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61.
Haykel Sellami Isabelle La Jeunesse Sihem Benabdallah Marnik Vanclooster 《水文科学杂志》2013,58(8):1635-1657
AbstractThe SWAT model was tested to simulate the streamflow of two small Mediterranean catchments (the Vène and the Pallas) in southern France. Model calibration and prediction uncertainty were assessed simultaneously by using three different techniques (SUFI-2, GLUE and ParaSol). Initially, a sensitivity analysis was conducted using the LH-OAT method. Subsequent sensitive parameter calibration and SWAT prediction uncertainty were analysed by considering, firstly, deterministic discharge data (assuming no uncertainty in discharge data) and secondly, uncertainty in discharge data through the development of a methodology that accounts explicitly for error in the rating curve (the stage?discharge relationship). To efficiently compare the different uncertainty methods and the effect of the uncertainty of the rating curve on model prediction uncertainty, common criteria were set for the likelihood function, the threshold value and the number of simulations. The results show that model prediction uncertainty is not only case-study specific, but also depends on the selected uncertainty analysis technique. It was also found that the 95% model prediction uncertainty interval is wider and more successful at encompassing the observations when uncertainty in the discharge data is considered explicitly. The latter source of uncertainty adds additional uncertainty to the total model prediction uncertainty.
Editor D. Koutsoyiannis; Associate editor D. GertenCitation Sellami, H., La Jeunesse, I., Benabdallah, S., and Vanclooster, M., 2013. Parameter and rating curve uncertainty propagation analysis of the SWAT model for two small Mediterranean watersheds. Hydrological Sciences Journal, 58 (8), 1635?1657. 相似文献
62.
《水文科学杂志》2013,58(3):588-601
Abstract The Biobío River basin is of high strategic importance for Chilean development, at both the regional and the national levels. For this reason, advances in the general understanding of, and in the capacity to describe and predict, in a spatially explicit way, the impact of climate and anthropogenic forcing on the hydrology of the Biobío basin are urgently needed. The work presented here attempts to set the basis for future modelling applications within the Biobío basin by analysing the applicability of a readily available modelling tool, the SWAT model, to one of its sub-basins. Modelling results show that the model performs well in most parts of the study basin. The SWAT model application for the Vergara basin confirms that SWAT is a useful tool and can already be used to make a preliminary assessments of the potential impacts of land-use and climate changes on basin hydrology. 相似文献
63.
64.
运用数值模拟建立青藏高原兹格塘错流域土壤、植被、气候等的空间和属性数据库;接着,借助分布式流域尺度水文模型（SWAT模型）,对兹格塘错1956—2006年间的流量进行模拟实验;最后,反演50年来兹格塘错流域水文过程,测试流域温度、降水和蒸发组合的敏感因子对湖泊水量变化的效应,探讨50年来湖泊水量对气候变化的响应。模拟实验的边界条件设置为自然地形、土壤、植被覆盖,其中土壤资料包括有机质含量、粒径等理化参数。模拟结果表明：兹格塘错的年平均流量为6.3m3/s,流量高峰集中在8月至10月,并且由于融雪补给的关系,3月出现另一个流量高峰;模拟结果与遥感解译所得到的结果吻合较好。敏感实验表明：兹格塘错流域内温度、降水和蒸发组合的敏感因子实验具有高原特征,即高原湖泊的水文过程和湖泊流量变化有着较为敏感的响应关系;兹格塘错流量受降水的影响最大,随着降水的增加,流量有所增加;在温度升高的情况下,流域蒸发量增加速度大,兹格塘错流量增加的效应不明显,而在冷湿模式下,流域蒸发量降低,兹格塘错流量增加显著。 相似文献
65.
The modified Soil Conservation Service curve number (CN) method is widely used in long‐term continuous models to predict daily surface runoff. However, it has been shown that this method gives poor results in reproducing peak flows in high rainfall periods. This is because there is an inaccuracy stemming from the model algorithm as it adjusts the daily runoff curve number as a function of soil moisture content at the end of the previous day. This paper proposes an alternative daily based curve number technique that can provide better prediction of daily runoff during the high flow season. The proposed method uses the temporally weighted average curve number (TWA‐CN) to estimate daily surface runoff, while considering the effect of rainfall during a given day as well as the antecedent soil moisture condition. To test the applicability of the TWA‐CN method, it was incorporated with the long‐term, continuous simulation watershed models SWAT and SWAT‐G. Simulations were conducted for the Miho River watershed located in the middle of South Korea. The graphical displays and statistics of the determination coefficient (R2) and the Nash–Sutcliffe model efficiency (NSE) of the observed and simulated daily runoff indicated that the modified SWAT with the TWA‐CN method may provide better runoff prediction (R2 = 0·837, NSE = 0·833) than the original SWAT (R2 = 0·815, NSE = 0·824). Likewise, the determination coefficient (R2 = 0·816) and the Nash–Sutcliffe efficiency (NSE = 0·834) for the modified SWAT‐G are also higher than the original version (R2 = 0·782, NSE = 0·825). It is expected that the improved capability in predicting surface runoff using the suggested CN estimate method will provide a sound contribution to the accurate simulations of water yield. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
66.
Modelling blue and green water resources availability in Iran 总被引：7，自引：0，他引：7
Knowledge of the internal renewable water resources of a country is strategic information which is needed for long‐term planning of a nation's water and food security, among many other needs. New modelling tools allow this quantification with high spatial and temporal resolution. In this study we used the program Soil and Water Assessment Tool (SWAT) in combination with the Sequential Uncertainty Fitting program (SUFI‐2) to calibrate and validate a hydrologic model of Iran based on river discharges and wheat yield, taking into consideration dam operations and irrigation practices. Uncertainty analyses were also performed to assess the model performance. The results were quite satisfactory for most of the rivers across the country. We quantified all components of the water balance including blue water flow (water yield plus deep aquifer recharge), green water flow (actual and potential evapotranspiration) and green water storage (soil moisture) at sub‐basin level with monthly time‐steps. The spatially aggregated water resources and simulated yield compared well with the existing data. The study period was 1990–2002 for calibration and 1980–1989 for validation. The results show that irrigation practices have a significant impact on the water balances of the provinces with irrigated agriculture. Concerning the staple food crop in the country, 55% of irrigated wheat and 57% of rain‐fed wheat are produced every year in water‐scarce regions. The vulnerable situation of water resources availability has serious implications for the country's food security, and the looming impact of climate change could only worsen the situation. This study provides a strong basis for further studies concerning the water and food security and the water resources management strategies in the country and a unified approach for the analysis of blue and green water in other arid and semi‐arid countries. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
67.
山区降水较集中,但降水测站多位于山谷或人口密集区,代表性差。遥感和再分析降水产品能提供时空分布连续的数据,不受地形条件限制。柴达木盆地中心属干旱荒漠区,水是制约该区开发的首要条件,其四周属高寒山区,降水相对较多,但降水监测十分薄弱。为获取该区相对精确的降水时空分布信息,本文评估了4套高分辨率降水产品（CMADS、TRMM、GPM和MSWEP）的适用性。首先基于地面站点数据评估它们在不同时空尺度上的精度,并分析它们在柴达木盆地的空间分布和年内分配特征。然后,以盆地东南隅的无测站山区香日德河流域为研究区,利用降水产品驱动SWAT模型来评估它们的分布式水文模拟适用性。结果表明：(1) MSWEP在年、月尺度上与站点降水的吻合程度最高（R≥0.79,PBIAS=0.5%）,其次是GPM和TRMM,CMADS精度最低（R≥0.64,PBIAS=5.8%）;(2)从降水精度与站点高程的关系来看,降水产品在相对低海拔区容易高估站点降水,而在相对高海拔区常低估实际降水;(3)在香日德河流域,MSWEP(NSE=0.64)在基准期（2009—2012年）的径流模拟表现明显好于其它降水产品（NSE=0.3... 相似文献
68.
为在径流模拟中充分考虑水库的综合调蓄作用,改善了SWAT（The Soil and Water Assessment Tool）模型的水库算法,在水库模块中增加基于水库供水发电调度规则的水库出流模拟算法,以提高径流模拟精度。选择东江流域作为典型流域,分别应用改进前后的SWAT模型进行径流模拟,并分析模型改进的效果,结果表明：修改后的SWAT模型解决了水库模拟出流量在非汛期过低、汛期过大的问题,能更有效地模拟枯季径流和洪峰流量,明显提高了月径流及日径流的模拟精度,其中,月径流模拟中率定期内R2提高了0.06~0.22,NS提高了0.06~0.52,验证期内R2提高了0.1~0.19,NS提高了0.12~1.22;日径流模拟中率定期内R2提高了0.04~0.16,NS提高了0.04~0.46,验证期内R2提高了0.11~0.15,NS提高了0.15~1.21。 相似文献
69.
基于数字滤波法和SWAT模型的灞河流域基流时空变化特征研究 总被引：1，自引：0，他引：1
将国内外应用较广的数字滤波法和分布式水文模型SWAT相结合,在进行基流时间特征分析的基础上,通过修正基流退水系数α、模型效率评价、重新运行模型、GIS空间插值和趋势分析等方法,创新性地实现了基流空间特征的可视化表达。研究结果表明：① 2001~2012年灞河流域年均基流指数（BFI）为0.43,总体呈增加的趋势。年降水量与年径流、年基流均呈明显的正相关关系,与年基流指数呈明显的负相关关系;② 基流年内变化较为稳定,在时间上存在秋季>春季>夏季>冬季、汛期>非汛期的关系。枯水期的基流指数高达0.78,表明基流是枯水期河流的主要补给来源;③ 灞河流域基流在空间上表现为自东南向西北、自上游向下游逐渐增加的趋势,这种空间分异规律是由流域的地势和河流流向决定的。 相似文献
70.
Concerns about police militarization have become an important public policy issue since the aggressive police response to the 2014 protests in Ferguson, Missouri, where police officers used military-style equipment to confront protestors. This event was a stark visual reminder that many U.S. police departments have used federal programs to acquire surplus military equipment, including weapons, armored vehicles, and body armor. We explore the geographies and histories of one the most important programs, called 1033, which supplies police with military equipment under the rationale of prosecuting the War on Drugs. We show that the legal blurring of the police and the military has been ongoing for decades at the national scale but this has resulted in an uneven landscape of police militarization at the county scale. We also investigate one of the most common global arguments for why police become militarized, which is the presence of Special Weapons and Tactics-style paramilitary teams, finding little support for that claim. More geographic inquiry is needed to understand the trajectories, causes, and consequences of police militarization. 相似文献