摘要
以恢复年限分别为14、36、50 a的落叶松人工林及相邻耕地表层土壤（0～10 cm）为研究对象,采用快速固结试验法,对土壤孔隙比、压缩指数、先期固结压力等指标进行测试,分析植被恢复对典型黑土表层土壤压缩性、承载能力的影响。结果表明：土壤孔隙比、压缩指数、先期固结压力,均随恢复年限的增加而增加,压缩指数、先期固结压力变化范围分别为0.231～0.399、4.2～100.0 k Pa。落叶松林地土壤压缩指数、先期固结压力,均显著高于耕地土壤（p〈0.05）;随植被恢复年限的增加,典型黑土表层土壤压缩性、承载能力逐渐提高,耕性有所增强。土壤力学性质指标与理化性质之间,表现出显著的相关性（p〈0.05）;压缩指数与土壤黏粒比例、有机质质量分数之间关系更为紧密（p〈0.01）;先期固结压力与土壤黏粒比例呈极显著负相关（p〈0.01）。植被恢复导致土壤有机质质量分数的增加;土壤密度和黏粒比例的降低,是黑土表层土壤压缩性增加、土壤承载能力增强的重要原因。
To explore the changes of black soil＇s compressibility and load support capacity in the restoration process,we took the topsoil（ 0-10 cm） in typical black soil region with vegetation restoration of 14,36 and 50 years and the nearby farmland as test objects. We used fast oedometer test to measure and calculate soil mechanical parameters,soil void ratio,the compression index and the pre-compression stress. The soil void ratio,compression index,and pre-compression stress were increased with the increasing year of vegetation restoration. The values of compression index and pre-compression stress were varied in 0.231-0.399,4.2-100.00 kP a,respectively. The compression index and pre-compression stress of soils at different age larch plantations were significantly higher than those of tillage soil（ p0.05）,that is,the compression index,pre-compression stress and the tilth of soil were increased with the increasing of recovery years. The soil bulk density,clay proportion decreased and the mass fraction of organic matter were increased with the increasing of recovery years,and good linear regressions were between bulk density,clay proportion,the contents of organic matter and soil mechanical properties. Bulk density had a negative influence on compression index（ p〈0.05）,the correlation between the contents of organic matter,clay proportion and compression index were closer（ p〈0.01）. Clay proportion also had a negative influence on precompression stress（ p〈0.01）. Therefore,degree of soil compaction decrease,soil compressibility and load support capacity were increased with the increasing of recovery years. The conceivable reasons for increasing the soil compressibility and load support capacity were the decrease of soil bulk density,clay proportion and the increase of the content of organic matter due to the vegetation recovery.
出处
《东北林业大学学报》
CAS
CSCD
北大核心
2016年第2期31-34,共4页
Journal of Northeast Forestry University
基金
国家林业公益性行业科研专项(201404202)
关键词
植被恢复
黑土
土壤
土壤压缩性
土壤承载能力
Vegetation recovery
Black soil
Soil
Soil compressibility
Soil load support capacity
