The Effect Of The Content And Distribution Of Heavy Metals In The Soils Around Pig House And Inside Dust Induced By Large-scale Pig Breeding

In order to study the effect of pig breeding on the accumulation of heavy metals in the soil,the content of heavy metals in feed,feces and dust of four pig farms(pregnant sows,maternity houses,nursery houses,fattening houses)in five scale farms in Hunan Province After analysis,the effects of accumulation of heavy metals on the heavy metals in the soils were studied.Selected from the side of the outer wall of the pig 1m on the side of the axis of the same distance of 5 points to the center as a center to collect 20*20cm square soil samples to quadruple mixed into the average sample,which belonged to the soil not affected by human activities The contents of Cu,Zn,Hg and Cr in soil samples were analyzed by laboratory,and the correlation between dust and heavy metal content in soil was analyzed.The results were as follows:(1)According to the China Organic Fertilizer Industry Standard(NY525-2012)and German Composting Standard,the contents of Cu and Zn in the feces collected from the four piglets exceeded the standard and should not be directly used as organic fertilizer.The contents of Cu and Zn in the stool samples collected from four pig houses were the highest in piglet manure.The pig's dust has high copper and high zinc characteristics.In addition to the Hg content in the fertilizer,the heavy metal content of the pig's dust is higher than that of the corresponding feed.The content of Cu in the dust of each pig was lower than that of the corresponding feces,but the contents of heavy metals such as As,Hg and Cr were higher than those of the corresponding feces.In addition to Hg,the contents of heavy metals in feed,dust and feces were sorted as follows: Zn>Cu> Cr> As> Cd.From the correlation coefficient,in addition to Cd,As,the relevance of feed and dust is greater than the correlation between feces and dust.Unlike the environment and feed,the heavy metals in the dust are different,but the whole,the feed Cu,Zn,Hg,Cr is the main source of the corresponding heavy metals in the dust.(2)The contents of Cu,Zn,Hg and Cr in the soil of four pig houses increased with the increase of the use time of pig house,and the accumulation of heavy metals increased with the increase of the service life of pig.The correlation analysis showed that the Cu content in the soil was close to that of the semi-open pregnant sow and the fattening house,and the semi-open pig The correlation between Zn and Hg was more likely to accumulate in the soil beside the pig house,but the correlation between Cr and the Cr content in the soil was not high.The heavy metals Zn and Hg in the fattening were positively correlated with the contents of heavy metals in the soil(P <0.05).According to the cumulative values of Hg and Cr in the soils of four pig houses,the order of accumulation was longer than that of pregnant sows> fertilizers> maternity ward> nursing homes.(3)The results showed that with the increase of the useful life of the pig house,the Cu and Hg in the soil of the pregnant sow were higher than those in the soil,Zn is easy to form pollution,fat in the soil next to the soil is prone to pollution,while the conservation of soil next to the four kinds of heavy metals did not appear excessive phenomenon.