摘要
为探讨开垦对典型黑土表层土壤压缩与回弹行为的影响,以未经开垦天然次生林和开垦年限为17 a、30 a、40 a耕地的表层(0~10 cm)土壤为研究对象,采用快速固结试验方法,研究了土壤压缩与回弹过程中土壤孔隙比(e)、压缩指数(C_c)、压缩系数(a)和回弹指数(C_s)的变化。结果表明:土壤孔隙比(e)、压缩指数(C_c)、压缩系数(a)和回弹指数(C_s)随着开垦年限的增加而降低,C_c、a、C_s变化范围分别为0.252~0.426、0.002 04~0.003 70 k Pa^(-1)、0.041~0.070;未经开垦天然次生林地土壤C_c、C_s显著高于耕地土壤(p<0.05);C_c、a、C_s与容重均呈极显著负相关(p<0.01),与有机质含量呈极显著正相关(p<0.01)。土壤压缩性与回弹能力随着开垦年限的增加逐渐降低,容重、有机质含量对其影响最大。
In the black soil region of Northeast China,the issue of the soil getting more and more compact due to the extensive use of farming machines has been arousing more and more concerns among the people. Soil compaction has been considered one of the main causes of degradation of agricultural soils worldwide,because it reduces soil porosity and water infiltration,while enhancing soil intensity and soil consistence,which in turn impede root penetration into the soil and consequently reduce land productivity. Despite of this,little has been done on mechanical properties of compression and rebound of black soil typical of Northeast China. It is,therefore,essential to explore compression behavior of the soil for prediction of possible changes in soil structure under the pressure of farming machines. To explore effects of reclamation in mechanical properties of compression and rebound of the black soil,plots of black soil fields different in reclamation history,i.e. 17（Plot 17）,30（Plot 30）and 40（Plot 40）years and un-reclaimed natural secondary forest land（Plot 0）,were cited for soil sampling using a ring sampler,2.00 cm high and 6.12 cm in diameter and the soil samples were analyzed for soil void ratio,compression index,compression coefficient,and rebound index with a fast oedometer. Results show that soil void ratio,compression index,compression coefficient and rebound index all went down with the cultivation going on. During the compression process,Plot 0 was obviously higher than Plots 17,30 and 40 in soil void ratio（p〈0.05）;Plot 17 higher than Plots 30 and 40（p〈0.05）;and Plot 30 did not differ much from Plot 40. And during the rebound and recompression phase,the four plots displayed a variation pattern similar to that during the compression process. Compression index,compression coefficient and rebound index of the soil varied from 0.252 to 0.426,0.002 04 to 0.003 70 k Pa～（-1）,0.041 to 0.070,respectively. Plot 0 was significantly higher than the other three plots（p〈0.05）,and Plo
出处
《土壤学报》
CAS
CSCD
北大核心
2016年第3期646-653,共8页
Acta Pedologica Sinica
基金
国家自然科学基金项目(41271293
41302222)资助~~
关键词
开垦
黑土
孔隙比
压缩指数
回弹指数
Reclamation
Black soil
Void ratio
Compression index
Rebound index
