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| Mapping of Natural Resources for Agriculture Use and Planning in Libya |
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This project was initiated by the Government of Libya, FAO and the
United Nations Development Programme (UNDP) to strengthen
the capacity of the General People's Committee for Agriculture, Animal
and Marine Wealth (GAAAMW) to manage land resources at national and
sub-national levels through the establishment of a strategy, and a spatially
based operational decision support system - the Land Resources Information
Management System (LRIMS).
LRIMS
Assessment and modelling of land suitability and responses to
potential agricultural process is the final and ultimate aim of the
project. This is being achieved through the development of the Land
Resources Information Management System (LRIMS) for Libya.
LRIMS is a platform on which information from various sources can be
integrated, analysed and processed to develop the data and information
for technicians and policy makers required to undertake suitable ecologically
and socio-economically sustainable development practices.
LRIMS integrates various functionalities and methodologies into one processing
environment (ArcGIS and Spatial Analyst). It enables standardization
and the creation of harmonized complex databases.
Land cover product
As part of the LIB/00/004 project, a land cover product was developed by
FAO. The map scales used for the compilation of the spatial data were
1:50,000 and 1:100,000. The first scale was used to characterize
agricultural areas with a mean annual rainfall equal or above 200 mm
and the second scale was used to define rangeland areas with a mean
annual rainfall between 50 and 200 mm and bare areas, which are mainly in the
southern part of the country.
Accuracy Assessment
The land cover database developed for Libya was validated through an
accuracy assessment which consisted of undertaking field surveys
across the whole country. Five field work campaigns were undertaken
to carryout the in situ validation of 250 polygons. Each point was
reached using GPS technology.
The sum of points collected during the different field trips for the
verification, the accuracy assessment and the change assessment,
generated a database consisting on 5 288 points.
The results of the field surveys confirmed the quality of the land cover
database developed: 74% of samples with a correct interpretation; 18% of
samples with a wrong interpretation; 5% of samples with a correct Main
group but with a wrong User Label, and 3% of not definable points.
Change Assessment
A land cover change assessment was also undertaken by a comparative
change-detection analysis of the satellite data 1980s, 1990s and 2000s.
Four areas were selected as study areas due to their sensitivity and economic
importance, these are:
- Tripoli (see picture above): to assess the impact of the urbanization and
to estimate the amount of tree plantation loss due to
anthropic factors.
- Jafara Plain: to assess the rangeland changes due to
pastoralism (overgrazing).
- Tawarga: to assess the changes of the coastal and the
sabkha areas.
- Jebel Akhdar: to assess the changes on natural
vegetation due to the anthropic impacts.
For example, the analysis provided a clear estimate of the expansion of
urbanization in the Tripoli area and indicated that the urban area of
Tripoli doubled in the last 25 years; from the 11 587 ha in 1976 to
22 534 ha in 2001. Agriculture and palm tree crops were the main areas
converted.
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