No abstract

The positive ecological interaction between gap formation and natural regeneration has been examined but little research has been carried out on the effects of gaps on natural regeneration in forests under different intensities of disturbance. This study evaluates the composition, diversity, regeneration density and abundance of natural regeneration of tree species in gaps in undisturbed, intermittently disturbed, and disturbed forest sites. Bia Tano Forest Reserve in Ghana was the study area and three gaps each were selected in the three forest site categories. Ten circular subsampling areas of 1 m2 were delineated at 2 m spacing along north, south, east, and west transects within individual gaps. Data on natural regeneration < 350 cm height were gathered. The results show that the intensity of disturbance was disproportional to gap size. Species diversity differed significantly between undisturbed and disturbed sites and, also between intermittently disturbed and disturbed sites for Simpson’s (1-D), Equitability (J), and Berger–Parker (B–P) indices. However, there was no significant difference among forest sites for Shannon diversity (H) and Margalef richness (MI) indices. Tree species composition on the sites differed. Regeneration density on the disturbed site was significantly higher than on the two other sites. Greater abundance and density of shade-dependent species on all sites identified them as opportunistic replacements of gap-dependent pioneers. Pioneer species giving way to shade tolerant species is a natural process, thus make them worst variant in gap regeneration.

The impacts of small-scale mining on the vegetal cover as well the livelihoods of communities in mined areas in developing countries such as Ghana are far-reaching. This study assessed the impacts of small-scale mining on flora of conservation and economic significance through quantification of species richness, and species diversity. Mined and unmined sites were chosen in the Dunkwa East Municipality of Ghana. Five belt transects each (200m &times; 200m) were constructed in both sites. Each belt transect was divided into 100 quadrats (20m &times; 20m) and plant species in each of the quadrat were identified in the field and or the herbarium of the School of Biological Sciences, University of Cape Coast. One hundred and fifty seven species distributed in 140 genera and 54 families were identified in the mined area whilst the 209 species identified in the unmined area were in 185 genera and 73 families. Plant families Euphorbiaceae, Rubiaceae and Asteraceae were more diverse whilst Asteraceae, Poaceae and Euphorbiaceae were dominant in the unmined area. In the mined area, however, Poaceae, Euphorbiaceae and Asteraceae were more diverse. Pteridium aquilinum, Tridax procumbens and Waltheria indica in the unmined area and Chromolaena odorata, Sporobolus pyramidalis and Euphorbia hirta in the mined area were the dominant species. Small-scale miming activities have caused reduction in species diversity, richness and economic and commercial values in the area. Higher disturbance of the flora has resulted in more secondary species in the mined area. Restoration is required in the study area.

Poor soil fertility, viral diseases and pest infestations are major constraints on the production of okra in Africa. The study was conducted to assess the effectiveness of compost in minimizing okra mosaic disease (OMD), flea beetle infestation and improving the yield and quality of okra. In a pot and two field experiments (conducted in 2014 major and minor seasons), compost was incorporated at 0 kg N ha-1 , 100 kg N ha-1 and 200 kg N ha-1 with three replicates, in a randomised complete block design using Asontem and Enidaso okra varieties as test crops. Results indicated that compost application yielded significantly higher plant height, and dry matter content and

The formation of soils in any region is influenced by many factors such as the parent materials and the secondary materials derived from them, the vegetation and the history of land use. These factors vary from place to place, and they contribute to the spatial variation in properties of the soil. Quantification of the magnitude, location, and causes of spatial variability is an essential, but insufficient ingredient of soil surveys. Soil samples from the 0-to 20-cm depth were taken covering soils in the Asuansi-Akroso-Nta-Ofin compound association (Lixisol, Cambisol, and Fluvisol association) at the study site by following the nested balanced hierarchical sampling technique. This covered distances between 100 and 0.80 m. Standard laboratory analyses were performed to quantify the selected properties, namely, pH, organic carbon, total nitrogen, total phosphorus, exchangeable potassium, and content of sand, silt, and clay. Classical statistics and geostatistical procedures were performed on the data and models fitted to the variability patterns. Physical and the more stable properties, such as sand, silt, and clay, were fitted with spherical variogram models. These models indicate a high level of spatial dependence, therefore, such properties may be said to be fairly stable in the field. On the contrary, chemical properties, such as exchangeable potassium, were fitted with exponential variogram models, indicating that these properties were less stable and showed dependence over longer distances. The scale of variation of the properties ranged between 35 and 62 m. The degree of uncertainty associated with time and space can be reduced by improved documentation of field variability using the tools of geostatistics.