全膜双垄沟播改善干旱冷凉区盐渍土水盐状况提高玉米产量

为探明全膜双垄沟播技术在内陆干旱冷凉地区盐渍土的水盐调控机制,在山西省大同市,采用大田试验的方法,以半膜覆盖垄播(LB)、半膜平铺穴播(CK)为对照,研究全膜双垄沟播(QM)技术对盐渍土水盐时空动态变化及其对玉米生长发育的影响。结果表明:在苗期QM处理0~30 cm土壤含水率比LB和CK高3.6%和2.9%,在大喇叭口期比LB和CK高27.8%和7.0%,能大幅优化耕层土壤水盐环境,提高玉米的出苗率和成苗率;QM处理各层土壤含盐量均显著降低(P0.05),在大喇叭口期比LB和CK低28.3%、36.3%,在收获前期比LB和CK低31.2%、30.5%;对比1 m土体脱盐率,QM处理脱盐作用最强,比LB和CK高16.9%、30.7%,能大幅降低耕层土壤含盐量;QM处理比LB、CK玉米提早成熟4 d,增产69.7%和125.3%。总之,采用QM处理可以优化土壤耕层水盐分布,提高出苗率,缩短玉米生育进程,大幅提高产量。研究可为内陆干旱冷凉地区盐碱地的高效利用提供最佳的技术模式。

All-film double-furrow sowing improving water and salt conditions and increasing maize yield in saline soil of cold and arid area

Abstract: The saline land are 920.9 million hectares in China, and about 69.03% of it is distributed in the 6 western provinces belonging to the inland arid and cold area. Drought and wind in the early spring, and low soil temperature coupled with the harm of saline alkali often result in the low rate of maize emergence and weak growth of the seedlings. The study aimed to investigate the desalination effect of all-film double-furrow sowing in saline land in the arid and cold area. In 2012, 3 cultivation patterns were compared including all-film double-furrow sowing (QM), half-film mulch ridge sowing (LB) and half-film mulch hole sowing (CK). The spatio-temporal dynamics of temperature, soil moisture and salinity in the plowed soil during the growth of maize were analyzed and their effects on the rate of emergence, the process of growth and the yield of maize were assessed in Datong, Shanxi Province. The results showed that the soil temperature of QM and LB was increased significantly than CK in early growth stage. The warming effect of LB was highest in the seedling period and that of QM was in the jointing period. The water-salt environment in soil was optimized greatly in the QM treatment, and the emergence rate and the seedling rate of maize increased greatly. The soil moisture in the QM treatment at 0-30 cm was 3.6% and 2.9% higher than that in the LB and CK treatments under the drought conditions during the seedling stage, respectively, and 27.8% and 7.0% higher in the middle stage, respectively. The soil moisture of LB, QM and CK treatment in 1-m soil depth was 21.7%, 13.9% and 13.6%, respectively. The soil moisture of plow layer in the QM treatment was higher than that of CK, indicating that the QM treatment was good at water supply to plant. The soil salinity in the QM treatment reduced, which was 28.3% and 36.3% lower in the middle stage and 31.2% and 30.5% lower in the late stage than that of LB and CK, respectively. In the harvest season, the soil salinity of LB and CK was maximized in 30 cm depth but that of the QM was not accumulated in 30 cm. The emergence rate of the LB was highest, and the seedling rate of the QM was highest. In the big trumpet period, the plant height of QM was 20.3% and 27.1% higher and the dry weight was 49.6% and 57.3% than that of LB and CK, respectively. The maize in the QM treatment matured 4 days earlier than that in the CK and LB. The grain yield in the QM treatment increased by 69.7% and 125.3% compared to CK and LB, respectively. In short, the use of QM treatment could optimize the water-salt distribution in plowed soil, improve germination rate, shorten the growth period of maize, and considerably increase grain yield. All-film double-furrow sowing is a good cultivation pattern for saline land in inland cold arid area.