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In Cisjordan, surface- and groundwater flow are either towards the Jordan Valley-Dead Sea-Arava Valley (the Rift) or the Mediterranean Sea. Due to upstream exploitation by riparians to the Jordan River, the historical annual flow, which fluctuated between 250 and 1100 Mm3, has declined to a mere 100-200 Mm3. The remaining flow south of Lake Kinneret is highly polluted and heavily loaded with salts. Lake Kinneret (Sea of Galilee) is one of the major water resources in the area. Annually, between 200 and 700 Mm3 reach the Lake as surface and groundwater flow. The relatively high salinity of the Lake is caused by thermomineral water discharging from springs and seepages located onshore and on the bottom of the Lake. The main factors causing deterioration of the groundwater quality in the Rift are of geogenic character. These are different types of brines, whose outflow and penetration into freshwater aquifers was triggered by overpumpage. Contemporary encroachment of seawater caused by intensive water exploitation in the Coastal Plain is manageable and reversible. However, due to lack of hydrogeological evidence, no such statement can be made about the circulation of seawater beneath the Coastal Plain and into the deep-seated Yarkon-Taninim aquifer or the upflow of brines in the Rift.The flow regimes of the different brine bodies could not be elucidated. Whether each such brine-body flows by its particular hydrological regime or whether the movement of the different bodies is intradependent or interdependent with the regional movement of fresh groundwater, remain open questions. Therefore, sustainable development of groundwater resources is clearly dependent on the elucidation of the relationship between changes in the pressure of the brine with depth and its relationship to the overlying freshwater.The average total annual recharge of all water sources in Cisjordan is 1820 Mm3, which means that the total production of water must be managed within the limits of this annual volume. During drought years, total groundwater extraction exceeds the safe yield, causing drastic lowering of water levels and upflow of saline waters from greater depths.Because of the structural complexity of aquifers and hydrochemical variability of the numerous groundwater bodies, new hydrochemical methods have been developed for the identification of groundwater bodies and for the elucidation of their origins. These methods combine macrochemical, microchemical, and isotopic evidences. By combining distribution patterns of rare earths, yttrium and stable isotopes, a complete picture of catchment lithology and the altitude and latitude of precipitation could be obtained.The area west of the Jordan River is characterized by the occurrence of transboundary surface- and groundwater basins in which fresh and saline water and brines flow across political borders between Israel and the Palestinian Authority. It is very difficult to assess separately the annual safe yield of water resources for each of the two national entities. Neither country may dispose independently of its waters and is usually at the mercy of the other riparian. There is as yet no general multilateral international treaty in force allocating the water resources of international watercourses. At present there are two rules for the management of the waters of an international drainage basin—the rule of Equitable Distribution, and the obligation Not to Cause Significant Harm. The rules of equitable distribution have tended to focus on the issue of quantities of water rather than on quality of water, which is really relevant to the issue of equitable distribution. Future negotiations on the uses of the basin will need to deal with issues of characteristic salinities and geochemical features and on their impact on equitable sharing of water resources. 相似文献
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Wolfram Kloppmann Haim Chikurel Géraldine Picot Joseph Guttman Marie Pettenati Avi Aharoni Catherine Guerrot Romain Millot Irina Gaus Thomas Wintgens 《Applied Geochemistry》2009
Boron and Li isotopes have been tested as environmental tracers of treated sewage injected into a sandy aquifer (Shafdan reclamation project, Israel). During a 38 days injection test in a newly dug injection well, a conservative artificial tracer (Br−) was monitored together with δ11B and δ7Li in the injectate, in the unsaturated soil zone (porous cup) and an observation well in the aquifer. In spite of B and Li concentrations in the injectate close to background values, significant shifts of the isotope signatures could be observed over the duration of the injection test. Boron isotope ratios show a breakthrough curve delayed with respect to Br− breakthrough due to some reversible sorption on the aquifer material. No isotope fractionation was observed in the unsaturated or the saturated zone so that B isotopes can be considered as conservative in the investigated part of the aquifer system. Lithium isotopes are strongly fractionated, probably due to sorption processes. Lithium concentrations point to a Li sink in the system, δ7Li values vary strongly with a tendency of 7Li depletion in the liquid phase over the duration of the experiment. This is opposite to the expected preferential sorption of 6Li onto clay minerals. Boron isotopes reveals a valuable tracer of artificial recharge of freshwaters derived from treated sewage, both for short term tracer tests and for long-term monitoring of artificial recharge, even if in aquifers with higher clay contents, sorption-linked isotope fractionation cannot be excluded. More data are needed on Li isotope fractionation in natural groundwater systems to assess the potential of this tracer as monitoring tool. 相似文献
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Hydrogeology Journal - The water-level drawdown in pumping wells is the sum of two components: aquifer loss and well loss. The latter results from mostly turbulent and nonlaminar flow in and around... 相似文献
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An increase in salinity and change from oxic to anoxic conditions are observed in the Upper subaquifer of the Judea Group
in the Kefar Uriyya pumping field at the western foothills of the Judea Mountains, Israel. Hydrogeological data indicate that
the change, which occurs over a distance of only a few kilometers, coincides with a transition from confined to phreatic conditions
in the aquifer. The deterioration in the water quality is explained as a result of seepage of more saline, organic-rich water
from above, into the phreatic "roofed" part of the aquifer. The latter is derived from the bituminous chalky rocks of the
Mount Scopus Group, which confine the aquifer in its southeastern part. In this confined part, water in perched horizons within
the Mount Scopus Group cannot leak down and flow westward while leaching organic matter and accumulating salts. However, upon
reaching the transition area from confined to phreatic conditions, seepage to the Judea Upper subaquifer is possible, thereby
allowing it to be defined as a leaky aquifer. The incoming organic matter consumes the dissolved oxygen and allows bacterial
sulfate reduction. The latter accounts for the H2S in the aquifer, as indicated by sulfur isotopic analyses of coexisting sulfate and sulfide. Thus, from an aquifer management
point of view, in order to maintain the high quality of the water in the confined southeastern part of the Kefar Uriyya field,
care should be taken not to draw the confined-roofed transition area further east by over pumping.
Electronic Publication 相似文献
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The recent publication of an expansive national dataset, the Integrated Public Use Microdata Sample, allows for new analyses of the historical geography and settlement of various immigrant and ethnic groups in the United States. The present research explores the growth, development, and geographic dispersion of the ethnic Mexican population, and outlines some of the demographic and social characteristics within significant clusters of this population in the United States across the first half of the twentieth century. The analysis does not attempt to overturn other geographies and ethnographies in Mexican American history, but through its ability to elucidate broad, national patterns it is able to create a more dynamic view of settlement, demonstrating the role of immigrants and of women immigrants in particular. Results indicate that place matters: the geographical context of arrival and settlement were key factors in differentiating communities and the lives of those who lived in them. 相似文献
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Nathaniel B. Guttman 《Climatic change》1991,18(1):95-105
Compilations of data are available from many sources. Users of these data should be aware of the assumptions, limitations, etc. inherent in the development of the data sets. Knowledge of these factors will allow for better interpretation of the results of studies that are based on these data. This paper presents guidelines for scrutinizing data compiled by someone other than the researcher. Applications of the principles are given by an example of problems in a basic data set and of an analysis of some statistical considerations of the adjustment procedure used in the development of a new climatic data set that was compiled for the purpose of detecting and monitoring climatic chnge. A realistic approach to applying the principles is suggested. This approach is based on shared responsibilities between the compiler and user of a data set. 相似文献
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Concurrent Salinization and Development of Anoxic Conditions in a Confined Aquifer,Southern Israel 
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下载免费PDF全文 An ancient, brackish, anoxic, and relatively hot water body exists within the Yarqon‐Tanninim Aquifer in southern Israel. A hydrogeological‐geochemical conceptual model is presented, whereby the low water quality is the outcome of three conditions that are met simultaneously: (1) Presence of an organic‐rich unit with low permeability that overlies and confines the aquifer; the confining unit contains perched horizons with relatively saline water. (2) Local phreatic/roofed conditions within the aquifer that enable seepage of the organic‐rich brackish water from above. The oxidation of the dissolved organic matter in the seeping water consumes the dissolved oxygen and continues through bacterial sulfate reduction, with H2S as a product. These exothermic reactions result in some heating. (3) The seeping water comprises a relatively large portion of the water volume. In the presented case study, the latter condition first developed in the Late Pleistocene following climate change, which led to a dramatic decline in recharge. Consequently, water flow in the local basin has nearly ceased, as evident by old water ages, specific isotopic composition, and nearly equipotential water levels. The continuous seepage from above into the almost stagnant water body has resulted in degraded water quality. Seepages of organic‐rich brackish water exist at other sites throughout the aquifer but have limited impact on the salinity and redox conditions due to the dynamic water flow, which flushes the seeping water, that is, the third condition is not met. The coexistence of the above three conditions may explain the development of anoxic and saline groundwater in other aquifers worldwide. 相似文献
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