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Polycyclic aromatic hydrocarbons (PAHs) and their oxygen-containing derivatives (OPAHs) in soils from the Angren industrial area, Uzbekistan 总被引:1,自引:0,他引:1
Benjamin A. Musa Bandowe Michael Kersten 《Environmental pollution (Barking, Essex : 1987)》2010,158(9):2888-2899
We measured the concentrations and depth distribution (0-10, 10-20 cm) of 31 PAHs and 12 OPAHs in soils at eleven equidistant sampling points along a 20-km transect in the Angren industrial region (coal mine, power plant, rubber factory, gold mine), Uzbekistan to gain an insight into their concentrations, sources, and fate. Concentrations of all compounds were mostly much higher in the 0-10 cm than in the 10-20 cm layer except in disturbed soil close to the coal mine. Proximity to one of the industrial emitters was the main determinant of PAH and OPAH concentrations. The ∑31PAHs concentrations correlated positively with the ∑7 carbonyl-OPAH (r = 0.98, p < 0.01), ∑5 hydroxyl-OPAH (r = 0.72, p < 0.05), and with industrially emitted trace metals in the topsoil, identifying industrial emissions as their common source. Concentrations of several OPAHs were higher than their parent PAHs, but their vertical distribution in soil suggested only little higher mobility of OPAHs than their corresponding parent PAHs. 相似文献
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Anna‐Katharina Hornidge Lisa Oberkircher Bernhard Tischbein Gunther Schorcht Anik Bhaduri Ahmad M. Manschadi 《Natural resources forum》2011,35(4):251-268
The Khorezm region is located in the northwest of Uzbekistan, approximately 350 km from the current shore of the Aral Sea. It comprises a large‐scale irrigation system that conveys water from the river Amu Darya to agricultural land cropped mainly with cotton, wheat, and rice. Khorezm's water resources are vulnerable as they depend on upstream developments and are indispensable to rural livelihoods and state budgets. Since water scarcity is expected to increase in the future, sustainable water management is a necessity. Hence, the objectives of the paper are to: (1) conceptualize the distinctive features of water management in Khorezm; (2) provide an integrated analysis of water management by establishing linkages between society, technical infrastructure, and the bio‐physical environment; and (3) make policy and technology recommendations for improved water management. To conceptualize water management in Khorezm, the paper distinguishes three types of practices: formal practices, strategic practices, and discursive practices. Based on these, it presents an analysis of water management on the state water management level, the water user association level, and the farmer and field level. For each level, recommendations are given. The paper concludes that elements of integrated water resources management (IWRM) such as transparency, accountability, participation, and technical efficiency are relevant to improve water management in Khorezm, as elsewhere. In addition, it underlines the need to create legal space for agency and innovation. Technical tools such as models are increasingly important for facilitating transparency and enabling agents to access and make use of information across the management hierarchy. 相似文献
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In this paper, we assess the physical dimensions of Uzbekistan's economy during 1992–2011 by using the economy-wide material flow analysis (EW-MFA) method, which is an internationally recognized tool for such assessments. There have been a number of studies using methodological standardization of EW-MFA, but to the best of our knowledge, it has never been used to assess the metabolism of Central Asian economies, especially, in this case, the Republic of Uzbekistan.Our analysis strives to empirically evaluate macroscopic economic activities by considering the accounting of material flows. The material flows data-set comprises of consistent data for domestic extraction, imports, and exports, as well as other derived MFA-based indicators.The derived indicators are internationally compared for further evaluation of national economic development performance in a given period. The indicators of direct material input (DMI) and total material requirements (TMR) showed a slight increase in 1992–2011 with an average annual increase of 2.79% and 2.34%. The trends of TMR, DMI, domestic material consumption (DMC) and material efficiency, which is indicated by GDP/DMI, displayed lower values than other industrialized countries referenced in the international comparison. Although national economic performance data showed particularly remarkable success, indicators measuring material inputs and DMC reveal an insignificant increase during the period of study. During the second decade of study period, relative decoupling has occurred which indicated that the economic indicator (GDP) grows faster than DMC and other macro indicators grow. 相似文献
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The irrigation sector constitutes the backbone of Uzbekistan's economy, providing social and economic stability in the region. The sector collapsed with the fall of the Soviet Union, due to worsening of infrastructure conditions causing tensions among resource users. Subsequent irrigation management reforms were implemented in a top-down manner. More than a decade after the initial reforms – which established local Water Consumers Association (WCA) and transferred operation and maintenance responsibilities for on-farm irrigation canals – the poor performance of these associations is still apparent, illustrating the heritage of the strong role of state agencies in Uzbek water management that still affects collective irrigation management today. This paper identifies the necessary and sufficient conditions for successfully managing common pool resources (CPRs) and, more specifically, irrigation canal maintenance in the rural Bukhara region of Uzbekistan. Fifteen WCAs were examined regarding conditions that may facilitate successful irrigation canal maintenance. Methods involved focus group discussions and in-depth interviews with the associations concerned. Data gathered was analyzed using fuzzy-set qualitative comparative analysis. The results indicate that two paths of local factors can lead to well-maintained irrigation canals: (1) the combination of appropriate chairmanship skills with sustainable resource appropriation or (2) the combination of appropriate chairmanship skills with the presence of effective participatory governance. The results also illustrate the role of path-dependence and traditional co-production of irrigation management in Uzbekistan. 相似文献
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Climate change, land degradation and drought affect millions of people living in drylands worldwide. With its food security depending almost entirely on irrigated agriculture, Central Asia is one of the arid regions highly vulnerable to water scarcity. Previous research of land and water use in the region has focused on improving water-use efficiency, soil management and identifying technical, institutional and agricultural innovations. However, vulnerability to climate change has rarely been considered, in spite of the imminent risks due to a higher-than-average warming perspective and the predicted melting of glaciers, which will greatly affect the availability of irrigation water. Using the Khorezm region in the irrigated lowlands of northwest Uzbekistan as an example, we identify the local patterns of vulnerability to climate variability and extremes. We look at on-going environmental degradation, water-use inefficiency, and barriers to climate change adaptation and mitigation, and based on an extensive review of research evidence from the region, we present concrete examples of initiatives for building resilience and improving climate risk management. These include improving water use efficiency and changing the cropping patterns that have a high potential to decrease the exposure and sensitivity of rural communities to climate risks. In addition, changes in land use such as the afforestation of degraded croplands, and introducing resource-smart cultivation practices such as conservation agriculture, may strengthen the capacity of farmers and institutions to respond to climate challenges. As these can be out-scaled to similar environments, i.e. the irrigated cotton and wheat growing lowland regions in Central Asia and the Caucasus, these findings may be relevant for regions beyond the immediate geographic area from which it draws its examples. 相似文献
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Water quantity and quality dynamics of the THC — Tuyamuyun Hydroengineering Complex — And implications for reservoir operation 总被引:2,自引:0,他引:2
Froebrich J Bauer M Ikramova M Olsson O 《Environmental science and pollution research international》2007,14(6):435-442
Background In the Aral Sea basin, safe water resources are scarce and steadily becoming scarcer. Particularly high quality water is going
to become a rare good.
The object of the study was the Tuyamuyun Hydroengineering Complex (THC), a complex of artificial water reservoirs located
in the lower Amu Darya River, which provides water for irrigation, industry, and drinking for the lower Amu Darya region.
The focus was on operation of one of its four reservoirs, the Kaparas, which is mainly used for drinking water supply. The
objective includes the investigation of impacts of conventional operation schemes on the reservoir water quality for improving
drinking water quality (salinity). Basic operation rules for Kaparas, which can be considered as representative for conventional
dam operation under dry year conditions, had to be identified and improved operation schemes derived.
Methods Existing data archives were analysed, and further data were acquired from field surveys, data processing and modelling studies.
Historical data were identified, which are appropriate to determine representative schemes for the conventional operation.
For the simulation of time-dependent and depth-dependent changes of reservoir salinisation, the reservoir water quality model
Lac was used and linked with the THC model.
Results and Discussion Modelling results for the simulation of temperature dynamics and density stratification showed a sufficient congruence with
the measured temperature profiles. The conformity of measured and calculated salt concentration is basically ensured. The
reservoir, which fill with higher saline water at the end of the summer, aggravates the entrainment of high saline water in
the entire water column.
Conclusions The current conventional operation regime mainly leads to filling the Kaparas reservoir with high saline water during the
winter months. Even in the event of starting with comparable low salinity levels, the simulation demonstrates the rapid deterioration
of the reservoir water quality. Under dry year conditions, the WHO standards for drinking water will be exceeded by 30% after
two years, so that the impact of dry years in the context of water stress becomes visible.
Recommendations and Outlook Processed data and results are now available to identify enhanced reservoir operation strategies for salinity reduction by
changing the period of reservoir filling and release, as well as to initiate a detailed analysis of how water deficits in
dry years may be reduced by improved operation regimes. Using adapted and enhanced operation rules for THC reservoirs, the
local population within the lower Aral Sea basin might be supplied with more potable water of higher quality in future. 相似文献
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Water Security in Uzbekistan: Implication of Return Waters on the Amu Darya Water Quality 总被引:1,自引:0,他引:1
Crosa G Stefani F Bianchi C Fumagalli A 《Environmental science and pollution research international》2006,13(1):37-42
- DOI: http://dx.doi.org/10.1065/espr2006.01.007
Goal, Scope and Background Amu Darya river, one of the main water resources of Uzbekistan, shows a relevant longitudinal enrichment of soluble contents
which strongly limits the human uses of its waters. Because of the low natural run-off processes, salts and pollutants are
mainly driven to the river by the return waters used for washing and irrigating the surrounding lands. The influence of return
waters on stream quality is dramatically relevant in the lower reaches of the river where almost all the flowing waters have
been previously used for the agriculture practises. To provide analytical evidence on the potential effects of return waters
on the quality of the Amu Darya river, the paper reports and comments data on salinity and metals contents of the waters flowing
in the artificial channel network of Bukhara and in the Amu Darya river, from Bukhara up to the dam forming the Tuyamuyn Hydro
Complex (THC).
Methods A total of 15 sampling sites were selected for the analytical survey: Two sites were located on the Amu Darya river downstream
from the inflow of the return waters from Bukhara, two in the river entering in the THC, and three downstream from the dam
forming the reservoir complex. The waters entering and leaving the Bukhara agricultural area were sampled in two main collectors,
while the waters flowing in the channel system were sampled in six distinct collectors. The following parameters were considered
in the survey: pH, Oxygen, Hardness, Salinity, Conductivity, P-PO4 3–, P tot, N tot, N-NO3 2–, N-NO2 –, COD, Ca2+, Mg2+, Fe,
Mn, Zn, Cr, Cu, Ni, Cd, Pb.
Results and Discussion Salt concentrations below 1000 mg/l were measured in the Amu Darya waters upstream to Bukhara. In the drainage system, salinity
exceeds the palatability limit and reaches the maximum peak of 3200 mg/l in the outflow collector. Due to dilution effects,
salinity returns to lower values (400–700 mg/l) along the Amu Darya river downstream from Bukhara; calcium and magnesium resulted
the major constituents of the overall salinity. No serious metal contaminations were detected in the waters entering and leaving
the examined channel system. Differently, the Amu Darya waters upstream to the THC showed a relevant metal contamination,
with Cr, Ni, Fe concentrations exceeding the limits for human consumption. In the downstream sites, located in the Tuyamuyn
Hydro Complex and in the Amu Darya river flowing out from this reservoir, excluding Fe, all the examined metals showed lover
concentrations and values below the normative limits.
Conclusion The direct human consumption of the lower Amu Darya waters is strongly limited by salinity and by metal contamination. Although
the salinity of the return waters from the Bukhara drainage system results in above normal limits, no corresponding increases
were measured in the Amu Darya river downstream from the return water inflow at the time of the survey. As for the metal contamination
of the Amu Darya river, the survey revealed the presence of relevant sources of metal contamination downstream from Bukhara
external to the agricultural drainage system. This contamination resulted in reduced sedimentation processes taking place
in the limnetic zones of the Amu Darya river upstream to the dam forming the Tuyamuyn Hydro Complex.
Recommendation and Outlook To fully understand the longitudinal increase of Amu Darya salinity, an evaluation of the cumulative effects of the loads
from the main agricultural areas is required, also by using mass-balance models. As for the metals, an investigation should
be addressed to identify the anthropogenic sources of contaminations present in the lower Amu Darya region and the metal loads
should be diverted. 相似文献
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