微咸水灌溉对土壤盐分及冬小麦和夏玉米产量的影响  

Influence of brackish water on the soil salt regime and yield of winter wheat and summer maize

作　　者：毛振强[1] 宇振荣[1] 马永良[1] 

机构地区：[1]中国农业大学资源与环境学院

出　　处：《中国农业大学学报》2003年第z1期20-25,共6页Journal of China Agricultural University

基　　金：中荷合作资助项目 (SAIL SPP 2 99.399);国家重点基础研究发展规划资助项目 (G19990 1170 9)

摘　　要：1997— 2 0 0 1年间 ,研究了微咸水灌溉条件下 ,不同深度原位土壤溶液的电导率及其微咸水灌溉对冬小麦和夏玉米产量的影响。表明 :使用微咸水灌溉 ,0～ 80cm土壤溶液的电导率迅速升高 ,2年后较淡水灌溉处理同一深度土层土壤溶液的电导率高约 5～ 10mS·cm-1。在一个生长季节内 ,5 5 0mm的降雨和 2 5 0mm的灌溉水对盐分的最大淋洗深度一般都不超过 15 0cm。灌溉农田中 ,盐渍化最严重层是亚表层 (2 0～ 6 0cm)。当 2 0～ 6 0cm土壤溶液的电导率在 8mS·cm-1以下时 ,对夏玉米的产量无显著影响 ;若电导率长期维持在 10～ 15mS·cm-1之间且当季的降雨相对较少时 ,玉米产量将显著降低。当 2 0～ 6 0cm土壤溶液的电导率长期维持在 12～ 15mS·cm-1之间 ,在灌溉量较大的条件下 ,盐分胁迫所造成的冬小麦产量损失一般在 10 %左右。Drought and fresh water shortage are the main limited factors of sustainable agriculture development in the North China Plain (also referred to as the Huang Huai Hai Plain or 3-H Plain). The scarcity of fresh water forces farmers to use shallow saline ground water. The risk of soil salinity would increase. This paper describes the changes of soil salts and crop responses to brackish water irrigation based on field experiments from October 1997 to July 2001. It was found that brackish water irrigation resulted a rapid accumulation of salts, notably in the upper 80 cm soil layer. The maximal electrical conductivity (EC) of 20～40 cm soil layer exceeded 20 mS·cm -1. The salts were leached from 150 cm during the wet season. With the total precipitation of 550 mm and additional 250 mm irrigation water with high quality, all the salts in 80 cm soil layer of a sandy loam soil were leached. Irrigating with brackish water, the average yields of winter wheat and summer maize were 91% and 92% of the recorded maxima respectively, but only 67% and 89% if non-irrigation. Irrigation with the brackish water for three years, the yield of winter wheat was about 92% of the maximum. The experiments confirmed that brackish water irrigation was economically attractive to farmers for a short term. Ecological hazard may occur in long-term use of the water. The average electrical conductivity lower than 8 mS·cm -1 in the 20～60 cm soil had no significant effect on the yield of summer maize. The yield would significantly decline if the EC was 10～15 mS·cm -1 at dry year. However winter wheat yield would decrease by 10%.

关 键 词：微咸水 灌溉 电导率(EC) 

分 类 号：S274[农业科学—农业水土工程]