Effects of Returning Biogas Slurry from Pig Farm on Heavy Metal Contents in Soil and Plants
Returning biogas slurry to farms is the primary method of resource utilization.Due to the presence of various metal elements in biogas slurry,excessive irrigation will cause heavy metal pollution in the soil.At present,in-depth research on the effects of biogas slurry from pig farms on the heavy metal pollution characteristics of cultivated soil and plants and their influencing factors is lacking.In this paper,in Guangxi pig breeding areas,four different types of cultivated land(leafy vegetables,fruit trees,forage grasses,and herbs)and 14 sample plots were selected to study the influence of various irrigation intensities on heavy metals in soil and plants.The results showed that the input intensities of the heavy metals Cu,Zn,and Cd were highest in the 0 to 40 cm surface soils of 14 plots,and their contents and changes in the soil pH were significantly posi-tively correlated with the total amount of biogas slurry irrigation(p<0.05).Among the four types of cultivated land,the con-tents of Cu,Zn,Cd,Pb,and Cr in the edible parts of hybrid elephant grass and water cabbage were significantly positively correlated with the total amount of biogas slurry irrigation.In the process of returning biogas slurry to the field,due to the high input intensity of Cu and Zn and the low enrichment coefficient of plants,the accumulation of Cu and Zn in the soil is faster.The main pollution risks of irrigating biogas slurry on leafy vegetables and fruit trees are Pb and Cd,while the pollution risk to hybrid elephant grass is relatively low.
returning biogas slurry from pig farms to the fieldsoilplantsheavy metal content
万方数据
维普
