Managing river basin for wetlands
Wetlands also perform many other important socio-economic functions, such as provision of habitat for fisheries and forestry resources, and are critical for the conservation of biological diversity.
River basins or river catchments (the land area between the source and the mouth of a river including all of the lands that drain into the river) and coastal and marine systems influenced by catchments’ discharges, are important geographical units for considering the management of wetlands and water resources.
Rapid unsustainable development of wetlands and the river basins has led to the disruption of natural hydrological cycles. In many cases this has resulted in greater frequency and severity of flooding, drought and pollution. The degradation and loss of wetlands and their biodiversity imposes major economic and social losses and costs to the human populations of these river basins. Thus, appropriate protection and allocation of water to wetlands is essential to enable these ecosystems to survive and continue to provide important goods and services to local communities.
In the coming years, demands on water resources will continue to increase, as will the levels of pollutants. In order to achieve the goal of sustainable utilisation of freshwater resources, new approaches to water and river basin management are urgently required.
In the past, the water resources and wetlands have tended to be the responsibility of separate sectoral agencies, frequently with very different objectives and modes of operation. As a result there have been regular conflicts over water resource use and river basin management. Regrettably, in these considerations wetlands have not always been given the priority they deserve based on the important functions they perform in contributing to the maintenance of healthy and productive river systems.
Integrated water resources management is based on the concept of water being an integral part of an ecosystem, a natural resource and a social and economic good, whose quantity and quality determine the nature of its use (Agenda 21, United Nations, 1992). A water source that is reliable, in terms both of its quantity and its quality, is a prerequisite for the survival of human civilization and socio-economic development.
Water scarcity, gradual deterioration, aggravated pollution and infrastructure development has increasingly created conflicts over the different uses of this resource. The river basin management approach is an example of an incentive-based participatory mechanism for solving conflicts and allocating water between competing users, including natural ecosystems.
Another key issue is the lack of awareness of the cross-sectoral nature of water problems and the need for a new development paradigm towards integrating the technical, economic, environmental, social and legal aspects of water management. The development of administrative units in water resource management has to coincide with river basins’ boundaries instead of political boundaries. The lack, or inadequacy, of water legislation and policies is another major constraint for integrated management of river basin and optimal use of water resources.
An essential component of river basin management is knowledge of both current and future supply and demand upon water resources in a river basin, taking into consideration the possible impacts of climate change. Current and future assessments of the resource need to focus on the human uses of water (such as irrigation, hydro-electricity and domestic or industrial water supply) as well as the ecological needs for water within different parts of a river basin. In this respect, water demands should not only be defined in terms of water quantity but also water quality.
Ecological water demands are less obvious and more difficult to quantify and consequently have often been ignored or underestimated in terms of water demand. Ignoring such requirements may lead to major environmental and social problems such as collapse of fisheries or downstream sea intrusion. It is also important to recognise that the greatest damage to the environment may occur during extreme events rather than the average situation.
Wetlands ecosystems depend on the maintenance of the natural water regimes such as flows, quantity and quality, temperature and timing to maintain their biodiversity, functions and values. The natural flow regime can be considered the most important variable that regulates the ecological integrity of riverine wetlands ecosystems.
The construction of structures that prevent the flow of water, and of channels that carry water out of the floodplain faster than would occur naturally, result in the degradation of natural wetlands and eventual loss of the services they provide.
An important element within the concept of integrated river basin management is that planning and management institutions work with and for the entire community of water users in the basin, including wetlands wildlife and users, as well as relevant stakeholders outside the river basin.
Pakistan is blessed with about 225 significant man-made and natural wetlands spread over approximately 10 per cent of the country. Lakes, canals, dams and lagoons formed as part of Pakistan’s extensive Indus Basin Irrigation System are classified as man-made wetlands.
Wetlands and their resources make a significant, though largely unrecognised, contribution to the economy. Both freshwater and marine fish, for example, form a noteworthy portion of fish production and exports. Further, they provide livelihoods for several rural communities such as fisher folk, hunters, graziers and forest users living close to wetlands.
Various wetlands products are used by the people on a daily basis. Fish and fish products, baskets, blinds and reed mats and herbal medicines comprise just a few examples of these products. Rural people, especially poor households, also extract and process wetlands material for meeting daily needs.
Wetlands support a broad spectrum of important plant species and invertebrate and vertebrate animals. The latter includes a range of threatened, endemic and endangered species: five species of mammals, nine bird species, six forms of reptile, and about six freshwater, estuarine and marine fish types. Several of these animals are world famous such as the Indus dolphin, Punjab urial, marsh crocodile and green and olive Ridley turtles. Many types of migratory birds including white-headed duck, Siberian cranes, Sarus cranes, greater flamingos and spot-billed pelicans use wetlands as wintering grounds.
The wetlands are generally degrading due to a whole range of human– induced threats such as conversion of wetlands and their immediate surroundings for agriculture and other purposes, damming of rivers and changes in water flow regimes, over harvesting of many forms of wetlands resources, felling of timber and deforestation of catchments’ areas, organic and inorganic pollution of wetlands, policy deficiencies and inadequate management.
Impact of climate change on the wetlands has to be documented, as sharp decline in the migratory birds is being reported, particularly in Sindh. Pakistan being a signatory to the Ramsar Wetlands Convention has obligations to undertake several initiatives to conserve and promote sustainable use of wetlands within the framework of the River basin management.
A large number of Ramsar sites are located in Sindh including Keenjhar, Haleji, Indus Delta in the Thatta district, Runn of Kuchch and Narriri-Jubbo Lagoon in Badin, Deh Akro in Benazirabad district, Drigh in Larkana district and the Indus Dolphin Reserve from the Sukkur barrage upstream Guddu barrage near Kashmore and the Hub dam.
The situation of Ramsar sites is quite dismal. One of such sites includes the Narriri-Jubbo lagoon in Badin district, which has completely vanished and if measures are not taken for its rehabilitation, the Ramsar secretariat may consider de-listing this site.