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1.
It is possible that climate changes and sea level fluctuations (allogenic processes) are and will cause major changes in mangrove dynamics. However, other driving forces may be significantly affecting this system. Distinguishing allogenic and autogenic influence on mangroves is a challenging question, because mechanisms related to the natural dynamics of depositional environments (autogenic processes) have strong influences on the establishment and degradation of mangroves. Thus, impacts on mangroves caused by autogenic processes may be erroneously attributed to allogenic mechanisms. Therefore, it is imperative to identify the ‘fingerprint’ of global changes in modern mangrove dynamics. In order to characterize the influence of these forces on mangroves, this work has used geomorphology and vegetation maps integrated with sedimentological and palynological data, radiocarbon dating, as well as δ13C, δ15N and C/N from sedimentary organic matter. The inter‐proxy analyses reveal an estuarine influence with mangrove development along the Ceará Mirim River, north‐eastern Brazil, since ~6920 cal yr bp , after the post‐glacial sea level rise. Relative sea level (RSL) has been stable during the middle and late Holocene. Mangrove establishment along this fluvial valley begins at about 6920 cal yr bp , caused by the sea‐level stabilization, an allogenic influence. However, after its establishment, wetland dynamics were mainly controlled by autogenic factors, related to channel migrations, instead of allogenic process. Some influence of sea‐level and climate changes on mangrove dynamics in this estuarine channel have been weakened by more intense tidal channels activities. Therefore, the expansion and contraction of mangrove areas along the estuary of the Ceará Mirim River since 6920 cal yr bp has been mainly influenced by channel dynamics that regulate the accretion and erosion of mangrove substrates. Copyright © 2018 John Wiley & Sons, Ltd.  相似文献   

2.
Generally, palaeoenvironmental interpretations consider only allogenic processes, when autogenic factors may have a strong influence on proxies of stratigraphic sequences. For instance, the Holocene history of the vegetation along the southern littoral of the State of Bahia in north‐eastern Brazil is characterized by mangrove dynamics controlled by allogenic processes. However, over smaller timescales (~700 years), autogenic processes may have controlled vegetation dynamics and hence observed pollen distribution. This work proposes tidal channel dynamics as one of the main cause for changes in pollen assemblage along the studied stratigraphic profiles during the last centuries, based on sedimentology, pollen and elemental analysis (δ13C, δ15N and C/N) and radiocarbon dating of sedimentary organic matter from two cores sampled from an abandoned meander and a tidal flat at the mouth of the Jucuruçu River. One core was sampled from a mangrove formed during the past ~550 cal yr bp . Another core recorded sediments in a várzea forest (swamp seasonally and permanently inundated by freshwater) located ~2.7 km from the current shoreline, which displayed a maximum age of ~680 cal yr bp . Two facies associations were identified: tidal channel (A) and tidal flat/oxbow lake (B). This work proposes allogenic processes as the main driving forces controlling the wetlands dynamics at the studied site during the Holocene. However, our data also reveal that part of the changes in vegetation over the last ~700 years reflect tidal channels and tidal flats development, which represent autogenic processes. The change in timescale analysis from the Holocene to recent centuries may have weakened the influence of allogenic factors. However, this needs interpretation with reference to the spatial scale of the depositional environment as the larger the depositional system analyzed, the stronger the influence of autogenic processes on stratigraphic sequences over longer timescales. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

3.
The Holocene evolution of the Canning Coast of Western Australia has largely been overlooked so far mainly due to its remoteness and low population density. We report on new data from a sequence of foredunes inside the macro‐tidal Admiral Bay, 110 km southwest of Broome. Based on sediment cores, differential global positioning system (dGPS)‐based elevation transects, and stratigraphical analyses on outcrops of the relict foredunes, we aim at reconstructing Holocene coastal changes and relative sea levels (RSLs), as well as identifying and dating imprints of extreme‐wave events. Sedimentary analyses comprise the documentation of bedding structures, foraminiferal content and macrofaunal remains, grain size distribution, and organic matter. The chronological framework is based on 26 carbon‐14 accelerator mass spectrometry (14C‐AMS) datings. Marine flooding of the pre‐Holocene surface landward of the 2.5 km‐wide foredune barriers occurred 7400–7200 cal bp , when mangroves colonized the area. After only 200–400 years, a high‐energy inter‐tidal environment established and prevailed until c. 4000 cal bp , before turning into the present supralittoral mudflat. During that time, coastal regression led to beach progradation and the formation of aligned foredunes. Drivers of progradation were a stable RSL or gradual RSL fall after the mid‐Holocene and a positive sand budget. The foredunes overlie upper beach deposits located up to >2 m above the present upper beach level and provide evidence for a higher mid‐Holocene RSL. Discontinuous layers of coarse shells and sand are intercalated in the foredunes, indicating massive coastal flooding events. One such layer was traced over three dune ridges and dated to c. 1700–1550 cal bp . However, it seems that most tropical cyclones induce net erosion rather than deposition at aligned foredunes and thus, they are only suitable for reconstructing temporal variability if erosional features or sedimentation reliably tied to these events can be identified and dated accurately. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

4.
Seasonal changes in water quality were measured in samples taken at various distances from shallow water across mudflat to mangroves during flood period and from mangroves across mudflat to shallow water during ebb period in a subtropical mangrove estuary (Zhangjiang Estuary, Fujian, China). The TN (total dissolved nitrogen), TP (total dissolved phosphorus), COD (chemical oxygen demand), and DOC (dissolved organic carbon) contents during the flood period were significantly higher than those during the ebb period. In contrast, the opposite was true for the POC (particulate organic carbon) content and transparency. The mangroves at Zhangjiang Estuary may trap nutrients at rates of 90.5 g N/m2/yr, 2.2 g TP/m2/yr, and 13.7 g C/m2/yr in the form of DOC, and export POC at a rate of 81.8 g/m2/yr. Our results support the hypothesis that the maintenance of estuarine water quality by mangroves occurs during flood periods.  相似文献   

5.
Tidal circulation and energy dissipation in a shallow, sinuous estuary   总被引：2，自引：0，他引：2  
The tidal dynamics in a pristine, mesotidal (>2 m range), marsh-dominated estuary are examined using moored and moving vessel field observations. Analysis focuses on the structure of the M 2 tide that accounts for approximately 80% of the observed tidal energy, and indicates a transition in character from a near standing wave on the continental shelf to a more progressive wave within the estuary. A slight maximum in water level (WL) occurs in the estuary 10–20 km from the mouth. M 2 WL amplitude decreases at 0.015 m/km landward of this point, implying head of tide approximately 75 km from the mouth. In contrast, tidal currents in the main channel 25 km inland are twice those at the estuary mouth. Analysis suggests the tidal character is consistent with a strongly convergent estuarine geometry controlling the tidal response in the estuary. First harmonic (M 4) current amplitude follows the M 2 WL distribution, peaking at mid-estuary, whereas M 4 WL is greatest farther inland. The major axis current amplitude is strongly influenced by local bathymetry and topography. On most bends a momentum core shifts from the inside to outside of the bend moving seaward, similar to that seen in unidirectional river flow but with point bars shifted seaward of the bends. Dissipation rate estimates, based on changes in energy flux, are 0.18–1.65 W m−2 or 40–175 μW kg–1. A strong (0.1 m/s), depth-averaged residual flow is produced at the bends, which resembles flow around headlands, forming counter-rotating eddies that meet at the apex of the bends. A large sub-basin in the estuary exhibits remarkably different tidal characteristics and may be resonant at a harmonic of the M 2 tide.  相似文献   

6.
The Amazon Macrotidal Mangrove Coast (AMMC) is a large (~7500 km2) contiguous mangrove fringe eastwards from the Amazon River mouth. It encompasses dozens of interconnected bays intercalated with mangrove peninsulas. Mud accumulates on the mangrove flats, whereas the bed of the bays and channels is generally sandy. In this study we investigated the circulation, sediment transport and deposition in a central site at one of these mangrove peninsulas. The study was undertaken during the dry period, when there is no influence of the Amazon River plume and minimum local freshwater inflow. Current and suspended-sediment concentration were monitored in a feeder channel on the mangrove flat along a ~1000 m section oriented along the peninsula axis. Sediment deposition was also measured on the flat. Our results show there was a strong exchange between the neighboring bays. Channel currents were flood dominant, reaching up to >1 m s−1, with residual water and sediment transport westwards. Suspended sediment concentration (SSC) in the channel was directly related to velocity magnitude, ranging between 50 and 350 mg L−1. The flat was flooded in a way that indicated the tidal wave evolves westwards, nearly parallel to the AMMC shoreline. Currents on the flats were much slower than those in the channel and showed slight ebb dominance. However, SSC was higher during the flood than ebb, clearly indicating settling during the current deceleration and limited erosion during the following ebb–flow acceleration. The net sediment transport across the section was 60 tons westwards for the period of the experiment (~4 days). The mean deposition rate was 0.006 kg m−2 s−1 (or 1.4 kg m−2 per tide), which was higher than rates from other reported assessments in mangroves. The set of results indicate very large internal sediment reworking in the AMMC. © 2019 John Wiley & Sons, Ltd.  相似文献   

7.
The morphodynamics of shallow, vertically well-mixed estuaries, characterised by tidal flats and deeper channels, have been investigated. This paper examines what contributes to flood/ebb-dominant sediment transport in localised regions through a 2D model study (using the TELEMAC modelling system). The Dyfi Estuary in Wales, UK has been used as a case study and, together with idealised estuary shapes, shows that shallow water depths lead to flood dominance in the inner estuary whilst tidal flats and deep channels cause ebb dominance in the outer estuary. For medium sands and with an artificially ‘flattened’ bathymetry (i.e. no tidal flats), the net sediment transport switches from ebb-dominant to flood-dominant where the parameter a/h (local tidal amplitude ÷ local tidally averaged water depth) exceeds 1.2. Sea level rise will reduce this critical value of a/h and also reduce the ebb-directed sediment transport significantly, leading to a flood-dominated estuarine system. A similar pattern, albeit with greater transport, was simulated with tidal flats included and also with a reduced grain size. This suggests that analogous classifications for flood/ebb asymmetry of the tide in estuaries as a whole may not represent the local sediment transport in sufficient detail. Through the Dyfi simulations, the above criterion involving a/h is shown to be complicated further by augmented flow past a spit at the estuary mouth which gives rise to a self-maintaining scour hole. Simulations of one year of bed evolution in an idealised flat-bottomed estuary, including tidal flow past a spit, recreate the flood/ebb dominance on either side of the spit and the formation of a scour hole in between. The erosion rate at the centre of the hole is reduced as the hole deepens, suggesting the establishment of a self-maintaining equilibrium state.  相似文献   

8.
The northern Brazilian coast, east of the Amazon River is characterized by several macrotidal estuarine systems that harbor large mangrove areas with approximately 7600 km2. The Marapanim Estuary is influenced by macrotidal regime with moderate waves influence. Morphologic units were investigated by using remote sensing images (i.e., Landsat-7 ETM+, RADARSAT- 1 Wide and SRTM) integrated with bathymetric data. The modern sedimentary deposits were analyzed from 67 cores collected by Vibracore and Rammkersonde systems. Analysis of morphology and surface sedimentary deposits of the Marapanim River reveal they are strongly influenced by the interaction of tidal, wave and fluvial currents. Based on these processes it was possible to recognize three distinct longitudinal facies zonation that revels the geological filling of a macrotidal estuary. The estuary mouth contain fine to medium marine sands strongly influenced by waves and tides, responsible for macrotidal sandy beaches and estuarine channel development, which are characterized by wave-ripple bedding and longitudinal cross-bedding sands. The estuary funnel is mainly influenced by tides that form wide tidal mudflats, colonized by mangroves, along the estuarine margin, with parallel laminations, lenticular bedding, root fragments and organic matter lenses. The upstream estuary contains coarse sand to gravel of fluvial origin. Massive mud with organic matter lenses, marks and roots fragments occur in the floodplain accumulates during seasonal flooding providing a slowly aggrading in the alluvial plain. This morphologic and depositional pattern show easily a tripartite zonation of a macrotidal estuary, that are in the final stage of filling.  相似文献   

9.
The outflow of brackish waters from the Tees estuary on an ebb tide forms a plume which is initially spread by the action of gravity. Under quiescent conditions, the rate of vertical mixing of the brackish field is relatively slow and an area of low salinity may form in the surface waters as a result of the superimposition of the outflow plumes from successive tides. A field area of some 70 km2 has been observed to be enclosed by the 34.2 × 10?3 contour.Averaged over a tidal period, the estuary outflow from the Tees forms a broad plume of low-salinity water which extends to seaward of the 20-m contour. The movement of the field thereafter depends on the residual coastal drift which runs either to the northwest or to the southeast with a typical speed of 0.015 m s?1. The tidally averaged vertical mixing coefficient in this offshore field was estimated to be about 10?4 m?2 s?1, which is similar to that off the Wear estuary and an order of magnitude smaller than that calculated for the waters off the Humber.  相似文献   

10.
This study focuses on the medium scale morphodynamics of the tidal flat and channel system Fedderwarder Priel, located in the Outer Weser estuary (Wadden Sea, Germany). Tidal channels and adjacent flats are highly dynamic systems whose morphologic evolution are driven by tidal, wind, and wave forcings. These coastal environments are an important ecosystem and react to changes in hydrodynamic conditions in various spatial and temporal scales. Based on annual medium-resolution digital elevation models from 1998 to 2016, we describe changes in the surface area over depth with hypsometries and use vertical dynamic trends in order to analyze and visualize the morphologic evolution of the Fedderwarder Priel and adjacent tidal channels. It is shown that several intertidal flats rise in the order of 1.3 to 5.6 cm/year. The findings indicate that the Outer Weser estuary was not in an equilibrium state for the investigated period, and tidal flats accreted with a rate exceeding mean sea level rise.  相似文献   

11.
The range of relative sea level rise in the northwestern South China Sea since the Last Glacial Maximum was over 100 m. As a result, lowland regions including the Northeast Vietnam coast, Beibu Gulf, and South China coast experienced an evolution from land to sea. Based on the principle of reconstructing paleogeography and using recent digital elevation model, relative sea level curves, and sediment accumulation data, this paper presents a series of paleogeographic scenarios back to 20 cal. ka BP for the northwestern South China Sea. The scenarios demonstrate the entire process of coastline changes for the area of interest. During the late glacial period from 20 to 15 cal. ka BP, coastline slowly retreated, causing a land loss of only 1×104 km2, and thus the land-sea distribution remained nearly unchanged. Later in 15–10 cal. ka BP coastline rapidly retreated and area of land loss was up to 24×104km2, causing lowlands around Northeast Vietnam and South China soon to be underwater. Coastline retreat continued quite rapidly during the early Holocene. From 10 to 6 cal. ka BP land area had decreased by 9×104km2, and during that process the Qiongzhou Strait completely opened up. Since the mid Holocene, main controls on coastline change are from vertical crustal movements and sedimentation. Transgression was surpassed by regression, resulting in a land accretion of about 10×104km2. Supported by Key Laboratory of Marginal Sea Geology, Chinese Academy of Sciences (Grant No. MSGL0711), the Guangdong Natural Science Foundation (Grant No. 04001309) and Open Fund of the Key Laboratory of Marine Geology and Environment, Chinese Academy of Sciences (Grant No. MGE2007KG04)  相似文献   

12.
The majority of the world's mangrove forests occur on mostly mineral sediments of fluvial origin. Two perspectives exist on the biogeomorphic development of these forests, i.e. that mangroves are opportunistic, with forest development primarily driven by physical processes, or alternatively that biophysical feedbacks strongly influence sedimentation and resulting geomorphology. On the Firth of Thames coast, New Zealand, we evaluate these two possible scenarios for sediment accumulation and forest development using high‐resolution sedimentary records and a detailed chronology of mangrove‐forest (Avicennia marina) development since the 1950s. Cores were collected along a shore‐normal transect of known elevation relative to mean sea level (MSL). Activities for lead‐210 (210Pb), caesium‐137 (137Cs) and beryllium‐7 (7Be), and sediment properties were analysed, with 210Pb sediment accumulation rates (SARs), compensated for deep subsidence (~8 mm yr?1) used as a proxy for elevation gain. At least four phases of forest development since the 1950s are recognized. An old‐growth forest developed by the late‐1970s with more recent seaward forest expansion thereafter. Excess 210Pb profiles from the old‐growth forest exhibit relatively low SARs near the top (7–12 mm yr?1) and bottom (10–22 mm yr?1) of cores, separated by an interval of higher SARs (33–100 mm yr?1). A general trend of increasing SAR over time characterizes the recent forest. Biogeomorphic evolution of the system is more complex than simple mudflat accretion/progradation and mangrove‐forest expansion. Surface‐elevation gain in the old‐growth forest displays an asymptotic trajectory, with a secondary depocentre developing on the seaward mudflat from the mid‐1970s. Two‐ to ten‐fold increases in 210Pb SARs are unambiguously large and occurred years to decades before seedling recruitment, demonstrating that mangroves do not measurably enhance sedimentation over annual to decadal timescales. This suggests that mangrove‐forest development is largely dependent on physical processes, with forests occupying mudflats once they reach a suitable elevation in the intertidal. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

13.
Mangrove forests dominate many tropical coastlines and are one of the most bio‐diverse and productive environments on Earth. However, little is known of the large‐scale dynamics of mangrove canopies and how they colonize intertidal areas. Here we focus on a fringe mangrove forest located in the Mekong River Delta, Vietnam; a fast prograding shoreline where mangroves are encroaching tidal flats. The spatial and temporal evolution of the mangrove canopy is studied using a time series of Landsat images spanning two decades as well as Shuttle Radar Topography Mission (SRTM) elevation data. Our results show that fast mangrove expansion is followed by an increase in Normalized Difference Vegetation Index (NDVI) in the newly established canopy. We observe three different dynamics of the mangrove fringe: in the southwest part of the fringe, near a deltaic distributary where the fringe boundary is linear, the canopy expands uniformly on the tidal flats with a high colonization rate and high NDVI values. In the northeast part of the fringe, near another distributary, the canopy expands at a much lower rate with low NDVI values. In the fringe center, far from the river mouths, the fringe boundary is highly irregular and mangroves expansion in characterized by sparse vegetated patches displaying low NDVI values. We ascribe these different dynamics to wave action and southwest longshore transport triggered by energetic northeasterly monsoons during winter. We further link the large‐scale dynamics of the fringe to small‐scale physical disturbances (waves, erosion and deposition) that might prevent the establishment of mangrove seedlings. Based on these results, we include mangrove encroachment in an already published conceptual model of progradation of the Mekong River Delta. We conclude that high NDVI values and a constantly linear vegetation–water interface are indicative of stable mangrove canopies undergoing fast expansion, probably triggered by sediment availability at the shore. Our results can be applied more generally to mangrove forests growing in minerogenic and high tidal range environments with high sediment inputs. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

14.
The goal of this work was to understand the main hydrodynamic processes acting on tidal flats of the coast of Amapá near the mouth of the Amazon River, and how they change over the short term (~ 20 years). The analysis of morphological and geobotanical units was carried out by applying processing and interpretation methods to optical and synthetic aperture radar (SAR) images, combined with data on water salinity, maximum flood height, sedimentary facies data, rainfall and river discharge. The temporal analysis of morphological and geobotanical units suggests the relative stabilization of savannah, ‘várzea’ and mangrove areas during the drier period and increasing tidal amplitude between 1987 to 1997. The wetter period and decreasing tidal amplitude between 1997 to 2008 led to an increase in the area of ‘várzea’ and lakes over savannah, and the expansion of mangroves mainly over the inundated field and tidal mud/mixed flats. Therefore, the decrease in rainfall index during the drier period is well‐correlated with the reduction of the Calçoene River discharge and jointly with increasing tidal amplitude favored the increase of migration rate of the mud bank and erosion profile along the littoral. It was followed by the increase of the Calçoene River discharge and jointly with decreasing tidal amplitude during the wetter period, favoring the development of mangroves on muddy substrates near the coastline. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
The freshwater budget of a tidal flat area is evaluated from long-term hydrographic time series from an observation pole positioned in a tidal channel in the Hörnum Basin (Germany). For each tidal cycle, the freshwater budget is calculated from the total imported and exported water volumes and the corresponding mean densities. The variability of the budget on a tidal scale is characterised by a period of twice the tidal period, exhibiting a minimum when the tidal flats are dry around daylight hours during the foregoing low tide, and a maximum when low tide occurs at night; enhanced evaporation on the flats at daylight hours is identified as the driving process. On the average over one year, while winter observations are missing, the freshwater budget is negative for the years 2002–2005 and positive only for 2006. The interannual mean is negative and amounts to a freshwater loss of about 2 mm day−1, although the large-scale climate in this region is humid. The results demonstrate that the bulk parametrisations for the latent and sensible heat flux between the ocean and the atmosphere must not be applied for the tidelands.  相似文献   

16.
《水文科学杂志》2013,58(1):166-170
Abstract

Freshwater and sediment are crucial to the development and health of aquatic and wetland ecosystems in deltaic coastal regions. This study examines the long-term freshwater inflow (1940–2002) and total suspended solid loading (1978–2001), and their relationships with climate variables in three major river watersheds to Lake Pontchartrain, the largest inland estuary in the USA. The results show an average total annual freshwater inflow of 5.04 km3 and an average total annual sediment loading of 210 360 t, with the highest contributions from the Amite River watershed. Over 69% of annual inflow occurred within the six months from December to May. About 66–71% of the annual total suspended solid loading occurred within the four months from January to April. An increasing trend of annual water inflow and sediment discharge was found in the Amite River watershed over the past 60 years, coinciding with the fastest population growth in this upper Lake Pontchartrain basin.  相似文献   

17.
This work presents the first synthesis of secular to millenary morphological evolutions and stratigraphy of a wave-dominated estuary, the Arcachon lagoon, from a combination of unpublished bathymetric maps (1865 and 2001), core results and high-resolution seismic profiles recorded for the first time in this lagoon. The Arcachon lagoon is located on the Atlantic coast of France, facing the wave-dominated shelf of the Bay of Biscay. It is a mesotidal semi-enclosed environment of about 160 km2.The sediment budget of the Arcachon lagoon was computed by subtracting the 1865 bathymetric map from that of 2001. The computed volume difference is low (?9.9±35×106 m3 in 136 yrs) and is the result of the balance between erosion and accretion that occurs within tidal channels and tidal flats, respectively. This morphological evolution pattern is explained by low sediment supply and also by the tidal distortion resulting from the morphology of the lagoon. Deep channels connected to the inlet are dominated by ebb currents inducing erosion. Tidal flats and transverse channels display weak or flood-dominated tidal currents leading to the deposition of silts. The areas of tidal flat siltation locally correlate with the presence of oyster farms, suggesting the influence of Man on the lagoon sediment-fill. Transverse channel-infill is related to weak tidal currents resulting from the hydraulically inefficient orientation of these channels which served as an ancient drainage network.Evidence for tidal channel-infill and channel abandonment are also provided by seismic profiling and cores. The upper stratigraphic succession of the lagoon (about 10 m thick) includes four main stratigraphic units dominated by channel-fills. The two lower units (around 7500–2800 yrs BP) display tabular-shape sandy channels interpreted to be records of the open estuarine phase of the Arcachon lagoon. The two upper units (around 2800 yrs BP to present-day) display U-shaped mixed sand-and-mud channel-fills interpreted to be records of the closure of the lagoon. Given that the basal estuarine units are transgressive and the upper lagoonal units are regressive, the main stratigraphic change at around 2800 yrs BP is interpreted as being the maximum flooding surface (MFS). This late MFS is explained by the low sediment supply. It is proposed that the transition from the estuarine to the lagoonal phase is related to the development of the Cap-Ferret spit in response to an increase in the ratio between wave power to tide power. This change in wave-to-tide ratio may be triggered by wave power increase following the Subboreal/Subatlantic climate instability or a decrease in tide power following a decrease in tidal prism related to the lagoon sediment-fill.Thus, the evolution of the Arcachon lagoon over the last millenaries was mainly controlled by its spit development, leading to a wave-dominated estuary in terms of its geomorphology. Once it was partially closed, extensive mud flats developed in the lagoon which became ebb-dominated.  相似文献   

18.
In this paper the reaction of the salt‐/freshwater interface due to the changes in the Dead Sea level are elaborated at in details by using the inflows into the Dead Sea, the outflows due to evaporation losses and artificial discharges, and the hydrographic registrations of the Dead Sea level. The analyses show that the interface seaward migration resulted in a groundwater discharge of around 423 Mio m3 per meter drop in the level of the Dead Sea in the period 1994–1998 and of around 525 Mio m3/m in the period 1930–1937. The additional amount of groundwater joining the Dead Sea due to the interface seaward migration was 51 Mio m3 per one square kilometer of shrinkage in the area of the Dead Sea in the period 1930–1937 and 91 Mio m3/km2 in the period 1994–1998. The riparian states of the Dead Sea are nowadays loosing 370 Mio m3/a of freshwater to the Dead Sea through the interface readjustment mechanisms as a result of their over exploitation of waters which formerly fed the Dead Sea.  相似文献   

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