Investigation On The Dynamic Change Characteristics Of Harmful Substance From Poultry And Animal Feces In Soil

Output amount of feces of domestic fowl and livestock is huge in our country. Manure’s agriculture utility value is very large because of their rich nutrient resources. Feces played a special role in soil fertility buildup, but the contained poisonous and harmful substance can affect the soil and plant security.Many experts already have carried out at feces contained in the environmental risk physical type and quantity.However, dynamics of harmful substance in feces have less correlation studies.Explore harmful substance concentration changes,degradation and relevant influencing factors are not only indicating risk to environmental,but also can guiding the effective use on feces.Simulated indoor incubation experiment was carried out to explore the concentration dynamics of harmful substance including hippuric acid (HUA),allantoin(All),chlortetracycline (CTC), tetracycline(TTC), oxytetmcyline(OTC), heavy metal(Copper forms) from poultry and animal feces and the effects on fractions of organic carbon including tatal soil organic carbon(TOC),water-soluble organic carbon (WSOC), soil microbial biomass carban(SMBC),particulate organic caoban(POC),easily oxidized organic carban(EOC),extracted humic substances(HE),humic acid(HA) and fulvic acid(FA) in soil were investigated as well. The main resuls were as followed:1. All and HUA acid entering soil with different poultry and animal feces soon entered degrading period, the concentration of all of the treatments rapidly declined at beginning,after that declining speed slowed down and it keep inalterability,but the speed and range of declining are different. At day of 180 the degradation percentage was about 90% and the highest declining rate of all the treatment at 20d. The half-lives of Hippuric acid and Allantoin of chicken feces were 20.87d and 15.51d and them of pig feces were 24.38d and 17.74d. At the end the concentration of HUA and All of pig manure was fewer than chicken manure.2. CTC,OTC and TTC of chicken and pig feces entering soil soon entered degrading period and resembled the L-type curves, the concentration of all of the treatments rapidly declined at beginning,after that declining speed slowed down and it keep inalterability,but the degradation rate and percentage are differents. The half-lives of TTC,CTC and OTC of chicken feces were 49.22d,26.98d and 20.06d and them of pig feces were 98.03d,31.32d,17.43d,so that, the degradation rate of OTC and TTC of chicken fece was higer than them of pig fece,but the situation of CTC was contrary to them.The degradation of CTC was the best and OTC was the weastst in the there kind of tetracy-cline.3. When foreign HUA and All entered soil, micro-degradation and absorption of soil particles occurred at the same time.At the end of training microorganic degradation was the most important reason of HUA and All content lowering and accounted for approximately 69.56% and 78.02% of the declining amount of concentration when the degradation rate were 91.58% and 96.62% at the end of training.4. When foreign tetracy-cline entered soil, micro-degradation, photo-degradation, and absorption of soil particles occurred at the same time while micro-degradation only accounted for a small portion. The most influenced of photo-degradation, micro-degradation and absorption of soil particles were TTC,otc and CTC.With the extension of incubation time, microbiological degradation increased and photo degradation decreased.5. After poultry and animal feces entered into the soil can increase degradation percentage of tetracy-cline,the foreign microorganism from feces has a notable effect and the others effect was not half in increase the degradation. and the largest degradation percentage OTC was increasd.6. The biological activity and toxicity of copper from feces can reduced after feces into the soil and the effects of reduction of pig fece was better than chicken fece.7. HUA,All,CTC,OTC and TTC were significantly degradation of fractions of organic carbon and chicken feces showed a better effect than pig feces, The contents of TOC EOC and SMBC were significantly related to HUA,All and tetracy-cline.at the 0.01 level,and the copper forms were significantly related to WSOC and POC.