连续不同施氮对小麦-玉米轮作农田土壤理化性状的影响

Effect of Different Continuous Nitrogen Application on Soil Physicochemical Properties in Wheat-Maize Rotation System

为明确施氮量对农田土壤理化形状的影响,以小麦-玉米轮作体系为研究对象,通过4年连续定位试验,比较了连续不同施氮处理对不同土层土壤理化指标的影响。结果表明,连续不同施氮处理对土壤有机质和全氮含量、碳氮比、土壤容重有显著影响,但对pH的影响较小。在0~30cm土层,土壤有机质和全氮含量随施氮量的增加而增加,当施氮量为240kg·hm^(-2)时,有机质含量增加速率最快,当施氮量为360kg·hm^(-2)时,土壤全氮含量最高。在30~60cm和60~90cm土层,不同施氮处理对土壤有机质、全氮含量的影响降低。综合土壤碳氮比和容重等指标,本区域推荐施氮量为240kg·hm^(-2)。

To discuss the effect of nitrogen application rate on soil quality,a 4-year continuous positioning test was conducted in wheat-maize rotation system,comparing the changes of soil physical and chemical indices in different soil layers under the continuous nitrogen application.The results indicated that different continuous nitrogen application rate had significant effect on soil organic matter,total nitrogen,C/N ratio and soil bulk density,while it had little effect on soil pH.In 0-30 cm soil layer,soil organic matter and total nitrogen content was increased with the increasing of nitrogen application rate.When the nitrogen application rate reached 240 kg·hm^(-2),soil organic matter content increased the fastest,and when the nitrogen application rate was 360 kg·hm^(-2),soil total nitrogen content was the highest.In 30-60 cm and 60-90 cm soil layers,the effects of different nitrogen treatments on soil organic matter and total nitrogen content were decreased.According to soil nitrogen and carbon ratio and bulk density,nitrogen fertilizer in this region is recommended as 240 kg·hm^(-2).