Samuel T. Partey

Toward climate-smart agriculture in West Africa: a review of climate change impacts, adaptation strategies and policy developments for the livestock, fishery and crop production sectors

Many projections of the impact of climate change on the crop, livestock and fishery production sectors of African agriculture are reported in the literature. However, they may be arguably too general to understand the magnitude of impact and to inform adaptation strategies and policy development efforts that are tailored to promoting climate-smart agriculture in the West African region alone. This paper was synthesized from several scholarly literature and aimed at providing up-to-date information on climate change impacts, adaptation strategies, policies and institutional mechanisms that each agriculture subsector had put in place in dealing with climate change and its related issues in West Africa. For each subsector (crop, fishery and livestock), the current status, climate change impacts, mitigation and adaption strategies have been analyzed. In addition, we reviewed recent policy initiatives in the region that foster the development and adoption of climate-smart agricultural options to improve resilience of farming systems and livelihoods of smallholder farmers to climate change risks. From community to national and regional levels, various strategies and policies are also being taken to guide actions and investment for climate-smart agriculture in West Africa.

Improving maize residue use in soil fertility restoration by mixing with residues of low C-to-N ratio: effects on C and N mineralization and soil microbial biomass

The application of organic residues with wide C-to-N ratio on soils is known to cause nitrogen immobilization unless applied with nitrogen fertilizer. Considering that fertilizer usage is limited in low input agricultural systems in Africa. we determined whether it was possible to alleviate N immobilization of Zea mays (maize) by applying together with Tithonia diversifolia or Vicia faba green manure with low C-to-N ratio. The effect of sole Z. mays application on soil microbial biomass and carbon mineralization were also compared with when mixed with T. diversifolia or V. faba. The objectives were achieved using laboratory incubation experiments conducted over 84 days. As expected. the application of sole Z. mays residues resulted in an initial net N immobilization that lasted for 28 days. Relative to sole Z. mays. the application of Z. mays with either V. faba or T. diversifolia increased N mineralization by 58% and 55% respectively. It was also evident. that in comparison with sole Z. mays. soil microbial biomass and C mineralization were significantly higher in soils that received residues of V. faba and T. diversifolia either alone or in combination with Z. mays. The study showed that V. faba and T. diversifolia either alone or in combination with Z. mays residues had relatively high N concentration and narrow C-to-N ratio. which accounted for the increased N mineralization and improved microbial biomass and C mineralization. We inferred from the results of our study that N supplies from V. faba and T. diversifolia could be substantial in alleviating delayed decomposition and N immobilization of Z. mays residues.

Biochar use in a legume–rice rotation system: effects on soil fertility and crop performance

The aim of this study was to determine whether by applying biochar, it is possible to augment the beneficial effects of legume–crop rotation systems on soil fertility and crop performance. Repeated experiments were established in 2012 and 2013 in South-western Benin using a split-split plot design. Two legumes, Mucuna pruriens (mucuna) and Vigna unguiculata (cowpea), were planted for 42 days on biochar-amended and unamended plots and subsequently cut and applied as mulch 5 days before planting rice. Rice plants were either fertilized or not using a fertilizer rate of 60, 30, and 30 kg ha−1 of N, P2O5, and K2O, respectively. The results showed that the application of legume green manures and fertilizer, either singly or in combination, improved soil nutrient availability, CEC, shoot yield, and grain yield of rice on both biochar-amended and unamended plots. However, the effect was significantly (p < 0.05) greater on biochar-amended plots. The mean grain yield for all cropping seasons was 1.8 t ha−1 for biochar-amended plots and 1.3 t ha−1 for unamended plots. The greater grain yield of rice on biochar-amended plots was associated with improved soil fertility and increased N uptake.

Agronomic Potentials of Rarely Used Agroforestry Species for Smallholder Agriculture in Sub-Saharan Africa: An Exploratory Study

Despite significant evidence that green manures from agroforestry species can improve soil fertility, green biomasses from many agroforestry species have not been sufficiently explored. In this study, we determined the suitability of green manures of Tithonia diversifolia, Gliricidia sepium, and Senna spectabilis for smallholder agriculture in Africa. Field trials were established to compare them with mineral fertilizer. The results showed that green manures of the three species were of high quality based on their macronutrient compositions. The effect of the green manures (particularly Tithonia) on both the biomass and fruit yield of okro were comparable and in some cases greater than fertilizer treatments. Total yield response in Tithonia treatment was 61% and 20% greater than the control and fertilizer treatments, respectively. In addition, the okro plants recovered a greater percentage of the nitrogen (N), phosphorus (P), and potassium (K) added as green manure compared to fertilizer-treated plots, which received the greatest N, P, and K inputs.

An assessment of mobile phone-based dissemination of weather and market information in the Upper West Region of Ghana

BackgroundThe rapid growth of mobile phones in Ghana has opened up the possibility of delivering timely and useful weather and market information to farmers at costs lower than traditional agricultural extension services. In this paper, we assess the usefulness, constraints, and factors likely to influence farmers’ decisions to patronize mobile phone-based weather and market information.MethodsWe rely on primary data from 310 farmers in the Upper West Region, an understudied part of Ghana. We subject the data to three types of analysis. First, we model farmers’ decision to patronize mobile phone-based weather and market information by estimating a binary logit model. Second, we use descriptive statistics and hypothesis testing to analyse the level of usefulness of mobile phone-based weather and market information. We disaggregate the analysis by sex, income status, and age group. Finally, we use qualitative analysis to summarize the constraints associated with the utilization of mobile phone-based weather and market information.ResultsWe find that contact with agricultural extension agents and farmer-to-farmer extension services significantly influences farmers’ decision to patronize mobile phone-based weather and market information. Regardless of sex, income status, and age group, farmers generally rate mobile phone-based weather and market information as very useful. We identify inexact information, complex text messages, information that are too costly to implement, and poor infrastructure as the constraints to the utilization of mobile phone-based weather and market information.ConclusionIn order to improve the utilization of mobile phone-based weather and market information, disseminators of mobile phone-based information such as Esoko should constantly update and provide client-specific information. Improvements in mobile phone networks and related services will enhance the utilization of mobile phone-based weather and market information.

Markets and climate are driving rapid change in farming practices in Savannah West Africa

Agricultural practices have constantly changed in West Africa, and understanding the factors that have driven the changes may help guide strategies to promote sustainable agriculture in the region. To contribute to such efforts, this paper analyzes drivers of change in farming practices in the region using data obtained from surveys of 700 farming households in five countries (Burkina Faso, Ghana, Mali, Niger and Senegal). The results showed that farmers have adopted various practices in response to the challenges they have faced during the last decade. A series of logit models showed that most changes farmers made to their practices are undertaken for multiple reasons. Land use and management changes including expanding farmed areas and using mineral fertilization and manure are positively related to perceived changes in the climate, such as more erratic rainfall. Planting new varieties, introducing new crops, crop rotation, expanding farmed area and using pesticides are positively associated with new market opportunities. Farm practices that require relatively high financial investment such as use of pesticides, drought-tolerant varieties and improved seeds were positively associated with the provision of technical and financial support for farmers through development projects and policies. Changes in markets and climate are both helping to promote needed changes in farming practices in West Africa. Therefore, policies that foster the development of markets for agricultural products, and improved weather- and climate-related information linked to knowledge of appropriate agricultural innovations in different environments are needed.

Potentials of Bamboo-Based Agroforestry for Sustainable Development in Sub-Saharan Africa: A Review

There is widespread assertion among scientists, government and development experts that bamboo agroforestry could contribute to sustainable rural development in Sub-Saharan Africa (SSA). However, there are limited available data to verify the suitability of the system in the region. In addition, the current state of knowledge and adoption of agroforestry in SSA offers very little guidance as to which type of agroforestry systems bamboo could be integrated. Here, we reviewed the potential socioeconomic and environmental benefits of bamboo agroforestry and accentuate implications on sustainable rural development in SSA. In addition, we analysed potential research areas that could be intensified, so that future developments and scaling-up of bamboo agroforestry can be rooted in robust scientific findings rather than the intuitions of governments and development actors.

Gender and climate risk management: evidence of climate information use in Ghana

The gender perspective of climate information use is not well studied although necessary for developing gender-responsive climate information services (CIS). This study determined how CIS use by men and women farmers may be influenced by their perceptions about climate change (CC), farm activities, and demography. The study was carried out at the Lawra-Jirapa Districts of the Upper West Region of Ghana where downscaled seasonal forecast information through mobile phone technologies (Esoko platform) had been disseminated to farmers since 2011. Data was collected from semi-structured questionnaire interviews involving 900 farmers (50.2% women and 49.8% men) and four 20-member focus group discussions. The study confirmed 85.2% (representing 767) farmers were aware of climate change and its implications for their agriculture and other livelihood activities. Men and women had similar perceptions about climate change, perceived by the majority as increased strong winds, higher temperatures, increased frequency of drought, increased rainfall variability and increased flooding. Among other factors, it was evident that use of CIS may be influenced by gender. Men were found to be particularly responsive in adopting CIS use for climate risk mitigation. This was attributed to their ability to easily access and use telephone devices compared with women. The study revealed that unlike women, men were able to access more financial resources and had control of household income which allowed them to purchase mobile phones. Women generally accessed their husbands’ mobile phones. Despite differences in access to CIS, the study showed both men and women found it beneficial for strategic farm decision-making such as when to begin land preparation, when to plant, and which crop to select. In addition, both men and women were found to face similar constrains (such as poor network connectivity and limited of training), to accessing and using CIS through the Esoko platform. The study recommends the need to explore different CIS dissemination channels and design CIS that meet gender-specific needs.

N availability, soil microbial biomass and β-glucosidase activity as influenced by the decomposition of nine plant residues during soil fertility improvement in Ghana

This study wasconducted to determine how the litter quality and decomposition of nine species (Acacia auriculiformis, Albizia zygia, Azadiractha indica,Baphia nitida, Gliricidia sepium, Leucaena leucocephala, Tithonia diversifolia, Senna spectabilis and Zea mays) influence soil N availability, microbial biomass and β-glucosidase activity during soil fertility improvement. The results on plant residue chemistry showed significant differences among species with N concentration ranging from 12.2 g kg−1 in Z. mays to 39.2 g kg−1 in B. nitida.C/N ratio was greatest in Z. mays (34.4) while lignin and polyphenol concentrations were greatest in A. auriculiformis. The highest decomposition rate (0.251% day−1) occurred in T. diversifolia and least in A. auriculiformis, A. zygia, B. nitida and Z. mays with half-lives of between 28 – 56 days. Similar to the results on decomposition, between 80 to 89% of N, P, K, Ca and Mg were released from T. diversifolia within 7 days compared with more than 70% retention in A. auriculiformis, B. nitida and Z. mays. Moreover, the half-lives of decomposition and nutrient release of G. sepium, L. leucocephala, A. indica and S. spectabiliswere within 14 days. Mineral N, soil microbial biomass and β-glucosidase activities increased in all treatments with T. diversifolia recording the greatest effect. While N mineralization occurred in all species throughout the experiment, an initial N immobilization was recorded in A. zygia, B. nitida, A. auriculiformis and Z. mays treatments for up to 14 days. Further, the results showed the decomposition, nutrient release rates, mineral N, soil microbial biomass and β-glucosidase activities were dependent on litter quality. Phosphorus, lignin, lignin/N ratio and (lignin + polyphenol)/N ratio were most influential based on significant (p = 0.05) results.