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111.
The Irtysh river basin all the way from river spring in China across Kazakhstan as far as the Russian part of Siberia is among the most ecologically endangered and affected regions on our planet. The study provides a summary of the historical reasons for anthropological interventions in this area, which began with the construction of plants of the military—industrial complexes in the forties of the last century during World War II. These plants have a major share in extreme high concentrations of heavy metals in surface as well in groundwaters locally. The Semipalatinsk nuclear polygon plays a specific role as a source of contamination of local waters. The release of top secret data enabled us to gain knowledge about serious problems related to high radioactivity of groundwaters, which should spread uncontrollably through a system of secondary fissures activated by nuclear blasts. Another serious problem in this region is the quantitative aspect of contamination. Model simulations of water balance indicate that large industrial development in the spring area in China and continuously increasing water consumption in Kazakhstan may lead to desiccation of the lower stretch of this large river in Siberia during the summer months of 2030. 相似文献
112.
Subsurface dams to harvest rainwater— a case study of the Swarnamukhi River basin, Southern India 总被引:2,自引:0,他引:2
Declining water level trends and yields of wells, deterioration of groundwater quality and drying up of shallow wells are common in many parts of India. This is mainly attributed to the recurrence of drought years, over exploitation of groundwater, increase in the number of groundwater structures and explosion of population. In this subcontinent, the saving of water has to be done on the days it rains. India receives much of its rainfall in just 100 h in a year mostly during the monsoon period. If this water is not captured or stored, the rest of the year experiences a precarious situation manifest in water scarcity. The main objective behind the construction of subsurface dams in the Swarnamukhi River basin was to harvest the base flow infiltrating into sandy alluvium as waste to the sea and thereby to increase groundwater potential for meeting future water demands. An analysis of hydrographs of piezometers of four subsurface dams, monitored during October 2001–December 2002, reveals that there is an average rise of 1.44 m in post-monsoon and 1.80 m in the pre-monsoon period after the subsurface dams were constructed. Further, during the pre-monsoon month of June, much before construction of subsurface dams in October 2001, the water level was found fluctuating in the range of 3.1–10 m, in contrast to the fluctuation ranging from 0.4 to 3.1 m during the period following the construction of dams. Hence, the planning of rainwater harvesting structures entails thorough scientific investigations for identifying the most suitable locations for subsurface dams. 相似文献
113.
The Pedra Furada is a 12 m wide, 18 m high outcrop feature showing hundreds of ferruginised sandy tubes and looking in part like a giant organ. In this paper the origin of the tubes is explained on the basis of geochemical, petrographic and microscopic (optical and electronic) analytical data. The tubes are considered to represent vertical escape channels for overpressured water, exhibiting inward decreasing grain size due to water velocity gradients inside the escape channels. The ferruginisation is due to iron oxides associated with colloidal/clayey fine sediments and to goethite formed from solution. The overpressure of water may be due to seismically fluidised beds below the Pedra Furada outcrop or to artesian water ascent. In both cases, fault rupturing may have played a major role in the focussing of the ascending flow. 相似文献
114.
Over the last 10 years a great interest in spineless cactus pear was shown in the drier areas in terms of both fresh fruit and fodder production. However, there is a lack of knowledge on quantitative data on root dynamics of these plants needed to fully understand its potential under water limiting conditions. This study aimed at quantifying the effects of water stress on the growth of tap roots, side roots and rain roots of the species Opuntia ficus-indica (L.) Miller (cultivar Morado—green cladode) and O. robusta Wendl. (cultivar Monterey—blue cladode). One-year-old cladodes were planted in root boxes and pots (2002/2003 season) that were kept in the greenhouse at day/night temperatures of 25–30 °C/15–18 °C. Placing the cladodes flat on the soil, more areoles came in contact with the soil and therefore more roots developed in both species with an average of only 3.4% areole complexes not rooting. Each areole complex formed on average 3 roots. The highest daily tap root growth was 42 and 36 mm for O. ficus-indica and O. robusta, respectively. Tap root growth increased in the morning with water stress for both species but decreased in the afternoon. Side root growth increased with water stress, with that of O. robusta more per tap root than O. ficus-indica. O. robusta showed a finer root system than O. ficus-indica. The side roots grew as much as 8 and 5 mm per day for O. ficus-indica and O. robusta, respectively. Whitish rain roots developed on the established roots within the first hour after rewetting the soil and grew for only 3 days. Rain roots grew up to 7 and 5 mm within a day for O. ficus-indica and O. robusta, respectively. Considering all studied aspects of their roots systems, O. robusta appears to be better adapted to drought (less sensitive to water stress) than O. ficus-indica. 相似文献
115.
Under the assumptions of triangular cross section channel and uniform stable flow, an analytical solution of the minimum ecological in-stream flow requirement (MEIFR) is deduced. Based on the analytical solution, the uncertainty of the wetted perimeter method is analyzed by comparing the two techniques for the determination of the critical point on the relationship curve between wetted perimeter, P and discharge, Q. It is clearly shown that the results of MEIFR based on curvature technique (corresponding to the maximum curvature) and slope technique (slope being 1) are significantly different. On the P-Q curve, the slope of the critical point with the maximum curvature is 0.39 and the MEIFR varied prominently with the change of the slope threshold. This indicates that if a certain value of the slope threshold is not available for slope technique, curvature technique may be a better choice. By applying the analytical solution of MEIFR in the losing rivers of the Western Route South-to-North Water Transfer Project in China, the MEIFR value via curvature technique is 2.5%-23.7% of the multi-year average annual discharge, while that for slope technique is 11%-105.7%. General conclusions would rely on the more detailed research for all kinds of cross-sections. 相似文献
116.
C. Schnitchen D. J. Charman E. Magyari M. Braun I. Grigorszky B. Tóthmérész M. Molnár Zs. Szántó 《Journal of Paleolimnology》2006,36(1):1-17
Peatlands offer the potential for high resolution records of water balance over Holocene timescales, yet this potential is
under-exploited in many areas of the world. Within Europe, peatlands are mostly confined to areas north of 55° N, but several
areas of southern and eastern Europe contain small peatlands which may be suitable for palaeoclimatic reconstruction. In this
paper we test the potential of peatlands in the Carpathian region for deriving quantified estimates of water table changes
using testate amoebae analysis. A training set for palaeohydrological reconstruction from testate amoebae assemblages was
obtained by collecting surface samples from 13 peatlands, including 9 from Hungary and 4 from Transylvania (Romania). Using
a simple measure of mean annual water tables estimated from staining of PVC tape, we found that some peatlands were heavily
influenced by runoff and groundwater, and were therefore not suitable as modern analogues of ombrotrophic climatically sensitive
sites. The relationship between the testate amoebae assemblages in the modern samples and the environmental variables was
explored using CCA. The CCA biplot showed that the most important variables are depth to water table and moisture content,
confirming that hydrology is a key control on taxon distribution. pH was a secondary gradient. A transfer function for % moisture
and depth to water table was established and applied to fossil assemblages from a sequence from Fenyves-tető, Transylvania,
Romania. The reconstructed water table shows a number of variations which have parallels with other palaeoclimatic records
from Europe and the North Atlantic prominent phases of higher water tables are associated with the periods 8000–8300 cal BP,
3000–2500 cal BP and after 600 cal BP. We suggest that these were periods of particular intensification of westerly airflow
which affected eastern Europe as well as western and central Europe. 相似文献
117.
Christine S McCulloch 《Area》2006,38(1):24-33
Public participation in transparent decisionmaking has been proposed as a panacea for environmental protection. Bargaining theory suggests drawbacks to transparency such as hardening of attitudes and intransigence. Yet achievement of consensus on environmental values for integrated water resource management demands public involvement. Historical study of attempts to prevent reservoir construction in upland valleys designated for protection of nature suggests that 'closed-door' bargaining proved more effective for environmentalists than open, public debate. Records now open for analysis of disputes over Teesdale and Farndale, 1950–1970, allow comparisons to be made between behind-the-scenes deliberations and 'open-door' public discussion. The ambition of progressing from public participation to devolution of environmental decisionmaking and responsibility to the local scale demands more conceptualization of the process of decisionmaking on water resource development. 相似文献
118.
This paper contributes an empirical test of key themes of the literature on natural resource conflict. Survey and interview data from an ongoing project in Azerbaijan provide insights into an unexpected lack of conflict in Azerbaijan related to the environment, resources and energy despite the predictions of resource conflict literature. We contend that questions about public perceptions about the environment and other daily concerns are critical if we are to understand who is likely (or unlikely) to be involved in conflict and why. The data presented in this paper demonstrate that Azerbaijani citizens rank environmental and resource issues among their immediate concerns and their top concerns for the country. However, compared to other day-to-day concerns such as the Nagorno-Karabakh conflict and economic concerns, environment-related concerns do not appear to be sufficient to motivate widespread violent conflict or citizen dissent related to environmental or natural resource conditions. 相似文献
119.
Canada's environmental farm plans: transatlantic perspectives on agri-environmental schemes 总被引:2,自引:0,他引:2
GUY M ROBINSON 《The Geographical journal》2006,172(3):206-218
Evaluation of Ontario's Environmental Farm Plan (EFP) scheme, launched in 1993, provides an opportunity for comparisons with agri-environmental measures instituted in the European Union and other parts of North America. The EFP has a strong 'bottom-up' dimension in that it is farmers' organizations that have been central both to the scheme's instigation and to its ongoing management. This has affected the nature of the actions taken by individual farmers participating in the scheme. These actions are reviewed, especially in terms of the participants' attitudes towards stewardship of the land, environmental outcomes, cross-compliance measures, barriers to participation and the role of statutory regulation. Some contrasts are drawn with the greater 'top-down' controls exerted in several EU agri-environment schemes, with the latter's promotion of extensification and the changing role of farmers as 'producers of countryside' in a multi-functional agricultural system. The diffusion of EFP schemes throughout Canada is noted and is cited as confirming the maintenance of fundamentally different attitudes to the development of farm-based environmental actions compared with those adopted in the EU. 相似文献
120.
Decision-support systems for groundwater protection: innovative tools for resource management 总被引:1,自引:0,他引:1
Stefan Kollarits Gerhard Kuschnig Miran Veselic Ante Pavicic Corrado Soccorso Marina Aurighi 《Environmental Geology》2006,49(6):840-848
Governmental authorities are forced by law to make decisions within the framework of European, national and regional directives
in the fields of spatial planning, groundwater and environmental protection. These tasks can be supported by a decision-support
system, which integrates data from various sources and helps to make decision processes more effective and transparent. Basic
work for such a decision support system has been done in a transnational and interdisciplinary project (Interreg II C: KATER),
including metadata definition, metadata system, cartographic tools and GIS tools. The direct integration of these tools and
information in the decision process will be implemented in the next few years (project KATER II). 相似文献