陕西黄土区近30a典型(土娄)土剖面肥力演变研究

利用典型剖面历史分析资料,采用原位采样及与历史资料相同的分析方法研究了陕西黄土区近30 a来蝼土肥力的演变及剖面养分分布.结果表明,与1982年第二次土壤普查资料相比,2008年蝼土耕层、犁底层中养分含量(除全钾)均有增加,耕层增幅最大,有机质增加了104.6%,全氮增加了61.7%,全磷增加了21.6%,碱解氮增加了67.3%,速效磷增加了255%;全钾含量在整个剖面都有不同程度的降低,耕层降幅最小,为9.6%.2008年各养分的表聚系数大于1982年,说明近30 a来蝼土土壤肥力不断提高,正向着有利于作物生长吸收的方向演变.

Changes of Fertility in Typical Lou Soil Profiles During Recent 30 Years in the Loess Area of Shaanxi Province

The study bosed on historical date of typical Lou soil profile in different years. In order to know the historical evolution and characteristics of nutrient on soil profile , the change of fertility and profile distribution of typical Lou soil in recent 30 years was studied by sampling . Results showed that the soil nutrient contents increased significantly in different soil layers ( except for total potassium) since the 1980s. Organic matter increased by 104. 6%; total nitrogen , by 61. 7%; total phosphorus, by 21. 6%; available nitrogen ,by 67 . 3 %; and available phosphorus, by 255 percent .Total potassium in the whole profile decreased to some extent , but in the top-soil , it declined only by 9. 6 %. In top-soil , the ration of soil nutrient content were greater in 2008 than those in 1982 . Long-term fertilization is helpful to enhance soil fertility and the fertility of Lou soil is propitious to growth and absorption for plants .