草业学报2025，Vol.34Issue(4)：64-81,18.DOI:10.11686/cyxb2024215
净化沼液滴灌对砂壤土质量、青贮玉米生产力的影响及安全消纳容量分析
Effect of purified biogas slurry drip irrigation on sandy loam soil quality,silage maize productivity and analysis of safe application rate
摘要
Abstract
Ningxia's forage and livestock industries currently face multiple issues;forage plant breeding and production is below requirement,the soil quality in the forage production areas is declining,the yields are modest,and the application of a large amounts of manure as fertilizer has both environmental and health risks.In this study,a multi-stage filtration process was used to obtain purified biogas slurry,and an experiment was set up to apply the slurry at different rates(0,225,450,675,900,1125,1350 m3·ha-1)by drip irrigation.The purified slurry liquid fertilizer was applied to a silage maize crop,and its effects on soil quality and silage maize yield were systematically studied to determine the safe application rate.The results showed that soil pH,the contents of total salt,available nitrogen,available phosphorus,available potassium and heavy metals including copper(Cu),zinc(Zn),lead(Pb),cadmium(Cd)and chromium(Cr)increased significantly with increased biogas slurry application rate,while the content of soil organic matter initially increased and then decreased with increased application rate.Soil organic matter level was highest under the 900 m3·ha-1treatment.This treatment also significantly increased the content of soil water-stable macroaggregates(＞0.25 mm),mean weight diameter,geometric mean diameter,microbial biomass carbon content,enzyme activity and quality index.The yield,dry matter content and starch content of silage maize increased initially and then decreased with successive increases in the application rate of purified biogas slurry.A linear regression equation showed that a purified slurry application rate of 806-925 m3·ha-1best promoted the yield and quality of silage maize.In addition,the contents of Cu,Zn,Pb,Cd and Cr in silage maize showed an increasing trend with increase in the application rate of purified biogas slurry.However,heavy metal levels observed were far lower than the permissible limits in animal feed.Based on this study,it was concluded that the soil quality index and silage maize productivity were the highest under the slurry application rate of 900 rn3·ha-1.Based on this drip application rate,and the permissible levels of the heavy metal element,Cd,the soil environmental absorption capacity can be calculated.After continuous drip irrigation for 25 years,the soil heavy metal content would not exceed the standard.Furthermore,based on the second national soil census Ningxia soil salinization division standard,it can be calculated that continuous drip irrigation for 19 years would not result in soil secondary salinization.关键词
净化沼液/青贮玉米/产量/土壤质量指数/重金属Key words
purified biogas slurry/silage maize/yield/soil quality index/heavy metal引用本文复制引用
蒋鹏,李磊,解昊郡,徐得甲,王锐,虎强,孙权..净化沼液滴灌对砂壤土质量、青贮玉米生产力的影响及安全消纳容量分析[J].草业学报,2025,34(4):64-81,18.基金项目
奶牛粪污生物强化处理与分类再利用创新模式研究与示范(2022BEG02004)资助. （2022BEG02004）
