摘要
经多年田间试验观察,分析渭北旱原裸地和农田土壤水分变化特征,根据土壤水分的年动态,可分为四个不同时期:即相对稳定期、缓慢消耗期、大量损耗期和恢复期。结合不同降水年型和不同作物,茬口及肥力分析其对土壤水分的影响,可以看出不同水文年土壤水分动态有较大差异,其中丰水年和干旱年土壤水分较平水年变化平缓。但土壤水分恢复程度不受作物(一年生),茬口和肥力的影响。根据垂直剖面土壤水分变化特点,依次将其分为三个层次:即活跃层、次活跃层和相对稳定层。丰水年活跃层仅为10cm,且10cm以下均为相对稳定层,干旱年活动层和平水年一致,但次活跃层仅为10cm。从整体情况看,平水年土壤水分变化均较干旱年和丰水年活跃。
This paper based on the perennial field experiment analysed the variations of soilwater behaviours in the bare land and farmland on the Weibei Rainfed Highland. Ac-cording to the annual behavior of soil water we can divide it into four stages: relative sta-bilization, slow loss of soil water, enormous loss of soil water and restoration. It can beseen in combination of the analysis of the effect of different types of rainfall years anddifferent crops, previous crops and soil fertility upon soil water that there is a great varia-hon in soil water dynamics in different hydrological years, of which soil water variesmore slowly in the rainy years and the dry years than in the normal years, but soil waterrecovery is not affected by crops (annual crops), previous crops and soil fertility. Basedon the varying behaviors of soil water in the vertical soil profile, three layers can be classi-fied, i.e. active, sub-active and relatively stable layers. In the rainy years, the active layeris only 10 cm deep under which there is the relatively stable layer. In the dry years, the ac-tive layer is the same as that in the normal years, but the sub-active layer is only 10 cmdeep. Viewed as a whole, soil water varise more greatly in the normal years than in thedry years and in the rainy years.
出处
《干旱地区农业研究》
CSCD
北大核心
1990年第4期27-36,共10页
Agricultural Research in the Arid Areas
关键词
土壤水分
旱地
农田水量平衡
Hydrological year
Soil water reserves
Feild water balance
Dry land
