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Straw mulching alters the composition and loss of dissolved organic matter in farmland surface runoff by inhibiting the fragmentation of soil small macroaggregates
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作者 Shanshan Cai Lei Sun +7 位作者 Wei Wang Yan Li Jianli Ding Liang Jin Yumei Li Jiuming Zhang Jingkuan Wang Dan Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1703-1717,共15页
Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How st... Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland. 展开更多
关键词 dissolved organic matter black soil surface runoff AGGREGATES fluorescence spectrum
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An Evaluation of Manure Management Strategies, Phosphorus Surface Runoff Potential and Water Usage at an Arkansas Discovery Dairy Farm
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作者 James M. Burke Mike B. Daniels +5 位作者 Pearl Webb Andrew N. Sharpley Timothy Glover Lawrence Berry Karl W. Van Devender Stan Rose 《Journal of Environmental Protection》 2023年第9期742-760,共19页
Manure management is an essential component of dairy production. Nutrient-laden, field-applied dairy manure often serves as a fertilizer source, but can also pose environmental threats if not properly managed. The Haa... Manure management is an essential component of dairy production. Nutrient-laden, field-applied dairy manure often serves as a fertilizer source, but can also pose environmental threats if not properly managed. The Haak dairy farm, located in Decatur, Arkansas, was granted a permit by the Arkansas Department of Environmental Quality (ADEQ) to employ a unique method in treating and storing cattle manure generated during the milking process. This method includes minimizing water use in wash water, dry scraping solids to combine with sawdust for composting and pumping effluent underground into a sloped concrete basin that serves as secondary solid separator before transporting the manure effluent into an interception trench and an adjacent grassed field to facilitate manure nutrient uptake and retention. The Arkansas Discovery Farm program (ADF) is conducting research to evaluate the environmental performance of the dairy’s milk center wash water treatment system (MCWW) by statistical analysis, characterization of phosphorus (P) migration in soil downslope from the inception trench, temperature measurements, and nutrient analysis of a stored dry stack manure/sawdust mixture. Goals included determining possible composting effectiveness along with comparisons to untreated dairy manure and quantifying the use of on-farm water. Results from this research demonstrated that: 1) The MCWW was effective at retaining manure-derived nutrients and reducing field nutrient migration as the MCWW interception trench had significantly higher total nitrogen (TN) (804.2 to 4.1), total phosphorus (TP) (135.6 to 1.5), and water extractable phosphorus (WEP) (55.0 to 1.0) concentrations in milligrams per liter (mg⋅L<sup>-1</sup>) than the downhill freshwater pond respectively;2) temperature readings of the manure dry stack indicated heightened levels of microbial and thermal activity, but did not reach a standard composting temperature of 54°C;3) manure dry stack nutrient content was typically higher than untreated dairy manure when measured on a “dry basis” in ppm, but was lower on an “as is basis” in ppm and kg/metric ton;and 4) water meter readings showed that the greatest use of on-farm water was for farm-wide cattle drinking (18.77), followed by water used in the milking center (3.45) and then followed by human usage (0.02) measured in cubic meters per day (m<sup>3</sup>⋅d<sup>-1</sup>). These results demonstrate that practical innovations in agricultural engineering and environmental science, such as the Haak dairy’s manure treatment system, can effectively reduce environmental hazards that accompany the management of manure at this dairy operation. 展开更多
关键词 Manure Management Soil Test Phosphorus surface runoff Water Usage Manure Composting Environmental Hazards ARKANSAS Milk Center Wastewater Treatment System Statistical Analysis
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Influence of Vegetation Coverage on Surface Runoff and Soil Moisture in Rainy Season in Dry-hot Valley 被引量:7
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作者 郭芬芬 南岭 +1 位作者 陈安强 刘刚才 《Agricultural Science & Technology》 CAS 2010年第4期138-143,共6页
[Objective]The research aimed to study the effects of vegetation coverage on the changes of soil moisture in rainy season in dry-hot valley.[Method]The surface runoff and soil moisture of slope with vegetation coverag... [Objective]The research aimed to study the effects of vegetation coverage on the changes of soil moisture in rainy season in dry-hot valley.[Method]The surface runoff and soil moisture of slope with vegetation coverage and bare land in rainy reason in Jinsha River at Yuanmou County of Yunnan Province were observed continuously.Moreover,the statistical analysis was made based on the observation data.[Result]The vegetation coverage could decrease surface runoff and the surface runoff on bare land(CK) was 22 times as the plot with vegetation coverage.The soil water content in 0-180 cm layer with vegetation coverage increased by 37.8% than bare land.The stability of soil moisture content in deep layer was enhanced and the physical properties stability of soil was maintained.The soil moisture content in different depth of soil had significant difference and the changes of soil moisture content were obviously different.[Conclusion]The vegetation coverage of slope could change the soil hydrology obviously and keep soil moisture at the higher level,especially at soil layer below 20 cm. 展开更多
关键词 Vegetation coverage surface runoff Soil moisture Dry-hot valley
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Applications of a Surface Runoff Model with Horton and Dunne Runoff for VIC 被引量:18
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作者 谢正辉 苏凤阁 +3 位作者 曾庆存 郭裕福 梁旭 郝振纯 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第2期165-172,共8页
Surface runoff is mainly generated by two mechanisms, infiltration excess (Horton) runoff and saturation excess (Dunne) runoff; and the spatial variability of soil properties, antecedent soil moisture, topography, and... Surface runoff is mainly generated by two mechanisms, infiltration excess (Horton) runoff and saturation excess (Dunne) runoff; and the spatial variability of soil properties, antecedent soil moisture, topography, and rainfall will result in different surface runoff generation mechanisms. For a large area (e.g., a model grid size of a regional climate model or a general circulation model), these runoff generation mechanisms are commonly present at different portions of a grid cell simultaneously. Missing one of the two major runoff generation mechanisms and failing to consider spatial soil variability can result in significant under/over estimation of surface runoff which can directly introduce large errors in soil moisture states over each model grid cell. Therefore, proper modeling of surface runoff is essential to a reasonable representation of feedbacks in a land-atmosphere system. This paper presents a new surface runoff parameterization with the Philip infiltration formulation that dynamically represents both the Horton and Dunne runoff generation mechanisms within a model grid cell. The parameterization takes into account the effects of soil heterogeneity on Horton and Dunne runoff. The new parameterization is implemented into the current version of the hydrologically based Variable Infiltration Capacity (VIC) land surface model and tested over one watershed in Pennsylvania, USA and over the Shiguanhe Basin in the Huaihe Watershed in China. Results show that the new parameterization plays a very important role in partitioning the water budget between surface runoff and soil moisture in the atmosphere-land coupling system, and has potential applications on large hydrological simulations and land-atmospheric interactions. It is further found that the Horton runoff mechanism should be considered within the context of subgrid-scale spatial variability of soil properties and precipitation. 展开更多
关键词 Horton runoff Dunne runoff subgrid-scale spatial variability soil heterogeneity land surface model hydrologic model soil moisture
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Pollutant loads of surface runoff in Wuhan City Zoo, an urban tourist area 被引量:23
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作者 ZHAO Jian-wei SHAN Bao-qing YIN Cheng-qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第4期464-468,共5页
The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one ro... The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one road, were selected for sampling and study. The results indicate that pollutants ranked in a predictable order of decreasing load (e.g. animal yard〉roof〉woodland〉road), with animal yards acting as the key pollution source in the zoo. Pollutants were transported mainly by particulate form in runoff. Particulate nitrogen and particulate phosphorous accounted on average for 61%, 78% of total pollutant, respectively, over 13 monitored rainfall events. These results indicate the treatment practices should be implemented to improve particulate nutrient removal. Analysis of the M(V) curve indicate that no first flush effect existed in the surface runoff from pervious areas (e.g. woodland, animal ground yard), whereas a first flush effect was evident in runoff from impervious surfaces (e.g. animal cement yard, roof, road). 展开更多
关键词 surface runoff stormwater pollution urban tourist area impervious/pervious surface M(V) curve
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Characterization of surface runoff from a subtropics urban catchment 被引量:10
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作者 HUANG Jin-liang DU Peng-fei +4 位作者 AO Chi-tan LEI Mui-heong ZHAO Dong-quan HO Man-him WANG Zhi-shi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第2期148-152,共5页
Characteristics of surface runoff from a 0.14-km^2 urban catchment with separated sewer in Macao was investigated. Water quality measurements of surface runoff were carried out on five rainfall events during the perio... Characteristics of surface runoff from a 0.14-km^2 urban catchment with separated sewer in Macao was investigated. Water quality measurements of surface runoff were carried out on five rainfall events during the period of August to November, 2005. Water quality parameters such as pH, turbidity, TSS, COD, TN, Zn, Pb, and Cu were analyzed. The results show that TN and COD are the major pollutants from surface runoff with mean concentration of 8.5 and 201.4 mg/L, both over 4-fold higher compared to the Class V surface water quality standard developed by China SEPA. Event mean concentration (EMC) for major pollutants showed considerable variations between rainfall events. The largest rainfall event with the longest length of antecedent dry weather period (ADWP) produced the highest EMC of TN, TSS and COD. From the pollutographs analysis, the peak concentration of TN precedes the peak runoff flow rate for all three rainfall events. The tendency of the concentration of TSS, turbidity and COD changing with runoff flow varies between rainfall events. The relationship between TSS and other parameters were analyzed to evaluate the efficiency of the physical treatment process to control the surface runoff in the urban catchment. Based on the correlation of parameters with TSS, high treatment efficiency of TSS, TN and COD was expected. The most significant event in term of first flush is the one with the strongest rainfall intensity and longest length of ADWP. TN always showed first flush phenomenon in all three rainfall events, which suggested that the surface runoff in the early stage of surface runoff should be dealt with for controlling TN losses during rainfall events. 展开更多
关键词 surface runoff event mean concentration (EMC) first flush MACAO
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Surface runoff processes and sustainable utilization of water resources in Manas River Basin, Xinjiang, China 被引量:18
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作者 HongBo LING HaiLiang XU +1 位作者 JinYi FU XinHua LIU 《Journal of Arid Land》 SCIE 2012年第3期271-280,共10页
Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and ... Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and periods of runoff based on the runoff and climate data for the past 50 years. Subsequently, with the socioeconomic and water resources data, we studied a comprehensive evaluation on the water security in this area. The results indicated that the stream flows in the three hydrological stations of Hongshanzui, Kensiwat and Bajiahu have sig- nificantly increased and undergone abrupt changes, with periods of 18 and 20 years. According to assessment, water security in the Manas River Basin was at an unsafe level in 2008. In criterion layer, the ecological security index and the index of supply-demand situation are both at the relatively secure level; the quantity index and so- cioeconomic index of water resources are at the unsafe level and basic security level, respectively. Therefore, in order to achieve sustainable economic and social development within the Manas River Basin, it is vital to take a series of effective measures to improve the status of water security. 展开更多
关键词 surface runoff processes period and trend sustainable utilization water resources the Manas River Basin fuzzycomprehensive evaluation
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Synthesis and application of lignin-based copolymer LSAA on controlling non-point source pollution resulted from surface runoff 被引量:8
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作者 LIU Chen WU Guangxia MU Huanzhen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期820-826,共7页
In this article,alkali lignin separated from paper pulp waste was grafted into a novel copolymer LSAA (a copolymer of lignin,starch, acrylamide,and acrylic acid).Its practical application effect and environmental safe... In this article,alkali lignin separated from paper pulp waste was grafted into a novel copolymer LSAA (a copolymer of lignin,starch, acrylamide,and acrylic acid).Its practical application effect and environmental safety were studied.The results of field simulation experiment indicated that the application of LSAA significantly affected the output of the runoff and pollutants.The runoff quantity was decreased by 16.67%-47.00%and the loads of total suspended solids (TSS),chemical oxygen demand (COD),total nit... 展开更多
关键词 application COPOLYMER a copolymer of lignin STARCH acrylamide and acrylic acid (LSAA) non-point source pollution (NPS) surface runoff
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Implementation of a Surface Runoff Model with Horton and Dunne Mechanisms into the Regional Climate Model RegCM_NCC 被引量:3
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作者 史学丽 谢正辉 +1 位作者 刘一鸣 杨宏伟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第5期750-764,共15页
A surface runoff parameterization scheme that dynamically represents both Horton and Dunne runoff generation mechanisms within a model grid cell together with a consideration of the subgrid-scaie soil heterogeneity, i... A surface runoff parameterization scheme that dynamically represents both Horton and Dunne runoff generation mechanisms within a model grid cell together with a consideration of the subgrid-scaie soil heterogeneity, is implemented into the National Climate Center regional climate model (RegCM_NCC). The effects of the modified surface runoff scheme on RegCMANCC performance are tested with an abnormal heavy rainfall process which occurred in summer 1998. Simulated results show that the model with the original surface runoff scheme (noted as CTL) basically captures the spatial pattern of precipitation, circulation and land surface variables, but generally overestimates rainfall compared to observations. The model with the new surface runoff scheme (noted as NRM) reasonably reproduces the distribution pattern of various variables and effectively diminishes the excessive precipitation in the CTL. The processes involved in the improvement of NRM-simulated rainfall may be as follows: with the new surface runoff scheme, simulated surface runoff is larger, soil moisture and evaporation (latent heat flux) are decreased, the available water into the atmosphere is decreased; correspondingly, the atmosphere is drier and rainfall is decreased through various processes. Therefore, the implementation of the new runoff scheme into the RegCMANCC has a significant effect on results at not only the land surface, but also the overlying atmosphere. 展开更多
关键词 surface runoff regional climate model PRECIPITATION water vapor
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Analysis on the Pollution Characteristics of Surface Runoff in Zhenjiang City 被引量:5
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作者 WAN You-ling,ZHANG Bo,WU Chun-du School of Environment,Jiangsu University,Zhenjiang 212013,China 《Meteorological and Environmental Research》 CAS 2011年第5期76-78,共3页
[Objective] The aim was to analyze the pollution characteristics of surface runoff in Zhenjiang City.[Method] On July 4 and August 16,2010,surface runoff samples were collected in different rainfall durations in Zhenj... [Objective] The aim was to analyze the pollution characteristics of surface runoff in Zhenjiang City.[Method] On July 4 and August 16,2010,surface runoff samples were collected in different rainfall durations in Zhenjiang City,and the variation characteristics of suspended substance (SS),chemical oxygen demand (CODCr),ammonia nitrogen (NH3-N) and total phosphorus (TP) in surface runoff were analyzed.[Result] With the increase of rainfall duration,SS concentration in surface runoff of Zhenjiang City on July 4 and August 16,2010 went up firstly and then went down,with the maximum concentration of 1 240 and 160mg/L,respectively,and the decreasing rang of SS concentration in the late stage of rainfall on July 4 was obviously greater than that of August 16 due to stronger rainfall on July 4.The general variation of CODCr was similar to that of SS concentration,and the change range of CODCr on July 4 (32-212mg/L) was larger than that of August 16 (13-53mg/L).In addition,the variation trends of NH3-N and TP concentration were similar,namely they increased firstly and then reduced rapidly,and the decreasing range of NH3-N and TP concentration was greater than that of SS concentration in the late stage of rainfall.[Conclusion] The research results could provide references for the study on water quality variation characteristics and treatment of surface runoff. 展开更多
关键词 surface runoff Pollution characteristic Zhenjiang China
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Transport of phosphorus in runoff and sediment with surface runoff from bare purple soil during indoor simulated rainfall 被引量:3
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作者 MA Xiao YANG Jie +3 位作者 ZHOU Xiang-jun WU Hong-tao XIONG Qiao LI Ye 《Journal of Mountain Science》 SCIE CSCD 2022年第8期2333-2345,共13页
Phosphorus(P)in surface runoff from purple soil is a critical element of agricultural nonpoint source pollution,leading to eutrophication of surface waters in the Three Gorges Reservoir Area(TGRA)of China.This work ai... Phosphorus(P)in surface runoff from purple soil is a critical element of agricultural nonpoint source pollution,leading to eutrophication of surface waters in the Three Gorges Reservoir Area(TGRA)of China.This work aimed to understand the processes and mechanisms of P losses from bare purple soil.Based on an indoor rainfall simulation experiment,we focused on the processes of surface runoff and P losses via different hydrological pathways.Experimental treatments included three simulated rainfall intensities,four slope gradients,and three fertilizer treatments.P loss from sediment was the main pathway in the purple soil,and bioavailable P was mainly transferred in dissolved P(DP)of runoff water.The P loss loads tend to grow with the increase of the slope until 25°for the maximum load of runoff water and 20°for the maximum load of sediment.Concentrations of DP in the surface runoff after fertilizer application can exceed the estimates of those required for accelerated eutrophication.Sediment P control might be an essential way for reducing P loss in purple soil for the local government and farmers of TGRA. 展开更多
关键词 surface runoff Sediment yield Phosphorus loss Purple soil Simulated rainfall
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Phosphorus losses via surface runoff in rice-wheat cropping systems as impacted by rainfall regimes and fertilizer applications 被引量:8
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作者 LIU Jian ZUO Qiang +6 位作者 ZHAI Li-mei LUO Chun-yan LIU Hong-bin WANG Hong-yuan LIU Shen ZOU Guo-yuan REN Tian-zhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第3期667-677,共11页
Phosphorus(P) losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice(O... Phosphorus(P) losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice(Oryza sativa L.) and wheat(Triticum aestivum L.) cropping systems in Lake Taihu region, China. The study was conducted on two types of paddy soils(Hydromorphic at Anzhen site, Wuxi City, and Degleyed at Xinzhuang site, Changshu City, Jiangsu Province) with different P status, and it covered 3 years with low, high and normal rainfall regimes. Four rates of mineral P fertilizer, i.e., no P(control), 30 kg P ha^(–1) for rice and 20 kg P ha^(–1) for wheat(P_(30+20)), 75 plus 40(P_(75+40)), and 150 plus 80(P_(150+80)), were applied as treatments. Runoff water from individual plots and runoff events was recorded and analyzed for total P and dissolved reactive P concentrations. Losses of total P and dissolved reactive P significantly increased with rainfall depth and P rates(P〈0.0001). Annual total P losses ranged from 0.36–0.92 kg ha^–1 in control to 1.13–4.67 kg ha^–1 in P150+80 at Anzhen, and correspondingly from 0.36–0.48 kg h^–1 to 1.26–1.88 kg ha^–1 at Xinzhuang, with 16–49% of total P as dissolved reactive P. In particular, large amounts of P were lost during heavy rainfall events that occurred shortly after P applications at Anzhen. On average of all P treatments, rice growing season constituted 37–86% of annual total P loss at Anzhen and 28–44% of that at Xinzhuang. In both crop seasons, P concentrations peaked in the first runoff events and decreased with time. During rice growing season, runoff P concentrations positively correlated(P〈0.0001) with P concentrations in field ponding water that was intentionally enclosed by construction of field bund. The relative high P loss during wheat growing season at Xinzhuang was due to high soil P status. In conclusion, P should be applied at rates balancing crop removal(20–30 kg P ha^–1 in this study) and at time excluding heavy rains. Moreover, irrigation and drainage water should be appropriately managed to reduce runoff P losses from rice-wheat cropping systems. 展开更多
关键词 double cropping system intensive agriculture Lake Taihu region phosphorus loss surface runoff water quality
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Study on Management and Control of Nonpoint Source Pollution from Urban Surface Runoff 被引量:2
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作者 Chen Keliang Zhu Xiaodong Wang Xianghua Ma Yan 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第1期39-44,共6页
Urbanization is the dominant form of land-use change in terms of impacts on water quality, hydrology, physical proper- ties of watersheds and their nonpoint source (NPS) pollution po- tential at present. Urbanization ... Urbanization is the dominant form of land-use change in terms of impacts on water quality, hydrology, physical proper- ties of watersheds and their nonpoint source (NPS) pollution po- tential at present. Urbanization has changed the source, process and sink of urban NPS pollution, especially raised the pollution load of urban runoff NPS in receiving water. Urban runoff pollu- tion is a hot spot of research on NPS. This paper analyzed type, source and harm of the NPS pollutants of urban runoff and its influence on the receiving water. Through estimating NPS pollu- tion load of urban runoff and summarizing the law and character- istics of urban runoff NPS systemically, study on management and control of urban runoff NPS pollution was focused on the applica- tion of BMPs (best management practices). It is a fresh method- ology that management and control on NPS pollution from urban surface runoff was analyzed by methods of landscape ecology, environmental economics and environmental management. The paper provided a scientific reference for mitigating urban water environment pressure and an effective method for management and control of NPS pollution from urban surface runoff.. 展开更多
关键词 urban surface runoff nonpoint source pollution MANAGEMENT CONTROL
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Impact of Land Use and Land Cover Changes on Surface Runoff and Sediment Yield in the Little Ruaha River Catchment 被引量:3
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作者 Nyemo A. Chilagane Japhet J. Kashaigili +4 位作者 Edmund Mutayoba Paul Lyimo Pantaleo Munishi Christine Tam Neil Burgess 《Open Journal of Modern Hydrology》 2021年第3期54-74,共21页
Little Ruaha River catchment (6370 Km<sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">) in the Southern Agricultural</span&g... Little Ruaha River catchment (6370 Km<sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">) in the Southern Agricultural</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> Growth Corridor of Tanzania (SAGCOT), is one of the country’s most significant waterways due to its ecological composition and economic value. Regardless of its ecological and economical value, the regional hydrologic condition has been tremendously affected due to land uses alteration, influenced by different socio-economic factors. This study aimed to understand the associated impacts of the present Land Use Land Cover (LULC) change on the surface runoff and sediment yield in the Little Ruaha River Catchment. Hydrological modelling using Soil and Water Assessment Tool (SWAT Model) was done to quantify the impact of land use and land cover dynamics on catchment water </span><span style="font-family:Verdana;">balance and sediment loads. The calibration and validation of the SWAT</span><span style="font-family:Verdana;"> model were performed using sequential uncertainty fitting (SUFI-2). The results showed that, for the given LULC change, the average annual surface runoff increased by 2.78 mm while average annual total sediment loading increased by 3.56 t/ha, the average annual base flow decreased by 2.68 mm, ground water shallow aquifer recharge decreased from 2.97 mm and a slight decrease in average annual ground water deep aquifer recharge by 0.14 mm. The model predicts that in the future, there will be a further increase in both surface runoff and sediment load. Such changes, increased runoff generation and sediment yield with decreased base flow have implications on the sustenance flow regimes particularly the observed reduced dry season river flow of the Little Ruaha River, which in turn cause adverse impacts to the biotic component of the ecosystem, reduced water storage and energy production at Mtera Hydroelectrical dam also increasing the chances of flooding at some times of the year. The study recommends land use planning at the village level, and conservation agricultural practices to ameliorate the current situation. Developing multidisciplinary approaches for integrated catchment management is the key to the sustainability of Little Ruaha River catchment.</span></span> 展开更多
关键词 Land Cover Land Use Sediment Loading surface runoff SWAT Model
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Simulation of surface runoff in theWujiang River watershed based on GIS 被引量:2
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作者 TANG Congguo LIU Congqiang 《Chinese Journal Of Geochemistry》 EI CAS 2007年第3期284-289,共6页
Surface runoff in the Wujiang River watershed was simulated by a GIS-based method using precipitation, hydrology data, and land-use data. The volume of surface runoff is chiefly controlled by climates, topographical c... Surface runoff in the Wujiang River watershed was simulated by a GIS-based method using precipitation, hydrology data, and land-use data. The volume of surface runoff is chiefly controlled by climates, topographical characteristics and types of land use at the watershed. Five subwatersheds that can represent the whole watershed were chosen and their average annual precipitation, average annual surface runoff and current land use were calculated respectively in the grid model of the Wujiang River watershed based on the climate and hydrology data from 1965 to 2000 and the land-use data acquired in the year of 2000. Surface runoff is assumed to be a function of precipitation and land use and the multiple regression tool is used to determine the relationship between surface runoff, precipitation and present land use. Thus, the rainfall-runoff model for each land-use type has been established. When calibrating these models, the results show that the percent errors are all below 7%, which indicates that the accuracy of this simulation is high. 展开更多
关键词 分水岭 表面径流 底流 乌江
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Analysis of soluble chemical transfer from soil to surface runoff and incomplete mixing parameter identification
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作者 Ju-xiu Tong Jin-zhong Yang Bill X.Hu 《Water Science and Engineering》 EI CAS CSCD 2015年第3期217-225,共9页
A two-layer mathematical model proposed by Tong et al. (2010) was used to predict soluble chemical transfer from soil into surface runoff with ponded water on the soil surface. Infiltration-related incomplete mixing... A two-layer mathematical model proposed by Tong et al. (2010) was used to predict soluble chemical transfer from soil into surface runoff with ponded water on the soil surface. Infiltration-related incomplete mixing parameter γ and runoff-related incomplete mixing parameter a in the analytical solution of the Tong et al. (2010) model were assumed to be constant. In this study, different laboratory experimental data of soluble chemical concentration in surface runoff from initially unsaturated and saturated soils were used to identify the variables γ and a based on the analytical solution of the model. The values of γ and a without occurrence of surface runoff were constant and equal to their values at the moment when the surface runoff started. It was determined from the results that γ decreases with the increase of the ponded water depth, and when the initial volumetric water content is closer to the saturated water content, there is less variation of parameter γ after the occurrence of surface runoff. As infiltration increases, the soluble chemical concentration in surface runoff decreases. The values of parameter a range from 0 to 1 for the fine loam and sand under the controlled infiltration conditions, while it can increase to a very large value, greater than 1, for the sand under the restrained infiltration conditions, and the analytical solution of the model is not valid for experimental soil without any infiltration if a is expected to be less than or equal to 1. The soluble chemical concentrations predicted from the model with variable incomplete mixing parameters γ and α are more accurate than those from the model with constant γ and α values. 展开更多
关键词 surface runoff Incomplete mixing parameter Analytical solution Soluble chemical
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Wetland Purification Pattern for Surface Runoff Pollution of Coastal Highway in Liaoning Province
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作者 Yanbo ZHAO Wenzhi YAN Hongwei YAN 《Asian Agricultural Research》 2015年第1期44-47,共4页
Taking surface runoff of Coastal Highway in Liaoning Province as research object,this paper analyzed water quality characteristics of runoff and flow rules of pollutants. It proposed using constructed wetland treatmen... Taking surface runoff of Coastal Highway in Liaoning Province as research object,this paper analyzed water quality characteristics of runoff and flow rules of pollutants. It proposed using constructed wetland treatment technique in the drainage system from the perspective of effectively removing major pollutants. Using the constructed wetland k- C* model and relevant experience,parameters of constructed wetland can be obtained. The basic model is as follows: constructed wetland lies in two sides of the road,and surface runoff sewage is collected and treated separately with 1 km road section as the collection unit. The wetland area in one side is 191. 6 m2,average water depth is 0. 5 m,wetland width is 8 m,and wetland length is 24 m. 展开更多
关键词 surface runoff runoff POLLUTION CONSTRUCTED wetlan
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Assessment of the Effects of Poultry Litter on Surface Runoff Water Quality from Agricultural Lands
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作者 Sudarshan K. Dutta Shreeram P. Inamdar +1 位作者 J. Tom Sims Alyssa Collins 《Journal of Water Resource and Protection》 2010年第5期413-423,共11页
The use of pelletized poultry litter (PPL) as a substitute for inorganic fertilizers is increasingly being en-couraged in states like Delaware which have a considerable surplus of poultry litter. However, we know very... The use of pelletized poultry litter (PPL) as a substitute for inorganic fertilizers is increasingly being en-couraged in states like Delaware which have a considerable surplus of poultry litter. However, we know very little about the impacts of PPL on runoff water quality and whether it is an environmentally-sound and sus-tainable alternative to inorganic fertilizer. To address these questions we compared the exports of nutrients (NH4-N, NO3-N and PO4-P) and trace elements (As, Cu, and Zn) in surface runoff from agricultural plots receiving PPL, raw poultry litter (RPL), urea and no-fertilizer (control) treatments. The study was conducted on agricultural land located in Middletown, Delaware with corn as the cover crop. The experimental plots were 5 m wide and 12 m long with reduced tillage and no-tillage management practices. Sampling was con-ducted for six natural rainfall events from April through August 2008. Nutrient (NH4-N, NO3-N and PO4-P) exports from plots receiving PPL were less than those with urea or raw litter applications. While exports of trace elements from the PPL treatment exceeded those from urea, they were much lower than the corre-sponding exports from the RPL treatments. Mass exports of nutrients and trace elements were correlated with event size (rainfall amount) but were not correlated with timing of event (days since litter application). Results from this study suggest that the use of PPL in combination with no-tillage may provide an environ-mentally safe alternative to synthetic fertilizers. 展开更多
关键词 POULTRY LITTER surface runoff Water Quality TILLAGE Best Management Practices NUTRIENTS TRACE Elements
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Integration of Point and Remote Sensing Data for Monitoring Surface Runoff around Madinah City, Saudi Arabia
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作者 ElSayed Ali Hermas Ibrahim Mohammed El-Barodi Khalid Al-Ghamdi 《Advances in Remote Sensing》 2015年第4期287-302,共16页
In response to sporadic rainy storms, the fluvial catchments in the northern, eastern and southern regimes of Medina City produce surface runoff that varies in the frequency and magnitude. The determination of the mos... In response to sporadic rainy storms, the fluvial catchments in the northern, eastern and southern regimes of Medina City produce surface runoff that varies in the frequency and magnitude. The determination of the most frequently flowing catchment(s) through each precipitation event and the spatial characteristics of surface runoff still represent gaps in understanding the hydrological processes associated with flash floods in arid environments. The lack of data in particular precipitation records at reliable temporal and spatial scales is considered one of the essential constraints in understanding these issues. The integration of point precipitation records and the multi-temporal satellite imagery such as LandSat TM and the Tropical Rainfall Monitoring Mission (TRMM) helped retrieve significant surface runoff events through two decades of the last century around Madinah City. The spectral signatures of surface runoff have been clearly identified from the optical remote sensing images acquired after each precipitation event. Investigating the spectral signatures of surface runoff along with its corresponding precipitation records from both Madinah climatic station and the TRMM monthly precipitation indicated that 1) there is no specific threshold of the amount of precipitation required for developing surface runoff;2) while Madinah climatic station provided records of precipitation on the majority of surface runoff, it did not provide records on some monitored surface runoff events;3) the spatial distribution and magnitude of the monthly precipitation of the TRMM images of 1998 have been conformed with all surface runoff events developed in W. Al-Aqeeq;and 4) W. Al-Aqeeq is considered the most frequently flowing valley around Madinah City because it developed surface runoff in response to all the precipitation events. These results emphasize the necessity of establishing a number of climatic and gauge stations in selective locations within the drainage basins around Madinah City. This proposition can facilitate studying the various rainfall and runoff characteristics for designing proper surface water harvesting strategy. 展开更多
关键词 surface runoff REMOTE Sensing TRMM Madinach CITY DEM
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Surface Treatments Effect on Rainfall Canopy Interception and Runoff-Rainfall Ratio for in-Field Rainwater Harvesting
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作者 Weldemichael Abraha Tesfuhuney Leon Daniel Van Rensburg Sue Walker 《Journal of Agricultural Science and Technology(A)》 2013年第6期423-435,共13页
The purpose of this study was to ascertain the effectiveness of surface treatments to quantify the partitioning of rainwater falling on the runoff strips and basins as well as to determine the fraction of rainwater av... The purpose of this study was to ascertain the effectiveness of surface treatments to quantify the partitioning of rainwater falling on the runoff strips and basins as well as to determine the fraction of rainwater available to intercept by maize canopy and infiltrate into the root zone. The rainfall canopy interception (RCI) was estimated as a function of basin leaf area ratio per rain event. The runoffrainfall (RR) ratio was determined for both a single rainfall event and the whole growing season. Infiltration ratio of basin to runoff area was analysed for every unit millimeter of water that infiltrate in the runoff section, some additional of water will infiltrate in the basin area. The plateau value of RCI-rainfall relationships rendered about double in the wider (1.0-1.1 mm) compared to the narrow runoff strips (0.5-0.6 mm). Statistically, the combined surface treatments (RSL x ML) affected the RR ratio with higher efficiency in bare 1 m runoff (27%) and the lower efficiency group (〈 10%) is associated with the widest runoff length covered with mulch. Variations in fractions of rainwater that can infiltrate into basins and runoffareas can lead one to select alternative strategies for water harvesting techniques. 展开更多
关键词 surface treatments rainfall canopy interception runoff rainfall ratio infiltration ratio.
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