氮磷分施和间作对春小麦花期土壤养分和酶活性的影响

Effects of Nitrogen and Phosphorus Separate Application and Intercropping on Soil Nutrients and Enzyme Activities at Flowering Stage of Spring Wheat

为了避免小麦生产过程中过量施肥对资源的浪费,明确春小麦适宜氮、磷肥用量以及种植方式,试验采用完全随机区组设计,分别设置0(N0)、90(N1)、180(N2)、270(N3)kg/hm^(2)共4个施氮水平,0(P0)、45(P1)、90(P2)kg/hm^(2)共3个磷肥水平以及春小麦间作豌豆(JC)、春小麦单作(DC)2种种植模式,研究氮、磷肥分施和间作对春小麦开花期土壤酶活性和土壤养分的影响。结果表明,不同施氮水平下,间作种植土壤脲酶活性、碱性磷酸酶活性、蛋白酶活性和有效磷含量均在N2水平下达到最大值,分别为5.32、16.27、1.68 mg/g和25.37 mg/kg,碱解氮含量在N3水平下达到最大值,为67.83 mg/kg,且土壤脲酶活性、碱性磷酸酶活性、有效磷含量在N2水平下,碱解氮含量在N3水平下均显著高于N0;不同施磷水平下,间作种植土壤脲酶活性、蛋白酶活性、碱解氮和有效磷含量均在P2水平下达到最大值,分别为5.17、1.83 mg/g和69.62、26.05 mg/kg,且在此施磷水平下土壤脲酶活性、碱解氮和有效磷含量均显著高于P0。种植模式×氮水平的交互作用极显著提高了土壤脲酶活性和土壤碱解氮含量,显著提高了土壤蛋白酶活性;种植模式×磷水平的交互作用极显著提高了土壤脲酶活性、过氧化氢酶活性和土壤碱解氮含量。说明施肥和间作种植对土壤酶活性和土壤养分含量的提高均有促进作用;在该试验范围内,间作模式下施氮量为N2(180 kg/hm^(2))、施磷量为P2(90 kg/hm^(2))时,效果最佳。

In order to avoid the waste of resources caused by excessive fertilization in the process of wheat production,and to determine the optimal application amount of nitrogen and phosphorus fertilizer and the optimal planting method for spring wheat,a completely random block design was adopted in this experiment.Four nitrogen application levels of 0 kg/ha(N0),90 kg/ha(N1),180 kg/ha(N2),and 270 kg/ha(N3),three phosphorus levels of 0 kg/ha(P0),45 kg/ha(P1),and 90 kg/ha(P2)were set,respectively,and two planting modes of spring wheat intercropping pea(JC)and spring wheat monoculture(DC)were used to study the effects of separate application of N and P fertilizer and intercropping on soil enzyme activities and soil nutrients at flowering stage of spring wheat.The results showed that under different nitrogen application levels,soil urease activity,alkaline phosphatase activity,protease activity,and available phosphorus content in intercropping soil reached the maximum values under N2,they were 5.32 mg/g,16.27 mg/g,1.68 mg/g,and 25.37 mg/kg,respectively,while the alkali-hydrolyzable nitrogen content reached the maximum values of 67.83 mg/kg under N3.Soil urease activity,alkaline phosphatase activity,and available phosphorus content under N2 and alkali-hydrolyzable nitrogen content under N3 were significantly higher than those under N0.Under different phosphorus application levels,soil urease activity,protease activity,alkali-hydrolyzable nitrogen,and available phosphorus contents reached the maximum values under P2,they were 5.17 mg/g,1.83 mg/g,69.62 mg/kg and 26.05 mg/kg,respectively.Soil urease activity,alkali-hydrolyzable nitrogen,and available phosphorus content were significantly higher than those under P0.The interaction of planting pattern×nitrogen level significantly increased soil urease activity and soil alkali-hydrolyzable nitrogen content,and significantly increased soil protease activity.The interaction of planting pattern×phosphorus level significantly increased soil urease activity,catalase activity,and soil alkali-hydrolyzed nitrogen content.The results showed that fertilization and intercropping promoted the improvement of soil enzyme activity and soil nutrient content.In the scope of this study,the effect was the best when nitrogen application rate was N2(180 kg/ha)and phosphorus application rate was P2(90 kg/ha)under intercropping mode.