摘要
【目的】通过研究华北典型井渠结合灌区不同用水模式对区域土壤盐分分布、根层土壤脱盐、地下水化学特征的影响,探讨华北井渠结合灌区适宜的渠井用水比例。【方法】2013—2015年在人民胜利渠灌区选择西三干渠控制范围为典型区域,监测控制范围内降水量、地表水灌溉量、地下水灌溉量、0—100 cm土层土壤含盐量、地下水矿化度,分析不同用水模式对根层土壤盐分洗脱、地下水化学特征的影响。【结果】2013—2015年一支渠、二支渠、三支渠渠井用水比例分别介于0.72—1.03、2.50—2.63、0.65—1.26之间;2013—2015年冬小麦苗期,不同用水模式下0—100 cm土层土壤盐分垂向分布均表现为上高、中低、下高,尤其是0—20 cm土层土壤盐分表聚明显;2013—2015年冬小麦苗期一支渠控制范围内0—20 cm根层土壤盐分均值大于0.32 mS·cm^(-1)面积分别占到控制范围的60.38%、25.99%、41.16%,二支渠控制范围内0—20 cm根层土壤盐分均值大于0.32 mS·cm^(-1)面积分别占到控制范围的59.61%、0.94%、8.81%,三支渠控制范围内0—20 cm根层土壤盐分均值大于0.32 m S·cm^(-1)面积分别占到控制范围的84.40%、41.87%、52.49%,表明渠井用水比例与支渠控制范围内表层土壤含盐量大于0.32mS·cm^(-1)的面积呈负相关;对比2013年同期,2014年典型区内0—20 cm土壤脱盐率介于15.61%—25.85%,2015年典型区内0—20 cm土壤脱盐率介于13.33%—23.15%;不同渠井用水比例典型区域地下水水化学特征均表现为:地下水中阳离子由枯水期钙钠型转化为平水期的钠钙型,平水期地下水水文化学相具有强烈的碱化趋势,特别是平水期二支渠地下水溶解性总固体增幅分别为一支渠、三支渠的1.23、3.48倍,表明较大渠井用水比例地表水灌溉驱动了根层土壤脱盐,增加了地下水中可溶性盐分浓度;对比2014年平水期,2015年同期一支渠、二支渠和三支渠控制范�
[Objective] The effects of water utilization patterns on root soil desalination and groundwater hydrochemical characteristics were studied in well-canal combined irrigation areas in North China. [Method] A representative area was selected in the Rennain Shengli Canal District from 2013 to 2015. Precipitation of the area, surface irrigation amount, groundwater irrigation amount, canal well water ratio （ratio of surface to groundwater irrigation amount, CWWR）, salinity in 0-100 cm soil layer and groundwater total dissolved solids were analyzed for different irrigation patterns. [ Result ] CWWR of 1 st, 2nd, 3ra branch canals was between 0.72 and 1.03, 2.50 and 2.63, 0.65 and 1.26 in 2013 to 2015, respectively. Soil saline contents of 0-100 cm layer under water utilization patterns were high in topsoil and lower layers, but low in middle layers. Salt accumulation occurred especially in the 0-20 cm soil layer. The ratio of the area with soil salinity greater than 0.32 mS.cm-1 to 1st branch canal irrigation areas was 60.38%, 25.99% and 41.16% in 2013 to 2015, for 2nd branch canal, was 59.61%, 0.94% and 8.81%, for 3rd branch canal, was 84.40%, 41.87% and 52.49%, respectively. The area with topsoil salinity greater than 0.32 mS.cm＇lof branch canals irrigated area was negatively correlated with CWWR, that is to say, the larger CWWR, the less areas with topsoil salinity greater than 0.32 mS＇cm-l of irrigation areas. Salt accumulation in topsoil was suppressed under the water utilization pattern of larger CWWR. Compared with 2013, desalination rate in 0-20 cm layer was between 15.61% and 25.85% in 2014, and between 13.33% and 23.15% in 2015. According to the desalination rate in 0-100 cm layer from 2013 to 2015, it was found that the desalination rate of root layers was improved under larger CWWR. Hydrochemical characteristics of groundwater was obvious alkaline because cation changed from Ca2＋/Na~ type in dry period to Na＋/Ca2＋ type in normal period, Specifically increase of total soluble solid of 2nd branc
出处
《中国农业科学》
CAS
CSCD
北大核心
2017年第3期526-536,共11页
Scientia Agricultura Sinica
基金
国家公益性行业(农业)科研专项(201203077)
中国农业科学院科技创新工程项目(CAAS-ASTIP-FIRI-03)
关键词
渠井用水比例
土壤含盐量
脱盐率
水化学特征
钠吸附比
井渠结合灌区
canal well water ratio
soil salinity
desalinization rate
hydrochemical characteristics
sodium adsorption ratio
well-canal combined irrigation district
