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1.
洪水研究包括径流与淹没两种模式。为了探究流域降雨产汇流与淹没情况、提高洪水预报精度,本研究在传统流域水文模型的基础上耦合二维水动力学模型,建立水文-水动力耦合模型。以我国吉林温德河流域为研究实例,模拟了2017年“7·13”洪水在下游口前镇所处子流域洪水淹没过程。首先对基础数据进行预处理,建立HEC-HMS水文模型并进行参数优化后,最终获得流量过程水文结果作为水动力学模型边界条件,之后建立HEC-RAS二维水动力学模型对重要子流域进行淹没模拟。耦合模型计算结果显示,水文模型经多参数优化流量模拟的NSE系数为0.988,水动力计算最大淹没水深达9.3 m相对误差为-5.2%。从泛洪模拟结果来看,子流域上游部分的农田大量被淹,淹没水深范围在0.5~2.0 m,平均流速基本在1 m/s以下。下游口前镇内最大淹没水深接近1 m,水流速度0.2 m/s至1.5 m/s,与实际的淹没情况相吻合。研究表明,所建水文水动力耦合模型模拟计算的结果准确率较高,对具有复杂水文、水力条件的流域的洪水预报具有重要的指导意义。 相似文献
2.
SWAT模型对高精度土壤信息的敏感性研究 总被引：2，自引：0，他引：2
土壤信息是SWAT模型的重要输入数据,通常认为,土壤信息的精度直接影响着模拟结果的准确性。本文以美国Brewery Creek流域(19.5km2)为例,在其他输入不变的情况下,通过比较不同精度土壤数据(美国农业部SSURGO土壤图与SoLIM方法获得的土壤图)的模拟径流,分析SWAT模型对高精度土壤信息的敏感性。应用结果显示,在模型的校正前后,两种土壤数据的径流模拟结果均近似,差别并不显著。这表明在小流域水文模拟中,SWAT模型的径流模拟对高精度土壤信息的敏感性较弱,模拟径流不能很好的体现一定精度基础上土壤信息的差别。本文将此现象主要归因于:SWAT模型所采用的SCS-CN径流计算方法,在计算CN值(Curve Number)时将不同土壤类型综合到四个土壤水文组的做法,概括了土壤信息,模糊了土壤之间的属性差别,损失了土壤精度信息。本研究发现了SCS-CN径流计算方法在利用高精度土壤数据时存在的问题,并进行了分析,为水文模拟中参数的确定和数据的准备提供了参考。 相似文献
3.
人口增长、气候变化、制度变迁、城市化等均会导致土地利用/覆被的变化,进而引起流域水文过程（截留、入渗、蒸散发和地下水补给等）和水循环过程的改变。当前,由于逐年土地利用/覆被数据获取困难、水文模型本身计算缺陷等问题,所有在流域尺度上开展的借助水文模型进行的土地利用/覆被变化影响下的水文模拟研究都存在一个共同缺点,就是采用的水文模型并不能逐年调用土地利用/覆被数据,即水文模型无法真实体现或模拟土地利用/覆被的时空变化。SWAT作为一个广泛应用的分布式水文模型,在其模拟期内,不能逐年调用土地利用/覆被数据,即在进行水文模拟时忽略了土地利用/覆被时间上的变化,这可能会影响其在土地利用/覆被变化剧烈地区（如黑河中游）的应用。黑河流域是典型的内陆河流域,也是中国西北地区第二大内陆河流域。黑河中游是黑河流域的径流耗散区。本文针对SWAT模型在考虑土地利用/覆被变化时的缺点,对其进行了改进并开发出能够逐年调用土地利用/覆被数据的LU-SWAT模型。在土地利用/覆被变化剧烈的黑河中游对SWAT和LU-SWAT模型的径流模拟效果进行比较,发现LU-SWAT模型更适用于黑河中游水循环模拟。 相似文献
4.
流域水文模型研究的进展 总被引：14，自引：2，他引：12
流域水文模型是对流域上发生的水文过程进行模拟计算的数学模型 ,在水文过程模拟中 ,对流域内的产流 ,坡面汇流以及河道汇流过程的模拟是很重要的。坡面产汇流模型模拟从降水到流域产流和流域坡面汇流的水文子过程 ,河道演进模型模拟河网汇流水文子过程 ,现有的水文模型大多数是没有考虑水文变量和水文参数空间变化的概念性水文模型。随着地理信息技术的发展 ,考虑水文变量和水文参数空间变化的分布式水文模型得到了极大的重视与发展 ,而且 ,遥感技术的发展满足了分布式水文模型对空间信息的需求. 相似文献
5.
针对川中丘陵区紫色土坡耕地严重水土流失,选取典型代表李子溪流域为研究区,构建了其SWAT的模型数据库,包括地形、土壤、气象和土地利用数据库。并利用赵家祠水文站1970-1979年的实测径流和泥沙资料,对该流域的SWAT模型参数进行率定再采用1980-1986年的实测资料,对模型的适用性进行验证,同时用相对误差Re和Nash确定性系数Ens评价模拟效果。结果显示,径流和泥沙模拟相对误差均在±15%范围以内,Nash确定性系数均大于等于0.70,说明SWAT模型对李子溪流域年、月径流和年泥沙量的模拟精度较高。同时模拟值与实测值和降雨量的变化趋于一致。可见,用SWAT模型模拟和预测雨量较为丰沛、土壤侵蚀较严重的紫色丘陵地区的产流产沙是实用、可行的。 相似文献
6.
降水数据的准确性和时空分辨率成为水文过程模拟的关键。卫星遥感降水资料的日益丰富为资料缺乏区的水文模拟带来了新的突破。本研究拟在资料缺乏、下垫面复杂,观测难、建模难的柴达木盆地高寒内陆河流域—巴音河中上游,基于近5年的TMPA 3B42、GPM IMERG V5及GPM IMERG V6逐日降水数据和气象站点观测数据建立SWAT模型,采用流域出口径流数据及不同的参数化方案分别率定4个模型,比较和探究不同数据在巴音河流域的适用性。结果表明：① 在月、年尺度上,实测降水数据及TMPA 3B42 V07对应的SWAT模型径流模拟效果较好,前者模拟精度较后者仅高6%~12%,且二者对于流域水量平衡的刻画均较准确。说明TMPA 3B42数据对应的径流模拟结果误差相对较小,可直接用于高寒内陆河流域水文模拟;② GPMIMERG V5数据对应的那什系数NSE值为0.13（月）、-1.58（年）,误差百分数PBIAS值为41.2%（月、年）,均方根误差与标准误差比率RSR值为0.93（月）、1.61（年）,其径流模拟误差较大,模拟效果不可信,说明GPMIMERG V5数据集并不适用于巴音河流域水文模拟;③ GPMIMERG V6-F对应的月径流模拟结果明显优于GPMIMERG V5-F,前者模拟精度较后者提高4倍,但其模拟的年径流对应的NSE值为-0.12,RSR值为1.09。该研究可为资料缺乏的高寒内陆河流域生态水文过程模拟提供参考。 相似文献
7.
城市暴雨内涝模拟模型优化与精度验证 总被引：2，自引：0，他引：2
本文采用“Vegetation-Impervious Surface-Soil”模型和线性光谱混合分解方法,获取像元中不透水面、植被、土壤覆盖信息,用于计算SCS模型产流参数综合CN（Curve Number）值;基于土地利用类型,采用经验值与数值实验逐步求精相结合的方法,确定水动力汇流模型参数曼宁系数,并用实测积水数据验证两次参数修正的模拟效果。以上海中心城区为例进行验证,研究结果表明：①将采用V-I-S模型得到的不透水面、植被、土壤信息设定CN值,能够降低积水分布的极值化现象,提高SCS产流模型产流量和产流分布精度;②采用经验法和数值模拟逐步求精法,按土地利用类型设定曼宁系数,使各时段最大积水深度高于原模型,说明曼宁系数是汇流模型的敏感参数。 相似文献
8.
我国水文气象站少且空间分布不均衡,水文模型参数难以获取极大限制了其在防洪预警中的应用。针对新安江水文模型在无水文资料地区应用的局限性,本文提出了一种基于遥感信息的新安江模型参数推求方法,实现了可率定的模型参数的推求:利用土壤特性与土地覆被遥感信息推求流域张力水蓄水容量;基于流域土地覆被遥感信息提取不透水面积比;利用流域土壤特性及叶面积指数遥感影像间接推算流域自由水蓄水容量。利用本文方法推求了老灌河流域新安江水文模型参数并进行了日径流模拟,实验结果表明,流域水文模拟中利用遥感信息推求出的模型参数的准确性可以达到80%以上。 相似文献
9.
ArcGIS环境下DEM的坡长计算与误差分析 总被引：2，自引：0，他引：2
坡长是水土保持、土壤侵蚀和环境评价等研究中的基本因子。在GIS环境下,坡长的提取是基于格网DEM进行的,其结果受到DEM精度、DEM结构、流向提取算法和栅格距离计算方式的影响。在确定分辨率和精度的DEM下,坡长计算误差主要来自流向提取算法和栅格距离计算方式。本文对这两种DEM坡长计算误差源进行了详细的分析,指出集成到ArcGIS软件中的坡长计算模型D8存在较大缺陷,尽管栅格距离计算方式对坡长影响最大误差为8.9%,并可通过统计方式实现整体坡长的修正,但D8算法的单流向特性使得水流方向变得确定和不连续,进而导致坡面单元坡长产生较大误差,因此,利用D8算法进行数值模拟计算需要考虑其精度问题。同时应提高坡长计算的准确性,需要发展更为完善的流向计算方法和坡长计算模型。 相似文献
10.
流域过程模拟是地理学研究和流域科学管理的有效工具。在应用需求的推动下,长时段、高空间分辨率的多过程综合模拟逐渐兴起,流域过程模拟所需的计算量越来越大,亟需借助并行计算技术来提高效率。流域过程模拟并行计算的现有研究,大多为针对特定模型的个例研究,缺乏对指导各类流域过程模型并行计算的共性思路和原则进行讨论和梳理。首先,对可指导流域过程模拟并行计算的地理规律进行了分析,从空间、子过程和时间3 个角度,探讨了空间等级层次结构、空间相互作用、子过程间依赖关系、时空动态变化等地理规律,对流域过程模拟并行计算的指导作用;然后,根据地理规律在并行计算中所发挥作用和适用范围的不同对其分类;最后,结合2 个实例,对地理规律的流域过程模拟并行计算进行了分析和验证,旨在对流域过程模拟并行计算理论和方法的发展与应用提供借鉴。 相似文献
11.
《山地科学学报》2015,(2)
In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT) model. The model was tested at the Juntanghu watershed on the northern slope of the Tian Shan Mountains, Xinjiang,China. We compared the performances of temperature-index method and energy balanced method in SWAT model by taking Juntanghu river basin as an application example(as the simulation experiment was conducted in Juntanghu River, we call the energy balanced method as SWAT-JTH). The results suggest that the SWAT snowmelt model had overall Nash-Sutcliffe efficiency(NSE) coefficients ranging from 0.61 to 0.85 while the physical based approach had NSE coefficients ranging from 0.58 to0.69. Overall, on monthly scale, the SWAT model provides better results than that from the SWAT-JTH model. However, results generated from both methods seem to be fairly close at a daily scale. Thestructure of the temperature-index method is simple and produces reasonable simulation results if the parameters are well within empirical ranges. Although the data requirement for the energy balance method in current observation is difficult to meet and the existence of uncertainty is associated with the experimental approaches of physical processes, the SWAT-JTH model still produced a reasonably high NSE. We conclude that using temperature-index methods to simulate the snowmelt process is sufficient, but the energy balance-based model is still a good choice to simulate extreme weather conditions especially when the required data input for the model is acquired. 相似文献
12.
《山地科学学报》2015,(4)
The objective of this study was to assess runoff discharge and sediment yield from Da River Basin in the Northwest of Vietnam using Soil and Water Assessment Tools(SWAT) model.The SWAT model was calibrated and validated using the observed monthly stream flows and sediment yield at selected gauging stations.The results indicated that SWAT generally performs well in simulating runoff and sediment yield according to Nash-Sutcliffe efficiency(NSE), Observation's standard deviation ratio(RSR), and percent bias(PBIAS) values.For runoff, the values of NSE, RSR, and PBIAS were 0.98,0.02, and 3.69 during calibration period and 0.99,0.01, and 1.56 during validation period, respectively.For sediment yield, the efficiency was lower than the value of NSE, RSR, and PBIAS during calibration period were 0.81, 0.19, and-4.14 and 0.84, 0.16, and-2.56 during validation period, respectively.The results of the study indicated that the vegetation status has a significant impact on runoff and sediment yield.Changes in land use type between 1995 and2005 from forest to field crop and urban strongly contributed to increasing the average annual runoff from 182.5 to 342.7 mm and sediment yield from101.3 to 148.1 ton-1 ha.Between 2005 and 2010, adecrease of both runoff(from 342.7 to 167.6 mm) and sediment yield(from 148.1 to 74.0 ton-1 ha) was due to the expansion of forested area and application of soil conservation practices.The results of this study are important for developing soil and water conservation programs, extending future SWAT modelling studies and disseminating these results to other regions in Vietnam. 相似文献
13.
1INTRODUCTIONIntheHuanghe(Yellow) Riverbasin, soilerosionisaseriousproblem,whilerunoffandsedimentyieldsim-ulation hasnotbeenextensivelystudiedonthebasisofGIS(GeographicInformationSystem) and dis-tributedhydrologicalmodel.Inthisstudy,theLushiwatershed,whichislocatedattheupstreamoftheLushiHydrologicalStationintheLuoheRiver—thebiggesttributary oftheHuanghe Riveranddown-streamofXiaolangdiDam,isselectedasthestudyarea.ThelevelofsoilerosioninLushiwatershedismoderatein theHuangheRiverbas… 相似文献
14.
淮河流域是水体遭受营养盐污染较严重的地区,本研究选择淮河上游的淮滨流域（淮滨站以上,流域面积1.6万km2）为研究对象,首先构建了淮滨流域SWAT水文水质模型,然后利用2011—2017年淮滨站实测的月径流和月氨氮浓度对SWAT模型进行了校正与验证,最后基于全球气候模型（GCM）气象数据,预测了未来30年（2020—2029年、2030—2039年、2040—2049年）不同气候变化情境（RCP2.6、RCP4.5、RCP6.0、RCP8.5）下的径流、氨氮浓度和非点源总氮负荷。结果发现,径流在校正期和验证期的Nash-Suttcliffe系数均为0.79,氨氮在校正期和验证期的Nash-Suttcliffe系数均高于0.5,表明模型的适用性良好。研究发现本研究区施肥量与土地利用类型是非点源氮负荷空间分异的主导因素。2020—2049年,不同气候变化情景下,本研究区的降水量和气温均为增长趋势。假如保持基准期（2011—2016年）污染排放强度,仅考虑气候变化影响,流域内非点源污染总氮负荷将比基准期最多增加31.8%,流域出水口淮滨站的年均氨氮浓度将最多减小42.6%。本研究可以为气候变化下淮滨流域的水文水质管理提供科学支撑。 相似文献
15.
《山地科学学报》2021,(10)
Climate change has significantly affected hydrological processes and increased the frequency and severity of water shortage, droughts and floods in northeast China. A study has been conducted to quantify the influence of climate change on the hydrologic process in the Tao'er River Basin(TRB), one of the most prominent regions in northeast China for water contradiction. The Soil and Water Assessment Tool(SWAT) model was calibrated and validated with observed land use and hydro-climatic data and then employed for runoff simulations at upper, middle and lower reaches of the river basin for different climate change scenarios. The results showed that a gradual increase in temperature and decrease in annual precipitation in the basin was projected for the period 2020-2050 for both representative concentration pathways(RCP) 4.5 and 8.5 scenarios. The climate changes would cause a decrease in annual average runoff at basin outlet by 12 and 23 million m3 for RCP4.5 and 8.5, respectively. The future runoff in the upstream and midstream of the basin during 2020-2050 would be-10.8% and-12.1% lower than the observed runoff compared to the base period for RCP4.5, while those would be-5.3% and-10.7% lower for RCP8.5. The future runoff will decrease at three hydrology stations for the assumed future climate scenarios. The results can help us understand the future temperature and precipitation trends and the hydrological cycle process under different climate change scenarios, and provide the basis for the rational allocation and management of water resources under the influence of future climate change in the TRB. 相似文献
16.
Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interactions interchange numerous times throughout the middle reaches, making streamflow simulation a challenge in endorheic river watersheds. In this study, we modified the linear-reservoir groundwater module in SWAT (Soil and Water Assessment Tools, a widely used hydrological model) with a new nonlinear relationship to better represent groundwater processes; we then applied the original SWAT and modified SWAT to the Heihe River Watershed, the second largest endorheic river watershed in Northwest China, to simulate streamflow. After calibrating both the original SWAT model and the modified SWAT model, we analyzed model performance during two periods: an irrigation period and a non-irrigation period. Our results show that the modified SWAT model with the nonlinear groundwater module performed significantly better during both the irrigation and non-irrigation periods. Moreover, after comparing different runoff components simulated by the two models, the results show that, after the implementation of the new nonlinear groundwater module in SWAT, proportions of runoff components changed-and the groundwater flow had significantly increased, dominating the discharge season. Therefore, SWAT coupled with the non-linear groundwater module represents the complex hydrological process in the study area more realistically. Moreover, the results for various runoff components simulated by the modified SWAT models can be used to describe the hydrological characteristics of lowland areas. This indicates that the modified SWAT model is applicable to simulate complex hydrological process of arid endorheic rivers. 相似文献
17.
Muhammad ADNAN KANG Shi-chang ZHANG Guo-shuai Muhammad Naveed ANJUM Muhammad ZAMAN ZHANG Yu-qing 《山地科学学报》2019,(5)
This paper presents an assessment of the Soil and Water Assessment Tool(SWAT) on a glaciated(Qugaqie) and a non-glaciated(Niyaqu) subbasin of the Nam Co Lake. The Nam Co Lake is located in the southern Tibetan Plateau, two subbasins having catchment areas of 59 km~2 and 388 km~2, respectively. The scores of examined evaluation indices(i.e., R~2, NSE, and PBIAS) established that the performance of the SWAT model was better on the monthly scale compared to the daily scale. The respective monthly values of R~2, NSE, and PBIAS were 0.94, 0.97, and 0.50 for the calibration period while 0.92, 0.88, and -8.80 for the validation period. Glacier melt contribution in the study domain was simulated by using the SWAT model in conjunction with the Degree Day Melt(DDM) approach. The conjunction of DDM with the SWAT Model ensued improved results during both calibration(R~2=0.96, NSE=0.95, and PBIAS=-13.49) and validation (R~2=0.97, NSE=0.96, and PBIAS=-2.87) periods on the monthly time scale. Average contribution(in percentage) of water balance components to the total streamflow of Niyaqu and Qugaqie subbasins was evaluated. We found that the major portion(99.45%) of the streamflow in the Niyaqu subbasin was generated by snowmelt or rainfall surface runoff(SURF_Q), followed by groundwater(GW_Q, 0.47%), and lateral(LAT_Q, 0.06%) flows. Conversely, in the Qugaqie subbasin, major contributor to the streamflow(79.63%) was glacier melt(GLC_Q), followed by SURF_Q(20.14%), GW_Q(0.13%), and LAT_Q(0.089%). The contribution of GLC_Q was the highest(86.79%) in July and lowest(69.95%) in September. This study concludes that the performance of the SWAT model in glaciated catchment is weak without considering glacier component in modeling; however, it performs reasonably well in non-glaciated catchment. Furthermore, the temperature index approach with elevation bands is viable in those catchments where streamflows are driven by snowmelt. Therefore, it is recommended to use the SWAT Model in conjunction with DDM or energy base model to simulate the glacier melt contribution to the total streamflow. This study might be helpful in quantification and better management of water resources in data scarce glaciated regions. 相似文献