Struggle in the flood: tree responses to flooding stress in four tropical floodplain systems

This review examines species diversity and structural, physiological and biochemical characteristics associated with survival of annual deep flooding of trees in four contrasting tropical floodplain ecosystems

Vegetation changes after single fire-events in the Okavango Delta wetland, Botswana

A comparative study on burned and unburned areas has been conducted for the south-eastern floodplains of the Okavango Delta wetland, Botswana to assess differences in vegetation composition and structure after single fire-events. Main findings on plant traits and species occurrences supported the theory of only slight vegetation changes after fire in fire-prone environments. No specific plant trait was found to be favoured by the fire-event and only Urochloa mosambicensis showed a highly significant correlation to burning. Main changes were observed in vegetation structure, e.g. height and cover of the herb layer or biomass production. Interestingly, no main trends regarding how vegetation structure is generally affected by fire-events were derivable. Detailed analyses of five derived habitat types clearly showed different and contradictory responses to burning. This variability of vegetation response to fire-events, dependent on the habitat, was explained along a productivity gradient from active floodplains to dry Mopane woodlands. While floodplains showed an obvious decrease of standing biomass after the fire-event, an increase of biomass was observed for the Mopane woodlands. The nutrient pulses often described after fire-events, therefore seem to improve nutrient conditions best in poorer habitats, while for more productive sites, the enhanced nutrient availability after burning seem to be minor. Nomenclature: Arnold and De Wet (1993)

Enhancing the science-policy-practice nexus for effective and sustainable wetland Management in Southern Africa

&amp;lt;p&amp;gt;Effective natural resources management, especially of wetlands, are vital for the sustainability of livelihoods. This is further buttressed in Southern Africa where competing uses and users are increasingly putting pressure on these finite resources. The Southern African Science Service Centre for Climate Change and Adaptive Land Management (SASSCAL) with financial support from the African Union and the European Commission in the framework of the GMES programme endeavoured to develop a geoportal tool for effective wetland Management through a project called Wetland Monitoring and Assessment Service for Transboundary Basins in Southern Africa (WeMAST). WeMAST has an emphasis on capacity building and awareness raising for wetland assessment and monitoring in the following four transboundary river basins (Cuvelai, Okavango, Limpopo and Zambezi) across the SADC region. The WeMAST geoportal, developed during phase one, provides hydro-meteorological and physiographic attributes assessment and monitoring of wetlands. These include the spatial and temporal extent and status of wetlands, land cover and uses dynamics, flooding, vulnerability and fire indices. For the second phase, WeMAST puts emphasis on developmental impact on the ground hence some deliberate efforts are in place in order to enhance synergies between the scientists behind the concepts, the users, private sector and local communities on the ground as well as policy makers with the overall responsibilities of guiding the implementations of developmental pathways. In Phase II, policy and decision makers in the target countries (Angola, Botswana, Namibia, South Africa, Zambia and Zimbabwe) need to support upscaling and operationalization of the WeMAST geoportal. &amp;amp;#160;As a result, the project consortium has now been designed in order to foster more interactions between stakeholders involved in wetland management through knowledge brokerage events where the geoportal tool, its products and services are disseminated, tested and validated to a great extent. Similarly an interface with policy makers has been established within the consortium through WaterNet via the Water Resources Technical Committee (WRTC) in order to appraise and involve SADC ministers in charge of water and natural resources management twice annually. The innovative and well-crafted approach of the WeMAST project under GMES offers a considerable room for enhanced synergies between policy makers, Scientists, the private sector and practioners for sustainable and effective wetland Management in the SADC region.&amp;lt;/p&amp;gt;</jats:p