Water Use Status Research Articles

Characteristics of Canopy Conductance and Environmental Driving Mechanism in Three Monsoon Climate Regions of China

Canopy conductance was an important index to measure the process of water exchange between canopy and atmosphere interface of forest ecosystem, as well as to judge the status of water use or the degree of drought stress. Therefore, the accurate estimation of forest canopy conductance was of great significance for the research of water-use efficiency. In the past, canopy conductance was measured on vegetation types in a single-point region, but there were few studies on systematic comparison in different climate zones. Based on the data sets of EC flux and conventional meteorological elements from the eddy covariance (EC) flux observation station during 2003–2010 in three typical climate zones (temperate continental monsoon climate zone, south subtropical monsoon climate zone, and mid-subtropical monsoon climate zone), Penman-Monteith model was used to calculate forest canopy conductance in different climate regions and analyze the dynamic changes of canopy conductance in different time scales. At the same time, combined with environmental factors including temperature, net radiation, soil water content, and vapor pressure deficit to explore their driving ability on the canopy conductivity of forest ecosystem in different climate regions, we finally explored the mechanism driving the canopy conductivity of forest ecosystem under different climates. The results showed that: 1) the driving ability of environmental factors in different climate regions to the canopy conductance was different, and the contribution rate of soil water content to the canopy conductance in subtropical monsoon climate zone was the largest. It was 36.01%, and the contribution rate of vapor pressure deficit to the canopy conductance in mid-subtropical monsoon climate region was the largest. It was 29.4% and the contribution rate of temperature to the canopy conductance in temperate monsoon climate region was the largest; it was 28.14%. 2). Temperature was an important factor limiting and driving canopy conductance, and there was a synergistic effect between water and temperature, which jointly drove the change in canopy conductance. 3) Environmental factors in different climate regions had threshold for the synergistic driving effect of canopy conductance. When the factors were within the appropriate threshold, the factors had a strong promoting effect on canopy conductance.

Status of water use and potential of rainwater harvesting for replacing centralized supply system in remote mountainous areas: a case study.

The failure of the centralized water supply system forced XY community to become more dependent on uncertain and unstable water sources. The results of surveying 50 households showed that 89.18% of total households depended on water collected from rivers, which contributed 58.3% of the total water volume used for the domestic demands. The average water volume consumed was 19.5 liters/person/day (l/p/d), and 86.5% of households used more than one source; 13.5% of households collected water only from rivers, and 45.94% of families had rainwater harvesting (RWH) for their activities (domestic water demand); however, RWH only provided 9.9% of total water consumption. In this study, basic methods were applied to calculate the storage tanks necessary to balance the water deficit created by drought months. Three levels of water demand (14, 20, and 30 l/p/d) can be the best choices for RWH; for a higher demand (40 and 60 l/p/d), small roof area (30-40 m2), and many people (six to seven) per family, RWH might be impractical because of unsuitable rainfall or excessively large storage tanks.

EVALUATION OF NEGATIVE ENVIRONMENTAL IMPACTS ON LAND OF AGRICULTURAL DESTINATION OF THE LVIV REGION

This article evaluates the negative impacts on agricultural land resources of the Lviv region. Among the main problems affecting agricultural land are: processes of changes in physical, chemical and mechanical characteristics of soil caused by anthropogenic activity; status of water use: discharge of untreated and insufficiently treated wastewater, as well as lack of water protection zones and coastal protection zones of water bodies; environmentally friendly collection, solid waste disposal; atmospheric air pollution, including emissions of stationary and mobile sources of harmful substances.The sources of pollution of surface and underground aquifers are the activity of mining and extraction enterprises of the region. With regard to the safe collection and disposal of solid household waste, 367 landfills with a total area of over 200 ha have been accounted for in the region. But due to the lack of necessary facilities and mechanisms, disposal technology is implemented in violation of regulatory requirements, which in turn leads to pollution of the environment. The volumes of pollutants ejected into the air on the land resources of the region decreased during the study period, but this does not reduce the negative environmental impact on the environment. In this context, the problem of environmental pollution, in particular agricultural land, is becoming an urgent obstacle to improving the quality of plant products. We propose a method for determining the amount of compensation for the degradation of the ecological function of agricultural lands caused by negative environmental impacts on them. According to this methodology, it is possible to determine and accumulate certain amounts of funds aimed at compensating for the degradation of the ecological function of land under the influence of emissions into the atmosphere.

Evaluation of water shortage crisis in the Middle East and possible remedies

AbstractWater resources in the Middle East region are becoming scarce, while millions of people already do not have access to adequate water for drinking and sanitary purposes. Water resources depletion has become a significant problem in this region that is likely to worsen. Current research by remote sensing analysis indicates a descending trend of water storage in the Middle East region, where agriculture plays a crucial role in socio-economic life. This study introduces an approach quantifying water depletion in the Middle Eastern countries, which are being challenged in the management of their water resources. Furthermore, this paper presents results of a survey assessing the status of water use and supply in Middle Eastern countries and outlines some potential remedies. Specifically, Iran's water use is evaluated and compared with its neighbors'. The water equivalent anomaly (WEA) and total water storage (TWS) depletion are two indexes of water scarcity calculated for Middle Eastern countries surveyed herein. Our analysis reveals that Lebanon, Syria, Iraq, and Iran are countries with very negative water scarcity indexes. These estimates prove that international cooperation is needed to manage available regional water resources and reverse depletion of natural water sources. It is demonstrated herein that virtual water trade can help remediate regional water shortage in Middle Eastern countries.

Water use and demand forecasting model for coal-fired power generation plant in China

China is planning to expand its coal power generation to meet its energy demand and support the economic development. The current level of water use for thermal power generation is 8% of total water use, China is a water-stressed country which is facing many new challenges including climate change and population growth. China’s future coal power industry will add further pressures on already stressed water resources. This raised the key question on how the limited water resources can be managed to meet the demand of planned coal power expansion. A great level of understanding on the present status of water use and forecasting future demand in coal power plant is very important to answer this question. However, knowledge gap, data availability and accessibility are the major challenge in this regard. This paper attempts to improve the knowledge of the water demand in the coal power generation plant in China by using a simple water use model. Furthermore, a method is proposed to forecast future water demand in coal power plant. The proposed method is applied for forecasting water demand in Shaanxi coal power bases in Northern China under four scenarios. The results showed that the future water demand for Shaanxi coal power base will increase by 102–161% compared to current use under different scenarios in order to increase the production capacity by 206%. Adopting the optimum level of current status of water use, it is possible to limit the increase in water demand by 102% or 47.119 million-m3. It is expected that the finding of the study would help decision-making processes in water resources management in Chinese coal power generation.

Water use in the transboundary basin of the Amur river

This paper summarizes the problems and consequences associated with water use in the Russian and Chinese parts of the Amur river basin. Taking into consideration the set of indicators involving the water withdrawal, the utilization of source water, the volumes of recirculated and repeated-consecutive water supply, the volumes of waste waters, the capacity of pollution control facilities, etc., an outline is given of the present status of water use in the national parts of the basin. The future amounts of water consumption are forecasted, and it is shown how it will increase in the Russian as well as the Chinese parts. An analysis of the spatiotemporal dynamics of water-use indicators revealed the differently directed tendencies in the water-use pattern in the Russian and Chinese parts of the Amur river basin, and the existence of quantitative disproportions caused by a different degree of development and a different intensity of economic growth. In the Russian part of the basin, the amounts of water used have stabilized in recent years after a decrease, whereas they are increasing steadily in the Chinese and Russian parts where the highest proportion of water is used to meet agricultural and production needs, respectively. It is shown that water use, the density of the water-economy structure and the discharges of pollutants in the Chinese part of the basin are larger by factors of several tens than those in the Russian part. The manufacture of water-intensive industrial products and the load of agriculture on water resources also differ by factors of several tens. The indicator of population size is used to characterize the degree of development of the basin’s territory. For the Russian part of the basin the study revealed a dependence of water consumption on the population size and on the volumes of water-intensive products in the production facilities with a low coefficient of recirculated water use. This dependence can also be extended to the Chinese part where circulated water supplies are being used only moderately.

The Upper Orange River Water Resources Affected by Human Interventions and Climate Change

The major problem in the study area is the unlawful water abstractions for irrigation use. In South Africa, indications show that about 240 million m3/a of illegal water use is due to unauthorised withdrawals or violations of water use licenses. The status of water use for irrigation in the Orange-Senqu Basin also shows that insufficient information exists such that work needs to be done to understand the potential for increased efficiency of water use, taking into account issues pertaining to crop type, soil type and technological options. Studies like this one could also shed light on the potential impact of climate change on water use in the basin as this area may well experience significant impacts from rising temperatures and changing rainfall patterns. The processes of validation and verification will determine the extent of existing lawful water use. The use of remote sensing techniques (satellite, aerial photographs, etc.) could be employed to determine if the volume of water use registered by irrigators is accurate, i.e. valid and that the volume of water use registered is lawful (verification). Currently, ecological requirements for the river mouth are met through releases from Vanderkloof Dam and amount to just 290 million m3/a. However several recent studies including the Gesellschaft fur International Zusammenarbeit - Integrated Water Resources Management (GIZ – IWRM) study highlight that this is based on a fairly outdated methodology. The more recent Lower Orange Management study found a high level estimate of ecological requirements to be in order of 1 062 million m3/a.

Water in life cycle assessment—50th Swiss Discussion Forum on Life Cycle Assessment—Zürich, 4 December 2012

Water use, its impacts and management, have become a focus of attention in the past decade in the context of climate change and increasing consumption (in particular of food and agricultural products) due to a growing global population. Many efforts have been made to include water-related issues in life cycle assessment (LCA) in various ways, from the long-standing eutrophication, acidification, and ecotoxicity methods, to the more recent water consumption aspects. Four years on from the first discussion forum on water in LCA (35th Swiss Discussion Forum on LCA, Zürich, 5 June 2008), numerous developments have occurred, resulting in a rich palette of approaches. Significant challenges still remain, related to the complexity of water systems and ecosystems, and certain impacts are still not considered. New challenges have emerged, such as how to fit these “pieces” together to form a coherent and comprehensive approach for assessing the impacts of water use (both degradative and consumptive). Practice has started to apply certain water consumption-related approaches and an early feedback between practitioners and developers is essential to ensure a harmonious further development. The 50th Swiss Discussion Forum on Life Cycle Assessment (DF-50) gave a brief overview of the current status of water use in LCA, and then focused on the following topics in three main sessions: (1) a selection of recent research developments in the field of impact assessment modeling; (2) identification of new and remaining challenges where future effort could be concentrated, with a focus on spatial and temporal resolution; (3) and experiences and learnings from application in practice. Furthermore, several short presentations addressed the issues of inventory requirements and comparison of impact assessment approaches. The DF-50 was concluded with a discussion workshop, focusing on four issues: which degree of regionalization is desirable, how to address data gaps in inventories, the comparability of different impact assessment approaches, and the pros and cons of including positive impacts (benefits). Numerous recent developments in life cycle impact assessment have tackled impact pathways, spatial and temporal resolutions, and uncertainties. They have lead to an increase of the completeness of impact assessment, but also of its complexity. Although developments have also occurred in inventories, the gap between impact assessment and inventory is challenging, which in turn limits the applicability of the methods. Regionalization is confirmed as an essential aspect in water footprinting; however, its implementation requires concerted effort by impact assessment developers and software developers. Therefore, even though immense progress has been made, it may be time to think of putting the pieces together in order to simplify the applicability of these tools: enabling the support of improvements in companies and policy is the ultimate goal of LCA. The recordings and presentations of the DF-50 are available for download from www.lcaforum.ch.