Based On Big Data Analysis, The Priority Of Pollution Prevention And Control In The Whole Process Of Aquaculture

With the increasing intensification of pig breeding,the fecal emission from pig farms tends to be concentrated,and the pollution from pig breeding has become the biggest problem of non-point source pollution in China's agriculture.The most important method to deal with breeding manure is returns it to the field without harm.However,for a long time,China has not formulated the policy of"depending on the land to raise",As a result,the scale of farming does not match the scale of farmland,and a large number of concentrated discharge of breeding manure far exceeds the carrying capacity of the land,so it is difficult to comprehensively utilize the manure.Besides will waste for disposal,due to the breeding waste processing technique and technology involved in the link,is more,different craft combination can also affect the back of the recycling effect,therefore,to understand different pollutants in different link,under the process of cutting,the transfer and change situation,summed up the pollution prevention priority sequence,reasonably come to the waste treatment mode,It is the basis for the safe return of feces to the field.Of this study was carried out on the existing literature research,the use of social network analysis,the analysis of main pollutants in waste in existing research types,analysis of the in pigs all process(source,process,resource utilization)of the concentration and cutting technology,summarizes the technology conditions of each link and reduction rate,comprehensive breeding whole process pollution control priority sequence,The optimal scale analysis and Meta analysis methods were used to propose a technical plan for the prevention and control of feces in order to provide theoretical basis for the safe return of feces to the field.The main results are as follows:(1)The research hotspots in the field of pollution control of pig breeding in the past 20years are as follows:first,waste form;The second is the processing technology.There are three main research directions of aquaculture pollution and control:(1)To reduce the environmental pollution risk of aquaculture manure by using technical methods;(2)Pollutants in pig farm waste water;(3)Pollutants brought by breeding manure returning to the field.The main pollutants in pig breeding include N,P,heavy metals and antibiotics,in which TN,ammonia nitrogen,TP,Cu,Zn,tetracycline,sulfonamides and fluoroquinolones antibiotics are specifically concerned.(2)Priority for pollution prevention and control of N and P.N and P,as a large number of elements needed for crops,only need to meet the conditions of harmless,as far as possible to achieve the use of farmland,usually used for farmland after mixing feces and sewage anaerobic,or feces composting,sewage anaerobic for farmland;If there is not enough farmland,the nutrients in sewage will need to be reduced until they meet the discharge standards.After treatment,about 2?23%of the initial TN and 1?59%of the initial TP of the aquaculture manure entered the farmland ecosystem through the application of organic fertilizer,biogas slurry and biogas residue.Waste after solid-liquid separation,most P into the solid waste,most of the N into the liquid sewage,so in addition to the P needs to be fully effective solid-liquid separation,remove the solids in the waste,although far less than N,P concentration in the wastewater but P for eutrophic water response sensitivity is much higher than N,as a result,in sewage treatment,the more need to pay attention to the processing of P.N and P pollution prevention and control of pig breeding should be carried out in the process of processing.The priority of piggery feeding is secondary.(3)Priority for prevention and control of antibiotic contamination.More than 90%of the antibiotics could be degraded through composting and anaerobic treatment.After 30 days of natural degradation in the field,the final residual antibiotics in the field accounted for about 1-4%of the total antibiotics in the initial feces.Pig-breeding pollution control priority to technology processing link using antibiotics cutting technology to remove,followed by natural degradation of soil antibiotics,but the need to control waste fertilization frequency and farmland management measures,to prevent the circulation of antibiotics into the water,the last source for breeding,the breeding source pollution prevention and control to antibiotics.(4)Priority for prevention and control of heavy metal pollution.The addition of Zn and Cu in the feed was relatively the most,and the Cu and Zn in the pig feed exceeded the standard seriously,followed by As.The concentrations of Zn and Cu in pig manure and wastewater are also relatively the highest.In terms of species,the main order of attention for the control of heavy metals in pig breeding is Zn,Cu and As.In addition,due to the heavy metals strong stability,processing process of compost can effectively reduce the total heavy metal passivating heavy metals cannot,removal of heavy metals in wastewater is mostly adopt the way of precipitation,flocculation,heavy metals in farmland is more difficult to remove,therefore,live pig breeding of heavy metal pollution prevention and control priority at source,of heavy metals from the source code to add,Reduce subsequent pollution.(5)Pollution control technology recommendation of pig breeding.After solid-liquid separation,composting and anaerobic technology were applied to prevent and control the pollution of N,P and antibiotics.The purpose of compost is to reduce the concentration of pollutants(antibiotics)and to retain nutrients(N,P)for future recycling and returning to the field.The anaerobic purpose is to reduce the concentration of pollutants(antibiotics,N,P),to meet the sewage discharge standards.Therefore,the removal of antibiotics should be given priority in composting technology,followed by the retention of N and P.The order of anaerobic concern for contaminants is P>N>antibiotics.In summary,the use of container composting,controlled C/N ratio between 20 and 25,temperature above 60?,and the addition of physical or chemical additives to the composting method can maximize nutrient retention while removing antibiotics as much as possible.Anaerobic fermentation should adopt sequential batch feeding,temperature control between 25?45?,initial concentration of antibiotics in the range of 10?60 mg·kg^-1.