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1.
针对近些年来三江平原大面积发展井灌水稻所导致的地下水位持续下降问题,以853农场为例,采用水量均衡法,测算了853农场2006—2009年维持地下水收支平衡及地下水恢复至适宜埋深条件下的人工回灌量,结果表明:维持地下水收支平衡所需回灌量均小于5 000万m3;地下水恢复至适宜埋深所需回灌量均为2亿m3左右,远远超过维持地下水收支平衡所需回灌量;若继续沿用现状地下水利用模式,未来所需回灌量会更大,建议当地加大地下水资源管理力度。研究成果为853农场乃至整个三江平原地下水资源恢复及可持续利用提供了科学依据。 相似文献
2.
Gerd Wessolek Kai Schwrzel Manfred Renger Robert Sauerbrey Christian Siewert 《植物养料与土壤学杂志》2002,165(4):494-500
A simple model to predict soil water components and the CO2 release for peat soils is presented. It can be used to determine plant water uptake and the CO2 release as a result of peat mineralization for different types of peat soils, various climate conditions, and groundwater levels. The model considers the thickness of the root zone, its hydraulic characteristics (pF, Ku), the groundwater depth and a soil‐specific function to predict the CO2 release as a result of peat mineralization. The latter is a mathematical function considering soil temperature and soil matric potential. It is based on measurements from soil cores at varying temperatures and soil water contents using a respiricond equipment. Data was analyzed using nonlinear multiple regression analysis. As a result, CO2 release equations were gained and incorporated into a soil water simulation model. Groundwater lysimeter measurements were used for model calibration of soil water components, CO2 release was adapted according long‐term lysimeter data of Mundel (1976). Peat soils have a negative water balance for groundwater depth conditions up to 80—100 cm below surface. Results demonstrate the necessity of a high soil water content i.e. shallow groundwater to avoid peat mineralization and soil degradation. CO2 losses increase with the thickness of the rooted soil zone and decreases with the degree of soil degradation. Especially the combination of deep groundwater level and high water balance deficits during the vegetation period leads to tremendous CO2 losses. 相似文献
3.
地下水源热泵系统热平衡模拟三维数值模型 总被引：2，自引：2，他引：0
为了准确模拟预测地下水源热泵系统运行期间的热平衡变化规律特征,避免未来地下水源热泵系统运行期间出现的热贯通现象。以河北省水勘院正定基地地下水源热泵系统示范工程为例,建立了地下水渗流与热量运移三维耦合数值模型,并结合地下水源热泵系统的设计运行方案,预测分析了不同条件下未来地下水源热泵系统的热平衡发展趋势。结果表明,该示范工程按设计方案运行,抽、灌井之间存在热贯通现象。地下水源热泵系统通过增大温差的方法进行调节,可有效地缓解热贯通现象。 相似文献
4.
内蒙古河套灌区灌溉入渗对地下水的补给规律及补给系数 总被引：13，自引：8，他引：5
为准确估计内蒙河套灌区灌溉水入渗补给地下水量,采用试验研究与数值模拟相结合的方法,分别根据灌水前后地下水位变化和土壤含水率变化计算了灌溉水入渗补给地下水系数,并依据土壤水动力学原理,采用数值模拟验证,得到作物生育期灌溉补给地下水系数为0.15,秋浇灌溉补给地下水系数为0.3。河套灌区地下水位埋深相对较浅,通过灌水前后的土壤含水率变化情况和数值模拟结果显示,灌水2～4 d补给地下水量达到最大,8～10 d后即完成对地下水的入渗补给,不同灌水量灌溉水入渗规律基本一致,入渗补给量和入渗时间与灌溉水量直接相关。研究结果将为确定维持灌区生态环境良性发展的引水量阈值提供参考。 相似文献
5.
膜下滴灌灌水量对土壤水热影响及地下水补给耗水响应 总被引：1，自引：1，他引：0
为探求灌水量对棉田地温和生育期地下水补给棉花耗水比例的影响,设置了4种不同膜下滴灌灌水量(3 000,3 750,4 500,5 250m~3/hm~2)进行野外均衡场试验研究。结果表明:灌水量一定时,浅层土壤受气温影响更为显著;同一气象条件下、同一土层地温和土壤有效积温均随灌水量的增加而降低,当灌水量增加75%时,有效积温降低11.3%,同时温度变幅也相对变小;灌水量越大,棉花耗水量及地下水补给作物水量也随之增大。当灌水量从3 000m~3/hm~2增加到5 250m~3/hm~2时,棉花的耗水量增加146.3%,地下水补给比例增加540%,而棉花需水敏感期地下水补给量则增加152.93mm,需水敏感期的地下水补给量最大,但日均地下水补给量随棉花生育期的延长而增大,且各处理的水分利用效率差异不大。此外,在地温较高的夏季高温期(花铃期和吐絮期)以及灌水量较小时,夜间地下水补给作物水量大于或接近白天补给量,说明地温影响地下水的向上补给水量和补给时段。此研究可为合理高效利用农业水资源和优化膜下滴灌棉花灌溉制度提供有效依据。 相似文献
6.
运用化学动力学和水动力学相结合的理论和方法,提取了反映中深层地下水的赋存环境特征、循环速度、资源量组成、可更新能力等方面的重要信息,并以此为依据进行了四平市区中深层地下水资源评价和补给能力分析。研究结果表明,目前四平市区该层地下水已经处于超采状态,四平市区中深层地下水具有补给能力较弱,补给资源有限,水循环滞缓的特点,作为供水水源缺乏保障性。 相似文献
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This paper considers the development of lysimeters and their role in the evolution of our understanding of the dynamics of water and plant nutrients in ecosystems. Lysimeters are delineated volumes of soil. They can be divided into those filled with repacked soil, and those enclosing an undisturbed monolith. The original repacked lysimeter was developed to investigate the concept that all life stems from water, and is considered to be the first quantitative experiment in history. It focussed on the growth of a willow tree and how much of the increment was derived from the soil solids. From this start some 360 years ago lysimeters quickly contributed to the quantification of the transpiration stream and the differentiation of water loss by evaporation from the soil from loss via the leaves of plants. Chronologically, further development began about 210 years ago with the exploration of whether precipitation could account for all the water moving from the land to the oceans, and was the origin of springs. In part, this required a careful quantification of soil evaporation, runoff and deep drainage. This in turn led to the quantification of the soil water balance. As a result, we are able to predict indices, such as crop water use efficiency, drainage and irrigation requirements, contributions to stream flow, groundwater recharge and nutrient loss by leaching. Recognition that the quantification of drainage and leaching required soils of natural structure and profile integrity resulted in the building of the first monolith lysimeter and the development of ‘pan’ or ‘Ebermayer’ lysimeters. Improved technology allowed a better understanding of the role of soil in the regional water balance through the development of small diameter lysimeters that could be transported to a central location subject to the same climatic variables. In contrast, other technological changes allowed the impact of typical soil management operations carried out using regular machinery to be applied on field‐scale lysimeters. The contribution of the different types of lysimeter to the development of our understanding of soil use and management is considered. 相似文献
9.
不同地下水埋深条件下再生水灌溉对冬小麦生长的影响 总被引：10，自引：3，他引：7
为给地下水浅埋区再生水作物安全灌溉提供科学指导,该文利用地中渗透仪控制地下水位,研究不同地下水埋深条件下再生水灌溉对冬小麦生长的影响。结果表明：灌水量相同时,地下水埋深对作物生长影响顺序为:埋深2 m>埋深3 m>埋深4 m;灌水量不同时,地下水埋深为2 m的处理,低水处理较高水处理更能促进冬小麦干物质量和产量的增长;地下水埋深为3 m和4 m时,高水处理较低水处理更能促进冬小麦干物质量和产量的增长。再生水灌溉对冬小麦生长有一定的促进作用。 相似文献
10.
Water and Solute Balances in Recultivated Lignite Mining Dump Soils-Field Data and Lysimeter Experiments 总被引：1，自引：0，他引：1
Knappe S. Haferkorn U. Mattusch J. Meißner R. Rupp H. Wennrich R. 《Water, air, and soil pollution》2004,157(1-4):85-105
Specific problems of water and solute balancing in the central German post-lignite-mining district are caused by the almost unknown interactions between surface water, seepage and groundwater in the unsaturated zone of mining dumps. This paper presents the findings of studies using lysimeter and seepage groundwater measuring systems designed to investigate the water balance and the migration of inorganic components in the vadose zone of recultivated dumps. Despite the heterogeneous tertiary layers of the three lysimeter monoliths studied, the quantity of seepage occurring at a depth of 3 m as well as the evapotranspiration and the soil water regime were almost the same in the 4 years of the investigation. The high variability of the ion balances in seepage reflects inhomogeneities in tertiary dump material and can be explained by substrate properties interacting with the soil's pH. Very high seepage conductivities are caused by coal containing high levels of pyrite with a low pH and high acid potential. These conductivities are caused by comparatively high concentrations of ions of sulphate, iron, aluminium, calcium, magnesium and heavy metals. The results confirm the impact of ventilated and pyrite-containing dump substrates for groundwater quality. 相似文献
11.
Determining soil water‐balance components using an irrigated grass lysimeter in NE Austria 
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下载免费PDF全文 The water balance of a certain soil profile in a certain time interval is subjected to changes of soil water content within the respective profile, and fluxes at its upper and lower boundary. Weighing lysimeters are valuable instruments for water‐balance studies. Typically, mass changes—thus, changes of soil profile water content—are detected by a weighing system, while seepage water outflow is measured by a tipping bucket, and precipitation data originate from a rain gauge. Hence, evapotranspiration as unknown component can be determined by solving a simple water‐balance equation. However, using separately measured precipitation data may cause implausible (negative) evapotranspiration. In this study, change of soil profile water content, seepage water, precipitation, and evapotranspiration were determined directly from 10‐min lysimeter data from 2011. Precipitation measured with the lysimeter was in total 20% greater than rain‐gauge values. Even dew formation was measured and considered as water‐balance component; however, its total amount was rather low. Evapotranspiration calculated on daily and hourly base indicated a sound correlation with measured data, but measured values were considerably smaller. Both calculated and measured dew amount were of the same magnitude. Comparison of lysimeter evapotranspiration with daily calculations (neglecting dew) and hourly computation (considering dew) delivered similar results. Generally, the utilized lysimeter facility and the specific data management provided sound water‐balance components with high accuracy and temporal resolution, respectively. 相似文献
12.
Severin Hohensinner Mathew Herrnegger Alfred P. Blaschke Christine Habereder Gertrud Haidvogl Thomas Hein Mathias Jungwirth Michael Weiβ 《CATENA》2008
River/floodplain restoration programs are often based on type-specific reference conditions of the respective river section. Most large rivers in the industrialized world are heavily degraded and lack near-natural reference sites. For that reason, historical analyses of the pre-channelization state have been used to define adequate restoration targets at the Austrian Danube section in the Alluvial Zone National Park downstream from Vienna. This study compares new reference data derived from 3D-reconstructions in the form of digital terrain models from two historical Danube river landscapes: the Machland floodplain in 1812 and the former floodplain in Vienna in 1849. The focus is on the original hydrological surface and subsurface connectivity of the river-floodplain systems related to different flow situations. Here, we use water cover, shorelines, depth of the groundwater table and inundation depth as surrogates for measuring connectivity. The results show that the two study sites naturally constituted extreme formations of the Austrian anabranching Danube sections. The Machland section was one of the narrowest floodplains but highly dynamic, and the Vienna/Lobau section was one of the broadest, whereby only the central part close to the main channel originally showed high morphological turnover. The analyses of hydrological surface connectivity relative to total floodplain extension reveal significant differences due to their basic geological and geographical conditions. Despite these basic differences, both study sites – in absolute numbers – showed similar extensions of the water bodies at low and mean flow. The depths of the groundwater table related to mean flow were also comparable. Prior to channelization, the groundwater conditions in both floodplains favored the formation of wet to moist alluvial forest communities. 相似文献
13.
Future climate changes might have some impacts on the discharge regime of rivers in Germany regarding, e.g., longer low‐flow periods in summer months due to a decreased precipitation and increased evapotranspiration. During such low‐flow periods, water temperature increases leading to a reduced oxygen concentration and a decrease in water quality. An assessment of such impacts is required to derive adaptation strategies for future water‐resources management. The main objective of our study was to obtain an estimation of the impact of projected future climate change on evapotranspiration, groundwater recharge, and low‐flow conditions. For that purpose, we applied a hydrological catchment model in the Ucker catchment with an area of 2415 km2 located in the lowlands of NE Germany using meteorological time series from 1951 to 2055. These time series were generated by the Potsdam Institute of Climate Impact Research based on the A1B‐Scenario with an increase of 1.4°C of the mean annual temperature and a mean decrease of 8% in annual rates of precipitation. After model calibration, the comparison of simulated and observed daily discharge rates from 1989 to 2003 led to a Nash‐Sutcliffe‐Index NS = 0.63. The results of this simulation study indicated that the amount of days with low‐flow conditions in the Ucker river will increase and groundwater recharge especially at forested areas will decrease in an order of magnitude of 1%–94%. 相似文献
14.
为揭示干旱区地下水补排量演变规律及其与坎儿井流量衰减的关系,通过梳理1949年以来鄯善县水资源开发利用、地下水资源调查评价资料,分析了地下水补排量的变化,划分地下水补排量演化的阶段。利用双变量相关分析法,分析了地下水主要补排量演化与坎儿井流量衰减之间的关系,并分析了其原因。结果表明：1）鄯善县地下水补排量的变化主要受人类活动影响,气候变化的影响微弱,且主要补排量变化的突变点与国家实施改革开放、西部大开发等政策的起始点相一致,政策是人为因素中的关键因素;2）坎儿井出流量与河道渗漏补给量、渠道渗漏补给量、田间入渗补给量、机井地下水开采量之间的相关系数依次为0.312、?0.327、?0.574、?0.959,说明坎儿井流量的衰减主要受机井开采地下水影响,其次为田间入渗补给量,河道和渠道（干支渠）渗漏补给影响较小;3）坎儿井出流量与地下水补排量的响应关系主要由其空间分布位置决定。该研究对坎儿井保护和超采区治理提供参考。 相似文献
15.
Manfred Renger Gerd Wessolek Kai Schwrzel Robert Sauerbrey Christian Siewert 《植物养料与土壤学杂志》2002,165(4):487-493
An extended water regime model was used for calculating the evapotranspiration, groundwater recharge, and peat mineralization (CO2 and N release) for various fen locations with grassland utilization in dependence on the groundwater level. The results show that an increasing groundwater level leads to a strong decline of the actual evapotranspiration Et. For example, increasing the groundwater level from 30 to 120 cm diminishes the Et by up to 230 mm a—1. A positive groundwater recharge only takes place at groundwater levels of 90 cm and more. At smaller distances the capillary rise into the rooting zone during the summer months is greater than the water seepage during the winter months, so that a negative groundwater recharge‐balance is reached in the course of a year. The CO2‐ and the N‐release, as well as the annual decline in peat thickness, increase significantly with rising groundwater levels. The results show, that varying the groundwater level can influence the water regime and the peat mineralization significantly. The lower the groundwater level the less is the peat decomposition. The demand for a groundwater level as small as possible is, however, limited by an agricultural utilization of the fens. Choosing the optimum groundwater level should consider the aims (1) peat mineralization, (2) gas emission (CO2, CH4, N2O), and (3) crop production. If a grassland utilization is supposed to be made possible and all three aims above are given equal importance, the groundwater level should be maintained at 30 cm. At this distance, about 90 % of the optimum plant output can be reached. The peat mineralization can be reduced to 30 to 40 % of the maximum peat mineralization. The gas emission amounts to 50—60 % of the maximum value. 相似文献
16.
伴随城市化进程和产业结构调整,我国出现许多污染场地亟待修复。通过某典型有机氯农药污染场地抽水试验论证抽出-处理修复方案应用于该污染场地地下水修复的可行性及获取抽出-处理工程设计所需要的参数,同时监测了特征污染物的浓度变化特征。该污染场地的地下水渗透系数为8.03 m·d-1,抽水井影响半径为117.1 m,长期抽水试验获得的单口井抽水量不低于170 m3·d-1,回灌速度达到7 m3·h-1。结果表明：该污染场地实施抽水是可行的,地下水量满足后续抽出-处理修复工程,可通过自来水回灌减缓修复过程抽水量下降趋势,但此过程也影响地下水的流动方向。同时,抽水过程可抽出大量的污染物,越靠近污染区域,抽提污染物的效果越明显;随着抽水的进行,污染物的浓度总体显现降低的趋势。此外,自来水回灌可稀释地下水中的污染物。 相似文献
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为了研究地表水与地下水不同补给关系下硝酸盐氮在傍河农田的迁移规律,选取大沽河河床沙样作为沙槽试验介质,设计地表水与地下水相互补给装置,模拟无补给、地表水补给地下水和地下水补给地表水3种方式下硝酸盐氮在土壤中的迁移,通过测定各取样点硝酸盐氮含量和到达时间,分析了其迁移规律。结果表明:纯淋洗实验中,淋洗强度与沙样颗粒越小,硝酸盐氮在表层沙中的累积越明显,硝酸盐氮的迁移也越慢。地表水与地下水相互补给试验中,补给水位上升,硝酸盐氮的积累量增加、迁移到饱水带的时间缩短;补给水力坡度为0.5时,硝酸盐氮在细沙饱水带中迁移速度约为5.3 cm/min;水力坡度变为0.7时,迁移速度约为9.4 cm/min;补给水力坡度为0.5时,硝酸盐氮在中沙饱水带的迁移速度约为12.3 cm/min。硝酸盐氮在包气带中的积累量随着沙层深度的增加而减少;淋洗强度、水力坡度及沙样颗粒越大,硝酸盐氮在包气带和饱水带中的迁移速度越快;补给水位越高,硝酸盐氮迁移至饱水带的时间越短。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(13-14):2053-2067
Abstract: Ammonium‐nitrogen (N) and nitrate‐N concentrations in groundwater were monitored at three farming villages in northern Vietnam during 2002 and 2006 with 6‐month intervals, where 380 to 420 kg/ha of chemical fertilizer N have been applied annually. With reference to the δ15N value, the source of N in the groundwater was identified as chemical fertilizer in the two villages and as animal waste and chemical fertilizer in the one village where animal waste fertilizer had been applied additionally. Ammonium‐N concentration was alarmingly higher than the drinking water standards, whereas the nitrate‐N concentration was lower. These concentrations did not increase over time. The effect of the natural groundwater recharge diluting the concentrations was considered as a potential reason, and such trends are expected to continue. Spatial variation in the ammonium‐N and nitrate‐N concentrations was recognized as being due to differences in the applied amount and the source of fertilizer N, respectively. 相似文献
19.
该文以季节性冻融灌区内蒙古河套灌区为研究对象,建立灌区冻融期地下水补排模型,与三维地下水数值模型相结合,构建适用于季节性冻融灌区的生育期-冻融期全周年地下水动态模拟模型。采用河套灌区2006—2013年灌区实测地下水埋深对模型进行了率定和验证,并针对河套灌区不同地下水矿化度可开采区(分别为2.0、2.5及3.0g/L)、不同渠井结合比设置了18种井渠结合节水情景,对其地下水动态进行了预测。结果表明,该文构建的冻融期模型能准确反映其地下水动态过程;井渠结合后地下水埋深变化与井渠结合区地下水开采利用的矿化度上限和渠井结合比有关,井渠结合区地下水矿化度上限越大,渠井结合比越小,地下水埋深增加越多;实施井渠结合后,灌区生育期平均地下水埋深增加0.103~0.445 m,秋浇期增加0.076~0.243 m,冻融期增加0.096~0.216 m;从空间上看,全灌区年均地下水埋深增加0.096~0.316 m,井渠结合区增加0.346~0.635 m,非井渠结合区变化较少,一般不足7 cm。该文为季节性冻融灌区开展大规模井渠结合灌溉提供参考。 相似文献
20.
Two soil–water balance models were tested by a comparison of simulated with measured daily rates of actual evapotranspiration, soil water storage, groundwater recharge, and capillary rise. These rates were obtained from twelve weighable lysimeters with three different soils and two different lower boundary conditions for the time period from January 1, 1996 to December 31, 1998. In that period, grass vegetation was grown on all lysimeters. These lysimeters are located in Berlin‐Dahlem, Germany. One model calculated the soil water balance using the Richards equation. The other one used a capacitance approach. Both models used the same modified Penman formula for the estimation of potential evapotranspiration and the same simple empirical vegetation model for the calculation of transpiration, interception, and evaporation. The comparisons of simulated with measured model outputs were analyzed using the modeling‐efficiency index IA and the root mean squared error RMSE. At some lysimeters, the uncalibrated application of both models led to an underestimation of cumulative and annual rates of groundwater recharge and capillary rise, despite a good simulation quality in terms of IA and RMSE. A calibration of soil‐hydraulic and vegetation parameters such as maximum rooting depth resulted in a better fit between simulated and observed cumulative and annual rates of groundwater recharge and capillary rise, but in some cases also decreased the simulation quality of both models in terms of IA and RMSE. The results of this calibration indicated that, in addition to a precise determination of the soil water‐retention functions, vegetation parameters such as rooting depth should also be observed. Without such information, the rooting depth is a calibration parameter. However, in some cases, the uncalibrated application of both models also led to an acceptable fit between measured and simulated model outputs. 相似文献