Fu Yuliang, Wang Shunsheng, Gao Shikai, Wang Songlin, Gao Zhikai, He Zhenjia
School of Water Conservancy, North China University of Water Resources and Hydropower, Zhengzhou 450045, China.
Shaanxi Provincial Land Engineering Construction Group Co., Ltd., Xi'an 710075, China.
Polymers (Basel). 2022 Sep 27;14(19):4056. doi: 10.3390/polym14194056.
In order to effectively suppress the negative effects of salt ions contained in saline soils on agricultural soil quality and crop growth, this study took advantage of the water-saving properties and better soil improvement properties of poly-γ-glutamic acid (γ-PGA). By carrying out various experiments, the following relationships have been found. (1) The lab experiment studies the effect of the γ-PGA application on the infiltration of sandy loam soil. The application rates of γ-PGA are 0%, 0.1%, 0.2%, and 0.3%, respectively. (2) HYDRUS-1D is used to simulate water infiltration of sandy loam soil under multiple factors (bulk density, γ-PGA application rate, and the application depth of γ-PGA). (3) The effect of γ-PGA on soil solute (Cl−) transport is also explored in this paper. The results show that bulk density and the application depth of γ-PGA (p < 0.01) have higher effects on cumulative infiltration than the application amount of γ-PGA (p < 0.05). A lower γ-PGA application rate will increase the proportion of unavailable soil water by 3%. The established empirical models have good results. Furthermore, when the γ-PGA application rate is 0.3% (0.02-cm2 min−1), the Cl− hydrodynamic dispersion coefficient is the highest. The study recommends applying the γ-PGA at 1.4 g cm−3, 5−20 cm, and 0.2%. The results of this study are conducive to an in-depth understanding of the physicochemical properties of poly-γ-glutamic acid, improving the utilization rate of salinized land, achieving agricultural water and fertilizer conservation and yield enhancement, and guaranteeing sustainable land use and sustainable development of agroecological environment.
为有效抑制盐碱土中所含盐分离子对农业土壤质量和作物生长的负面影响，本研究利用了聚γ-谷氨酸（γ-PGA）的节水特性和较好的土壤改良特性。通过开展各种实验，发现了以下关系。（1）实验室实验研究了γ-PGA施用量对砂壤土入渗的影响。γ-PGA的施用量分别为0%、0.1%、0.2%和0.3%。（2）利用HYDRUS-1D模拟多因素（容重、γ-PGA施用量和γ-PGA施用深度）作用下砂壤土的水分入渗。（3）本文还探讨了γ-PGA对土壤溶质（Cl−）运移的影响。结果表明，容重和γ-PGA施用深度（p<0.01）对累积入渗的影响比γ-PGA施用量（p<0.05）更大。较低的γ-PGA施用量会使无效土壤水分比例增加3%。所建立的经验模型效果良好。此外，当γ-PGA施用量为0.3%（0.02-cm2 min−1）时，Cl−水动力弥散系数最高。该研究建议以1.4 g cm−3、5−20 cm和0.2%的用量施用γ-PGA。本研究结果有助于深入了解聚γ-谷氨酸的理化性质，提高盐碱地利用率，实现农业节水节肥和增产，保障土地可持续利用和农业生态环境可持续发展。
