Labor requirements and profitability of alternative soil fertility replenishment technologies in Zambia

Low soil fertility is a major concern in agricultural productivity and development policy discourse in sub-saharan Africa. The problem is exacerbated by government withdrawal from fertilizer input markets and the inability of private sector operators to fill the gap. This warranted a search for other nutrient sources to supplement chemical fertilizers. Based on field data collected in Zambia, this study assessed the labor inputs implications of “improved tree fallows”, continuous maize cropping with and without mineral fertilizer and, evaluated the financial profitability of the different land use systems. Results show that agroforestry-based land use systems are more profitable (NPV between $233 and$309 per ha) than farmers’ practice of continuous maize production without external fertilization ($130/ha) but, they are less profitable than mineral fertilizer ($499). When the effects of the 50% government subsidy on fertilizers are taken into account, the differences in the profitability of fertilizers over improved tree fallows falls from 61% to 13%. The returns per person labor-day is $3.20 for fertilizer and$2.50, $2.40, and$1.90 respectively, for the three agroforestry options evaluated and only $1.10 for unfertilized maize. These returns compare with a daily agricultural wage of$0.50 in the study area. Key determinants of financial attractiveness and by extension, potential adoptability of the land use systems were identified. Given the low rate (20%) of farmers in Zambia who have access to fertilizers, there is a large niche to integrate other soil nutrient replenishing options with fertilizer to improve food security and reduce poverty among resource-poor smallholder farmers in Africa.Agroforestry, improved tree fallows, financial analysis, Production economics, Southern Africa, Sustainable agriculture, Agricultural and Food Policy, Community/Rural/Urban Development, Consumer/Household Economics, Environmental Economics and Policy, Farm Management, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Land Economics/Use, Production Economics, Research and Development/Tech Change/Emerging Technologies,

The Role of Food from Natural Resources in Reducing Vulnerability to Poverty: A Case Study from Zimbabwe

Vulnerability to poverty is a major problem in the rural areas of Sub Saharan Africa. Rural Households are confronted with various covariate and idiosyncratic shocks and are often severely constrained in coping with such events. They frequently resort to food from natural resources such as indigenous fruits during times of crisis. The availability of such food sources is increasingly at risk due to deforestation and biodiversity loss. The objective of this paper is to quantify the contribution of indigenous fruit trees towards reducing vulnerability to food insecurity and poverty. The methodology used is a multi-period stochastic household income model. The data were collected in a case study in Zimbabwe using detailed monthly income and expenditure records of a sample of 39 rural households in two areas. The two regions differ in their agricultural system. In one area horticulture, off-farm activities and exotic fruits are a major source of income while in the other area indigenous fruits are a more important source of income. This paper concentrates on the latter area. Model calculations show that rural households in Zimbabwe are highly vulnerable to seasonal fluctuations in income and therefore a critical period where households run high risk of being food insecure can be identified. While indigenous fruits, as a low cost 1 International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya, [email protected] (for merly 2 & 3). 2 Development and Agricultural Economics, Faculty of Econo mics and Business Administration, Hannover University, Germany. 3 World Agrofore stry Centre (ICRAF), Lilongwe, Malawi. natural resource, can facilitate income-smoothing, the role of other sources of income must not be neglected. The paper concludes that diversified season-specific income generating portfolios must be designed of which indigenous fruit trees have a role to play.Vulnerability, poverty, food security, seasonal fluctuations, wild food resources, Zimbabwe, Food Security and Poverty,

Community-based O&M challenges

The Volta Rural Water Supply and Sanitation Project is a 10 year (two phased) DANIDA supported project in the Volta Region of Ghana. It is jointly implemented by the Community Water and Sanitation Division (CWSD) of Ghana Water and Sewerage Corporation responsible for rural water supply and sanitation and COWI a Danish Engineering Consulting Company. The project is aimed at raising the standard of living of the rural population of the region through the provision of potable water, improved affordable toilets and hygiene education. The first phase of the project ended in August 1997. The project has its main focus of facilitating a sustainable community-based operation and maintenance (O&M) regime in line with the government’s water and sanitation sector strategy. In order to achieve this, the project since its inception in March 1993 has adopted the partnership approach to facilitate project implementation. It follows that the community structure with the support from the private and public sectors will have to develop mechanisms for O&M. The writer examines the project’s partnership approach and the lessons so far in community participation in the management process

Anti-Malarial Activity and Toxicological Effect of Combined Corymbia Citriodora, Maytenus Senegalensis and Warbugia Ugandensis as Used in Traditional Medicine in Kenya

Malaria is majorly caused by Plasmodium falciparum resulting in thousands of deaths every year. In Africa, it is a key contributor to the disease burden notable in the disability adjusted life years (DALYs). About 243 million individuals are at a risk of contracting the disease and a higher rate of deaths are observed in children under the age of five. Conventional drugs are available at a subsidized rate but the rising problem is the resistance of the plasmodium parasite to these drugs. Hence, there is an urgent need for the development of new and alternative therapeutics for treatment of malaria. In some regions in Kenya, parts of locally available plants are harvested and used for treating malaria. It is estimated that locally, 30% of the population relies on traditional medicine for treating various ailments due to the lack of infrastructure and accessible medical facilities especially in the rural areas. Warbugia ugandensis, Maytenus senegalensis and Corymbia citriodora are amongst the plants used in herbal medicine for the treatment of malaria. However, their combinatorial antimalarial efficacy and safety is yet to be determined hence the aim of this study. The plants were harvested from their natural habitats and transported to the Centre of Traditional Medicine and Drug Research (CTMDR) at the Kenya Medical Research Institute (KEMRI), Nairobi. Antimalarial properties of single and combined extracts were analyzed against Plasmodium berghei in vivo. Cytotoxic properties of the plants were carried out against the vero cell-lines in vitro by the MTT assay. Acute oral toxicity was conducted according to the OECD protocol. Effective concentration (ED50), cytotoxicity concentration (CC50) and median lethal dose (LD50) were derived. The result indicated that the combination of M. senegalensis: W. ugandensis (1:1) had the most antimalarial activity at ED50 of 1.05mg/kg whereas among the single plants W. ugandensis had the highest antimalarial activity (ED50 of 3.3mg/kg). The combinations of C. citriodora: M. senegalensis: W. ugandensis (1:1:1), C. citriodora: M. senegalensis: W. ugandensis (1:0.5:1) and C. citriodora: M. senegalensis: W. ugandensis (0.5:1:0.5) showed cytotoxicity concentration (CC50) of 101.47±3.17 µg/ml, 213.55±3.47 µg/ml and 575.80±31.40 µg/ml respectively. All the plants combinations showed no cytotoxic effects. The synergistic antimalarial properties of combined C. citriodora: M. senegalensis, C. citriodora: W. ugandensis and M. senegalensis: W. ugandensis were confirmed as the extracts showed SFIC indexes of 0.67, 0.83 and 0.28 respectively. All the plant extracts demonstrated LD50 above 2000 mg/kg with no adverse effects hence recognized as safe. This study confirms the safety and antimalarial activities of these plants and justify their use in herbal medicine practices. The results of this study sets the precedence for the development of an antimalarial herbal formulation that is less toxic and more affordable.Keywords: Anti-Malarial Activity, Toxicological Effect, Traditional Medicine DOI: 10.7176/JNSR/12-22-04 Publication date: November 30th 202

Simulation Model for a Frequency-Selective Land Mobile Satellite Communication Channel

This paper investigates a three-state simulation model for a frequency-selective land mobile satellite communication (LMSC) channel. Aside from ionospheric effects, the propagation channels for LMSC systems are also characterized by wideband effects due to multipath fading which makes the channels time-variant and exhibit frequency-selective distortion. Hence, an adequate knowledge and modelling of the propagation channel is necessary for the design and performance evaluation of the LMSC systems. A three-state simulation model for a frequency-selective LMSC channel, which is a combination of Rayleigh, Rician and Loo fading processes, is developed. The propagation characteristics of the proposed LMSC channel model are presented, and comparisons are made with the Rayleigh, Rician and Loo fading channels using bit error rate (BER) as the figure of merit. The simulation results show that the degree of fading experienced by the LMSC link depends on the length of time the mobile terminal is in a particular state or location, depending on the assumed probability of occurrence of each fading process; and it is observed from the BER results that the propagation impairment of the LMSC fading channel is relatively lower than that of Rayleigh and Loo fading channels but higher than the Rician fading channel. Keywords: mobile, multipath fading, propagation channel, satellite communication, wideband.

Performance of RS and BCH Codes over Correlated Rayleigh Fading Channel using QAM Modulation Technique

The quest for a reliable reception of the replica of a transmitted signal over wireless medium has become very important in the transmission and reception of information. In order to mitigate the effect of the degradation of the transmitted signal, error correction techniques are employed to reliably recover the erroneous bits inherent especially when the channel is in deep fading. In this paper, the performance of Reed Solomon (RS) and Bose-Chaudhuri-Hochquenghem (BCH) codes over correlated Rayleigh fading is presented. This work also investigated the effect of error correction code in the variation of the modulation order of the QAM. The simulation was carried out by encoding randomly generated data using both RS and BCH codes and then modulated by varying the modulation order of the quadrature amplitude modulation before transmitted over a correlated Rayleigh distributed channel. At the receiver, the received signal was demodulated and decoded. The bits in error received were detected and corrected to retrieve back the original transmitted signal. The system was evaluated in bit error rate and the result showed that BCH code performs better for higher modulation order. Keywords: Correlated channel, Rayleigh fading, M-QAM, RS code, BCH code

Wheat straw bio-refining. Part II: Optimization of the microwave radiation with sulphuric acid pre-treatment and its enzymatic hydrolysis for fermentable sugars

Background: The potential of microwave-assisted heating for enhancing the alkaline pretreatment of lignocellulosic waste is highlighted in this work.Objective: To maximize separation of fermentable sugars from wheat straw.Methods: Wheat straw hydrolysis assisted by microwave was carried out by setting up a statistical experimental design method and further investigating the main process parameters, namely: temperature (°C), microwave power (W), NaOH concentration (M) and wheat straw pre-treatment time (min) towards maximization of fermentable sugars extraction from wheat straw. The reducing sugars yield (response) of the alkaline pre-treated and microwaved wheat straw in lab scale provided data for building a predictive model which reflected interactions, significance and impact of the process parameters (factors) on the wheat straw hydrolysis yield.Results: SEM and FTIR images of untreated and alkaline pre-treated wheat straw were studied for investigating the morphological changes of wheat straw surface quality and structure resulting from the microwave and/or alkaline pre-treatment. In addition reducing sugars yield of 87%wt. from wheat straw pre-treated at 180°C, 550W microwave power, 0.65M of NaOH for 25min was achieved. This result was significantly higher compared to the one from the straw which was only hydrolysed enzymatically (30 %wt).Conclusion: It was found that shorter pre-treatment times were obtained at higher temperatures, alkali concentration and moderate microwave power levels. The results obtained were further optimized and indicated that the microwave-assisted alkaline pre-treatment of wheat straw technique is an attractive pre-treatment method which reduces the wheat straw pre-treatment time and enhances the hydrolysis yield

Development of a Polythene Recycling Machine from Locally Sourced Materials

Non-biodegradable polythene and nylon wastes constitute a nuisance in all the urban areas in Nigeria. The paper presents the design and manufacture of a waste-recycling machine to convert these waste materials to reusable materials. The machine uses designed to use fixed and rotary blades for slitting the loaded wastes. The rotary blades are rotated by a single phase, high speed electric motor and the friction generated provides the heat required to soften the waste charges. The recycling machine produces an average of 35kg of small flakes of recycled waste per hour at a machine speed of 2880 rpm. Keywords: Polythene, Nylon, Biodegradable, Waste Recycling, Electric Moto

Farm Forestry Development in Kenya: A Comparative Analysis of Household Economic Land Use Decisions in UasinGishu and Vihiga Counties

Tree growing on farms in Kenya is an important land use that has evolved over the last 100 years into multi-billion subsistence and commercial oriented enterprises.  The smallholder farms in medium and high potential areas are facing serious shortage of quality farming land that has created severe competition among various competing land uses mostly agriculture and farm forestry. Therefore the economic competitiveness of farm forestry as a land use is assumed to be proportional to the size of household land allocated to its use. Understanding household decisions making in allocation of land to competing land uses has increasingly become an important subject to resource economists and policy makers. Therefore a study was undertaken in 2011/2012 to evaluate the socioeconomic decisions making in relations to farm forestry in two counties in high potential agricultural areas of western Kenya. The two counties were selected for the study differed settlement in history, agricultural land use, farm forestry development and demographic characteristics. Uasin Gishu represents the recently settled former European settler farms and Vihiga to represents the former African Reserves. The study was based on range of models such as spatial land use concepts, integrated land use decision making and land use efficiency criterion to underpin the household production function.  260 households were surveyed using systematic sampling methods with questionnaires being administered randomly to households in locations within selected divisions.  The main data extracted from the standard questionnaire were household structure, ratio of land used for cropping, grazing and farm forestry, product output, prices, market information, marketing procedures and distribution of trees by species.  Data was analysed by use of OLS regression models to generate key farm forestry decision making parameters.  The results show that household land size had strong influence on farm forestry decisions irrespective of household’s production strategy.  Farm forestry incomes proved to be an importance driving force in decisions to plant trees thus supporting the importance of economic objectives on household land use decisions. A farm forestry income was stronger in areas where markets and marketing infrastructure were better developed.  The density of planted trees increased with decreasing land size attested the strength of subsistence and commercial dimension of trees within an agricultural landscape. The study points out some policy lessons for development of farm forestry in developing countries like Kenya that include putting in place policies and regulations that attract, expand and sustain farm forestry product demand and infrastructure that improve marketing efficiency and thus better income to farmers from sale of trees. Keywords: Farm forestry, Land use, Household decision makin

A Review Farm Forestry Evolution for the Last 100 Years in Kenya: A Look at Some Key Phases and Driving Factors

The study reviews the evolution of tree growing in Kenya from pre-colonial through colonial to the present day in order to understand some factors that have influenced such developments. The study is based on desktop literatures reviews of various studies done in the country over the years and the authors’ experiences. The study indicates that forest resources management during pre-colonial period were based on individual communities’traditional structures that ensured that its members had abundant supplies of land and resources to support their socioeconomic activities. Forestlands were viewed as reserves for future agricultural expansion depending on community population growth and settlement patterns. In 1895 the country was declared British Protectorate that heralded the entry of colonial settlers that drastically changed land ownership through displacement and concentration of indigenous populations. Improved health services led to drastic population growths that further shrunk available productive land and forest resources to levels that could not adequately accommodate traditional land uses. The resultant was seriousland degradation in Africa reserves that prompted the Colonial Government to initiate agricultural and land use transformations that included afforestation in highly populated for environmental conservation, boundary marking and supply of tree products. Another parallel development was forest reservation and expansion of public plantation by Forest Department that involved planting of fast growing exotic species such as Eucalyptus, Pines and Cypress among others that diffused to neighbouring farms, missionary centres, schools and emerging elite Africans for amenity and social status. The emergence of Acacia mearnsii as a cash crop for African farmers in Central and western Kenya in 1930s was another development that enhanced adoption of tree growing on farms in the country. After independence in 1963 more policies and strategies to promote tree growing on former settler farms and African reserves for environmental conservation and subsistence needs implemented.  The last chapter of the farm forestry evolution was the commercialization of farm forestry operations due increased demand for various forest products beyond the capacity of public forests. The key markets niches mostly for firewood in tea processing, transmission poles manufacturing, charcoal and sawnwood for rural and urban markets were lucrative enough to motivate millions of smallholder farmers to expand their farm forestry investments. The markets based incentives to meet the growing demand for various products has transformed farm forestry in Kenya into multibillion sector enterprises that competes with public and private plantations products in local markets. The lessons learnt in Kenya case is the multiple factors that have shaped farm forestry development over the last 100 years and the critical role played by market related factors that enabled smallholder tree growers to enter into lucrative short rotation wood product markets. Keywords: Farm forestry evolution, phases, driving factor