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1.
Edna Waithaka Edwine Yongo Nicholas Outa Eunice Mutethya 《Lakes & Reservoirs: Research and Management》2020,25(2):244-249
The Nile tilapia (Oreochromis niloticus) was introduced into Lake Naivasha to provide exploitable fisheries, being one of the commercially important fish providing livelihoods to communities around the lake. Its stocks in the lake have been declining, however, because of intense fishing, ecological changes and effects of other exotic species. The present study was undertaken to investigate the population and biological parameters of Oreochromis niloticus. Fish samples (1,021) were caught monthly from January to December 2017, collecting a total of 1,021 O. niloticus, with an overall sex ratio of 2.21:1.0 (male: female). The length of the fish ranged from 9.0 to 40.0 cmTL and weighed between 20 and 1,220 g. The mean length and weight for all fish was 22.6 cm and 272.6 g. The slope b of length–weight relationship was 2.86 for all fish, indicating negative allometry. The mean condition factors were 0.99, 1.04 and 1.01 for male, female and all fish, respectively. The length at first maturity (Lm50) was estimated to be 28.0 cmTL for all sexes, indicating the fish matures at smaller sizes. The length at first capture (Lc50) was calculated to be 19.38 cm, a value much lower than its Lm50, reflecting the capture of juvenile fish. The asymptotic length (L∞) was 42 cm, the growth coefficient (K) was 0.21/year, and the growth performance index (Ф) was 2.57. The natural (M), fishing (F) and total mortality (Z) coefficients were estimated to be 0.55, 0.26 and 0.80/year, respectively. The optimum sustainable yield (E0.5), maximum sustainable yield (Emax) and maximum economic yield (E0.1) indices of 0.23, 0.35 and 0.26, respectively, imply an optimal exploitation of O. niloticus. The results of the present study provided some important insights into the biology and management needs of the O. niloticus fishery in Lake Naivasha, as well as revealing a gap for further research on its reproductive biology. 相似文献
2.
Edwine Yongo Simon Agembe Nicholas Outa Monica Owili 《Lakes & Reservoirs: Research and Management》2018,23(1):17-23
This study investigated the growth, mortality and recruitment of Lates niloticus in Lake Victoria basis on length–frequency data collected during the period 2014‐2015. The asymptotic length (L ∞ ) had a value of 124 cm TL , growth curvature (K ) of 0.22 year?1, total mortality (Z ) of 0.96 year?1, a natural mortality (M ) of 0.42 year?1, a fishing mortality (F ) of 0.54 year?1, an exploitation rate (E ) of 0.57 and a growth performance index () of 3.53. Logistic selection model showed that 50% of fish of 46.09 cm TL encountering the gear are retained. There were two peak recruitment periods, a minor one in March and a major one in July, accounting for 12.04% and 22.04%, respectively, of the total fish catch. The Beverton and Holt's relative yield‐per‐recruit model indicated the indices for sustainable yields are 0.32 for optimum sustainable yield (E 0.5), 0.60 for maximum sustainable yield (E max) and 0.51 for economic yield (E 0.1). Compared to previous findings, there is a great decline in the sizes of Nile perch stocks in Lake Victoria. Thus, managing the fishery requires strict adherence to the slot size of 50–85 cm TL , and restrictions on illegal gear and methods, by the devolved governments through monitoring, control and surveillance in liaison with the Beach Management Units (BMU s). 相似文献
3.
Natugonza Vianny Ogutu‐Ohwayo Richard Efitre Jackson Muyodi Fredrick Mbabazi Dismas Olokotum Mark Musinguzi Laban Naigaga Shamim Namboowa Sharon 《Lakes & Reservoirs: Research and Management》2015,20(2):101-119
Changes in the catches of Nile tilapia, Oreochromis niloticus (Linnaeus, 1758), in Lake Wamala (Uganda) have been observed since its introduction. The factors contributing to these changes, however, are not well understood. This study examined changes in species composition, size structure, size at first maturity, length–weight relationship and condition factor of Nile tilapia in Lake Wamala, in relation to changes in temperature, rainfall and lake depth, to provide a better understanding of the possible role of changing climatic conditions. There was an increase in the minimum, maximum and average temperatures since 1980, but only the minimum (0.021 °C year?1) and average temperatures (0.018 °C year?1) exhibited a significant trend (P < 0.05). Rainfall increased by 8.25 mm year?1 since 1950 and accounted for 79.5% of the water input into the lake during the period 2011–2013, while evaporation accounted for 86.2% of the water loss from the lake. The lake depth was above 4 m during the years when the rainfall exceeded the average of 1180 mm, except after 2000. The contribution of Nile tilapia to total fish catch and catch per unit effort (CPUE) increased with rainfall and lake depth up to the year 2000, after which they decreased, despite an increased rainfall level. The lake depth was positively correlated with the average total length and length at 50% maturity (r = 0.991 and 0.726, respectively), while the slopes of the length–weight relationships differed significantly between high and low lake depths [t(6) = 3.225, P < 0.05]. Nile tilapia shifted from an algal‐dominated diet during the wet season to include more insects during the dry season. The results of this study indicate Nile tilapia in Lake Wamala displays a typical r‐selected reproductive strategy, by growing to a small size, maturing faster and feeding on different food types, in order to survive high mortality rates under unfavourable conditions attributable to higher temperatures, low rainfall and low lake water levels. 相似文献
4.
P. K. Ofori-Danson 《Lakes & Reservoirs: Research and Management》2005,10(3):191-197
An assessment has been made of the stock conditions of five major component fishery species (Chrysichthys nigrodigitatus, Chrysichthys auratus, Hemisynodontis membranaceus, Oreochromis niloticus and Schilbe intermedius) exploited with illegal purse‐seine (winch‐net) gear in the Yeji sector of Lake Volta, Ghana. Chrysichthys nigrodigitatus was clearly found to be overexploited, but the others were being exploited near to, or under, optimum harvest levels. All five species were harvested at an inappropriate age‐at‐first‐capture of ≈ 6 months, suggesting overfishing of young fishes. Consequently, the computed Lm:L∞ ratios were > 0.64. For most fish species, such a ratio implies their exploitation when at early maturity and at very small sizes. The estimated range of mesh sizes in the cod‐ends was far lower (5–8 mm) than the legal mesh size of 25 mm, calling for urgent enforcement of rules and regulations. Single‐species yield‐per‐recruit analyses indicated that yields could be improved by the reduction in the current fishing effort. As the fishery of the lake is not segmented to allow fish to be taken by the illegal small‐mesh purse seines, studies on the interactions between the different fishery sectors need to be undertaken, alongside the proposed ban of the gear as enshrined in the Fisheries Law of Ghana. 相似文献
5.
Daniel Nsoh Akongyuure Regina Edziyie 《Lakes & Reservoirs: Research and Management》2020,25(2):157-166
Five major commercial fish species, comprising Sarotherodon galilaeus, Oreochromis niloticus, Coptodon zillii, Clarias gariepinus and Auchenoglanis occidentalis of the Tono Reservoir fishery, were studied from January, 2015 to December, 2016 using length‐based models to establish the state of the stocks. Routines in the FAO‐ICLARM Stock Assessment Tools II (FISAT II) were used to determine the growth and mortality parameters, exploitation rates (E) and recruitment patterns of the length–frequency data generated from commercial fish landings and experimental catches. The growth coefficients (K) of the five fish species ranged 0.48–4.89 per year; asymptotic lengths (L∞) ranged from 18.38 to 76.16 cm; and hypothetical ages (t0) ranged between 0.03 and 0.28 years. All five fish species were exploited above the optimal exploitation rate (Eopt = 0.5), indicating overfishing of the species. There was a year‐round recruitment, with major and minor peaks corresponding with the major and minor spawning seasons. Fishing gear regulation and community‐based co‐management system were some management options recommended to enhance sustainable exploitation and management of the fishery. 相似文献
6.
Saima Andrabi;Yahya Bakhtiyar;Mohammad Yasir Arafat;Abrar Ahmad Bhat;Muni Parveen; 《Lakes & Reservoirs: Research and Management》2024,29(1):e12458
The present work was carried out to study the demographic aspects of Cyprinus carpio, an invasive species and an ecological pest capable of universal existence. Data on length–frequency was obtained from the two varieties of C. carpio from the deepest freshwater lake of India, Manasbal Lake, over a time period of 1 year (March 2019–February 2020) and analysed using the FiSAT-II software. The mean total length was reported to be 18.58 cm for C. carpio var. communis and 19.18 cm for C. carpio var. specularis, with the dominant length groups being 20–21 and 19–20 cm, respectively. The length–weight relationship parameters yielded the equation logTW = (2.56) logTL − 1.30, r = 0.94, for C. carpio var. communis, with a condition factor (K) value of 1.42 ± 0.25, and logTW = (2.53) logTL − 1.26, r = 0.93 for C. carpio var. specularis, with a condition factor (K) value of 1.38 ± 0.20. Different parameters obtained from the von Bertalanffy growth equation included L∞ = 38.85 cm; K = 0.170/year; ø′ = 2.409 and t0 = −0.93 for C. carpio var. communis, and L∞ = 30.45 cm; K = 0.210/year; ø′ = 2.289 and t0 = −0.80 for C. carpio var. specularis. The mortality parameters, including total, natural and fishing mortality, were also estimated for C. carpio var. communis to be Z = 0.08, M = 0.40 and F = −0.32, and for C. carpio var. specularis, to be Z = 0.22, M = 0.49 and F = −0.27, respectively. The exploitation rate (E) estimated for both varieties revealed its very less exploitation, suggesting more efficient methods to explore Manasbal Lake to its full capacity and to determine proper measures needed to be taken to conserve the native fauna. 相似文献
7.
Edwine Yongo Julius Manyala Simon Agembe 《Lakes & Reservoirs: Research and Management》2018,23(3):244-249
This study investigated the growth, mortality and recruitment of Rastrineobola argentea in Lake Victoria on the basis of length–frequency data collected during the period 2014–2015. The asymptotic length (L ∞ ) had a mean (±SE ) value of 53.50 ± 0.50 mm SL , growth curvature (K ) of 0.81 ± 0.06 year?1, total mortality (Z ) of 2.96 ± 0.12 year?1, a natural mortality (M ) of 1.23 ± 0.06 year?1, a fishing mortality (F ) of 1.74 ± 0.07 year?1, an exploitation rate (E ) of 0.59 ± 0.01, a growth performance index (?′ ) of 3.36 ± 0.02 and a length at 50% capture (L 50) of 28.25 ± 0.43 mm SL . The fish exhibited a peak breeding during the months of May and August. The Beverton and Holt relative yield‐per‐recruit model indicated mean (±SE ) indices as 0.37 ± 0.01 for optimum sustainable yield (E 0.5), 0.76 ± 0.01 for maximum sustainable yield (E max) and 0.66 ± 0.01 for economic yield (E 0.1). Compared with previous studies, there is a great decline in the sizes of R. argentea stocks in Lake Victoria. Thus, management measures should include restriction on illegal seine nets <10 mm mesh size and re‐enforcement of a fishing ban or a closed season. 相似文献
8.
Workiyie Worie Assefa Ayalew Wondie Belachew Getnet Enyew 《Lakes & Reservoirs: Research and Management》2019,24(4):344-353
Oreochromis niloticus is the dominant commercial fish in the Lake Tana region. However, its fishery is progressively declining over time. Little or no updated information exists on the population dynamics and exploitation patterns of the species, which is crucial to guide its sustainable management. Accordingly, the purpose of the present study was to generate essential biological parameters on the growth, mortality and stock status of O. niloticus, using length‐frequency data collected monthly from the commercial fish catches of 1 year (2014–2015). The total mortality coefficient (Z) was derived from the length‐converted catch curve. Biological reference points were predicted from relative yield‐ and biomass‐per‐recruit analyses. The estimated values of the von Bertalanffy growth parameters were L∞ = 44.1 cm, K = 0.44/year, and t0 = ?0.34/year, and the growth performance index (Φ′) was 2.93. The total mortality (Z), natural (M) and fishing mortality (F) rates were 2.37, 0.98 and 1.39 per year, respectively. The current fishery exploitation rate of 0.59 exceeds the estimated biological reference points of Emax (0.52), confirming the stock of O. niloticus in the lake is being overexploited above optimum levels. Size indicators of the catches further illustrate 31% of the landed fish are harvested before reaching sexual maturity, with mega‐spawners comprising only 15%. This indicates the stock is suffering from both growth and recruitment overfishing. The logistic selection model indicated 50% of the fish vulnerable to capture was at 18.14 cm TL. The fish exhibited a year‐round recruitment pattern, with a major peak during May and June. Sustainably managing the fishery, therefore, requires increasing the fish size at first capture (Lc) towards Lopt. 相似文献
9.
Eunice Mutethya Edwine Yongo Cishahayo Laurent Edna Waithaka Evans Lomodei 《Lakes & Reservoirs: Research and Management》2020,25(3):326-333
The common carp (Cyprinus carpio) is an exotic fish, being one of the commercially important species in Lake Naivasha. The present study investigated its growth, mortality, maturity, condition and exploitation. Sampling was done monthly from January to December 2017 with gillnets of 2–5 inches mesh size. Each individual fish was measured (cm) and weighed (g) in the field. The specimens were preserved in ice and transported to the laboratory for analysis of maturity. The fish lengths ranged from 12.0 to 69.0 cm TL, and weighed between 32 and 6,840 g. The overall population sex ratio was 1:1.66 (female:male). The length at first maturity (Lm50) was calculated to be 54.0 and 49.0 cm for females and males, respectively. The length at first capture (23.9 cm) was lower than its length at first maturity, suggesting the capture of immature fish. The mean condition factor for all fish was 1.05. The peak condition values were observed during April (1.35), September (1.59) and October (1.80). The highest (1.377) mean condition was observed for size class 56–60 and the lowest (0.933) in class 26–30. The asymptotic length (L∞) was 73.5 cm, and the growth curvature (K) was 1.05 year‐1, with a growth performance index (Ф) of 3.72. The total (Z), natural (M) and fishing (F) mortality coefficients were 2.85, 1.34 and 1.78 year‐1, respectively. The exploitation rate (E) of 0.57 year‐1 was higher than the optimum sustainable yield (E0.5) of 0.32, but was not different from the maximum sustainable yields (Emax) 0.54 and economic yield (E0.1) 0.46. The results of the present study provide parameters of fish biology and population that should prove useful in managing the fishery of Lake Naivasha. 相似文献
10.
Dr. Hiroshi Hori 《国际水》2013,38(1):116-118
Abstract After the great drought of the 1980s, the waters of the Nile River returned in abundance during the last decade of the 20th century; however, the peoples of the Nile Basin are reproducing at a greater rate than the waters of the Nile. The claims to this scarce resource are based on history and equity, which are fundamentally incompatible. Despite the creation of basin state organizations for discussion, conferences, and the intervention of the World Bank, the ten basin states, particularly Egypt, are determined to construct their own projects for Nile Control to feed their citizens in the new millennium. 相似文献
11.
Rajeev Raghavan M. R. Ramprasanth Anvar Ali Neelesh Dahanukar 《Lakes & Reservoirs: Research and Management》2018,23(3):250-255
The Western Ghats of India harbours an exceptional diversity of endemic freshwater fishes, which are threatened because of various anthropogenic stressors, including biological resource use. Lack of organized studies on the population dynamics and exploitation levels of endemic species, however, has hindered the development and implementation of systematic conservation action plans in this region. This is especially true for large cyprinid fishes threatened because of overharvest. This study examined length–weight relationships and length‐structured population dynamics of an endemic large cyprinid (Hypselobarbus kurali), based on data obtained from an artisanal gill‐net fishery in Malampuzha Reservoir. Length–weight analysis suggested the fish exhibited significantly lower exponents than expected under isometry, indicating the growth of H. kurali in the reservoir was negative allometric. The von Bertalanffy growth formula fitted to the length‐frequency data indicated H. kurali grew relatively slower than other large cyprinids in this region. Statistical analysis of recruitment revealed two peaks, implying the fish have two spawning bouts each year. Analysis of mortality and exploitation of the species revealed large‐sized individuals were targeted by the fishers, resulting in an exponential decline in the survivors in the virtual population analysis. Relative yield‐per‐recruit and relative biomass‐per‐recruit analysis indicated the current exploitation rate for the population was greater than the exploitation rate under which the stock would be reduced to half its unexploited biomass. Further, the current exploitation level was more than 60% of the expected maximum exploitation above which the population could collapse. The results of this study identify a serious need to develop and implement management plans to guide the future sustainability of the reservoir fishery of H. kurali. 相似文献
12.
Salman M.A. Salman 《国际水》2013,38(1):17-29
Disputes between Egypt and Sudan on the one hand and the Nile upper riparians on the other hand have dominated the Nile Basin for the last half-century. Nevertheless, there have been attempts at cooperation, and they culminated in the establishment of the Nile Basin Initiative and negotiation of the Nile Basin Cooperative Framework Agreement (CFA). Ironically, the CFA resulted in solidification of the areas of differences and the emergence of the upper riparians as a power to be reckoned with. This article discusses the areas of difference over the CFA and analyzes its current status and the prospects for cooperation. 相似文献
13.
The Nile perch fishery sector in Tanzania is important for enhancing the livelihoods and food security for the majority of people living near the Tanzanian portion of Lake Victoria. Despite continued government efforts and other institutions, including the Food and Agriculture Organization (FAO), Lake Victoria Fisheries Organization (LVFO), European Union and World Bank regarding the management of Lake Victoria, the Nile perch fishers have remained relative inefficient in regard to improving their fish catches. The Nile perch small‐scale fisheries sector in particular faces a challenge regarding how to improve production performance while, at the same time, ensuring a sustainable level of fisheries resources. This reality necessitates the measurement and analysis of artisan fishers’ technical efficiency. Accordingly, the present study analyses Nile perch fishers technical efficiency, using a stochastic production frontier (SPF) model based on the sample of 268 Nile perch fishers in the Tanzanian portion of Lake Victoria. The translog stochastic frontier model results indicate the technical efficiency of Nile perch fishers range between 61% and 80%, with an overall average technical efficiency of 75%. This finding implies that, based on existing fishery resources, the current quantity of Nile perch catch can be improved efficiently by 25%, a reality highlighting mismanagement of the lake's fishery resources. The quantity of bait and petrol and the number of hooks used per trip are the most important fishing inputs, indicating a positive Nile perch fishing output–input elasticity. To address the Nile perch fisher inefficiency, it is important to provide subsidized inputs such as outboard engines and mesh gillnets. Provision of access to affordable credits will enable fishers to purchase less destructive fishing inputs and improve the current structure of fishery organizations. 相似文献
14.
《Journal of Great Lakes research》2020,46(5):1113-1130
Speciation of fish in the African Great Lakes has been widely studied. Surprisingly, extensive speciation in parasites was only recently discovered in these biodiversity hotspots, notably in monogeneans (Platyhelminthes) from Lake Tanganyika. Diplectanum is a monogenean genus of which only a single species is known from the Great Lakes: Diplectanum lacustre (Diplectanidae) living on lates perches (Latidae) of Lake Albert. Despite their primary marine origin, latids have diversified in African freshwaters including several Great Lakes. In better-studied marine diplectanid species, incongruence between morphological and genetic differentiation was documented. As freshwater systems provide more opportunities for speciation than the marine realm, we ask whether diplectanids of Lates spp. of the Great Lakes underwent similar diversification as their hosts. Fresh and museum specimens of five African latid species (Lates angustifrons, L. mariae, L. microlepis, L. niloticus, L. stappersii) were examined for the presence of monogenean gill parasites. Monogeneans were characterised morphologically via morphometrics of sclerotised structures and genetically using nuclear and mitochondrial markers. Continuous morphological variation was documented in these parasites. In addition, the genetic distance, based on the COI region, between parasites of geographically isolated host species did not reach the level typically associated with distinct diplectanid species. Therefore, a single species of a newly described genus, Dolicirroplectanum lacustre gen. nov. comb. nov. is suggested to infect latid species in the examined basins. We discuss this parasite’s failure to diverge in the light of the congruence between the rate of molecular evolution in COI and host historical distribution. 相似文献
15.
Abstract The purpose of this paper is to provide an initial assessment of Egypt's plan to resettle population from the Nile Valley to the Western Desert. Known popularly as the Toshka Project, it is formally titled the National Project for the Development of Upper Egypt (NPDUE). The resettlement scheme is entirely dependent on the provision of a reliable source of freshwater. This water will be taken from Lake Nassar, behind the Aswan High Dam, and pumped through a series of canals into the desert, thereby allowing for irrigated agriculture. Through an extensive review of government documents and interviews with both government officials and Egyptian residents (who might be asked to move to the desert), we were able to develop a basic understanding of the project and a preliminary assessment of its potential for success. This was accomplished despite the paucity of published information about the project. To assess the possible success of the project, we looked at six key factors: economic, donor investment, demographics, water availability, technical, and environmental. In the end, it appears that the success of the Toshka project is highly dependent on a continued source of private capital. This capital is expected to come from other Arab countries, and, to date, the major investor in Toshka is Saudi Prince Al Walid. The Egyptian government claims that public investment in the project will be no more than 20 to 25 percent of the total, and adhering to this claim will be important; higher levels of public investment are likely to increase inflationary pressures in the country. The paper concludes with an assessment of whether the potential impacts of the project—whether economic, demographic, or environmental—are likely to offset the projected benefits of resettling seven million people out of the densely populated Nile Valley. 相似文献
16.
Orlando R. Laíz Averhoff 《Lakes & Reservoirs: Research and Management》1999,4(1-2):75-83
Cuba is located between 19°49' and 23°18' north latitude and 74°08' and 84°57' west longitude. It is the largest island in the Caribbean Sea and the paucity of natural lakes and the prolonged dry season makes it necessary to construct reservoirs. During the past 36 years, Cuba has built 220 large reservoirs (> 100 ha) and 800 smaller ones (< 100 ha). Reservoirs are the most important standing waters in Cuba and their fish, although of low diversity, support productive fisheries, with tilapias contributing 92% of the total production by weight. The fisheries in reservoirs located in the eastern and central parts of the island were analysed during the period 1983–92. The mean depth (z) of reservoirs here is 5.9 m, ranging from 1.8 to 16.0 m. The best correlation coefficients and fit regression in 54 Cuban reservoirs were between FY (fish yield) and DE (diversity of exploitation); when data were analysed with a multiplicative statistical model, r = 0.70, FY = 4.795 DE0.9292 ; and between TC (total catch) and A (area), but in this case data were analysed with a linear statistical model, r = 0.91, TC = 17209A–6635.56. Regression between FY versus z was relatively low and inverse, r = −0.20, FY = 249.145–11.04z, although all regressions were statistically significant ( P < 0.01). 相似文献
17.
Harry Verhoeven 《国际水资源开发杂志》2015,31(3):360-374
Thinking of the interconnections between water, food, energy and climate is nothing new in the Nile Basin; it has long been anchored in political struggles. For 200 years, Egypt's political economy has been defined by water use patterns and food security strategies that debunk the technocratic myth that rapid growth, interaction with global markets and technological modernization eliminate poor governance practices and allocative inefficiencies. In contrast, the prism of the nexus as a political commodity illuminates one of modern Egypt's most consequential dialectics: the interaction between the very particular nexus at the heart of the country's political economy, forged through factional strife and sustained by outside discourses and interests, and the economic and ecological ravages of this elite politics. Egyptian history serves as a warning. Today's conversation needs to be deconstructed in terms of how different forms of interconnectivity between water, energy and food are produced and experienced by different social groups. It reminds us to take interconnections not as given, but rather as contested and contestable outcomes from which opportunities for adaptation and transformation do not naturally emerge, but need to be struggled for. 相似文献
18.
Cuba is located between 19°49' and 23°18' north latitude and 74°08' and 84°57' west longitude. It is the largest island in the Caribbean Sea and the paucity of natural lakes and the prolonged dry season makes it necessary to construct reservoirs. During the past 36 years, Cuba has built 220 large reservoirs (> 100 ha) and 800 smaller ones (< 100 ha). Reservoirs are the most important standing waters in Cuba and their fish, although of low diversity, support productive fisheries, with tilapias contributing 92% of the total production by weight. The fisheries in reservoirs located in the eastern and central parts of the island were analysed during the period 1983–92. The mean depth (z) of reservoirs here is 5.9 m, ranging from 1.8 to 16.0 m. The best correlation coefficients and fit regression in 54 Cuban reservoirs were between FY (fish yield) and DE (diversity of exploitation); when data were analysed with a multiplicative statistical model, r = 0.70, FY = 4.795 DE0.9292 ; and between TC (total catch) and A (area), but in this case data were analysed with a linear statistical model, r = 0.91, TC = 17209A–6635.56. Regression between FY versus z was relatively low and inverse, r = −0.20, FY = 249.145–11.04z, although all regressions were statistically significant ( P < 0.01). 相似文献
19.
阿斯旺大坝的泥沙效应及启示 总被引：6，自引：1，他引：6
阿斯旺大坝修建已经30多年了。本文着重介绍阿斯旺大坝带来的库区泥沙淤积，下辨河道演变和河口海岸的变化，以及采取的治理措施。结合我国大型水利工程建设，阐述阿斯旺大埂给我们的启示。 相似文献
20.
Dalia Abdelhady Karin Aggestam Dan‐Erik Andersson Olof Beckman Ronny Berndtsson Karin Broberg Palmgren Kaveh Madani Umut Ozkirimli Kenneth M. Persson Petter Pilesj 《Journal of Contemporary Water Research & Education》2015,155(1):73-82
The soon‐to‐be completed Grand Ethiopian Renaissance Dam (GERD), which will be the largest hydroelectric power plant and among the largest reservoirs in Africa, has highlighted the need for expanding traditional integrated water resources management to better include the cultural, social, and political complexities of large water infrastructure in development projects. The GERD will store a maximum of 74 billion cubic meters of water corresponding to approximately the average annual outflow of the Nile from the Aswan high dam. Undoubtedly, the GERD will be vital for energy production and a key factor for food production, economic development, and poverty reduction in Ethiopia and the Nile Basin. However, the GERD is also a political statement that in one stroke has re‐written the hydropolitical map of the Nile Basin. The GERD has become a symbol of Ethiopian nationalism or “renaissance” (hidase in Amharic). A contrasting concept to nationalism is hydrosolidarity. This concept has been put forward to better stress equitable use of water in international water management challenges that would lead to sustainable socioeconomic development. We use the opposing notions of nationalism and hydrosolidarity at three different scales, everyday politics, state policies, and interstate and global politics to analyse some aspects of the new hydropolitical map of the Nile Basin. We argue that nationalism and national interests are not necessarily negative standpoints but that there may instead be a meeting point where regional and national interests join with hydrosolidarity principles. We believe that this meeting point can maximize not only the common good, but also the good from a national interest point of view. For this, it is important not increase collaboration instead of being locked in to the historical narrative of nationalistic culture and historical discourse. This would benefit and improve future sustainability. 相似文献