Academic literature on the topic 'Upper Guinean Forests'

Amietophrynus superciliaris is known to occur in rain forests from West Africa to eastern Democratic Republic of Congo and Gabon. We herein present morphological and molecular data indicating the existence of three distinct taxa. The name A. superciliaris superciliaris is restricted to toads from the western Lower Guinean Forest (eastern Nigeria, Cameroon, Equatorial Guinea, Gabon). We resurrect A. s. chevalieri for the Upper Guinean forest (Sierra Leone, Guinea, Liberia, Ivory Coast, Ghana) and describe a new species occurring in the eastern part of the Lower Guinean Forest (eastern Democratic Republic of Congo). Amietophrynus channingi sp. nov. from eastern Lower Guinean Forest differs from both other taxa by its brownish lateral coloration (reddish-purple in the other taxa). The new species differs morphologically from western Lower Guinean A. s. superciliaris by a less pointed eyelid process, a dark coloured posterior abdominal region and a dark coloured vertebral line (both absent in A. s. superciliaris), the shape of the parotid glands (bulged and rounded at the posterior tip in the new species, slender drop shaped and pointed at the posterior tip in A. s. superciliaris), and juvenile interorbital markings (V-shaped in the new species, usually interrupted and broken in A. s. superciliaris). Amietophrynus channingi sp. nov. differs from the Upper Guinean A. s. chevalieri by the presence of an eyelid process (absent in A. s. chevalieri), presence of a dark vertebral line and a pair of dark spots on the posterior part of the back (both absent in A. s. chevalieri). The Upper Guinean A. s. chevalieri differs from western Lower Guinean A. s. superciliaris by the absence of an eyelid process, a dark coloured posterior abdominal region (absent in A. s. superciliaris) and lacking a pair of dark spots in the posterior part of the back (present in A. s. superciliaris). The new species differs from both other taxa by 2.2–2.8% in the investigated 16S rRNA gene. West African and western Central African populations differ by only 0.9–1.1% in 16S rRNA, lacking any intra-taxon variation within each clade, and are cautiously regarded as subspecies although the genetic distinction is mirrored by strong morphological differences and distinct geographic distribution which may support its elevation to species status once that more comprehensive data become available. A key to the taxa of the A. superciliaris-species complex is provided.

Elephant populations have declined greatly in the rain forests of Upper Guinea (Africa, west of the Dahomey Gap). Elephants have a number of well-known influences on vegetation, both detrimental and beneficial to trees. They are dispersers of a large number of woody forest species, giving rise to concerns that without elephants the plant diversity of Upper Guinean forest plant communities will not be maintained. This prospect was examined with respect to four sources of inventory and research data from Ghana, covering nearly all (more than 2000) species of forest plant. Evidence supporting the hypothesis that plant populations are collapsing without elephants is conspicuously absent in these datasets, although Balanites wilsoniana is likely to suffer dramatically on a centennial scale in the absence of forest elephants. A few other species are likely to decline, although at an even slower rate. In the context of other processes current in these forests, loss of elephants is an insignificant concern for plant biodiversity. Elephant damage of forests can be very significant in Africa, but loss of this influence is more than compensated for by human disturbance. Elephants have played a significant part in the shaping of West African rain forest vegetation. However, it is the conservation of elephants that should be of primary concern. Tree populations should be managed to promote them, rather than vice versa.

The distribution of the White-Lipped Frog Amnirana albolabris was long assumed to extend from eastern-central to western African rainforests. However, recent molecular phylogenetic analyses revealed that this taxon likely represents several undescribed species. Because the name-bearing types were collected in Gabon, the distantly related West African populations clearly represent an undescribed species that partly occurs in sympatry with Amnirana fonensis. Based on an integrative taxonomic approach, including molecular, morphological, and acoustic data, we describe the ‘albolabris’ populations from the Upper Guinean Forest Zone as a new species, and redescribe the morphologically similar A. fonensis on the bases of a larger series of genotyped individuals, including the first known females. We also provide new biological information for A. fonensis, including their advertisement call, habitat, and reproductive data. The new species is sister to A. fonensis and the two species differ by 5.8% in the mitochondrial 16S ribosomal RNA gene. Morphologically, males of the new species are smaller and have relatively smaller humeral glands. Females of the new species seem to have shorter legs than A. fonensis. In comparison to A. fonensis, the advertisement call of the new species has a higher dominant frequency and more pronounced frequency modulation. The two species differ in their distribution and habitat preferences, as revealed by environmental niche modelling. Whereas the new species is restricted to the Upper Guinean forests and thus is a true lowland-rainforest inhabitant, A. fonensis lives predominantly in Guinean montane forests in the forest-savanna mosaic zone. 

“The Dahomey Gap” is a human-derived mostly savannah region that separates the Guineo-Congolian rainforest block into two major units: the Upper Guinean and the Lower Guinean Forest blocks. Several forest patches are distributed throughout this savannah-dominated habitat. The mammal communities in the Dahomey Gap region have been poorly studied. In this paper we analyse the species richness and abundance of, as well as conservation implications for, medium and large mammals (especially ungulates) inhabiting a complex of flooded forests near the Mono river in south-eastern Togo. We use several field methods to describe the species richness of mammals in this area, including camera-trapping, recce transects, Kilometric Index of Abundance (KIA) estimates, examination of hunters’ catches and face-to-face hunter interviews. Overall, we directly recorded 19 species that coexist in these forests. Based on interviews, nine other species were confirmed as present in the study area. Only five species were common: Cephalophus rufilatus, Tragelaphus scriptus, Chlorocebus aethiops, Atilax paludinosus and Herpestes ichneumon. The area still contains various threatened species such as Tragelaphus spekii and Hippopotamus amphibius. We stress that to ensure the protection of the Dahomey Gap mammals, it is important to seriously consider protecting not only the forest patches but also the surroundings, mainly savannah landscapes.

Sierra Leone is situated at the western edge of the Upper Guinean Forests in West Africa, a recognised biodiversity hotspot which is increasingly threatened by habitat degradation and loss through anthropogenic impacts. The small mammal fauna of Sierra Leone is poorly documented, although bats and rodents account for the majority of mammalian diversity. Based on morphological, genetic and echolocation data, we recorded 30 bat (Chiroptera), three shrew (Soricomorpha) and eleven rodent (Rodentia) species at the Seli River in the north of the country in 2014 and 2016, during a baseline study for the Bumbuna Phase II hydroelectric project. In 2016, 15 bat species were additionally documented at the western fringe of the Loma Mountains, a recently established national park and biodiversity offset for the Bumbuna Phase I dam. Three bat species were recorded for the first time in Sierra Leone, raising the total number for the country to 61. Further, two bat species are threatened and endemic to the Upper Guinean Forest and several taxa of small mammals are poorly known or represent undescribed species. Overall, the habitats of the project area supported a species-rich small mammal fauna including species of global conservation concern. Suitable mitigation measures and/or offsets are necessary to maintain biodiversity and ecosystems in a region that is under high human pressure.

The present paper has two aims: 1) to present the results of the study of selected species of Orthoptera Tettigoniidae collected in the Guinean forests of West Africa and in the important hotspot of Dzanga-Ndoki National Park (Central African Republic); 2) to carry out a check-list of six subfamilies of Tettigoniidae (Pseudophyllinae, Conocephalinae, Hexacentrinae, Phaneropterinae, Mecopodinae and Hetrodinae) living in Central-West tropical Africa, in particular in two main tropical forests, in the subregion of upper Guinea, and in the subregion Nigeria-Cameroon plus the biodiversity hotspots of Central African Republic and Gabon. Many new records are reported and the following new species are described: Plangia astylata n. sp. from Central African Republic and Gabon, Plangia chopardi n. sp. from Côte d’Ivoire, and Catoptropteryx lineata n. sp. from Liberia. In addition the male of Plangia karschi Chopard, 1954 is described and some taxonomical notes on the recently described Arantia marginata Massa, 2021 are discussed. The new name Pseudorhynchus raggei is proposed for Pseudorhynchus robustus Ragge, 1969, junior primary homonym of Pseudorhynchus robustus Willemse, 1953. Then, the author lists all the Tettigoniidae of the above listed subfamilies presently known in central-west tropical Africa (Guinean forests). This wide tropical area holds important biodiversity hotspots that the author highlights through the study of katydids. Many groups of species tend to isolate and speciate probably more than other groups of insects. Overall, the total number amounts to 332 species, of which 242 live in Cameroon-Nigeria subregion plus Central African Republic and Gabon, 216 in the Upper Guinea subregion. The occurrence of endemic taxa is 35.9 and 40.3%, respectively; this resulted a very high percentage compared to that known for plants and animals in the area. Starting from the list of Tettigoniidae three remarkable biodiversity hotspots were examined, Dzanga-Ndoki National Park (Central African Republic), Mt. Tonkoui and Taï National Park (both in Côte d’Ivoire); overall they hold 134, 81 and 88 species, respectively. It seems that in tropical Africa there is a specific richness gradient with an East-West impoverishment, but also a possible increase of endemism occurrence. However, presently this richness suffers a high decline risk, due to deforestation and environmental degradation, in turn dependent on the inequality between human populations, wars and political instability in some tropical areas.

The cetoniine fauna of Ghana (Coleoptera: Scarabaeidae: Cetoniinae, excluding the tribes Valgini and Trichiini) is presented based on results from the Ghana Insect Project (GIP). Data from 1,571 specimens including the species and number found at each of 16 collecting sites, collecting methods, months collected, ‘common’ species and habitat associations are presented. The fauna now consists of 109 species in 51 genera. Previously known distributions and specimen label data are given for 31 species (including Genuchina, a subtribe of Cremastocheilini) recorded from Ghana for the first time.Comparisons with the works of Endrödi (1973, 1976) and Joly (2001) are made and several misidentifications are annotated and corrected. GIP results suggest moist evergreen/semi-deciduous forest and Guinea savanna/semi-deciduous forest are species-rich habitats. Faunal lists for four protected areas (Ankasa Resource Reserve, Atewa Range Forest Reserve, Bia National Park and Mole National Park) sampled by both the GIP and Joly (2001, 2011) are presented.PAST (Hammer et al., 2001) was used to estimate GIP inventory completeness through individual rarefaction. EstimateS (Colwell, 2009) was used to estimate total species richness using several classic nonparametric species richness estimators. Based on a data matrix of species abundances from each of the 16 GIP sites, the Chao 2 estimator stabilizes at ca. 113 taxa, and the jackknife 2 estimator at ca. 130 taxa. Richness estimates based on a broader, incidence-based matrix from all three sources GIP, Endrödi (1973, 1976) and Joly (2001, 2011) were: Chao 2 = 153, jackknife 1 = 157, jackknife 2 = 173. Additional sampling in under-sampled habitats such as wet and moist evergreen forest and Guinea savanna, and during the dry and early wet seasons should yield additional species.

Sierr a Leone is part of the Upper Guinean Forests with a climate that enhances great floral biodiversity. The exploitation of forest resources in Sierra Leone has seen a steady increase over the years while the establishment of forest plantations has witnessed a drastic decline. The relationship between forest exploitation and plantation forest decline is broadly assumed to be influenced by population growth, weak forest policies, legislatures, forest management and monitoring policies over the past century. The paper examines forests status and forest resources policy evolution since the pre-colonial era but pays particular attention to policies developed from 1988, in the post-colonial era, and the challenges facing their implementation. The paper highlights major challenges facing the healthy and sustainable growth of forest resources in Sierra Leone. The challenges range from the attachment of the Forestry Division to the Ministry of Agriculture, Forestry and Food Security (MAFFS), the overlap in ministerial mandates about forest protection, corrupt government officials, poverty, illegal logging, inadequate funding and staff, natural disaster and outdated forestry instruments. Natural factors such as climate change, drought, and landslides are considered among the issues affecting the sustainable expansion of forest resources in Sierra Leone. A flowchart of forest sustainability challenges in Sierra Leone was designed, and classified forest challenges into natural and man-made causes. The inability of the Forestry Division to become an independent body and the continued reliance of the Division on the 1988 Forestry Act to make informed decisions in the 21st century is serving as a major barrier in sustaining forests resources in Sierra Leone. Improving forest management in the country requires the collective efforts of both national and international forests protections entities and organizations. Sound forests conservation policies and adequate funding and staffing can strengthen the Forestry Division in enforcing its constitutional mandates. Adopting the best practices models from countries such as China, India and the USA will help towards the goal of managing forest resources sustainably for current and future generations.

Nothofagus species dominate the upper canopy of some New Caledonian rainforests on ultramafic soils. The characteristics of Nothofagus that facilitate its dominance of these forests are uncertain, but may include a superior capacity to resist the severe soil conditions. In this study, we compared foliar concentrations of macronutrients and heavy metals of Nothofagus species from ultramafic soils in New Caledonia with those from non-ultramafic soils in New Guinea. The concentrations of N and P were significantly lower (4–5-fold difference) and Fe, Cr and Ni significantly higher (140–600-fold difference) in the New Caledonian soils than in the New Guinean soils. The magnitude of difference between the two regions in mean foliar mineral concentrations was considerably less. Analysis of the full leaf data set indicated significant differences between the five New Caledonian and five New Guinea species only in P (c. 2.5-fold higher in New Guinean species) and Cr (c. 6-fold higher in New Caledonian species). The absence of significant differences between regions for most foliar elements is associated with leaf : soil ratios (foliar concentration : soil concentration) that show negative correlations with soil mineral-element concentrations. The highest leaf : soil ratios were recorded in New Caledonian species in K and Ca : Mg. The lowest ratios were recorded in the New Caledonian species in Cr, Ni and Fe. There is no evidence of accumulation of heavy metals in the New Caledonian species, with foliar concentrations similar to those of other New Caledonian species growing on non-ultramafic soils. Instead, the limited evidence suggests they are 'excluders'. In general, the New Caledonian Nothofagus species appear to have relatively low foliar concentrations of macronutrients compared with other New Caledonian rainforest species, suggesting that canopy dominance may be in part due to high nutrient efficiency in terms of growth rate per unit nutrient uptake.

Il est clairement établi que les forêts à caractère sacré ne sont pas que des créations socioculturelles émanant de sociétés traditionnelles comme cadre privilégié d'accomplissement de diverses cérémonies rituelles, mais représentent aussi des formes locales de conservation de la biodiversité. C'est ce dernier rôle qui attire toute l'attention des institutions internationales, des états et des scientifiques. Bien que de telles forêts aient été largement étudiées en Asie et dans d'autres parties de l'Afrique, notre compréhension des forêts sacrées de la Guinée reste pauvre. En effet, ces forêts sont placées, en raison de leur statut sacré, sous l'entière responsabilité des communautés locales et non l'état. Dans ce travail de thèse, quatre cas représentatifs ont été retenus en Haute Guinée, dans les localités proches de Kankan. C'est l'une des régions dont les écosystèmes sont les plus anthropisés par l'agriculture et les activités minières. Les villages de Diankana, Tintioulenkoro et Dossori font partie des rares où des forêts à caractère sacré sont encore maintenues. L'objectif de cette thèse est de diagnostiquer les valeurs socioculturelles et écologiques de ces forêts, dans un contexte local fort d'anthropisation, en vue de leur documentation et de l'élaboration des stratégies d'une gestion durable. Plusieurs approches méthodologiques ont été utilisées : enquêtes sociologiques et ethnobiologiques, inventaires écologiques et botaniques. L'étude révèle un mode de gestion des forêts sacrées qui connaît une évolution chez les Malinkés, reposant à la fois sur des ''codes mythiques'' et des lois définies par la législation traditionnelle. La rigueur dans la gestion et le rôle des forêts pour les populations sont des atouts. Toutefois, les mutations sociales relativement récentes, l'agriculture et l'urbanisation fragilisent le système et pénalisent la conservation. L'analyse diachronique démontre qu'au cours de ces trois dernières décennies, le couvert forestier de l'ensemble des sites sacrés étudiés a connu un recul moyen d'environ 40 % de leur superficie initiale par l'agriculture et l'urbanisation. [...]<br>It has been widely reported that sacred forests are not just socio-cultural creations emanating from traditional societies as a privileged setting for ritual ceremonies, but that they also represent important local forms of biodiversity conservation. In recent decades, it is this latter role that has attracted the attention of international institutions, states and scientists. Although such forests have been widely studied in Asia and other parts of Africa, our understanding of Guinea's sacred forests remains poor because local communities, not the state, manage them. In effect, because of the sacred status of these forests, the state favours local management strategies by individual communities. In this thesis, four representative case studies of the sacred forests of Upper Guinea, located near Kankan, are studied. The region's ecosystems have been profoundly affected by human impacts, notably agriculture and mining. The villages of Diankana, Tintioulenkoro and Dossori, where these forests are amongst the few areas to conserve sacred forests. The aim of this thesis is to probe the socio-cultural and ecological values of the forests, in a local context of strong human pressures, with a view to their documentation and the elaboration of sustainable management strategies. Several methodological approaches have been used: sociological and ethno biological surveys, ecological and botanical inventories. The study elucidates a mode of management of these sacred forests by an ethnic group, the Malinkés, which is based on both "mythical codes" and laws defined by traditional legislation. The rigor of this management system, and the socio-cultural importance of these forests for local populations, favours their conservation in the wider context of profound human pressures on the environment. However, social changes in recent years appear, agriculture and urbanisation to have weakened this management system and exposed the area's sacred forests to factors that preclude their effective conservation. The diachronic analysis shows that over the last three decades, the forest cover of all sacred sites studied has decreased by just over 40% of their initial area by agriculture and urbanization. [...]

Amphibienpopulationen sind weltweit bedroht. Für fundierte Entscheidungen im Naturschutz ist ein wissenschaftliches Hintergrundwissen notwendig. Eine wichtige Komponente ist die Verbreitung der Arten und die Gründe hierfür. Dies setzt auch Klarheit bezüglich des taxonomischen Status voraus. Vernachlässigte Regionen liegen meist in den Tropen. Um diese Lücke zu füllen, untersucht die vorliegende Arbeit die Makroökologie westafrikanischer Amphibien. Eine neue Art der Familie Phrynobatrachidae wird beschrieben. Anschließend werden die taxonomischen Unterschiede zweier Mitglieder der Familien der Hyperoliidae und der Arthroleptidae untersucht. Dies ebnet den Weg für die Makroökologie. Es wird analysiert, ob Westafrika eine einzigartige biogeographische Region ist. Die Untersuchung zeigen, dass Westafrika in der Tat einzigartig ist. Die Ähnlichkeiten innerhalb der Region sind größer als die innerhalb ähnlicher Habitate aus unterschiedlichen Regionen. Der Cross River ist die wichtigste Barriere. Mehrere geographische Zonierungen innerhalb Westafrikas werden entdeckt. Es wird untersucht, ob der Chytrid Pilz, Batrachochytrium dendrobatidis, (Bd), ein wichtiger Faktor beim Rückgang der Amphibien Populationen, in West Afrika vorkommt. Bisher gibt es keinen positiven Nachweis westlich Nigerias. Dennoch sagen Modelle geeignete Habitate für Bd vorher. Die wahrscheinlichste Erklärung ist, dass die Dahomey Gap als natürliche Barriere die Ausbreitung von Bd verhindert. Als letztes werden die Nischen westafrikanischer Amphibien eruiert. Für die meisten Arten werden Nischenmodelle berechnet. Dies bestätigt bereits bekannte Gebiete hoher Alpha Diversität und zeigt bisher unbekannte Gebiete auf. Des Weiteren werden Erklärungen für unterschiedliche Verbreitungsgebietsgrößen gesucht. Generell wird die Nischenbreite hierfür verantwortlich gemacht. Die vorliegenden Daten lassen allerdings auch den Schluss zu, dass das Ausbreitungsvermögen das beobachtete Muster ebenfalls erklären kann.<br>Amphibian populations are declining globally. For informed conservation decisions a sound scientific background is needed. One major component is species distribution and the underlying causes. This also requires clarity on the taxonomic status. Often neglected regions are located in the tropics. In order to fill this gap, the present thesis examines the macroecology of West African amphibians. A new species of the family Phrynobatrachidae is described. Afterwards, the taxonomic differences between morphologically similar members of the families Hyperoliidae and Arthroleptidae are discussed. Beside other studies, this sets the field for macroecology. It is tested whether West Africa is a unique biogeographic region. The similarity of amphibian assemblages from Sub-Saharan Africa is analysed and it is shown that West Africa contains unique assemblages. Similarities within the region are higher than similarities between habitats across different regions. The main barrier towards Central Africa is the Cross River. Several geographic divisions within West Africa are detected. It is examined whether the chytrid fungus Batrachochytrium dendrobatidis (Bd), one important factor for amphibian population declines in many other regions, occurs in West Africa. So far there is no positive record west of Nigeria. However, models predict that environmental suitability for Bd is high. The most plausible explanation for the absence is that the Dahomey Gap acted as a natural barrier against the spread of the Bd. Finally, the niches of West African amphibians are investigated. For most species environmental niche models are calculated. This confirms previously known areas of high alpha diversity and so far unknown species rich areas are detected. In a further study, explanations for differing range sizes are searched for. Niche breadth is commonly assumed to be the general cause. However, the analysed data also suggests that dispersal ability can also explain the observed pattern.

East and South-East Asia is a vast and diverse region (Fig. 6.1). The northern boundary can be taken as approximately 45 degrees latitude, from the Gobi desert on the west across Manchuria to the northern shores of Hokkaido, the main island of northern Japan. The southern boundary is over 6,000 kilometres away: the chain of islands from Java to New Guinea, approximately 10 degrees south of the Equator. From west to east across South-East Asia, from the western tip of Sumatra at 95 degrees longitude to the eastern end of New Guinea at 150 degrees longitude, is also some 6,000 kilometres. Transitions to farming within this huge area are discussed in this chapter in the context of four major sub-regions: China; the Korean peninsula and Japan; mainland South-East Asia (Vietnam, Laos, Cambodia, Thailand, the Malay peninsula); and island South-East Asia (principally Taiwan, the Philippines, Sumatra, Java, Borneo, Sulawesi, and New Guinea). The chapter also discusses the development of agricultural systems across the Pacific islands to the east, both in island Melanesia (the Bismarck Archipelago and the Solomon Islands east of New Guinea) and in what Pacific archaeologists are terming ‘Remote Oceania’, the islands dotted across the central Pacific as far as Hawaii 6,000 kilometres east of Taiwan and Easter Island some 9,000 kilometres east of New Guinea—a region as big as East Asia and South-East Asia put together. The phytogeographic zones of China reflect the gradual transition from boreal to temperate to tropical conditions, as temperatures and rainfall increase moving southwards (Shi et al., 1993; Fig. 6.2 upper map): coniferous forest in the far north; mixed coniferous and deciduous forest in north-east China (Manchuria) extending into Korea; temperate deciduous and broadleaved forest in the middle and lower valley of the Huanghe (or Yellow) River and the Huai River to the south; sub-tropical evergreen broad-leaved forest in the middle and lower valley of the Yangzi (Yangtze) River; and tropical monsoonal rainforest on the southern coasts, which then extends southwards across mainland and island South-East Asia. Climate and vegetation also differ with altitude and distance from the coast.

El-Nino is a periodic flow of warm Pacific equatorial waters southward, usually around Christmas time. El-Nino is linked to the Southern Oscillation and it affects the atmosphere, disrupting weather condition of the world. Its disastrous effects have resulted in drought in Australia and Papua New Guinea, a delayed monsoon in South-East Asia leading to massive forest fires choking smog, storms on the Pacific coast of South and Central America, drought in Southern Africa, and threat of flood in Peru and California. Its increasing sensitivity and frequency through the 1980s and 1990s, suggests that El-Nino is affected by an increase of heat trapping greenhouse gases in the upper atmosphere. Global Warming could make the El-Nino a permanent feature of world`s weather system. El-Nino and Southern Oscillation largely affect developing countries that are largely depending upon fishery and agriculture for employment, foreign exchange, and food supply. Global warming increases severity and frequency of El-Nino which has great socio-economic impact on these countries.