朔州市华北落叶松防护林生长状况及天然更新情况调查

Investigation on the Growth Status and Natural Renewal of North China larch Shelterbelt in Shuozhou City

目的调查朔州市华北落叶松防护林生长状况、土壤肥力,分析华北落叶松的天然更新情况。方法以朔州市华北落叶松防护林为研究地点,所有林分均为天然更新,按照不同林龄,将华北落叶松分为10~20a(Z1)、20~30a(Z2)和30~40a(Z3)3组样地,每组样地(50 m×50 m),采用回归分析等方法,对华北落叶松不同林龄其幼苗更新生长状况、土壤理化性质和林分天然更新情况进行分析。结果:①幼苗生长状况:华北落叶松防护林不同林龄间其幼苗长势良好,苗高、地径等指标以Z2最佳,表现为Z2>Z1>Z3,组间比较有显著差异(P<0.05),其中Z2落叶松株数低于Z1和Z3(P<0.05),且其中Z3>Z1(P<0.05);②土壤肥力:3组pH值比较无差异(P>0.05),Z2土壤有机质、全氮、全磷和速效钾含量明显高于Z1>Z3(P<0.05);③天然更新状况:Z2落叶松幼苗天然更新状况明显优于Z1和Z3,说明林龄、密度和土壤肥力直接影响林下幼苗天然更新情况。结论华北落叶松防护林20~30 a林龄下,幼苗密度良好,土壤肥力较佳,林间天然更新动态良好。

ObjectiveTo investigate the growth and soil fertility of larch shelterbelt in Shuozhou,and analyze the natural renewal of larch.Methods In the study site,all stands were naturally updated.According to different forest ages,they were divided into 10~20a(Z1),20~30a(Z2)and 30~40a(Z3)in each group(50m 50m)to analyze the growth conditions of seedlings of different trees.Results;①Seedling growth:The seedlings grow well between different forest ages of Huabei larch shelterbelt,Miao height and ground diameter are the best by Z2,Presented as Z2>Z1>Z3,A significant difference between the groups(P<0.05),Specifically,Z2 larch strains were lower than Z1 and Z3(P<0.05),And in which Z3>Z1(P<0.05);②Soil fertility:there was no difference in pH values of 3 groups(P>0.05),The content of organic matter,total nitrogen,total phosphorus and quick-acting potassium in Z2 soil was significantly higher than that of Z1>Z3(P<0.05);③Natural renewal:the natural regeneration of Z2 larch seedlings is significantly better than Z1 and Z3,This indicates that forest age,density and soil fertility directly affect the natural regeneration of understory seedlings.Conclusion At 20~30a forest age,the seedling density is good,the soil fertility is good,and the natural renewal dynamics of the forest is good.