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1.
Assessment of habitat quality with relation to fish assemblages in an impacted river of the Ganges basin, northern India 总被引:1,自引:0,他引:1
In this work, we examined water-quality assessment in relation to fish assemblage of Gomti River, a large tributary of the
Ganges River basin in northern India. Principal component analysis was performed for 18 environmental variables which produced
three axes that cumulatively explained 60.23% of the environmental variation in sites. Fifteen variables (fine substrate fine
gravel, coarse gravel, cobble, sand substrate water flow, conductivity, TDS, total hardness, temperature, dissolved oxygen,
pH, and overhanging vegetation) had high loadings on at least one of the principal component axes interpreted. The canonical
correspondence analysis was used to establish the relationship between important fish species and environmental variables.
Species were distributed within four groups with respect to the significant habitat characteristics. The Pearson correlation
coefficient was calculated between the water-quality parameters. We concluded that the level of species richness is mostly
dependent on abiotic factors like temperature, dissolved oxygen, TDS, conductivity, depth, pH, and water current in the Gomti
River, of the Ganges basin. 相似文献
2.
Vegetation and carbon sequestration and their relation to water resources in an inland river basin of Northwest China 总被引:1,自引:0,他引:1
In the Heihe River Basin in the arid inland area of northwest China, the distribution of water resources in vegetation landscape zones controls the ecosystems. The carbon sequestration capacity of vegetation is analyzed in relation to water resources and vegetation growing conditions. During the last 20 years, the vegetation ecosystems have degenerated in the Heihe River Basin. Simulation using the C-FIX model indicates that, at present, the total amount of NPP of vegetation accounts for about 18.16 TgC, and the average value is 106 gC/m(2)/yr over the whole basin. NPP has generally the highest value in the upperstream mountain area, middlestream artificial oases area, downstream river bank area, alluvial fan and the terminal lake depression where vegetation grows relatively well. The lowest value is found in the vast downstream desert and Gobi area. Protection of vegetation ecosystems and enhancement of carbon sequestration require such inland river basins as the Heihe River Basin to be brought under management in a comprehensive way, taking water as a key, to carry out a rational and efficient allocation and utilization of water resources. 相似文献
3.
4.
Kronvang B Audet J Baattrup-Pedersen A Jensen HS Larsen SE 《Journal of environmental quality》2012,41(2):304-313
Phosphorus loss from bank erosion was studied in the catchment of River Odense, a lowland Danish river basin, with the aim of testing the hypothesis of whether stream banks act as major diffuse phosphorus (P) sources at catchment scale. Furthermore, the study aimed at analyzing the impact of different factors influencing bank erosion and P loss such as stream order, anthropogenic disturbances, width of uncultivated buffer strips, and the vegetation of buffer strips. A random stratified procedure in geographical information system (GIS) was used to select two replicate stream reaches covering different stream orders, channelized vs. naturally meandering channels, width of uncultivated buffer strips (≤ 2 m and ≥ 10 m), and buffer strips with different vegetation types. Thirty-six 100-m stream reaches with 180 bank plots and a total of 3000 erosion pins were established in autumn 2006, and readings were conducted during a 3-yr period (2006-2009). The results show that neither stream size nor stream disturbance measured as channelization of channel or the width of uncultivated buffer strip had any significant ( < 0.05) influence on bank erosion and P losses during each of the 3 yr studied. In buffer strips with natural trees bank erosion was significantly ( < 0.05) lower than in buffer strips dominated by grass and herbs. Gross and net P input from bank erosion amounted to 13.8 to 16.5 and 2.4 to 6.3 t P, respectively, in the River Odense catchment during the three study years. The net P input from bank erosion equaled 17 to 29% of the annual total P export and 21 to 62% of the annual export of P from diffuse sources from the River Odense catchment. Most of the exported total P was found to be bioavailable (71.7%) based on a P speciation of monthly suspended sediment samples collected at the outlet of the river basin. The results found in this study have a great importance for managers working with P mitigation and modeling at catchment scale. 相似文献
5.
The river Rhine has been in humanity's use for many centuries for a variety of activities. However, in our time, considerable changes in the course and the natural conditions of the river and the increasing use of the river for the discharge of wastewater has caused serious floods and major ecological problems. Since 1950, the International Commission for the Protection of the Rhine (ICPR) acts as the coordination point between the states bordering the Rhine for the development of programmes for river protection. The Sandoz disaster in 1986 was a turning point in the approach of the ICPR and the starting point for the present strategy of integrated riverbasin management. Recent developments have indicated the success of the current approach. 相似文献
6.
Terence R Lee 《Natural resources forum》1995,19(3):243-248
Traditionally, in most countries of Latin America, the management of water and water based services has been highly centralized in the public sector. Recently, as the role of government has been reconsidered, many services have been transferred to lower levels of government or to the private sector. At the same time, the emphasis given to water projects as basic development tools has given way to the environmental significance of good water management. Consequently, the approach to water resources management has been modified and space created for the adoption of some of the basic precepts enunciated in the Mar del Plata Action Plan and Agenda 21. In particular, in various countries consideration is being given to water management through river basin institutions . 相似文献
7.
The quantities of water are not distributed uniformly in space and time. Greece compared to some other Mediterranean countries
is found in advantageous position regarding the availability of water resources. However, there are regions with great in
quantity water reserves and others with intense deficiencies. The management of water resources in Greece is concentrated
in the systematic spatiotemporal monitoring and forecast of two basic multidimensional parameters, the availability of water
resources and the water demand, as well as, in the implementation of necessary measures for the satisfaction of needs, regarding
the fields of economy and environment. This work describes and analyses the existing status of water resources in Greece,
as well as, the framework of applied policy. Furthermore, measures and actions for the management of water resources are proposed. 相似文献
8.
M. Monirul Qader Mirza 《Environmental management》1998,22(5):711-722
/ The Ganges River supplies water to the southwest region of Bangladesh mainly through one of its distributaries-the Gorai River. India commissioned a barrage on the Ganges River at Farakka in April 1975 to divert water and make the Bhagirathi-Hooghly River navigable. The diversion has reduced the dry season discharge of the Ganges and Gorai rivers in Bangladesh. Statistical analyses indicate that the changes in the dry season discharge of these rivers are significant. Reduced discharge in the Gorai River has induced accelerated sedimentation and increased salinity in the southwest region of Bangladesh. Empirical analyses demonstrate the relationship between discharge in the Gorai River and salinity. Analyses also determine the requirement of flow for the Ganges and Gorai rivers to keep salinity at threshold limits. Increased salinity has caused negative effects on agriculture, forestry, industry, and drinking water in the southwest region of Bangladesh.KEY WORDS: Bangladesh; Ganges River; Gorai River; Farakka diversion; Salinity 相似文献
9.
Sources of water pollution and evolution of water quality in the Wuwei basin of Shiyang river, Northwest China 总被引:3,自引:0,他引:3
Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced. 相似文献
10.
Source water protection planning (SWPP) is an approach to prevent contamination of ground and surface water in watersheds where these resources may be abstracted for drinking or used for recreation. For SWPP the hazards within a watershed that could contribute to water contamination are identified together with the pathways that link them to the water resource. In rural areas, farms are significant potential sources of pathogens. A risk-based index can be used to support the assessment of the potential for contamination following guidelines on safety and operational efficacy of processes and practices developed as beneficial approaches to agricultural land management. Evaluation of the health risk for a target population requires knowledge of the strength of the hazard with respect to the pathogen load (massxconcentration). Manure handling and on-site wastewater treatment systems form the most important hazards, and both can comprise confined and unconfined source elements. There is also a need to understand the modification of pathogen numbers (attenuation) together with characteristics of the established pathways (surface or subsurface), which allow the movement of the contaminant species from a source to a receptor (water source). Many practices for manure management have not been fully evaluated for their impact on pathogen survival and transport in the environment. A key component is the identification of potential pathways of contaminant transport. This requires the development of a suitable digital elevation model of the watershed for surface movement and information on local groundwater aquifer systems for subsurface flows. Both require detailed soils and geological information. The pathways to surface and groundwater resources can then be identified. Details of land management, farm management practices (including animal and manure management) and agronomic practices have to be obtained, possibly from questionnaires completed by each producer within the watershed. To confirm that potential pathways are active requires some microbial source tracking. One possibility is to identify the molecular types of Escherichia coli present in each hazard on a farm. An essential part of any such index is the identification of mitigation strategies and practices that can reduce the magnitude of the hazard or block open pathways. 相似文献
11.
Arsenic levels were determined in 62 stations utilized as drinking and potable water resources by local community for Turkey's Aksaray Province (4589 km(2); 980 m above sea level). The samplings were implemented every two months for 1 year. The arsenic values were found to be ranging between 10 and 50 μg/L in 22 points and were found to be >50 μg/L in 5 stations, according to the mean value of the 6 samples. WHO and the Turkish Standards have permitted an arsenic concentration of 10 μg/L in drinking waters. The multivariate statistical technique, cluster analysis (CA), followed by principal component analysis (PCA) were applied to the data on 17 water quality parameters in 47 stations that are used for drinking and other domestic resources. Two significant sampling locations were detected based on the similarity of their water quality. The chemical correlations were observed in the two sub-sampling locations by Principal Component Analysis. 相似文献
12.
Planning for change and sustainability in water development in Lao PDR and the Mekong River basin 总被引:1,自引:0,他引:1
Jeffrey W Jacobs 《Natural resources forum》1996,20(3):175-187
With its recent opening to the global market economy, the natural resources of the Lao People's Democratic Republic (Lao PDR, referred to in this paper as Laos) – especially its water resources–have attracted external interest and investment. The overall level of water development is low. While even modest development would help Laos meet some of its urgent needs, past experience in Southeast Asia and other tropical regions suggests that fast-paced water development may damage the natural resource base. This article examines some efforts in water development from Southeast Asia and other regions and their relevance to water policy formulation in Laos. Future social and environmental changes in Laos are inevitable, but the nature and direction of these changes are uncertain. It thus makes sense to design policies that are flexible and can be adjusted to, and even take advantage of, a changing social and environmental context. Smaller-scale, deliberately-paced projects which merge local knowledge and external expertise fulfil the requirements of flexibility and adjustability, and are also appropriate for other important reasons: they do not require massive inputs of funding, and they do not initiate large-scale environmental and socio-economic changes. Current knowledge of the complex ecological and social systems in Laos is only sketchy. A slower-paced development will allow developers the necessary time to learn more about these important aspects. 相似文献
13.
David Pearce 《Resources Policy》1987,13(4)
New models of sustainable development stress the importance of the efficient management of resources, including labour, capital equipment and natural resources. Overuse of the resource base today will lead to shortages tomorrow; yet it can be a difficult task persuading politicians and planners in developing countries of the importance of resource management. This paper suggests methodologies for doing so and argues the urgency of the task. 相似文献
14.
Predicting the economic and demographic impacts of resource development on regional areas is difficult to assess because of limited availability of analysis, difficulties of predicting where workforce are likely to be based, and different impacts on communities because of variations in size and economic structures. In this study modelling has been employed to identify future employment and demographic impacts of future resource developments on communities in the Surat Basin in southern Queensland, Australia. The analysis summarises potential employment increases over multiple projects and uses multipliers from Input–Output models to assess likely impacts by local government area when future workforce might commute to or live locally in the region. The results demonstrate that recent moves to commuting workforces limit the economic impacts on local and regional communities in complex ways. 相似文献
15.
Williams MR Filoso S Martinelli LA Lara LB Camargo PB 《Journal of environmental quality》2001,30(3):967-981
Annual precipitation and river water volumes and chemistry were measured from 1995 to 1998 in a mesoscale agricultural area of southeast Brazil. Precipitation was mildly acidic and solute concentrations were higher in the west than in the east of the basin. Combustion products from biomass burning, automobile exhaust, and industry typically accumulate in the atmosphere from March until October and are responsible for seasonal differences observed in precipitation chemistry. In river waters, the volume-weighted mean (VWM) concentrations of major solutes at 10 sites across the basin were generally lower at upriver than at downriver sampling sites for most solutes. Mass balances for major solutes indicate that, as a regional entity, the Piracicaba River basin was a net sink of H+, PO4(3-), and NH4+, and a net source of other solutes. The main stem of the Piracicaba River had a general increase in solute concentrations from upriver to downriver sampling sites. In contrast, NO3- and NH4+ concentrations increased in the mid-reach sampling sites and decreased due to immobilization or utilization in the mid-reach reservoir, and there was denitrification immediately downriver of this reservoir. Compared with tributaries of the Chesapeake Bay estuary, the Piracicaba River is affected more by point-source inputs of raw sewage and industrial wastes than nonpoint agricultural runoff high in N and P. Inputs of N and C are responsible for a degradation of water quality at downriver sampling sites of the Piracicaba River drainage, and water quality could be considerably improved by augmenting sewage treatment. 相似文献
16.
In animal production systems (poultry, beef, and swine), current production, storage, and disposal techniques present a challenge to manage wastes to minimize the emissions of trace gases within relatively small geographical areas. Physical and chemical parameters were measured on primary and secondary lagoons on three different swine farming systems, three replicates each, in the Central Great Basin of the United States to determine ammonia (NH3) emissions. Nutrient concentrations, lagoon water temperature, and micrometeorological data from these measurements were used with a published process model to calculate emissions. Annual cycling of emissions was determined in relation to climatic factors and wind speed was found the predominating factor when the lagoon temperatures were above about 3 degrees C. Total NH3 emissions increased in the order of smallest to largest: nursery, sow, and finisher farms. However, emissions on an animal basis increased from nursery animals being lowest to sow animals being highest. When emissions were compared to the amount of nitrogen (N) fed to the animals, NH3 emissions from sows were lowest with emissions from finisher animals highest. Ammonia emissions were compared to similar farm production systems in the humid East of the United States and found to be similar for finisher animals but had much lower emissions than comparable humid East sow production. Published estimates of NH3 emissions from lagoons ranged from 36 to 70% of feed input (no error range) compared to our emissions determined from a process model of 9.8% with an estimated range of +/-4%. 相似文献
17.
Existing and projected water shortages and related factors have helped focus attention on the need for water reuse. With recent technological advances in wastewater treatment, it is now possible to produce reclaimed water of any quality. Thus, the use of reclaimed water will depend on the reuse opportunities and the cost of the required infrastructure. Historically, centralized wastewater treatment facilities have served the needs of organized societies since the mid 1800s. However, as there are limited options for expansion of most existing centralized facilities, the use of satellite and decentralized wastewater management systems offers significant advantages including being close both to the source of wastewater generation and to potential water reuse applications. The comparative advantages of satellite and decentralized wastewater management systems for a number of water reuse applications are presented and discussed in this paper. Selected case studies are presented to demonstrate the utility of satellite and decentralized wastewater management. Specific issues associated with the application of such systems in existing and in new developments are examined and discussed. 相似文献
18.
Pyar Ali Memon 《Environmental management》1989,13(5):553-562
The Clutha is the largest river in New Zealand. The last two decades have witnessed major conflicts centered on the utilization of the water resources of the upper Clutha river. These conflicts have by no means been finally resolved. The focus of this article is on institutional arrangements for water resource management on the Clutha, with particular reference to the decision-making processes that have culminated in the building of the high dam. It critically evaluates recent experiences and comments on future prospects for resolving resource use conflicts rationally through planning for multiple utilization in a climate of market led policies of the present government.The study demonstrates the inevitable conflicts that can arise within a public bureaucracy that combines dual responsibilities for policy making and operational functions. Hitherto, central government has been able to manipulate the water resource allocation process to its advantage because of a lack of clear separation between its two roles as a policy maker and developer. The conflicts that have manifested themselves during the last two decades over the Clutha should be seen as part of a wider public debate during the last two decades concerning resource utilization in New Zealand. The Clutha controversy was preceded by comparable concerns over the rising of the level of Lake Manapouri during the 1960s and has been followed by the debate over the think big resource development projects during the 1980s.The election of the fourth Labour government in 1983 has heralded a political and economic policy shift in New Zealand towards minimizing the role of public intervention in resource allocation and major structural reforms in the relative roles of central and regional government in resource management. The significance of these changes pose important implications for the future management of the Clutha. 相似文献
19.
Pesticides in surface water,sediment, and rainfall of the northeastern Pantanal basin,Brazil 总被引:2,自引:0,他引:2
Laabs V Amelung W Pinto AA Wantzen M da Silva CJ Zech W 《Journal of environmental quality》2002,31(5):1636-1648
Within the last 25 years an intensive agriculture has developed in the highland regions of Mato Grosso state (Brazil), which involves frequent pesticide use in highly mechanized cash-crop cultures. To provide information on pesticide distribution and dynamics in the northeastern Pantanal basin (located in southern Mato Grosso), we monitored 29 pesticides and 3 metabolites in surface water, sediment, and rainwater of the study area during the main application season. In environmental samples, 19 pesticides and 3 metabolites were detected in measurable quantities, resulting in at least one pesticide detection in 68% of surface water samples (n = 139), 62% of sediment samples (n = 26), and 87% of rainwater samples (n = 91). Surface water samples were most frequently contaminated by endosulfan compounds (alpha-, beta-, -sulfate), ametryn, metolachlor, and metribuzin, although in low (< 0.1 microgram L-1) concentrations. Sediment samples exhibited concentrations up to 4.5 micrograms kg-1 of p,p'-DDT, p,p'-DDE, endosulfan-sulfate, beta-endosulfan, and ametryn. In contrast, rainwater was polluted with substantial amounts of endosulfan, alachlor, metolachlor, trifluralin, monocrotofos, and profenofos (maximum concentrations = 0.3 to 2.3 micrograms L-1) in the highlands. Lowland rainwater samples taken 75 km from the next application area contained 5- to 10-fold lower mean pesticide concentration than in the highlands. Cumulative deposition rates of the pesticide sum within the study period ranged from 423 micrograms m-2 in the highlands to 14 micrograms m-2 in the lowlands. The atmospheric input of pesticides to ecosystems seemed to be of higher relevance in the tropical study area than known from temperate regions. 相似文献
20.
Governance of water supply systems in the Palestinian Territories: A data envelopment analysis approach to the management of water resources 总被引:2,自引:0,他引:2
This study demonstrates that data envelopment analysis (DEA) can be a useful tool to assess the relative efficiencies of water supply systems and to establish benchmarks with which to measure progress in the management of water resources. Frontier efficiency models measure the efficiency of water use in the Palestinian Territories (West Bank and the Gaza Strip). At the municipality level, sufficient data for the years 1999-2002 were available to estimate efficiency and stability scores. The Gaza Strip efficiency scores were considerably lower than those of the West Bank. Water losses were the major source of the inefficiency as indicated by the large slacks of this input. The relative sizes of the municipalities affect efficiency scores little. Palestinian policy makers should focus on rebuilding the infrastructure of the water networks, beginning with the most DEA inefficient municipalities in order to minimize water losses. 相似文献