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Evaluation and modeling of runoff and sediment yield for different land covers under simulated rain in a semiarid region of Brazil

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International Journal of Sediment Research 2018年第2期33卷 117-125页

作者： Richarde Marques da Silva Celso Augusto Guimares Santos José Yure Gomes dos Santos Department of Geosaences Federal University of Paraíba Department of Civil and Environmental Engineering Federal University of Paraíba Federal University of Western Bahia Center for Humanities

This paper quantifies the runoff and sediment yield for four different land covers in a semiarid region of Brazil. The WESP model, a distributed, event-oriented runoff-erosion model, was applied and its physical parameters, NSand KR, were adjusted based on observed runoff and sediment yield data using simulated rainfall with an average intensity of 53 mm h-1. The sediment yield obtained was 53.02 kg ha-1(caatinga vegetation), 231.96 kg ha-1(bare soil), 309.75 kg ha-1(beans), and 847.38 kg ha-1(corn). The results showed that caatinga cover yields the lowest erosion and runoff when compared to the other *** results also show that the sediment yield and runoff values simulated with NS, KI, and KR parameters were well calibrated, within acceptable deviations. The caatinga vegetation was more effective in protecting the soil, when compared to the other types of coverage. The beans and corn covers had the highest values of runoff and sediment yield, even higher than those observed for bare soil.

关键词： runoff Erosion Semiarid region WESP model

Effect of spatial scale on runoff coefficient: Evidence from the Ethiopian highlands

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International Soil and Water Conservation Research 2018年第4期6卷 289-296页

作者： Tesfaye Mebrate Lemma Gizaw Desta Gessesse Asfaw Kebede Kassa Desalegn Chemeda Edossa Debre Berhan University Debre BerhanEthiopia Water and Land Resources Center Addis AbabaEthiopia Haramaya Institute of Technology HaramayaEthiopia South-Man Engineering ManitobaWinnipegCanada

The runoff coefficient (RC) is the ratio between the runoff and rainfall amounts and is scale dependent, which is due in part to the heterogeneity of watershed characteristics. This study quantified the spatial scale effects on runoff using long-term rainfall-runoff data on runoff plots and small watersheds. Effect of spatial scale on RC was studied for 12 runoff plots (2m by 15m) and three small watersheds (113-477 ha) in the highlands of Ethiopia using a total of 4397 and 13,92515-day cumulative pairs of rainfall and runoff data at watershed and runoff plot scales, respectively. The observed average RC of runoff plots was extrapolated based on the extent of representation of a particular watershed in terms of slope, land use, cover and soil type. The weighted RC of plots was then compared with the observed RC of the watershed to determine a scale factor for extrapolation. A decrease in RC from plot to the watershed was observed in Anjeni and Andit Tid watersheds, while an increase in RC in Maybar watershed illustrates the role of specific watershed conditions in determining the scale effect. This, in turn, suggests that the variation in scale factor is not well explained by the difference in the area alone. The scale effect of runoff generation was better explained by extrapolating the RC based on the representation of different watershed characteristics. Thus, extrapolation exercises in runoff modeling and scaling efforts of soil and water conservation practices should consider the scale effect cautiously.

关键词： runoff coefficient Spatial scale Rainfall-runoff relation Ethiopian highlands

Copula-based identification of the non-stationarity of the relation between runoff and sediment load

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International Journal of Sediment Research 2017年第2期32卷 221-230页

作者： Shengzhi Huang Pei Li Qiang Huang Guoyong Leng State Key Laboratory Base of Eco-Hydraulic Engineering in Arid Area Xi'an University of Technology Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences

It is important to identify the non-stationarity in the relation between runoff and sediment load under the backdrop of the changing *** relation helps to further understand the mechanisms of runoff and sediment yield.A copula-based method was used to detect possible change points in the relation between runoff and sediment load in the Wei River Basin(WRB),China,where soil erosion is a very severe *** modified Mann-Kendall trend test method was applied to obtain the trends of runoff and sediment load spanning 1960-2010 at monthly and annual ***,the causes of the identified non-stationarity of the relation between runoff and sediment load were roughly analyzed from the perspective of climate change and human *** indicated that:(1)the runoff and sediment load in the Jinghe and Wei rivers were generally characterized by noticeably decreasing trends at both monthly and annual timescales;(2)both the Jinghe and Wei rivers had a common change point(2002),implying that the stationarity of the relation between runoff and sediment load in the Jinghe and Wei River was invalid;(3)human activities including increasing water consumption and growing application of soil conservation practices are dominant factors resulting in non-stationarity in the relation between runoff and sediment load in the *** study provides a new idea for identifying the non-stationarity of multivariate relation in the hydro-meteorological field under the background of the changing environment.

关键词： Copula-based method runoff Sediment load Non-stationarity Change point Human activities

Effects of Caragana Korshinskii Kom. cover on runoff, sediment yield and nitrogen loss

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International Journal of Sediment Research 2010年第3期25卷 245-257页

作者： Guan-Hua ZHANG1,Guo-Bin LIU2?, and Guo-Liang WANG31 Ph.D., College of Resource and Environment, Northwest A and F University YangLing, Shaanxi 712100, China, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, YangLing Shaanxi 712100, China. 2 Prof., Researcher. Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, YangLing Shaanxi 712100, China, College of Resource and Environment, Northwest A and F University, YangLing, Shaanxi 712100, China, 3 Assistant Researcher, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, YangLing Shaanxi 712100, China. Ph.D. College of Resource and Environment Northwest A and F University YangLing Shaanxi 712100 China Institute of Soil and Water Conservation Chinese Academy of Science and Ministry of Water Resources YangLing Shaanxi 712100 China Prof. Researcher. Institute of Soil and Water Conservation Chinese Academy of Science and Ministry of Water Resources YangLing Shaanxi 712100 China College of Resource and Environment Northwest A and F University YangLing Shaanxi 712100 China Assistant Researcher Institute of Soil and Water Conservation Chinese Academy of Science and Ministry of Water Resources YangLing Shaanxi 712100 China

Soil erosion is serious in the Loess Plateau of China. Deposition of the eroded sediment in lakes or rivers may lead to eutrophication, because the sediment carries a lot of nutrients. Field experiments were conducted to study soil erosion and loss of nitrogen (N) from a 15o hillslope with 30% (low) or 80% (high) coverage of the shrub Caragana korshinskii Kom. A bare soil plot was used for the comparison. The results showed that Caragana korshinskii cover significantly reduced runoff and soil erosion. In comparison to the bare soil plot, the vegetation covered plots had about 20% less runoff and 65% less sediment. In general, the concentration of N in both runoff water and the eroded sediment decreased with time and approached a steady value. However, the species of nitrate nitrogen (NO3) was exceptional which increased with time slightly. The soil erosion caused an N loss of about 250 mg/m2 for the bare soil plot, the low coverage of Caragana korshinskii reduced the N loss by 20% and the high coverage of Caragana korshinskii reduced the N loss by 40%. Moreover, the amount of total N in eroded sediment was 2 to 3 times higher than the value in runoff water. In the total N loss, the organic N was about 75-80%. Nevertheless, inorganic N in runoff water was 5 to 10 times higher than the value in eroded sediment. The species of NO3 was obviously higher than the species of ammonium nitrogen (NH4). NO3 was the main species of inorganic N loss and was about two thirds of total. The organic N was the main species of N in the eroded sediment.

关键词： C. korshinskii cover runoff Sediment Nitrogen loss Simulated rainfall

Correlation Analysis of the runoff of the Rivers and the Seisms in China

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Science China Chemistry 1993年第5期36卷 630-640页

作者：汤懋苍董文杰张建杨良 Lanzhou Institute of Plateau Atmospheric Physics Academia Sinica Lanzhou 730000 PRC

In recent hundred years the annual discharge variations of the Changjiang River (represented by the Yichang station) and the Huanghe River (represented by Shanxian and Tangnaihe, respectively) have closely related to the geographical distribution of the earthquakes coming about in China in the same year, Both the occurrence of the destructive seism or seismic swarm in the river basins and the disappearance of the shocks in the east and south of the basins are the conditions that the Changjiang and Huanghe Rivers are the high flow while that the strong earthquake of magnitude 7 or more occurred in North China is the condition for the Changjiang low flow year and that of 6 or more in the Qilian Mountains area is for the Huanghe River. In the latter part of this paper, a 2-year sample is given to explain that the conditions of the 2 rivers being high flow years are that the north-south seismic belt is active and in the meanwhile no seism occurred in South China, and those of the low flow year are that the strong quake(s) occurred in the north and south of China and quiet in the north-south seismic belt. The analysis indicates that the seismically active area is in general consistent with the high value of soil temperature anomalies at the depth of 3.2 m, which may help to explain the physical relationship between the seism and the precipitation field.

关键词： annual runoff annual selsmic field soil temperature field the Huanghe River the Changjiang River.

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A model for simulating the response of runoff from the mountainous watersheds of inland river basins in the arid area of northwest China to climatic changes

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Science China Earth Sciences 1999年第S1期42卷 52-63页

作者：康尔泗程国栋蓝永超金会军 State Key Laboratory of Frozen Soil Engineering Lanzhou Institute of Glaciology and Geocryology Chinese Academy of Sciences

A model for simulating the response of monthly runoff from the mountainous watersheds to climatic changes is developed. The model is based on the modifications to the HBV runoff model, and therefore represents the characteristics and runoff generation processes of inland river basins in the arid area of northwest China. Taking the mountainous watershed of an inland river, the Heihe River originating from the Qilian Mountains and running through the Hexi Corridor as an example, the monthly runoff changes under different climate scenarios are simulated. The simulation indicates that, during the years from 1994 to 2030, if the annual mean air temperature increases by 0.5℃ , and precipitation keeps unchanged, then the runoff of May and October will increase because of the increase of the snow melt runoff, but the runoff of July and August will decrease to some extent because of the increase of evaporation, and as a result, the annual runoff will decrease by 4 % . If the precipitation still keeps unchanged, and the air temperature increases by 1.0℃ , in addition to the increase of runoff of May and June, the runoff of July and August will decrease in a larger amount, making the annual runoff decrease by 7.11 % . If the air temperature keeps unchanged, the increase of annual precipitation by 10% will cause the increase of runoff by 5 .27% ; while the increase of precipitation by 20% will cause the increase of runoff by 12.35% . When the air temperature increases by 0.5℃ and the precipitation increases by 10% , the runoff will increase only by 1.62% .

关键词： inland river basins runoff from mountainous watersheds climatic changes response.

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Impacts of land uses on runoff and soil erosion A case study in Hilkot watershed Pakistan

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International Journal of Sediment Research 2011年第3期26卷 343-352页

作者： ZOKAIB S. NASER Gh. School of Engineering University of British Columbia-OkanaganCanada

In certain areas of the Hindu Kush-Himalayas（HKH）,ecological situation is depleting day by day and approaching to the point of no return through gradual environmental *** soil erosion from most of the areas is a serious threat to sustainable agriculture and sediment accumulation in down stream *** extensive study in the Hilkot watershed,a catchment of Terbala Dam, was started by the People and Resource Dynamics Project in *** objectives of this study were to calculate annual runoff and soil losses from different land uses and compare their seasonal distribution at plot *** experimental plots based on land use classification（***, forests,agricultural,and pasture lands）were *** falls in the monsoon region,about 38% rainfall occurred in the monsoon period（July to September）,while in the pre-monsoon（March to June）and the winter period（October to February）received 35%and 27%of the total rainfall, *** annual rainfall in the watershed was 1160 *** runoff and soil loss pattern varied among different land use *** all the erosion plots,almost 50%of the runoff and soil loss occurred during the monsoon period and was negligible during *** mean maximum runoff was from the degraded plot（674 m;/ha/y）,while minimum was observed from the pasture plot（310 m;/ha/y）.Average runoffs on other land uses were 529 and 460 m;/ha/y,from the forest and agriculture plots,*** soil loss from all land uses ranged between 0.3 to 16.3 t/ha. Average maximum soil loss was recorded from the degraded plot（6.5 t/ha/y）and average minimum （1.8 t/ha/y）was on the pasture ***,average soil from other plots was 3.3 and 3.4 t/ha/y, measured from the forest and agricultural plots,respectively.

关键词： runoff Soil loss Land use Seasonal distribution Hindu Kush-Himalayan region

SWAT-based runoff and sediment simulation in a small watershed,the loessial hilly-gullied region of China:capabilities and challenges

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International Journal of Sediment Research 2012年第2期27卷 226-234页

作者： Lin-jing QIU Fen-li ZHENG Run-sheng YIN College of Forestry Northwest A&F University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources College of Resources and Environment Northwest A&F University Department of Forestry Michigan State University

Model calibration and validation are necessary before applying it for scenario assessment and watershed *** study presented the methodology of evaluating Soil and Water Assessment Tool(SWAT) and tested the feasibility of SWAT on runoff and sediment load simulation in the Zhifanggou watershed located in hilly-gullied region of *** runoff and sediment event data from 1998-2008 were used in this study;data from 1998-2003 were used for calibration and 2004-2008 for *** evaluation statistics for the daily runoff simulation showed that the model results were acceptable,but the model underestimated the runoff for high-flow *** sediment load simulation,the SWAT performed well in capturing the trend of sediment load,while the model tended to underestimate sediment load during both the calibration and validation periods. The disparity between observed and simulated data most likely resulted from limitations of the existing SCS-CN and MUSLE methods in the *** study indicated that the modification of SWAT components is needed to take rainfall intensity and its duration into account to enhance the model performance on peak flow and sediment load simulation during heavy rainfall season.

关键词： Loessial hilly-gullied region runoff Sediment load SWAT Watershed

Correction of measurement errors on sediment concentration sampled by stirring-sampling method from traditional runoff collection tanks

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International Journal of Agricultural and Biological Engineering 2022年第6期15卷 134-142页

作者： Yuhan Huang Mingquan Zhao Hui Zhao Tingwu Lei Ju Tang Wei Wang Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Monitoring Center of Soil and Water Conservation Ministry of Water ResourcesBeijing 100053China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationCAS and MWRYangling 712100China College of Resources and Environment Southwest UniversityChongqing 400716China College of Engineering China Agricultural UniversityBeijing 100083China

Stirring-sampling method is a widely adopted method to measure sediment concentrations in collection tanks of runoff plots,but with high systematic measurement *** research aimed to advance an approach for building correction equations to remove measurement errors in designed sediment concentration *** data of sediment measurement from the stirring-sampling method,with four representative soils,under the designed sediment concentrations(1,2,5,8,10,20,50,80,100,200,500,800,and 1000 kg/m^(3))were used to demonstrate the correction methodological *** correction methods(step-wise correction and universal correction)were suggested for the trial in this study based on the distribution of measurement *** the step-wise correction,the correction equations were made with a series of linear functions without intercept for the low concentration group(0-20 kg/m^(3)),a series of linear functions with intercept for the high(20-200 kg/m^(3))and extremely high(200-1000 kg/m^(3))concentration groups,*** correction equations were a series of power functions in the universal *** the step-wise correction,most of the relative errors of correction sediment concentrations were smaller than 15%and 10%under high and extremely high concentration groups,but the corrected accuracy was not good in the sediment concentration of 1,2,5 kg/m^(3)with the corrected relative errors of 0.20%-206.07%.For the universal correction,the corrected relative errors(0.19%-31.81%)of the four soils were low under the condition of extremely high sediment concentrations,but other corrected accuracies weren’t good with the corrected relative errors of 0.68%-1154.71%.The corrected accuracy of step-wise correction is higher than that of the universal correction,but the universal correction is more *** results indicated that the correction equations could efficiently revise the measurement errors of the tested soils and that this method can be ge

关键词： runoff sediment concentration measurement error correction stirring-sampling method