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Large areas of the indigenous tropical forests in the southwestern part of Nigeria are being converted into agricultural lands and this has been reported to have serious implications for biodiversity and the environment. Cocoa based agroforestry is one of the common agricultural practices in this region and comparative information on the carbon storage capacity of the cocoa agroforests is generally lacking. In this study the above-ground carbon storage and partitioning in a protected primary forest were evaluated and compared with those of the two categories of cocoa agroforests (sparse and dense) identified in the area. Above-ground biomass accumulation and carbon stock varied significantly with land use type, with the primary rainforest having the highest values and sparse cocoa agroforests having the lowest. A reduction in above-ground carbon stock of 89.82% and 71.20% was observed 10 years after conversion of tropical rainforest to sparse and dense cocoa agroforests respectively

Remote sensing (RS) and GIS are important methods for land use assessment and land cover transition. In this study, land use/land cover changes in the Ago-Owu Forest Reserve, Osun State, Nigeria have been assessed. Landsat 5 TM, Landsat 7 ETM+ and Landsat 8 OLI were acquired for 1986, 2002 and 2017 respectively. The three scenes corresponded to path 190 and row 055 of WRS-2 (Worldwide Reference System). The processing of the imagery was preceded by the clipping of the study area from the satellite image. The boundary of the reserve was carefully digitized and used to clip the imagery to produce an image map of the forest reserve. Using the supervised image classification procedure, training sites were used to produce land use/land cover maps. The same classification scheme was used for the 1986, 2002 and 2017 images to facilitate the detection of change. The differences in the area covered by the different polygons between the three sets of images were measured in km 2. The results show that during 1986 and 2017, there is a dramatic increase of build-up areas with a change of 55.65 km 2 and sparse vegetation (farmland and grassland) with a change of 53.97 km 2 , while a dramatic decrease of dense vegetation (forest areas) with a change of 109.61 km 2. The consequence of these results is that over the years, the population of people living in the forest reserve has increased and many of them are engaged in farming, leading to an increase in farmland. In addition, logging activities continued unabated in the forest reserve, as demonstrated by a sharp increase in the deforested area within the reserve. The maps produced in this study will serve as a planning tool for the Osun State Forestry Department to plan reforestation activities for the forest reserve.

Over the years, cereals have been the major food consumed by humans and have also been used in animal diet and therefore highly commendable for playing a major role in the preservation of human race. Studies have shown that half of the total percentage of calories consumed in the world is from cereals while it is also the most traded agricultural crop at the international market. This motivates the need to assess its utilisation in the past, present and future. This review shows that much driven by the use of cereals are factors like consumption and dietary pattern of a person or country, technological advancement in adding value to it, income status, market forces of demand and supply, level of affluence and policy. The trend in global cereals utilisation since its domestication has indicated an upward one with bulk of it being consumed as food in developing countries while majority of it goes into feeding livestock in developed countries. Evidence from this study also shows that the per capita utilisation of cereals directly for food is exceedingly great in developing countries than developed countries which is an indicator of malnutrition when not balance with other nutrients as it was observed in Bangladesh where calorie intake of an adult is about 90% from cereals. While there is a steady increase in global cereals utilisation due to its discovered industrial use as fuel, increased population and other factors, it will be expedient to focus on its sustainability and environmental issues that are likely to come up as a limitation to meet future demands.

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