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Landscapes Forest and Global Change - ESA - Escola Superior ...

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F.M. Rabenilalana et al. 2010. Multi-temporal analysis of forest l<strong>and</strong>scape fragmentation in the North East of Madagascar<br />

91<br />

Multi-temporal analysis of forest l<strong>and</strong>scape fragmentation in the North<br />

East of Madagascar<br />

F.M. Rabenilalana 1 , L.G. Rajoelison 1 , J.P. Sorg 2 , J.L. Pfund 3 & H Rakoto Ratsimba 1<br />

1 Département des Eaux et Forêts, Ecole Supérieure des Sciences Agronomiques,<br />

Université d’Antananarivo, Madagascar<br />

2 Swiss Federal Institute of Technology Zurich, Institut of Terrestrial Ecosystems,<br />

Groupe de foresterie pour le développement, Zurich. Switzerl<strong>and</strong><br />

3 CIFOR, Center for International <strong>Forest</strong>ry Research, Bogor, Indonesia<br />

Abstract<br />

Habitat fragmentation caused by insufficient arable l<strong>and</strong> <strong>and</strong> rural poverty has become a main<br />

concern to tropical forest managers in Madagascar. In order to inform management decisions,<br />

the present study aims to provide quantitative information on the fragmentation process <strong>and</strong> its<br />

driving forces in Manompana. Therefore, time series analysis of fragmentation in relation to the<br />

spatial distribution of settlements, roads <strong>and</strong> topographic parameters was done. Results showed<br />

that (1) deforestation has been increasing due to exp<strong>and</strong>ing upl<strong>and</strong> rice production, thus<br />

progressively increasing l<strong>and</strong>scape fragmentation (2) fragmentation dynamic significantly<br />

differed with distance to paths, villages <strong>and</strong> depending on topographic characteristics. In the<br />

following these parameters will be used for spatio-temporal modeling of the l<strong>and</strong>scape<br />

dynamics to support decision making on sustainable management of natural resources.<br />

Keywords: l<strong>and</strong>scape, fragmentation, tropical humid forest, spatial analysis, Madagascar.<br />

1. Introduction<br />

Fragmentation refers to breaking a whole into smaller pieces while controlling for changes in<br />

the amount of habitat (Forman 1995, Fahrig 2003, Ewers 2006). Deforestation is one driver of<br />

habitat fragmentation. Fragmentation often results in the loss of habitat <strong>and</strong> the isolation of the<br />

remaining forest fragments. It creates matrices of human-managed areas, secondary vegetation<br />

regrowth, <strong>and</strong> fragments of primary forest (Benitez-Malvido 2003).<br />

The region of Manompana, is a disturbed tropical lowl<strong>and</strong> rainforest,forming a forest corridor<br />

between two protected areas with very high levels of endemism: the special reserve<br />

Ambatovaky in the South West <strong>and</strong> Biosphere Reserve of Mananara Nord in the North. In the<br />

region of Manompana forest clearing due to slash <strong>and</strong> burn agriculture <strong>and</strong> commercial logging<br />

are the main drivers of deforestation <strong>and</strong> thus habitat fragmentation, affecting the l<strong>and</strong>scape<br />

structure, the livelihoods <strong>and</strong> the biodiversity (Forman & Godron 1986, Andren 1992, Reed<br />

1996, Franklin 2001, McGarigal 2002, Kuppfer 2006, Jaeger 2000, Collinge 2009).<br />

This paper aims to study spatio-temporal patterns of l<strong>and</strong>scape fragmentation at a regional scale,<br />

i.e. the fragmentation of the forest ecosystem in Manompana in order to inform management<br />

decisions.<br />

Therefore, l<strong>and</strong> cover predictions for future were made using SPOT 5 multispectral, multib<strong>and</strong><br />

images (V 0,50 -0,59 μm R 0,61 -0,68 μm Near InfraRed or NIR 0,78 -0,89 μm <strong>and</strong> Mean<br />

InfraRed or MIR 1,58 -1,75 μm) with a 10 meters resolution from 2004 <strong>and</strong> 2009. Furthermore,<br />

1 Corresponding author. Tel.:+2613367162<br />

Email address: rmihajamanana@yahoo<br />

<strong>Forest</strong> <strong>L<strong>and</strong>scapes</strong> <strong>and</strong> <strong>Global</strong> <strong>Change</strong>-New Frontiers in Management, Conservation <strong>and</strong> Restoration. Proceedings of the IUFRO L<strong>and</strong>scape Ecology<br />

Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)<br />

2010, Instituto Politécnico de Bragança, Bragança, Portugal.

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