套种不同牧草的果园土壤对铵的吸附特性研究

Study on the Ammonia Nitrogen Adsorption Properties of Orchard Soil Interplanted with Different Forages

以套种不同牧草的果园土壤为研究对象,通过室内等温吸附实验,分析比较了各个处理对氨态氮的吸附特性,并将结果用不同的数学模型拟合进行分析。结果表明:当土壤的氨浓度超过一临界值时,其对氨离子的吸附量会出现明显上升,而在此临界值以下则变化不明显;套种不同牧草可不同程度地提高土壤的铵吸附能力,具体表现为圆叶决明>百喜草>平托花生>宽叶雀稗>CK(自然生日本草);各处理土壤铵等温吸附与多项式拟合效果最佳,与Freundlich、Temkin方程拟合达显著水平,Langmuir方程的拟合结果较差。

The orchard soil interplanted with different forages was used in the indoor isothermal adsorption experiment, and the ammonia nitrogen adsorption properties of different trentments were analyzed and compared with mathematical models. It showed that the adsorption of ammonia ion in soil would be increased obviously when the ammonium concentration was over the critical value, while that would not change significantly when the ammonium concentration was lower than the critical value. Intercropped different forages could improve the ammonia nitrogen adsorption properties, contributing in the following order： Chamaecrista Rotundifolia〉Paspalum notatum Flugge〉Arachis pintoi〉Pspalum Wettsteinii〉CK. The isothermal adsorption of different trentments had the best simulating effect with the polynomial, the simulating effect with Freundilch and Temkin reached significant level, and the simulating effect with Langmuir was poor.