河北平原典型小流域降雨入渗补给规律研究

准确计算降雨入渗补给量是评价平原区地下水资源量的基础,传统的年补给系数法未考虑降雨特征、土壤墒情等因素影响,导致评价结果精度不高。本研究以河北平原下博和沧县运西两个典型小流域为例,采用动态分析法研究次降雨的入渗补给过程。结果显示以7 d为时间间隔适合作为划分次降雨的标准,次降雨量加土壤含水量(P+SW)与降雨入渗补给量(P_r)相关性最好,优于次降雨量(P)和次降雨量加前期雨量(P+P_a);动态分析法计算的降雨入渗补给量较传统降雨入渗系数法,精度提高22%~40%,且年补给系数法高估了河北平原区的年地下水补给量。本研究为河北中东部平原准确评价降雨入渗补给量提供了技术参考,对支撑区域的地下水合理开发利用及地下水超采综合治理具有较强的科学和实践意义。     

Statistical Approach for Comprehensive Planning of Watershed Development Through Artificial Recharge

The purpose of the study is to demonstrate that cross-correlation analyses can contribute to the artificial recharge study in regional level of shallow aquifer. Correlations between hydrologic time series data were analyzed to identify the hydrogeologic location for potential artificial recharge in district Surat, Gujrat, India. The natural groundwater-level fluctuations and rainfall data were used for the analyses. The effective development of groundwater resources is essential for a country like India. India receives a good amount of average annual rainfall (114?cm) but most of its part goes waste as runoff. Over exploitation of groundwater due to increasing population is an additional cause of water crisis that results in the reduction in per capita availability of water in the country. Artificial recharge is essential for effective development of groundwater resources. An effort has been made to evaluate the suitable recharge zone considering rainfall by arresting runoff to restore groundwater conditions using a statistical technique. Groundwater system in a basaltic terrain where the top weathered regolith forms shallow aquifer the water table variation is directly influenced with temporal rainfall variation. Understanding of this relation is of critical importance to management of groundwater resources. A diagnostic relationship between recharge time series and water level time series is used to serve the purpose to determine the best site for groundwater recharge.     

基于无资料地区地下水资源量计算方法的研究

地下水是指储存在地面以下饱和岩土孔隙、裂隙及溶洞的水。地下水资源量是指某时段内地下含水层接收降水、地表水体、侧向径流及人工回灌等项渗透补给量的总和。其中,地表水体渗透补给量由湖泊（水库、坑塘）周边渗透补给量、河道及渠系渗透补给量和田间灌溉入渗补给量组成。对无资料地区通常采用临近站地形、地貌等相似的地区借用其现有的水文资料来计算地下水资源量。文章对此进行探讨研究。     

Assessing Impacts of Conservation Measures on Watershed Hydrology Using MIKE SHE Model in the Face of Climate Change

Climate change triggers changes in temperature, precipitation, evapotranspiration, etc. and has a significant impact on water resources in many regions. Considering the increasing scarcity of water as a result of climate change, conservation of water and groundwater recharge have become crucial factors for water resources planning and management. In this paper, an attempt is made to study the detailed hydrological behaviour of a treated watershed using physically based distributed hydrological modelling system MIKE SHE to assess the impact of conservation measures on watershed hydrology considering future climate change. Three hypothetical management scenarios are simulated for the period 2010–2040. RegCM4 regional climate model is used in the study for RCP 4.5 and RCP 8.5 scenarios. Detailed hydrological water balance is extracted for individual years from 1979 to 2009 to compare relevant components. The evaluation for base period shows 10.06% reduction in surface runoff and 11.33% enhancement in groundwater recharge. Further simulation with RCP 4.5 and RCP 8.5 scenarios show notable reduction in surface runoff and increase in groundwater recharge. The structures in the micro-watershed influence the surface runoff and increase infiltration into the soil, resulting in higher groundwater recharge. MIKE SHE simulations for various structures management scenarios establish the role of conservation measures in reducing surface runoff and enhancing groundwater recharge under substantial effect of climate change. The results will assist in decision-making on watershed development plans in quantitative terms, including planning for water conservation measures in the face of climate change.

     

Groundwater Recharge Assessment for the Kalahari Catchment of North-eastern Namibia and North-western Botswana with a Regional-scale Water Balance Model

Groundwater is the only source of drinking water for the inhabitants of the Kalahari. Thus understanding spatial and temporal variations in groundwater recharge is very important and a regional-scale water balance model has therefore been set up for a 209,149 km² catchment in north-eastern Namibia and north-western Botswana. The model has a spatial resolution of 1.5 × 1.5 km, daily model time-steps, and climatic input parameters for 19 years are used. The distributed, GIS-based, process-oriented, physical water balance model (MODBIL) used in this study considers the major water balance components: precipitation, evapotranspiration, groundwater recharge, and surface runoff/interflow. Mean precipitation for the study area is 409 mm a⁻¹, while mean actual evapotranspiration is 402 mm a⁻¹ and mean groundwater recharge is 8 mm a⁻¹ (2% of mean annual precipitation). The recharge pattern is mainly influenced by the distribution of soil and vegetation units. Groundwater recharge shows a high inter- and intra-annual variability, but not only the sum of annual precipitation is important for the development of groundwater recharge; a large amount of precipitation in a relatively short period is more important. Published independent data from the Kalahari in Namibia, Botswana and the Southern African region under similar climatic conditions are used to verify the modelling results.     

包气带岩性结构对降雨入渗能力的影响

降水是鄂尔多斯盆地风沙滩地区地下水的主要补给来源之一,区内包气带岩性结构影响着降雨入渗补给地下水的过程。试验以该区两组均质结构(风积沙、风化砂岩)与两组层状"上粗下细"结构(风积沙-风化砂岩组、风积沙-淤泥质沙组)中水势和水量变化情况分析不同岩性中降雨入渗过程的差异性。结果表明:均质结构和层状"上粗下细"结构降雨入渗过程均呈线性变化过程,但是均质结构的累计入渗量为层状结构的1.5～3.0倍,更有利于降雨入渗;层状"上粗下细"结构中,岩性由粗到细水力梯度增大1.48～1.78倍,下覆细质土较大的水势梯度反映了其低渗性,且降水入渗过程与上覆粗质土无关,主要由下层细质土控制,下层细质土颗粒越细,入渗量越小,较细细质土的入渗量约为较粗细质土的0.66倍。研究结果对于提高鄂尔多斯盆地风沙滩地区水资源评价的准确性具有重要意义。     

太湖地区典型小流域地下水储量动态模拟与分析

对太湖地区典型小流域的近地表地质特征进行系统野外试验,分析近地表土层土壤和岩层结构特征,初步确定了含水层计算参数;采用三维地下水流数值模拟方法概化水文地质条件,识别与验证模型参数。结果表明:地表水补给地下水的量约是地下水补给地表水总量的2倍,山溪型小流域的地表地下水交互过程趋于单向交换,即河道水补给地下水。从含水层储水量变化看,除去蒸散发,通过地下通道流失的水量占据总水量的相当比重,且地下储水的减少量主要依赖降雨入渗进行补给。所建立的模型能够较好地反映研究区实际的水文地质条件,揭示地表水和地下水的交互量的变化过程,并定量研究流域水量平衡动态关系,可为变化环境下的地下水保护和滨湖区的地下水潜流计算研究提供预测分析依据。     

Development and testing of soil water regime simulation models

Four soil water balance simulation models corresponding to specific soil-crop relations were developed for application to irrigation planning and management. The forms of the models were inferred from 18 months of weekly and bi-weekly soil water data and daily meteorological data. Soil water change is computed by budgeting of the water inputs and outputs, namely precipitation, evapotranspiration, drainage, and runoff. Actual evapotranspiration was found to be dependent on both potential evapotranspiration and soil water content. Empirical drainage functions were developed, but semi-empirical ones inferred from theoretical knowledge of soil hydraulic properties performed at least as well. Runoff functions were required to explain only exceptional conditions of very heavy rainfall. A quantitative assessment of each model's prediction accuracy was performed. The uncertainty that can be expected for any predicted value with a cumulative probability of 0.95 is in all cases within an interval of 1% of the soil water content in average conditions.     

不同土地利用/覆被条件下松嫩盆地降水入渗补给量研究

土地利用/覆被条件是降水入渗补给量的主要影响因素,近10年来松嫩盆地土地利用/覆被变化显著.本次研究采WetSpass模型计算土地利用/覆被条件不同对降水入渗补给量的影响.定性分析不同土地利用/覆被类型的转化对降水入渗补给量的影响,并计算1995～2005这10年间,松嫩盆地的土地利用/覆被条件变化对其年均降水入渗补给...     

A MACRO-SCALE SEMI-DISTRIBUTED HYDROLOGICAL MODEL AND APPLICATION TO THE DATONG RIVER VALLEY

1.INTRODUCTION TheYellowRiverisimportantwatersourcein north westChinaandtheHuabeiPlain.Therela tivearidclimateandunreasonablehumanactivities havemadewaterproblemsveryseveresuchas floodthreat,dryriverbedandenvironmentsdeg radation.Theproblemshinderthebasinfromsus tainabledevelopment.Soitisofsignificancetoresearchtheproblemsandmastertherulesofrunoff change.Hydrologicalmodelhasbeenplayinga veryimportantroleasatooltomodelrunoff.A numberofresearchershavedonemuchworkabout runoffsimulationand…     

三峡库区小流域降雨入渗和产流产沙特征试验研究

三峡库区暴雨集中,历时短,强度大,是造成土壤侵蚀的重要因素。为开展对三峡库区小流域降雨入渗和产流产沙特征研究,通过建立三峡库区小流域微缩模型,分别实施降雨强度为60,90,120 mm/h的3场人工模拟降雨,对小流域模型降雨入渗规律和径流侵蚀过程进行了分析。研究结果表明:径流量均随降雨强度的增加而增加,而降雨强度增加入渗的作用仅在一定范围内是有效的;随着降雨的进行,产流强度和入渗率都趋于稳定状态,入渗率服从对数函数规律,产流强度呈幂函数变化;3场降雨中累计产沙量和累计径流量的关系均满足幂函数形式,含沙量和侵蚀量之间呈较好的线性关系。该研究成果可为这一区域的水土流失防治提供重要的科学依据。     

Estimation of Groundwater Balance Using Soil-Water-Vegetation Model and GIS

This study concerns the development of a methodology using modern techniques of data generation (Modeling) and interpretation (GIS) to compute groundwater plausibly at regional scale, alternate to previously established norms. The approach is centered on quantitative estimation of two main parameters-input and output. GIS techniques along with soil vegetation model (CropSyst) have been demonstrated for the calculation of groundwater balance components. Using the developed methodology water resources of the Ludhiana district for the period between, 2000 and 2010 were estimated. The temporal changes in water balance components indicated that the major inputs to the hydrologic system are rainfall and canal water and the major out component are evapotranspiration (ET). Multi-annual (2000 to 2010) average of 719 mm rainfall, 88 mm canal water, 74 mm of groundwater inflow, with annual loss 974 mm as ET, caused 123 mm of net negative groundwater recharge in Ludhiana district. The annual computed rise/fall with the developed methodology closely matched the observed values.     

Post Audit Analysis of a Groundwater Level Prediction Model in Developed Semiconfined Aquifer System

This paper assesses groundwater recharge under conditions of long-term groundwater pumping at the Ravnik pumping site in Croatia and analyses the groundwater level prediction model used in prior aquifer modelling. The results of model calibration revealed a very low net infiltration rate at the start of the pumping site’s operation. As the operation continued, the net infiltration rate slowly increased, while the percentage of infiltrated rainfall scaled up with increasing pumping rates. The predicted recharge of the covering aquitard amounts approximately 14–15 % of the mean annual precipitation. The aquifer recharge takes place from aquitard by seepage. A subsequent simulation of the pumping site’s operation was performed for the 9 years period on the assumption that the pumping rates and the groundwater recharge would be the same as those recorded during the final calibration years. Results show that the post audit measured levels correspond relatively well to the predicted levels and that increasing of the pumping rate causes changes in the water budget in advantage of net groundwater recharge as a consequence of spreading recharge area outside of previous model boundaries.     

基于不同降雨特征的空闲坡耕地产流产沙特征解析

阐明空闲坡耕地产流产沙特征,可为坡耕地水土资源综合治理提供科学依据。以第四纪红黏土发育红壤为研究对象,采用野外径流小区长期定位试验的方法,分析天然降雨条件下的空闲坡耕地产流、产沙特征及其对降雨特征的响应机制。结果表明：空闲坡耕地的土壤侵蚀等级为强烈等级以上,产流、产沙存在逐年降低趋势,与年降雨历时存在一定的负相关,但不显著;产流、产沙主要集中在4-9月,可分别占到全年总量的96.73%和99.35%;小雨雨型几乎无产流、产沙,暴雨雨型以上降雨的产流、产沙贡献率大,其贡献率均在80%以上;降雨量、降雨历时、降雨动能以及降雨侵蚀力对产流的驱动模型呈二次曲线函数关系,最大30 min雨强的驱动模型则呈幂函数关系;降雨动能、降雨侵蚀力以及最大30 min雨强对产沙的驱动模型均呈现幂函数关系,而降雨量和降雨历时的驱动模型分别为一次线性函数和二次曲线函数关系,产流驱动模型的可决系数均大于产沙驱动模型,产流与产沙的关系表现为幂函数关系。     

Integrated Surface–Subsurface Modeling of Fuxianhu Lake Catchment, Southwest China

This paper describes an integrated surface–subsurface modeling study of the Fuxianhu Lake catchment (southwest China). Pollution threats to this important water resource have led to the need to evaluate transport pathways and the overall water balance of the catchment. Catchment inputs to the lake include river inflows, direct overland flow and groundwater discharge, which are incorporated into a mathematical model of the system. Surface runoff and groundwater recharge are estimated using a parsimonious soil–vegetation modeling approach, while groundwater flow is based on the MODFLOW-2005 code. Overland flow and stream discharge are coupled to the groundwater regime through the soil layer and are routed through the catchment to account for surface water flow pathways. The model is tested using the V-catchment benchmark problem and is compared to existing models to demonstrate accuracy and capability. Application of the model to the Fuxianhu catchment provides for the first-order approximation of the average catchment water balance, which comprises such components as evapotranspiration losses (37% of rainfall), surface runoff to the lake (37% of rainfall), and groundwater discharge to the lake (8% of rainfall), amongst others. The computationally efficient approach to surface–subsurface modeling adopted in this investigation presents as an alternative to more complex methods, and allows for the rapid assessment of flow pathways at the catchment scale. An erratum to this article can be found at     

Optimizing the Runoff Estimation with HEC-HMS Model Using Spatial Evapotranspiration by the SEBS Model

Most of the commonly used hydrological models do not account for the actual evapotranspiration (ETa) as a key contributor to water loss in semi-arid/arid regions. In this study, the HEC-HMS (Hydrologic Engineering Center Hydrologic Modeling System) model was calibrated, modified, and its performance in simulating runoff resulting from short-duration rainfall events was evaluated. The model modifications included integrating spatially distributed ETa, calculated using the surface energy balance system (SEBS), into the model. Evaluating the model’s performance in simulating runoff showed that the default HEC-HMS model underestimated the runoff with root mean squared error (RMSE) of 0.14 m³/s (R²?=?0.92) while incorporating SEBS ETa into the model reduced RMSE to 0.01 m³/s (R²?=?0.99). The integration of HECHMS and SEBS resulted in smaller and more realistic latent heat flux estimates translated into a lower water loss rate and a higher magnitude of runoff simulated by the HECHMS model. The difference between runoff simulations using the default and modified model translated into an average of 95,000 m³ runoff per rainfall event (equal to seasonal water requirement of ten-hectare winter wheat) that could be planned and triggered for agricultural purposes, flood harvesting, and groundwater recharge in the region. The effect of ETa on the simulated runoff volume is expected to be more pronounced during high evaporative demand periods, longer rainfall events, and larger catchments. The outcome of this study signifies the importance of implementing accurate estimates of evapotranspiration into a hydrological model.

     

海绵城市LID设施运行效能衰减机理及寿命分析研究综述

为了研究海绵城市LID设施长期受纳降雨径流后填料理化性质的演变规律,揭示设施运行效率的衰减过程及机理,探索设施合理的使用寿命,以海绵城市LID设施为研究对象,从设施填料理化性质与水分入渗和污染净化能力的关系、入渗性能改变及污染物吸附饱和、LID设施运行效能衰减及运行寿命几个方面,通过文献资料综合评述国内外研究的进展与不足。结果表明：现有研究大多围绕LID设施结构、效果与影响机制展开,对其填料理化性质的演变规律、入渗性能改变及污染物吸附饱和等缺乏系统研究,对设施运行效率的阶段性、动态化衰减过程研究鲜见报道,制约设施运行寿命的机理不明确,影响其合理使用。建议今后从以下3个方面开展进一步研究: (1)明确LID设施填料在运行期间理化性质的动态演变过程,发展基于LID设施水量调控和污染物净化效果的新方法;(2)揭示填料入渗性能和污染物吸附量随运行时间尺度的变化规律,从径流水质、材料两个方面探索海绵城市集中入渗条件下,LID设施不同填料发生堵塞和污染物吸附饱和的内在机理及驱动因子;(3)阐明LID设施运行效能衰减机制,建立LID设施运行效能衰减评价方法,进一步研究并确定LID设施合理的使用寿命。     

Model description of storage and infiltration functions of infiltration facilities for urban runoff analysis by a distributed model.

Although there have been simulation researches focusing on reduction of stormwater peak flow by introduced infiltration facilities, model simulation of dynamic runoff behavior is still limited for frequently occurring rainfall events with weak intensity. Therefore, dynamic simulation was carried out in two urban drainages with infiltration facilities incorporated with a distributed model using two methods for describing functions of infiltration facilities. A method adjusting effective rainfall model gave poor simulation of runoff behavior in light rainfalls. Another method considering dynamic change of storage capacity as well as infiltration rate gave satisfactory estimation of the runoff in both drainages. In addition, assumption of facility clogging improved the agreement between measured and simulated hydrographs in small and medium-sized rainfall. Therefore, the proposed method might be useful for quantifying the secondary effects of the infiltration facilities on groundwater recharge and urban non-point pollutant trapping as well as runoff reduction.     

运用温度示踪法确定稳定入渗补给速率

开展不同水位埋深条件下的地中渗透仪入渗实验,分析包气带温度场变化规律及其控制因素,进而采用多层介质热传导解析方程评价入渗补给速率,探讨了温度示踪法评价包气带入渗补给问题的适用性。结果表明:气温控制包气带温度场整体特征,其对温度场的影响随深度增加逐渐减弱。水位埋深影响土壤含水率,控制包气带介质比热,决定了温度场波动性。灌水改变介质热导率从而影响包气带温度场;灌水量小且灌水温差小,灌水本身的热状态对温度场的影响可以忽略。水位埋深浅时,基于多层介质热传导解析方程的入渗补给速率评价结果更为准确,旱季相对雨季,评价结果准确性整体更高;浅部包气带含水率波动性强是造成评价误差的重要原因,选取更短的评价周期和更深的计算剖面可相对提高评价结果准确性。含水率在时间尺度上的波动是温度示踪法在非饱和带应用的难点及关键。     

气候变化对可可西里盐湖流域湖泊水量变化的影响分析

湖泊是气候变化的敏感指示器。为了研究气候变化对湖泊水量的影响,以盐湖流域为研究区,应用统计方法对1989—2018年降雨、气温、蒸发进行线性趋势和突变分析,采用多源卫星遥感技术对湖泊面积等水文要素进行监测,分析湖泊面积与气象要素、湖泊面积与湖泊水量之间的相关性。利用VIC模型模拟径流并结合计算的冰川水量得到盐湖径流组成,定量探讨气象要素对湖泊水量变化的影响,综合分析2011年前后气象要素影响流域湖泊水量的差异。结合统计分析与水文模型定量计算可知:年降雨量、年平均气温显著升高,年蒸发量呈下降趋势,且与湖泊面积有较好的相关性。湖泊面积与湖泊水量间相关性较高,可间接体现气象要素对湖泊水量变化的影响。2011年前卓乃湖和盐湖水量变化主要受降雨量影响,库赛湖和海丁诺尔湖水量变化主要受气温影响;2011—2014年4个湖泊水量变化主要受降雨量影响;2015—2018年4个湖泊水量变化中降雨增加量、冻土释水和地下水补给增加量、冰川融水量对湖泊扩张的贡献约为34.48%、57.66%、7.86%,气温变化成为影响湖泊水量变化的主要因素,降雨量影响次之。