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Concerns about the water–energy–food (WEF) nexus have motivated many discussions regarding new approaches for managing water, energy and food resources. Despite the progress in recent years, there remain many challenges in scientific research on the WEF nexus, while implementation as a management tool is just beginning. The scientific challenges are primarily related to data, information and knowledge gaps in our understanding of the WEF inter-linkages. Our ability to untangle the WEF nexus is also limited by the lack of systematic tools that could address all the trade-offs involved in the nexus. Future research needs to strengthen the pool of information. It is also important to develop integrated software platforms and tools for systematic analysis of the WEF nexus. The experience made in integrated water resources management in the hydrological community, especially in the framework of Panta Rhei, is particularly well suited to take a lead in these advances. 相似文献
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ABSTRACTWe greatly enjoyed reading the paper by Liu et al., which is both timely and rich in insight, as it discusses the challenges in operationalizing the water–energy–food security (WEF) nexus. The nexus approach is gaining increasing attention, both in research and in policy documents, as reflected in the number and content of published documents in the past years and highlighted by the authors. 相似文献
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Energy and water are scarce resources and understanding the complicated energy–water nexus is an important issue for effective resource management. The purpose of this research was to analyze the competitive and cooperative relationships involving energy and water production and use. Specifically, tradeoff and integrated management of hydropower generation and water supplies are analyzed for energy–water systems. A Nash–Cournot model was established to analyze strategic behaviors among participants in energy–water systems. In the model, tradeoff analysis and integrated management of hydropower and water supplies were simulated for a reservoir system. In addition, hydropower and thermal power generation in competitive energy markets was examined. A case study of Dajia River reservoirs in the Tai-Chung and Chang-Hwa energy–water systems is presented. Dajia River is the second longest river in central Taiwan; the reservoirs system of Dajia River generates hydropower with installed capacity of 1150 MW. Strategic competitive and cooperative behaviors regarding energy–water linkage were quantified in the results. The results show that integrated management of hydropower and water supplies can increase renewable energy production, lower electricity equilibrium price, and decrease carbon dioxide emission. 相似文献
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Abstract This work makes explicit an algebraic expression giving the matrix of transient influence coefficients associated with a one-dimensional semi-confined aquifer model. The domain studied is divided into a series of connected and completely mixed compartments over which the governing equation is discretized. The discrete equations obtained are solved for the compartmental hydraulic head and used to derive the algebraic expression in question. The basic properties of the so-called algebraic influence coefficients are investigated. In particular, their consistency with the exact Green function is highlighted. Finally, the newly derived influence coefficients are applied to a simplified aquifer system in order to formulate and solve the problem of identifying illegal groundwater pumping. 相似文献
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ABSTRACTThe literature on environmental security often stresses the complementarity between sustainability and broader security goals. Less emphasis has been placed on possible trade-offs between security objectives and aspects of sustainability. This study examines the conditions under which these synergies and trade-offs are likely to occur, and how the trade-offs can be reconciled, especially during times of peacebuilding. As a case study, we analyse the effect of Israeli security concerns on environmental infrastructure designed to treat wastewater in the West Bank. This study identifies several sustainability–security trade-offs: (1) economic—in which security concerns raise costs of wastewater infrastructure, thereby crowding-out other potentially productive investments; (2) equity—in which security concerns result in disproportionate exposure of populations to environmental hazards; and (3) environmental—in which security concerns increase ecological footprints. Yet, our case study also indicates that both sides used a variety of creative measures to reconcile these trade-offs.
EDITOR D. Koutsoyiannis GUEST EDITOR K. Aggestam 相似文献
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Abstract Despite the Sahelian drought of the 1970s–1990s, the unconfined aquifer in southwest Niger exhibits a multidecadal increase in groundwater reserves. Recent changes in land surface conditions have enhanced runoff and thus indirect groundwater recharge below endorheic ponds. This paper presents a model-based investigation of surface runoff and groundwater recharge at mesoscale (～5000 km2). A new lumped-conceptual runoff model applicable to the large number of ungauged endorheic catchments is specially developed, derived from an existing fine-scale, physically-based hydrologic model. Runoff simulated for sites identified as groundwater recharge sources are used to derive recharge forcing for a Modflow-based model of the aquifer. The rising water table trend and its spatial distribution over the period 1992–2003 are generally well simulated, albeit smoothed year-to-year dynamics. Comparison with alternative methods of recharge estimation suggests, however, that there may presently exist more recharging sites and/or contributing surfaces than those considered so far. Citation Massuel, S., Cappelaere, B., Favreau, G., Leduc, C., Lebel, T. & Vischel, T. (2011) Integrated surface water–groundwater modelling in the context of increasing water reserves of a regional Sahelian aquifer. Hydrol. Sci. J. 56(7), 1242–1264. 相似文献
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The relative contributions of quasi-periodic oscillations from 2 to 35 days to the variability of foF2 at middle northern latitudes between 42°N and 60°N are investigated. The foF2 hourly data for the whole solar cycle 21 (1976–1986) for four European ionospheric stations Rome (41.9°N, 12.5°E), Poitiers (46.5°N, 0.3°E), Kaliningrad (54.7°N, 20.6°E) and Uppsala (59.8°N, 17.6°E) are used for analysis. The relative contributions of different periodic bands due to planetary wave activity and solar flux variations are evaluated by integrated percent contributions of spectral energy for these bands. The observations suggest that a clearly expressed seasonal variation of percent contributions exists with maximum at summer solstice and minimum at winter solstice for all periodic bands. The contributions for summer increase when the latitude increases. The contributions are modulated by the solar cycle and simultaneously influenced by the long-term geomagnetic activity variations. The greater percentage of spectral energy between 2 to 35 days is contributed by the periodic bands related to the middle atmosphere planetary wave activity. 相似文献
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《Water Policy》2001,3(4):321-340
Australia's annual water use of 22,000 Gl is dissected using input–output techniques, showing that 30% of Australia's water requirement was devoted to domestic food production and a further 30% to exports, compared with 7% required for direct consumption by households. There is a net annual trade deficit in embodied water of approximately 4000 Gl. A strong relationship exists between water requirement and expenditure. If by 2050 Australia's population grows to 25 million people and per-capita expenditure doubles, the annual water requirement may more than double to 50,000 Gl, equivalent to half the nation's water flows. While this increase may be improbable it gives the challenge that the water required to deliver a unit of output across the whole economy may have to reduce by a factor of two, if population growth and economic growth are to meet policy expectations. 相似文献
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《Journal of Hydrology》1999,214(1-4):91-102
The aim of the work was to quantify the role of runoff in nematode transport, compared with soil particle transport, during the rainy season in the Sudano–Sahelian area. The measurements were made at the outlet of a 58 ha watershed located in the Nioro du Rip region, south of the Senegalese peanut-growing basin. Every time the rainfall was sufficiently strong to cause a runoff, water was collected to estimate the volume of runoff, the soil particles and the nematode contents. Soils in the different agronomic areas were also collected to determine the nematode infestation. Some 6000 m3 of water run off during the rainy season, together with 18.6 t of soil and 279.5 million of nematodes, 127 million of which were major phytoparasitic species. The transport of the different species was not uniform. The first five runoff episodes supplied one-half the volume of runoff water and transported approximately half the phytoparasitic nematodes, but nearly three-quarters of the solid particles. Fifteen percent of the nematodes were transported during the intermediate stage of the rainy season, and approximately 30% during the final period, with equivalent water proportions but smaller quantities of soil. Of the 15 genera and species observed in the area, Tylenchorhynchus gladiolatus, Scutellonema cavenessi, Helicotylenchus dihystera and Gracilacus parvula represented 87% of the soil population, 61% being accounted for by the first two species. The average proportions of T. gladiolatus or G. parvula in the runoff water were greater than those in the soil, while the opposite was true for S. cavenessi, P. pseudopratensis and T. mashhoodi. H. dihystera was equally represented in both the soil and runoff water. The consequences of this “biological erosion” on the field infestation and on the cultural system based on fallowing are discussed. 相似文献
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Water retention characteristic or water retention curve (WRC) is an important constitutive feature of porous media, and also meanwhile is an indispensable requirement in hydraulic transport modelling. Previous experiments have indicated that the specific surface area of porous media has effects on the WRC. It has also been observed that a linear relationship generally exists between the air–water interface area and the water saturation within unsaturated porous media. However it seems that no detailed study on their internal linkage with the WRC has been reported yet. This paper, at first gives a review of the development of WRC modelling, then it tries to explain the water retention characteristic according to the physical and chemical behaviours of the phases involved in unsaturated porous media. Using the traditional capillary theory, the volume averaging theorem and the advances in physical chemistry of interfacial surfaces, this paper then derives out a formula which represents the water retention characteristic of porous media. This formula demonstrates the internal linkage of the WRC to the specific surface area of porosities. It also shows agreements with the experimental observations mathematically. Based on this formula, a fitting model is proposed for the static WRC of porous media. Finally, this model is tested to fit the WRC measurements of a wide range of porous materials. Comparison with other main models is presented. 相似文献
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L. N. Petrova 《Izvestiya Physics of the Solid Earth》2008,44(1):26-37
Retrospective data of monitoring under conditions of low seismic activity are used to identify free oscillations of the Earth, including the fundamental mode, the oscillation with a central period of 54 min (0 S 2 m multiplet), split into five lines with azimuthal numbers m = ?2, ?1, 0, 1, 2. It is shown that some lines of this oscillation are also recorded in atmospheric pressure variation spectra and group in ensembles of observations around frequencies predicted by the 0 S 2 m splitting theory. This phenomenon is discovered in data recorded both synchronously and in different time intervals. A causal relationship involved in the oscillation under study is determined on the basis of the examination of the direction of the acoustic energy flux. The energy flux in the region of the 0 S 2 m multiplet is shown to be directed from the Earth toward the atmosphere. This suggests that deep processes in the Earth are capable of exciting its upper shells. 相似文献
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It is doubted that the top down nature of investment planning may lead to mismatches between drinking water investment and the demands of local residents in rural China. Statistical and econometric analysis based on data of 2020 rural households from five Chinese provinces from 1998 to 2011 are used to illustrate the linkage between demand for drinking water investment and construction of drinking water projects. Household's demand significantly affects drinking water projects implemented by upper level governments and implemented jointly, but is not significant in explaining the projects implemented by village. There is evidence to suggest that the demands of local leaders override those of households in the implementation of drinking water projects provided by village in the early stage of 2005–2008. The situation improves in the latter stage of 2008–2011when the village level participatory bodies begin to provide opportunities for households to voice their preferences on public goods investment. The results of this study imply that it is important to explore appropriate regulations and policies that enabling local cadres to better meet local demands of their communities to ensure the sustainability of rural drinking water supply. 相似文献
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Soojun Kim Byung Sik Kim Hwandon Jun Hung Soo Kim 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(8):1999-2014
Water resources are influenced by various factors such as weather, topography, geology, and environment. Therefore, there are many difficulties in evaluating and analyzing water resources for the future under climate change. In this paper, we consider climate, land cover and water demand as the most critical factors affecting change in future water resources. We subsequently introduce the procedures and methods employed to quantitatively evaluate the influence of each factor on the change in future water resources. In order to consider the change in land cover, we apply the Multi-Regression approach from the cellular automata-Markov Chain technique using two independent variables, temperature and rainfall. In order to estimate the variation of the future runoff due to climate change, the data of the SRES A2 climate change scenario were entered in the SLURP model to simulate a total of 70 years, 2021–2090, of future runoff in the Han River basin in Korea. However, since a significant amount of uncertainties are involved in predicting the future runoff due to climate change, 50 sets of daily precipitation data from the climate change scenario were generated and used for the SLURP model to forecast 50 sets of future daily runoff. This process was used to minimize the uncertainty that may occur when the prediction process is performed. For future water balance analysis, the future water demand was divided into low demand, medium demand and high demand categories. The three water demand scenarios and the 50 daily runoff scenarios were combined to form 150 sets of input data. The monthly water balance within the Han River basin was then calculated using this data and the Korean version of Water Evaluation and Planning System model. As a result, the future volume of water scarcity of the Han River basin was predicted to increase in the long term. It is mostly due to the monthly shift in the runoff characteristic, rather than the change in runoff volume resulting from climate change. 相似文献
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ＧｒａｖｉｔａｔｉｏｎａｌｅｆｆｅｃｔｏｆｗａｔｅｒｃｉｒｃｕｌａｔｉｏｎｉｎｔｈｅｎｏｒｔｈｗｅｓｔＹｕｎｎａｎＭｉｎ－ＹｕＪＩＡ；（贾民育）Ｓｈａｏ－ＡｎＳＵＮ；（孙少安）Ａｉ－ＭｉｎＸＩＡＮＧ；（项爱民）ａｎｄＤｏｎｇ－ＺｈｉＬＩＵ（刘冬至）（... 相似文献
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Cao Hui He Lanfang He Zhanxiang Zhao Xiaoming 《应用地球物理》2006,3(4):248-254
High-frequency electromagnetic sounding is an electromagnetic exploration method using the natural high-frequency electromagnetic field as a field source. It has higher resolution and greater depth penetration than the direct current method and is especially fit for geothermal energy exploration and low- and mid-level groundwater detection. We introduce a successful application of high-frequency electromagnetic sounding for evaluating geothermal water resources. The high frequency electromagnetic system （MT-USA with a frequency range from 10 KHz to 1 Hz） is first applied to sample field data from China. A remote reference station is used to assure sampled data quality. We then perform 2D inversion image processing with the electrical method data. The results basically indicate the spatial distribution of underground geothermal water and provide favorable clues to finding the sources of the subsurface geothermal water in this area. 相似文献
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Data of integrated gas-geochemical studies in the 45 cruise of the R/V Akademik M.A. Lavrent’ev in July 2008 were used to study the spatial distribution of methane in the surface seawater layer, the distribution and qualitative composition of hydrocarbon gases in bottom sediments of the northwestern continental shelf, northeastern slope of Sakhalin Island, and Deryugin depression in the Sea of Okhotsk. The specific features of the methane anomalies that form in this case are considered. Tectonic faults and the distribution of oil-and-gas-bearing structures are the main factors governing the formation of hydrocarbon gas fluxes in the study area. The surface water in the entire examined area was found to be oversaturated with methane. A developed model was used to calculated methane fluxes at the water–atmosphere interface and to identify areas with maximal fluxes (up to 324 mol/(km2 day). 相似文献