Deciduousness; Forest management and conservation; Mixed species forest; Monodominant forest; Pioneer; Wood specific gravity
Abstract :
[en] The greater part of the semi-deciduous moist forests of the Congo basin has been given to logging companies for exploitation. In the next decades, very few of these forests will remain intact. In this paper, we aimed to identify large-scale variations in the structure, composition and functioning of African moist forests that could serve as a baseline for both management and conservation purposes. Commercial forest inventory data were assembled for 49,711 0.5-ha plots, covering an area of more than six million hectares, crossing the borders of Cameroon, Central African Republic and Republic of Congo. Floristic composition was analyzed for a subset of 176 genera reliably identified in the field. Three key functional traits of tropical trees: regeneration guild, leaf phenology, and wood specific gravity, were collected at the species
level from various sources, and assigned at the genus level. We first investigated the main variations in forest structure and composition, and identified seven forest types based on these variations. Differences in the percentage of pioneer and deciduous stems, and mean wood specific gravity were tested between forest types. Most of the study area was composed of a mosaic of the structural variations of the forests characterized by the occurrence of Celtis (Ulmaceae) species, which are mostly composed of frequent and abundant genera that formed the common floristic pool of the region. Secondary Musanga (Moraceae) forest is located in repeatedly disturbed areas, along roads and around main cities; mixed Manilkara (Sapotaceae) forest covers a huge area in the southern Central African Republic and in the northern Republic of Congo; and monodominant Gilbertiodendron (Fabaceae) forest is sparsely distributed along
rivers. The contrasted structure, composition, and functioning of the forest types imply pronounced differences in population and ecosystem processes, and call for adapted management and conservation strategies.
Fayolle, Adeline ; Université de Liège - ULiège > Forêts, Nature et Paysage > Gestion des ressources forestières et des milieux naturels
Picard, Nicolas; CIRAD, UPR BSEF, FRANCE > Biens et Services des Ecosystèmes Forestiers Tropicaux
Doucet, Jean-Louis ; Université de Liège - ULiège > Forêts, Nature et Paysage > Laboratoire de Foresterie des régions trop. et subtropicales
Swaine, Michael; University of Aberdeen, United Kingdom > Institute of Biological and Environmental Sciences
Bayol, Nicolas; Forest Ressources Management, Espaces Frejorgues, France
Bénédet, Fabrice; CIRAD, UPR BSEF, FRANCE > Biens et Services des Ecosystèmes Forestiers Tropicaux
Gourlet-Fleury, Sylvie; CIRAD, UPR BSEF, FRANCE > Biens et Services des Ecosystèmes Forestiers Tropicaux
Language :
English
Title :
A new insight in the structure, composition and functioning of central African moist forests
Publication date :
2014
Journal title :
Forest Ecology and Management
ISSN :
0378-1127
eISSN :
1872-7042
Publisher :
Elsevier Science
Issue :
329
Pages :
195-205
Peer reviewed :
Peer Reviewed verified by ORBi
Name of the research project :
ErA Net BiodivERsA CoForChange project (http://www.coforchange.fr)
Funders :
ANR - Agence Nationale de la Recherche NERC - Natural Environment Research Council
Commentary :
This study is part of the ErA Net BiodivERsA CoForChange project (http://www.coforchange.fr), funded by the National Research Agency (ANR) - France and the Natural Environment Research Council (NERC) - United Kingdom, involving 15 European, African and international partners. We wish to thank the timber companies:
Alpicam, Bois et Placages de Lopola, Danzer, Congolaise Industriale des Bois, Industries Forestieres de Batalimo, Likouala Timber, Mokabi SA. and Vicwood. The consulting firm Foret Resource Management (FRM), facilitated contacts and exchange with several logging companies, participated in data collection and data compiling, and provided inventory data files. A.F. was supported by ANR funding.
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