辽西北风沙半干旱区垄膜沟播处理对土壤氮、磷吸附/解吸特性的影响研究

Effect of Ridge Film Mulching and Furrow Seeding Technique on N and P Sorption-Desorption Characteristics of Soils in Semi-Arid Region of Northwestern Liaoning

为了探明不同垄膜沟播处理对土壤氮、磷养分吸附-解吸的影响,本研究以农业部阜新农业环境与耕地保育科学观测实验站为平台,通过定位7年(2007年~2013年)的田间试验,结合实验室内批量平衡法,以传统种植(T0/CK)为对照,对长期垄膜沟种(垄上覆膜沟内不覆盖(T1),垄上覆膜沟内覆膜(T2))条件下根际土壤对重要养分氮、磷的吸附/解吸能力进行研究和分析,结果表明:垄膜沟种处理有助于降低土壤对氮、磷养分的吸附,通过拟合Langmuir方程和Freundlich方程所求得的MBC和Kf值等相关参数可知,垄覆膜沟不覆盖种植处理土壤对氮、磷的吸附容量和吸附强度最小,最有利于削弱土壤对氮、磷的吸附作用,减少氮、磷固定,各处理对氮吸附的MBC值表现为:T1(6.70)<T2(7.41)<T0(8.05),对磷吸附的MBC值为:T1(10.48)<T2(13.18)<T0(16.55)。垄膜沟种处理土壤对氮和磷的解吸量也大于传统种植处理,不同垄膜沟种处理土壤对氮的解吸率为:T1(65.0%)>T2(62.3%)>T0(53.5%),平均滞后系数为:T0(0.46)>T2(0.37)>T1(0.34);对磷解吸能力表现为:T2(16.8%)>T1(14.6%)>T0(8.8%),平均滞后系数为T0(0.91)>T1(0.85)>T2(0.83),垄覆膜沟不覆膜(T1)处理最有利于氮的解吸,垄覆膜沟覆膜处理(T2)最有利于磷的解吸。垄膜沟种可通过降低土壤有机质含量、p H和阳离子交换量来减少氮、磷的吸附,增加氮、磷养分的解吸。

To clarify the N and P adsorption- desorption c haracteristics of soil in different treatments of ridge film mulching and furrow seeding technique, a field study was conducted for 7 years(from 2007 to 2013) at Fuxin Science Observation Research Stations of Agricultural Environment and Cultivated Land Conservation, including the treatments of ridge film mulching(furrow was uncovered, T1), ridge and furrow film mulching(T2), and the traditional planting(T0/CK), combine with the laboratory experiment to analyze the effects of different ridge film mulching and furrow seeding treatments on soil N and P adsorption- desorption. The results indicated that ridge film mulching and furrow seeding treatments restrained the N and P adsorption by soils according to the Langmuir and Freundlich equation parameters such as MBC and Kf over the conventional cultivation pattern. There was a general tendency that T1 treatment was more favorable to decrease the maximum buffer capacity and bonding strength of N sorption. And the MBC value for N adsorption were: T1(6.70) < T2(7.41) < T0(8.05), MBC value for P adsorption were: T1(10.48) < T2(13.18) < T0(16.55). The ridge film mulching and furrow seeding treatments also had a stronger ability of desorption than conventional planting, the N desorption ability of different treatments was T1(65.0%) > T2(62.3%) > T0( 53.5%),hysteresis coefficient was T0(0.46) > T2(0.37) > T1(0.34), and the P desorption ability of different treatments was T2(16.8%) > T1(14.6%) > T0(8.8%), hysteresis coefficient was T0(0.91) > T1(0.85) > T2(0.83). T1 was more favorable for N desorption, while T2 was more favorable for P desorption. The ridge film mulching and furrow seeding technique influence the N and P sorption- desorption ability by reducing the soil organic matter content, p H and cation exchange capacity.