盐碱棉田地表-地下接力式滴灌下水盐分布及棉花生长特征

地表-地下接力滴灌是集膜下滴灌和地下滴灌优点于一体的新型节水控盐技术，但目前针对该技术应用效果的研究尚少。针对如何对地表-地下接力式滴灌中的地表滴灌和地下滴灌进行水量分配效果最优这一问题，设置100%地表滴灌(W1)、75%地表滴灌+25%地下滴灌(W2)、50%地表滴灌+50%地下滴灌(W3)、25%地表滴灌+75%地下滴灌(W4)、100%地下滴灌(W5)共计5个处理，比较了不同水量分配下的地表-地下接力式滴灌与单一地表滴灌、单一地下滴灌对盐碱棉田土壤水盐分布和棉花产量的影响。结果表明：(1)W3处理根区土壤含水量分布最均匀，干燥区域面积最小。(2)W4处理窄行区域淋洗范围最大，脱盐效果最显著。(3)W3处理棉花吐絮期总干物质量和籽棉产量最大，分别为112.66 g和9 147 kg·hm^-2;吐絮期总干物质量比W1和W5处理分别提高11.3%和19.1%,籽棉产量比W1和W5处理分别提高14.1%和11.9%。地表-地下接力式滴灌处理下土壤含水量得以显著改善，在对土壤盐分进行淋洗的过程中表现出接力效应，淋洗面积和淋洗效果均有所增大。相比于单一地表滴灌和单一地...

Salt distribution and cotton growth characteristics of saline\|alkali cotton field under surface\|subsurface relay drip irrigation

Surface\|subsurface relay drip irrigation is a new water\|saving and salt\|controlling technology which combines the advantages of surface drip irrigation and subsurface drip irrigation, but there are still few researches on it. In response to the issue of how to optimize the water allocation effect of surface drip irrigation and subsurface drip irrigation in surface\|subsurface relay drip irrigation, five treatments were set up: 100% surface drip irrigation (W1), 75% surface drip irrigation+25% subsurface drip irrigation (W2), 50% surface drip irrigation+50% subsurface drip irrigation (W3), 25% surface drip irrigation+75% subsurface drip irrigation (W4), and 100% subsurface drip irrigation (W5). The effects of surface\|subsurface relay drip irrigation with single surface drip irrigation and single subsurface drip irrigation under different water allocation on soil water and salt distribution and cotton yield in saline alkali cotton fields were compared. The results showed that: (1) W3 treatment had the most uniform distribution of soil moisture content in the root zone, while the dry area was the smallest. (2) The narrow row area of W4 treatment had the largest washing range and the most significant desalination effect. (3) The total dry matter mass and seed cotton yield during the boll opening period of cotton under the W3 treatment reached the highest level, with 112.66 g and 9 147 kg·hm^-2, respectively. The total dry matter mass during the boll opening period increased by 11.3% and 19.1% compared with W1 and W5 treatments, respectively, and the seed cotton yield increased by 14.1% and 11.9% compared with W1 and W5 treatments, respectively. Under the surface\|subsurface relay drip irrigation treatment, the soil moisture content was significantly improved, and a relay effect was observed during the leaching of soil salt. The leaching area and effectiveness were both increased. Compared with single surface drip irrigation and single subsurface drip irrigation, the dry matter quality of cotton under surface\|subsurface relay drip irrigation significantly increased, and the yield significantly improved. The research showed that there was a good synergy between surface drip irrigation and subsurface drip irrigation. The 50% surface drip irrigation +50% subsurface drip irrigation was a better mode to regulate the water and salt distribution in saline alkali cotton fields, improve cotton yield and water use efficiency and provide theoretical support for the development of new water\|saving irrigation technology in alkali soil.