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Wenling Chen Jianjun Wang Yanfeng Liu Menggui Jin Xing Liang Zaimin Wang Ty P. A. Ferré 《水文研究》2021,35(7):e14290
Accurate estimation of groundwater recharge (GR) and evapotranspiration (ET) are essential for sustainable management of groundwater resources, especially in arid and semi-arid regions. In the Manas River Basin (MRB), water shortage is the main factor restricting sustainable development of irrigated agriculture, which relies heavily on groundwater. Film-mulched drip irrigation significantly changes the pattern and dominant processes of water flow in the unsaturated zone, which increases the difficulty of GR and ET estimation. To better estimate GR and ET under film-mulched drip irrigation in the MRB, bromide tracer tests and soil lithologic investigation were conducted at 12 representative sites. A one-dimensional variably saturated flow model (HYDRUS-1D) was calibrated at each site using soil evaporation data inferred from the bromide tracer tests. The results showed that average annual soil evaporation in uncultivated lands calculated from bromide trace tests was 25.55 mm. The annual GR ranged from 5.5 to 37.0 mm under film-mulched drip irrigation. The annual ET ranged from 507.0 to 747.1 mm, with soil evaporation between 35.7 and 117.0 mm and transpiration between 460.9 and 642.3 mm. Soil evaporation represented 7% to 16% of the total ET and more than 70% of precipitation and irrigation water was used by cotton plants. Spatial variations of soil lithology, water table depth and initial soil water content led to the spatial differences of GR and ET in the MRB. Our study indicated that bromide tracer tests are useful for inferring ET in the arid and semi-arid oases. The combination of bromide tracer tests and HYDRUS-1D enhances reliability for estimation of GR and ET under film-mulched drip irrigation in the MRB and shows promise for other similar arid inland basins around the world. 相似文献
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Reference evapotranspiration (ET0) is an important element in the water cycle that integrates atmospheric demands and surface conditions, and analysis of changes in ET0 is of great significance for understanding climate change and its impacts on hydrology. As ET0 is an integrated effect of climate variables, increases in air temperature should lead to increases in ET0. However, this effect could be offset by decreases in vapor pressure deficit, wind speed, and solar radiation which lead to the decrease in ET0. In this study, trends in the Penman–Monteith ET0 at 80 meteorological stations during 1960–2010 in the driest region of China (Northwest China) were examined. The results show that there was a change point for ET0 series around the year 1993 based on the Pettitt's test. For the region average, ET0 decreased from 1960 to 1993 by ?2.34 mm yr?2, while ET0 began to increase since 1994 by 4.80 mm yr?2. A differential equation method based on the Food and Agriculture Organization Penman–Monteith formula was used to attribute the change in ET0. The attribution results show that the significant decrease in wind speed dominated the change in ET0, which offset the effect of increasing air temperature and led to the decrease in ET0 from 1960 to 1993. However, wind speed began to increase, and the amplitude of increase in air temperature also rose significantly since the mid‐1990s. Increases in air temperature and wind speed together reversed the trend in ET0 and led to the increase in ET0 since 1994. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Calligonum mongolicum is often planted as a windbreak and for sand stabilization on mobile and semi-mobile sand dunes in extremely arid regions. However, water availability remains a key limiting factor for its survival and population expansion, and water use strategies and responses to precipitation events of this species are unknown. Here, we determined water use strategy of C. mongolicum under extreme arid conditions by measuring the oxygen stable isotopes (δD and δ18O) in xylem water and in potential water sources (precipitation, soil water, and groundwater). We used the IsoSource model to determine the relative contributions of different water sources to water utilization by C. mongolicum. Our results showed that: (1) water sources used by C. mongolicum exhibited seasonal variability, with shallow soil water accounting for 42% of utilization during early spring (April), and deep soil water and groundwater being predominantly used during the summer and autumn and accounting for 61%–84% of utilization, (2) C. mongolicum did not respond to small precipitation events, but responded significantly to large precipitation events. C. mongolicum maintained the utilization of soil water in all layers at 74%–81% of deep soil water and groundwater before a 5.8 mm precipitation event. A precipitation event of 18.8 mm increased the contribution of surface water from 4% before to 17% after precipitation, indicating that C. mongolicum has a strong capacity for self-regulation and adaptation; namely, C. mongolicum is capable of developing an optimal phenotype through self-regulation, thereby maximizing water acquisition. 相似文献
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As a critical water discharge term in basin‐scale water balance, accurate estimation of evapotranspiration (ET) is therefore important for sustainable water resources management. The understanding of the relationship between ET and groundwater storage change can improve our knowledge on the hydrological cycle in such regions with intensive agricultural land usage. Since the 1960s, the North China Plain (NCP) has experienced groundwater depletion because of overexploitation of groundwater for agriculture and urban development. Using meteorological data from 23 stations, the complementary relationship areal evapotranspiration model is evaluated against estimates of ET derived from regional water balance in the NCP during the period 1993–2008. The discrepancies between calculated ET and that derived by basin water balance indicate seasonal and interannual variations in model parameters. The monthly actual ET variations during the period from 1960 to 2008 are investigated by the calibrated model and then are used to derive groundwater storage change. The estimated actual ET is positively correlated with precipitation, and the general higher ET than precipitation indicates the contributions of groundwater irrigation to the total water supply. The long term decreasing trend in the actual ET can be explained by declining in precipitation, sunshine duration and wind speed. Over the past ~50 years, the calculated average annual water storage change, represented by the difference between actual ET and precipitation, was approximately 36 mm, or 4.8 km3; and the cumulative groundwater storage depletion was approximately 1700 mm, or 220 km3 in the NCP. The significantly groundwater storage depletion conversely affects the seasonal and interannual variations of ET. Irrigation especially during spring cause a marked increase in seasonal ET, whereas the rapid increasing of agricultural coverage over the NCP reduces the annual ET and is the primary control factor of the strong linear relationship between actual and potential ET. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Thomas R. Cianciolo Jacob S. Diamond Daniel L. McLaughlin Robert A. Slesak Anthony W. D'Amato Brian J. Palik 《水文研究》2021,35(4):e14014
Black ash (Fraxinus nigra) wetlands are widespread, forested landscape features in the western Great Lakes region. However, the future of these ecosystems is threatened due to impending spread of the invasive emerald ash borer (EAB), which results in tree mortality, decreased transpiration, and potential shifts to wetter, non-forested conditions. The vulnerability to such ecohydrologic shifts likely varies according to local hydrologic regimes controlled by landscape settings, but this site-dependent vulnerability and our ability to predict it is unknown. Here, we assessed vulnerability potential as a function of site hydrology in 15 undisturbed black ash wetlands from their three most common hydrogeomorphic settings in northern Minnesota: lowland, depression, and transition. Further, we used high-resolution (1-cm) surface elevation models to assess spatial variability of water levels at a subset of 10 sites. Although we observed similar ET and groundwater exchange rates among settings, lowland sites were generally drier because of elevated landscape position and greater water level drawdowns (via lower specific yield). We predict that such drier sites will exhibit greater water level increases following EAB-induced ash mortality, compared to wetter sites where open water evaporation and shallow-rooted understory transpiration will offset losses in tree transpiration. Moreover, compared to wetter sites, drier sites exhibited minimal microtopographic variation, limiting the number of elevated microsites for tree establishment and eventual canopy recovery after ash loss. These results suggest that site wetness is a simple and effective predictor of black ash wetland vulnerability to hydrologic regime change. To that end, we assessed the ability of common terrain metrics to predict site wetness, providing a potential tool to target vulnerable areas for active management efforts. 相似文献
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甘肃省河西地区高层建筑动力特性脉动观测研究 总被引：1，自引：1，他引：0
采用脉动观测方法对甘肃省河西地区的武威皇台大厦,张掖电力大厦和张掖国税大厦３栋高层建设的自振特性进行测试。在分析３栋建筑的自振周期、振型和阻尼比时,结合对当地场地特性的分析,指出了河西地区对高层建设有利的场地条件以及今后在该地区修建以建筑时应注意的若干问题。 相似文献
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高台陡坎从５０年期就被中外地学者关注,对其成因持有两种观点：一种观点认为高台陡坎属于新构造运动与地震事件的产物;另一种观点认为它属于非新构造运动,是人工堆筑的产物。高台陡坎经由东到西方向的地震地质追索调查,确定了其延伸方向、展布范围与规模,描述了结构与构造及物质成分等特征。结合槽探工程揭露脸证、跨陡坎电测深基底等深线剖面成果解释、地震事件的考察与研究以及民国新纂高台县志（卷二与卷三）上的历史记载考 相似文献
9.
In the Manas River basin (MRB), groundwater salinization has become a major concern, impeding groundwater use considerably. Isotopic and hydrogeochemical characteristics of 73 groundwater and 11 surface water samples from the basin were analysed to determine the salinization process and potential sources of salinity. Groundwater salinity ranged from 0.2 to 11.91 g/L, and high salinities were generally located in the discharge area, arable land irrigated by groundwater, and depression cone area. The quantitative contributions of the evaporation effect were calculated, and the various groundwater contributions of transpiration, mineral dissolution, and agricultural irrigation were identified using hydrogeochemical diagrams and δD and δ18O compositions of the groundwater and surface water samples. The average evaporation contribution ratios to salinity were 5.87% and 32.7% in groundwater and surface water, respectively. From the piedmont plain to the desert plain, the average groundwater loss by evaporation increased from 7% to 29%. However, the increases in salinity by evaporation were small according to the deuterium excess signals. Mineral dissolution, transpiration, and agricultural irrigation activities were the major causes of groundwater salinization. Isotopic information revealed that river leakage quickly infiltrated into aquifers in the piedmont area with weak evaporation effects. The recharge water interacted with the sediments and dissolved minerals and subsequently increased the salinity along the flow path. In the irrigation land, shallow groundwater salinity and Cl? concentrations increased but not δ18O, suggesting that both the leaching of soil salts due to irrigation and transpiration effect dominated in controlling the hydrogeochemistry. Depleted δ18O and high Cl? concentrations in the middle and deep groundwater revealed the combined effects of mixing with paleo‐water and mineral dissolution with a long residence time. These results could contribute to the management of groundwater sources and future utilization programs in the MRB and similar areas. 相似文献
10.
Yin‐Phan Tsang George Hornberger Louis A. Kaplan J. Denis Newbold Anthony K. Aufdenkampe 《水文研究》2014,28(4):2439-2450
Evapotranspiration (ET) plays a crucial role in catchment water budgets, typically accounting for more than 50% of annual precipitation falling within temperate deciduous forests. Groundwater ET is a portion of total ET that occurs where plant roots extend to the capillary fringe above the phreatic surface or induce upward movement of water from the water table by hydraulic redistribution. Groundwater ET is spatially restricted to riparian zones or other areas where the groundwater is accessible to plants. Due to the difficulty in measuring groundwater ET, it is rarely incorporated explicitly into hydrological models. In this study, we calibrated Topographic Model (TOPMODEL) using a 14‐year hydrograph record and added a groundwater ET pathway to derive a new model, Groundwater Evapotranspiration TOPMODEL (GETTOP). We inspected groundwater elevations and stream flow hydrographs for evidence of groundwater ET, examined the relationship between groundwater ET and topography, and delineated the area where groundwater ET is likely to take place. The total groundwater ET flux was estimated using a hydrological model. Groundwater ET was larger where the topography was flat and the groundwater table was shallow, occurring within about 10% of the area in a headwater catchment and accounting for 6 to 18% of total annual ET. The addition of groundwater ET to GETTOP improved the simulation of stream discharge and more closely balanced the watershed water budget. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
11.
The White method is a simple but the most frequently applied approach to estimate groundwater evapotranspiration (ETg) from groundwater level diurnal signals. Because of a lack of direct measurements of ETg, it is difficult to evaluate the performance of the White method, particularly in field environments with variable groundwater fluctuations. A 2‐year field observation in a hyper‐arid riparian tamarisk (Tamarix spp.) stand with deep groundwater depth in the lower Tarim River basin of China was conducted to measure the surface evapotranspiration (ETs) and groundwater table. The performance of the White method and the influences of the variable groundwater fluctuations on the determinations of the specific yield (Sy) and recharge rate of groundwater (r) in the White method were investigated. The results showed that the readily available Sy determined by Loheide's method was feasible but must be finely determined based on the soil textures in the layers in which the groundwater level fluctuated. A constant Sy value for a defined porous medium could be assumed regardless of the discharge or recharge processes of groundwater. The time span of 0000 h to 0600 h for r estimation for the White method worked best than other time spans. A 2‐day moving average of r values further enhance ETg estimation. Slight effects of environmental or anthropogenic disturbances on the diurnal fluctuations of groundwater level did not influence the ETg estimations by the White method. Our results provide valuable references to the application of the White method for estimating daily ETg in desert riparian forests with deep groundwater depth. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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地下水动态的异常变化既有可能是地震前兆异常信息,也有可能是某种环境干扰所引起,如降雨和地下水开采等.如何及时识别并排除环境干扰,对于成功判定地震前兆异常至关重要.云南姚安井水位于2009年10月后出现了下降趋势的异常变化,截止2011年底,最大下降幅度达3m.为分析该井水位异常变化的形成原因,依据姚安井水文地质环境特征,建立了相关的数学物理模型,定量分析了降水量和地下水开采量对该井水位的影响.分析结果表明,姚安井2009年后出现的水位大幅下降可能与区域降水量减小导致的地下水开采活动增强有一定的相关性.文中所采取的异常识别与分析方法,对今后地下水动态异常识别及前兆信息判定工作具有一定的借鉴意义. 相似文献
14.
Shallow groundwater plays a key role in agro‐hydrological processes of arid areas. Groundwater often supplies a necessary part of the water requirement of crops and surrounding native vegetation, such as groundwater‐dependent ecosystems. However, the impact of water‐saving irrigation on cropland water balance, such as the contribution of shallow groundwater to field evapotranspiration, requires further investigation. Increased understanding of quantitative evaluation of field‐scale water productivity under different irrigation methods aids policy and decision‐making. In this study, high‐resolution water table depth and soil water content in field maize were monitored under conditions of flood irrigation (FI) and drip irrigation (DI), respectively. Groundwater evapotranspiration (ETg) was estimated by the combination of the water table fluctuation method and an empirical groundwater–soil–atmosphere continuum model. The results indicate that daily ETg at different growth stages varies under the two irrigation methods. Between two consecutive irrigation events of the FI site, daily ETg rate increases from zero to greater than that of the DI site. Maize under DI steadily consumes more groundwater than FI, accounting for 16.4% and 14.5% of ETa, respectively. Overall, FI recharges groundwater, whereas DI extracts water from shallow groundwater. The yield under DI increases compared with that under FI, with less ETa (526 mm) compared with FI (578 mm), and irrigation water productivity improves from 3.51 kg m?3 (FI) to 4.58 kg m?3 (DI) through reducing deep drainage and soil evaporation by DI. These results highlight the critical role of irrigation method and groundwater on crop water consumption and productivity. This study provides important information to aid the development of agricultural irrigation schemes in arid areas with shallow groundwater. 相似文献
15.
降水条件下的典型干旱区陆面特征模拟验证 总被引：6，自引：0，他引：6
利用“我国西北干旱区陆－气相互作用观测试验\"在敦煌双墩子戈壁站取得的观测资料及最近的一些研究成果对陆面模式中反照率、相似性函数及地表粗糙度(动量粗糙度,标量粗糙度)3个方面的参数化方案进行了改进,然后对一次典型降水过程的陆面特征及近地层的风、温、湿进行了模拟.结果表明：改进的模式能对降水条件下的干旱区陆面特征进行较好的模拟,其中对辐射、地表温度的模拟相当好,而对能量的模拟虽然还有要改进的地方,但总体结果令人满意;另外改进后的模式对近地层的温度和湿度的模拟也有明显的改善. 相似文献
16.
云南姚安井2009年10月后水位下降的成因分析 总被引：1，自引：0，他引：1
地下水动态的异常变化既有可能是地震前兆异常信息, 也有可能是某种环境干扰所引起, 如降雨和地下水开采等. 如何及时识别并排除环境干扰, 对于成功判定地震前兆异常至关重要. 云南姚安井水位于2009年10月后出现了下降趋势的异常变化, 截止2011年底, 最大下降幅度达3 m. 为分析该井水位异常变化的形成原因, 依据姚安井水文地质环境特征, 建立了相关的数学物理模型, 定量分析了降水量和地下水开采量对该井水位的影响. 分析结果表明, 姚安井2009年后出现的水位大幅下降可能与区域降水量减小导致的地下水开采活动增强有一定的相关性. 文中所采取的异常识别与分析方法, 对今后地下水动态异常识别及前兆信息判定工作具有一定的借鉴意义. 相似文献
18.
The Fodongmiao-Hongyazi Fault belongs to the forward thrust fault of the middle segment of northern Qilian Shan overthrust fault zone, and it is also the boundary between the Qilian Shan and Jiudong Basin. Accurately-constrained fault slip rate is crucial for understanding the present-day tectonic deformation mechanism and regional seismic hazard in Tibet plateau. In this paper, we focus on the Shiyangjuan site in the western section of the fault and the Fenglehe site in the middle part of the fault. Combining geomorphic mapping, topographic surveys of the deformed terrace surfaces, optically stimulated luminescence (OSL) dating, terrestrial cosmogenic nuclide dating and radiocarbon (14C) dating methods, we obtained the average vertical slip rate and shortening rate of the fault, which are ~1.1mm/a and 0.9~1.3mm/a, respectively. In addition, decadal GPS velocity profile across the Qilian Shan and Jiudong Basin shows a basin shortening rate of~1.4mm/a, which is consistent with geological shortening rates. Blind fault or other structural deformation in the Jiudong Basin may accommodate part of crustal shortening. Overall crustal shortening rate of the Jiudong Basin accounts for about 1/5 of shortening rate of the Qilian Shan. The seismic activity of the forward thrust zone of Tibetan plateau propagating northeastward is still high. 相似文献
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本文将Ｓ．Ｐａｒｋ１９８４年提出的解决三维大地电磁测深问题的薄层近似方法,用于甘肃省河西地区的大地电磁测深定点复测结果的资料解释,展示了这种方法应用于复杂介质结构下的大地电磁测深工作的良好前景。依据该方法理论而编制的程序有较高的计算精度。 相似文献
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Canopy interception is one of the most important processes in an ecosystem, but it is still neglected when assessing evapotranspiration (ET) partitioning in apple orchards on the Loess Plateau in China. To explore the importance of canopy interception, we monitored two neighbouring apple orchards on the Loess Plateau in China, one 8‐year‐old and the other 18‐years old at the start of the study, from May to September for four consecutive years (2013–2016). We measured parameters of canopy interception (I) including precipitation, throughfall, stemflow, leaf area index, transpiration (T), and soil evaporation (S) to quantify ET. The importance of canopy interception was then assessed by comparing the relationship between water supply (precipitation) and water demand (ET), calculated with and without considering canopy interception (T + S and T + S + I, respectively). Tree age clearly influenced canopy interception, as estimates of annual canopy interception during the study years in the younger and older orchards amounted to 22.2–29.4 mm and 26.8–39.9 mm, respectively. Daily incident rainfall and rainfall intensity in both orchards were significantly positively correlated with daily canopy interception in each year. The relationship between annual precipitation and annual ET (calculated with and without consideration of canopy interception) in the younger orchard differed during 2015 and 2016. Ignoring canopy interception would result in underestimation of annual ET in both apple orchards and hence incorrect evaluation of the relationship between water supply and water demand, particularly for the younger orchard during 2015 and 2016. Thus, for a complete understanding of water consumption in apple orchards in this and similar regions, canopy interception should not be ignored when assessing ET partitioning. 相似文献