摘要
在长期定位试验的基础上，通过田间实地测定0-400cm土壤含水量，分析和比较了不同种植方式下苜蓿草地土壤水分的变化。结果表明，连作苜蓿地、轮作苜蓿地的400cm土层平均土壤含水量分别为10．6％和11．4％，均低于土壤稳定湿度，其干燥化指数为24．6％和37．2％，分别属强烈干燥化和严重干燥化，而小麦连作的干燥化指数为86．4％，属轻度干燥化。连作苜蓿地土壤干层最厚，400cm处仍十分干燥，而轮作苜蓿地和连作小麦地到240cm以下时，土壤水分开始有所恢复。连作苜蓿地和轮作苜蓿地通过降雨可恢复部分土壤水分，可恢复的土壤深度为40cm和60cm，而连作小麦地可达100cm。不同施肥措施下连作苜蓿地土壤干燥化程度都很严重，施肥措施不是造成土壤干燥化的主要原因。轮作系统中不同轮作年限苜蓿地的土壤水分状况有一定的差异，但是均没有形成深厚的土壤干层。与连作苜蓿相比，轮作苜蓿不会大量消耗土壤深层水分而形成深厚的土壤干层，有利于土壤水分的可持续利用。
Based on the long-term experiment started in 1984, soil water contents in 0-400 cm soil layers of alfalfa grasslands under different planting patterns were measured and the soil water variation was analyzed and compared. The results showed that average soil water content in 0-400 cm soil layers of the continuous cropping alfalfa field and alfalfa rotation field were 10.6% and 11.4% respectively, which were obviously lower than soil stable moisture. Their soil desiccation indexes were 24. 6% and 37.2%, which belonged to strong desiccation and serious desiccation respectively. But soil desiccation index of continuous cropping wheat field was 86.4%, which belonged to mild desiccation. The most thick soil dried layer was found in continuous cropping alfalfa field, which reached 400cm. However, the soil water began to be recovered under 240cm layers in continuous cropping alfalfa field and alfalfa rotation fi falfa field and alfalfa cm in continuous cro eld. Soil water could be partly recovered by the rainfall in continuous cropping alrotation field, and the depths were 40cm and 60cm respectively, but it was 100 pping wheat field. Soil desiccation intensities of continuous cropping alfalfa field under different fertilizer applications were all serious, so fertilizer application was not the main cause of soil desiccation. Soil water of different growth age alfalfa grasslands was a little different in alfalfa-grain crop rotation systems, but the deep desiccated soil layers were all not formed. Compared with continuous cropping alfalfa , alfalfa rotation would not consume dramatically water of deep soil layers, and then formed the dried soil layers, so it was benificial to the sustainable consumption of soil water.
出处
《西北农业学报》
CAS
CSCD
北大核心
2009年第3期141-146,共6页
Acta Agriculturae Boreali-occidentalis Sinica
基金
中国科学院知识创新工程重要方向项目KSCX1-YW-424-3和KSCX1-YW-N15-04
"十一五"国家科技支撑计划项目2006BAD05B07和2006BAD09B04
关键词
黄土高原
不同种植方式
苜蓿草地
土壤水分
Loess plateau
Different planting patterns
Alfalfa grassland
Soil water
