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| Deltaic Ecosystems |
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Background
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Indus River Delta |
According to the latest IPCC report "..river deltas are among
the most valuable, heavily populated, and vulnerable coastal
system in the world. Deltas develop where rivers deposit t
the shore than can be carried away by waves. Deltas are
particularly at risk for climate change, partly because the
natural processes and partly because of the human-induced stresses…."
Deltas are important physical and ecological systems that deliver
ecological services and support the economies of entire communities.
Around deltas human populations, fish and wildlife resources,
agriculture, energy development, transportation, and commerce all
converge.
Mega-deltas occurring at the mouths of the major rivers on the Earth
are believed to be especially vulnerable to ongoing sea-level rise
resulting from climate change and habitat alteration, placing human
communities at risk from flooding and cyclonic storms. Deltas are
areas where powerful fluvial forces and coastal geomorphic processes
drive landscape change over both short periods of time and entire
geological epochs.
Geologic, hydrologic, and biological processes combine to form
extremely dynamic environments, which can be altered significantly
by human actions and major coastal storms.
Goal
The deltaic systems project aims to raise awareness about threats to
deltas and provide a comprehensive, high quality base of information
on physical, environmental, ecological, and sociological threats as
an aid to the integration of science and management. Basic information
will not be limited to mapping deltaic areas, but also the changes
over time will be assessed so as to model patterns that will be
easily visualized.
GLCN and deltaic systems
FAO-Environmental Assessment and Monitoring Unit (NRCE) is proposing
a methodology for mapping land cover and assessing the change over
major deltaic systems. The project will address most of the major world
deltas, giving priority to some (in bold) of them:
| AFRICA | id |
| Mangoky, Malagasy | [23] |
| Niger, Nigeria | [26] |
| Nile, Egypt | [27] |
| Pungue, Mozambique | [33] |
| Senegal, Senegal | [37] |
| Tana, Kenya | [--] |
| Zambezi, Mozambique | [42] |
| ASIA | |
| Amu-Darya, Russia | [01] |
| Baram, Malaysia | [02] |
| Chao Phraya, Thailand | [04] |
| Ganges-Brahmaputra, Bangladesh/India | [10] |
| Godavari, India | [13] |
| Huanghe, China | [14] |
| Indus, Pakistan | [15] |
| Irrawaddy, Myanmar | [16] |
| Klang, Malaysia | [73] |
| Krishna, India | [12] |
| Lena, Russia | [18] |
| Mahanadi, India | [22] |
| Mekong, Vietnam | [24] |
| Red, Vietnam | [34] |
| Salenga, Russia | [35] |
| Shatt-al-Arab, Iraq | [38] |
| Yangtze Kiang, China | [40] |
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| OCEANIA | id |
| Burdekin, Australia | [03] |
| Fly, Indonesia | [09] |
| Klang Malaysia | [17] |
| Mahakam Indonesia | [21] |
| Ord, Australia | [28] |
| EUROPE | |
| Danube, Romania | [06] |
| Dniepr, Russia | [07] |
| Ebro, Spain | [08] |
| Pechora, Russia | [31] |
| Po, Italy | [32] |
| Volga, Russia | [39] |
| NORTH AMERICA | |
| Colville, Alaska | [05] |
| Grijalva, Mexico | [11] |
| Mackenzie, Alaska | [19] |
| Mississippi, US | [19] |
| Yukon, Alaska | [41] |
| SOUTH AMERICA | |
| Magdalena, Columbia | [20] |
| Orinoco, Venezuela | [29] |
| Paraiba | [65] |
| Parana, Argentina | [30] |
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For vulnerable areas like deltas, a comparative study of land cover
changes can help the quantification of the "disturbance" of the areas.
Land cover change is a direct measure of quantitative habitat loss or gain.
Land cover change also is a direct measure of increases or decreases
in sources of pollution, sedimentation, and other factors that
determine habitat quality. Increases in developed land, for example,
are accompanied by land disturbance that increases erosion and
sedimentation and by hydrologic alteration that increases runoff.
Similarly, cultivated land is associated with fertilizer and
pesticide inputs to the land and ultimately to the marine environment.
Hence, land cover change is linked to habitat quantity and quality.
Remote sensing from satellite can be used to extract consistent
information. Several different methods have been proposed and
applied by different scientific groups; at the moment for the
GTOS present study the protocol proposed has been choose to
accomplish the main purposes of:
- need to applied a validate the standard approach
- need to achieve a comparative database for different worldwide deltas system
- statistical accuracy
- rapidity
Finally, the goal of completing an accurate suitable change
detection land cover data base of delta ecosystems is the main
objective of the present study.
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