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In spite of the provisions of forest management prescriptions for forests in Ghana, forest degradation and deforestation are very high. This paper contributes to the discourse on sustainable forest management in Ghana by documenting the gaps in the implementation of forest management prescriptions and forest users' compliance with forest regulations. We used desk study, field observations and measurements, interviews as well as focus group discussions to solicit for information from different stakeholder groups. The study showed major gaps between the application of official forest management prescriptions and their practical implementation, as well as lack of compliance of logging regulations. These gaps encouraged forest encroachment, illegal exploitation of wood and wood products and undermine the effective generation of forest management data for planning and forest management decision support. Furthermore, poor compliance to management regulations was noted to constitute a critical factor limiting the achievement of forest management objectives. Reasons assigned to these gaps reflect institutional weaknesses and the constraints of resource under which such institutions operate. Therefore, as Ghana implements forest management mechanisms such as the Forest Law Enforcement, Governance and Trade and Reducing Emissions from Deforestation and forest Degradation (REDD+), attention should be focused on factors hindering the implementation of management prescriptions and compliance with forest regulations. [ABSTRACT FROM AUTHOR]

Our study assessed the effectiveness of species debarking in controlling species invasion and the change in seedling dynamics after application of the different treatments. A split plots design was used in two forest reserves to assess the effectiveness of three debarking treatments: complete ring debarking, partial ring debarking and a control (no debarking). The results reveal that ring debarking has the potential to be used to control invasive species such as Cecropia peltata L. and Broussonetia papyrifera (L.) Vent. The efficiency, however, was influenced by the extent of the wound created and the size of tree, especially if trees are partially debarked. The control method also stimulated natural regeneration of native species with higher regeneration of native species recorded compared to invasive species. Also, plots that had completely debarked trees had higher species diversity than the partially debarked and the control plots in one of the reserve. The fact that none of the trees in the control plots died is indication of the effectiveness of debarking in the control of invasive species considered here. The effectiveness of this method suggests it is a suitable option for killing small to medium size trees with little cost to the environment compared to the application of arboricides for instance and is therefore worth revisiting in silvicultural treatments where minimum environmental disturbance is required. We recommend more studies to compare the effectiveness of the control approaches on different invasive species and monitor how the native communities respond including in terms of species diversity and functional groups, since removal methods may impact differently on these plant community traits. [ABSTRACT FROM AUTHOR]

Tropical forests harbour significant proportion of global biodiversity. Recent studies are, however, reporting an increase in plant invasion and its effect on these forests. We surveyed three forest reserves in Ghana to determine how differences in invasion levels influence plant community structure. Species diversity and species richness, particularly pioneer and non-pioneer light demanders, decrease with increasing invasion level. There was no consistent pattern regarding the impact of different levels of invasion on the diversity of the different tree functional groups. Stand density of native trees were the same in two of the reserves whilst the basal area of the highly invaded sites was higher than that of the lightly invaded sites in two of the three reserves. Generally, while there are some patterns in diversity indices and functional groups that are broadly maintained across the three reserves, site-specificity was also important, with the direction of impact influenced by the type of species and habitats. The study adds to the growing body of evidence that ecological impacts of invasive species do not always increase proportionally with invader density but are complex and context-dependent. It also provides insights into silviculture and other forest management decision-making and interventions, with respect to invasive tree species in forest reserves. [ABSTRACT FROM AUTHOR]

The paper provides an inventory of the naturalized vascular flora of Ghana, based on newly gathered information from the literature and consultations with local experts. We adopted a rather conservative approach by including only species for which strong evidence exists that they are alien in Ghana. We recorded 291 species of naturalized alien plants; for 237 of them there is information on their distribution in the 10 administrative regions of Ghana. Twenty-five species (i.e. 8.6% of the total number of naturalized species) are classified as invasive. There are 21 widely distributed species (7.2% of the total naturalized flora) that occur in at least eight regions, and five of them are distributed all over the country: Azadirachta indica, Echinochloa colona, Leucaena leucocephala, Senna occidentalis and S. siamea. Of these five, the first three are classified as invasive. The naturalized flora of Ghana includes 71 families, with Leguminosae (66 species), Compositae (22) and Poaceae (18) most represented. The majority of species have their native range in South and North America, contributing 161 and 127 species, respectively. Tropical Asia (98 species) and Africa (37 species) are less represented and only three species have their origin in Europe. The dominance of the Americas as a source region is even more pronounced for the subset of invasive species, with this continent accounting for 18 species out of 25 (72%). Annual and biennial/perennial herbs, shrubs and trees are evenly represented in the naturalized alien species pool. Among invasive species, biennial/perennial herbs are markedly over-represented compared to their contribution to the naturalized flora as a whole (52% vs 38%). The same is true for aquatic species (12% vs 2%). Species that occur as naturalized in more than 40 regions in Africa are also more widely distributed within Ghana. The numbers of naturalized species in the administrative regions of Ghana varied from 34 in Upper West to 173 in Greater Accra. These numbers increased with human population density and decreased with distance from the sea, but this pattern was driven by the city of Accra region. The only predictor that remained significant after removing this outlier was the amount of precipitation in the dry period, which was positively associated with the regional richness of naturalized species. This study could serve as a stimulus for other countries in hitherto understudied tropical regions to work towards comprehensive inventories, for which basic data on the alien flora often is still incomplete. [ABSTRACT FROM AUTHOR]