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1.
The international conference on The African Experience with River Basin Development challenged participants to pursue a critical discussion of the record to date on approaches to river basin development and to propose appropriate strategies for the future. During the conference, special focus was given to the institutional requirements for planning, implementing and evaluating those strategies which benefit large numbers of people through increased production, enterprise development and employment generations in an environmentally sound fashion. It was noted that serious negative environmental and socio-economic effects have followed in the wake of African dam construction and the creation of large man-made lakes. The conference produced a short-list of general priorities for improving river basin development in Africa.  相似文献   

2.
The aim of this paper is, first, to examine the record to date for river basin development in tropical Africa; and second, to examine in more detail the role and performance of institutions in this record of African river basin development. The experience of institutions with river basin development are assessed against outcomes - namely, the extent to which the resources of Africa's river basins have actually been developed in recent years and the role that institutions have played in that development.  相似文献   

3.
From the outset of its efforts to promote the socio-economic development of river and lake basins in developing countries, UNDP took the position that in most cases the river basin was the appropriate geographical entity for development. However, the amount of technical Assistance required to evaluate the potentialities of a large river or lake basin is beyond the capabilities of any single donor of assistance. Similarly, the capital investment required to implement a basin development programme, ranging from US $ several hundred million to possibly US $ several thousand million, is usually beyond the capabilities of any single financial institution. On the basis of the experience gained in the development of the Mekong River and the Senegal River, UNDP advocates concerted and coordinated cooperation among donors interested in different aspects of one given large river or lake basin development, for which it coined the phrase 'multidonor approach'.  相似文献   

4.
The success of river and lake basin development and management is rooted in the knowledge of its resources, both physical and human. Within the framework of an integrated basin plan, each economic sector depends on the adequacy of such data for its individual development. The management and conservation of the basin itself in turn depends on knowing the requirements of those sectors and their probable impact on each other and on the status of the basin's resources, its ecology and environment. The development of African river basin resources is subject to various constraints, some for physical and climatic reasons, others tied to socio-cultural characteristics and the priorities of national economies. These are reflected in financial, manpower and institutional limitations, problems of finding technologies suited to specific local conditions and concern for human health. The scale and complexity of river basin development make it difficult to predict precise outcomes of planned proposals, but a progressive approach which links long-term activities with achievable, shorter term production projects offers prospects for ultimate success.  相似文献   

5.
6.
Phosphorus (P) in rivers in the Mississippi River basin (MRB) contributes to hypoxia in the Gulf of Mexico and impairs local water quality. We analyzed the spatial pattern of P in the MRB to determine the counties with the greatest January to June P riverine yields and the most critical factors related to this P loss. Using a database of P inputs and landscape characteristics from 1997 through 2006 for each county in the MRB, we created regression models relating riverine total P (TP), dissolved reactive P (DRP), and particulate P (PP) yields for watersheds within the MRB to these factors. Riverine yields of P were estimated from the average concentration of each form of P during January to June for the 10-yr period, multiplied by the average daily flow, and then summed for the 6-mo period. The fraction of land planted in crops, human consumption of P, and precipitation were found to best predict TP yields with a spatial error regression model ( = 0.48, = 101). Dissolved reactive P yields were predicted by fertilizer P inputs, human consumption of P, and precipitation in a multiple regression model ( = 0.42, = 73), whereas PP yields were explained by crop fraction, human consumption of P, and soil bulk density in a spatial error regression model ( = 0.49, = 61). Overall, the Upper Midwest's Cornbelt region and lower Mississippi basin had the counties with the greatest P yields. These results help to point out specific areas where agricultural conservation practices that reduce losses to streams and rivers and point source P removal might limit the intensity or spatial occurrence of Gulf of Mexico hypoxia and improve local water quality.  相似文献   

7.
Measurement of the primary production has been estimated over a study area of approximately 25 km2 of the North Koel River, in the Palamau District, in Bihar, India. A caustic chemical factory which is discharging effluent into the river is situated at Rehala, Palamau, on the bank of the North Koel. Huge amounts of mercury are released into the river. The physical and chemical characters of the caustic chemicals in the effluent have a significant influence on the primary production on the North Koel river. The gross production is compared with other fresh water habitats (riverine and other) in India. It is observed that the gross production value is the lowest (at 1.14 gc/m2/day) of any recorded riverine ecosystem in India.  相似文献   

8.
The value of cooperation in resolving international river basin disputes   总被引:3,自引:0,他引:3  
This paper reviews the phenomenon of international river basins, and concludes that the sharing of river basins between and among countries is the rule rather than the exception for the major river systems of the world. The growth of the nation state with rivers as agreed-upon boundaries, as cease-fire lines and as natural defensive lines has led to the carving up of most river basins around the world. More than 200 river basins, accounting for more than 50% of the land area of the Earth, are shared by two or more countries. When population densities were low, there was plenty of water for all and major conflicts were avoided. With the rapid population and economic growth experienced in the past few decades, conflicts over use of water are becoming more important. It is expected that in the near future such conflicts will become much more severe. The paper reviews the literature on attempts to analyse river basin conflicts and negotiate solutions. Some rudimentary game models are examined, and some tentative conclusions, based upon various game theory concepts of stability, are applied to the Ganges-Brahmaputra basin. The paper ends with suggestions on how to plan Pareto-Admissible outcomes for international basins.  相似文献   

9.
Water resource management in Kabul river basin, eastern Afghanistan   总被引:1,自引:0,他引:1  
Severe drinking water shortage affects all resident of the Kabul river basin. Two and a half decades of civil war in Afghanistan (it began in late 1978) have resulted in widespread environmental degradation and water resource development throughout the country. The war has already finished and, therefore, water resource management for supplying water is one of the most important tasks for Afghanistan’s government. The Kabul river basin which is the most populated area in the country is located in the eastern part of Afghanistan. This article deals with the water resource properties of the Kabul river basin and also water demand in the important cities of the basin, such as Kabul, the capital and the largest city in the country. Also a few suggestions for providing water for domestic and agriculture purposes in short term, medium time and long term have been discussed.  相似文献   

10.
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   

11.
The role of monitoring is changing due to the increasing awareness of complexity and uncertainty in environmental resources management. Monitoring systems are required to support critical reflection about the effectiveness of actions toward the achievement of management objectives. To this aim, monitoring should be based on a strong integrated and multi-scale approach. Monitoring costs could be prohibitive if the monitoring is only based on traditional scientific methods of measurements. To deal with these issues, the design of an innovative monitoring system should be based on the integration between different sources of knowledge and information. In this work the usability of local knowledge to support environmental monitoring is investigated. A multi-step participatory monitoring design process has been implemented aiming to design a program for soil salinity monitoring in the lower Amudarya river basin in Uzbekistan. Although there is an increasing awareness of the importance of stakeholders being involved in decision processes, the current socio-cultural and institutional context is not favourable to the participatory approach. The choice of method to be implemented in this work was influenced by such conditions. The analysis of the lessons learned from the experiences gained in this project revealed some important clues concerning the development of a locally-based monitoring program. These lessons can be subdivided according to three fundamental issues: the long term involvement of local community members in monitoring activities, the acceptance of locally-based monitoring systems by decision makers, and the reliability of monitoring information.  相似文献   

12.
Lohit is a major tributary of the river Brahmaputra in India and is famous for its rich and diverse fish fauna. The river has a difficult terrain, but has high hydropower potential. A large number of storage-based hydropower plants are envisaged on this river in the near-future. This study aims at presenting the existing diverse fish fauna in Lohit river basin. A total of 74 fish species are identified in this river basin and can be classified into seven orders, 20 families, and 52 genera. Further, it has been highlighted that there are seven species which have been categorized as endangered, 12 species are categorized to be vulnerable, three species have been categorized as data-deficient, and the remaining species are in the least concern category. It is expected that the construction of proposed storage-based power plants in this basin will affect the flow and storage characteristics, as well as the temperature of the water, which, in turn, will affect the rich fish fauna. This study emphasizes the need for preparing a comprehensive plan for the adoption of appropriate in situ conservation measures, as well as an awareness program, so as to save the rich and diverse fish fauna of Lohit river basin.  相似文献   

13.
Three innovations in water and soil conservancy technology in the Pearl River Delta of South China, i.e., dike building, land reclamation, and dike-pond systems, were examined from a historical perspective. They were found to best reflect local farmers' efforts to cope with the challenges of various water disasters and to build a harmonious relationship with the changed environment. These technologies were critical to the agricultural success and sustainability over the past 2000 years, and reflected local farmers' wisdom in balancing land use and environmental conservation. Imprudent use of a new agricultural technology could damage the environment, and could disturb the human-environment relationship, as evidenced by the more frequent flooding that followed inappropriate dike building and premature reclamation. It is suggested that as the urbanization and industrialization process in the delta region continues, the kind of thinking that made the water and soil conservancy sustainable needs to be incorporated into the design of similar technologies for water use and river basin management today.  相似文献   

14.
Collaboration has rapidly become the dominant paradigm in natural resource management, but there are many dilemmas about how it is applied effectively. In southwest Oregon, agencies, watershed councils and other stakeholders are developing a river basin approach to assess ecological health and set priorities for restoration. An analysis of this process reveals considerable progress in this innovative effort and it reveals several implications for collaboration at a regional scale, including: tensions between technical complexity and open participation, difficulties with information exchange for joint management, the relationships between technical issues and policy issues, the role of regional policy in supporting collaborative efforts, and the importance of institutional arrangements.  相似文献   

15.
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   

16.
Summary It has been established that the electrodes of the dialyser in a chloro-alkali plant in Eastern India release mercury beyond the permissible limits into the River Koel. Mercury in elemental form, as well as certain organo-mercury compounds, including methyl mercury, have been detected at a distance of 25 km from the discharge point. Even at a distance of 5–10 km, the mercury content of the sediment may be as high as 0.6–3.2 mg kg–1 above the value of sediment upstream of the plant. This sediment itself is contaminated, probably by battery and paint factories, etc., still further upstream. Thus, the chloro-alkali factory has contributed 60–320 times above the permissible limit (0.01 mg kg–1) of mercury release, at a distance of 5–10 km from the point of release. Furthermore, various phytoplankton and zooplankton have been contaminated, leading to very high mercury contents in certain fish. This food chain, therefore, threatens man himself.Dr Sajalendu Nanda is currently a Research Associate at Bangur Institute of Neurology in Calcutta. He possesses an MSc in Environmental Biology and a PhD in Ecology. His address for correspondence is c/o Dr P.K. Tapaswi, Professor-in-Charge at the Biological Sciences Division of the Indian Statistical Institute.  相似文献   

17.
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   

18.
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   

19.
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   

20.
Traditionally, the multiple linear regression technique has been one of the most widely used models in simulating hydrological time series. However, when the nonlinear phenomenon is significant, the multiple linear will fail to develop an appropriate predictive model. Recently, neuro-fuzzy systems have gained much popularity for calibrating the nonlinear relationships. This study evaluated the potential of a neuro-fuzzy system as an alternative to the traditional statistical regression technique for the purpose of predicting flow from a local source in a river basin. The effectiveness of the proposed identification technique was demonstrated through a simulation study of the river flow time series of the Citarum River in Indonesia. Furthermore, in order to provide the uncertainty associated with the estimation of river flow, a Monte Carlo simulation was performed. As a comparison, a multiple linear regression analysis that was being used by the Citarum River Authority was also examined using various statistical indices. The simulation results using 95% confidence intervals indicated that the neuro-fuzzy model consistently underestimated the magnitude of high flow while the low and medium flow magnitudes were estimated closer to the observed data. The comparison of the prediction accuracy of the neuro-fuzzy and linear regression methods indicated that the neuro-fuzzy approach was more accurate in predicting river flow dynamics. The neuro-fuzzy model was able to improve the root mean square error (RMSE) and mean absolute percentage error (MAPE) values of the multiple linear regression forecasts by about 13.52% and 10.73%, respectively. Considering its simplicity and efficiency, the neuro-fuzzy model is recommended as an alternative tool for modeling of flow dynamics in the study area.  相似文献   

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