Browsing by Author "Asare, R."
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Item Assessment of groundwater quality and its suitability for domestic and agricultural purposes in parts of the Central Region, Ghana(Ecological Laboratory, 2016) Asare, R.; Sakyi, P.A.; Fynn, O.F.; Osiakwan, G.M.Groundwater in parts of the Central Region of Ghana was assessed to determine its suitability for domestic use and irrigation activities. Stiff and Piper diagrams show that the predominant water type in the area is Na-Cl, which is characterized by relatively high salinities. This water type occurs in aquifers underlying six coastal districts, namely; Abura-Asebu-Kwamankese (AA), Mfantseman (MF), Gomoa East (GE), Awutu Senya (AwS), Effutu (EF) and Cape Coast (CC). Other water types are Ca-HCO3, Ca-SO4 and Ca-Cl, that occur in districts located further away from the coast. Silicate weathering and ion exchange are identified as the geochemical processes responsible for the various ions in the groundwater. Possible processes that could be responsible for the source of Na+ and Cl- are sea water intrusion and dissolution of minerals. The results also show that the groundwater is mainly supersaturated with respect to both calcite and gypsum, indicating high concentrations of both bicarbonate and sulfate ions in solution. This is associated with considerable enrichment of the groundwater with sulfate, bicarbonate, and calcium ions. On a Wilcox diagram, the groundwater samples, mainly from the districts coded as AA, TLD, AS and AN, which are located away from the coast, plot within the “excellent to good” category, suggesting that water from the area is of acceptable quality for irrigation purposes. Similarly, Sodium Adsorption Ratio (SAR) and conductivity values for the groundwater in the AA, TLD, AS and AN districts indicate low SAR and low to medium salinity respectively. Groundwater in aquifers underlying these districts is therefore suitable for irrigation. Generally, groundwater samples from locations along the coast have high salinity and are not suitable for domestic and irrigation purposes. However, about 72% of the water samples predominantly in districts located away from the sea is suitable for the purposes stated. © 2016, Ecological Laboratory. All rights reserved.Item Cocoa agroforestry for increasing forest connectivity in a fragmented landscape in Ghana(Agroforestry Systems, 2014-12) Asare, R.; Afari-Sefa, V.; Osei-Owusu, Y.; Pabi, O.In Ghana, farmers perceive protected forests as land banks for increasing agricultural productivity to support subsistence living. This has led to fragmentation of existing protected forests. Two of such reserve forests namely Bia Conservation Area and Krokosua Hills Forest Reserve have been encroached through lumbering for timber and area expansion of no-shade cocoa production systems. The purpose of this study was to develop a multi-disciplinary strategy to increase forest connectivity using cocoa agroforest corridors. Biophysical assessments involving satellite images for vegetation patterns, and expert data from a decision support system were used to select suitable sites for the corridor within a Geographic Information System framework. Socio-economic assessments of the opportunity costs of alternative farming systems to cocoa agroforestry in the delineated corridors show that while timber trees planted within cocoa agroforests settings would help offset the yield losses in cocoa shade-yield relationships compared to full sun-production systems, the on-farm benefits of cocoa agroforestry alone are insufficient to justify the adoption. Paying farmers premium prices for cocoa and substantial off-farm environmental and ecosystem services under agroforestry systems can tip the balance towards adoption. © 2014, Springer Science+Business Media Dordrecht.Item Combined effects of shade and drought on physiology, growth, and yield of mature cocoa trees(Science of the Total Environment, 2023) Mensah, E.O.; Ræbild, A.; Asare, R.; et al.Climate models predict decreasing precipitation and increasing air temperature, causing concern for the future of cocoa in the major producing regions worldwide. It has been suggested that shade could alleviate stress by reducing radiation intensity and conserving soil moisture, but few on-farm cocoa studies are testing this hy pothesis. Here, for 33 months, we subjected twelve-year cocoa plants in Ghana to three levels of rainwater suppression (full rainwater, 1/3 rainwater suppression and 2/3 rainwater suppression) under full sun or 40 % uniform shade in a split plot design, monitoring soil moisture, physiological parameters, growth, and yield. Volumetric soil moisture (ϴw) contents in the treatments ranged between 0.20 and 0.45 m3 m− 3 and increased under shade. Rainwater suppression decreased leaf water potentials (ѱw), reaching − 1.5 MPa in full sun con ditions indicating severe drought. Stomatal conductance (gs) was decreased under the full sun but was not affected by rainwater suppression, illustrating the limited control of water loss in cocoa plants. Although pre dawn chlorophyll fluorescence (Fv/Fm) indicated photoinhibition, rates of photosynthesis (Pn) were highest in full sun. On the other hand, litter fall was highest in the full sun and under water stress, while diameter growth and carbon accumulation increased in the shade but was negatively affected by rainwater suppression. Abortion of fruits and damage to pods were high under shade, but dry bean yield was higher compared to under the full sun. The absence of interactions between shade treatments and rainwater suppression suggests that shade may improve the performance of cocoa, but not sufficiently to counteract the negative effects of water stress under field conditions.Item Ghana's quest for oil and gas: Ecological risks and management frameworks(West African Journal of Applied Ecology, 2012-01) Sakyi, P.A.; Efavi, J.K.; Atta-Peters, D.; Asare, R.Ghana discovered commercial oil and gas in 2007, and, subsequently, commenced production in the last quarter of 2010. In the light of the potential economic boost that will accompany petroleum production, its discovery was welcome news for Ghanaians. However, oil exploration and production involve several activities that can have detrimental impacts on the ecosystem. In this paper, the potential sources of pollution in the upstream sector of the oil and gas industry and their effects on the environment are discussed. Also discussed are existing national environmental management legislations in the extractive industry, and the implementation and enforcement challenges these regulations face. Strategies to curtail the effects of oil and gas development on the ecosystem are also put forward. These include the need for government to formulate petroleum industry-specific environmental protection guidelines and appropriate regulatory frameworks. Such regulations in managing the environment should employ an integrated approach involving (i) prescription of environmental codes and setting of standards by government to be met by operators, and (ii) the need for oil companies to develop environmental management system (EMS) to ensure that they operate within the environmental standards for the industry. Administrative and institutional restructuring and reforms, as well as the provision of the necessary financial and human resources for the various environmental agencies, should be encouraged to ensure effective implementation, enforcement and monitoring.Item Limited effects of shade on physiological performances of cocoa (Theobroma cacao L.) under elevated temperature(Environmental and Experimental Botany, 2022) Mensah, E.O.; Asare, R.; Vaast, P.; Amoatey, C.A.; Markussen, B.; Owusu, K.; Asitoakor, B.K.; Asitoakor, A.Shade is one of the recommended management solutions to mitigate the effects of heat stress, which is a major challenge for cocoa production globally. Nevertheless, there are limited studies to verify this hypothesis. Here, we evaluate the effects of heat and shade on cocoa physiology using experimental plots with six-month old potted seedlings in a randomized complete block design. Infrared heaters were applied for one month to increase leaf temperatures by an average of 5–7 ºC (heat treatment) compared with no heat (unheated treatments), and shaded plants were placed under a shade net removing 60% of the light compared with no shade (sun treatments). Plants under heat treatments in sun and in shade showed severe reduction in photosynthesis. Measurements of chlo rophyll fluorescence and photosynthetic light response curves indicated that heat caused damages at photo system II and additionally resulted in lower rates of maximal photosynthesis. Temperature optima for photosynthesis were at 31–33 ºC with only small differences between treatments, and as light saturation was reached at low PAR levels of 325 – 380 µmol m− 2 s − 1 in shade and 427 – 521 µmol m− 2 s − 1 in sun, ambient rates of photosynthesis were comparable between sun and shade treatments. Heat treatments resulted in decreased concentrations of chlorophyll and changed pigment composition, reduced specific leaf areas, and plant biomass. While shade may benefit cocoa seedlings, our results indicate that the positive effects may not be sufficient to counteract the negative effects of increased temperatures on cocoa physiology.Item The Role of Innovation in Sustainable Cocoa Cultivation: Moving Beyond Mitigation and Adaptation(Palgrave Macmillan, Cham, 2023) Boadi, S.A.; Owusu, K.; Olwig, M.F.; Asare, R.; Bosselmann, A.S.Cocoa cultivation is both severely threatened by climate change and a potential contributor to climate change through deforestation. Based on a review of the literature and secondary documents, as well as field observations and interviews, this chapter examines different innovations in Ghana’s cocoa sector, the ways in which they aim to address sustainable cocoa cultivation, and the challenges to their adoption. We find that cocoa farmers are generally open to innovation and new technology. Yet, while farmers respond positively to certain innovations, they do not fully adopt others. This uneven adoption, we argue, is not just a result of limited resources or poor extension services but stems from a failure to address the multiple challenges farmers face when introducing new innovations, including insecure land-use rights, youth disinterest, migration, and seemingly lucrative alternative land use. While promising innovations, such as agroforestry and smartphone applications for agricultural service delivery and training, are currently being implemented, such innovations, we conclude, will only lead to sustainable cocoa cultivation if these broader challenges are addressed, thereby moving beyond a narrower concern with yields and climate change mitigation and adaptation