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1. Definition
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Name
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SHANNON'S
DIVERSITY INDEX
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Brief definition
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Shannon’s
diversity index is a measure of the variety of land
uses in an area.
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Unit of measure
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Dimensionless
index that indicates the number of different classes.
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Spatial scale
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Local
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Temporal scale
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2. Position within the logical framework
DPSIR
3. Target and political pertinence
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Objective
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Description of the state of the
resources and the environment. Identification and
mapping of ESAs.
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Importance with respect to desertification
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A greater land use diversity (in terms of small
and contiguous plots of different land uses) generally
impliesa smaller risk of land degradation and higher
biodiversity.
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International Conventions and agreements
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Secondary objectives of the indicator
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To use the indicator
in a Multicriteria Decision Analysis model to study
the driving forces (including policies) involved in
the processes that lead to desertification and the
efficiency of the responses to combat them.
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4. Methodological description and basic
definitions
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Definitions and basic concepts
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A diversity index
is a mathematical measure of species variety in a
community or land uses variety in a certain area.
It provides more information than the richness or
the number of existing land uses, it also takes the
relative abundances of different land use types into
account.
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Benchmarks Indication of the values/ranges
of value
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Methods of measurement
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Calculating the
index to each pixel and its neighbours in a raster
map of land uses.
The
index is:
Pi
= (number of polygons of “i” land use
type) / (total number of polygons S)
To calculate
the index a land use map in digital format is required.
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Limits of the indicator
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It is necessary
to have enough resolution in the maps to avoid the
loss of information.
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Linkages with other indicators
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Vegetation
cover, Erosion
protection
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5. Evaluation of data needs and availability
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Data required to calculate the indicator
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Raster land use
maps. (We have used a 100 m resolution map to calculate
the Shannon index in a 7x7 pixels area).
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Data sources
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A land use map.
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Availability of data from national
and international sources
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Data can be obtained from various
regional, national or international institutions involved
in the collection and elaboration of field or remote
data.
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6. Institutions that have participated
in developing the indicator
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Main institutions responsible
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Universidad
Politécnica de Madrid (Madrid, Spain).
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Other contributing organizations
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Fundación Universidad Empresa de Murcia (Murcia,
Spain).
Dirección General para la Biodiversidad (Ministerio
de Medio Ambiente Spain).
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7. Additional information
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Bibliography
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BACHMANN P., KOHL M. and PAIVINEN R. (1998): “Assessment
of Biodiversity for Improved Forest Planning”.
Proceedings of the Conference on Assessment of Biodiversity
for Improved Planning (1996, Monte Verità, Switzerland).
European Forest Institute nº 18. Kluwer Academic Publishers.
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Other
references
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DGCN (2001): “Tercer Inventario Forestal Nacional”.
Banco de Datos de la Naturaleza. Ministerio de Medio
Ambiente. Madrid.
ENNE, G. and ZUCCA, C. (2000): “Desertification
Indicators for the European Mediterranean Region”.
ANPA, Rome.
MAGURRAN, A. (1988):
“Ecological Diversity and its Measurements”.
Princeton University Press.
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Contacts name and address
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Joaquín Solana Gutiérrez
Universidad Politécnica de Madrid
jsolana@montes.upm.es
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