Definitions and Mapping of East African Wetlands: A Review <s> The Wise Use of East African Wetlands and the Need for Spatial Data <s> Ewaso Narok Swamp, formed along the Eng'are Narok river, is located in the semi-arid part of the Laikipia District, Kenya. The area, of bushy grassland, is characterised by low rainfall (less than 750 mm annually) and episodic rivers. Before the 1970s, the dominant land use was large scale ranching and nomadic pastoralism. Since 1970, this has slowly been transformed into high density small-scale farming. There has been a strong trend towards settlement along riverine and wetland areas due to their suitability for farming and easy availability of water for cultivation. Ewaso Narok swamp has a rich species diversity of over 170 bird species, resident and migrant, over 100 plant species and it also provides an important dryland refuge for both domestic and wild animals. The swamp also provides socio-economic products such as plant matter for building. The result of its land use transformation has been ecosystem alteration, habitat modification and destruction both for wetland and rangeland species. This change has also been accompanied by escalating human–wildlife conflict. However, although this process is self-destructive, the lack of economic returns from wildlife to some extent justify the land use transformation since the communities settling here have to satisfy the basic requirements of food and shelter. This poses the challenge of the developing appropriate ways to conserve the dryland wetlands whilst attaining maximum returns for the local community. <s> BIB001 </s> Definitions and Mapping of East African Wetlands: A Review <s> The Wise Use of East African Wetlands and the Need for Spatial Data <s> The Wetlands and Water synthesis was designed for the Ramsar Convention to meet the need for information about the consequences of ecosystem change for human well-being and sought to strengthen the link between scientific knowledge and decision-making for the conservation and wise use of wetlands. <s> BIB002 </s> Definitions and Mapping of East African Wetlands: A Review <s> The Wise Use of East African Wetlands and the Need for Spatial Data <s> Recent advances in remote sensing provide opportunities to map plant species and vegetation within wetlands at management relevant scales and resolutions. Hyperspectral imagers, currently available on airborne platforms, provide increased spectral resolution over existing spacebased sensors that can document detailed information on the distribution of vegetation community types, and sometimes species. Development of spectral libraries of wetland species is a key component needed to facilitate advanced analytical techniques to monitor wetlands. Canopy and leaf spectra at five sites in California, Texas, and Mississippi were sampled to create a common spectral library for mapping wetlands from remotely sensed data. An extensive library of spectra (n ¼ 1336) for coastal wetland communities, across a range of bioclimatic, edaphic, and disturbance conditions were measured. The wetland spectral libraries were used to classify and delineate vegetation at a separate location, the Pacheco Creek wetland in the Sacramento Delta, California, using a PROBE-1 airborne hyperspectral data set (5 m pixel resolution, 128 bands). This study discusses sampling and collection methodologies for building libraries, and illustrates the potential of advanced sensors to map wetland composition. The importance of developing comprehensive wetland spectral libraries, across diverse ecosystems is highlighted. In tandem with improved analytical tools these libraries provide a physical basis for interpretation that is less subject to conditions of specific data sets. To facilitate a global approach to the application of hyperspectral imagers to mapping wetlands, we suggest that criteria for and compilation of wetland spectral libraries should proceed today in anticipation of the wider availability and eventual space-based deployment of advanced hyperspectral high spatial resolution sensors. 2008 Elsevier Ltd. All rights reserved. <s> BIB003
In 2005, the World Resources Institute produced the Millennium Ecosystem Assessment Report on Wetlands and Water BIB002 . This document states clearly that wetlands are an important ecosystem resource in multiple dimensions. Complex wetland ecosystems provide "…services vital for human well-being and poverty alleviation…", including essential freshwater and energy resources BIB003 , regulation of hydrologic regimes and climatic processes and soil erosion control. The report estimates that the annual combined global value of wetlands, tidal marshes and swamp ecosystem services is US$ 44,355 ha . When compared to the values estimated for forest ecosystems (US$ 3,278  ), the critical importance of wetlands to local communities and economic systems becomes obvious. In a 2001 study examining wetlands in Kenya, Thenya BIB001 