水蓼种植下猪粪处理土壤剖面磷组分与磷酸酶活性变化OA北大核心CSTPCD

The excessive application of swine manure in agricultural production can lead to a phosphorus surplus and increased risk of phosphorus losses from soil.In this study,a 3-year field microcosm experiment was conducted to investigate the changes in phosphorus forms and phosphatase activities in soil treated with swine manure and planted with the phosphorus-enriched plant Polygonum hydropiper.Ultimately,the goal of this research was to provide a scientific basis for preventing soil phosphorus losses and enhancing efficient phosphorus extraction by phosphorus-enriched plants such as P.hydropiper.The field microcosm simulation experiment consisted of P.hydropiper planted in soil with three swine manure treatments(1,2,and 3 kg·m-2)and a control without swine manure,each with three replicates.During the 3-year field experiment,the aboveground biomass of P.hydropiper and the amount of phosphorus accumulated in its tissues were measured annually.The aboveground parts of the plant and soil at depths of 0-10 cm,10-20 cm,20-30 cm,and 30-40 cm were collected every year,and the phosphorus content of the plant and the phosphorus saturation,phosphorus composition,pH,and phosphatase activity along the soil profile were determined.The changes in phosphorus forms and phosphatase activity in the profile of soil treated with swine manure and planted with P.hydropiper were analyzed.The results showed that:1)During the 3-year field experiment,the aboveground biomass of P.hydropiper increased with increasing swine manure application,as did the amount of phosphorus accumulated in the tissues.In the 3 kg·m-2 swine manure treatment,the amount of phosphorus in the aboveground parts of P.hydropiper reached 200.31,195.97,and 195.24 mg·plant-1 in the first,second,and third year,respectively,remaining stable over the years.2)During the 3-year experiment,the rate of increase in the phosphorus content in soil in the 0-20 cm and 20-40 cm layers was relatively slow.In the 1 and 2 kg·m-2 swine manure treatments,the soil phosphorus saturation level was 25%lower than the critical value of soil phosphorus loss.3)With increasing swine manure application,the phosphorus contents in the 0-10 cm and 10-20 cm soil layers increased,and the application of swine manure at higher concentrations for 3 consecutive years enhanced phosphorus mobility.The pH values of the 0-10 cm and 10-20 cm soil layers gradually decreased,and the phosphatase activities in these layers increased with increasing swine manure application,reaching the highest levels in the 3 kg·m-2 swine manure treatment.In conclusion,continuous application of swine manure increased the phosphorus contents in the 0-10 cm and 10-20 cm soil layers and enhanced the mobility of phosphorus in the soil profile,and the increase was the largest in the 3 kg·m-2 treatment.P.hydropiper demonstrated a strong ability to extract excess phosphorus from swine manure-treated soils.Under P.hydropiper cultivation,increasing swine manure application led to a gradual decrease in pH in the 0-10 cm and 10-20 cm soil layers,accompanied by higher activities of acid phosphomonoesterase,alkaline phosphomonoesterase,phytase,and phosphodiesterase in soil.P.hydropiper extracted and accumulated phosphorus,and promoted the transformation of soil phosphorus from less effective fractions to more effective ones,thereby reducing the risk of phosphorus losses from soil.