Effects of biogas slurry combined with chemical fertilizers on yield,quality of pom-elo and heavy metals in soil
A three-year field experiment was carried out to study the effects of different proportions of pig farm biogas slurry combined with chemical fertilizers on yield and quality of 8-year-old honey pomelo and heavy metals and salinity of soil.The results showed that compared with the application of only fertilizer(TF)(N,P2O5 and K2O were 950.0,600.0 and 850.0 g per plant per year in the forms of urea,calcium superphosphate and potassium sulfate,respectively),the replacement of 25％fertilizer with biogas slurry(TFN25)(based on the usage of nitrogen,insufficient N,P and K nutrients were supplemented by fertilizer)and 50％fertilizer(TFN50)treatment increased yield,and had no negative effect on fruit quality.But replacing 100％fertilizer with biogas slurry(TFN100)had no effect on increasing yield,but decreased the fruit quality.All biogas slur-ry treatments can reduce fruit cracking rate.The replacement of 25％fertilizer by biogas slurry did not in-crease the granulation rate of fruit,while other biogas slurry treatments increased the granulation rate of fruit.With the increase of biogas slurry replacement proportion and application years,the contents of Cu and Zn in the soil increased significantly,but they were lower than the threshold of risk control standard for soil contam-ination of agricultural land.The soil electrical conductivity increased with the increase of biogas slurry replace-ment proportion.In conclusion,application of biogas slurry replacing 25％fertilizer in honey pomelo orchard had better overall effect,which can be popularized in production.However,the effect of long-term application of biogas slurry needs further observation and evaluation.
万方数据
维普
