Climate-smart Agriculture Research Articles

Effects of Climate-Smart Agriculture on Smallholder Farmers in the Eastern Province of Zambia

Climate change is one of the distressful environmental challenges the world has been grappling with in recent times as it affects crop production, among other economic activities. The Eastern Province of Zambia has not been spared by crop failure resulting from climate-induced effects. As a result, the Zambia Integrated Forest Landscape Project (ZIFLP) implemented climate-smart agriculture (CSA) in the Eastern Province, from the first quarter of 2018 to the first quarter of 2024, which aimed to improve smallholder farmers' resilience to the effects of climate change on crop productivity. However, the effects of the CSA techniques on crop productivity were scientifically unclear. Therefore, this study used a mixed-methods approach to investigate the effects of CSA on crop productivity of the 106 smallholder farmers as questionnaire respondents and five District Agriculture Co-ordinators as key informants for interviews. The results revealed that all the respondents (100%) were aware of CSA in their communities, and about two-fifths (42%) of them, who formed the majority, practised crop rotation the most. Almost all the respondents (96%) viewed CSA as an important agricultural intervention in their communities in light of the adverse effects of climate change. Two-thirds (66%) of the respondents, who were the majority, acknowledge that the CSA techniques increased crop yield. The maize crop tonnage <i>Mean (M = 7.70)</i> after the respondents’ implementation of CSA was statistically significantly higher than the maize crop tonnage <i>Mean (M = 3.82)</i> before the respondents implemented CSA, signifying that the respondents produced more tonnage of maize crops after they implemented CSA than before. The study concludes that CSA in the Eastern Province of Zambia is an intervention through which smallholder farmers were helped to enhance their crop productivity in light of the devastating effects of climate change. Therefore, the study recommends continuity of financial and technical support of CSA by the Zambian government or cooperating partners or both; refresher training for smallholder farmers in CSA; and improvement in the agricultural extension system.

Mechanized Fertilizer Deep Placement: A Transition Towards Climate Smart Agriculture

Mechanized Fertilizer Deep Placement: A Transition Towards Climate Smart Agriculture

Water-Energy-Food Nexus for Climate Change Mitigation in Jordan

In Jordan, the struggle for survival hinges on balancing water, energy, and food security. This arid nation, acutely vulnerable to climate change, holds the Water- Energy- Food (WEF) Nexus approach - weaving water, energy, and food systems into a resilient tapestry. This Abstract delves into Jordan's intricate WEF Nexus, revealing a parched landscape dependent on groundwater, reliant on imported energy, and clinging to agriculture under a harsh sun. However, amidst these challenges lie glimmers of hope: existing initiatives addressing individual sectors and promising interventions leveraging the Nexus approach. The key to a sustainable future is scaling up renewable energy for desalination and efficiency, promoting climate-smart agriculture, and fostering regional resource management. Nevertheless, navigating this complex tapestry demands more than just interventions. Robust governance, empowered stakeholders, and active community engagement are the needles and threads that bind the WEF Nexus together, stitching Jordan's path toward a future where water, energy, and food security sing in harmony. Jordan's narrative is not just about climate vulnerability but about resilience. By embracing the WEF Nexus and its inherent interconnectedness, this nation can transform itself from a thirsty landscape into a beacon of hope, showcasing how climate resilience can develop even in arid regions

Determinants of Smallholder Farmers’ Decisions to Use Multiple Climate-Smart Agricultural Technologies in North Wello Zone, Northern Ethiopia

Climate change presents significant challenges to agriculture in developing nations, affecting farmers’ livelihoods and food security. In Ethiopia, agriculture is crucial to the economy and the well-being of millions. This study focuses on analyzing the determinants that affect smallholder farmers’ adoption of climate-smart agriculture (CSA) technologies in the North Wello administrative zone, northern Ethiopia. Through multivariate and ordered probit econometric models, data from 411 rural household heads were analyzed. Results reveal the synergy among climate-smart agricultural practices in rainfed farming systems, essential for crafting a comprehensive CSA package within an agroecological framework. The multivariate probit estimation results show that education, membership in local organizations, farm size, tropical livestock unit (TLU), irrigated land ownership, plot number, steep slope, farmland distance to home, and access to a local media source are positive determinants for the decision to use the type and several climate-smart agricultural practices. Lack of credit, large family size, distance from extension services, and proximity to the nearest market were all associated with lower adoption of all CSA technologies. The findings suggest that blanket recommendations for climate-smart agricultural technologies for smallholder farmers can be avoided. The complementarities that exist between CSA technologies may require further investigation into how such complementarities have benefits in terms of improving land productivity and food security and reducing climate-related risks for smallholder farmers in Ethiopia and other contexts. Moreover, by emphasizing an agroecological framework, the study promotes environmentally sustainable and socially equitable agricultural practices that are economically viable, contributing to broader environmental sustainability and development goals.

Exploring effects of climate-smart agriculture innovations on women smallholders’ livelihoods in Ethiopia

AbstractStudies do not often provide evidence as to how innovations improve women smallholders’ livelihoods in male-headed households by analyzing women farmers in their own rights which is vital to develop and implement future gender responsive and transformative agricultural innovations. This study investigates if Climate Smart Agriculture (CSA) – specifically conservation agriculture (CA) and small-scale irrigation schemes (SSIS) – improve women smallholders’ livelihoods. A concurrent mixed method was applied, and data was collected using survey, in-depth interviews and focus group discussions (FGDs). Descriptive and t- statistics were used to analyze quantitative data and thematic and narrative analysis methods to analyze qualitative data. Findings demonstrate that gender norms and intersectional identities and experiences of women together with the absence of gender equity and equality based structural works limit improvement in women’s livelihoods. While the use of CA did not change both men and women farmers livelihoods, SSIS improved men users’ financial and physical capitals. Hence, future CSA innovations should first identify the root causes of contextual gender inequalities and CSA innovations should be implemented based on women smallholders needs, experiences and realities. Building women smallholders’ livelihood capitals through off-farm income-generating activities and broadening the operational scale of CSA innovations for addressing strategic gender needs are desired. Explicitly, there is a need to move to a gender transformative approach (GTA) when implementing CSA innovations as GTA challenges and transforms gender norms and intersectional problems including unequal gendered access to livelihood capitals and decision-making power, unequal gender role distributions and gendered representations and implementation processes in economic policies.

Drivers and barriers to climate-smart agricultural practices and technologies adoption: Insights from stakeholders of five European food supply chains

The adoption of climate-smart agriculture (CSA) is a critical component in the transition to a more sustainable food system. However, the transition calls for significant changes in the food production system, in which stakeholders in the supply chain should work collaboratively. So far, most studies have focused on the perceptions of one actor, the farmer, on implementation of CSA practices. This study aims to include also other stakeholders’ perceptions on drivers and barriers to CSA implementation in the primary production for five European food supply chains. Data were collected from stakeholders using a semi-structured interview guide, including farmers, producers and manufacturers, advisory service providers, advocacy institutions, policy officers, researchers, and consultants. The top three drivers to foster the adoption of CSA practices within the five food supply chains touched on economic, institutional and policy, as well as personal and psychological factors. Similarly, the top three barriers limiting adoption of CSA practices were seen to be economic, technology-related aspects, and institutional and policy factors. According to the stakeholders, addressing these barriers requires financial support, policy changes, and capacity-building efforts to make these practices attractive especially to farmers. They also emphasized that improved coordination among stakeholders, incentives for sustainable practices and customized strategies for communicating and disseminating CSA information can help catalyse effective understanding and implementation of CSA practices.

Beneficial effects of plant growth-promoting yeasts (PGPYs) on the early stage of growth of zucchini plants

The use of microbes capable of beneficially interacting with plants is essential for advancing climate-smart agriculture. This approach aims to reduce chemical use while simultaneously enhancing crop productivity. This implies efforts to optimize the criteria for selecting potential plant growth promoters (PGPs), focusing also on yeasts, only recently investigated for their PGP potential. The present study employed a set of Ascomycetes and Basidiomycetes yeasts to test their PGP properties on zucchini (Cucurbita pepo L.), chosen as a fast-growing plant with a vast economical interest. Yeasts were tested alone and as consortium. Seed inoculation with yeasts boosted the early phase of growth of the zucchini plants, primarily affecting the root development. Three strains belonging to the species Schwanniomyces etchellsii, Zygotorulaspora florentina and Holtermanniella festucosa induced a strong and significant enhancement of weight and length of both epi- and hypogeal parts of the plant. Furthermore, the presence of yeasts induced strain-specific modulations in the biochemical profiles of soil, primarily detected in the rhizosphere. This suggests an active interaction between the roots and the inoculated yeast cultures.

Effective extension and access to education drive optimal adoption of climate-smart agriculture interventions in affected tidal floodplains: A case study

Developing countries with predominantly agricultural economies are particularly vulnerable to short-term climate variability and long-term climate change adversities. This provides the context for adopting climate-smart agricultural (CSA) practices to ensure consistent agricultural product supply and food security. Although concepts of CSA tools and strategies are well-established, their adoption trends in developing regions are still undesirable, with little to no empirical understanding of factors contributing to these trends. The current research aims to address this gap of knowledge by assessing the nature of climate change impacts, adaptation strategies, and socio-economic characteristics of the farmers influencing the adoption of CSA techniques in a rural cohort in Southwestern Bangladesh. Systematically designed interview schedules revealed that the most common and devastating consequences of climate change in the study area were increased infestation of pests and diseases. Other overlooked hazards including water-logging, cyclones and cold waves, are posing new threats to regional agriculture by changing conventional patterns. Contrary to the status quo, many CSA technologies, especially indigenous approaches, are widely and effectively adopted by farmers in the studied area to cope with climate change. These adoption tendencies and innovations in CSA were found to be significantly driven by factors such as extension and training programs, education of farmers, and dependence on on-farming income. The findings of the current study provide a preliminary analysis of the attitude, knowledge and trends of CSA technology adoption by farmers in a less-saline floodplain niche of a predominantly salinity-impacted coastal region. The study acts as a model for future relevant investigations and implementations for stakeholders with supply of inputs, technologies and expertise in finding sustainable solutions and appropriate extension for communities around the world confronted with similar challenges.

Adaptation through Climate-Smart Agriculture: Examining the Socioeconomic Factors Influencing the Willingness to Adopt Climate-Smart Agriculture among Smallholder Maize Farmers in the Limpopo Province, South Africa

Agriculture contributes to the South African economy, but this sector is highly vulnerable to climate change risks. Smallholder maize farmers are specifically susceptible to climate change impacts. The maize crop plays a crucial role in the country’s food security as is considered a staple food and feed. The study aimed at examining the socioeconomic factors influencing smallholder maize farmers’ willingness to adopt climate-smart agriculture in the Limpopo Province, South Africa. It was conducted in three different areas due to their specific agro-ecological zones. A multipurpose research design was used to gather data, and multistage random sampling was used to choose the study areas. Subsequently, 209 purposefully selected farmers were interviewed face-to-face using structured questionnaires and focus discussion groups. Descriptive results revealed that 81%, 67%, and 63% farmers in Ga-Makanye, Gabaza, and Giyani were willing to adopt CSA. Using the double-hurdle model, the t-test was significant at 1%, Prob > chi2 = 0. 0000, indicating a good model. At a 5% confidence level, education, crop diversification, and information about climate-smart agriculture (CSA) positively influenced adoption, while household size and agricultural experience negatively influenced it. It is recommended that the Department of Agriculture, Land Reform, and Rural Development provide CSA workshops and educational programs to farmers to enhance their knowledge and decision-making processes regarding adaptation strategies.

An analysis of the perceived effectiveness and upscaling potential of climate-smart agriculture interventions in the Sistan Plain, Iran

The deficient extension of climate-smart agriculture (CSA) interventions in developing regions, where farming livelihood is threatened by natural disasters like drought, is still a concerning dilemma. Development paradigms are not consistent with CSA competencies in providing food security and climatic resilience and often neglect livelihood indices regarding upscaling patterns in CSA development. This research investigated the effectiveness and upscaling potential of CSA interventions in the Sistan Plain in Sistan and Baluchistan province, Iran. A sample of 361 farmers was taken by stratified randomization with proportional allocation. The CSA effectiveness was measured by productivity, income, resilience, and impact mitigation, and the CSA upscaling potential was measured by technical feasibility, technology cost, gender inclusivity, and synergy with government plans. The factors determining CSA effectiveness and upscaling potential were specified by regression models considering farmer households’ livelihood indices. The results revealed that the variables of participation in education, the cultivation area, road connections, hygienic facilities, educational level, house type, farming water resources, cooking facilities, experience in farming, social recognition, and access to shared facilities determined the effectiveness of CSA practices. Also, CSA upscaling potential was found to be influenced by participation in education, the cultivation area, social recognition, farming water resources, house type, hygienic facilities, educational level, experience in farming, road connections, cooking facilities, and number of children.

U.S. food policy to address diet-related chronic disease.

Poor diet is the leading cause of mortality in the U.S. due to the direct relationship with diet-related chronic diseases, disproportionally affects underserved communities, and exacerbates health disparities. Evidence-based policy solutions are greatly needed to foster an equitable and climate-smart food system that improves health, nutrition and reduces chronic disease healthcare costs. To directly address epidemic levels of U.S. diet-related chronic diseases and nutritional health disparities, we conducted a policy analysis, prioritized policy options and implementation strategies, and issued final recommendations for bipartisan consideration in the 2023-24 Farm Bill Reauthorization. Actional recommendations include: sugar-sweetened beverage taxation, Supplemental Nutrition Assistance Program (SNAP) fruit and vegetable subsidy expansion, replacement of ultra-processed foods (UPF) with sustainable, diverse, climate-smart agriculture and food purchasing options, and implementing "food is medicine."

Challenges of implementing a climate-smart agriculture-based curriculum in agricultural vocational schools: evidence from Iran

The research aimed to identify the challenges of developing and implementing a climate-smart agriculture (CSA)-based curriculum in Iran’s agricultural vocational schools. It was exploratory descriptive-analytical in nature and applied in goal, in which data were collected with the library and deep interview method. The research methodology was based on grounded theory. The statistical population was composed of 16 researchers, authors, managers, and experts of the Office of Textbook Compilation of the Organization for Educational Research and Planning and the Research Center of Educational Studies. The participants were selected by the homogenous purposive sampling method. The interview with the target population continued until it reached theoretical saturation. Data were analyzed using the content analysis method. The data collected in the interviews were subjected to open, axial, and selective coding, which resulted in deriving 119 concepts and 28 categories. The results revealed a seven-dimension structure composed of the challenges related to determining educational goals, trainees, trainers’ professional process, teaching methods, curriculum content selection and organization, curriculum implementation, and curriculum appraisal. The results can help the experts in the Office of Textbook Compilation experts adopt smarter policies and solutions to solve the challenges of developing and implementing a CSA-based curriculum in agricultural vocational schools in Iran.

Farmers’ Participation in Climate Smart Agriculture Initiatives and Adoption Decisions in the Arsi and East Shewa Zones of Oromia Region, Ethiopia

Climate change is a major challenge to sustainable agricultural production in the world. The intricacy of the problem requires farmers’ compliance with regenerative agricultural practices that can facilitate the conservation of fragile productive systems while sustaining their productivity. Accordingly, various climate change management strategies have been promoted in Ethiopia. This paper analyzed farmers’ participation in CSA practices and the determinants of adoption in the Oromia region of Ethiopia. The data were collected during the 2020 cropping season from 420 randomly selected farmers in the Arsi (highland) and East Shewa (lowland) zones of the Oromia region. The data was analyzed with descriptive and Logit regression. The results showed that of the total thirteen climate-smart agricultural practices that were assessed, about 6 and 4 were adopted by more than 50% of the farmers in the highland and lowland, respectively. Also, 21.0% and 42.4% of respondents from highland and lowland respectively participated in CSA programs or projects. Moreover, 35.5% and 34.8% of the highland and lowland agroecology farmers respectively adopted some CSA after project participation. In highland agroecology, crop rotation, crop residual management, crop diversification, and intercropping were the mostly used practices, while crop rotation, adjustment of planting time, minimum tillage, and planning of drought-resistant varieties were mostly used by lowland agroecology farmers. Moreover, logistic regression results reveal that CSA adoption is influenced by age, education, gender, family size, credit support, experience, extension support, non-agricultural income, and livestock holding. It was concluded that adoption of CSA was low, and promotion of extension support and CSA participation experiences will facilitate adoption of some CSA practices. More importantly, extension support should focus on CSA practices that were widely used by the farmers. Res. Agric. Livest. Fish. Vol. 11, No. 1, April 2024: 79-91

Towards Sustainable Agriculture: Integrating Agronomic Practices, Environmental Physiology and Plant Nutrition

Sustainable agriculture aims to meet the growing global demand for food without compromising environmental integrity. This review paper explores the integration of agronomic practices, environmental physiology, and plant nutrition as pathways toward sustainable crop production. Intensive agricultural practices have led to significant problems such as soil degradation, loss of biodiversity, and environmental pollution. Recent advancements in plant physiology have enhanced our understanding of plant growth and response to biotic and abiotic stresses. Optimizing crop production in a sustainable manner depends on insights into key processes like photosynthesis, water use efficiency, and nutrient uptake. This review discusses the role of plant growth-promoting microorganisms (PGPMs) as biofertilizers, providing an alternative to harmful agrochemicals. PGPMs can improve soil health and promote plant growth when applied to soil, seeds, or plant surfaces, reducing reliance on synthetic fertilizers and pesticides. Additionally, nanotechnology in agriculture is examined, illustrating how nanomaterials (NMs) and nano-based fertilizers can enhance nutrient absorption and increase crop yields. Beyond these scientific approaches, there is an urgent need to implement novel agricultural practices that support sustainability. The world population is growing at a disquieting rate, placing tremendous pressure on natural resources. This threatens future generations' access to nutritious food and clean air. Innovative approaches like climate-smart agriculture, organic farming, biodynamic agriculture, sustainable intensification, and regenerative agriculture, along with practices such as integrated farming systems, precision agriculture, integrated nutrient management, and integrated pest management, have proven to safeguard agricultural sustainability. By integrating these innovative approaches and practices, it is possible to meet the increasing demands for food while preserving the environment.

Multi-amplicon nitrogen cycling gene standard: An innovative approach for quantifying N-transforming soil microbes in terrestrial ecosystems

Agriculture accounts for nearly three-fourths of all nitrous oxide (N2O) anthropogenic emissions, a potent greenhouse gas (GHG). Improvements in agricultural management practices are critical for improving plant nitrogen (N) use efficiency and reducing N2O emissions. While implementing “climate-smart” management can reduce N2O emissions, building a linkage between these emissions and the N-cycling microbes that drive them will require N-cycling gene assays that are cost-effective, practical, and accessible to climate-smart researchers. In a recent study, a group of researchers demonstrated the suitability of synthetic oligonucleotides to serve as real-time quantitative PCR (qPCR) standards for quantifying microbial genes in soils. While this study is not based on that study, our results complement their findings and offer fresh insights into this novel methodology. Here, we describe an innovative approach that provides precision in the absolute quantification of five N-transforming target genes (AOB amoA, AOA amoA, nirK, nirS, and nosZ) in soils. Similar to the aforementioned study, our method obviates the cost-intensive aspects of traditional qPCR methods for preparing standard curves in soil microbial ecology (e.g., gel purification of PCR products and in-vivo cloning of plasmids) and is capable of being extended to any biochemical system, or environment of interest. Additionally, our qPCR approach provides several advantages: it utilizes a single multi-amplicon synthetic oligonucleotide, requires only a single dilution series and one stock solution to quantify all gene targets, and contains a non-edaphic gene (ZIKV) that can serve as a soil spike to determine DNA extraction efficiency and DNA recovery estimates. Furthermore, our protocol mitigates PCR inhibition from soil-derived substances using a modified DNA extraction protocol and inhibitor-tolerant polymerase. Ultimately, our work aims to reduce the technical burden on non-biologists/biochemists when conducting soil microbiological assays, support the development of climate mediation practices, and advance climate-smart agriculture goals.

Factors influencing small holder farmers adoption of climate SMART agriculture practices in Welmera Woreda, Central Ethiopia

Adoption of climate-smart agriculture practices are believed to have significantly lessened the devastating impact of climate change on agriculture. However, in countries like Ethiopia, the adoption and use level of climate-smart agriculture practices remains low. The understanding of farmers’ levels of CSA practice adoption and influencing factors is therefore crucial. The goal of the study is to evaluate the degree to which various CSA practices were being used in the study area, as well as adoption determinants. The study was conducted in Welmera district, Oromia, Ethiopia. Three kebeles were chosen from the district, and a random sample of 306 farmers was picked. We used a cross-sectional household survey, a focus group discussion, and interviews with key informants. A multivariate probit model was employed to investigate the factors influencing the adoption of multiple climate-smart agriculture practices. According to the result, conservation agriculture, integrated soil fertility management, and crop diversification are the most often used CSA practices. The results also revealed that male farmers outperformed female farmers in terms of crop diversity and improved animal feed and feeding practice adoption. The age of farmers has a considerable and unfavorable impact on their likelihood of adopting improved soil fertility management and crop diversification practices. However, it has a positive and considerable impact on the adoption of agroforestry practices. With regards to economic factors, having a relatively big farmland area considerably enhances the adoption of conservation agriculture, enhances soil fertility management and crop diversity, and improves livestock feed and feeding methods and post-harvest technology practice. Improved livestock feed and feeding are more likely to be used with higher farm income. Having a significant number of animals strongly promotes the adoption of conservation agriculture, and access to financial services positively impacts agroforestry, diversification of crops, and postharvest technology practice adoption. Furthermore, institutional factors including access to agricultural extension services and training were discovered to be important and beneficial for crop diversification; similarly, access to field day participation was discovered to have a significant and positive impact on the adoption of conservation agriculture and improved soil fertility management practices. It is critical to raise awareness about climate change among farmers and experts, as well as to incorporate location-specific CSA practices into agricultural programs.

Normalised difference moisture index in water stress assessment of maize crops

Remote sensing is a promising technique for better management of water resources in agriculture through improvement of dynamic control and operational scheduling on irrigated croplands. The main goal of this study was to identify the possibilities of application of the normalised difference moisture index (NDMI) to water stress monitoring in maize crops, and to determine the relationship between the index and soil moisture content. The study was carried out in 2019–2021 in the experimental fields of disturbed maize, cultivated on dark-chestnut soils in the Southern Ukraine at the NAAS Institute of Climate-Smart Agriculture. The crop cultivation technology was common for the conditions of the steppe zone of Ukraine. Actual soil moisture content was determined by gravimetric method in the pre-sowing and post-harvest period. The NDMI values were calculated using cloudless aerospace images from the satellites Landsat 8, Sentinel-2, and MODIS with 250 m resolution. It was revealed that the seasonal NDMI dynamics perfectly reflected the water-supply conditions of the disturbed maize, and could be used for operational monitoring and scheduling of irrigation. The parameters of the water-supply conditions were determined in 2021, which was the wettest year of the study: the cumulative seasonal NDMI reached 1.71, while the highest water stress was recorded in the driest year, 2020, – the cumulative NDMI was 0.15. Additionally, there was a moderately strong negative correlation between NDMI and soil moisture content, and the coefficient of determination was 0.62. The linear regression models, developed to predict soil moisture content in the 0–100 cm layer depending on the NDMI values, had good fitting quality and reasonable accuracy, but they required further calibration and extension of the initial dataset to provide more robust and reliable results for practical implementation. Based on the results of the study, spatial NDMI could be considered a good and reliable tool for improving irrigation water management. Further studies should focus on the practical implementation of the NDMI-based model of moisture-content estimation, as well as on the possibilities of the index usage for mapping irrigated lands.

Gender gaps in the adoption of climate‐smart agricultural practices: Evidence from sub‐Saharan Africa

AbstractIn this paper we examine whether there are significant gender differences in the adoption of climate‐smart agricultural (CSA) practices in sub‐Saharan Africa. Using individual‐level data from four sites in Kenya, Uganda and Senegal, our empirical analysis provides robust evidence that men have a higher likelihood of adopting high‐return CSA practices including modern chemical fertiliser, improved high‐yielding varieties and drought/pest tolerant livestock practices. In contrast, women tend to have a higher likelihood of adopting low‐risk and low‐return traditional CSA practices such as water harvesting, crop covering, rangeland management and pest management. Our subsample analysis shows significant heterogeneity in the gender gap across countries. The results of the decomposition of the observed gender gap show that personal values and norms, access to weather and production information and farm characteristics are important factors that explain the gender differential in the likelihood of CSA adoption. Our findings imply that equalising access to key resources such as plots of land, information and decision making power will be crucial to close the gender gap in the adoption of CSA practices. This is particularly important given the differential impacts of climate change between men and women in sub‐Saharan Africa.

Greenhouse gas mitigation and soil carbon stabilization potential of forest biochar varied with biochar type and characteristics

Biochar is increasingly used in climate-smart agriculture, yet its impact on greenhouse gas (GHG) emissions and soil carbon (C) sequestration remains poorly understood. This study examined biochar-mediated changes in soil properties and their contribution to C stabilization and GHG mitigation by evaluating four types of biochar. Soil carbon dioxide (CO2) and nitrous oxide (N2O) emissions, soil chemical and biological properties, and soil organic carbon (SOC) mineralization kinetics were monitored using greenhouse, laboratory, and modeling experiments. Three pine wood biochars pyrolyzed at 460 °C (PB-460), 500 °C (PB-500), 700 °C (PB-700), and one pine bark biochar from gasification at 760 °C (GB-760) were added into soil at 1 % w/w basis. Soils amended with biochar were used to cultivate sorghum for three months in a greenhouse, followed by three months of laboratory incubation. Data obtained from laboratory incubation was modeled using various statistical approaches. The PB-500 and PB-700 reduced cumulative N2O-N emissions by 68.5 % and 73.9 % and CO2 equivalent C emissions by 66.9 % and 72.4 %, respectively, compared to unamended control. The N2O emissions were positively associated with soil nitrate N, available P, and biochar ash content while negatively associated with SOC. The CO2 emission was negatively related to biochar C:N ratio and volatile matter content. Biochar amended soils had 49.2 % (PB-500) to 87.7 % (PB-700) greater SOC and 22.9 % (PB-700) to 48.1 % (GB-760) greater sorghum yield than the control. While PB-700 had more saprophytes than the control, the GB-760 yielded a greater yield than biochars prepared by pyrolysis. Microbial biomass C was 7.23 to 23.3 % greater in biochar amended soils than in control. The double exponential decay model best explained the dynamics of C mineralization, which was associated with initial soil nitrate N and available P positively and total fungi and protozoa biomass negatively. Biochar amendment could be a climate smart agricultural strategy. Pyrolysis pine wood biochar showed the greatest potential to reduce GHG emissions and enhance SOC storage and stability, and gasification biochar contributed more to SOC storage and increased crop yield.

Rainfall reliability and maize production in the Bamenda Highlands of Cameroon

The long-term average rainfall for a given period (month, season or year) scarcely indicates reliability because rainfall in low latitudes varies significantly from one year to the other. The less variable rainfall is, the more reliable it is, as the index of variability measures the likelihood of repetition in the mean amount of rainfall. This study bridges some gaps in related studies in the Bamenda Highlands, such as a study assessing climate change impacts on food security, where the Rainfall Anomaly Index was used and another study on the impact of rainfall on maize production using the Standardized Precipitation Index. The objectives of this study are to assess rainfall reliability and establish the impact of rainfall reliability on maize production. Rainfall data were collected from 15 stations, while maize output was collected for four localities. Results revealed that rainfall is still reliable for 13 stations, with a coefficient of variations of 9.62 to 18.54 %, while Ndop and Ndawara recorded unreliable rainfall of 23.14 % and 30.97 % respectively. Rainfall reliability was complemented by the Standardized Precipitation Index, which showed that only 53.45 % of rainfall episodes were normal to sustain maize production, while 46.55 % were events of rainfall deficits. Maize production has been decreasing in Ndu, Oku and Nkum while increasing in Ndop. These findings reflect the realities of other tropical mountainous regions in the world. Faced with future climatic uncertainties, farmers should embrace agroecological practices, climate-smart agriculture, conservation agriculture, Nature-based Solutions, Ecosystem-based Adaptation and diversification of production systems and livelihood sources to ensure food security.