Poyang Lake basin: a successful, large-scale integrated basin management model for developing countries

Protection of water environment while developing socio-economy is a challenging task for lake regions of many developing countries. Poyang Lake is the largest fresh water lake in China, with its total drainage area of 160,000 km2. In spite of rapid development of socio-economy in Poyang Lake region in the past several decades, water in Poyang Lake is of good quality and is known as the "last pot of clear water" of the Yangtze River Basin in China. In this paper, the reasons of "last pot of clear water" of Poyang Lake were analysed to demonstrate how economic development and environmental protection can be coordinated. There are three main reasons for contributing to this coordinated development: 1) the unique geomorphologic features of Poyang Lake and the short water residence time; 2) the matching of the basin physical boundary with the administrative boundary; and 3) the implementation of "Mountain-River-Lake Program" (MRL), with the ecosystem concept of "mountain as source, river as connection flow, and lake as storage". In addition, a series of actions have been taken to coordinate development, utilisation, management and protection in the Poyang Lake basin. Our key experiences are: considering all basin components when focusing on lake environment protection is a guiding principle; raising the living standard of people through implementation of various eco-economic projects or models in the basin is the most important strategy; preventing soil and water erosion is critical for protecting water sources; and establishing an effective governance mechanism for basin management is essential. This successful, large-scale basin management model can be extended to any basin or lake regions of developing countries where both environmental protection and economic development are needed and coordinated.     

调水引流对太湖无锡水域湖流的影响

2007年望虞河和梅梁湖泵站联合引调工程，在保障太湖水源地水质水量方面取得了一定的成效。在介绍贡湖与梅梁湖湖流监测工作情况的基础上，对湖流测验结果进行了初步分析，分析了贡湖、梅梁湖湖流分布状况，风场对湖流的影响，特殊区域和位置的流场变化，得出以下结论：联合引调工程，改善了两湖水体的流动状态，特别是在梅梁湖泵站调水情况下，湖区流速明显增加，这一流动状态对贡湖取水口和梅梁湖水源地的水质改善是非常有利的。     

Effects of environmental factors on cyanobacteria dynamics in Lake Baringo,Kenya

The dominance of cyanobacterial algae in light‐limited, shallow freshwater Lake Baringo is a major environmental concern in regard to Kenyan water quality and public health protection agencies. Accordingly, this study focused on determining the effect of different environmental factors on cyanobacteria dynamics in different sediment disturbance zones of the lake and in different seasons. This study also sought to bridge the knowledge gap regarding the influence of water clarity on cyanobacteria dynamics in the lake. Samples were collected from the field, stored in ice and transported to the laboratory for nutrient analyses. Cyanobacteria cultures isolated from the lake were grown under a 12:12 light/dark cycle. The frequency of dividing cells (FDC) technique, and a fluorescence microscopy technique, was used to count growing cyanobacteria cells. Specific cyanobacteria organic carbon synthesis was significantly negatively correlated with turbidity for the southern (r = ?0.6573; P < 0.05) and central sediment disturbance zones (r = ?0.6847; P < 0.05). This study indicated that water clarity is an environmental phenomenon that facilitates the movement of cyanobacteria into the turbid areas of the lake, where their production levels are significantly high, in contrast to the clear water along the edges of the water–land interface during the wet season (April to August) and dry season (September to March). Water clarity potentially enhances cell division inhibition and multiplication, thereby positively influencing cyanobacteria dynamics in Lake Baringo. Thus, it is concluded that the cyanobacteria growth rate resulting from use of the FDC technique suggests a link with inflowing water clarity that can be used to monitor in‐lake water quality, to better manage cyanobacteria blooms in Lake Baringo and in lakes and reservoirs elsewhere.     

Planning for integrated lake management in Uganda: Lessons for sustainable and effective planning processes

The international consensus on the need for integrated approaches for managing water resources has led to a plethora of integrated frameworks and strategies. The development of management plans for lakes and their drainage basins is part of the ‘integrated management’ agenda. Challenging questions, however, arise in regard to what integration actually means within the context of planning processes and systems, and for the management plans themselves. The limited literature on lake management planning emphasizes the need for a lead agency for planning and implementation. A relevant question is how does lake management planning relate to planning by local governments, national government departments and other stakeholder groups. The integrated lake management efforts in Uganda have led to the development of lake management plans that build on, and complement, existing local government processes and plans. Lessons from early lake management experiences indicate that establishing clear linkages in the planning processes, and within the plans themselves between lake management structures and local government, is essential for sustainability, coordination and resource mobilization. The development of lake management plans also strengthens existing local government planning systems, by providing a forum for sharing information, ideas and lessons. The lake management planning also supports the introduction of local governments to participatory, community‐based planning, as well as promoting intersectoral coordination.     

An overview of the current status of Lake Victoria fishery: Opportunities, challenges and management strategies

Lake Victoria is African's most important source of inland fishery production, exhibiting an annual catch of ≈500 000 mt. The lake moderates local climate, serves as a means of transport, and a source of human food and raw material for the fishmeal industry. The introduction of Nile perch transformed the fisheries from a locally based artisanal fishery to a national and international capital investment industry. The fisheries produce an annual income of $US 600 million, providing employment opportunities for over 3 million people. Although the benefits of transforming the fishery of Lake Victoria appear to be quite remarkable, the negative impacts of this development are even more dramatic. Several challenges face the lake fishery, including environmental degradation, the introduction of exotic species, overfishing, and a fish export ban. Nutrients inputs into the lake have resulted in eutrophication and increased algal blooms. Deteriorated water quality and increased anoxia have caused the displacement and decline of some fish species. Exotic tilapiines have hybridized, displacing the indigenous fish species. Nile perch predation has caused the disappearance of once abundant native fish species. The once complex food web is now dominated by Nile perch. Unhygienic fishing methods have led to several fish export bans, while water hyacinth invasion in the lake has affected water quality, fishing and transportation possibilities. The current top‐down management and use of different regulations by the riparian states have been a major drawback to sustainable management of the lake. There is a need for a paradigm shift, in which the lake is considered to be one ecosystem and relevant stakeholders are involved in the decision‐making process.     

岱海湖温排水对湖面附加蒸发量影响研究

岱海湖为一内陆封闭型湖泊。本研究利用3、7、12月份冬夏工况,综合考虑岱海湖边界条件,水面温度、密度、水面天然温度、大气温度、相对湿度等影响因子,构建温排水对岱海湖附加蒸发量影响的计算公式。经计算,电厂温排水引起的岱海湖附加蒸发损失量为:3月份为39.46万m3,7月份为73.3万m3,12月份为10.6万m3,岱海湖电厂温排水年附加蒸发水量约为678.2万m3/a。结果表明:附加蒸发量与电厂温排水量变化一致。本研究对干旱区水资源利用具有重要意义。     

Integrated lake basin management and its importance for Lake Chini and other lakes in Malaysia

This report discusses the concept and progress of IWRM/IRBM in Malaysia, with a subsequent focus on the problems and challenges facing Lake Chini, one of the two largest freshwater lakes in the country. Lake Chini is located within the Pahang River Basin, the largest river basin in Peninsular Malaysia. The lake is a popular tourist destination, and the various infrastructure developments needed to enhance its marketability have resulted in degradation of the natural environment, as well as infestation of aquatic plants over most of the lakes' surface area. This report also discusses the need for integrated basin management as the logical approach for holistic management of the entire Pahang River Basin, in order to ensure the management of Lake Chini for sustainable use, including retention of its importance, not only for eco-tourism, but also as the source of the livelihood of the indigenous people living in the lake ecosystem and catchment area.     

Inle: A large Myanmar lake in transition

Inle Lake is situated in the southern part of Shan State in Myanmar. It is the country’s second‐largest lake, home to more than 120 000 people and a large bird sanctuary and a major source of hydroelectric power for southern Myanmar. Several distinct environmental problems have arisen in the lake basin. A long‐term decrease in lake area has taken place over the last 30 years, probably because of siltation and climate. The drought of the last 2 years in particular has caused a drop in hydroelectric power output, which is affecting southern Myanmar. Many marginal parts of the lake are occupied by elephant grass mats (Saccharum spotaneum L.), known locally as kaing. These mats mature to form solid, floating islands, which are used for a unique form of agriculture but are also an increasing source of pesticide and fertilizer runoff into the lake. Textile cottage industries also abound, and both natural and manufactured dyes are discharged into the lake. Households, including many houses built on stilts in the lake, are a source of garbage and sewage. Livestock breeding also is a source of sewage. Shifting (taungyar) cultivation and village expansion has greatly increased erosion. Dredging is now necessary in many places and water clarity has decreased. The Inle carp (Cyprinus carpio intha), known locally as nga‐phane, plays an important role in the food supply, as well as being a cultural symbol of the local Intha people. Nga‐phane population abundance is currently low, probably because of changes in water chemistry and decreased clarity in the lake water. Partially because of the perceived potential for tourism, many sectors are now involved in lake rehabilitation and management.     

Influence of influent tributaries on water quality changes in Lake Mogan, Turkey

Lake Mogan, located in the steppes of central Anatolia, is a vital Turkish ecological system, in terms of its water resources, flora and fauna. The lake also is a unique recreational area for Ankara, the capital of Turkey. However, the lake is currently threatened by severe pollution, being under the risk of serious degradation because of (i) uncontrolled urbanization; (ii) point and non‐point source pollution; (iii) inefficient sewerage systems; (iv) sediment transportation and pollution via influent creeks to the lake; (v) uncontrolled soil erosion in its drainage basin; (vi) inappropriate flood control measures; and (vii) severe degradation of the natural wetlands within its drainage basin. This study evaluates the influence of its influent creeks on the water quality of Lake Mogan, mainly because the creeks are believed to be responsible for the major pollutant load reaching the lake, and because the extensive database documenting this situation has not previously been critically evaluated. Accordingly, this study reviews (i) change in the water quality of Lake Mogan between 1993 and 2002; (ii) the water quality classification of the major influent creeks feeding Lake Mogan; and (iii) the influence of the influent creeks on the water quality of the lake between 1993 and 2004.