The Effect Of Agronomic Measures On Soil Nitrogen Forms And Nitrogen Pool Management Index In Bashang, Northern Hebei

Soil nitrogen form and nitrogen pool management index were important indicators for evaluating soil quality and soil management.In order to explore the suitable agronomic measures for developing eco-agriculture in Bashang area of northern Hebei province.The experiment was conducted to study the effects of different agronomic measures such as planting methods,organic fertilizer,water and fertilizer,mulching on soil nitrogen forms and nitrogen pool management index in Bashang.The contents of total nitrogen,soluble total nitrogen,ammonium nitrogen and nitrate nitrogen in sample soil were determined,and soluble organic nitrogen and soil nitrogen pool were considered.Management index and other indicators were used to analyze soil nitrogen forms and soil nitrogen pool management index under different agronomic measures.In this study we explored the most appropriate agronomic measures and optimized the suitable planting structure system under the development of ecological agriculture in Bashang.The results were as follows:1.Through the study of soil nitrogen form and nitrogen pool management index of Bashang in northern Hebei Province under different planting modes,it was found that soil TDN content ranged from 204.34 mg/kg to 489.17 mg/kg under different planting modes,and soil DON content ranged from130.74 mg/kg to 820.23 mg/kg in nitrogen form components,which accounted for the largest proportion of soil total nitrogen,while the proportion of DIN was the smallest;soil TDN,DON and DIN content under greenhouse vegetable planting mode was higher than that under greenhouse vegetable planting mode Grassland,oat land is the lowest;the nitrogen pool index under greenhouse vegetable cultivation mode is higher than grassland,and the nitrogen pool management index of ammonium nitrogen,nitrate nitrogen and soluble total nitrogen are also higher than grassland.Generally speaking,the TDN and DON contents of farmland soils in the high water and fertilizer management planting mode are higher than those in the extensive planting mode,which is not conducive to the utilization and accumulation of nitrogen in the farmland soils.In order to increase soil fertility and reduce soil wind erosion in Bashang area of northern Hebei Province,high fertility and water fine planting mode of greenhouse vegetables should be carried out.2.Through the study of soil nitrogen form and nitrogen pool management index of Bashang in northern Hebei Province with different organic fertilizer application rates,it was found that soil TN,TND and DON contents increased with the increase of organic fertilizer application rates;soil DON content increased significantly between 47.52 and 247.23 mg/kg,with 80%fertilizer application rate;the nitrogen pool index of 16t/hm2 fertilizer application rate treatment was 2.59 much higher than that of non-fertilizer treatment,and ammonium nitrogen and nitrate nitrogen were also higher than that of16t/hm2 fertilizer application rate treatment.Nitrogen pool management index of TDN and TDN were also higher than that of non-fertilization treatment.With the increase of organic fertilizer application,soil soluble nitrogen content and nitrogen pool index showed an upward trend.The results showed that the soil quality could be improved with the increase of organic fertilizer application rate,so the suitable organic fertilizer application rate in Bashang area of northern Hebei was 16 t/hm~2.3.Through the study of different fertilizer and water management on soil nitrogen form and management index of nitrogen pool on the Bashang in northern Hebei,it was found that with the increase of organic fertilizer application rate and soil water content,soil TN,TDN,DON and DIN content showed an upward trend;under the condition of carbon-water coupling,the nitrogen form content of high-carbon and high-water treatment soil was the highest,while that of low-carbon and low-water treatment was the lowest.With the extension of incubation time,the contents of TDN and DON in soil increased first and then decreased,while the contents of ammonium nitrogen and nitrate nitrogen in soil decreased first,then increased and then increased.The results showed that the amount of organic fertilizer and water content were two important factors affecting soil nitrogen form and nitrogen pool.The amount of organic fertilizer mainly affected the content of TN and TDN in soil.The coupling effect of carbon and water affected the transformation of nitrogen forms in soil,which was conducive to plant absorption and utilization,and improved soil quality and cultivated soil fertility.4.Through the study of the effect of plastic film mulching on soil nitrogen form and nitrogen pool management index,it is concluded that the contents of TN,TND,DON and DIN in the soil between 60cm:50 cm plastic mulching is the highest,which is obviously higher than that of other plastic mulching methods;the nitrogen pool index of the soil between 60 cm plastic film mulching width plants is 1.69higher than that of other treatments,and the nitrogen pool management index of ammonium nitrogen and TDN is also higher than that of other treatments.Reasonably,the width of 60 cm:50 cm film mulching was most beneficial to the increase of soil ammonium nitrogen,soluble nitrogen and nitrogen pool index.The results showed that film mulching could affect the transformation of soil nitrogen form and increase soil nitrogen pool,especially after rainfall.The best film mulching method in Dryland was about 60 cm:50 cm.