摘要
为探索山东省南四湖沿岸麦玉轮作区玉米季内减少土壤无机氮素淋溶和径流损失的施肥策略,降低其对湖区水质产生的潜在威胁,采用田间原位安装淋溶水采集器和地表水径流池收集水样结合室内分析不同形态氮含量的方法,研究了不同施肥模式下无机氮素淋溶和径流损失特征。结果表明:土壤淋溶水量及地表水径流量与降水呈显著正相关关系,其水量受秸秆类物质还田的影响;硝态氮(NO3--N)与铵态氮(NH4+-N)随地表水径流损失的浓度及总量均明显高于淋溶水,由径流方式损失的氮素占2/3以上,是氮素以水溶液形式流失的主要途径;淋溶和径流均以NO3--N损失为主(径流损失中NO3--N占总量的82.9%—90.8%,淋溶损失中NO3--N占63.5%—72.9%),地表径流水NO3--N浓度对水质有较大影响,但土壤淋溶水NO3--N浓度对地下水污染不构成威胁;农民习惯施肥处理在玉米整个生育期淋溶和径流氮损失最高。在保证玉米产量前提下,降低氮素流失造成湖区的污染,平衡施用氮磷钾肥、施用控释氮肥、有机替代无机和秸秆还田等措施均可在沿南四湖区农田使用。
Nansi Lake is the largest lake in Shandong province and the northern area of China, which is an important buffer lake of the South-to-North Water Diversion Project (east route). Eutrophication has become the central problem of water environment in Nansi Lake where the eutrophic state is from mesotrophic state to hypereutrophic state. A field study was conducted to investigate the characteristics of inorganic N loss by leaching and runoff during the maize growing season in the Nansi Lake Basin, and determine fertilizer application strategies to reduce N losses and their potential threats to lake water quality. Under different fertilization patterns ( In this experiment, 7 different fertilization treatments were installed, such as follows: (1) CK: no fertilizer was applied to soil; (2) FP: farmer's practice of traditional fertilization; (3) PK: in this treatment, only phosphate and potash fertilizer applied to soil; (4) OPT: nitrogen, phosphate and potash fertilizers were mixed to a balanced nutrition; (5) CRF: in the treatment, controlled-release nitrogen fertilizer replaced common nitrogen fertilizer, and other nutrition was invariable; (6) 80% OPT+M: total amount of nutrition applied to soil was equal to the 4th treatment, but 20% of total inorganic nutrition was replaced by that existed in the organic matter-poultry excrement; (7) OPT+St: a balanced N, P and K nutrition was applied to soil, and total amount was equal to the 4th treatment, meanwhile, wheat straw was returned to cover the soil surface ), Collectors for leaching and surface runoff water were installed in-situ in each treatment. Water samples were collected for analysis of different forms of inorganic nitrogen in laboratory. The results indicated a positive correlation between quantity of leaehate water, surface runoff water and precipitation. The amount of water was affected by substances such as wheat straw; The Concentration and total amount of NO^-3-N and NO^-4-N losses from runoff were
出处
《生态学报》
CAS
CSCD
北大核心
2011年第12期3488-3496,共9页
Acta Ecologica Sinica
基金
国家科技支撑计划项目(2007BAD87B05)
公益性行业(农业)科研专项(201103003)
现代小麦产业技术体系专项(CARS-03)
山东省科技支撑体系建设专项资助(2007GGC02002)
关键词
施肥模式
南四湖农田
无机氮素
流失
fertilization patterns
fields of Nansi Lake Basin
inorganic nitrogen
loss