农业环境科学学报2025，Vol.44Issue(4)：964-974,11.DOI:10.11654/jaes.2024-0595
长期施肥对红壤侵蚀坡耕地重金属积累及其有效性的影响
Effects of long-term fertilization on heavy metals accumulation and bioavailability in sloping cropland of red soil
摘要
Abstract
In order to investigate the long-term effects of pig manure and chemical fertilizers on the accumulation and bioavailability of heavy metals in eroded red soil sloping fields,a long-term erosion plot experiment(2012-2023)was conducted at the Red Soil Ecological Experiment Station of the Chinese Academy of Sciences.Soil samples were collected from the topsoil layer(0-20 cm)in different years(2012,2015,2018,2020,and 2023)and from the vertical profile(1 m depth)in 2023.The changes in soil pH,soil organic carbon(SOC),and the total and bioavailable contents of four heavy metals(Cr,Cu,Zn,Cd)were analyzed under three treatments regimes over a 12-year period:no fertilizer application(CK),chemical fertilizer alone(NPK),and combined application of pig manure and chemical fertilizer(NPK+PM).The results showed that,compared to the initial soil conditions,the NPK treatment reduced topsoil pH by 0.2 units to 0.6 units and decreased SOC content by 1.0 g·kg-1 to 1.9 g·kg-1.In contrast,the NPK+PM treatment increased topsoil pH by 0.2 units to 0.6 units and raised SOC content by 0.1 g·kg-1 to 3.0 g·kg-1.Relative to the CK treatment,the NPK treatment significantly increased the available Cr content in the topsoil by 446.2％to 851.2％(P＜0.05).The NPK+PM treatment significantly increased the total Cu and Zn content in the topsoil by 76.3％to 129.6％and 71.2％to 125.8％(P＜0.05),respectively,and significantly raised the available Cr,Cu,and Zn content in the topsoil by 335.0％to 1 213.4％,162.3％to 1 373.2％,and 275.8％to 2 457.0％(P＜0.05),respectively.By 2023,the total Cu content in the soil reached 56.8 mg·kg-1,exceeding the risk control screening value for agricultural land(50.0 mg·kg-1).Furthermore,the NPK+PM treatment significantly increased the bioavailability of Cu and Zn in the subsoil(20-100 cm)by 53.9％to 354.2％and 66.3％to 368.2％,respectively(P＜0.05).Correlation analysis showed that under the NPK treatment,the effective states of Cr,Cu,Zn,and Cd,as well as the total Cd content in the soil,were highly significantly positively correlated with soil pH and SOC content(P＜0.01).Under the NPK+PM treatment,the effective states and total amounts of Cu,Zn,and Cd,as well as the effective state of Cr,were highly significantly positively correlated with soil pH and SOC content(P＜0.01).The study concluded that applying chemical fertilizer alone to eroded red soil sloping fields can lead to topsoil acidification and depletion,promoting heavy metal activation and accumulation.On the other hand,the long-term combined application of pig manure and chemical fertilizer significantly promoted the enrichment of heavy metals in the topsoil and the activation of heavy metals in the soil profile.Therefore,in agricultural practices,it is recommended to optimize the application rates of chemical fertilizers,use treated pig manure and implement soil and water conservation measures to reduce the risks of heavy metal accumulation and non-point source pollution.关键词
侵蚀坡耕地/红壤/长期施肥/猪粪/重金属/生物有效性Key words
eroded sloping cropland/red soil/long-term fertilization/pig manure/heavy metal/bioavailability分类
资源环境引用本文复制引用
李嘉奇,郭自春,汪亚及,高磊,彭新华..长期施肥对红壤侵蚀坡耕地重金属积累及其有效性的影响[J].农业环境科学学报,2025,44(4):964-974,11.基金项目
井冈山农高区省级科技专项"揭榜挂帅"项目(20222-051261) （20222-051261）
中国科学院战略先导专项(XDA0440404) （XDA0440404）
国家自然科学基金项目(42077012)Jinggang Shan Agricultural Hi-tech District Project(20222-051261) （42077012）
Strategic Priority Research Program of Chinese Academy of Sciences(XDA0440404) （XDA0440404）
National Natural Science Foundation of China(42077012) （42077012）
