中国水土保持科学2017,Vol.15Issue(4):42-50,9.DOI:10.16843/j.sswc.2017.04.006
陕北黄土区阳坡阔叶混交林结构及点格局分析
Stand structure characteristics of broad-leaved mixed forest and point pattern analysis in loess sunny slope, northern Shaanxi
摘要
Abstract
[Background] Soil erosion is serious on the arid sunny slope in semiarid loess area.Soil moisture is the main limiting factor for the construction and restoration of forests and grass benefiting soil and water conservation.Only relying on natural enclosure is difficult to achieve ideal effects in the short term.Traditional artificial afforestation schemes ignore the heterogeneity of habitat conditions,which lead to poor afforestation survival rate,serious individual differentiation in the stand and weak overall stability.Thus,it is necessary to carry out studies on near-natural afforestation,investigating the structural characteristics and spatial distribution pattern of existing forest in the area,for providing scientific basic information concerning the construction of mixed forest of soil and water conservation.[Methods] In this research,a study slope (6.25 hm2) was selected from the western slope of loess area in Wucangpu Village,Wuqi County,northern Shaanxi.The spatial distribution,tree height and diameter at breast height (DBH) of "Armeniaca sibirica + Populus simonii + Robinia pseudoacacia" mixed forest were measured;the distribution characteristics of tree height and DBH were analyzed using Weibull function;and the point pattern analysis method was adopted to analyze the spatial distribution pattern of A.sibirica,P.simonii,R.pseudoacacia and the spatial correlation between the different populations.[Results] 1) A.sibirica and P.simonii were the main constructive species in the study area,while R.pseudoacacia was the companion species and A.sibirica took the advantage position in the community.2) The population of P.simonii featured trees in large and middle diameter class accounted for the majority;the population of A.sibirica featured trees in middle and small diameter class accounted for the majority;the population of R.pseudoacacia featured trees in small diameter class accounted for the majority.The stand overall growth was in medium status.The average height of P.simonii was significantly greater than that of A.sibirica and that of R.pseudoacacia,indicating that stratified structure of the stand was obvious.3) The A.sibirica,P.simonii and R.pseudoacacia featured aggregated distribution within the spatial scale of 0-125 m,which reached the highest aggregation intensity when the spatial scale came to 47,65 and 104 m,respectively.Trees were mainly distributed on the microtopography,and the maximum aggregation radius was consistent with the scale of microtopography.4) The A.sibirica,P.simonii and R.pseudoacacia presented a negative correlation within the spatial scale of 0-125 m and acute interspecific competition.[Conculsions] In order to increase the survival rate of afforestation,promote the quality of quick restoration of forests and grass for soil and water conservation,it is suggested that the mixed pattern and arrangement of seeds should be designed according to microtopography,and strengthen their management and tending.A.sibirica and P.simonii may grow on microtopography with fine water conditions,like the bottom of gully.R.pseudoacacia may grow on undisturbed slope.关键词
黄土区/阳坡/阔叶混交林/林分结构/点格局分析/微地形Key words
loess area/sunny slope/broad-leaved mixed forest/stand structure/point pattern analysis/microtopography分类
农业科技引用本文复制引用
张巍,朱清科,张婵婵,吴涛,刘崴..陕北黄土区阳坡阔叶混交林结构及点格局分析[J].中国水土保持科学,2017,15(4):42-50,9.基金项目
国家科技支撑计划课题“困难立地植被恢复技术研究与示范”(2015BAD07B02) (2015BAD07B02)