Sustainable rice production in Sierra Leone faces serious constraints due to soil acidity, low cation exchange capacity, low nutrient contents accelerated mineralization of soil organic matter and soil loss by erosion (particularly on the uplands). One possible approach to addressing the soil constraints to rice production both on uplands and lowlands of Sierra Leone is the recycling of rice residues through biochar production and application to soils. A pot experiment was conducted to investigate the effects of application of biochar from rice residues on (i) soil physicochemical properties and (ii) the early growth characteristics of two rice varieties, NERICA L19 and ROK3. The experiment was arranged in a completely randomized design (CRD) with two biochar levels (0 and 15 g/kg soil) and two rice varieties in three replications. For the biochar treated soils (+biochar), 75 g rice straw biochar was applied to 5 kg air-dry soil (15 kg biochar/kg soil), mixed thoroughly and placed into perforated black polythene bags. Seeds of two rice varieties, NERICA L19 and ROK3 were planted on the treated and untreated soils for eight weeks. Application of biochar improved available phosphorus, exchangeable cations and cation exchange capacity in biochar treated soils compared to the control soil without biochar. Plant height, tiller number, and dry biomass weight of both rice varieties grown in soils amended with rice straw biochar were significantly higher than those on untreated soils. The most remarkable increase in plant growth characteristics as a result of biochar addition to soil was reflected in the biomass yield and tiller numbers. Dry shoot biomass for ROK3 rice variety varied significantly from a mean of 3.5 g (control) to 26.2 g (+biochar) while tiller numbers significantly varied from 10 (control) to 29.6 (+biochar). Similarly, for NERICA L19 rice variety, dry shoot biomass increased significantly from 4.5 g (control) to 22.7 g (+biochar) while tiller numbers increased significantly from a mean of 12.3 (control) to 30 (+biochar). Thus converting rice residues to biochar and applying to soil holds

With the world population hitting 8 billion and the global climate becoming more erratic with pronounced droughts, floods, water shortages and storage depletions, the need for optimal soil and water conditions for high crop productivity and food security has become ever more urgent. There is a growing effort towards enhancing water storage in the root‐zone soil layer (as a rainwater‐harvesting strategy) to increase crop productivity. This study analysed the effects of biochar and deficit irrigation on rice productivity under greenhouse conditions. Grain yield, plant height, tiller number and biomass yield under 0% biochar (B1) were respectively 13.6, 6.4, 27.4 and 3.0% higher for moderate deficit irrigation (I2) than for flood irrigation (I1). Also in terms of tiller number, I2 performed better than I1 by 45.8 and 69.2% under B2 (4% biochar) and B4 (16% biochar), respectively. While for biochar the highest crop productivity was under B2, this changed vastly under the combined effects of irrigation and biochar. This suggested that crop productivity was as much dependent on irrigation as on biochar treatment. The variations in productivity could provide farmers with the choice of treatments or treatment combinations that are best suitable for their local agro‐edaphic, hydroclimatic and socio‐economic conditions. Copyright © 2017 John Wiley & Sons, Ltd.

Farms less than two hectares constitute most farm holdings in Africa. Most of these farms are operated by rural smallholder farmers who are dependent on agriculture for their economic livelihoods. However, they are constrained by lack of capital assets that would enable them to increase agricultural productivity, food security and income. Despite these challenges, smallholders contribute significantly to the rural economy, and play a significant role in natural resource conservation. Therefore, they represent a critical population to include in poverty reduction efforts. Recent initiatives by African leaders aim to increase public expenditures on agriculture in order to spur economic development, position smallholders to play a significant role in regional growth. To understand the relevance of smallholder farming to Africa's development agenda, this paper reviews the body of knowledge on smallholder farmers, the constraints and opportunities they face, and their use of practices which embody the tenets of ecological and climate-smart agriculture despite little public investment in this area. This paper recognizes the role of smallholder farmers and concludes that smallholder agriculture will be a driver of economic growth and development in Africa. In order to achieve this, adequate investment should be focused on eliminating the challenges faced by smallholder farmers.

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Abstract:Although there has been an increased focus on the use of biochar for improving soil fertility and mitigating climate change, some biochars have been reported to contain substances that affect germination and seedling growth negatively. It is therefore necessary to evaluate any biochar material for its effect on seed germination before large scale applications. This study was therefore undertaken to assess the effects of (i) biochar derived from maize stover on maize seed germination and (ii) biochar derived from rice straw on rice seed germination. Seeds of maize (Zea maize L.) and rice (Oryza sativa) were sown separately to soils treated with increasing levels of biochar derived from maize and rice residues respectively. The experiment was conducted using a completely randomized design involving five biochar treatments: 0 g (control), 1.25g, 2.50g, 3.75g and 5.00g each mixed with 300g of a fine sandy loam soil in Sierra Leone. Results of the germination test showed that most of the maize seeds (>80%) germinated by day3 and there was no significant difference in the number of maize seeds germinated on day 7. On the other hand, few rice seeds germinated on day3 (35%) and was significantly greater than the number of the rice seeds (>90%) germinated on day 7. However, even though the number of maize or rice seeds germinated on biochar treated soils was higher than the control, the difference was not significant. Also, no significant differences in root lengths were observed between the control and biochar treatments at day 7 for both plants. However, maize shoot length differed significantly from the control whereas rice shoot length did not. The results showed that sowing seeds of maize and rice on soils treated with biochar derived from their crop residues had no adverse effect on germination. These findings hold great potential for improved and sustainable maize and rice cultivation in Sierra Leone.

Lassa Fever is endemic to the eastern region of Sierra Leone. It is a haemorrhagic disease that is often transmitted from rats to humans and then human to humans. Ecological disturbances such as changes in land use involving conversion of natural ecosystems to agriculture, mining or for urban expansion are reported to bring humans into close contact with animals such as the Mastomys rat that carries the Lassa Fever virus thereby posing health problems.The nature and extent of such ecological disturbances or land use changes within areas known to be endemic to Lassa Fever are not clearly understood from a research context in Sierra Leone. This study was therefore undertaken to identify the pattern of changes in land use and cropping practices and their potential to bring humans into close interactions with the Mastomys rat that is the host for the Lassa Fever virus. Four communities were chosen for the study, two rural (Lalehun and Majihun) and two urban (Lambayama section in Kenema City and Largo Square section in Segbwema Town). Different vegetation and land use/cropping practices were identified and observations were made on the pattern of changes at different times in the cropping year. There were four common vegetation and cropping practices found in all communities: upland rice intercropping, old fallow, young fallow, and swamp rice cultivation. The study revealed the variations in land use patterns and cropping practices between urban and rural settlements. Agro-forestry practices such as perennial cash crops cacao and rubber plantations were more common in rural communities. The study also revealed that while fallow vegetation persisted in rural areas there had been expansion of settlements into old fallow vegetation indicating a greater threat to the persistence of natural ecosystem in urban than in rural settlements. These disturbances resulted in habitat fragmentation and increased the likelihood of contact between humans and animal species (e.g. Mastomys * Corresponding author.A. Kamara et al. 451 rat) associated with various habitats.

Slash-and-burn agriculture is the common practice for upland rice intercropping system in Sierra Leone and it has been blamed for the loss of forest vegetation across the country. Shortening of the fallow period in the Eastern region of Sierra Leone has implications on agricultural food production and the persistence of the remaining tropical rainforest. This study was therefore undertaken to assess: 1) the extent of reduction of the fallow period in the Nongowa Chiefdom of Kenema District; 2) the causes of reduction in the fallow period; 3) farmers' perception of the relevance of fallow period and the implications of reduction of fallow period on crop production. The study revealed a drastic reduction of the fallow period in the chiefdom with a mean of 3.8 years which falls far below the country mean fallow period of 8.8 years as estimated by FAO. Farmers pointed out that the reduction of the fallow period was as a result of land scarcity due to competing land uses such as large scale commercial agriculture, logging, mining, charcoal burning and expansion of settlements. Farmers agreed that a fallow period of at least 10 years is necessary for upland rice production. Farmers were aware of the impact of reduction of the fallow period on upland rice production and were able to estimate rice yields based on the age of the fallow. Also, farmers have attempted to adapt to the constraints posed by shorter fallow periods by selection of rice varieties to suit the length of the fallow periods.

Crop residues such as maize and rice are important sources of nutrients and their restitution to the soil is an important residue management strategy for maintaining or improving soil and crop productivity. However, most maize and rice farmers in Sierra Leone burn crop residues during land preparation thereby depriving the soil of this vital resource. An alternative approach is the recycling of crop residues through biochar production. This study was therefore carried out to assess the effects of (i) maize stover biochar on the early growth of maize and (ii) rice straw biochar on the early growth of rice. In this study, biochar (0g, 12.5g, 25.0g, 37.5g and 50.0g) was mixed with 3kg of soil (fine sandy loam) and placed in perforated black polythene bags. Maize or rice seeds (3 per pot) were planted to 2cm depth and later thinned to one plant per pot. All pots were placed in the open under direct sunlight and rainfall. No supplemental irrigation was done since there was sufficient rainfall to supply the required moisture. The experiment was laid in completely randomized design with five treatments and three replications. After four weeks, the experiment was terminated. Mean plant height, stem girth, fresh-and dry-shoot weights of both maize and rice plants generally increased significantly (p<0.05) relative to the control at biochar applications ≥8.3g/kg soil. The results showed that growing maize and rice on soils treated with biochar derived from their residues (maize stover and rice straw respectively) has the potential to improve crop production. Confirmatory field trials and costs/benefits analysis of converting rice and maize residues to biochar will serve as a good guide for policy makers and end-users (farmers) for increased productivity of maize and rice in Sierra Leone.