Environmental Impacts of the Oil Palm Cultivation in Cameroon

Since 1990, oil palm cultivation, because nibbling large zones in dense forest areas of Cameroon, becomes the main driver of deforestation. It leads to the loss of plant and animal biodiversity as well as engaging soils and water pollution, which raises questions about its sustainability. Nowadays, palm plantations occupy almost 400 000 ha shared between agro-industries, elites and small farmers while annual palm oil production increased from 150, 000 tons in 2000 to 413,000 tons in 2018 against a demand that peaked at 1.179 million tons in 2018. This would assess the impacts of the oil palm exploitation in Cameroon. The objective of this article is to analyze the four dimensions of impacts closely linked to sustainability dimensions (ecological, sociocultural, economical and institutional) dimensions of sustainability of the oil palm sector in Cameroon. The approach is based on field surveys carried out in various production basins, particularly in the South-West, Littoral and Central regions. They also take into account the resolutions of various workshops bringing together stakeholders on the matter of sustainability in the oil palm sector in Cameroon. Satellite images were also used to map the spatial evolution of oil palm in the production basins. The result is a boom and a considerable expansion of the oil palm to which we can note a lack of adequate policy due to the constraints and hesitations of the Cameroonian administrations. Such a situation requires a better articulation of the tensions between development and environmental issues in Cameroon

Quantitative estimates of glacial refugia for chimpanzees (Pan troglodytes) since the Last Interglacial (120,000 BP).

Paleoclimate reconstructions have enhanced our understanding of how past climates have shaped present-day biodiversity. We hypothesize that the geographic extent of Pleistocene forest refugia and suitable habitat fluctuated significantly in time during the late Quaternary for chimpanzees (Pan troglodytes). Using bioclimatic variables representing monthly temperature and precipitation estimates, past human population density data, and an extensive database of georeferenced presence points, we built a model of changing habitat suitability for chimpanzees at fine spatio-temporal scales dating back to the Last Interglacial (120,000 BP). Our models cover a spatial resolution of 0.0467° (approximately 5.19 km2 grid cells) and a temporal resolution of between 1000 and 4000 years. Using our model, we mapped habitat stability over time using three approaches, comparing our modeled stability estimates to existing knowledge of Afrotropical refugia, as well as contemporary patterns of major keystone tropical food resources used by chimpanzees, figs (Moraceae), and palms (Arecacae). Results show habitat stability congruent with known glacial refugia across Africa, suggesting their extents may have been underestimated for chimpanzees, with potentially up to approximately 60,000 km2 of previously unrecognized glacial refugia. The refugia we highlight coincide with higher species richness for figs and palms. Our results provide spatio-temporally explicit insights into the role of refugia across the chimpanzee range, forming the empirical foundation for developing and testing hypotheses about behavioral, ecological, and genetic diversity with additional data. This methodology can be applied to other species and geographic areas when sufficient data are available

Conservation and development: the influence of accessibility, participatory management and immigration around the Bénoué

This article evaluates the state of conservation and development of the landscape of Bénoué National Park and its surroundings in Northern Cameroon. Thirty indicators classified into five "capital asset" groups were the object of a participatory judgment between 2nd and 13th May 2006, by 13 local communities living in the hunting areas around the park. The mode of evaluation based on the scales of value going from 1 (worst situation) to 5 (optimal situation) was used. The data collected were presented in a spider web diagram to show the weak and strong points of each category of asset: natural, social, human, physical and financial, on the assumption that the different categories of assets are exchangeable. The overall results of the landscape show that local stakeholders perceive the natural asset as being weaker compared to other categories of assets. The national road that passes through the network of protected area and links the two big towns of Garoua and Ngaoundere, the immigration, the mode of involvement of the population in the management of natural resources are the main factors which affect the landscape. It is necessary to think of the best way to reconcile the conservation interests with those of development through the development of scenarios to stimulate communication between stakeholders in the landscape and national and international decision makers. The internalization of the conservation of biodiversity within communities and decentralized municipalities benefiting partly from land lease taxes is yet to be promoted. It is the same for the development of synergies between the ministry responsible for wildlife and protected areas and other departments that influence the management of natural resources

Conservation and development: the influence of accessibility,\ud participatory management and immigration around the Bénoué

This article evaluates the state of conservation and development of the landscape of Bénoué National Park and its\ud surroundings in Northern Cameroon. Thirty indicators classified into five "capital asset" groups were the object of a participatory judgment between 2nd and 13th May 2006, by 13 local communities living in the hunting areas\ud around the park. The mode of evaluation based on the scales of value going from 1 (worst situation) to 5 (optimal\ud situation) was used. The data collected were presented in a spider web diagram to show the weak and strong points\ud of each category of asset: natural, social, human, physical and financial, on the assumption that the different\ud categories of assets are exchangeable. The overall results of the landscape show that local stakeholders perceive\ud the natural asset as being weaker compared to other categories of assets. The national road that passes through the network of protected area and links the two big towns of Garoua and Ngaoundere, the immigration, the mode of\ud involvement of the population in the management of natural resources are the main factors which affect the\ud landscape. It is necessary to think of the best way to reconcile the conservation interests with those of development through the development of scenarios to stimulate communication between stakeholders in the landscape and national and international decision makers. The internalization of the conservation of biodiversity within communities and decentralized municipalities benefiting partly from land lease taxes is yet to be promoted. It is the same for the development of synergies between the ministry responsible for wildlife and protected areas and other departments that influence the management of natural resources

REDD payments as incentive for reducing forest loss

Strategies for reducing emissions from deforestation and forest degradation (REDD) could become an important part of a new agreement for climate change mitigation under the United Nations Framework Convention on Climate Change. We constructed a system dynamics model for a cocoa agroforest landscape in southwestern Ghana to explore whether REDD payments are likely to promote forest conservation and what socio-economic implications would be. Scenarios were constructed for business as usual (cocoa production at the expense of forest), for payments for avoided deforestation of old-growth forest only and for payments for avoided deforestation of all forests, including degraded forest. The results indicate that in the short term, REDD is likely to be preferred by farmers when the policy focuses on payments that halt the destruction of old-growth forests only. However, there is the risk that REDD contracts may be abandoned in the short term. The likeliness of farmers to opt for REDD is much lower when also avoiding deforestation of degraded forest since this land is needed for the expansion of cocoa production. Given that it is mainly the wealthier households that control the remaining forest outside the reserves, REDD payments may increase community differentiation, with negative consequences for REDD policies. (Résumé d'auteur

Influence of tourism activities and PA size on threat level in 83 PAs.

<p>In bold are highlighted significant values (p <i><0.05</i>). See abbreviations in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114154#pone-0114154-t002" target="_blank">Tab 2</a>. AIC, Akaike's Information Criterion; AICw, Akaike Information Criterion weight; Rank, model rank from the smallest to the largest AIC value; k, number of variables including the intercept.</p><p>Influence of tourism activities and PA size on threat level in 83 PAs.</p

Proportion of protected areas with conservation activities between 1990 and 1999 across different African regions.

<p>The number of protected areas with available information on presence and absence of any conservation activity (research, tourism and law enforcement guards) over the considered period were in total 105.</p

Regional distribution of the protected areas (PAs) in tropical Africa considered in the analyses.

<p>The regions are coloured in different grey scale colours. Light grey represents West Africa, including 54 protected areas; medium grey represents Central Africa, including 31 protected areas; dark grey represents East Africa, including 14 protected areas. On the left-side bottom corner a MODIS NDVI image of Africa, with a red quadrant highlighting the tropical area considered in the study.</p

Influence of law enforcement activities and PA size on threat levels in 90 PAs.

<p>In bold are highlighted significant values (p <i><0.05</i>). See abbreviations in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114154#pone-0114154-t002" target="_blank">Tab 2</a>. AIC, Akaike's Information Criterion; AICw, Akaike Information Criterion weight; Rank, model rank from the smallest to the largest AIC value; k, number of variables including the intercept.</p><p>Influence of law enforcement activities and PA size on threat levels in 90 PAs.</p

Influence of research activities and PA size on threat level in 92 PAs.

<p>In bold are highlighted significant values (p <i><0.05</i>). See abbreviations in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114154#pone-0114154-t002" target="_blank">Tab 2</a>. AIC, Akaike's Information Criterion; AICw, Akaike Information Criterion weight; Rank, model rank from the smallest to the largest AIC value; k, number of variables including the intercept.</p><p>Influence of research activities and PA size on threat level in 92 PAs.</p