CAJ | 학술논문

[目的]本文通过研究洱海北部地区不同轮作模式下农田氮、磷流失特征以期为环境污染风险评估和制定相关措施控制由农业造成的面源污染提供参考。[方法]试验中通过调查采自洱海北部地区7个乡镇4种不同种植模式下的水样及施肥情况分析了田面水和沟渠水的氮、磷含量动态变化情况,以及肥料的投入量与田面水和沟渠水中氮、磷浓度的关系。[结果]田面水中,不同轮作模式下氮素的流失差异显著,蚕豆-水稻比大蒜-水稻模式减少氮素流失风险38%。水溶态氮是氮流失的主要形态。可溶性氮浓度以大蒜-水稻模式最高。不同轮作模式下田面水中氮浓度基本趋势为：大蒜-水稻〉黑麦草-水稻〉蚕豆-水稻〉油菜-水稻。磷素流失总量偏低,且以泥沙结合态为主,不同轮作模式间各种形态的磷流失无显著差异。田面水中氮磷含量比沟渠水高,对总氮和总磷的增荷率分别为73%和82%。追肥是导致农田水对沟渠水增荷的关键因素。[结论]本研究中,大蒜-水稻是洱海流域农田氮磷流失风险最高的轮作模式。因此,应该综合考虑环境效益和经济效益,合理安排轮作模式。本研究为控制洱海流域农田面源污染和改善洱海水质提供了参考。
[목적]본문통과연구이해북부지구불동륜작모식하농전담、린류실특정이기위배경오염풍험평고화제정상관조시공제유농업조성적면원오염제공삼고。[방법]시험중통과조사채자이해북부지구7개향진4충불동충식모식하적수양급시비정황분석료전면수화구거수적담、린함량동태변화정황,이급비료적투입량여전면수화구거수중담、린농도적관계。[결과]전면수중,불동륜작모식하담소적류실차이현저,잠두-수도비대산-수도모식감소담소류실풍험38%。수용태담시담류실적주요형태。가용성담농도이대산-수도모식최고。불동륜작모식하전면수중담농도기본추세위：대산-수도〉흑맥초-수도〉잠두-수도〉유채-수도。린소류실총량편저,차이니사결합태위주,불동륜작모식간각충형태적린류실무현저차이。전면수중담린함량비구거수고,대총담화총린적증하솔분별위73%화82%。추비시도치농전수대구거수증하적관건인소。[결론]본연구중,대산-수도시이해류역농전담린류실풍험최고적륜작모식。인차,응해종합고필배경효익화경제효익,합리안배륜작모식。본연구위공제이해류역농전면원오염화개선이해수질제공료삼고。
[Objective] Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in the north of Erhai Lake basin were studied with the objective to provide references for risk evaluation of environmental pollution and formulating countermeasures to control the nonpoint source pollution from agriculture.[Method] Water samples collected in four typical crop rotation systems distributed in seven towns(townships) in the north of Erhai Lake basin were investigated,as well as the fertilizer input,to explore the dynamic change of nitrogen and phosphorus content in surface water of farmland and ditch water,and the correlation between fertilizer input and the concentrations of nitrogen and phosphorus in the surface water of farmland and in the ditch water.[Result] The results showed that nitrogen loss in surface water of farmland in different crop rotation systems differed greatly,and the risk of nitrogen loss was 38% lower in broad bean-rice crop rotation than that in garlic-rice crop rotation.The water soluble nitrogen was the primary form of nitrogen loss.The content of water soluble nitrogen was significantly higher in garlic-rice crop rotation than that in the other rotation systems,and the concentrations of nitrogen in the surface water of farmland in different crop rotation systems followed the sequence below:garlic-rice crop rotationryegrass-rice crop rotationbroad bean-rice crop rotationrape-rice crop rotation.The loss of phosphorus in the surface water of farmland was relatively low and phosphorus combined with silt was the primary form for phosphorus loss.There was no significant difference of the loss of various forms of phosphorus in different crop rotation systems.The contents of total nitrogen and total phosphorus in the surface water of farmland were higher than that in ditch water,with increasing rates of total nitrogen and total phosphorus in ditch water of 72% and 82%,respectively.Topdressing was the critical reason for the high concentrations of nitrogen and phosphorus in the surface water,which also caused the increasing load to the ditch water.[Conclusion] Both the nitrogen and phosphorus loss were the highest in garlic-rice crop rotation.Reasonable crop rotation systems should be established based on both the environmental and economic benefits.This study provided references for controlling the nonpoint source pollution of farmland and improving the water quality of Erhai Lake.