Study On Nutrient Management Under Rice-Mustard Rotation Cultivation Model In Fuling Region Discipline:Resource Utilization And Plant Protection

Fuling is located in the hinterland of the Three Gorges Reservoir area.The contradiction between the demand of arable land and area of arable land is prominent in this area.The agriculture is developed,the cropland replanting index is high,the farmland and agricultural activities are frequent,the slope farmland area is large,and the rainfall intensity is large.Many studies have shown that the agricultural non-point source pollution caused by farmers engaged in agricultural production in the Three Gorges Reservoir Area is mainly manifested in the excessive use of chemical fertilizers,the unreasonable proportion of fertilizers and the large amount of chemical fertilizer losses.?Zhang Weili 2004,Chen Yucheng 2008?.Mustard is one of the main economic agricultural products in Chongqing,and it is also the characteristic agriculture and agricultural economic pillar of Fuling.In recent years,due to the vigorous development of the rural economy,mustard cultivation has formed an important agricultural economic strategy in Fuling.Rice-mustard rotation is a typical mustard planting model in Fuling area,it is of great significance to study the nutrient management of the rotation system,improve the fertilizer utilization rate,reduce the loss of nitrogen and phosphorus,and prevent and control the pollution of water-based fertilizers in the Three Gorges Reservoir area.Through survey,understand and analyze the planting mode and fertilization status under the Rice-Mustard Rotation System in Fuling area,and provide basic data for the optimal management of nutrients in the rice-mustard rotation in this area.According to the survey results of 138 households:58%excessive nitrogen fertilizer and 43%excessive phosphorus fertilizer in the mustard season;And the excessive application of nitrogen and phosphorus fertilizers generally exists between the various production levels.?2?Most farmers in the rice season do not apply fertilizers,and only 20%of the farmers apply a small amount of fertilizers.The average nitrogen,phosphorus,and potassium fertilization for farmers is 6.73 kg/mu?N?,1.05 kg/mu?P₂O₅?,0.79kg/mu?K₂O?.?3?The planting mode of Rice-Mustard Rotation in Fuling area is:mustards are transplanted and planted around the autumnal equinox every year,and nutrient management is the application of chemical fertilizers,all the leaves of the mustard are returned to the field after the mustard harvest.Rice is transplanted about50 days after the mustard harvest,no fertilization during the entire growth period of rice.According to the survey results,the farmers'customary fertilization in the mustard season was optimized to the recommended fertilization,and phosphorus reduction treatment was set up on the basis of the recommended fertilization,to explore the effect of each fertilization treatment on the yield of mustard.What is the effect of fertilization on mustard leaves in the rice season?compared to chemical fertilizers??And how much is the amount of mustard leaves returned to the field?On the premise of guaranteeing the economic benefits of crops,find out the best fertilization method with environmental benefits.The research results are as follows:1.There is no difference between the stem yield and leaf yield of the farmer's customary fertilization and the recommended fertilization.The ratio of the stem and leaf yield of the recommended fertilization is greater.It can be seen that the farmer's customary fertilization increases the fertilizer input and does not increase the yield.The recommended fertilization is more conducive to the economic growth of mustard.There is no significant difference in yield between the recommended fertilization,the recommended fertilization and phosphorus reduction by 10%and phosphorus reduction by 20%.Phosphorus reduction of 10%and 20%will not result in reduced yield of mustard,and phosphorus reduction of 10%and 20%improves the phosphorus productivity and agronomy Utilization efficiency,a 10%reduction in the yield of stems,20%reduction in phosphorus,and 10%reduction in fertilization recommended are more beneficial to the economic production of mustard.Compared with the single application of chemical fertilizers,the two phosphate fertilizer control measures?combined with organic fertilizer and NaH₂PO₄?have better yield benefits than the combined application of NaH₂PO₄.By comparing the yields of mustard stems and leaves and the utilization efficiency of phosphate fertilizer,the benefits of superphosphate and monoamine phosphate were compared,and the benefit of monophosphate phosphate fertilizer was better.2.From the perspective of yield components,straw yield and grain yield,the yield benefit of 1 times the amount of Mustard leaves returned to field in all fertilization treatments is the best;the yield benefit of chemical fertilizer treatment is worse than that of each mustard leaves returned,and the recommended fertilizer treatment has significant Production cuts.1 times the amout of Mustard leaves returned is the best return amount,and then increasing the return amount will lead to a reduction in yield.It is recommended fertilization that the nutrient input in all treatments is the highest,but the available nitrogen,phosphorus,and potassium of the treated soil are less than 2 times and 1 times of the mustard leaves returned during the entire growth period of rice,which shows that the loss of chemical fertilizer in the soil is large,and the fertilization effect of mustard leaves is better.This study shows that the recommended fertilization in the mustard season improves the utilization rate of fertilizers and can ensure the economic benefits of Mustard stems.Phosphorus reduction on the basis of recommended fertilization can improve the utilization rate of phosphate fertilizers.It is best to reduce phosphorus by10%on the premise of ensuring economic benefits of Musrard stems.In addition,the application of NaH₂PO₄ can promote the yield benefit of mustard.Compared with superphosphate in this area,monoamine phosphate has a better effect on the phosphate fertilizer of mustard.In the rice season,1 times the amount of mustard leaves returned is the best.Increaseing this amount will result in a reduction in yield.