以探寻合理的滴头埋深与流量为目的,开展浅埋式滴灌下土壤水分分布规律的试验研究。试验土箱净尺寸为30cm×30cm×60cm(长×宽×高),供试土壤取自新疆青河县阿苇灌区试验站。试验设置5、10、15 cm 3个滴头埋深,各埋深...以探寻合理的滴头埋深与流量为目的,开展浅埋式滴灌下土壤水分分布规律的试验研究。试验土箱净尺寸为30cm×30cm×60cm(长×宽×高),供试土壤取自新疆青河县阿苇灌区试验站。试验设置5、10、15 cm 3个滴头埋深,各埋深条件下设置不同流量的处理。结果表明:不同滴头埋深的情况下均存在土体破坏的临界流量,滴头埋深越大临界流量也越大,滴头埋深为5、10和15 cm对应的临界流量分别为1.0、1.7和2.5 L/h;随着流量的增大,滴头埋深过浅时,水量向湿润体上部聚集,当埋深超过一定深度时,水量向湿润体下部聚集;在临界流量情况下,湿润锋前60 min运移速率较快,随着滴头埋深的增大,灌水结束后湿润体的垂向湿润长度越长,土壤平均含水率值越小;滴头埋深为10 cm、流量1.7 L/h时,湿润体水分分布较为合理。展开更多
This study was carried out to explore the effects of leaching salinity under subsurface drainage and mulched drip irrigation on saline and alkaline land from the year 2012 to 2014 in Xinjiang Region of China.Three sam...This study was carried out to explore the effects of leaching salinity under subsurface drainage and mulched drip irrigation on saline and alkaline land from the year 2012 to 2014 in Xinjiang Region of China.Three sampled points were both set up in the subsurface drainage and ditch drainage areas.Soil samples were obtained at varied depths.Through observing the underground water table under each sampled point and measuring the electrical conductivity(EC)of the soil extracts,the following results were obtained:(1)after draining,the underground water table ranged from 1.6 m to 2.2 m in the ditch drainage area,and ranged from 1.5 m to 2.2 m in the subsurface drainage area.Thus,both irrigations could control underground water table below 1.5 m which is deeper than the main water-absorbing layers of crop root systems;(2)for subsurface drainage,the closer to the pipe,the better to leach salinity;decreased from the initial 13.54-22.95 g/kg to 8.20-11.47 g/kg;(3)compared with the amounts in 2012,soil total salt at each sampling point at depths of 0-200 cm in subsurface drainage area decreased by 42.99%,36.84%and 24.41%respectively in 2014;and in ditch drainage area decreased by 46.85%,38.12%and 30.80%respectively in 2014.The results showed both ditch and subsurface drainage could leach salinity effectively.展开更多
基金the National Natural Science Foundation of China(U1203280,U1403183,51269067,41361071,51669029)the National Key Research Project“13th Five-year”(2016YFC0501402,2016YFC0501406)the National Key Research Project“12th Five-year”(2015BAD20B03).
文摘This study was carried out to explore the effects of leaching salinity under subsurface drainage and mulched drip irrigation on saline and alkaline land from the year 2012 to 2014 in Xinjiang Region of China.Three sampled points were both set up in the subsurface drainage and ditch drainage areas.Soil samples were obtained at varied depths.Through observing the underground water table under each sampled point and measuring the electrical conductivity(EC)of the soil extracts,the following results were obtained:(1)after draining,the underground water table ranged from 1.6 m to 2.2 m in the ditch drainage area,and ranged from 1.5 m to 2.2 m in the subsurface drainage area.Thus,both irrigations could control underground water table below 1.5 m which is deeper than the main water-absorbing layers of crop root systems;(2)for subsurface drainage,the closer to the pipe,the better to leach salinity;decreased from the initial 13.54-22.95 g/kg to 8.20-11.47 g/kg;(3)compared with the amounts in 2012,soil total salt at each sampling point at depths of 0-200 cm in subsurface drainage area decreased by 42.99%,36.84%and 24.41%respectively in 2014;and in ditch drainage area decreased by 46.85%,38.12%and 30.80%respectively in 2014.The results showed both ditch and subsurface drainage could leach salinity effectively.
