Assessment of the Variations in Soil Physicochemical Parameters of the Natural Forest and Plantations in Orumba North Local Government Area, Anambra State, Nigeria

Soil physicochemical parameters are the physical and chemical characteristics of soil such as pH, bulk density, organic carbon, nitrogen content, and nutrient levels at different soil depths. These parameters vary from one vegetation to the other and from one soil to the other. The study assessed the variations in soil physicochemical parameters of the natural forest and plantations in Agu Eke (Eke bush) in Etti village, Nanka and Umunnebo village, Ufuma both located in Orumba North Local Government Area, Anambra State. The experimental research design and stratified random sampling methods were used for the study and a total of 12 soil samples were collected at 30 cm depth from the selected locations of natural forest, cashew and palm plantations. The samples were analyzed using laboratory Varian AA240 Atomic Absorption Spectrophotometer, after which the result was subjected to statistical analysis—Analysis of Variance (ANOVA). The study found that there was no significant difference (variation) between the moisture contents of natural forests and the plantations;that is, the moisture contents were the same. It was also found that there was no significant variation between the bulk densities of the natural forest, oil plantation, and cashew plantation, meaning that the bulk densities were significantly the same. However, there were significant variations in nitrogen, potassium and phosphates, with p-values: sig = .000 < .05, sig = .010 < .05 and sig = .000 < .05, respectively. That is, the nitrogen and phosphate contents of the natural forest significantly vary more than those of the oil palm and cashew plantations, which probably means that by reducing natural forest to plantation, the nitrogen and phosphate contents of the natural forest reduced from what it used to be when the lands were mere forests. This shows that plantations do not have the same function of maintaining or improving soil quality as natural forests. The study recommended adopting a sustainable plantation agricultural system, such as using diverse nutrient sources (manure and compost), in order to maintain the desired soil quality.

Species Distribution and Patterns in a Forest-savannah Ecotone: Environmental Change and Conservation Concerns

Understanding the dynamics and patterns of biodiversity in transition forests is vital in promoting conservation and addressing environmental change issues.This work focused on elucidating the diversity,structure,and carbon potentials of a forest-savannah ecosystem.To achieve this,8 forest plots that measured 50 m×50 m each was set up in a forest-savannah landscape and used to identify and measure tree species≥10 cm diameter at breast height(DBH measured at 130 cm).Species importance value was used to summarize the biodiversity patterns and the aboveground carbon estimates were elicited with the allometric equation.43 species within 22 families were enumerated and the diversity was generally low(ranging from 1.82-2.5).Species such as Daniellia oliveri(Rolfe)Hutch.&Dalziel,Py-rostria guinnensis Comm.ex A.Juss,Dialium guineense Willd.and Margariteria discoidea(Baill.)G.L Webster were the dominant species,and had the highest importance values of 113.06,55.13,28.16 and 16.95,respectively,while Allophlus africanus P.Beauv.,Annona senegalensis Pers.,Anthonatha macrophylla P.Beauv.,Ficus capensis Thumb.and Lecaniodiscus cupanioides Planch had the least importance values of 0.16 each.Carbon estimates ranged from 16.43172-42.9298 t/Ha.Most frequent species with higher basal areas no doubt contributed much to the carbon esti-mates,but did not have higher capacities in storing carbon.Managing the ecosystem with more carbon-dense species was seen as a suitable strategy for addressing environmental change in the ecosystem and region.

Swamp Forest Use and Loss in the Niger Delta: Contextual and Underlying Issues

Forest ecosystems are vital not only for the ecosystem and biogeochemical processes, but also for the livelihood of forest dependent communities for which its continual existence is a necessity. This study explored the pattern of forest use in the hinterlands of the Niger Delta and sought to elucidate the drivers of forest loss and how the ownership and management of the forest plots influenced the changes in the forest ecosystem. Ecosystem services reduction and forest loss/degradation were found to be increasing over the years due to crude oil activities, urbanization/developments, population increase, agricultural activities and natural causes like flood. While each factor contributed to forest loss directly and indirectly, and varied from community to community, agricultural activities and population growth were responsible for most of the losses across the landscape. Even though agricultural activities were essential and thrived in the region, sustainable forest (land) uses could have reduced the associated implications of such land uses;but this was however hampered by the farming practises (shifting cultivation) across most of the communities. Lack of proper, effective and sustainable forest management structures, poor individual commitment and monitoring of forest activities were found to encourage forest loss at different spatial scales. Provision of alternative sources of livelihood and ensuring that suitable guidelines on forest abstraction and harvest are enforced across the region, are steps to promoting biodiversity conservation and resource management.