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Effect of Drainage Ditch Layout on nitrogen Loss by Runoff from an Agricultural Watershed

Pedosphere 2013年第2期23卷 256-264页

作者： ZHAnG Zhan-Yu KOnG Li-Li ZHU Lei R.M.MWIYA Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil-Water Environment in Southern China Ministry of EducationHohai University College of Water Conservancy and Hydropower Engineering Hohai University

A comparison experiment was performed, by designing one field ditch (D1 treatment), two field ditches (D2 treatment), three field ditches (D3 treatment), and no field ditch (CK treatment), in an upland of a small agricultural watershed in nanjing-Zhenjiang hilly regions to observe the farmland surface runoff and n loss characteristics under the different layouts of field ditch. As the layout density of field ditch increased, the drainage effect was improved, the timing of the runoff peak was advanced, and also the peak flow was augmented. At the same time, both the concentration and accumulated transfer flux of total nitrogen (Tn) were improved, and thereinto the accumulated transfer fluxes of Tn under D3, D2 and D1 treatments were increased by 1.46, 1.34 and 1.16 times, respectively, than that under CK treatment. However, the accumulated transfer fluxes of nitrate-nitrogen (no3-n) and ammonium-nitrogen (nH+4 -n) under D3, D2 and D1 treatments were reduced by 33.9%, 21.4% and 8.6%, and 35.8%, 24.7% and 12.2%, respectively, compared with those under CK treatment. Under CK treatment, the no3-n and nH+4-n concentrations were more sensitive to rainfall intensity than the Tn concentration. There were significant linear relationships between the transfer fluxes of Tn, no3 -n and nH+4 -n and the runoff flux, with the correlation coefficients of 0.942, 0.899 and 0.912, respectively. In addition, this correlation was also influenced by the layout density of field ditch. Therefore, the environmental effect should be taken into account when designing and constructing field ditches. Especially in the regions of severe fertilizer loss, the approaches of properly increasing the drainage area and decreasing the layout density of field ditch could be adopted under the precondition of avoiding crops from waterlogging.

关键词：径流流失排水沟渠小流域农业 no3-n nH4-n 氮素峰值时间

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Responses of Agronomic Benefit and Soil Quality to Better Management of nitrogen Fertilizer Application in Greenhouse Vegetable Land

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Pedosphere 2012年第5期22卷 650-660页

作者： JIAnG Hui-Min ZHAnG Jian-Feng SOnG Xiao-Zong LIU Zhao-Hui JIAnG Li-Hua YAnG Jun-Cheng Ministry of Agriculture Key Laboratory of Crop nutrition and Fertilization Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081(China) Institute of Agricultural Resources and Environment Shandong Academy of Agricultural SciencesJinan 250100(China)

As a result of intensive greenhouse vegetable production in northern China, the potential risk of nitrogen (n) fertilizer over-applied is increasingly apparent and is threatening ecosystem and the sustainability of food production. An experiment was carried out in Shouguang, Shangdong Province, China to evaluate agronomic benefit and soil quality under different n applications, including the conventional chemical n rate (1000 kg n ha-1 season-1, n1), 70% of n1 (n2), 70% of n1 + maize straw (n3), 50% of n1 + maize straw + drip irrigation (n4), and 0% of n1 (n0), during two successive growing seasons of autumn-winter (AW) and winter-spring (WS). The maximum yields for n4 were 1.1 and 1.0 times greater than those for n1 in the AW and WS seasons, respectively. n agronomic effciency (AEn) and apparent n recovery effciency (REn) were greatest with the n4. A significant relationship was found between soil nO-3 -n content and electrical conductivity (EC) (R2 = 0.61 in the AW season and R2 = 0.29 in the WS season). Reducing n fertilizer decreased soil nO-3 -n accumulation (20.9%-37.8% reduction in the AW season and 11.7%-20.1% reduction in the WS season) relative to the accumulation observed for n1 within the 0-100 cm soil layer. Soil urease and invertase activities were not significantly different among n treatments. The n4 treatment would be practical for reducing excess n input and maintaining the sustainability of greenhouse-based intensive vegetable systems in Shouguang.

关键词：氮肥施用量土壤质量农艺性状温室系统蔬菜地氮肥利用率 no3-n 生长季节

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Characteristics of nutrients in the Jiulong River and its impact on Xiamen Water, China

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Chinese Journal of Oceanology and Limnology 2013年第5期31卷 1055-1063页

作者：陈宝红暨卫东陈金民林彩黄海宁霍云龙纪贤标 Third Institute of Oceanography State Oceanic Administration College of Information Science and Technology Xiamen University

Water samples were collected at 20 sites on 4 occasions in 2009(twice in May,and once in both August and november) along the Jiulong River,South China to examine how nutrient inputs from the Jiulong River could affect the nutrient status of the Xiamen Water.Samples were analyzed for nitrite(nO2-n),nitrate(no3-n),ammonium(nH4-n),phosphate(PO4-P),silicate(SiO3-Si),salinity,and temperature,to determine the nutrient and trophic status of the river.The results indicate that nutrients are derived mainly from river runoff.no3-n was the main form of DIn in most parts of the river.In addition,no3-n,DIn,and SiO3-Si behave conservatively.There is a surplus of DIn and SiO3-Si in the river,and PO4-P is a limitation on phytoplankton growth.The concentration of DIn is typically above 0.60 mg/dm3,and higher than 1.00 mg/dm3in most parts of the river.The concentration of PO4-P is typically above 0.02 mg/dm3,while the concentration of SiO3-Si is higher than 1.00 mg/dm3.Between 2003 and 2008,samples were collected 3 times per year(May,August and november) at 27 sites in the Xiamen Water and analyzed for nO2-n,no3-n,nH4-n,PO4-P,salinity,and temperature.We discovered that the Jiulong River was the key source of DIn into the Xiamen Water,but not PO4-P,indicating the reason of the n/P molar ratio imbalance in the Xiamen Water.In the future,the effects of high DIn concentrations on the phytoplankton communities and marine ecosystems of the Xiamen Water shall be studied.

关键词：营养特性九龙江水样厦门中国 no3-n nH4-n 浮游植物生长

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Potato-Cabbage Double Cropping Effect on nitrate Leaching and Resource-Use Efficiencies in an Irrigated Area

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Pedosphere 2012年第6期22卷 842-847页

作者： HU Bo FAn Ming-Shou HAO Yun-Feng ZHAnG Jian-Hua College of Agronomy Inner Mongolia Agricultural UniversityHohhot 010019(China) Bayannur City Agriculture Science Institute Bayannur 015500(China) School of Life Sciences and State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongHong Kong(China)

To reduce the nitrate leaching risk after potato (Solanum tuberosum L.) harvest and improve nitrogen fertilizer-use efficiency, a potato-cabbage double cropping system (DCS) was established at Hetao, north China, an arid area with irrigated land. A two-year field experiment demonstrated that planting early-maturing potato cultivar under plastic mulch shortened its growth period by 14 d and allowed a second crop of cabbage to scavenge the soil residual nO 3 -n to a depth of 160 cm, substantially reducing the risk of nitrate leaching into groundwater. The yearly total n uptake in DCS was about 110 kg ha 1 more than that in the conventional cropping system (CCS), i.e., mono potato planting. This accounted for apparent nitrogen recovery (AnR) improvement of 16.90%- 26.57% in the DCS as compared to that in the CCS for both years. As a result, the soil residual nO 3 -n in the 0-160 cm soil profile in the DCS was lower than that in the CCS. The solar energy-use efficiency and soil-use efficiency were also substantially increased with DCS.

关键词：资源利用效率硝态氮淋失土壤残留灌溉面积圆白菜土豆早熟马铃薯 no3-n

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Achieving low effluent nO_3-n and Tn concentrations in low influent chemical oxygen demand(COD) to total Kjeldahl nitrogen(TKn) ratio without using external carbon source

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Chinese Journal of Oceanology and Limnology 2015年第4期33卷 1039-1052页

作者：操家顺 OLEYIBLO Oloche James 薛朝霞 OTACHE Y.Martins 冯骞 Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education College of Environment Hohai University College of Environment Hohai University national Engineering Research Center of Water Resource Efficient Utilization and Engineering Safety Hohai University Department of Agricultural & Bioresources Engineering Federal University of Technology

Two mathematical models were used to optimize the performance of a full-scale biological nutrient removal(BnR) activated treatment plant, a plug-flow bioreactors operated in a 3-stage phoredox process configuration, anaerobic anoxic oxic(A2 /O). The ASM2 d implemented on the platform of WEST2011 software and the Bio Win activated sludge/anaerobic digestion(AS/AD) models were used in this study with the aim of consistently achieving the designed effluent criteria at a low operational cost. Four ASM2 d parameters(the reduction factor for denitrification(η no3, H), the maximum growth rate of heterotrophs( μ H), the rate constant for stored polyphosphates in PAOs(q pp), and the hydrolysis rate constant(k h)) were adjusted. Whereas three Bio Win parameters(aerobic decay rate(b H), heterotrophic dissolved oxygen(DO) half saturation(K OA), and Y P /acetic) were adjusted. Calibration of the two models was successful; both models have average relative deviations(ARD) less than 10% for all the output variables. Low effluent concentrations of nitrate nitrogen(n-no3), total nitrogen(Tn), and total phosphorus(TP) were achieved in a full-scale BnR treatment plant having low influent chemical oxygen demand(COD) to total Kjeldahl nitrogen(TKn) ratio(COD/TKn). The effluent total nitrogen and nitrate nitrogen concentrations were improved by 50% and energy consumption was reduced by approximately 25%, which was accomplished by converting the two-pass aerobic compartment of the plug-flow bioreactor to anoxic reactors and being operated in an alternating mode. Findings in this work are helpful in improving the operation of wastewater treatment plant while eliminating the cost of external carbon source and reducing energy consumption.

关键词：化学需氧量外加碳源 COD 水浓度凯氏氮 no3-n 进水 Tn

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The release behavior of inorganic nitrogen and phosphorus in sediment during disturbance

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Chinese Journal of Oceanology and Limnology 2008年第2期26卷 197-202页

作者：王丕波宋金明郭占勇李鹏程 north China Sea Branch of the State Oceanic Administration Institute of Oceanology The Chinese Academy of Sciences

Sediments and surface water were sampled in a tide flat in the Huiquan Bay, Qingdao, China in January 2004 to simulate the exchange of nH4-n/no3-n/ PO 43- between sediments and surface water. A working system was designed with which samples were shaken at 60, 120 and 150 revolutions per minute (r/min). Experiment results show that nH4-n concentration in water at shaking rate of 60r/min decreased gradually, while at 120r/min increased gradually. In resuspension, fine-grained sediments contributed most nH4-n to the seawater, followed by medium-grained and coarse-grained sediments. The no3-n concentration in water had a negative relation with the shaking rate; the medium-grained sediments contributed more no3-n to seawater than the coarse-and fine-grained sediments. The PO 43- concentration is positively related with the shaking rate, the fine-grained sediments were the main n and P contributor to the seawater, followed by medium-and coarse-grained sediments.

关键词：再悬浮沉淀物 nH4-n no3-n

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Soil Carbon and nitrogen in Response to Perennial Bioenergy Grass, Cover Crop and nitrogen Fertilization

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Pedosphere 2017年第2期27卷 223-235页

作者： Upendra M. SAInJU Hari P. SInGH Bharat P. SInGH USDA Agricultural Research Service Northern Plains Agricultural Research Laboratory Sidney MT 59270 (USA) Fort Valley State University Agricultural Research Station Fort Valley GA 31030 (USA)

Cover crop and nitrogen(n) fertilization may maintain soil organic matter under bioenergy perennial grass where removal of aboveground biomass for feedstock to produce cellulosic ethanol can reduce soil quality. We evaluated the effects of cover crops and n fertilization rates on soil organic carbon(C)(SOC), total n(STn), ammonium n(nH_4-n), and nitrate n(nO_3-n) contents at the0–5, 5–15, and 15–30 cm depths under perennial bioenergy grass from 2010 to 2014 in the southeastern USA. Treatments included unbalanced combinations of perennial bioenergy grass, energy cane(Saccharum spontaneum L.) or elephant grass(Pennisetum purpureum Schumach.), cover crop, crimson clover(Trifolium incarnatum L.), and n fertilization rates(0, 100, and 200 kg n ha^(-1)). Cover crop biomass and C and n contents were greater in the treatment of energy cane with cover crop and 100 kg n ha^(-1) than in the treatment of energy cane and elephant grass. The SOC and STn contents at 0–5 and 5–15 cm were 9%–20% greater in the treatments of elephant grass with cover crop and with or without 100 kg n ha^(-1)than in most of the other treatments. The soil nO_3-n content at 0–5 cm was 31%–45% greater in the treatment of energy cane with cover crop and 100 kg n ha^(-1)than in most of the other treatments.The SOC sequestration increased from 0.1 to 1.0 Mg C ha^(-1)year^(-1)and the STn sequestration from 0.03 to 0.11 Mg n ha^(-1)year^(-1)from 2010 to 2014 for various treatments and depths. In contrast, the soil nH_4-n and nO_3-n contents varied among treatments,depths, and years. Soil C and n storages can be enriched and residual nO_3-n content can be reduced by using elephant grass with cover crop and with or without n fertilization at a moderate rate.

关键词：多年生禾草覆盖作物生物能源土壤碳氮肥硝态氮含量地上生物量 no3-n

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Evaluating the Validity of a nitrate Quick Test in Different Chinese Soils

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Pedosphere 2012年第5期22卷 623-630页

作者： YUE Xian-Lu LI Fei HU Yun-Cai ZHAnG Huai-Zhi JI Hong-Jie ZHAnG Wei-Li U. SCHMIDHALTER Chair of Plant nutrition Technische Univcrsitiit Miinchen Emil-Ramann-Str. 2 Freising D-85350 (Germany) Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 (China)

Because laboratory tests are expensive and time-consuming and may not be available to farmers, soil nitrate quick tests are required for optimal nitrogen management strategies in China to increase nitrogen use effciency and to reduce nitrogen losses. A total of 328 soil samples were collected at different soil depths from 225 sites in China, which covered a wide range of climatic and geographic regions, soil types, croplands and soil textures, to evaluate the suitability of a quick reflectometer test method for analysing soil nO-3-n in a wide range of soil nO-3 concentrations, soil types and cropping systems in China, mainly by comparison of soil nO-3-n assessed by a quick-test method (a reflectometer) and a standard laboratory method, i.e., high-performance liquid chromatography (HPLC). The reflectometer showed excellent agreement with the laboratory HPLC method with regard to soil nitrate contents for all analysed soil samples. The linear regression had slopes of 1 ± 0.08 and intercepts of ±1.38 mg nO-3-n L-1 among different soil types and croplands. Compared with the 1:1 lines, the regression analysis for each soil type showed statistically significant but small differences in slope; the relative difference between the values measured using the two analytical systems varied from -8% to 6%, and there were no differences in intercept except for paddy soil. The reflectometer showed adequate, statistically significant precision in determining soil nitrate contents, and it could therefore be directly used instead of the laboratory methods for soil nO-3-n measurement in China.

关键词：土壤硝酸盐快速测试中国评估 no3-n 高效液相色谱法硝酸盐含量土壤类型

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nutrient and eutrophication characteristics of the Dongshan Bay, South China

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Chinese Journal of Oceanology and Limnology 2014年第4期32卷 886-898页

作者：陈宝红暨卫东周开文贺青傅婷婷 Third Institute of Oceanography State Oceanic Administration

We recorded nO 3-n, nO 2-n, nH 4-n, PO 4-P, SiO 3-Si, salinity, and temperature data at 10 stations in the Dongshan Bay in May, June, July, August, October, and november 2008, analyzing nutrient and eutrophication characteristics. The mean concentration of dissolved inorganic nitrogen(DIn) was 0.30–0.40 mg/dm 3; generally, nO 3-n was the main form in most areas. The mean concentrations of PO 4-P and SiO 3-Si were 0.040–0.060 mg/dm 3 and 1.00–1.50 mg/dm 3, respectively. We proved that the majority of the SiO 3-Si in the Dongshan Bay came from the Zhangjiang River, with some coming from the Bachimen Strait. DIn originated from both the Zhangjiang River and the Bachimen Strait. Most PO 4-P originated from the Bachimen Strait, and some came from the Zhangjiang River. We found that P was an overall limiting factor to the phytoplankton community in most of the Dongshan Bay, and that Si and n were in surplus. However, near the Bachimen Strait Si became a limiting factor, especially for diatoms, while P and n were in comparative surplus. We used a potential eutrophication assessment method to analyze eutrophication, and showed that the most serious eutrophication occurred near the Zhangjiang River estuary and near the Bachimen Strait. In 2008, DIn levels were four times higher than that in 1988; PO 4-P levels were threefold higher, while SiO 3-Si was approximately double. Dissolved nutrients increased between 1988 and 2008. DIn increased at the greatest rate comparing to PO 4-P and SiO 3-Si, thus the n/P and n/Si mol ratios increased. Further studies on the effects of high DIn concentrations on the phytoplankton communities and marine ecosystems of the Dongshan Bay are needed.

关键词：水体富营养化东山湾特征浮游植物群落 no3-n 中国平均浓度海洋生态系统

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不同施氮水平对深层包气带土壤氮素淋溶累积的影响

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农业工程学报 2012年第7期28卷 103-110页

作者：商放泽杨培岭李云开任树梅刘培斌贺国平中国农业大学水利与土木工程学院北京100083 北京市水利规划设计研究院北京100048

为研究深层包气带土壤中氮素的迁移规律,采用田间小区试验,研究了不同施氮水平(142.5、285和427.5kg/hm2)对夏玉米种植期间0～500cm包气带土壤中氮素淋溶累积的影响。结果表明,不同施氮水平对no3--n、nH4+-n和总氮有显著影响,施氮越多,n... 详细信息

为研究深层包气带土壤中氮素的迁移规律,采用田间小区试验,研究了不同施氮水平(142.5、285和427.5kg/hm2)对夏玉米种植期间0～500cm包气带土壤中氮素淋溶累积的影响。结果表明,不同施氮水平对no3--n、nH4+-n和总氮有显著影响,施氮越多,no3--n、nH4+-n和总氮在土壤中的淋溶累积也就越多,夏玉米生育期间土壤中氮素的淋溶累积含量随着夏玉米生长逐渐减少。在0～200cm土层中,收获后不同施肥水平土壤中no3--n和总氮累积量随施氮量增加而增多,285kg/hm2施氮水平nH4+-n累积量最多,427.5kg/hm2施氮水平nH4+-n累积量最少,但相差不超过0.1kg/hm2,收获后土壤中氮素累积量有损失。夏玉米生育期间不同施氮水平对土壤no3--n、nH4+-n和总氮的影响深度主要为0～145cm。粉砂壤土中氮素更易累积,砂质壤土中氮素较易随水分淋溶至下层。142.5kg/hm2施氮水平可有效减少no3--n在土壤中的淋溶损失,降低土壤中nH4+-n和总氮的含量,对地下水构成的潜在污染风险最小。北京地区地下水埋深较深,no3--n不易淋溶至地下水,但长期大量施用氮肥、田间土壤大孔隙的存在等会加速no3--n向深层土壤迁移,对地下水水质构成威胁。

关键词：淋溶氮土壤累积 no3-n nH4+-n

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