Allometric relationships between stem diameter, height and crown area of associated trees of cocoa agroforests of Ghana.

Allometric models which are used to describe the structure of trees in agroforestry systems are usually extrapolated from models developed for trees in forest ecosystems. This makes quantitative assessment of the functions of shade trees in agroforestry systems challenging since increased availability of light and space in these systems may induce structural differences from those growing under forest conditions. We addressed this issue by providing species-specific allometric information on the structural characteristics of associated shade trees on cocoa agroforestry systems and assessed if allometries conformed to theoretical predictions.

Mining methods exert differential effects on species recruitment at artisanal small-scale mining sites in Ghana.

Artisanal small-scale mining (ASM) is one of the essential rural non-agricultural livelihood activities in Ghana. However, basic and rudimentary practices and tools associated with ASM activities lead to vegetation and soil destruction. Given the limitation of state-sponsored reclamation of abandoned ASM sites, the role of natural recovery in abandoned mine sites is deemed a viable option, as it lowers financial obligations, promotes pioneer species and improves local ecology.

Factors shaping local people's perception of ecosystem services in the Atacora Chain of Mountains, a biodiversity hotspot in northern Benin.

Background: Atacora Chain of Mountains (ACM) is the Benin part of a range of mountains lying from Benin to Ghana through Togo. It provides goods and services to people and is dominated by rural communities with heavy reliance on natural resources. The ACM may be threatened by the increasing resource needs and the possible shift in people's livelihood priorities brought about by challenges and opportunities ushered in by modernization.

Rainfall seasonality and drought performance shape the distribution of tropical tree species in Ghana.

Tree species distribution in lowland tropical forests is strongly associated with rainfall amount and distribution. Not only plant water availability, but also irradiance, soil fertility, and pest pressure covary along rainfall gradients. To assess the role of water availability in shaping species distribution, we carried out a reciprocal transplanting experiment in gaps in a dry and a wet forest site in Ghana, using 2,670 seedlings of 23 tree species belonging to three contrasting rainfall distributions groups (dry species, ubiquitous species, and wet species).

The effects of drought and shade on the performance, morphology and physiology of Ghanaian tree species.

In tropical forests light and water availability are the most important factors for seedling growth and survival but an increasing frequency of drought may affect tree regeneration. One central question is whether drought and shade have interactive effects on seedling growth and survival. Here, we present results of a greenhouse experiment, in which seedlings of 10 Ghanaian tree species were exposed to combinations of strong seasonal drought (continuous watering versus withholding water for nine weeks) and shade (5% irradiance versus 20% irradiance).