行业专项(201004002)
博士后科学基金(2012M510331)
关键词
水土保持林
水土流失
二阶段抽样
可持续经营
soil and water conservation forest
soil loss
two-stage sampling
sustainable management
