【作者】 熊金燕；

【导师】 章力干；

【作者基本信息】 安徽农业大学 ， 植物营养学， 2010， 硕士

【摘要】 巢湖水体污染已经进入富营养化阶段,造成生物多样性减少,经济损失和生态破坏严重。近年来随着我国环保事业的发展,流域内点源污染得到有效治理。但是湖泊水质并未得到有效的根本改善,其重要原因在于农业非点源污染,而降雨径流是农业非点源污染入湖的主要途径,在农村同时又存在不合理施肥等问题。因此掌握典型流域农田系统降雨径流相关资料对缓解和治理巢湖水体污染具有十分重要的意义。本课题对巢湖典型流域庐江同大镇农田系统中的水田和旱地地表径流的特点及其组成进行调查研究,通过现场实地监测和室内土柱淋洗实验,研究不同土地利用类型、不同降雨强度、不同施肥方式氮磷流失规律。研究结果表明:典型农田系统中,旱地氮磷流失量大于农田氮磷流失量,氮磷流失具备明显的季节特征,夏季和秋季是氮磷输出量的高峰期。其最高浓度达到旱地全氮8.233mg/l,全磷3.00mg/l,氨氮4.113mg/l;水田全氮浓度6.008 mg/l,全磷0.467mg/l,氨氮3.484mg/l。降雨过程中氮磷浓度变化幅度较大,可达5-6倍。水田和旱地土壤氮流失均以氨态氮为主,水田土壤流失比例平均在42.8%,旱地土壤流失比例平均在37.5%。氮磷累积流失量旱地土壤均高于水田土壤。随降雨的进行,氮磷浓度有所波动,整体呈下降趋势。且降雨初期氮磷浓度明显高于降雨结束时的浓度。室内土柱淋洗模拟实验结果与野外监测结果一致,均表现出旱地土壤淋洗中氮磷流失量高于水田土壤。不同施肥条件下,氮磷流失量占总施肥量的比例差异较大。在水田土壤淋洗中,习惯施肥条件下,氨氮流失比例范围在3.78-5.20%;全氮流失比例范围在4.70—8.31%;全磷流失比例范围在0.13-0.55%。配方施肥条件下,氨氮流失比例在1.82-5.77%;全氮流失比例范围在7.14-9.43%;全磷流失比例范围在0.44-0.56%。在旱地土壤淋洗中,习惯施肥条件下,氨氮流失比例范围在6.51-10.16%;全氮流失比例范围在7.14-9.43%;全磷流失比例范围在0.32-1.19%。配方施肥条件下,氨氮流失比例在6.63-7.66%;全氮流失比例范围在6.48-8.75%;全磷流失比例范围在1.20-3.18%。更多还原

【Abstract】 The serious eutrophication has appeared in Chaohu Lake because of water pollution and that has resulted in the reducing of biodiversity, the loss of economic and the destruction of ecological environment. This phenomenon was not considered to be the contribution of point source pollution in the industry due to effective control of waste drainage, but to be non-point source pollution in the agriculture, in which overland runoff of rainfall and irrational fertilization in agricultural planting played a main role in eutrophication of Chaohu Lake. Therefore, it is very important for mastering of relevant information about non-point source pollution in Chaohu Lake to release and control the water pollution in the Lake.In this work, the characteristics of overland runoff about the typical paddy field and arid land in Tongda Town, Lujiang County which belong to Chaohu Lake area, were investigated. The method of in-spot monitoring combined indoor soil-column leaching experiments was applied to study the rule of the loss of nitrogen-phosphorus fertilizer about the land-use types, the rainfall intensities and the fertilization way. The results showed that:In the typical agricultural system, the amount of nitrogen-phosphorus loss in arid field is higher than that of farmland, and it has obvious seasonal characteristics, which displayed that the peak output season of nitrogen-phosphorus is in summer and autumn. The great concentration for total nitrogen was gotten to 8.233 mg/l, for total phosphorus to 3.00 mg/l, and ammonia nitrogen to 4.113 mg/l in arid land, and the great concentration for total nitrogen was to 6.008 mg/l, total phosphorus to 0.467 mg/l, and ammonia nitrogen to 3.484 mg/l in paddy field.The ramp of nitrogen-phosphorus loss was varied to intensity of rainfall, sometime to 5-6 times. For nitrogen nutrient, the ammonia was the main loss form to both paddy field and arid land, and for the former, the loss rate to 42.8 %, and for the latter, to 37.5 %. The total amount of nitrogen-phosphorus loss for arid land was higher than that for paddy field. Although the concentration of nitrogen-phosphorus was fluctuated with rainfall, the overall level was tend to downward. And the concentration of nitrogen-phosphorus at the beginning of the rainfall was higher than that at the end.Laboratory soil column leaching experimental results were consistent with field monitoring, and it showed that the nitrogen-phosphorus leaching in arid land was beyond that in paddy field. Under different fertilizer, nitrogen and phosphorus fertilizer ratio of total were quite different. In the paddy field washing, the conventional fertilization conditions, the proportion of nitrogen loss was in the range of 3.78-5.20%, total N loss ranged of 4.70-8.31%, and total phosphorus loss of 0.13-0.55%. In the fertilization condition, the loss ratio was in the 1.82-5.77% for nitrogen, in the 0.13-0.55% for total N, and in 0.44-0.56% for total phosphorus. In arid land washing, the conventional fertilization conditions, the proportion of ammonia loss was ranged from 6.51 to 10.16%, total N loss ratio range of 7.14-9.43%, total phosphorus in the range of 0.32-1.19% loss ratio. Fertilization conditions, the loss ratio in the 6.63-7.66% nitrogen, total N loss ratio range of 6.48-8.75%, and total phosphorus in the range of 1.20-3.18% loss ratio.更多还原