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    Agronomic, Socio-Economic, and Environmental Challenges and Opportunities in Nepal’s Cereal-based Farming Systems
    (2021) Timothy J. Krupnik; Jagadish Timsina; Krishna P. Devkota; Bhaba P. Tripathi; Tika B. Karki; Anton Urfels; Yam Kanta Gaihre; Dyutiman Choudhary; Abdu Rahman Beshir; Vishnu Prasad Pandey; Brendan Brown; Hom Gartaula; Sumona Shahrin; Yuga N. Ghimire
    With economies heavily dependent on agriculture, South Asia is the world’s most poverty-dense region. Nepal—a country of considerable geographic variability ranging from population-dense low-elevation Terai region to the sparsely inhabited, poorly accessible Himalayan hills and mountains—has enormous environmental and socio-economic challenges to agricultural development. Runoff from the hills and mountains feed networks of rivers that are crucial for supply of surface and groundwater for the Terai and northern India and Bangladesh, benefitting approximately one-fifth of the world’s population. Nepal’s farming systems are complex, with insufficient documentation of research evidence on the challenges and opportunities facing them. This review documents the key environmental, socio-economic and agronomic issues affecting cereal-based farming systems in Nepal. Evidences suggest farmers in the hills and mountains primarily practice integrated crop-livestock-tree based agroforestry systems with local varieties of crop and livestock species, and use farm-derived organic amendments and limited external inputs, resulting in low but stable yields. The Terai’s cropping systems are predominantly rice-based, with wheat, maize and pulses grown in rotation with low to moderate use of inputs, although high yielding varieties are increasingly 156 Timothy J. Krupnik et al. common. Major environmental challenges in the high and mid-hills include erosion and soil degradation, while in the Terai, reduced soil fertility and sub-optimal management of water resources are important constraints. Climate variability and extremes are cross-regional challenges. Socioeconomic issues include land use policy, labor out-migration and agricultural feminization. Large gaps between potential and farmers’ yields are consistent concerns. While summarizing past and current agronomic research findings, this review suggests new research needs and agricultural development pathways that could address these environmental, socioeconomic and agronomic issues and challenges
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    An Assessment of Inherent Chemical Properties of Soils for Balanced Fertilizer Recommendations for Cocoa in Ghana
    (2018-04-04) Ekwe L. Dossa; A. Arthur; Wilson Dogbe; Abdoulaye Mando; A. A. Afrifa; S. Acquaye
    Sustainable cocoa production in Ghana would require a shift in fertilizer recommendations from general applications to site-specific recommendations of fertilizers that account for initial fertility status and actual nutrient needs of soils on which cocoa is grown. A soil fertility survey was conducted in the major cocoa regions of Ghana covering the major benchmark soils. Two hundred and twenty four plots were sampled and composite surface soils collected and analyzed for selected fertility characteristics. The results show that most of the cocoa soils have low inherent fertility characterized by low C, N and exchange capacity. All the cocoa soils sorb P, which may limit availability of P in the soil solution. The soils generally are acidic, and soils in Western region, especially the Ferralsols, show the most acidic reaction with substantially measurable exchangeable Al. The results suggest that these differential characteristics of the surveyed soils should be considered in formulating balanced site-specific fertilizer for cocoa in Ghana.
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    Assessment of Soil Fertility Status and Integrated Soil Fertility Management in Ghana
    (2018-04-04) Andre Bationo; A. Kwaw; Joseph Opoku Fening
    The total land area of Ghana is 23,853,900 ha of which 57.1% (13,628,179 ha) is suitable for agriculture but most of the soils are of low inherent fertility. The coarse nature of the soils has an impact on their physical properties and water stress is common during the growing season. Extensive areas of country’s land area particularly the Interior savannah zone have suffered from severe soil erosion and land degradation in various forms. The soil nutrient depletion rates in Ghana is projected as 35 kg N, 4 kg P and 20 kg K ha−1. The extent of nutrient depletion is widespread in all the agro-ecological zones with nitrogen and phosphorus being the most deficient nutrients. Nutrients removed from the soils by crop harvest have not been replaced through the use of corresponding amounts of plant nutrients in the form of organic and inorganic fertilizers. There is therefore a steady decline in crop yield levels and increased food production is presently due mostly to extension in the area under cultivation. Overall percentage increase in cultivated area between 2000 and 2008 is about 17.3% (SRID 2008). The average yields of most of the crops are 20–60% below their achievable yields, indicating that there is significant potential for improvement While Ghana has one of the highest soil nutrient depletion rates in SSA, it has one of the lowest rates of annual inorganic fertilizer application – only 8 kg per hectare. An increase in food security requires increased productivity strategies that will raise yields for most crops toward their achievable levels, mostly by the adoption of intensive and improved technologies, including the use of fertilizers, improved seeds and best management practices. While African policy makers and International donors recognize the urgency of raising fertilizer use by small holder farmers, for achieving both agricultural growth and poverty alleviation objectives, there is little consensus on the most appropriate policy and programmatic course of action. Most efforts to raise fertilizer use in SSA over the past decade have focused on fertilizer subsidies and targeted credit programmes with hopes that these programmes could later be withdrawn once the profitability of fertilizer use has been made clear to newly adopted farmers and once they have become sufficiently capitalized to be able to afford fertilizer with their own working capital. Relatively little emphasis has been given to improving the profitability of fertilizer use through understanding the most productive levels and combinations of nutrient input for various agro ecological areas, management practices and market options. Inorganic fertilizer does not improve agricultural productivity in isolation. Information on the fertility status and agricultural potential of the soils are also required. Complementary inputs such investment in soil and water conservation for efficient end optimal nutrient uptake is also important. Improved soil fertility management through increased levels of fertilizer use, increased use of available organic soil amendments, and improved farm management practices, together with the use of improved seed, can result in positive gains in farm productivity. This increase in productivity is demonstrated by the SAWA technology in rice production where yield on farmers’ fields increased from 1 ton/ha to 5 tons/ha (Buri et al. 2007). There is lack of information on the profitability of the different soil-crop-fertilizer combinations that could be employed in the different parts of the country. The lack of such information on crop-fertilizer profitability across the country means that farmers cannot tell how much they stand to gain or lose by applying a particular type of fertilizer on a particular crop. This increases their risk and creates a disincentive for use of fertilizer. Information about profitability levels can serve as an incentive for inorganic fertilizer use. Most simply, expected Value Cost Ratios (VCR) from fertilizer use can guide farmers’ decisions. Knowledge of soil characteristics and processes regulating nutrient availability and supply to crops is essential to raise productivity per unit of fertilizer nutrient applied. The recommendation of the African Fertilizer Summit (2006) to increase fertilizer use from 8 to 50 Kg/ha nutrients by 2015 reinforces the importance of fertilizer for increasing crop productivity and attaining food security and rural wellbeing in Ghana. The impact of this target will however vary depending upon the agronomic efficiency of applied fertilizer. This efficiency varies across ecological zones, farms and fields within farms and greatly affects the returns to the recommended 50 Kg/ha. The application of insufficient fertilizers and inappropriate nutrient conservation practices by farmers contribute to accelerating the rapid decline in soil fertility. The efficient uses of both inorganic and organic fertilizers, through Integrated Nutrient Management approach, will form an important element of a holistic approach for sustainably increasing crop production in Ghana
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    Building Bridges between Natural Nutrient Sources and Fertilizers for Soil Health and Sustainable Food Security
    (2022) Balu L. Bumb; J.C. Katyal; Upendra Singh
    A common piece of land served the purpose of arable farming and animal rearing; crop residues and animal dung and excreta enriched soil fertility. The adoption of green revolution (GR) technologies embodied in improved seeds and fertilizers accelerated growth in global food grain production from 0.9 billion tons (giga (G) tons) in 1961 to 3.1 G tons in 2017. Plants grow by capturing, absorbing, and drawing essential mineral nutrients from diverse sources and resources. Organic manures constitute plant (crop residues) and animal wastes (animal dung) including the by-products obtained after processing their economic parts. Crop residues are largely applied by incorporating or left on the surface to rot. Fertilizers are synthetic chemicals or available from mineral sources. The centrally planned economies (CPEs) of Eastern Europe and Eurasia (then the former Soviet Union) also promoted growth in fertilizer use for food security reasons.
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    Challenges to Agroecosystem Management
    (2013-08) Petina L. Pert; Eline Boelee; Devra I. Jarvis; David Coates; Bindraban, Prem S.; Jennie Barron; Rebecca E. Tharme; Mario Herrero
    As growth in population, gross domestic product (GDP) and consumption continues, further demands are placed on land, water and other resources. The resulting degradation can threaten the food security of poor people in fragile environments, particularly those whose livelihoods rely largely on agricultural activities. The concept of diversifi ed or multifunctional agroecosystems is a relatively recent response to the decline in the quality of the natural resource base. Today, the question of agricultural production has evolved from a purely technical issue to a more complex one characterized by social, cultural, political and economic dimensions. Multifunctional agroecosystems carry out a variety of ecosystem services, such as the regulation of soil and water quality, carbon sequestration, support for biodiversity and sociocultural services, as well as meeting consumers’ needs for food. In turn, these systems also rely on ecosystem services provided by adjacent natural ecosystems, including pollination, biological pest control, maintenance of soil structure and fertility, nutrient cycling and hydrological services. However, poor management practices in agroecosystems can also be the source of numerous disservices, including loss of wildlife habitat, nutrient runoff, sedimentation of waterways, greenhouse gas emissions, and pesticide poisoning of humans and non-target species. This chapter discusses the challenges to agroecosystem management, and how adopting a diversifi ed approach will enable farmers to farm longer and more sustainably in an environment of greater uncertainty, in the face of climate change.
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    Characterization of Phosphate Rocks
    (2004) Van Kauwenbergh, S.J.; McClellan, G.H.
    Characterization studies of phosphate rock (PR) samples should provide data on: (i) the composition of the apatite, other phosphate minerals and gangue minerals; (ii) the relative amounts of mineral species present (estimated); and (iii) the particle size of the various minerals in the rock fabric, etc. It is possible to combine this information with a comprehensive chemical analysis to determine the distribution of chemical species among the mineral components. Based on such an evaluation, it is possible to estimate the potential for beneficiation, suggest possible beneficiation routes, and make a preliminary assessment of the suitability of PRs for various fertilizer production processes and/or their applicability for direct application.
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    Conservation Agriculture for Sustainable Intensification: Global Options and Opportunities
    (2022) Amir Kassam; Yashpal Singh Saharawat; I.P. Abrol
    Innovations such as Conservation Agriculture (CA) systems and the resulting ecological understanding of sustainable production are leading a paradigm change in the food and agriculture system globally. The resulting impact is the opening up of new and more profitable ways of managing agricultural lands and improving livelihoods, of investing in agricultural land for commercial purposes, and enhancing and being rewarded for ecosystem services. Agriculture is no longer the sector to employ the poor and the uneducated. It is a place where greater technical and managerial skills are going to be demanded in order to save the human race and the planet. Agriculture has become a calling for everyone, especially the youth, to reengage and double their efforts to achieve and sustain food security, address agricultural land degradation, achieve more from less, and respond to climate change. We must concentrate on promoting all aspects of CA for the benefit of the farmer, wherever he or she may be farming, however poor or rich, small or large, as well for the society and the planet. All disciplines and people have a role to play because the option and opportunity, which we all must seize, is at the level of a paradigm change – like moving from a flat Earth mindset to a round reaching mindset. All aspects of the food and agriculture systems must be realigned to the new paradigm over the coming decades across the world.
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    Conservation Agriculture in South Asia
    (2022-02) Yashpal Singh Saharawat ; Gill, M; Mahesh K. Gathala; Tika B. Karki; Wijeratne, D.B.T.; Samiullah, S.; Neelam Chaudhary; Md. Enamul Haque; Richard W. Bell; C.M. Parihar; Hari Sankar Nayak; Rajbir Singh; R. K. Malik; Upendra Singh; Raj Paroda; Amir Kassam
    South Asia, a home of 1.7 billion people houses the most poor and malnourished people globally. The region need to double its food production by 2050. Current scenario puts South Asian agriculture in a dilema facing triple challenges: to increase production to meet the food demand of growing human population with a lower environmental footprint, preserve natural resources and mitigate or adapt to the changing climatic scenarios. Conservation Agriculture offers a number of benefits such as arresting and reversing the resource degradation, decreasing cultivation costs, making agriculture more resource – use efficient, competitive and sustainable whilst increasing resilience to climatic variability and improving livelihood incomes in South Asia. The CA approach for managing agro ecosystems is of paramount significance in improving soil health, sustained productivity and maintaining natural biodiversity. However, there is still a large knowledge gap in understanding of nutrient and water management in CA Systems
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    Crop and Cropping Systems Management Practices and Benefits in Conservation Agriculture Systems
    (2020) Muhammad Farooq; Ahmad Nawaz; Yashpal Singh Saharawat; Timothy Revees; Kadambot H M Siddique
    Conservation Agriculture (CA) offers a pragmatic option for improving soil health, crop productivity and resilience, generating biomass, increasing factor productivity and total output, and reducing greenhouse gas emissions. Most crops, including cereal, legume, oilseed, fibre and vegetable crops, can be successfully grown under CA systems, as can a range of forages. CA can produce yields that are comparable to, or higher than, conventional systems on a range of soil types and under variable climatic conditions. The use of diverse cropping/farming systems in CA can increase resilience to both biotic and abiotic stresses; enhance yield and economic stability, and reduce and/or slow declines in long-term soil productivity. In this chapter, the authors summarize the performance of various crops in CA systems across the globe and elaborate on the management practices and benefits of including those crops in CA systems. They also highlight various cropping systems that might be suitable for long-term sustainability of CA systems. Case studies are also included.
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    Decision Support Tools for Improved Resource Management and Agricultural Sustainability
    (2016-04-19) Upendra Singh; Paul W. Wilkens ; Walter E Baethgen; TS Bontkes
    The need for increasing agricultural productivity on a sustainable basis is the primary concern of the agricultural research and development community. The International Fertilizer Development Center’s (IFDC) interest in natural resource and environmental management, specifically, efficient and improved use of inorganic, organic, and biological sources of nutrients, led to the realization that many of the problems in the nutrient efficiency domain can be adequately handled only by a multidisciplinary research approach. To achieve multidisciplinarity, a switch from reductionist scientific approach to systems approach was necessary.
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    Dissipation and Recycling: What Losses, What Dissipation Impacts, and What Recycling Options?
    (2014-01-01) Masaru Yarime; Cynthia Carliell-Marque; Deborah T. Hellums; Yuliya Kalmykova; Daniel J. Lang; Quang Bao Le; Dianne Malley; Leo S. Morf; Kazuyo Matsubae; Makiko Matsuo; Hisao Ohtake; Alan P. Omlin; Sebastian Petzet; Roland W. Scholz; Hideaki Shiroyama; Andrea E. Ulrich; Paul Watts
    This chapter describes the activities in the Dissipation and Recycling Node of Global TraPs, a multistakeholder project on the sustainable management of the global phosphorus (P) cycle. Along the P supply and demand chain, substantial amounts are lost, notably in mining, processing, agriculture via soil erosion, food waste, manure, and sewage sludge. They are not only critical with respect to wasting an essential resource, but also contribute to severe environmental impacts such as eutrophication of freshwater ecosystems or the development of dead zones in oceans. The Recycling and Dissipation Node covers the phosphorus system from those points where phosphate-containing waste or losses have occurred or been produced by human excreta, livestock, and industries. This chapter describes losses and recycling efforts, identifies knowledge implementation and dissemination gaps as well as critical questions, and outlines potential transdisciplinary case studies. Two pathways toward sustainable P management are in focus: To a major goal of sustainable P management therefore must be to (1) quantify P stocks and flows in order to (2) identify key areas for minimizing losses and realizing recycling opportunities. Several technologies already exist to recycle P from different sources, including manure, food waste, sewage, and steelmaking slag; however, due to various factors such as lacking economic incentives, insufficient regulations, technical obstacles, and missing anticipation of unintended impacts, only a minor part of potential secondary P resources has been utilized. Minimizing losses and increasing recycling rates as well as reducing unintended environmental impacts triggered by P dissipation require a better understanding of the social,technological, and economic rationale as well as the intrinsic interrelations between nutrient cycling and ecosystem stability. A useful approach will be to develop new social business models integrating innovative technologies, corporate strategies, and public policies. That requires intensive collaboration between different scientific disciplines and, most importantly, among a variety of key stakeholders, including industry, farmers, and government agencies.
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    Economic Efficiency of Sorghum Microfertilizing in Smallholder Farms in the North-Sudanian Zone of Burkina Faso
    (2018-04-04) Arahama Traoré; Badiori Ouattara; H. Sigué; François Lompo; Andre Bationo
    The mineral fertilizer microdosing (MD) technique was disseminated in the North-Sudanian zone of Burkina Faso for 3 years, using various extension tools. This study aimed to analyze the economic efficiency as well as farmers’ perception of the use of MD technique. Quantitative and qualitative data were collected from 60 demonstration plots conducted by innovative farmers and from 300 households, using an interview guide during the focus groups. The results of the demonstration trials showed that this innovation significantly increased (P˂0.05) sorghum productivity compared to farmer’s practice. It even tripled sorghum yields when combined with soil and water conservation (SWC) techniques, and the use of improved seed varieties. It also led to the efficient use of production capital with cost-benefit ratios ranging from 1.3 to 6.9 depending on the sorghum germplasm and its combined use with SWC techniques. Farmers acknowledged the positive effects of MD technique on their socio-economic well-being through higher incomes from sorghum production and improved food availability. These results challenged policy makers to trigger actions aiming at promoting large-scale adoption of MD technique for sustainable local development.
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    Economic Factors in the Adoption and Utilization of Phosphate Rocks
    (2004) Kuyvenhoven, A.; Sen H. Chien; E. Casanova
    The degradation of soil fertility due to increased population pressure, reduced fallow periods, deforestation, and improper agricultural practices poses a significant challenge to sustainable agriculture in many developing regions. Phosphorus (P) deficiency, in particular, has emerged as a critical issue, threatening agricultural viability and food security. This paper examines the economic factors influencing the adoption and utilization of phosphate rocks (PR) as a means to address soil fertility depletion. Constraints such as limited financial resources, poor distribution systems, lack of knowledge about PR utilization, and dependence on fertilizer aid hinder widespread adoption. Additionally, factors such as ownership rights, farm size, access to credit, and labor availability influence farmers' decisions regarding PR adoption. While PR application offers potential benefits in terms of soil fertility improvement and long-term agricultural productivity, challenges related to production costs, transport, and distribution must be addressed. Policy interventions such as pricing policies, organizational support, agricultural market development, and risk protection measures are crucial to incentivize PR adoption and promote sustainable agriculture.
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    Effect of Hill Placement of Nutrients on Millet Productivity and Characteristics of Sahelian Soils of Niger: Analysis of Yield Trend After Three Years of Cropping
    (2018-04-04) Dougbedji Fatondji; Ramadjita Tabo; Tom C. Hash; Andre Bationo
    Reports from implementation of the low-input mineral fertilizer microdosing technology have shown up to 120% yield increase. However on the acidic Sahelian soils (pH 4–5 (H2O)) with low carbon content (0.2%), the question is whether applying such small dose would not lead to nutrient mining over years, which ICRISAT set three studies of 3 years each to address. Experiments 1 (2003) and 2 (2008) involved three planting densities, two pearl millet varieties and four fertility management options with removal of crop residue in experiment 1. Experiment 3 (2010) involved the combinations of 4 rates of organic and mineral fertilizers and 10 millet varieties. Both organic and mineral inputs were hill-applied. In all experiments nutrient hill placement resulted in total biomass increase in the second and third years compared to the control. After 3 years of cropping, yield decrease of −2307 kg.ha−1 was observed with the control in experiment 1 between years 1 and 3, while −1238 kg.ha−1 was observed with 6 g NPK per hill which was statistically significant. In experiment 3 yield decrease was −1516 kg.ha−1 with the control and −648 kg.ha−1 with 300 g per hill of organic manure. Soil pH decreased by 0.17 in NPK amended plots whereas it decreased by 0.29 in the others as observed in experiment 1. In all case, biomass decreased but in lower amplitude with organic manure addition.
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    Electrochemistry of the Double Layer: Principles and Applications to Soils
    (2018-02-06) Upendra Singh; Goro Uehara
    There has been a minimal revision in this chapter compared to the first edition. A section on simulating nutrient dynamics has been included to illustrate a recent application of the electrical double-layer theory in modeling and in transport of interacting solutes. The objective of the chapter remains — providing students a simple and complete mathematical explanation of double-layer theory. A thorough discussion of the strengths and weaknesses of double-layer theory has been sacrificed for completeness of theory and its derivation. Many steps that are omitted in advanced papers on the subject are included for clarity and continuity in this chapter. The aim of this chapter is to entice a larger number of scientists to adopt and apply the double-layer theory. Double-layer theory remains underutilized in aquatic chemistry and particularly in soil science because potential users have not learned the basic relationships that comprise it.
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    Enhancing Soil Security for Smallholder Agriculture
    (2014-11) Johan Bouma; Bindraban, Prem S.; Niels H. Batjes; M.P.W Sonneveld
    Smallholder agriculture plays a vital role in feeding and sustaining over one billion people in the developing world, particularly in ecologically and climatically vulnerable landscapes. These farmers face significant challenges, including declining productivity, insecure land tenure, insufficient infrastructure, and limited access to education, technology, and financial services. In developed countries, smallholder farmers often focus on niche markets and ecosystem services in the face of competition from large commercial farms. This chapter explores the diverse small farming systems in both developing and developed countries and their capacity to address three key challenges: meeting the increasing global demand for food, adapting to water scarcity and climate change, and ensuring sustainability. The role of soils in smallholder agriculture and their contribution to ecosystem services are emphasized, with a focus on soil security. Case studies from different regions illustrate the importance of local conditions and sustainable soil management practices. The chapter also discusses the need for a transition period and the potential of intermediate-sized farming enterprises to provide ecosystem services and enhance soil security. The evolving role of soils within the broader socioeconomic and ethical context of smallholder agriculture is highlighted, recognizing that soils are a fundamental resource for farmers worldwide. The chapter concludes by advocating for precision agriculture and transdisciplinary research to address the multifaceted challenges facing smallholder agriculture, ultimately contributing to global food security and sustainable development.
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    Estimating DSSAT Cropping System Cultivator-Specific Parameters Using Bayesian Techniques
    (2011-01) James W. Jones; Jianqiang He; Kenneth J. Boote; Paul W. Wilkens ; Cheryl H. Porter; Z. Hu
    Crop models are highly useful for simulating crop and soil processes in response to variations in climate and management. However, if one wishes to simulate a crop's performance in a specific soil and climate for a particular set of management inputs, cultivar-specific parameters (CSPs) are needed because of the genetic variations among cultivars of any crop. In this chapter, we summarized methods that have been used to estimate CSPs for the CERES and CROPGRO-based models in the Decision Support System for Agrotechnology Transfer (DSSAT) cropping system model. We primarily described a Bayesian parameter estimation procedure (the Generalized Likelihood Uncertainty Estimation, or GLUE) for use in estimating CSPs in DSSAT. The procedure is simple to use, requiring only that users select a crop, a cultivar, and the data for use in the estimation procedure from a list of data available for that cultivar in the DSSAT system. Results are displayed for users to view and copy to the standard cultivar file in DSSAT for the crop involved. The procedure does require a large number of model runs; we recommend 6000 but users can optionally change this number. Two cultivars, ‘Prisma’ maize (Zea mays L.) and ‘Williams’ soybean [Glycine max (L.) Merr.] were selected to demonstrate the performance of DSSAT GLUE program. For Prisma maize, two experiments conducted in Zaragosa, Spain in 1995 and 1996 were selected; for Williams soybean, three experiments individually conducted in Wooster, OH and Gainesville, FL, were selected for the demonstration. Results showed that the GLUE method performed better than the arbitrary default CSPs and slightly better than the hand-calibrated CSPs in simulating these maize and soybean cultivars when using one time measurements, such as phenology dates, final dry matter yield, maximum leaf area index, and grain yield. For example, in the Prisma maize experiments in Zaragosa, Spain in 1995 and 1996, the average relative absolute error (RAE) values between the simulated and measured output variables were only 3 and 8%, respectively, while they were between 4 and 10% for hand-calibrated CSPs and above 16% for the default CSPs.
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    Feeding Africa’s soils: Fertilizer policy
    (2019) Joseph Rusike; Oumou Camara
    Fertilizer production and utilization in Africa are profoundly influenced by governmental policies at both national and regional levels. These policies have extensive ramifications across the fertilizer value chain, including finance availability, pricing, institutional arrangements, infrastructure development, and market dynamics. Despite substantial investments and policy efforts, Africa still faces challenges in achieving agricultural transformation through improved fertilizer use. This chapter explores the significance of policy and regulatory frameworks in shaping fertilizer industries, detailing policy formulation processes and implementation experiences across selected countries in Africa. It highlights the prevalence of subsidies as a key policy tool but also delves into the myriad challenges, including bureaucratic hurdles, financial constraints, market inefficiencies, and regulatory shortcomings. The chapter emphasizes the need for private sector involvement, market competitiveness, and policy reform to address these obstacles and enhance fertilizer accessibility, quality, and affordability for smallholder farmers. Furthermore, it examines the complexities of policy development and implementation, emphasizing the technical and political dimensions involved. The chapter concludes with insights into specific country experiences, offering a comprehensive overview of fertilizer policy landscapes, regulatory mechanisms, and ongoing challenges in Mali, Burkina Faso, Ghana, Nigeria, Ethiopia, Kenya, Tanzania, and Malawi.
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    Feeding Africa’s soils: Fertilizer subsidies
    (2019) Mahamadou Nassirou Ba; Marie Claire Kalihangabo; Joseph Rusike; Oumou Camara
    Fertilizer promotion programs in Africa have undergone significant evolution since their inception in the 1970s. Initially characterized by direct government expenditures and interventions to stimulate fertilizer demand and usage, these programs faced challenges of sustainability and effectiveness. Structural adjustment programs in the 1990s led to the discontinuation of many of these programs, only to witness a resurgence following the 2006 Abuja Declaration on Fertilizers. This resurgence saw the implementation of targeted subsidy programs across several African countries, aimed at increasing agricultural productivity. The phases of evolution encompassed top-down government management, liberalization, private sector expansion, and recent shifts towards market-based systems. Today, most sub-Saharan African countries have some form of subsidy program in place, albeit with varying degrees of government involvement and private sector participation. As governments transition towards regulatory roles, the focus is on improving subsidy program design, implementation, and performance. Smart subsidy programs, private sector involvement, investment in supporting infrastructure, and complementary measures are highlighted as key strategies for enhancing the effectiveness and sustainability of fertilizer subsidy programs in Africa.
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    Fertilizer in Kenya: Factors Driving the Increase in Usage by Smallholder Farmers
    (2011) Joshua Ariga; Thomas S. Jayne
    This chapter provides an overview of the factors driving the increase in fertilizer usage by smallholder farmers in Kenya, focusing on policy reforms and market dynamics. The narrative contrasts the historical context of state intervention in agriculture with the liberalization policies of the 1990s and their impact on fertilizer markets and maize production. It highlights the role of market infrastructure, government subsidies, and private sector involvement in shaping fertilizer access and usage. The analysis is based on data from household surveys and government reports covering the period from the late 1980s to the early 2010s.