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1.
Yinchuan Basin, a semi‐arid area located in Northwest China, is currently subject to increasing pressure from the altered hydrology due to the anthropogenic activities as well as increasing water demands for regional development. Sustainable water management across the region must be underpinned by a clear understanding of the factors that constrain water supply in this area. We measured the stable isotope of oxygen and hydrogen to determine the likely processes that control the interrelations among precipitation, surface water (Yellow River), and groundwater. The hydrogen and oxygen values demonstrate that 2 primary hydrochemical processes, mixing and evaporation/condensation, occurred in the Basin. Recharge proportions of precipitation and Yellow River were quantitatively evaluated based on the isotope mass balance method. The proportions of the Yellow River and atmospheric precipitation recharge are 87.7% and 12.3%, respectively. The evaporation proportions calculated with 18O and D by Rayleigh fractional equation are close to each other, which demonstrate that evaporation intensity increases following the flow direction of the Yellow River. The findings obtained in this study are useful for recognizing the significance of Yellow River to Yinchuan Basin, and some optimal allocation schemes can be adopted for a prospective development of this reputed area in Northwest China.  相似文献   

2.
水是人类生存之源,而湖荡被称为地球之“肾”,是河湖水系连接的关键缓冲节点,与人类生存和发展息息相关。长三角平原水系众多,河流纵横,天然湖泊与人工沟渠遍布,平原湖荡湖水与周边地下水的水力联系较为频繁,而地下水对湖泊水均衡贡献尚不明确,对平原湖荡地下水赋存和运移规律的认识不足。本研究以苏州吴江区元荡湖为研究对象,选取氡同位素作为湖水和地下水水力交换过程的示踪剂,建立氡箱模型,揭示元荡湖不同区段与地下水的水力联系过程和补给关系,并通过水位动态验证分析湖水—地下水交互关系。枯水期元荡湖水位和氡浓度空间分布特征指示研究区内地下水向湖水排泄,其中以湖泊西侧较为明显,地下水入流补给的氡为7.137×106 Bq/d,输入量源项占比为90%,地下水流入量为4540.801 m3/d,地下水每日流入量对元荡湖水量的贡献率为2.551%。参数敏感性分析结果表明,风速与地下水222Rn活度为特别敏感参数,取值差异较大时会导致计算误差急剧增大,改善测点布置和提高模型参数精度能有效提高模型计算结果的准确性和可靠程度。借助氡同位素示踪方法,建立湖泊氡箱模型,是研究平原湖荡内地下水补、径、排特征的有效方法。本研究在一定程度上加深了对平原湖荡区域水量均衡的认识,有助于了解平原湖荡水均衡和水循环机制,为平原湖荡水资源开发利用与环境保护提供数据支撑。  相似文献   

3.
Groundwater recharge and discharge in the Akesu alluvial plain were estimated using a water balance method. The Akesu alluvial plain (4842 km2) is an oasis located in the hyperarid Tarim River basin of central Asia. The land along the Akesu River has a long history of agricultural development and the irrigation area is highly dependent on water withdrawals from the river. We present a water balance methodology to describe (a) surface water and groundwater interaction and (b) groundwater interaction between irrigated and non‐irrigated areas. Groundwater is recharged from the irrigation system and discharged in the non‐irrigated area. Uncultivated vegetation and wetlands are supplied from groundwater in the hyperarid environment. Results show that about 90% of groundwater recharge came from canal loss and field infiltration. The groundwater flow from irrigated to non‐irrigated areas was about 70% of non‐irrigated area recharge and acted as subsurface drainage for the irrigation area. This desalinated the irrigation area and supplied water to the non‐irrigated area. Salt moved to the non‐irrigation area following subsurface drainage. We conclude that the flooding of the Akesu River is a supplemental groundwater replenishment mechanism: the river desalinates the alluvial plain by recharging fresh water in summer and draining saline regeneration water in winter. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

4.
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   

5.
ABSTRACT

Water quality in the arid regions has long been an issue of great concern in the world. In this study, quantitative research was carried out to create new knowledge to understand the processes that determine the variation in the groundwater chemical composition of the Yinchuan Plain, China. In this context, the distribution and zonation characteristics of groundwater in this area were assessed using geochemical modelling of groundwater quality evolution. The results show the existence of an obvious zonation from the recharge area to the discharge area in the study area. Dominant anions transform from HCO3 in the inclined pluvial area to HCO3·SO4·Cl in the discharge region, while the main cations vary from Ca and Mg to Na and Mg. The simulation results indicate that the evaporation process triggers 2–35% of groundwater loss, leading to an increase in the total dissolved solids. The irrigation leakage mixes with the groundwater at about 8:2, suggesting that the irrigation leakage dilutes the groundwater.  相似文献   

6.
流域范围内地表水和地下水转化对盐湖成盐元素的运移和富集具有十分重要的意义.本文通过尕斯库勒盐湖盆地内流域水体的水化学和B同位素特征识别了地表水和地下水之间的定量转化关系,在此基础上估算了流域中铀的补给通量.结果表明,流域水体中离子的分异除了蒸发浓缩作用之外,还受重力分异及掺杂作用的影响;上游库拉木勒克萨伊河和阿特阿特坎河水体在出山口附近转入地下并在中游补给地表水和地下水,其补给率分别占48.8%和51.2%,年均补给量分别为1.08×108和1.13×108m3/a;在中游至尾闾盐湖段,阿拉尔河和侧向补给对盐湖卤水的补给率占55.2%,深部水体的补给占44.8%;至少从5.7 ka以来,上游水体对盐湖卤水中铀的补给通量为4.11×103t,在湖积平原黏土沉积带以及祁漫塔格山前局部还原带可能具有较大规模的铀矿.研究结果有助于建立盐湖盆地水循环模式、揭示卤水资源形成机制;同时为尕斯库勒盐湖盆地水资源的高效利用和寻找铀矿提供理论依据和技术支持.  相似文献   

7.
The contradiction between the freshwater shortage and the large demand of freshwater by irrigation was the key point in cultivated lowland area of North China Plain. Water transfer project brings fresh water from water resource‐rich area to water shortage area, which can in turn change the hydrological cycle in this region. Major ions and stable isotopes were used to study the temporal variations of interaction between surface water and groundwater in a hydrological year after a water transfer event in November 2014. Irrigation canal received transferred Yellow River, with 2.9% loss by evaporation during water transfer process. The effect of transferred water on shallow groundwater decreased with increasing distance from the irrigation canal. Pit pond without water transfer receives groundwater discharge. During dry season after water transfer event, shallow groundwater near the irrigation canal was recharged by lateral seepage and deep percolation of irrigation, whereas shallow groundwater far from irrigation canal was recharged by deep percolation of deep groundwater irrigation. Canal water lost by evaporation was 2.7–17.4%. Influence of water transfer gradually disappeared until March as the water usage of agricultural irrigation increased. In the dry season, groundwater discharged to irrigation canal and pond; 2.2–31.6% canal water and 11.3–20.0% pond water were lost by evaporation. In the rainy season (June to September), surface water was fed mainly by precipitation and surface run‐off, whereas groundwater was recharged by infiltration of precipitation. The two‐end member mix model showed that the mixing ratio of precipitation in pond and irrigation canal were 73–83.4% (except one pond with 28.1%) and 77.3–99.9%, respectively. Transferred water and precipitation were the important recharge sources for shallow groundwater, which decreased groundwater salinity in cultivated lowland area of North China Plain. With the temporary and spatial limitation of water transfer effects, increased water transfer amounts and frequency may be an effective way of mitigating regional water shortage. In addition, reducing the evaporation of surface water is also an important way to increase the utilization of transfer water.  相似文献   

8.
Characterization of stable isotope compositions (δ2H and δ18O) of surface water and groundwater in a catchment is critical for refining moisture sources and establishing modern isotope–elevation relationships for paleoelevation reconstructions. There is no consensus on the moisture sources of precipitation in the Yellow River source region during summer season. This study presents δ2H and δ18O data from 111 water samples collected from tributaries, mainstream, lakes, and groundwater across the Yellow River source region during summertime. Measured δ18O values of the tributaries range from ?13.5‰ to ?5.8‰ with an average of ?11.0‰. Measured δ18O values of the groundwater samples range from ?12.7‰ to ?10.5‰ with an average of ?11.9‰. The δ18O data of tributary waters display a northward increase of 1.66‰ per degree latitude. The δ18O data and d‐excess values imply that moisture sources of the Yellow River source region during summertime are mainly from the mixing of the Indian Summer Monsoon and the Westerlies, local water recycling, and subcloud evaporation. Analysis of tributary δ18O data from the Yellow River source region and streamwater and precipitation δ18O data from its surrounding areas leads to a best‐fit second‐order polynomial relationship between δ18O and elevation over a 4,600 m elevation range. A δ18O elevation gradient of ?1.6‰/km is also established using these data, and the gradient is in consistence with the δ18O elevation gradient of north and eastern plateau. Such relationships can be used for paleoelevation reconstructions in the Yellow River source region.  相似文献   

9.
卞宇峥  薛滨  张风菊 《湖泊科学》2021,33(6):1844-1856
洪泽湖是淮河水系中最重要的湖泊之一,是我国的第四大淡水湖,它在防洪、灌溉、航运、跨流域调水以及水资源与水环境保护等方面发挥着重要作用.过去300年来,由于黄淮关系的演变和人类活动的影响,洪泽湖水域面积发生剧烈变化.研究湖泊水域空间变化有助于认识流域环境变化与人类活动影响.本文利用18世纪初以来的古地图、历史文献资料及1981-2016年期间的7期遥感影像数据,采用遥感和地理信息系统技术相结合的方法,分析了近300年来洪泽湖水域时空演变过程及其原因.研究结果表明:过去300年来,洪泽湖面积总体呈减少趋势,年际缩减速率为0.17%,且湖域范围总体表现为由四周向中心缩小的趋势,其中西南湖域的形态变化最为显著.具体而言,清中期以前,黄河多次夺泗入淮,洪泽湖面积变化受黄淮关系、高家堰等水利枢纽的修建以及降水等因素影响.至清末,洪泽湖面积由3078.78 km2下降至2335.73 km2,共减少743.05 km2,其空间形态也发生了剧烈变化,该时期黄河改道、降水以及人口增长导致的湖滨围垦是影响洪泽湖演变的主要原因.建国以来(1949-2016年),洪泽湖面积进一步缩小,由1757.60 km2下降至1488.43 km2,共减少了269.17 km2,其中1995-2000年间湖泊面积下降最为显著,共减少了281.43 km2,湖泊动态变化度达到2.78%,该时期自然因素对湖泊水域面积的影响减弱,而人口增长、围垦及水利工程的修建等人类活动逐渐成为影响洪泽湖演化的主导因素.  相似文献   

10.
The numerous lakes on the Tibetan Plateau play an important role in the regional hydrological cycle and water resources, but systematic observations of the lake water balance are scarce on the Tibetan Plateau. Here, we present a detailed study on the water cycle of Cona Lake, at the headwaters of the Nujiang‐Salween River, based on 3 years (2011–2013) of observations of δ18O and δ2H, including samples from precipitation, lake water, and outlet surface water. Short‐term atmospheric water vapor was also sampled for isotope analyses. The δ2H–δ18O relationship in lake water (δ2H = 6.67δ18O ? 20.37) differed from that of local precipitation (δ2H = 8.29δ18O + 12.50), and the deuterium excess (d‐excess) in the lake water (?7.5‰) was significantly lower than in local precipitation (10.7‰), indicating an evaporative isotope enrichment in lake water. The ratio of evaporation to inflow (E /I ) of the lake water was calculated using both d‐excess and δ18O. The E /I ratios of Cona lake ranged from 0.24 to 0.27 during the 3 years. Observations of atmospheric water vapor isotopic composition (δ A ) improved the accuracy in E /I ratio estimate over a simple precipitation equilibrium model, though a correction factor method provided nearly identical estimates of E /I ratio. The work demonstrates the feasibility of d‐excess in the study of the water cycle for lakes in other regions of the world and provides recommendations on sampling strategies for accurate calculations of E /I ratio.  相似文献   

11.
巴丹吉林沙漠气候干旱,蒸发强烈,与之形成鲜明对比的是沙漠腹地湖泊群的长久不衰,目前对于湖泊水分的补给来源仍存在争议.本文以水量均衡为基础,在苏木吉林湖区开展了降水、蒸发及湖水位和地下水位的动态监测,结合已有的水文地质资料建立地下水流动三维模型,重现湖区地下水位的季节动态变化,并基于模型进行水均衡分析.结果表明:苏木吉林湖区降水入渗补给量不足以平衡湖泊蒸发量,湖泊需要深层承压水的越流补给;湖水位和地下水位均呈现正弦曲线形态,11月最低,4月达到峰值,水位变幅分别为22和18 cm;湖区地下水多年平均总补给量为11620 m3/d,其中降水和承压水越流分别约占13%和87%,降水补给量夏季高、冬季低,承压水越流补给量季节变化不明显;承压水越流补给量可能主要来源于沙漠周边山区降水,未发现明显的水量亏空需要断裂导水来弥补.研究结果为巴丹吉林沙漠地下水资源分析及合理利用提供科学依据.  相似文献   

12.
This paper presents the use of stable isotopes of water for hydrological characterization and flow component partitioning in the Red River Delta (RRD), the downstream section of the Red River. Water samples were collected monthly during 2015 from the mainstream section of the river and its right bank tributaries flowing through the RRD. In general, δ18O and δ2H river signatures were depleted in summer–autumn (May–October) and elevated in winter–spring (November–April), displaying seasonal variation in response to regional monsoon air mass contest. The Pacific equatorial–maritime air mass dominates in summer and the northern Asia continental air mass controls in winter. Results show that water of the RRD tributaries stems solely from local sources and is completely separated from water arriving from upstream subbasins. This separation is due to the extensive management of the RRD (e.g., dykes and dams) for the purposes of irrigation and inundation prevention. Mainstream river section δ18O and δ2H compositions range from ?10.58 and ?73.74‰ to ?6.80 and ?43.40‰, respectively, and the corresponding ranges inside the RRD were from ?9.35 and ?64.27‰ to ?2.09 and ?15.80‰. A combination of data analysis and hydrological simulation confirms the role of upstream hydropower reservoirs in retaining and mixing upstream water. River water inside the RRD experienced strong evaporation characterized by depleted d‐excess values, becoming negative in summer. On the other hand, the main stream of the Red River has d‐excess values around 10‰, indicating moderate evaporation. Hydrograph separation shows that in upstream subbasins, the groundwater fraction dominates the river flow composition, especially during low flow regimes. Inside the RRD, the river receives groundwater during the dry season, whereas groundwater replenishment occurs in the rainy season. Annual evaporation obtained from this hydrograph separation computation was about 6.3% of catchment discharge, the same order as deduced from the difference between subbasin precipitation and discharge values. This study shows the necessity to re‐evaluate empirical approaches in large river hydrology assessment schemes, especially in the context of climate change.  相似文献   

13.
Tritium concentrations are used to trace water circulation in the Urumqi and Turfan basins in the Xinjiang, western China. Tritium analyses were made for 77 water samples of river waters, groundwaters, spring waters, lake waters and glacier ice collected in summers in 1992 and 1994. The tritium concentrations in the waters are in a wide range from 0 to 125 TU, most of which are considerably high compared with those of most waters in Japan, because tritium levels in precipitation in the area are over ten times as high as those in Japan. River waters originating in glacier regions contain melt glacier, the proportion of which is over 0.5 to river water. The mean resi-dence time of circulating meteoric water in the mountain regions is estimated to be about 15 years. Most groundwaters and spring waters in the flat regions are mainly derived from river waters originating in glacier regions. The groundwater of greatest tritium concentrations in wells in Urumqi City is derived from Urumqi River about 25 years ago. It takes several ten years for river water to pass the underground to many springs. Some groundwaters and spring waters have taken a long time more than 40 years to travel under the ground. Enrichment of tritium in lake water by evaporation is considered to estimate the contribution of groundwater flow to the recharge of lake. Various contributions of groundwater to lakes are inferred for the various type of salinity in closed or semi-closed lakes. The inflow rates of groundwater to salt lakes are small as against fresh water lakes.  相似文献   

14.
松原灌区建设对查干湖生态风险分析及对策   总被引:1,自引:1,他引:0  
松原灌区将对国家自然保护区查干湖周围的盐碱地实施大面积围垦,若大量高浓度碱性尾水直排入湖,将导致查干湖生态系统严重污染.对这一风险合理评估并防范,关系到湖区生态安全与灌区的可行.本文在对湖区生态环境及灌区尾水排放模式与含盐特性系统分析基础上,提出利用退化沼泽湿地(盐沼)构建湿地处理系统(生态缓冲区),而非直接入湖的构想.当灌区运行一定时期,尾水水质得到改善,再入湖发挥补水效应.同时在设计上采取盐碱地分批滚动开发,以控制年排盐总量,降低排盐强度;以及充分利用碱湖泡随机承泄,减轻对查干湖的压力,既可防止湖水污染,又可保证灌区建设可行.  相似文献   

15.
Based on stable isotopes in stream water, groundwater, and meltwater in the Kaidu River Basin, NW China, we estimated the evaporation enrichment of stable oxygen isotopes in different types of water and separated the contribution of each streamflow component in river run‐off. Our results indicated that δ18O and δ2H in stream water did not vary with altitude regularly but with seasons, with low concentrations in spring and high concentrations in summer. However, the seasonal variations of δ18O and δ2H in groundwater were not as obvious. The mean evaporation enrichment was between 26% and 44% for δ18O. Of the various water types under investigation, we found glaciers were influenced the most, showing an evaporation enrichment of 44%, followed by oasis groundwater (37%), stream water (36%), and mountain groundwater (26%). Overall, meltwater and groundwater were the predominant streamflow components, with their contributions were governed by temperature, and varied both temporally and specially. In the oasis region, groundwater was the predominant contributor (64% in spring, 50% in summer, and 66% in autumn), whereas in the mountains, groundwater was the dominant in spring (53%) and autumn (51%), and meltwater contributed the most in summer (52%). Precipitation contributed less than 15% to the streamflow.  相似文献   

16.
ABSTRACT

Evaporation is one of the most important components in the energy and water budgets of lakes and is a primary process of water loss from their surfaces. An artificial neural network (ANN) technique is used in this study to estimate daily evaporation from Lake Vegoritis in northern Greece and is compared with the classical empirical methods of Penman, Priestley-Taylor and the mass transfer method. Estimation of the evaporation over the lake is based on the energy budget method in combination with a mathematical model of water temperature distribution in the lake. Daily datasets of air temperature, relative humidity, wind velocity, sunshine hours and evaporation are used for training and testing of ANN models. Several input combinations and different ANN architectures are tested to detect the most suitable model for predicting lake evaporation. The best structure obtained for the ANN evaporation model is 4-4-1, with root mean square error (RMSE) from 0.69 to 1.35 mm d?1 and correlation coefficient from 0.79 to 0.92.
EDITOR M.C. Acreman

ASSOCIATE EDITOR not assigned  相似文献   

17.
选择1979-2016年间多时期、多类型、多光谱遥感数据,分析评价洞庭湖区内湖近40年的面积变化.结果表明,最近40年洞庭湖区内湖面积保持相对稳定,丰水期间呈上升趋势,枯水期间波动下降,2016年内湖总面积比1980s初减少3.94%.随着湖泊面积增加,湖泊水面面积变化的比例和幅度逐渐减小,大型湖泊(>10 km2)和中型湖泊(5~10 km2)面积相对稳定,小型内湖(<5 km2)面积变化尤为剧烈.内湖水面面积主要受降雨、蒸发等气候因素和生产生活取水、防洪排涝和退田还湖等人为活动调控.1980-2000年和2001-2015年两个时期,洞庭湖区多年平均降雨量呈现不同程度的下降趋势,多年平均蒸发量明显上升.三峡工程运行后,三口分流衰减,但水资源需求量不断增长,退田还湖和留蓄雨洪作为水资源使得丰水期间内湖水面面积增长,气候变化和水资源开发利用导致枯水期水面面积趋于减少.有必要加强洞庭湖区内湖的研究和保护,适当退田还湖提高湖泊率,优化三口水系格局,实施河湖水系连通工程,缓解洞庭湖区季节性水资源紧张问题.  相似文献   

18.
We simulated the effects of irrigation on groundwater flow dynamics in the North China Plain by coupling the NIES Integrated Catchment‐based Ecohydrology (NICE) model with DSSAT‐wheat and DSSAT‐maize, two agricultural models. This combined model (NICE‐AGR) was applied to the Hai River catchment and the lower reach of the Yellow River (530 km wide by 840 km long) at a resolution of 5 km. It reproduced excellently the soil moisture, evapotranspiration and crop production of summer maize and winter wheat, correctly estimating crop water use. So, the spatial distribution of crop water use was reasonably estimated at daily steps in the simulation area. In particular, NICE‐AGR reproduced groundwater levels better than the use of statistical water use data. This indicates that NICE‐AGR does not need detailed statistical data on water use, making it very powerful for evaluating and estimating the water dynamics of catchments with little statistical data on seasonal water use. Furthermore, the simulation reproduced the spatial distribution of groundwater level in 1987 and 1988 in the Hebei Plain, showing a major reduction of groundwater level due mainly to overpumping for irrigation. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

19.
Using lake Stechlin in northeastern Germany as an example of a small groundwater‐feed lake without surface inflows and outflows, we estimated the temporal scales and the variability ranges of the net groundwater contribution to the lake water budget. High‐resolution water level measurements by a bottom‐mounted pressure logger provided the background for the estimation of the total lake water budget. This method has demonstrated reliability for estimation of lake level variations during periods ranging from subdiurnal to perennial. The typical amplitudes of the synoptic‐to‐perennial variability characterizing the groundwater climate of lake Stechlin are estimated by comparing the two subsequent years 2006 and 2007; one of these years shows an extremely high, and the other an extremely low, annual precipitation–evaporation balance. The net groundwater flow, estimated as the difference between the total water budget and the precipitation–evaporation balance at the surface, revealed synoptic effects of lake water exfiltration into the groundwater aquifer following strong precipitation events. Perennial variations between wet and dry years superimposed seasonal oscillations. The probable origin of the latter is seasonality in the groundwater level on the watershed, although the exact amplitudes are subject to further quantification on account of seasonality in the evaporation estimation error. The results emphasize the non‐stationary behaviour of groundwater flow on timescales shorter than climatic ones. The analysis yielded a net quantitative relationship between groundwater flow and water balance at the lake surface: The water level changes in the lake due to evaporation and precipitation are damped to 60% because of the lake–groundwater exchange by means of intermittent infiltration and exfiltration events. Assuming the remaining 40% of the surface water budget may potentially result in perennial water level variability, we estimated an effect of the precipitation decrease on the lake water budget as predicted by the regional climate scenarios for the next century. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

20.
Stable isotopes analyses of oxygen and hydrogen of lake water were used to estimate the effect of evaporation (E) on the water quality of four shallow lakes in the Amapá State coast—Amazon/Brazil. These lakes, with different size and hydrologic conditions, were sampled during the course of the 2015/2016 El‐Niño (record‐breaking warming/drought in the Amazon rainforest). Hydrometeorological and water quality parameters were simultaneously performed to the isotopic sampling. The results showed that the evaporation process and the water quality can be explained by climate season and distances from the Atlantic Ocean. Lake evaporation losses ranged from ≈0–22% during the wet season in April/2016 and ≈35.7% during the dry season in November/2015. As expected, the evaporation of lake water was greater during the dry season, but it was higher for lakes farther away from the Atlantic Ocean compared with more coastal lakes due to tidal preponderance and the influence of major river channels. The more inland estuarine lakes showed a lower level of salinity (0.00–0.03 ppt) compared with those closer to the Atlantic Ocean (0.01–0.08 ppt). The El Niño phenomenon, with a lower precipitation in the Amazon basin, may initiate salinization of lakes closer to the Atlantic Ocean. Furthermore, strong mean seasonal variations of evaporation (0.06 ≤ E ≤ 0.22) and other hydrologic parameters were observed (precipitation, water temperature, and water depth), with significant effects on the water quality such as salinity, dissolved oxygen, chlorophyll (p < .05). We conclude that the occurrence of the extreme climatic events can disrupt the biogeochemical and hydrological balance of these aquatic ecosystems and salinization of lakes closer to the Atlantic Ocean.  相似文献   

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