Early Warning Of Livestock Manure Load And Suitability Analysis Of Spatial Layout In My Country

With the rapid development of my country’s social economy,environmental pollution has become more and more serious.In recent years,my country has implemented a series of policies and systems in order to accelerate the utilization of manure resources in the livestock and poultry breeding industry and promote the sustainable development of animal husbandry.For the livestock and poultry breeding industry in my country’s provinces,timely grasp of the characteristic distribution of livestock and poultry manure and reasonable planning of the layout of the livestock and poultry breeding industry are particularly important for the effective prevention and control of environmental pollution in the breeding area.At present,most studies on pollution of livestock and poultry manure are based on a single species or on a small regional scale,while relatively few studies have been conducted on a large-scale macroscale nationwide.For the assessment of the suitability of the spatial layout of livestock and poultry breeding,the index selection is mostly focused on the impact on the water and soil resources and the environment,but the environmental impact value that has been caused so far has not been considered.This article first uses the pollution coefficient method to estimate the amount of livestock manure produced,the amount of pollutants produced,and the amount of pollutants lost in 2017 based on the data from the China Animal Husbandry Yearbook.On this basis,analyze the distribution characteristics of livestock and poultry manure emissions across the country in 2017,and uniformly convert the amount of manure produced by various livestock and poultry into pig manure equivalent,and calculate the pig manure equivalent carrying load per unit of arable land and the warning value.Refer to the relevant standards to obtain the warning levels corresponding to the provinces across the country.In addition,using the combination of analytic hierarchy process and entropy method,starting from the three aspects of resource environment,social development,and livestock and poultry breeding,10 evaluation indicators are selected to construct an evaluation system for the suitability of the spatial layout of livestock and poultry breeding in my country,and 31 provinces across the country are scored.The results show:1)In 2017,the total amount of livestock manure produced nationwide was 2.36 million tons,of which manure accounted for 66.47% and urine accounted for 33.53%.Cow manure produces the most and poultry manure produces the least.Among the 31 provinces studied,Sichuan Province,Shandong Province,and Henan Province produce more manure.The province with the largest amount of livestock manure production is Sichuan Province,with the largest production volume of 1.95 million tons.2)In 2017,the output of COD,TN,and TP in livestock manure in 31 provinces across the country reached 58.04 million tons,12.46 million tons,and 4.82 million tons,respectively.In terms of specific indicators,cow dung has the highest content of pollutants,followed by poultry dung,which is mainly due to the fact that the daily excretion coefficient of cow dung is much higher than other livestock species;Sichuan,Shandong,and Henan have more livestock and poultry farms.,And the amount of pollutants lost is directly proportional to the amount of pollutants generated,resulting in a considerable contribution rate of the pollutants generated and lost in the abovementioned regions.The total loss of COD,TN,and TP in Sichuan,Henan,and Shandong alone accounted for 19.37%,21.68%,and 24.31% of the total loss of pollutants in 31 provinces(cities,autonomous regions)across the country.3)Assuming that the manure produced can be absorbed by the effective arable land that year,the average pig manure equivalent carrying capacity per arable land area of the mainland China in 2017 is 28.01,and the average pig dung equivalent early warning per arable land area is 0.71.According to the classification,the overall national warning level is at level III.From the perspective of the way of arable land consumption,the current production of livestock and poultry manure in 31 provinces(cities,autonomous regions)across the country has already affected the current overall environment;The load of pig manure equivalent of farmland livestock and poultry manure varies greatly between different provinces.Most of the provinces studied in this paper are in the first-level early warning(no threat to the environment),and the provinces that have reached the second-level early warning(threat to the environment)are Tianjin,Liaoning,and Liaoning.Jiangxi,Shandong,Hunan,Guangxi,Sichuan,Guizhou,Yunnan,and Gansu have a slight impact on the environment;Guangdong and Hainan have reached level III warnings,which have already caused a certain threat to the environment;Beijing and Fujian have reached level 4 warnings.It has already had a serious impact on the environment;Tibet and Qinghai have reached level VI early warning,and local livestock and poultry manure poses a serious threat to the environment.According to the calculated warning level,each province should make full use of livestock and poultry manure resources according to its own situation,especially in areas with high warning values,and timely control the total amount of livestock and poultry breeding and pollution prevention and control measures4)The final score range for the suitability of the spatial layout of livestock and poultry breeding in my country is 52.50-82.67.The lowest score is Ningxia Hui Autonomous Region,and the highest score is Sichuan Province.According to the index evaluation system established in this article,the main factors affecting the suitability of livestock and poultry breeding in various provinces are resources and environmental indicators,among which the area of arable land and the amount of water resources are the dominant factors.The provinces with low scores are not completely unsuitable for the development of the livestock and poultry breeding industry.In the future,largescale breeding can be formed by integrating scattered households,and technical means can be used to treat livestock and poultry manure to improve the suitability of livestock and poultry breeding.Then the grassland resources can be fully utilized to improve the suitability of livestock and poultry breeding.