水资源的持续开发和利用

随着人品的增长和经济的发展,越来越多的国家正面临着严重的水危机、水质的恶化和水生态系统的破坏使许多国家的淡水供应出现危机,所以水资源必须得到保护和合理的开发。本文探讨了全球水资源的短缺及其原因,并提出了解决水资源短缺的途径。     

Climate Change and Water Resources in Arid Mountains: An Example from the Bolivian Andes

Climate change is projected to have a strongly negative effect on water supplies in the arid mountains of South America, significantly impacting millions of people. As one of the poorest countries in the region, Bolivia is particularly vulnerable to such changes due to its limited capacity to adapt. Water security is threatened further by glacial recession with Bolivian glaciers losing nearly half their ice mass over the past 50 years raising serious water management concerns. This review examines current trends in water availability and glacier melt in the Bolivian Andes, assesses the driving factors of reduced water availability and identifies key gaps in our knowledge of the Andean cryosphere. The lack of research regarding permafrost water sources in the Bolivian Andes is addressed, with focus on the potential contribution to mountain water supplies provided by rock glaciers.     

Water resources vulnerability assessment in the Adriatic Sea region: the case of Corfu Island

Cross-border water resources management and protection is a complicated task to achieve, lacking a common methodological framework. Especially in the Adriatic region, water used for drinking water supply purposes pass from many different countries, turning its management into a hard task to achieve. During the DRINKADRIA project, a common methodological framework has been developed, for efficient and effective cross-border water supply and resources management, taking into consideration different resources types (surface and groundwater) emphasizing in drinking water supply intake. The common methodology for water resources management is based on four pillars: climate characteristics and climate change, water resources availability, quality, and security. The present paper assesses both present and future vulnerability of water resources in the Adriatic region, with special focus on Corfu Island, Greece. The results showed that climate change is expected to impact negatively on water resources availability while at the same time, water demand is expected to increase. Water quality problems will be intensified especially due to land use changes and salt water intrusion. The analysis identified areas where water resources are more vulnerable, allowing decision makers develop management strategies.     

Burning Water: A Comparative Analysis of the Energy Return on Water Invested

While various energy-producing technologies have been analyzed to assess the amount of energy returned per unit of energy invested, this type of comprehensive and comparative approach has rarely been applied to other potentially limiting inputs such as water, land, and time. We assess the connection between water and energy production and conduct a comparative analysis for estimating the energy return on water invested (EROWI) for several renewable and non-renewable energy technologies using various Life Cycle Analyses. Our results suggest that the most water-efficient, fossil-based technologies have an EROWI one to two orders of magnitude greater than the most water-efficient biomass technologies, implying that the development of biomass energy technologies in scale sufficient to be a significant source of energy may produce or exacerbate water shortages around the globe and be limited by the availability of fresh water.     

Hydrologic monitoring tools for freshwater municipal planning in the Arctic: the case of Iqaluit,Nunavut, Canada

Freshwater and the services it provides are vital to both natural ecosystems and human needs; however, extreme climates and their influence on freshwater availability can be challenging for municipal planners and engineers to manage these resources effectively. In Arctic Canada, financial and human capital limitations have left a legacy of freshwater systems that underserve current communities and may be inadequate in the near future under a warming climate, growing population, and increasing demand. We address this challenge to community water resource planning by applying several novel water supply forecasting methods to evaluate the Apex River as an alternative freshwater source for Iqaluit, Nunavut (Canada). Surveys of water isotope composition of the Apex River and tributaries indicated that rainfall is the main source of water replenishment. This information was utilized to calibrate a water resource assessment that considered climate forecasting scenarios and their influence on supply, and alternative scenarios for freshwater management to better adapt to a changing climate. We found that under current climate and demand conditions, the freshwater supply of Iqaluit would be in a perpetual state of drawdown by 2024. Analysis of current infrastructure proposals revealed significant deficiencies in the supply extensions proposed whereby the Apex replenishment pipeline would only provide a 2-year extension to current municipal supply. Our heuristic supply forecast methods allowed for several alternative supply strategies to be rapidly evaluated, which will aid the community planning process by specifically quantifying the service life of the city’s current and future primary water supply.     

Avoiding conflicts over Africa's water resources

Some 85% of Africa's water resources are comprised of large river basins that are shared between several countries. High rates of population growth accompanied by continued increases in the demand for water have resulted in several countries passing the point where the scarcity of water supplies effectively limits further development. Present population trends and patterns of water use suggest that more African countries will exceed the limits of their economically usable, land-based water resources before 2025. Normally, water allocation and distribution priorities within a country are aligned with national development objectives. While this may achieve national "water security" objectives, greater emphasis needs to be placed on regional efforts to ensure that the available water resources are used to derive sustainable long-term benefits for the peoples of Africa as a whole. Ideally, each country's water-resource management strategy needs to be aligned with that of its neighbors if peace and prosperity are to be maintained and conflict is to be avoided in the region.     

Effects of golf course construction and operation on water chemistry of headwater streams on the Precambrian Shield

To investigate the effects of golf course construction and operation on the water chemistry of Shield streams, we compared the water chemistry in streams draining golf courses under construction (2) and in operation (5) to streams in forested reference locations and to upstream sites where available. Streams were more alkaline and higher in base cation and nitrate concentrations downstream of operational golf courses. Levels of these parameters and total phosphorus increased over time in several streams during golf course construction through to operation. There was evidence of inputs of mercury to streams on two of the operational courses. Nutrient (phosphorus and nitrogen) concentrations were significantly related to the area of unmanaged vegetation in a 30 x 30 m area on either side of the sampling sites, and to River Bank Quality Index scores, suggesting that maintaining vegetated buffers along the stream on golf courses will reduce in-stream nutrient concentrations.     

Assessing the impacts of globalization and gender parity on economic growth: empirical evidence from OIC countries

The contemporary debate on globalization and gender equality has a strong impact on economic growth. The present study analyzes the impacts of globalization and gender parity on economic growth in the Organization of Islamic Cooperation (OIC) 47 member countries for the period (1991–2017), using System GMM panel data technique. The results of system GMM have also been empirically estimated by making two groups (viz., low-income and high-income OIC member countries from the World Bank data classification, 2019) to examine the robustness of globalization and gender parity on economic growth. The results reveal that there is a negative impact of globalization on economic growth in the overall sample of OIC countries. When estimated by decomposing low-income countries and high-income countries, globalization has a significantly positive impact on economic growth in the case of high-income OIC countries, whereas globalization slashes GDP in the case of low-income OIC countries. The study finds that there is a positive impact of gender parity (ratio of female to male labor force work participation) on economic growth. Moreover, foreign remittances, government expenditures, capital formation, and human capital are also becoming the causes of a significant increase in economic growth in OIC member countries.     

Contamination levels of selected organochlorine and organophosphate pesticides in the Selangor River, Malaysia between 2002 and 2003

In Malaysia, rivers are the main source of public water supplies. This study was conducted from 2002 to 2003 to determine the levels of selected organochlorine and organophosphate pesticides in the Selangor River in Malaysia. Surface water samples have been collected seasonally from nine sites along the river. A liquid-liquid extraction followed by gas chromatography-mass spectrometry technique was used to determine the trace levels of these pesticide residues. The organochlorine pesticides detected were lindane, heptachlor, endosulfan, dieldrin, endosulfan sulfate, o,p'-DDT, p,p'-DDT, o,p'-DDE and p,p'-DDE whereas for organophosphate pesticides, they were chlorpyrifos and diazinon. At the river upstream where a dam is located for public water supply, incidents of pesticide levels exceeding the European Economic Community Directive of water quality standards have occurred. Furthermore, the wetland ecosystems located at the downstream of the river which houses the fireflies community is being threatened by occasional pesticide levels above EPA limits for freshwater aquatic organisms. The occurrence of these residual pesticides in the Selangor River can be attributed to the intense agriculture and urban activity.     

Assessing the effects of tertiary treated wastewater reuse on the presence emerging contaminants in a Mediterranean river (Llobregat,NE Spain)

Purpose  

The Llobregat River, which is characterized by important fluctuations of the flow rates, receives treated waters from WWTPs. During the years 2007 and 2008, the Llobregat River basin suffered from a severe drought which affected the supply of drinking water facilities (DWF) that rely on the exploitation of the river water. The Catalan Water Agency implemented a water reuse experiment with the objective of maintaining the river flow rate at sufficiently high level so as to ensure the supply of raw water to Barcelona’s major DWF.     

Testing the Established Hydrogeologic Model of Source Water to the Amargosa River Basin,Inyo and San Bernardino Counties,California

The current conceptual hydrogeologic model established for source water to the Amargosa River was tested in order to help inform management decisions regarding the Amargosa River's Federal designation as Wild and Scenic through an Act of Congress. The limited availability of water in this region results in the critical need for effective management in the basin to maintain its Wild and Scenic attributes inclusive of habitat for several endangered and threatened species. The use of forensic tools and integration of multiple lines of geologic, hydrogeologic, geochemical, and stable isotopic evidence suggest that the simple historical model for primary groundwater transport through this region is incorrect and that a large supply of regional baseflow does not provide the hydrogeological foundation of the Amargosa River basin. Data collected is consistent with an alternative model requiring complex source mixing and shallow alluvial groundwater that supports river flow. This conclusion also suggests Wild and Scenic conditions in this basin are more precarious than previously understood.     

MTBE in California Drinking Water: An Analysis of Patterns and Trends

Over the past decade, there has been much publicity surrounding the impact of Methyl tert -butyl ether (MTBE) on drinking water supplies in the United States. In California, the presence of MTBE in groundwater and drinking water has led to a ban on the future use of MTBE in gasoline. Other states, such as those in the northeast, are also seeking ways to reduce or eliminate the use of MTBE due to perceived threats to the environment and public health. Despite claims about the incidence of MTBE in drinking water, no comprehensive characterization has been conducted on the available drinking water monitoring data. This paper provides a detailed analysis of the MTBE drinking water data compiled by the California Department of Health Services (CDHS) from 1995 to 2000. We find that MTBE was detected in about 1.3% of all drinking water samples, 2.5% of drinking water sources, and 3.7% of drinking water systems in California over this 6-year period. Our analysis reveals that many drinking water sources are not sampled routinely for MTBE, and in those sources that appear to be affected by MTBE, the compound is not consistently detected. The majority of MTBE detections are also concentrated in several geographic areas, which contain about 9-21% of the total California population. Average detected MTBE concentrations have decreased significantly since 1995 and 1996, ranging from 5 to 15 ppb over the last 3 years depending on the outcome of interest. Of the samples in which MTBE was present above the analytical detection limit, the concentrations in approximately 73% of drinking water samples and 86% of drinking water sources and systems were below the State's primary health-based standard of 13 ppb. Our findings suggest that, although some drinking water supplies in California have been affected by MTBE, the majority of drinking water sources and systems either have not been affected at all or contain MTBE at concentrations below levels that are likely to be of health concern.     

Fate of ϵ-caprolactam in the aquatic environment

The rate and extent of ?-caprolactam degradation in aquatic systems are dependent on the nutrient availability, indigenous microbial population and activity, chemical concentration, and water temperature. The labeled chemical evolved ¹⁴CO₂ indicating ring cleavage with between 35 and 80% of the radioactivity evolved as ¹⁴CO₂ after 21 days in yeast extract-supplemented waters. The percent of caprolactam degraded was indirectly related to the chemical's concentration in the water, suggesting microbial inhibition at high caprolactam concentrations.     

Review of Singapore's air quality and greenhouse gas emissions: current situation and opportunities

Singapore has many environmental accomplishments to its credit. Accessible data on air quality indicates that all criteria pollutants satisfy both U.S. Environmental Protection Agency (EPA) and World Health Organization (WHO) air quality standards and guidelines, respectively. The exception is PM2.5 (particles with an aerodynamic diameter < or = 2.5 microm), which is not currently considered a criteria pollutant in Singapore but may potentially be the major local air pollution problem and cause for health concern. Levels of other airborne pollutants as well as their physical and chemical processes associated with local formation, transformation, dispersion, and deposition are not known. According to available emission inventories, Singapore contribution to the total atmospheric pollution and carbon budget at the regional and global scales is small. Emissions per unit gross domestic product (GDP) are low compared with other countries, although Singapore's per-capita GDP and per-capita emissions are among the highest in the world. Some information is available on health effects, but the impacts on the ecosystem and the complex interactions of air pollution and climate change at a regional level are also unknown. This article reviews existing available information on atmospheric pollution and greenhouse gas emissions and proposes a multipollutant approach to greenhouse gas mitigation and local air quality. Singapore, by reducing its per-capita emissions, increasing the availability of information (e.g., through regularly publishing hourly and/or daily PM2.5 concentrations) and developing a research agenda in this area, would likely be seen to be a model of a high-density, livable, and sustainable city in Southeast Asia and other tropical regions worldwide.     

Towards saving freshwater: halophytes as unconventional feedstuffs in livestock feed: a review

Water represents 71% of all earth area and about 97% of this water is salty water. So, only 3% of the overall world water quantity is freshwater. Human can benefit only from 1% of this water and the remaining 2% freeze at both poles of earth. Therefore, it is important to preserve the freshwater through increasing the plants consuming salty water. The future prosperity of feed resources in arid and semi-arid countries depends on economic use of alternative resources that have been marginalized for long periods of time, such as halophytic plants, which are one such potential future resource. Halophyte plants can grow in high salinity water and soil and to some extent during drought. The growth of these plants depends on the contact of the salted water with plant roots as in semi-desert saline water, mangrove swamps, marshes, and seashores. Halophyte plants need high levels of sodium chloride in the soil water for growth, and the soil water must also contain high levels of salts, as sodium hydroxide or magnesium sulfate. There are many uses for halophyte plants, including feed for animals, vegetables, drugs, sand dune stabilizers, wind shelter, soil cover, wetland cultivation, laundry detergents, and paper production. This paper will focus on the use of halophytes as a feed additive for animals. In spite of the good nutritional value of halophytes, some anti-nutritional factors as nitrates, nitrite complexes, tannins, glycosides, phenolic compounds, saponins, oxalates, and alkaloids may be present in some of them. The presence of such anti-nutritional agents makes halophytes unpalatable to animals, which tends to reduce feed intake and nutrient use. Therefore, the negative effects of these plants on animal performance are the only objection against using halophytes in animal feed diets. This review article highlights the beneficial impact of considering halophytes in animal feeding on saving freshwater and illustrates its nutritive value for livestock from different aspects.     

Agriculture as Provider of Both Food and Fuel

A database of global agricultural primary production has been constructed and used to estimate its energy content. The portion of crops available for food and biofuel after postharvest losses was evaluated. The basic conditions for agriculture and plant growth were studied, to ensure sustainable scenarios regarding use of residues. The available energy contents for the world and EU27 was found to be 7,200–9,300 and 430 TWh, respectively, to be compared with food requirements of 7,100 and 530 TWh. Clearly, very little, or nothing, remains for biofuel from agricultural primary crops. However, by using residues and bioorganic waste, it was found that biofuel production could theoretically replace one-fourth of the global consumption of fossil fuels for transport. The expansion potential for global agriculture is limited by availability of land, water, and energy. A future decrease in supply of fossil energy and ongoing land degradation will thus cause difficulties for increased biofuel production from agriculture.     

Assessing the effects of tertiary treated wastewater reuse on a Mediterranean river (Llobregat,NE Spain), part III: pathogens and indicators

Purpose  

Need, coupled with advances in water treatment technology, is motivating a growing interest in augmenting drinking water supplies with reclaimed water. Using reclaimed water to increase the flow of the Llobregat River upstream the water catchment site of the complex multi-step drinking water treatment plant of Sant Joan Despí has been considered. The impact of reclaimed water discharges on the load of E. coli, spores of sulphite-reducing clostridia, somatic coliphages, cytopathogenic enteroviruses, and total and infectious Cryptosporidium oocysts in the Llobregat River water was assessed to gain information for funded decisions in potential future emergencies.     

多水源供水管网中铁释放规律

针对水源切换而引起的水质超标现象,开展了多水源联合供水条件下管网中铁释放规律的研究。分析了北方某城市2种水源(滦河水和长江水)的水质特点,利用实验模拟反应器分别研究了水源完全置换和供水分界线处水源混合区域的铁释放规律。结果表明,多水源供水管网的铁释放速率与水源水质密切相关,特别是水中含高浓度SO2-4和氯化物时会加快铁的释放。不同水源之间的频繁切换会破坏管垢表面的钝化层,使铁释放速率迅速变化,随后会有所缓解,但新的平衡的形成需要较长时间。供水分界线处的水源混合区域,由于水质的不断变化造成管垢表面很难形成稳定的钝化层,铁释放速率持续偏高,只有当长江水所占比例高达75%以上时才能得到抑制。     

Biological solubilization and mineralization as novel approach for the pretreatment of food waste

The performance of a garbage disposal system to solubilize and mineralize food wastes through biological solubilization was evaluated through the examination of the effects of operational conditions like water supply volume, water supply frequency and aeration on the amount of waste solubilized, mineralized and accumulated in the reactor. The biological solubilization process consisted of a solubilization reactor and a circulation tank. Food waste and fresh water were supplied into the solubilization reactor with support media. Wastewater from the solubilization reactor was discharged to the circulation tank and water in the circulation tank was periodically pumped back to the solubilization reactor. In case of the total food waste loading of 16 kg m(3-1) d(-1), little carbon (0-5.7%) accumulated in the reactor as long as the system was kept under aerobic condition through large volume of water supply (higher than 3.5 lh(-1)) or applying aeration in the circulation tank. However, 42% of the loaded carbon accumulated under anaerobic condition in low water supply (less than 1.8 lh(-1)). The rest of the waste was either solubilized or mineralized. The aeration in the circulation tank, therefore, was effective to provide similar solubilization and mineralization as the large volume of water supply. However, frequency of feeding at the large volume of water supply had no significant effect on the amount of waste solubilization and mineralization.     

Microbiological risk assessment of Agios Georgios source supplies in Northwestern Greece based on faecal coliforms determination and sanitary inspection survey

The assessment of potential risks from microbiological contamination of drinking water supplies is of greatest concern to human health. The study involves the examination of water samples from Agios Georgios source that supplies the capitals, the major towns and several villages of Arta, Preveza and Lefkada prefectures, in Northwestern Greece. The study includes the sanitary inspection survey of the source and the microbiological examination of water samples on a monthly basis during the period February 1996-June 1999 except of Augusts (n=38). The microbiological risk assessment (MRA) approach of World Health Organisation (WHO) guidelines was applied to enhance the source protection. The faecal contamination of the source water was quantified using faecal coliforms (FC) as indicator bacteria. Microbiological analyses indicate that of the 38 samples analyzed the FC failure rate (positive samples) was 63.2% according to the limit set by the 98/83 directive of the European Union. The 36.8% of the source water samples was found in conformity with WHO guidelines, 42.1% of low risk, 21.1% of intermediate risk while there was not found samples of high or very high risk. Failure rates displayed a seasonal trend being greater during the winter, decreased during spring and autumn and lower during summer. This observation was explained partially by a significant positive relationship with the rainfall amount (r(Spearmann)=0.890, P=0.001). The sanitary inspection score was found 5/10 during the whole survey period that corresponds to an intermediate risk of source contamination. The color-code classification for FC contamination was found 36.8% A (blue, no risk), 42.1% B (green, low risk) and 21.1% C (yellow, intermediate risk). The previous risks were combined for the assessment of waterborne risk, which was determined as intermediate to high; therefore there is a need for high action priority. The potential remedial actions were also suggested in order to improve the source protection of such supplies.