砒砂岩区生态恢复的新途径——一种环境友好型抗蚀促生技术

目的]对砒砂岩侵蚀岩性机理、抗蚀促生机理与技术,以及应用效果进行系统分析,并提出需要进一步研究的科学问题与关键技术,为砒砂岩区生态综合治理提供科技支撑。方法]通过揭示砒砂岩侵蚀岩性机理,利用聚合改性方法,研发了用于砒砂岩区生态恢复的抗蚀促生新材料,进行了示范应用,并对需要进一步研究的科学问题与关键技术进行讨论。结果]砒砂岩部分化学成分性质活跃、岩石结构不稳定及部分岩石成分遇水膨胀导致孔隙关闭为易蚀的机理所在;通过包裹—聚合改性,研发的抗蚀促生材料可以在砒砂岩表面通过物理化学作用,形成了具有包裹层的单体改性颗粒,起到了疏水保水及防胀作用,并具有促进植物生长的功能;抗蚀促生材料有着良好的力学性能和耐紫外线降解、耐风蚀抗冻融、耐水解等性能,且对土壤、水质不会形成污染。结论]根据野外试验观测,应用抗蚀促生技术可以使全坡面径流试验区的产流量产沙量分别减少70%和90%以上,示范小流域的植被覆盖度由25%提高到75%以上,实现了抗蚀促生功能一体化,为砒砂岩区水土流失治理和生态恢复提供了新途径。

A New Approach to Ecological Restoration in Pisha Sandstone Area-An Environment-friendly Technique of Anti-erosion and Vegetation-promoting

Objective] The lithologic mechanism of Pisha sandstone erosion, and the mechanism and technique of anti-erosion and vegetation-promoting, and the corresponding application effects were analyzed systematically. The scientific problems and key technique needed further research were proposed to provide support for the comprehensive control of Pisha sandstone area.Methods] On the basis of revealing the lithologic mechanism of Pisha sandstone erosion, a novel material of anti-erosion and vegetation-promoting, which is suitable for the application in ecological restoration in Pisha sandstone, was developed by the method of polymerization modification. The novel material was applied in a demonstration. Moreover, the problems and key techniques that needed to be studied further were proposed and discussed.Results] Some of the chemical compositions were detected active and released when Pisha sandstone met water, which was the main reason for Pisha sandstone being eroded easily. A novel material of anti-erosion and vegetation-promoting was developed by the method of coating-polymerization modification. The novel material could form a consolidation layer on the surface with monomer-modified Pisha sandstone particles through physical-chemical action. The layer had the functions of hydrophobic water-holding, anti-swelling and growth promotion. The novel material behaved well in the performances of mechanical strength and resistances to UV degradation, freezing and thawing, and hydrolysis, and it would not cause pollution to the soil and water wherein.Conclusion] Runoff and sediment yield on the slope could be reduced 70% and 90% respectively in the control area where was treated by the technique of anti-erosion and vegetation-promoting, as compared with those of the contrast area. And the vegetation coverage in a small demonstrated watershed increased from 25% to 75%, through which, the integration of anti-erodibility and growth promotion was achieved. The technique might provide a new approach for soil and water conservation and ecological restoration in Pisha sandstone area.