| 引用本文: | 雷豪杰,李贵春,丁武汉,徐驰,王洪媛,李虎. 设施菜地土壤氮素运移及淋溶损失模拟评价[J]. 中国生态农业学报(中英文), 2021, 29(1): 38-52 |
| LEI Haojie,LI Guichun,DING Wuhan,XU Chi,WANG Hongyuan,LI Hu. Modeling nitrogen transport and leaching process in a greenhouse vegetable field[J]. Chinese Journal of Eco-Agriculture, 2021, 29(1): 38-52 |
| DOI： | 10.13930/j.cnki.cjea.200570 |
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| 摘要: 设施菜地因大水大肥管理方式导致的氮素淋失已成为当前关注焦点。探寻氮素淋失阻控技术需要首先探明土壤中NO3--N的运移和淋失过程，找到淋失阻控的关键点，从而实现蔬菜栽培高产量低环境成本。本研究以京郊设施菜地黄瓜-番茄轮作系统为研究对象，通过田间试验获取土壤温度、湿度、NO3--N含量等数据，对反硝化-分解（DNDC）模型进行参数校验，并以农民常规种植模式为基线情景，设置改变土壤基础性质、灌溉量、施氮量等不同情景，运用DNDC模型对设施菜地系统土壤氮素运移及淋溶损失进行定量评价。结果表明：经验证后的DNDC模型能够较好地模拟蔬菜产量、5 cm土壤温度和0~20 cm土壤孔隙含水率变化以及NO3--N的迁移过程，是模拟和评价氮素运移和损失的有效工具。模拟不同情景表明，设施菜地0~60 cm土壤NO3--N累积主要受灌溉水量和氮肥施入量的影响，此外土壤pH和土壤有机碳的变化也是影响NO3--N运移的重要因子。节水节肥是设施菜地氮素淋失减量的最有效方法，相比常规措施，同时减少20%灌溉量和20%施氮量可明显降低59.04%的NO3--N淋失量。同时，在节水节肥的基础上改变灌溉方式并提高20%土壤有机碳含量，在保证蔬菜产量的前提下，能够进一步降低69.04%的NO3--N淋失量。可见，DNDC模型为设施菜地NO3--N淋失评价和阻控提供了一个较好的解决方案。在当前重点关注减氮节水等管理措施的同时，提高土壤本身的质量，不失为一种更有效的减少设施菜地氮素淋失的途径。 |
| 关键词: 设施菜地 氮淋失 水氮控制 土壤有机碳 DNDC模型 |
| 中图分类号:S19 |
| 基金项目:国家重点研发计划项目（2018YFD0800402，2016YFD0800101）和国家自然科学基金项目（41671303）资助 |
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| Modeling nitrogen transport and leaching process in a greenhouse vegetable field |
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LEI Haojie1, LI Guichun2, DING Wuhan1, XU Chi1, WANG Hongyuan1, LI Hu1
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1.Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China;2.Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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| Abstract: Nitrogen (N) leaching is caused by the mismanagement of water and fertilizer in greenhouse vegetable fields. Understanding N movement and leaching process is important for achieving high crop yields at low environmental costs. A field experiment was conducted for a greenhouse cucumber-tomato rotation system in the suburbs of Beijing, China. The DeNitrification-DeComposition (DNDC) model was used to quantitatively evaluate the soil N transport and leaching loss in the facility vegetable field after considering factors obtained from field experiments, such as soil temperature, humidity, and nitrate nitrogen (NO3--N) content. Conventional practices were selected as the baseline scenario, and the modeled scenarios, such as changes in soil properties, irrigation, and N application, were set according to the baseline. The results showed that the DNDC model can better simulate the vegetable yield, 5 cm soil temperature, 0–20 cm soil water-filled pore space, and NO3--N migration process, indicating that it is an effective tool for simulating and evaluating N transport and leaching in vegetable field soil. The modeling scenarios showed that the accumulation of NO3--N in the 0–60 cm soil was primarily affected by the irrigation amount and N application; soil pH and organic carbon were also important factors affecting NO3--N migration. Increasing irrigation amount significantly accelerated the downward movement of NO3--N, and increasing N application promoted the accumulation of NO3--N at the surface and a depth of 20 cm. Increasing soil pH lessened NO3--N surface accumulation; and to a certain extent, increasing soil organic carbon delayed the downward movement of NO3--NControlling water and fertilizer was the most effective method for mitigating N leaching. Compared with conventional measures, reducing irrigation and N application simultaneously by 20% significantly reduced NO3--N leaching by 59.04%. Changing irrigation method and increasing soil organic carbon content by 20% (to save water and fertilizer) further reduced NO3--N leaching by 69.04%. The DNDC model is a useful method for evaluating and controlling NO3--N leaching in vegetable fields. Changing management practices, such as N and water amounts as the soil quality improves, may be an effective way to reduce N leaching in vegetable fields. |
| Keyword: Facility vegetable field Nitrogen leaching Water and nitrogen control Soil organic carbon DNDC model |
