Water Resources Management In Watershed Research Articles

Improved hydrological modelling and ET estimation in watershed with irrigation interference

Evapotranspiration (ET) is the true water consumption of the watershed and is key to achieving water conservation. The accurate estimation of ET by distributed hydrological model can provide an important basis for watershed water resources management. At present, the traditional approach calibrating distributed hydrological model parameters by runoff has low accuracy in watersheds under human interference. The reason is that the measured runoff is no longer natural due to various human activities such as river water withdrawals, reservoir regulation and inter-basin water transfer. While using ET for model calibration can effectively overcome this interference, making it a more accurate approach for watersheds under human interference. Therefore, we calibrated the Soil and Water Assessment Tool (SWAT) model using PMLV_2 ET in Ziya River under frequent human activities. The results indicated that calibrating the model with remote sensing ET could improve the model’s simulation performance, increasing the NS from 0.65 to 0.83. However, the annual ET calculated by the model was 21.7% lower than PMLV_2 ET. The largest underestimation was for the annual ET of cropland (agricultural ET), which was underestimated by 24.4%. This is partly because the model did not account for irrigation evaporation from cropland. Therefore we used Landsat 8 data to extract the planting areas of winter wheat, which consumes the highest irrigation water in the Ziya River Basin, from 2013 to 2018. The planting areas and irrigation regimes of winter wheat were incorporated into the SWAT model to calculate the agricultural ET. The results indicate that the agricultural ET calculated by the SWAT model that considers irrigation evaporation is 6.9% lower than that of PMLV_2 ET. The simulation accuracy of ET is significantly improved. This study provides a reference for accurate estimation of agricultural ET and a basis for ET management.

Identification of surface water - groundwater nitrate governing factors in Jianghuai hilly area based on coupled SWAT-MODFLOW-RT3D modeling approach

A comprehensive understanding of the key controlling factors on NO3-N spatiotemporal distribution in surface and groundwater is of great significance to nitrogen pollution control and water resources management in watershed. Hence, the coupled SWAT-MODFLOW-RT3D model was employed to simulate nitrate (NO3−) fate and transport in Huashan watershed system. The model was calibrated using a combination of stream discharge, groundwater levels, NO3-N in-stream loading and groundwater NO3-N concentrations. The simulation revealed the significant spatiotemporal variations in surface water-groundwater nitrate interactions. The annual average percolation of NO3− from rivers to groundwater was 171.5 kg/km2 and the annual average discharge NO3− content from groundwater into rivers was 451.9 kg/km2 over the simulation period. The highest percolation of NO3− from rivers to groundwater occurred in April and the highest discharge NO3− content from groundwater into rivers occurred in July. Grassland and agriculture land contributed more nitrate contents in river water and groundwater compared to bare land and forest in the study area and the water exchange was the primary driving force for nitrate interactions in the surface water-groundwater system. Sensitivity analysis indicated that river runoff and groundwater levels were most influenced by the SCS runoff curve number f (CN2) and aquifer hydraulic conductivity (K), which, in turn, significantly affected nitrate transport. Regarding water quality parameters, the denitrification exponential rate coefficient (CDN) had the most pronounced impact on NO3-N in-stream loading and groundwater NO3-N concentrations. This study underscores the central role of surface-groundwater (SW-GW) interactions in watershed-scale nitrate research and suggests that parameters with higher sensitivity should be prioritized in analogous watershed modeling.

Multi-scale flow regimes and driving forces analysis based on different models: a case study of the Wu River basin

Abstract Quantitatively separating the influence of climate change and human activities on runoff is crucial to achieving sustainable water resource management in watersheds. This study presents a framework for quantitative assessment by integrating the indicators of hydrologic alteration, the whale optimization algorithm and random forest (WOA-RF), and the water erosion prediction (WEP-L) models. This framework quantifies the differences in hydrological conditions and their driving forces at multi-timescales (annual, seasonal, and monthly). The results indicate that the runoff of the Wu River has decreased since 2005. Climate factors were found to influence the interannual variation of runoff mainly. Meanwhile, human activities had a more significant impact in autumn, with a relative contribution rate of 59.0% (WOA-RF model) and 70.8% (WEP-L model). Monthly, the picture is more complex, with the results of the WOA-RF model indicating that climate change has a significant impact in July, August, and September (88.8%, 92.7%, and 79.3%, respectively). However, the WEP-L model results showed that the relative contribution of land use is significant in April, May, June, October, and November (51.24%, 64.23%, 63.63%, 53.16%, and 50.63%, respectively). The results of the study can be helpful for regional water allocation.

Base Flow Variation and Attribution Analysis Based on the Budyko Theory in the Weihe River Basin

The composition and change of runoff are closely related to climate change and human activities. To design effective watershed water resources management measures, there is a need for a clear understanding of the impact of climate change and human activities on baseflow and surface runoff. The purpose of this essay is to quantify their impact on the annual total stream flow, surface runoff, and base flow in the Weihe River Basin (WRB) using a two-stage annual precipitation partitioning method, wherein the surface runoff and base flow are separated from the measured total flow by using a one-parameter digital filter method for which the common filter parameter value is 0.925. The stream flow records were split into two periods: 1960–1970 (pre-change period) and 1971–2005 (post-change period) based on the hydrological breakpoints detected. We found that climate change and human activities have different impacts on base flow and surface runoff. We attributed the decrease in surface runoff due to climate change accounting for 76–78%, while we determined that human activities were responsible to the decrease in base flow accounting for 59–73% of the total observed change. We concluded that both climate change and human beings contributed to the hydrologic change through different hydrological processes: climate change dominated the surface runoff change, while human influences controlled the base flow change. To achieve the expected goals of ecological restoration, appropriate measures must be taken by watershed management in the WRB to mitigate the likely impacts of climate change on water hydrology.

基于SWAT模型的汾河流域生态补水研究

PDF HTML阅读 XML下载 导出引用 引用提醒 基于SWAT模型的汾河流域生态补水研究 DOI: 10.5846/stxb202106291724 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目（2017YFA0605001） Study on ecological water supplement in Fenhe River Basin based on SWAT Model Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:随着人类对于河流的开发利用日益增强，显著改变了河流的天然径流过程，生态供水不足成为流域生态系统健康的重要制约因素。以山西省汾河流域为研究区，基于天然和实测径流数据，利用SWAT模型分别模拟了流域近30年天然径流和近10年跨流域调水情况下现状径流过程，并在此基础上对流域各河道生态流量及现状径流量进行时空量化，探讨了不同生态流量标准下生态缺水量在时间和空间上的变化情况。研究结果表明：（1）汾河流域各河道生态流量时空差异明显，汛期（0.50-18.80m3/s）河道生态流量需求显著高于非汛期（0.05-1.81m3/s），总体分布特征为中下游干流远高于上游支流；（2）在Tennant法的不同生态流量标准下，汾河流域非汛期生态流量保障情况整体优于汛期，高频缺水区主要分布在支流，呈上下游分散分布；（3）在中等级生态流量标准下，流域约84%的区域能保障基本生态流量需求，关键缺水区为岚河、潇河、浮山县及浍河地区；（4）建议流域生态补水在时间上侧重汛期补水，空间上侧重高频缺水地区，基于流域生态缺水量时空分布特征分配跨流域调水资源，提高水资源利用效率。研究从时空上量化了跨流域调水工程实施后流域生态流量满足程度，可以为未来流域水资源管理提供有效指导。 Abstract:Facing the increasingly serious water shortage problem, with the increasing demand for water resources, the development and utilization of rivers by human beings have been enhanced, which significantly changed the natural hydrological process of basins. The basic ecological water demand of rivers cannot be guaranteed, and the shortage of ecological water supply has become an important factor restricting the health of watershed ecosystem. In order to effectively guarantee the river ecological flow, the Soil and Water Assessment Tool (SWAT) model was used to simulate the natural runoff and the current runoff process with inter basin water transfer in Fenhe River Basin of Shanxi Province based on the natural and measured hydrological data. First, based on the SWAT model, the monthly natural runoff for about 30 years and the monthly current runoff after the implementation of inter basin water transfer projects in recent 10 years were simulated in the Fenhe River Basin. Second, based on the improved Tennant method, the ecological flow values under different ecological flow criteria were quantified in each river channel in flood season and non-flood season. Last, the temporal and spatial distribution characteristics of ecological flow and ecological water shortage were analyzed in the whole basin. The results showed that:(1) the ecological flow of each channel showed significantly temporal and spatial differences, with the values were 0.05-1.81 m3/s for non-flood season and 0.50-18.8 m3/s for flood season. The overall distribution characteristics were that the ecological flow in the middle and lower reaches was much higher than that in the upstream tributaries. (2) Under different ecological flow criteria of Tennant method, the satisfaction of ecological flow in non-flood season was better than that in flood season, and the areas with high-frequency of water shortage were mainly distributed in the upstream and downstream tributaries. (3) Under the medium-level environmental flow standards, about 84% of the basin could guarantee the basic ecological flow demand, and the key water shortage areas were Lanhe, Xiaohe, Fushan County and Huihe River basin. (4) The ecological water supplement of the basin should focus on flood season in time and areas with high frequency of water shortage in space, and the water resources of inter-basin water transfer projects should be allocated based on the spatial and temporal distribution characteristics of ecological water deficiency to improve the utilization efficiency of water. In conclusion, this study quantified the satisfaction degree of ecological flow after the implementation of inter basin water transfer projects in time and space, which can provide effective guidance for watershed water resources management. 参考文献 相似文献 引证文献

Advances in Eco-hydrology and Watershed Water Resources Management in China

Advances in Eco-hydrology and Watershed Water Resources Management in China

The landuse change detection in Taleghan catchment

The effects of global warming, climate change and landuse changes on catchment water balance and quality have become the main concerns in the watershed water resources management in recent years. One such area is the Taleghan watershed in the Northwest of Tehran, the Iran’s capital with an area of 930.62 km2. This watershed has undergone excessive landuse changes during the last two decades due to the dam construction. Both dam construction and its reservoir have highly increased the land prices in this area, causing drastic landuse changes. Digital Image Processing (DIP) technique was introduced to recognize landuse change detection for different periods. To evaluate landuse change, the whole upper part of the watershed was considered over two decades of 1987 to 2007. The results of image processing indicated that after the approval of dam building, the watershed rangeland areas declined from 82.7 to 35.4%. Land ownership caused drastic degradation in landuse during that period. As the consequence, dry farming activities lost their stability and severely declined. The good rangeland (G1) area which was initially 32287 ha in 1987, decreased to 5693 ha by late 2007 due to overgrazing, weak landuse management and climate change. This is a significant change during the last 20 years from 34.5 to 5.90%. On the other hand, concurrently, the poor rangeland increased from 19.0 to 23.4%. Immigration and rush for land purchase and suburb house construction increased the percentages of rural area to urban textures which translates to 3.1 km2 in 2007 compared with its original density of 1.74 km2 in 1987. Key words: Taleghan, landuse, image processing.

Modelagem da potencialidade hídrica das águas subterrâneas da sub-bacia do rio Siriri, Sergipe, Brasil, com base em Sistema de Informações Geográficas e técnicas de Sensoriamento Remoto

The use of Geographic Information System (GIS) and Remote Sensing for modeling groundwater potential give support for the analysis and decision-making processes about water resource management in watersheds. The objective of this work consisted in modeling the groundwater water potential of Siriri river sub-basin, Sergipe state, based on its natural environment (soil, land use, slope, drainage density, lineament density, rainfall and geology) using Remote Sensing and Geographic Information System as an integration environment. The groundwater potential map was done using digital image processing procedures of ENVI 4.4 software and map algebra of ArcGIS 9.3®. The Analytical Hierarchy Method was used for modeling the weights definition of the different criteria (maps). Loads and weights of the different classes were assigned to each map according to their influence on the overall objective of the work. The integration of these maps in a GIS environment and the AHP technique application allowed the development of the groundwater potential map in five classes: very low, low, moderate, high, very high. The average flow rates of wells confirm the potential of aquifers Sapucari, Barriers and Maruim since they are the most exploited in this sub-basin, with average flows of 78,113 L/h, 19,332 L/h and 12,085 L/h, respectively.

Application of the Distributed Hydrological Model, TOPNET, to the Big Darby Creek Watershed, Ohio, USA

Evaluation of the applicability and utility of watershed hydrologic models in different hydro-geologic and soil conditions is necessary for a range of spatial scales and to assess the utility of these models as watershed water resources management tools. This study presents the application of the hydrological model TOPNET to the Big Darby Creek watershed, Ohio, United States. It focuses on the simulation modeling of stream flow in the watershed based on meteorological data for the eight year period of 1992–1999. Visual comparison of time series plots and statistical measures namely, Nash-Sutcliffe efficiency (NS), coefficient of correlation (R2), and the percent bias (PBIAS) were used to assess the model performance. The statistical model evaluation results indicated that the model has a relatively high confidence and can give a good representation of the flow hydrographs for the watershed. For the calibration period simulations of annual stream flow were accurate with a mean R2 and NS of 86% and 85% for the Big Darby at Darbyville gaging station. For the little Darby at West Jefferson gaging station a mean R2 of 81% was obtained while the NS averaged 78%. Further analysis based on the aggregation of the water years into wet seasons and dry seasons, the model was also able to adequately simulate stream flow for both gaging stations and for both low flow periods and high flow periods. Statistical analysis for the validation period also yielded high R2 values of 88% and 83% for the Darby at Big Darby at Darbyville gaging station and Little Darby at West Jefferson gaging station respectively. The worst PBIAS obtained for both calibration and validation period was 18% and this is better than recommended values for satisfactory daily simulations of ±25% for PBIAS. The encouraging simulation results obtained in this study shows the utility and usefulness of the TOPNET model in hydrological modeling and ultimately as a water resources management tool.