保护地黄瓜膜下滴灌及土壤中水分运行

Drip Irrigation under Mulch and Water Movement in Soil of Cucumber in Protected Field

2009年春季在河北省进行了保护地黄瓜滴灌试验和滴灌水分在土壤中运行的观察。结果表明:土壤绝对含水量(SAWC)与土壤水分张力(SMT)存在相关性。粘壤土SAWC(22.73%时,SMT=0.104 026×SAWC-2.866 41MPa,SAWC≥22.73%时SMT=3.527 1 lgSAWC-5.175 9MPa;粘土SAWC≤17.78%时SMT=0.108 329×SAWC-2.228 37MPa,SAWC(17.78%时SMT=1.530 3 lgSAWC-2.127 5MPa。据此计算,壤粘土温室越冬黄瓜的越冬期和初瓜期土壤水分张力应为-0.31^-0.25MPa,春季结果期为-0.13^-0.07MPa,但无论那个时期均不应高于-0.58MPa。保护地滴灌滴孔滴水速度以750 mL/h为宜,滴灌对土壤营养元素分布没有不同于漫灌的影响。

The drip irrigation under mulch and water movement in soil of cucumber in protected field was studied in Hebei Province in spring of 2009.The results showed that there was a correlation between the soil absolute water content（SAWC）and the soil moisture tension（SMT）.In clay loam,when SAWC was less than 22.73%,SMT =（0.104 026 × SAWC-2.866 41）MPa,and when SAWC was greater than or equal to 22.73%,SMT =（3.527 1 lg SAWC-5.175 9） MPa.In clay,when SAWC was less or equal to 17.78%,SMT =（0.108 329× SAWC-2.228 37） MPa and when SAWC was greater than 17.78, SMT = （ 1. 530 3 lgSAWC - 2. 127 5 ） MPa. Therefore,SMT should be - 0. 31 - - O. 25 MPa in clay loam during wintering and first fruiting stage and should be - 0. 13 - -0. 07 MPa at fruiting stage in spring, which should not be greater than -0. 58 MPa at any time. The suitable drip rate was 750 mL/h. The drip irrigation had no influence on the distribution of soil nutrient.