Wetland

Flooding and torrents are a seasonal phenomenon that hit a lot of cities every year around the world. As climate changes affect the world, cities are increasingly exposed to such threats especially those located on flood streams are most exposed to damages in the winter and the flooding season. In the past ten years, Egypt has been facing severe climate change effects like the increasing frequency of flooding in Egyptian cities. According to the Egyptian government, there are more than 1200 Egyptian cities and villages on flood streams and torrent tracks. These cities are distributed between the Mediterranean coast, Cairo region, Red Sea coast, Sinai and Upper Egypt, these and increasingly vulnerable towards the floods and their urban life is severely affected weather in old cities or in new planned cities. It is mostly located in the Eastern Desert at the east of the Nile. According to geologists and Meteorologists, these cities and their inhabitants are facing future hazards if th...

This study was undertaken to compare the population of avifauna of Jiwani Coastal Wetlands Complex and Taunsa Barrage Wetland. In one year study period the number of species recorded at Jiwani Coastal Wetland was 109, representing 16 orders and 38 families and at Taunsa Barrage was 110 which belongs to 45 families. At Taunsa Barrage Ardeidae remain dominant while syllviidae were the family which has greatest bird species found at the study site. The family Oriolade had only one bird species, while out of 110 species, 66 were resident, 8 were breeding resident, 34 were winter visitor and only 2 were summer visitor. At Jiwani Coastal Wetland out of 109 bird species, 77 species were migratory and 32 species were recorded as resident. The common species found at both the study sites were 49. The most critical threat facing the birds is the destruction and fragmentation of habitat. Fishing activities and illegal hunting by local people are also the major threats to the avifauna

We predict the decadal change in position of three American Samoa mangroves from analysis of a time series of remotely sensed imagery, a geographic information system, tide gauge data, and projections for change in sea-level relative to the mangrove surface. Accurate predictions of changes to coastal ecosystem boundaries, including in response to projected relative sea-level rise, enable advanced planning to minimize and offset anticipated losses and minimize social disruption and cost of reducing threats to coastal development and human safety. The observed mean landward migration of three mangroves' seaward margins over four decades was 25, 64, and 72mma−1, 12 to 37 times the observed relative sea-level rise rate. Two of the sites had clear trends in reductions in mangrove area, where there was a highly significant correlation between the change in position of the seaward mangrove margin and change in relative sea-level. Here it can be inferred that the force of sea-level rise relative to the mangrove surface is causing landward migration. Shoreline movement was variable at a third site and not significantly correlated with changing sea-level, where it is likely that forces other than change in relative sea-level are predominant. Currently, 16.5%, 23.4%, and 68.0% of the three mangroves' landward margins are obstructed by coastal development from natural landward migration. The three mangroves could experience as high as a 50.0% reduction in area by the year 2100. A 12% reduction in mangrove area by the year 2100 is possible in the Pacific islands region.

At the end of 2019 the Chilean National Congress approved the
Urban Wetland Act, which constitutes an interesting instrument to protect the
wetlands in the coastal cities. The present communication begins with a brief
exposition of the international legal framework of the wetlands. Later, it focuses
on the protection of the coastal wetlands, to conclude relating the new Urban
Wetland Act with the Chilean coastal cities’ reality. Special note will be given to
the role of the local governments in the protection of these fragile ecosystems.

ECOLOGICAL DIAGNOSIS AND EVALUATION OF BIOLOGICAL RESOURCES IN LAKE AYATA (OUED RIGH VALLEY: NORTHERN ALGERIAN SAHARA).
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ABSTRACT: Ayata Lake (155 ha) belongs to the complex of wetlands of Oued Righ Valley in Algerian Lower-Sahara. This study conducted between October 2009 and June 2010 has allowed a bioecological characterization of both biotic and abiotic elements of the site.
Flora and fauna Inventories have revealed existence of 13 plant species, 03 fish, 02 amphibians, 06 reptiles, 55 birds and 07 mammals. The flora of the site is mapped then the dynamics of dominant plant species is assessed by GIS software. Bio-ecological Statuses (faunal, trophic, phenological and protection) are attributed to the species surveyed and they are discussed. The spatiotemporal occupation of the lake by birds is mapped and detailed. Furthermore, this study includes a general review on wetlands ecosystems. Wetlands of the Lower-Sahara region (Ziban, Souf, valley of Oued Righ, and Ouargla) are inventoried, classified and mapped. This approach helped to highlight the biological resources of Ayata Lake and determine its actual ecological value. This can lead to propose suggestions for management and conservation close to its socioeconomic status in a sustainable development view.

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RÉSUMÉ: Le Lac Ayata (155 ha) appartient au complexe des zones humides de la Vallée d’Oued Righ au Bas-Sahara algérien. L’étude menée entre octobre 2009 et juin 2010 a permis une caractérisation bioécologique des éléments tant biotiques qu’abiotiques du site. Les inventaires de la flore et de la faune ont révélé l’existence de 13 espèces végétales, 03 poissons, 02 amphibiens, 06 reptiles, 55 oiseaux et 07 mammifères. La flore du site est cartographiée et la dynamique saisonnière des espèces dominantes est estimée par un logiciel de SIG. Des statuts bioécologiques (fauniques, trophiques, phénologiques et de protection) sont attribués aux espèces animales inventoriées puis ils sont discutés. L’occupation spatiotemporelle du lac par l’avifaune est cartographiée et détaillée. Par ailleurs, cette étude comporte des connaissances générales sur les des zones humides. Celles-ci sont inventoriées, classifiées puis cartographies dans la région du Bas-Sahara (Ziban, Souf, Vallée d’Oued Righ et Ouargla). Cette approche a permis de mettre en valeur les ressources biologiques du site et de déterminer son importance écologique. Ceci peut aboutir à des suggestions de gestion et de conservation étroites à son état socioéconomique dans une prospection d’un développement durable.

Dhaka City has been suffering from many environmental problems including flooding, waterlogging and other related problems. Urbanization, which is occurring very fast and with larger magnitude in Dhaka, is the intrinsic reason behind these problems. High rate of urbanization causes extensive urban area expansion and as a result canals, wetland and other
water bodies are quickly vanishing from the landscape. This study shows the present physical condition of the canals; identifies the processes of canal encroachment; represents the
consequences of canal encroachment. 13 canals of 50 were surveyed; local people were surveyed to identify the impact and processes of encroachment. According to this study, canals of Dhaka city are under serious threat of extinction and require immediate recovery actions. Canals are being encroached in various styles and this study identifies five: unauthorized land
filling, illegal construction over canal, expansion of slum, solid waste dumping, taking advantage of lack of awareness of local people as well as government agencies. However, this study also discusses the grave consequences of canal encroachment: increasing flood vulnerability, wane of ground water recharge area and ground water level, collapse of natural drainage system, loss of local ecology and biodiversity.

The first aim of this invited literature review is critically to review and evaluate hydrological, physical and biochemical processes within natural and constructed wetlands. The second aim is to contribute the thoughts of the authors to the discussion with the help of a case study focusing on gully pot liquor treatment. The performances of constructed treatment wetlands with and without

Wetlands are lands where saturation with water is the dormant factor determining the nature of soil development and the types of plant and animal communities living in the soil and on its surface. The single feature that most wetlands share is soil or substrate that is at least periodically saturated with or covered by water. The water creates severe physiological problems for all plants and animals except those that are adapted for life in water or in saturated soil.

Wetlands are the most productive ecosystems on earth’s surface. Ramsar Convention puts forward binding regulations to protect wetlands across the globe. The real situation however, is different and
complex. These fragile ecosystems are under imminent threat from natural and anthropogenic stress
factors. Son Beel Wetlands of Assam in North East India is also no different. The health of this
wetland is steadily deteriorating as a result of a series of internal as well as external factors. Valuation
of the wetland is important to understand the need for conservation and sustainable development. The
beneficial future prospects of the wetland are further discussed in this chapter which can be facilitated
with the help of cutting-edge technologies such as nanotechnology

From the wetlands of Nadia district as many as 42 species of angiosperms belonging to 26 families and 2 species of pteridophytes were observed which are locally used for various purposes. Of these plants, 30 species have excellent medicinal properties.

"Wetland is a collective term for ecosystems formed by water and processes and its characteristics are mainly controlled by water. A wetland is a place that is sufficiently long for the growth of vegetation and other specially adapted organisms (Maltby, 1986). Wetlands are defined based on 3 parameters, namely Hydrology, hydrophilic vegetation, and wet soil (Cassel, 1997). One type of wetland that can be utilized is artificial wetlands. Currently, wetlands can be used and manipulated to control pollution through a Biofilter system.