摘要
以湖南省大围山自然保护区花岗岩风化物发育的土壤为研究对象,选取天然林以及由此转化而来的人工林、果园和坡耕地4种土地利用方式,采用干、湿筛法测定了0~100 cm不同深度土层的土壤团聚体含量,计算表征团聚体稳定性的平均重量直径、几何平均直径、水稳性团聚体含量、分形维数和团聚体分散度等指标,分析土地利用变化对团聚体稳定性的影响。结果表明:土层深度及土地利用方式对土壤团聚体的组成及稳定性有显著影响;随着土层深度的增加,不同利用方式的土地土壤团聚体粒径组成及稳定性指标的差异逐渐增大;天然林和人工林的团聚体粒径较大,以>5 mm和2~5 mm为主,而坡耕地和果园的团聚体粒径以0.25~0.5 mm和0~0.25 mm为主;整体上,天然林和人工林的土壤团聚体稳定性较强,果园次之,坡耕地的团聚体稳定性较弱。该结果可为南方花岗岩红壤区土地利用优化和水土流失治理提供科学依据。
Taking the red soil developed from granite weathering material in Daweishan Nature Reserve of Hunan Province as the research object,four land use types including natural forest,artificial forest,sloping field and orchard were selected.The soil aggregate contents at 0-100 cm depths were determined by the dry and wet sieving method.The soil aggregate stability indices such as mean weight diameter(MWD),geometric mean diameter(GMD),the content of water stable aggregates(WSA),fractal dimension(D),and percentage of aggregate destruction(PAD)were calculated to investigate the effect of land use changes on the stability of red soil aggregates.Results show that land use pattern and soil depth can significantly affect the composition and stability of soil aggregates in the southern red soil region.Along with the increase of soil depth,differences in particle size composition and stability indicators of soil aggregates in different land use types gradually increase.The particle sizes of soil aggregates of natural and artificial forests are large,mainly in the range of 2–5 mm and>5 mm,while sloping fields and orchards mainly consist of 0.25–0.5 mm and 0-0.25 mm soil aggregates.Generally,the stabilities of soil aggregates of natural and artificial forests are relatively strong,followed by orchards,sloping fields are weak.The results of this study are helpful to optimizing land use types and improving soil and water conservations measures.
作者
崔家馨
李元辰
朱锟恒
段良霞
CUI Jia-xin;LI Yuan-chen;ZHU Kun-heng;DUAN Liang-xia(College of Resources and Environment,Hunan Agricultural University,Changsha 410128,PRC)
出处
《湖南农业科学》
2021年第1期35-39,49,共6页
Hunan Agricultural Sciences
基金
国家自然科学基金(41807076)
湖南自然科学基金(2019JJ50251)
湖南省大学生创新训练项目(S201910537061)。
关键词
花岗岩
红壤
团聚体
湿筛法
土地利用
granite
red soil
aggregate
wet sieving method
land use
