长期施用沼肥对设施菜田土壤养分和盐分累积量的影响

为研究规模养猪场沼液沼渣在农田施用对土壤养分及盐分含量累积的影响,以安康市某养猪场农业园区施用沼液设施菜田土壤为研究对象,以当地常规施用化肥设施菜田为对照,定点采集施用沼肥区和对照区0 a、1 a、3 a、5 a和7 a的设施菜地土壤,分别测定土壤中碱解氮、有效磷、速效钾、有机质、全铜、全锌质量分数及电导率和pH。结果表明,随着沼液沼渣施用年限的增加,土壤中碱解氮、有效磷、速效钾、有机质、全铜、全锌质量分数和电导率均相应增加,7 a后分别达96.1 mg/kg、91.5 mg/kg、73.7 mg/kg、11.9 g/kg、118.5 mg/kg、263.4 mg/kg和0.366 mS/cm,分别是未施用沼液沼渣土壤中各成分含量的3.4倍、1.5倍、3.3倍、1.3倍、3.9倍、1.88倍和4.74倍,说明施用沼液沼渣能有效增加土壤养分含量,同时土壤养分和盐分快速累积,对土壤环境带来较大的污染风险。

Study on Effect of Long-term Application of Biogas Manure on Soil Nutrients and Salt in Protected-land Vegetable Field

In order to study the effect of long-term application of biogas manure on soil nutrients and salinity in large-scale pig farms,vegetable fields with application of biogas from pig farms in agricultural park of Ankang area were taken as object.The vegetable fields with applicaiton of the chemical fertilizer as control,the soil was collected from the fixed point land with application of biogas liquid and CK 0,1,3,5 and 7 years,the mass fractions of alkali-hydrolyzed nitrogen, available phosphorus, available potassium,organic matter,total copper and total zinc in soil were determined.The results showed that the mass fractions of alkali-hydrolyzed nitrogen,available phosphorus,available potassium,organic matter,total copper,total zinc and conductivity increased with increase of years of application of biogas liquid and residue. Seven years later,it respectively reached 96.1 mg/kg,91.5 mg/kg,73.7 mg/kg,11.9 g/kg,118.5 mg/kg,263.4 mg/kg and 0.366 mS/cm,respectively,which was 3.4 times of the content of each component in the soil without biogas liquid. 1.5 times,3.3 times,1.3 times,3.9 times,1.88 times and 4.74 times,It showed that the application of biogas liquid and residue could effectively increase the content of soil nutrients,while the rapid accumulation of soil nutrients and salt would cause serious pollution risk.