1,010 research outputs found

    Moisture availability and agricultural potentialities of Mali and Niger

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    One of the greatest factors limiting agricultural development in arid and semi-arid regions of Africa is lack of moisture. A country with adequate moisture has a great potential for agricultural development. It is againts this background that this paper focuses on the application of Hargreaves monthly moisture availability index classification to Mali and Niger in West Africa. The two countries are classified into moisture regions on the basis of the index and their relative agricultural potentials are assessed

    Food Crisis In Africa

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    ABSTRACT in most cases the chronic food crisis in Africa has been ascribed to natural calamities such as drought. it is the primary objective of this paper to examine the political, economic and social factors which have and continue to militate against food production in Africa The paper while accepting that natural disasters have contributed to the food crisis makes it vividly clear that the policies of development by various, African governments have contributed most greatly to Africa\u27s food predicament Kata Kunci : food crisi

    Rice Fields Chemical and Physical Properties and the Implications on Breeding Strategie

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    Soil related constraints are major limiting factors in crop production in the Sahel. The objective of this study was to assess the properties of farmer's fields soil and irrigation water in Niger and the implications in rice improvement. Composite soil samples were collected from irrigated and non-irrigated fields. Sample of irrigation water was also collected. Physical and chemical analyses were performed in the laboratory. The results showed that most of rice fields were clayey and the non irrigated ones were mostly sandy. The soils were acidic and saline, the electrical conductivity ranged from 2.2 to 16.5 decisiemens per meter. The T-test showed that total dissolved salt, sodium adsorption ratio, cation exchange capacity, and organic matter percentage were significantly higher in irrigated fields than non-irrigated fields. The irrigated soils pH varied from 3.2 to 6.8, the electrical conductivity was greater than 4, and the sodium adsorption ratio was below 13 while the exchangeable sodium percentage was below 15. The irrigation water samples varied in term of ion content from site to site. The total sodium quantity estimated to be deposited varied from 87 kg/ha/year to 218 kg/ha/year. Rice fields' soils are saline and are getting worsened by irrigation water that contains salt. Therefore, the development of rice varieties that could withstand osmotic and ionic salt stress is necessary for sustainable production in the Sahel ecozone

    What climate change means for farmers in Africa: A triptych review middle panel: Introductional matters and consequences of global warming for African farmers

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    Climate change seriously influences the livelihoods of African farmers. It was, therefore, felt useful to make an inventory of what climate change really means for them. In this review in three parts, climate change is approached by dealing with the three sides from which the danger comes: (i) global warming, (ii) increasing climate variability, (iii) more (and possibly more severe) meteorological and climatological extreme events. These are the three panels of this triptych review. Vulnerable communities already suffer. They are, therefore, urgently in need of assistance aimedat building resilience, and at undertaking climate change adaptation  efforts to survive and to maintain their livelihoods. Climate change adaptation projects - especially if implemented in the context of adaptation strategies at the macro level - often mobilize public and private stakeholders, engaging them in the problem-solving process. Scientists have an important role to play in these projects. One of the major  problems in guiding rural change, in a rural response to climate change, is the low formal level of education that most farmers have and for which governments have done very little to upgrade it. Improved climate literacy is needed among farmers and a better trained extension that can guide farmers in further rainfall monitoring and rainfall interpretation. Further agro-ecosystem observations that, with the rainfall distribution, explain yields and yield differences are also needed. While it is relatively easy todefine technical messages that can be communicated, one must look beyond “adaptation to current climate variability“. The basic vulnerability factors of communities must be targeted. One of the problems faced is that experts on climate variability and climate change do not really know what information the grassroots need in the short- and medium-term. However, people assisting vulnerable communities do not know what science generated products are available and how to use them. In this first part of the paper, the consequences of global warming are dealt with at length. Increasing temperatures and changing rainfall patterns get attention first. Other consequences of increasing atmospheric  carbondioxide contents and how they influence agricultural production in Africa are also discussed. Ten text boxes distributed over the three parts illustrate local conditions that must be taken into account to understand the impacts/consequences of climate change for African farmers and how they may cope with them.Key words: African farmers, climate change, vulnerabilitie

    Irrigation development and management in Ghana: Prospects and challenges

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    Agriculture plays a vital role in the national economy but it is predominantly dependent on natural rainfall. Irrigated agriculture on a fairly limited scale is a recent phenomenon and was necessitated largely by the seasonality and unreliability of natural rainfall. The development and management of irrigation, however, has been characterised by difficulties notably weak database, excessive cost, environmental problems and extreme pessimism in some quarters since rainfed agriculture is seen as potentially able to support the present population. Irrigation capacity utilisation on existing schemes is very low and reasons for this situation are put forward, as well as the broad policy objectives needed to promote irrigation development and management. Water management is seen as a serious drawback on existing schemes. It is envisaged that irrigation will be seen in its right perspective as a multidisciplinary activity to ensure the success of schemes. There is the need for running a postgraduate programme in irrigation at the KNUST to enhance the nations efforts at developing and managing irrigation projects successfully

    Boundary Applicability of the Ghana’s Oil Block Fiscal Regimes

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    AbstractAttractiveness of fiscal regime has become more important in oil and gas investment decision than the rather geological prospectivity of the province. The terms and conditions contained in the fiscal system influence the investor’s evaluation of project. As Ghana determines to benefit greatly from the exploitation of the oil and gas resources, a robust fiscal system attractive in all economical and technical conditions needs to be designed. Ghana has recently become one of the frontiers in the oil and gas industry following its commercial discoveries of hydrocarbons in Deepwater Tano-Cape Three Point, the Jubilee field. Ghana’s oil industry is very young and some of the basins are under exploration surveillances waiting for commercial discoveries. Ghana’s Jubilee field uses various terms and conditions in her fiscal arrangement to govern the upstream operations. For continuous realisation of economic benefits to the State as well as the contractor, it is important the applicability of Ghana’s fiscal regime at varying boundary conditions of oil price and field reserves are evaluated. Discounted cash flow economic model which considers the major uncertainties was developed to evaluate the economic implications of the Jubilee field fiscal regime. Different price scenarios and varying field sizes were taken through rigorous sensitivity analysis. It was determined that for all field sizes considered at oil prices above 40/bbl,contractorsNPVsarepositive.Theprojecttakestatisticsareaveragelyaround64 40/bbl, contractor’s NPVs are positive. The project take statistics are averagely around 64% for Government and 36% for contractor under the various scenarios except for oil prices less than 40/bbl where the State’s take statistic is above 80% and contractor’s take below 20%. The State receives Additional Oil Entitlement(AOE) only when the oil price is above $40/bbl and the AOE increases steadily with the oil price for all the various field sizes. In general, the Jubilee field fiscal regime is fairly attractive and flexible and ensures stable shares of economic rents between the State and the contractor as the profitability of the field increases. Keywords: Reserves, Fiscal Regime, Cash Flow, Take Statistics, Net Present Valu

    Amounts of NPK removed from soil in harvested coffee berries as guiding baseline for planning fertilizer requirements of coffee in Ghana

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    Monthly samples of ripened improved robusta coffee berries from compact and large growth forms from three locations, which are representative of the main ecological zones where coffee is grown in Ghana, were taken for 3 years. The pulp and parchment and beans were analysed for N, P and K contents. The amounts of N, P and K removed from the soil in the harvested coffee berries were estimated from the concentrations of the nutrients in the pulp and parchment and beans, and the yield of coffee at each location. The mean NPK contents of the berries were 2.18, 0.08, 2.56 and 2.07, 0.08, 2.52 per cent for compact and large growth forms, respectively. The N and P concentrations in the pulp and parchment were lower than in the bean, while the K content was higher in the pulp and parchment than in the bean across the locations. The N, P and K concentrations of the coffee berries were not significantly different among the growth forms. Coffee berries from suitable and moderately suitable sites removed significantly (P<0.05) higher amounts of N and K than the berries from the marginally suitable site, while the P contents of the berries were significantly (P<0.05) lower than N and K across the locations. Regardless of the coffee growth forms, the demand for N and K may be higher than P. A fertilizer rate of 30 kg N, 1 kg P, and 33 kg K ha-1 may serve as a basis for planning fertilizer requirements of mature coffee in Ghana

    Evaluation of the Performance of Local Cements with Imported Class ‘G’ Cement for Oil Well Cementing Operations in Ghana

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    Portland cement is the most commonly used cement in the oil and gas industry and it accounts for about 99% of all primary cementing operations throughout the world. For Portland cement to qualify as oil well cement, the chemical and physical properties must meet the required standards of the American Petroleum Institute (API). This research evaluates the performance of three locally manufactured cement samples and imported class G cement sample for oil and gas well cementing operations in Ghana. The paper details results of API specification tests and the physical properties of the local cements with the imported class G cement. The results indicated that locally manufactured cements have the potential to be used for cementing oil and gas wells. However, further tests should be conducted to ascertain their stability under High Pressure, High Temperature (HPHT) conditions.Keywords: Compressive strength, Free fluid, Portland cement, Rheology, Thickening tim
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