Catalogue en ligne

Miremby en ligne

A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar / David Obura

Public
ISBD

Titre :	A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar
Type de document :	texte imprimé
Auteurs :	David Obura, Auteur ; Ando Rabearisoa, Auteur ; Thomas Oliver, Auteur
Editeur :	Airlington [USA] : Conservation International
Année de publication :	2011
Importance :	100 p.
ISBN/ISSN/EAN :	978-1-934151-46-4
Langues :	Français (fre)
Catégories :	SCIENCES DE LA MER
Numéro du document :	A 10359/MAR 22
Niveau Bibliographique :	2
Bull1 (Theme principale) :	GESTION DE L'ENVIRONNEMENT MARIN
Bull2 (Theme secondaire) :	GESTION DES RESSOURCES MARINES

Est accompagné de

Corals of northeast Madagascar / David Obura

Accompagne A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar / David Obura

Titre :	Corals of northeast Madagascar
Type de document :	texte imprimé
Auteurs :	David Obura, Auteur
Editeur :	Conservation International
Année de publication :	2011
Importance :	p 17-28
Langues :	Anglais (eng)
Catégories :	SCIENCES DE LA MER
Mots-clés :	CORAIL MADAGASCAR GENETIQUE DES CORAUX ETUDE DES CORAUX
Résumé :	Northeast and Northwest Madagascar have similar levels of coral diversity, the highest recorded in the Western Indian Ocean. This survey recorded 281 species of corals, with lower taxonomic effort than earlier surveys that recorded 323 species of corals in Northwest Madagascar. At a regional scale, this coral diversity is equivalent to sites in N Mozambique and S Tanzania, defining a triangle of maximum diversity in the western Indian Ocean, encompassing the northern Mozambique channel. Sites in Northeast Madagascar host some of the largest populations of the most evolutionarily distinct and ecologically rare monospecific genera in the Indian Ocean, including Craterastrea laevis, Anomastrea irregularis, Horastrea indica and Gyromsilia interrupta. Significant range extensions of Indonesian species are reported in this survey, of Anacropora pillai and Turbinaria irregularis (previously recorded in Northwest Madagascar). A recently described rare species , Psammocora albopicta was found here, as well as a potentially undescribed species of Echinopora. Two of the five locations, Ambodivahibe and Loky Bay, have the highest level of diversity among the locations surveyed due to their depth and structural complexity, so have the highest value for habitat and species conservation. However individual sites in all 5 locations were important for some of the above key species, suggesting broad-based conservation.
Numéro du document :	A 10359/MAR 22
Niveau Bibliographique :	2
Bull1 (Theme principale) :	GESTION DE L'ENVIRONNEMENT MARIN
Bull2 (Theme secondaire) :	GESTION DES RESSOURCES MARINES

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Reef fishes of northeast Madagascar / Melita Samoilys

Accompagne A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar / David Obura

Titre :	Reef fishes of northeast Madagascar
Type de document :	texte imprimé
Auteurs :	Melita Samoilys, Auteur ; Bemahafaly Randriamanantsoa, Auteur
Editeur :	Conservation International
Année de publication :	2011
Importance :	p 29-39
Langues :	Anglais (eng)
Catégories :	SCIENCES DE LA MER
Mots-clés :	POISSONS DES CORAUX NORD OUEST DE MADAGASCAR TAXONOMIE
Résumé :	Comprehensive surveys and analyses of coral reef fish diversity are few in the Western Iindian Oocean (WIO), thus our understanding of patterns in reef fish diversity and species tichness across the WIO region is still poor. A region centred around southern Tanzania/northern Mozambique and Northern Madagascar has beeb proposed as a centre of coral diversity in the WIO, driven by the Indian Ocean current patterns (Obura 2008). It is likely that coral reef fishes follow similar gradient patterns and this hypothesis is currently under investigation by CORDIO EastAfrica’s Core region project : is there a WIO coral triangle ? funded by the Western Indian Ocean Marine Science Association. The northern tip of Madagascar represents a key location in this proposed centre of coral reef diversity with the first CI marine RAP in 2002 establishing the northwest tip of Madagascar as having the highest diversity of hard corals of any site in the Indian Ocean and over 750 reef-associated fish species . To date, only the northwestern side of Madagascar has been surveyed, therefore the current RAP set out to record species diversity in reef fishes on the far northeastern coastline of Madagascar. In contrast to fish diversity studies, many surveys and analyses of patterns in the population abundance of coral reef fishes across the WIO have been done, with a growing literature on the effects of fishing , the impacts of marine parks and reserves , and the effects of coral reef bleaching on reef fish communities and abundance. Certain trophic groups of reef fish , particularly the herbivores, have been shown to play critical role in coral reef resilience by controlling macro-algal communities and preventing coral-algal phase shifts. The IUCN Climate Change and Coral reefs working group has outlined protocols to quantify resistance and resilience indicators for coral reefs, including reef fishes which serve as useful indicators of reef health status and vulnerability. These attributes provided a second and separate focus of the RAP3 fish surveys : to collect data on the population abundance of selected reef fish taxa to compliment the coral and benthic reef resilience surveys, in order to assess the health of the coral reefs on this previously un-surveyed cost of northeastern Madagascar.
Numéro du document :	A 10359/MAR 22
Niveau Bibliographique :	2
Bull1 (Theme principale) :	GESTION DE L'ENVIRONNEMENT MARIN
Bull2 (Theme secondaire) :	GESTION DES RESSOURCES MARINES

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Echinoderms from the north-east coast of Madagascar / Jean Maharavo

Accompagne A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar / David Obura

Titre :	Echinoderms from the north-east coast of Madagascar
Type de document :	texte imprimé
Auteurs :	Jean Maharavo, Auteur
Editeur :	Conservation International
Année de publication :	2011
Importance :	p 40-43
Langues :	Anglais (eng)
Catégories :	SCIENCES DE LA MER
Mots-clés :	ECHINODERMES MADAGASCAR CONCOMBRE DE MER
Résumé :	This study was realized under the Rapid Assessment Program (Marine RAP) of marine biodiversity by Conservation International Madagascar. In total, 26 sites were surveyed over 20 days on the norheast coast of Madagascar from Ambodivahibe Bay to Vohemar. There are few publications or inventories of Echinoderms in Madagascar notably Cherbonnier. Only holothurians, which are extensively exploited for the preparation of trepang have been studied in detail. The main objectives of the study were to inventory the echinoderms of northeast Madagascar, then to test hypotheses about the ecological roles of echinoderms related coastal ecosystems and in particular the coral reef system and finally determine the existence or degree of overexploitation of sea cucumbers as one of the main fisheries in Madagascar.
Numéro du document :	A 10359/MAR 22
Niveau Bibliographique :	2
Bull1 (Theme principale) :	GESTION DE L'ENVIRONNEMENT MARIN
Bull2 (Theme secondaire) :	GESTION DES RESSOURCES MARINES

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Seagrasses and algae of north-eastern Madagascar / Monica Tombolahy

Accompagne A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar / David Obura

Titre :	Seagrasses and algae of north-eastern Madagascar
Type de document :	texte imprimé
Auteurs :	Monica Tombolahy, Auteur ; Giuseppe Di Carlo, Auteur
Editeur :	Conservation International
Année de publication :	2011
Importance :	p 44-52
Langues :	Anglais (eng)
Catégories :	SCIENCES DE LA MER
Mots-clés :	NORD EST DE MADAGASCAR ALGUES DE LA MER TAXONOMIE
Résumé :	The north-eastern coast of Madagascar presents extensive and highly diverse algal and seagrass assemblages. As this part of the coastline is almost completely undeveloped, these habitats are in a pristine state, only limited by environmental conditions, such as wave action, sediment runoff and nutrient concentrations. Ten species of seagrass were common, comparable to the species diversity found elsewhere in the Western Indian Ocean : Thalassodendron ciliatum, Thalassia hemprichii, Syringodium isoetifolium, Cymodocea rotundata C .serrulata, Halodule uninervis, H.wrightii, Halophila ovalis, H.stipulacea and Zostera capensis. Larger species were mainly found on stable substrates, mostly in coastal lagoons or on the shallow, inner edge of coral reef flats. In are where sendiment conditions were particularly dynamic and hydrodynamic forces play a major role, smaller, fast growing species were dominant, with considerable spatial and temporal variation. In the few urban areas present along this coastline, seagrass distribution was limited by pollution and eutrophication resulting from sewage outfalls and farming activities. To capture the diversity and abundance of algae and seagrass beds in the study area, four habitat categories are described here : coastal, including both exposed areas and lagoons ; reef flats ; riverine systems and deep/open water. The list of species, frequency of occurrence and shoot density are reported for each habitat, including key ecological processes such as sediment type, physical disturbance, light limitation and human-induced threats. The understanding of differences in the habitats, their key ecological functions and potential threats described here provide recommendations for managing algal beds and seagrass meadows and their ecosystem services.
Numéro du document :	A 10359/MAR 22
Niveau Bibliographique :	2
Bull1 (Theme principale) :	GESTION DE L'ENVIRONNEMENT MARIN
Bull2 (Theme secondaire) :	GESTION DES RESSOURCES MARINES

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Coral-associated exosymbionts of northeast Madagascar / Sea Mc Keon

Accompagne A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar / David Obura

Titre :	Coral-associated exosymbionts of northeast Madagascar
Type de document :	texte imprimé
Auteurs :	Sea Mc Keon, Auteur
Editeur :	Conservation International Madagascar
Année de publication :	2011
Importance :	p 53-55
Langues :	Anglais (eng)
Catégories :	SCIENCES DE LA MER
Mots-clés :	CORAIL EXOSYMBIONT NORD EST DE MADAGASCAR TAXONOMIE
Résumé :	Our best estimates of global biodiversity are poor and even getting within the correct order of magnitude has proven to be a difficult goal. Entomologists working in rainforests have provided the best working estimates of terrestrial diversity. Based on the correlation between structural species (trees) and host specific symbionts (herbivorous insects), they have estimated global insect abundance at 2-50 million species. Symbioses are ubiquitous on corral reefs, yet a similar approach has not been taken with regard to estimating the numbers of host-specific reef associates and the further extrapolation to estimates of reef diversity. This work will build up a working collection of marine structural species (hexacorals, octocorals, etc.) and their associated species (families of crabs, shrimp, barnacles, gastropods, bivalves, amphipods etc.) that in the future may contribute to deriving a total biodiversity estimate for the region.
Numéro du document :	A 10359/MAR 22
Niveau Bibliographique :	2
Bull1 (Theme principale) :	GESTION DE L'ENVIRONNEMENT MARIN
Bull2 (Theme secondaire) :	GESTION DES RESSOURCES MARINES

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Coral reef health and status / David Obura

Accompagne A rapid marine biodiversity assessment of the coral reefs of Northeast Madagascar / David Obura

Titre :	Coral reef health and status
Type de document :	texte imprimé
Auteurs :	David Obura, Auteur ; Tom Oliver, Auteur
Editeur :	Conservation International Madagascar
Année de publication :	2011
Importance :	p 56-67
Langues :	Anglais (eng)
Catégories :	SCIENCES DE LA MER
Mots-clés :	CORAIL DES ROCHERS MADAGASCAR ETUDE DES CORAUX
Résumé :	To prioritize resilient reefs for conservation action, we evaluated the sites surveyed in the Northeast Madagascar Marine RAP using resilience assessment methods developed by IUCN and CORDIO East Africa. Overall the region showed high coral over (mean of 48%) and coral populations that spanned the expected size range for the genus in question, including large, mature colonies. The common occurrence of large colonies suggests that there has been no catastrophic morality in the past few decades. Coral recruitment was present but relatively low. Even after an extended heating event that ended preceding the survey, coral bleaching was low, showing a mean -5% of colonies affected. This and the low impact detected from the 1998 mass bleaching event suggests that the corals in this region have largely resisted the negative effects of heating events and supports the hypothesis that those reefs are thermally resistant. In general, the northern three locations (Ambodivahibe, Nosy Ankao, Loky bay), showed greater coral cover, larger corals and fewer bleached colonies than the southern two sites (Andravina and Vohemar). Coral recruitment was highest on the northern and southern extremes in Ambodivahibe and Vohemar, though overall was comparatively low. The generally intact structure of the reefs and apparent resistance to coral bleaching suggests that the region is a priority for conservation. We recommand conservation actions to enhance coral recruitment, a key factor for ecological resilience, through the targeted restriction of of fishing pressure and watershed management to limit/reduce sedimentation.
Numéro du document :	A 10359/MAR 22
Niveau Bibliographique :	2
Bull1 (Theme principale) :	GESTION DE L'ENVIRONNEMENT MARIN
Bull2 (Theme secondaire) :	GESTION DES RESSOURCES MARINES

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Origine
33143	A 10359/MAR 22	Livre	Bibiotheque CIDST	Bibliotheque DDI	Exclu du prêt	Don

Miremby en ligne

Exemplaires

Exemplaires

Exemplaires

Exemplaires

Exemplaires

Exemplaires

Exemplaires (1)

Accueil

Sélection de la langue

Se connecter

Adresse