28 research outputs found
Local socio-economic effects of protected area conservation: The case of Maromizaha forest, Madagascar
The vision Madagascar Naturally aimed to triple the size of protected areas in Madagascar from 1.7 million hectares to 6 million hectares before 2008, in order to ensure the safe guarding of Madagascarâs natural heritage and the human well-being that depends on it. In 2008, Maromizaha forest was selected by the Ministry of Environment and Forests tobecome a New Protected Area where the delegated manager is the Groupe dâEtude et de Recherche sur les Primates de Madagascar (GERP). One of GERPâs strategies is to provide support to the livelihoods of the local people around the Maromizaha protected area in order to reduce the dependency on natural resources. During April 2014, GERP organized a rapid socio-economic survey of 70 households across six villages, in order to make a preliminary, comparison and assessment of this development support and its impact on the main income generating activities of the local people, their highest level of formal education in 2008 and 2014, and their thinking about conservation offsetting. The results showed that in 2014, 70% of local people were engaged in agriculture and less than 40% in cattle farming. Some villagers have benefited from pilot development projects organized by financial and environmental organizations. Other local people benefited from other livelihood activities related to the conservation management of the forest. Most participants were aware of the ecosystem services of the forests (94.3%) and the education level has increased from 2008 to 2014, although even in 2014, 56% of the survey participants were educated only to primary school level; the rate of illiteracy is at 15.6%. We summarize some strengths, weaknesses and recommendations in order to improve the management of the Maromizaha Protected Area
The Importance of Protein in Leaf Selection of Folivorous Primates
Protein limitation has been considered a key factor in hypotheses on the evolution of life history and animal communities, suggesting that animals should prioritize protein in their food choice. This contrasts with the limited support that food selection studies have provided for such a priority in nonhuman primates, particularly for folivores. Here, we suggest that this discrepancy can be resolved if folivores only need to select for high protein leaves when average protein concentration in the habitat is low. To test the prediction, we applied meta-analyses to analyze published and unpublished results of food selection for protein and fiber concentrations from 24 studies (some with multiple species) of folivorous primates. To counter potential methodological flaws, we differentiated between methods analyzing total nitrogen and soluble protein concentrations. We used a meta-analysis to test for the effect of protein on food selection by primates and found a significant effect of soluble protein concentrations, but a non-significant effect for total nitrogen. Furthermore, selection for soluble protein was reinforced in forests where protein was less available. Selection for low fiber content was significant but unrelated to the fiber concentrations in representative leaf samples of a given forest. There was no relationship (either negative or positive) between the concentration of protein and fiber in the food or in representative samples of leaves. Overall our study suggests that protein selection is influenced by the protein availability in the environment, explaining the sometimes contradictory results in previous studies on protein selectio
Geochemical signatures of stream sediments within the main geological domains and terranes of North and Central Madagascar
Geochemical mapping of North and Central Madagascar was carried out using stream sediments at an average density of one sample per 11 km2. Over 50 elements were determined from some 13,300 stream sediments using a sample size fraction of <150 ÎŒm following hot aqua regia digestion. Partially extractable concentrations of six major elements and seven base metals reveal that the Andriamena `greenstone' Belt of the Tsaratanana Complex is geochemically distinct from the other geological divisions within the Precambrian basement of central and northern Madagascar. In particular, this study has shown the detailed spatial distribution of anomalous concentrations of base metals which confirm known areas of chromite mineralisation within the Andriamena Belt. Base metal anomalies also occur in relation to Cretaceous and Neogene volcanic rocks, for example at Nosy Be, and mafic-ultramafic intrusions such as along the Maroala deformation zone. The distribution of anomalous Au in stream sediments showed good correspondence with known gold districts of central and northern Madagascar. Highest concentrations were measured in stream sediments from within the Ampasary-Mananjary (southern Androna-Mandritsara) and Andavakoera (northern margin of North Bemarivo) gold districts. The results of the stream sediment geochemistry show that these new data provide valuable information for current and future mineral exploration and environmental studies in Madagascar, at both regional and local scale
Polyphase Neoproterozoic orogenesis within the East Africa-Antarctica Orogenic Belt in central and northern Madagascar
Our recent geological survey of the basement of central and northern Madagascar
allowed us to re-evaluate the evolution of this part of the East AfricaâAntarctica Orogen
(EAAO). Five crustal domains are recognized, characterized by distinctive lithologies and histories
of sedimentation, magmatism, deformation and metamorphism, and separated by tectonic and/or
unconformable contacts. Four consist largely of Archaean metamorphic rocks (Antongil, Masora
and Antananarivo Cratons, Tsaratanana Complex). The fifth (Bemarivo Belt) comprises Proterozoic
meta-igneous rocks. The older rocks were intruded by plutonic suites at c. 1000 Ma, 820â
760 Ma, 630â595 Ma and 560â520 Ma. The evolution of the four Archaean domains and their
boundaries remains contentious, with two end-member interpretations evaluated: (1) all five
crustal domains are separate tectonic elements, juxtaposed along Neoproterozoic sutures and (2)
the four Archaean domains are segments of an older Archaean craton, which was sutured
against the Bemarivo Belt in the Neoproterozoic. Rodinia fragmented during the early Neoproterozoic
with intracratonic rifts that sometimes developed into oceanic basins. Subsequent Mid-
Neoproterozoic collision of smaller cratonic blocks was followed by renewed extension and
magmatism. The global âTerminal Pan-Africanâ event (560â490 Ma) finally stitched together
the Mid-Neoproterozoic cratons to form Gondwana
Neoproterozoic extension in the greater dharwar craton: A reevaluation of the "betsimisaraka suture" in madagascarn
The Precambrian shield of Madagascar is reevaluated with recently compiled geological data and new U-Pb sensitive high-resolution ion microprobe (SHRIMP) geochronology. Two Archean domains are recognized: the eastern Antongil-Masora domain and the central Antananarivo domain, the latter with distinctive belts of metamafic gneiss and schist (Tsaratanana Complex). In the eastern domain, the period of early crust formation is extended to the Paleo-Mesoarchean (3.32-3.15 Ga) and a supracrustal sequence (Fenerivo Group), deposited at 3.18 Ga and metamorphosed at 2.55 Ga, is identified. In the central domain, a Neoarchean period of high-grade metamorphism and anatexis that affected both felsic (Betsiboka Suite) and mafic gneisses (Tsaratanana Complex) is documented. We propose, therefore, that the Antananarivo domain was amalgamated within the Greater Dharwar Craton (India + Madagascar) by a Neoarchean accretion event (2.55-2.48 Ga), involving emplacement of juvenile igneous rocks, high-grade metamorphism, and the juxtaposition of disparate belts of mafic gneiss and schist (metagreenstones). The concept of the "Betsimisaraka suture" is dispelled and the zone is redefined as a domain of Neoproterozoic metasedimentary (Manampotsy Group) and metaigneous rocks (Itsindro-Imorona Suite) formed during a period of continental extension and intrusive igneous activity between 840 and 760 Ma. Younger orogenic convergence (560-520 Ma) resulted in east-directed overthrusting throughout south Madagascar and steepening with local inversion of the domain in central Madagascar. Along part of its length, the Manampotsy Group covers the boundary between the eastern and central Archean domains and is overprinted by the Angavo-Ifanadiana high-strain zone that served as a zone of crustal weakness throughout Cretaceous to Recent times
A new geological framework for south-central Madagascar, and its relevance to the "out-of-Africa" hypothesis
The Precambrian shield of south-central Madagascar, excluding the Vohibory region, consists of three geologic domains, from north to south: Antananarivo, Ikalamavony-Itremo, and Anosyen-Androyen. The northern Antananarivo domain represents the Neoarchea