Effects Of Long-term Fertilization On Soil Enzyme Activity And Nutrient Of Wheat-maize Intercropping System

Wheat-maize intercropping is an important multi-cropping pattern in Hexi oasis irrigation area,the study has showed that long-term fertilization will have a profound impact on soil properties.This paper is based on long-term experiment to study the effected of soil enzyme activity and soil nutrients by fertilizer and the succession law of soil enzymes and soil physical throughout the growing period of Wheat-maize intercropping,as well as the correlation between them,provided a scientific basis for further discussion soil enzyme as an sensitive index to fertility and reasonable fertilizer management.The main conclusion of the study are as follows:1 Effects of fertilization on soil enzyme activities:Fertilizing of the growing period of wheat-maize intercropping affect the activity of soil invertase more obvious,single application of the fertilizer treatments on the activity of invertase shown as O(green manure)>SW(straw)>N(nitrogen)>M(farm manure), specially,single application of O(green manure) is the most obvious to improvement the invertase activity.The combined application of organic fertilizer and N over than organic fertilizer and organic fertilizer is more conducive to improvement the invertase activity, especially,the combined application of O+N is the most.Effects of fertilization of the growing period of wheat-maize intercropping on soil catalase activity shown as:in single application,it is M>O>SW>N;in combined application,the combined application of organic fertilizer and organic fertilizer better than organic fertilizer and N to improve catalase activity,especially,combined application of M+O+N is the most.It is not enough to significantly that effects of fertilization of the growing period of wheat-maize intercropping on soil urease activity,single application O is the greatest impact,combined application of organic fertilizer and N show a certain role in promoting soil urease activity.Effects of fertilization of the growing period of wheat-maize intercropping on soil phosphatase activity showns as:single application O,M is the greatest impact,O>M>SW>CK>N,the combined application of organic fertilizer and N to improvement the phosphatase activity. better than organic fertilizer and organic fertilizerSoil enzyme activities changes during whole growing period of wheat-maize intercropping.Invertase activity showed lower in wheat pre-sowing,increased in jointing stage of wheat,the maximum in post-harvest of wheat and post-harvest of maize reduced, a 'low-high-low' single-peak type.Catalase activity showed pre-sowing of wheat and post-harvest of maize lower,jointing stage of wheat,grain-filling stage of wheat and post-harvest of wheat high,but also for the single-peak type.Urease activity showed pre-sowing of wheat and jointing stage of wheat increased,and then began to decrease,the minimum post-harvest of wheat,post-harvest of maize increased.Phosphatase activity showed the trend of double peak tape,lower in pre-sowing of wheat,increase in the jointing stage of wheat,reduced grain-filling stage of wheat,elevated post-harvest of wheat,post-harvest of maize to reduce.2 Effects of fertilization on soil organic,available nitrogen,phosphorus and potassium content:The single application of the fertilizer treatments effects of fertilization on soil organic,available nitrogen,phosphorus and potassium content shown as follows:organic fertilizer or no fertilizer(CK) more than single application of N fertilizer,effects of single application on soil organic,available phosphorus and potassium content shown as follows: Organic fertilizer and no fertilizer(CK) more than single application of N fertilizer,in which organic matter,available phosphorus and potassium affect the performance for M＞O＞SW＞N,which is similar with single application of organic fertilizer on the impact of activity of hydrogen peroxide and phosphatase,On the impact of nitrogen followed by processingO＞M＞SW＞N,to the most obvious single application of O,O with the single application of urease activity of the enzyme activity and sucrose similar to the impact of the law.The combined application organic fertilizer and organic manure fertilizers than organic manure fertilizer and N can be enhanced with the improvement of the available nitrogen,phosphorus and potassium content.Soil organic matter and available phosphorus showed double peak tape in the growth period;available potassium higher in the jointing stage of wheat,lower in post-harvest of wheat,increased slightly in post-harvest of maize. available nitrogen higher in pre-sowing of wheat,other developmental stages is similar to available phosphorus and organic matter in soil laws.3 Effects of fertilization on yeild: Farming fertilizer and green manure can increase crop yield,as soon as N fertilizer effects on crop yield larger,and its yeild is the highest in all fertilizer treatments,the characteristics showed similar with activity of invertase,urease and phosphatase in the soil. Effects of fertilization on yield of wheat to the most obvious single application of M, organic manure and N fertilizer on wheat yield increase in a certain role,of which fertilizer M+O+N the most obvious,the yeild reached 3062 kg.hm^-2. Effects of fertilization on yield of maize,O is the most obvious in the single application of organic.Effects of fertilization on the yield of maize and wheat shown as the combined application of organic manure and N fertilizer than organic manure and organic manure higher,which the treatment with N combined application is higher,the combined application of O+N up to 15622 kg.hm^-2,SW + N fertilizer less than the combined application of farm manure or green manure and nitrogen fertilizer,but higher than the single application of SW,effects of SW single application on the yield for maize and wheat is the lowest.Application of organic manure can increase soil for fertilizer on crop capacity and soil enzyme activity to increase crop yields.Organic manure and nitrogen fertilizer application with the appropriate amount of crop yield and soil nutrient balance of ecosystems is useful to supply,Maize grain yield reduction in the current half of the amount of nitrogen fertilizer,the amount of fertilizer is higher than nomal nitrogen rate grain yield or maintain a high level,in this experiments to the treatment of O+N is the highest yield.However,when the combined application of organic mature and organic mature(including two or three kinds of the application of organic mature and organic mature) continue to increase the amount of nitrogen fertilizer consumption decreased,the grain yield no significant,lower utilization rate of fertilizer significantly reduced, indicating that there are a lot of space to reduce the amount of chemical fertilize in grain production.This study shows that organic manure and nitrogen fertilizer combined application is the best treatment,can be to ensure that high income while reduce the amount of nitrogen fertilizer,is both economic and ecological benefits of the application system.