辽西地区覆膜条件对不同土层土壤氮磷钾累积量的影响

Effect of different mulching condition on total N,P and K content in different soil layers in semi-arid area of Liaoning province

为了探明覆膜技术对辽西半干旱区土壤氮磷钾累积量及其剖面分布状况的影响,本试验以农业部阜新农业环境与耕地保育科学观测实验站为研究平台,设置裸地种植、春季覆膜、秋季覆膜3种处理,通过对土壤剖面各层次全量氮、磷、钾的测定,定量分析辽西半干旱区覆膜条件下土壤全量养分含量及剖面分布差异,结果表明:不同覆膜处理对土壤全量氮、磷、钾累积量影响各不相同。2种覆膜处理可有效提高0～40 cm土层土壤全氮和全磷累积量,与裸地相比,春覆膜与秋覆膜处理可使土壤全氮提高34.4%和21.0%,秋覆膜处理可使全磷累积量提高17.0%。40～60 cm土层,裸地处理全氮、全磷累积量显著高于覆膜处理,其中全氮累积量较春覆膜处理提高65.7%,且为秋覆膜处理的2.16倍;全磷累积则表现为裸地种植比春覆膜和秋覆膜处理分别提高44.2%和39.4%。不同处理间全钾含量差异显著,总体表现为秋覆膜>春覆膜>裸地。3种处理土壤养分的剖面分布规律也各不相同,覆膜处理土壤全氮和全磷随剖面深度的增加呈逐渐减少的规律,而不覆膜处理则呈现先减少再增加的趋势;不同处理土壤全钾的剖面分布规律相似,即随剖面加深全钾含量均无显著变化,即使是表层土壤也未显示出全钾聚集的特征。

To clarify the soil nutrient content and distribution in semi-arid area of Liaoning province,a field study was conducted at Fuxin Science Observation Research Station of Agricultural Environment and Cultivated Land Conservation,including the treatments of non-mulched,film mulching in spring and film mulching in autumn.The total soil N,P and K contents in different soil layers were measured and analyzed.The results showed that mulching increased the content of total N and P in 0～40 cm soil layer.The total N was increased by 34.4%and 21.0%by mulching in the spring and autumn,respectively.The total P was increased by 17.0%by the treatment of mulching in the autumn.In 40～60 cm soil layer,the content of total N and P of non-mulched treatment was higher than that of mulching treatments.The total N accumulation was increased by 65.7%in contrast to the treatment of mulching in the spring,and 2.16 times higher than that of mulching in the autumn.The total P of non-mulching treatment was 44.2%and 39.4%higher than that of mulching in the spring and autumn,respectively.There were significant differences of total K among three treatments,which showed the order of mulching in autumn>mulching in spring>non-mulched.The soil profile nutrient distribution was different in three treatments.The total N and P in mulching treatments decreased as the soil layer getting deeper,while the non-mulched treatment decreased first and then increased.The distribution of total K in the three treatments were similar to each other,there was no significant variation among different layers in all treatments,even if on the top of the soil.