Sun Xiaohao, Miao Linchang, Wang Hengxing, Yin Wenhua, Wu Linyu
Institute of Geotechnical Engineering, Southeast University, Nanjing, Jiangsu, 210096, China.
China Design Group Co. LDT, Yinchuan, Ningxia, 210014, China.
J Environ Manage. 2021 Jun 1;287:112315. doi: 10.1016/j.jenvman.2021.112315. Epub 2021 Mar 10.
Sandstorms have been recognized as severe natural disasters worldwide and it is of great significance to propose an effective and environmentally friendly method to combat sandstorm. In this study, the enzymatic calcification (EC) treatment technology was used for mineralization crust and desert sand solidification. Both laboratory experiments and field site tests were conducted to demonstrate the feasibility of EC treatment to improve wind-erosion resistance and rainfall-erosion resistance. Results showed that with the concentration of reactants higher than 0.25 M or the ratio of urease solution to the cementation solution above 0.8, the improvement effects of wind-erosion resistance and rainfall-erosion resistance decreased. Therefore, the 0.25 M of reagent concentration and 0.8 of ratio of urease solution to the cementation solution were chosen for subsequent field site test. The two test sites had similar CaCO contents, thus obtaining a similar increasing range of surface strength. However, the test site one had larger surface strengths due to thicker cemented crust layers. Both the two test sites had sufficient wind-erosion resistance because of crust layer. Moreover, rainfalls decreased surface strength; the surface strength recovered to a high level after water evaporation. In addition, the effect of rainfall on thickness of crust layer and CaCO was small. The EC treatment had good ecological compatibility, and the combined EC and grass seed treatment was effective for mitigation of desertification. The results demonstrated that EC treatment significantly improved both wind-erosion and rainfall-erosion resistance, which presents promising potential for anti-desertification.
沙尘暴已被公认为全球范围内的严重自然灾害，提出一种有效且环保的防治沙尘暴方法具有重要意义。在本研究中，酶促钙化（EC）处理技术被用于矿化结皮和沙漠沙固化。进行了实验室实验和现场测试，以证明EC处理提高抗风蚀性和抗降雨侵蚀性的可行性。结果表明，当反应物浓度高于0.25 M或脲酶溶液与胶结溶液的比例高于0.8时，抗风蚀性和抗降雨侵蚀性的改善效果会降低。因此，选择0.25 M的试剂浓度和0.8的脲酶溶液与胶结溶液的比例进行后续现场测试。两个测试地点的碳酸钙含量相似，因此表面强度的增加范围相似。然而，测试地点一由于胶结结皮层较厚，表面强度较大。由于结皮层的存在，两个测试地点都具有足够的抗风蚀性。此外，降雨会降低表面强度；水分蒸发后表面强度恢复到较高水平。此外，降雨对结皮层厚度和碳酸钙的影响较小。EC处理具有良好的生态兼容性，EC与草籽联合处理对荒漠化治理有效。结果表明，EC处理显著提高了抗风蚀性和抗降雨侵蚀性，在防沙治沙方面具有广阔的应用前景。
