Données préliminaires sur l’exploitation des pangolins (Pholidota) autour du Parc National de Kahuzi-Biega, République Démocratique du Congo

Dans un contexte où la demande des écailles des pangolins pour la médicine traditionnelle chinoise ne cesse d’augmenter, ces animaux se trouvent de plus à plus braconner. Il est donc important que les études soient menées dans leur zone de répartition pour arriver à dégager les motivations de cette exploitation dans chaque zone. C’est dans cet angle que l’étude sur l’exploitation des pangolins et de leurs produits dérivés a été réalisée autour du parc national de Kahuzi-Biega avec pour objectif de dégager les différentes fins pour lesquelles ces animaux y sont exploités et identifier les différents acteurs intervenant dans ce domaine via l’information et les connaissances des riverains. La méthode d’enquête individuelle et collective a été conduite auprès de 116 personnes pendant une période de deux mois (mars et avril 2019) autour du Secteur Tshivanga et du Secteur Itebero. Les analyses comparatives, Khi-deux, Ficher et les analyses à correspondances multiples (ACM) ont été effectuées à l’aide du logiciel Past 3.2. Les résultats obtenus montrent que les pangolins sont principalement exploités pour l’alimentation et la médecine traditionnelles. Cependant, le trafic de leurs écailles a fait augmenter la demande dans la zone. Les demandeurs des écailles viennent principalement des grandes villes (Bukavu, Goma, Kisangani) et des certaines pays étrangers (Ouganda, Burundi, Tanzanie et les agents de la Mission des Nations-Unies pour la Stabilisation au Congo). Le commerce des écailles pour satisfaire la demande externe, bien qu’encore à ces débuts, vient menacer les pangolins dans cette zone où la chasse est strictement interdite. Ce commerce passe par des intermédiaires, dont les principaux sont les enfants du milieu.Mots clés : Étude préliminaire, exploitation, pangolins, Kahuzi-biega, RDC English Title: Preliminary data on the exploitation of Pangolins (Pholidota) about the National Park of Kahuzi-Biega, Democratic Republic of Congo (DRC)In a context where the demand for pangolin scales for traditional Chinese medicine continues to increase, these animals are increasingly being poached. It is therefore important that studies be carried out in their area of distribution in order to identify the motivations for this exploitation in each area. It is in this perspective that the study on the exploitation of pangolins and their by-products was carried out around the Kahuzi-Biega National Park with the aim of identifying the different purposes for which these animals are exploited there and to identify the different actors involved in this field through the information and knowledge of local residents. The individual and collective survey method was conducted among 116 people over a two-month period (March and April 2019) around the Tshivanga Sector and the Itebero Sector. Comparative, Chi-square, File and Multiple Correspondence Analysis (MCA) analyses were carried out using Past 3.2 software. The results obtained show that pangolins are mainly exploited for traditional food and medicine. However, the trafficking of their scales has increased demand in the area. The demand for the scales comes mainly from the big cities (Bukavu, Goma, Kisangani) and from some foreign countries (Uganda, Burundi, Tanzania and agents of the United Nations Stabilization Mission in Congo). The trade in scales to satisfy external demand, although still in its infancy, is threatening pangolins in this area where hunting is strictly prohibited. This trade goes through intermediaries, the main ones being local children.Keywords: Preliminary study, exploitation, pangolins, Kahuzi-biega, DRC

Resistance of African tropical forests to an extreme climate anomaly.

The responses of tropical forests to environmental change are critical uncertainties in predicting the future impacts of climate change. The positive phase of the 2015-2016 El Niño Southern Oscillation resulted in unprecedented heat and low precipitation in the tropics with substantial impacts on the global carbon cycle. The role of African tropical forests is uncertain as their responses to short-term drought and temperature anomalies have yet to be determined using on-the-ground measurements. African tropical forests may be particularly sensitive because they exist in relatively dry conditions compared with Amazonian or Asian forests, or they may be more resistant because of an abundance of drought-adapted species. Here, we report responses of structurally intact old-growth lowland tropical forests inventoried within the African Tropical Rainforest Observatory Network (AfriTRON). We use 100 long-term inventory plots from six countries each measured at least twice prior to and once following the 2015-2016 El Niño event. These plots experienced the highest temperatures and driest conditions on record. The record temperature did not significantly reduce carbon gains from tree growth or significantly increase carbon losses from tree mortality, but the record drought did significantly decrease net carbon uptake. Overall, the long-term biomass increase of these forests was reduced due to the El Niño event, but these plots remained a live biomass carbon sink (0.51 ± 0.40 Mg C ha-1 y-1) despite extreme environmental conditions. Our analyses, while limited to African tropical forests, suggest they may be more resistant to climatic extremes than Amazonian and Asian forests

Resistance of African tropical forests to an extreme climate anomaly

The responses of tropical forests to environmental change are critical uncertainties in predicting the future impacts of climate change. The positive phase of the 2015–2016 El Niño Southern Oscillation resulted in unprecedented heat and low precipitation in the tropics with substantial impacts on the global carbon cycle. The role of African tropical forests is uncertain as their responses to short-term drought and temperature anomalies have yet to be determined using on-the-ground measurements. African tropical forests may be particularly sensitive because they exist in relatively dry conditions compared with Amazonian or Asian forests, or they may be more resistant because of an abundance of drought-adapted species. Here, we report responses of structurally intact old-growth lowland tropical forests inventoried within the African Tropical Rainforest Observatory Network (AfriTRON). We use 100 long-term inventory plots from six countries each measured at least twice prior to and once following the 2015–2016 El Niño event. These plots experienced the highest temperatures and driest conditions on record. The record temperature did not significantly reduce carbon gains from tree growth or significantly increase carbon losses from tree mortality, but the record drought did significantly decrease net carbon uptake. Overall, the long-term biomass increase of these forests was reduced due to the El Niño event, but these plots remained a live biomass carbon sink (0.51 ± 0.40 Mg C ha−1 y−1) despite extreme environmental conditions. Our analyses, while limited to African tropical forests, suggest they may be more resistant to climatic extremes than Amazonian and Asian forests

A new hero emerges: another exceptional mammalian spine and its potential adaptive significance

The hero shrew's (Scutisorex somereni) massive interlocking lumbar vertebrae represent the most extreme modification of the vertebral column known in mammals. No intermediate form of this remarkable morphology is known, nor is there any convincing theory to explain its functional significance. We document a new species in the heretofore monotypic genus Scutisorex; the new species possesses cranial and vertebral features representing intermediate character states between S. somereni and other shrews. Phylogenetic analyses of DNA sequences support a sister relationship between the new species and S. somereni. While the function of the unusual spine in Scutisorex is unknown, it gives these small animals incredible vertebral strength. Based on field observations, we hypothesize that the unique vertebral column is an adaptation allowing these shrews to lever heavy or compressive objects to access concentrated food resources inaccessible to other animals

The persistence of carbon in the African forest understory

Quantifying carbon dynamics in forests is critical for understanding their role in long-term climate regulation1,2,3,4. Yet little is known about tree longevity in tropical forests3,5,6,7,8, a factor that is vital for estimating carbon persistence3,4. Here we calculate mean carbon age (the period that carbon is fixed in trees7) in different strata of African tropical forests using (1) growth-ring records with a unique timestamp accurately demarcating 66 years of growth in one site and (2) measurements of diameter increments from the African Tropical Rainforest Observation Network (23 sites). We find that in spite of their much smaller size, in understory trees mean carbon age (74 years) is greater than in sub-canopy (54 years) and canopy (57 years) trees and similar to carbon age in emergent trees (66 years). The remarkable carbon longevity in the understory results from slow and aperiodic growth as an adaptation to limited resource availability9,10,11. Our analysis also reveals that while the understory represents a small share (11%) of the carbon stock12,13, it contributes disproportionally to the forest carbon sink (20%). We conclude that accounting for the diversity of carbon age and carbon sequestration among different forest strata is critical for effective conservation management14,15,16 and for accurate modelling of carbon cycling4

Asynchronous carbon sink saturation in African and Amazonian tropical forests

Structurally intact tropical forests sequestered about half of the global terrestrial carbon uptake over the 1990s and early 2000s, removing about 15 per cent of anthropogenic carbon dioxide emissions. Climate-driven vegetation models typically predict that this tropical forest ‘carbon sink’ will continue for decades. Here we assess trends in the carbon sink using 244 structurally intact African tropical forests spanning 11 countries, compare them with 321 published plots from Amazonia and investigate the underlying drivers of the trends. The carbon sink in live aboveground biomass in intact African tropical forests has been stable for the three decades to 2015, at 0.66 tonnes of carbon per hectare per year (95 per cent confidence interval 0.53–0.79), in contrast to the long-term decline in Amazonian forests. Therefore the carbon sink responses of Earth’s two largest expanses of tropical forest have diverged. The difference is largely driven by carbon losses from tree mortality, with no detectable multi-decadal trend in Africa and a long-term increase in Amazonia. Both continents show increasing tree growth, consistent with the expected net effect of rising atmospheric carbon dioxide and air temperature. Despite the past stability of the African carbon sink, our most intensively monitored plots suggest a post-2010 increase in carbon losses, delayed compared to Amazonia, indicating asynchronous carbon sink saturation on the two continents. A statistical model including carbon dioxide, temperature, drought and forest dynamics accounts for the observed trends and indicates a long-term future decline in the African sink, whereas the Amazonian sink continues to weaken rapidly. Overall, the uptake of carbon into Earth’s intact tropical forests peaked in the 1990s. Given that the global terrestrial carbon sink is increasing in size, independent observations indicating greater recent carbon uptake into the Northern Hemisphere landmass reinforce our conclusion that the intact tropical forest carbon sink has already peaked. This saturation and ongoing decline of the tropical forest carbon sink has consequences for policies intended to stabilize Earth’s climate

Plot Data from "Diversity and carbon storage across the tropical forest biome."

Tropical forests are global centres of both biodiversity and carbon storage. Many tropical countries aspire to protect forest to fulfil biodiversity and climate mitigation policy targets, but the conservation strategies needed to achieve these two functions depend critically on the tropical forest diversity-carbon relationship and this remains largely unexplored. Attempts to assess and understand this relationship in tropical forest ecosystems have been hindered by the scarcity of inventories where carbon storage in aboveground biomass and species identifications have been simultaneously and robustly quantified. Here, we compile a unique pan-tropical dataset of 360 plots located in old-growth closed-canopy forest, surveyed using standardised methods, allowing a multi-scale evaluation of the relationship between carbon storage and tree diversity. We find strongly contrasting variation in diversity and carbon among continents. Thus, on average, African forests have high carbon storage but relatively low diversity, Amazonian forests have high diversity but less carbon, and Southeast Asian forests have both high diversity and high carbon storage. Carbon-diversity relationships among all plots across the tropics are absent, and within continents are either weak (Asia) or absent (Amazonia, Africa). Within 1 ha plots a weak positive relationship is detectable, indicating that diversity effects in tropical forests may be scale dependent. The absence of clear diversity-carbon relationships at scales relevant to most conservation planning means that carbon-centred conservation strategies alone would miss many high diversity ecosystems. As tropical forests can have any combination of tree diversity and carbon stocks both will require explicit consideration when optimising policies to manage tropical carbon and biodiversity