摘要
在河西盐渍化土地区选择了天然草地、小麦地、1年生苜蓿地、2年生苜蓿地和3年生苜蓿地,就不同利用方式对盐渍化土有机质和盐分的影响进行了研究。结果表明,种植农作物后,土壤的有机质含量明显下降;种植苜蓿后,前2年土壤有机质含量减少,3年后显著增加。土壤盐分在开垦种植后显著下降,苜蓿地的降盐效果更好。可溶性阳离子中,Mg2+含量的下降趋势最大,其变化曲线与全盐相同;Na+向土壤下层迁移,Ca2+含量随土壤深度的增加而降低,K+含量下降。
Five types of land use patterns （native pasture, farmland, 1, 2, and 3 year-old Medicago sativa cutuvations）, were studied to investigate changes in soil organic matter concentration and soil salt. Soil organic matter decreased dramatically after cultivating crops and 1 or 2 year-old M. sativa, but increased after 3 year-old M. sativa. Soil salt decreased markably when native pasture was reclaimed, especially in M. sativa land. Concentrations of soluble cations were reduced through to greater soil depths. A significant decline of Mg^2＋ was observed and was significantly correlated with soil salt. Na＋ tended to move to greater soil depths. The concentration of Ca^2＋ decreased with depth of the soil layer and K^＋ decreased in the soil.
出处
《草业学报》
CSCD
2007年第4期15-20,共6页
Acta Prataculturae Sinica
关键词
盐渍化土
土地利用方式
有机质
盐分
saline soil
land use pattern
organic matter
salinity
