| After analyzing the basic character and the heavy metal content of the three kinds of main livestock ( pig manure,chicken manure , cattle manure) and poultry excrement in Fujian tobacco planting area(Longyan city, Sanming city, Nanping city),this article has further studied the effect of application livestock and poultry excrement on the nutrient release characteristics and bioavailability assessment of heavy metals.In this paper,with the inorganic fertilizer application on the basis of a choice of three different sources of livestock and poultry excrement.They were mixed with inorganic fertilizers by a ratio.It was researched that the effect of application livestock and poultry excrement on the content of nutrients in the soils planting tobacco,as well as effect application livestock and poultry excrement on the growth, developmem,nutrient absorption and quality of flue-cured tobacco and the impact of heavy metals in the system via using pot experiment.Result is as follows:1. The livestock and poultry excrement were rich in organic materials and the nutritive elements(N,P,K,Ca,Mg,Fe,Mn,Cu,Zn,and so on ).According to the average content, the content of N and P in the pig manure and the content of K in chicken manure were higher than that in the other.There was great variability in the contents of P and K in the livestock and poultry excrement. The average content of N,P,K were 2.38%,2.30%,1.19% in pig manure, 2.23%,1.48%,2.35% in chicken manure, 1.93%,0.89%,1.61% in cattle manure, respectively.2.The exceed heavy metals limitation standard of copper,zinc,cadmium,arsenic in pig manure were the most serious.The exceed heavy metals were zinc and cadmium in the chicken manure.There were lead and cadmium exceed heavy metals limitation in the cattle manure.According to GB18877-2002 for organic-inorganic compound fertilizers, about 50%,7.14%,22.22% of samples exceeded the limitation of cadmium in the pig,chicken, cattle manure.3.There were significant differences on the decomposition speed of different organic fertilizers in the planting tobacco soil. The decomposition speed of the pig and chicken manure faster than cake quickly.The effect of application of organic fertilizers in the increase of soil available-N was significant. At the end of cultivation,compared with unapplication of organic fertilizers, the increasement of available-N of the soil were 1.99mg/kg,4.02mg/kg,30.32mg/kg and 268.24mg/kg in the application of pig manure,chicken manure,cattle manure,cake,then the content of available-N of cake was the largest,pig manure was the least.The content of available-P in the soil were pig manure>chicken manure>cake>cattle manure.The release rate of available-P of pig manure was largest.The content of available-K changed little during the cultivation.4.The pig manure promoted the adsorptive immobilization of exogenous additive heavy metals lead and cadmium on soil.With the increase of additive concentration, the rate of the adsorptive immobilization of lead on soil was enhanced.There was 50% lead fixed by soil in 30 days of cultivation,then the change range of the rate of the adsorptive immobilization of lead on soil was little after 50 days.At the end of cultivation, the rate of the adsorptive immobilization of lead on soil were 60.27%,71.24%,75.02%,the rate of the adsorptive immobilization of cadmium on soil were 31.57%,8.38%,11.08%,so lead was easier fixed by soil than cadmium.5. The effect of different ratio of livestock and poultry excrement on tobacco plants growth was significantly better than pure chemical fertilizer.At prophase of tobacco plants growth, A2 (1/2 chicken manure, 1/2 pig manure), B2 (1/2 chicken manure, 1/2 cattle manure), C1 (1/3pig manure, 2/3cattle manure), C2 (1/2 pig manure, 1/2 cattle manure), C3 (2/3pig manure, 1/3 cattle manure), D (1/3chicken manure,1/3 pig manure, 1/3cattle manure)were riched in all kinds of nutrients and accelerated the tobacco plants growth,so effect was better than cake.The amount of accumulation of dry matter in plan had a significant difference between the treatment of livestock and poultry excrement and pure chemical fertilizer,and the amount of accumulation of dry matter in plan of A2, B2, C3 were significantly higher than CK2(cake),with A2 had the maximum amount of accumulation of dry matter(96.80g/plant).6. The Cu content of the tobacco leaves was higher than root and stem.The Cu content of the tobacco leaves was lower leaves>central leaves> upper leaves. Different ratio of livestock and poultry excrement treatments had a large change range on the Cu content of the tobacco leaves,B1(137.21 mg/kg) was maximum, A2 (highest 89.72 mg/kg) was minimum. The Zn content of the tobacco leaves of different ratio of livestock and poultry excrement treatments were higher 0.92～3.69 percentage points than CK1(the pure chemical fertilizers). The Zn content of the tobacco leaves(without C3)was lower leaves>central leaves> upper leaves. The Pb content of the tobacco leaves of different ratio of livestock and poultry excrement treatments were lower 18.73%～43.82% than CK1, so the livestock and poultry excrement could obviously decrease heavy metal lead which tobacco plants absorbed.The leaf of tobacco was the most important part in absorbing heavy metals of Cu,Zn,Pb,Cd.
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