几种高分子材料固土性能比较与评价研究

Comparison and Evaluation of Soil Stability Affected by Macromolecule Materials

选用目前农业生产上应用较多的几种可用于地面成膜的高分子材料,模拟田间地表喷施处理,研究测试其在地表使用后对土壤结构有关的主要物理性质的影响。包括高分子材料对表土成膜性和抗破碎性的影响、对干湿土壤粒级分布变化的影响、对土壤团粒结构及土壤团粒水稳性的影响、以及对土壤水入渗性能的影响,分析比较高分子材料与固土有关性能关系。研究建议用SQ值(土壤水稳性结构商)、A%(>2mm团粒%)、WMWD(湿筛土壤平均重量粒径)可作为衡量干土团聚性能和湿土团聚水稳性能的主要指标,或作为对不同高分子固土材料的改土性能评价重要指标。用SQ值、A%、WMWD对不同高分子材料固土性能综合比较,MPAM(M-聚丙烯酰胺)处理的SQ值、WMWD值和A%值均为最大,表明其对表土成膜性、抗破碎性和团粒水稳性影响均最强,可优先推荐配合在节水灌溉和旱地保护性耕作土壤上应用;EBT(乳化沥青)处理的A%值排序最后,但SQ值和湿筛WMWD排序提前,表明其与土壤的固结力相对较强,可用于护坡固沙抗水蚀;CLP(交联性丙烯酰胺)处理的A%值排序靠前,但SQ值和湿筛WMWD排序最后,说明其与土壤的固结力和对土壤团粒水稳性影响相对较弱,适用于季节性干旱地区土壤保水保肥,尤其可作为经济作物的节水栽培管理措施。该研究为新型高分子材料的农用开发及其生产应用可行性提供依据。

Some macromolecule materials, widely used for soil surface conditioning in agricultural field at present, were selected to determine their effects of simulated surface application on soil aggregate-related physical properties, including on surface film-formation, soil erosion-resistance, changes in dry/wet particle-size distribution, soil aggregation and water-stability, as well as hydraulic conductivity, and to make comparison and evaluation of soil stability associated with the tested materials. The results suggested that the SQ （stability quotient）, A% （percentage of dry-sieved aggregates〉2 mm） and WMWD （wet-sieved mean-weight diameters） be used as main index to measure soil dry/wet aggregate stability or to evaluate soil stability of macromolecule materials. In comparison of the tested materials, the highest values in SQ, A% and WMWD associated with M-PAM （polyacrylamide） surface treatment showed that MPAM had the strongest effects on film-formation, erosion-resistance, and aggregate water-stability and can be recommended as practices combined with water-saving irrigation and soil conservation tillage in dryland soil. With EBT （emulsified bituminous material） treatment, the least A%, but the higher SQ and WMWD indicated that EBT had stronger aggregate water-stability and can be used on slope and sandy land for protecting soil against water erosion. With CLP （crosslinked polyacrylamide） treatment, the higher A%, but the lower SQ and WMWD suggested that CLP had the weaker wet aggregate water-stability and is suitable for water and fertilizer conservation in seasonal drought soils, and especially is applicable for water-saving cultivation management of cash crops. This study has provided informations for the development of new-type macromolecule materials in agricultural land application.