41 research outputs found

    Identifying changes in agricultural practices and policy interventions for sustainable intensification of farm systems in southern Mali

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    Achieving sustainable development goals for smallholder rural populations within the next eleven years is challenging: besides environmental and climate pressures, rising rural population and unfavorable institutional arrangements diminish the room to manoeuvre within the current system’s settings. New farming practices and progressive policies to trigger and support drastic changes are needed. A large array of innovative farming practices have been developed across sub-Saharan Africa (e.g. Snapp et al., 2010). Our objective was to grasp the scale of the challenge: what is the potential of changes in farm practices to improve farming sustainability in southern Mali, a region that is representative for land-scarce sub-Saharan Africa?Which policies are needed to support sustainable development

    Fertilizer and Soil Health in Africa The Role of Fertilizer in Building Soil Health to Sustain Farming and Address Climate Change

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    Summary Soil health is commonly defined as the ability to generate sufficient crop yields while maintaining the future productive capacity of soils and the ecosystem services soils regulate and deliver. However, less consensus exists on indicators to assess soil health and its changes over time and space, although soil organic carbon (SOC) is generally acknowledged as a key indicator. In the context of this paper, soil health status is equated with SOC status. Current SOC conditions are influenced by soil properties and climate. Under smallholder farming conditions, SOC is variable and affected by past crop and soil management practices, which are influenced by farmer typology. Although SOC content under cropland is a maximum of 60-70% of that under natural vegetation, there is substantial scope to increase it in smallholder farming conditions. A conceptual framework relating to fertilizer, crop productivity, and soil health is presented here. While fertilizer application commonly results in a substantial increase in crop yield at various scales, a key indicator of fertilizer use, agronomic efficiency (AE), is often observed to be lower than relatively easily achievable values under well-managed conditions, caused by a diversity of factors. Low AE values do not necessarily result in greater greenhouse gas (GHG) emissions because of the low fertilizer application rates in sub-Saharan Africa (SSA), though increases in GHG emissions are likely with increases in fertilizer use. Crop response to organic inputs is substantially lower although organic inputs increase SOC content, which usually results in greater AE values relative to sole application of fertilizer. Increases in crop productivity are associated with increases in SOC, though the relationship is weak and efforts besides fertilizer application itself are required. That said, N(PK) fertilizer has had a positive effect on SOC in most parts of the world except SSA, an observation corroborated by an analysis of past and ongoing long-term experiments, likely related to the low and erratic use of fertilizer in the region. While fertilizer use can be an entry point to increasing soil health, this will not likely happen on degraded soils where responses to fertilizer are limited. In such cases, investments to rehabilitate degraded soils should come first. Several approaches can be followed to determine best fertilizer recommendations, while recognizing nutrients needs by crops and soil-specific properties. Site-specificity commonly requires an assessment of the soil fertility status of a particular field, and analytical tools now allow for the development of locally relevant recommendations at scale with some early successes. While organic inputs do positively impact SOC, attractive options to increase organic inputs in smallholder farming systems are limited and mostly related to in-situ production, with an important emphasis on multi-purpose legumes. Climate adaptation is facilitated by healthy Fertilizer and Soil Health in Africa 2 soils and requires fertilizer to be combined with other crop, soil, and water management practices (Wortmann and Stewart, 2021). While low yields are linked to the ecological yield gap, whereby the potential productivity of crops is set by biological factors, input and output prices determine the economic yield gap, which is usually quite lower than the former because of unfavourable ratio of fertilizer prices to crop product prices. Even though profitability is a key driver of impact, many other factors affect the adoption of appropriate fertilizer and soil health recommendations, including farmers’ production objectives, resource endowment, land tenure, and access to markets. A main bottleneck in engaging smallholder farmers in soil health-restoring practices is the relatively large amount of time such practices take to deliver benefits that are visible to farmers. In the absence of incentive programs, farmers require short-term benefits, generated within their farming systems. Furthermore, associated advice on complementary practices to fertilizer use increases the complexity of information to be conveyed to farmers. Scaling models have moved toward the delivery of bundled services, often digitally enabled, to address challenges with communicating complex information and the necessary complementary crop and soil management practices. Targeted policy interventions can support the delivery of broad digitally enabled fertilizer management recommendations and the creation of conditions that enable smallholder farmers to implement these recommendations at scale. A number of recommendations have been generated from the scientific information, covered under the following headings: (1) key elements of a Fertilizer and Soil Health Action Plan; (2) development of quantitative indicators and targets of soil health; (3) addressing climate change requires choices; (4) incentivizing farmers; (5) soil health investments, which require localized actions (think global, act local); and (6) not only fertilizers, but also auxiliary interventions, as defined by the Integrated Soil Fertility Management (ISFM) approach. Action is needed today to reverse the downward spiral of low and inefficient fertilizer use, resulting in low yields and declining soil health

    The input reduction principle of agroecology is wrong when it comes to mineral fertilizer use in sub-Saharan Africa

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    Can farmers in sub-Saharan Africa (SSA) boost crop yields and improve food availability without using more mineral fertilizer? This question has been at the center of lively debates among the civil society, policy-makers, and in academic editorials. Proponents of the “yes” answer have put forward the “input reduction” principle of agroecology, i.e. by relying on agrobiodiversity, recycling and better efficiency, agroecological practices such as the use of legumes and manure can increase crop productivity without the need for more mineral fertilizer. We reviewed decades of scientific literature on nutrient balances in SSA, biological nitrogen fixation of tropical legumes, manure production and use in smallholder farming systems, and the environmental impact of mineral fertilizer. Our analyses show that more mineral fertilizer is needed in SSA for five reasons: (i) the starting point in SSA is that agricultural production is “agroecological” by default, that is, very low mineral fertilizer use, widespread mixed crop-livestock systems and large crop diversity including legumes, but leading to poor soil fertility as a result of widespread soil nutrient mining, (ii) the nitrogen needs of crops cannot be adequately met solely through biological nitrogen fixation by legumes and recycling of animal manure, (iii) other nutrients like phosphorus and potassium need to be replaced continuously, (iv) mineral fertilizers, if used appropriately, cause little harm to the environment, and (v) reducing the use of mineral fertilizers would hamper productivity gains and contribute indirectly to agricultural expansion and to deforestation. Yet, the agroecological principles directly related to soil fertility—recycling, efficiency, diversity—remain key in improving soil health and nutrient-use efficiency, and are critical to sustaining crop productivity in the long run. We argue for a nuanced position that acknowledges the critical need for more mineral fertilizers in SSA, in combination with the use of agroecological practices and adequate policy support

    Establishing the reliability and validity of the Zagazig Depression Scale in a UK student population: an online pilot study

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    Background: It is thought that depressive disorders will be the second leading cause of disability worldwide by 2020. Recently, there is a steady increase in the number of university students diagnosed and treated as depression patients. It can be assumed that depression is a serious mental health problem for university students because it affects all age groups of the students either younger or older equally. The current study aims to establish the reliability and validity of the Zagazig Depression scale in a UK sample. Methods: The study was a cross-sectional online survey. A sample of 133 out of 275 undergraduate students from a range of UK Universities in the academic year 2008-2009, aged 20.3 ± 6.3 years old were recruited. A modified back translated version of Zagazig Depression scale was used. In order to validate the Zagazig Depression scale, participants were asked to complete the Patient Health Questionnaire. Statistical analysis includes Kappa analysis, Cronbach's alpha, Spearman's correlation analysis, and Confirmatory Factor analysis. Results: Using the recommended cut-off of Zagazig Depression scale for possible minor depression it was found that 30.3% of the students have depression and higher percentage was identified according to the Patient Health Questionnaire (37.4%). Females were more depressed. The mean ZDS score was 8.3 ± 4.2. Rates of depression increase as students get older. The reliability of The ZDS was satisfactory (Cronbach's alpha was .894). For validity, ZDS score was strongly associated with PHQ, with no significant difference (p-value > 0.05), with strong positive correlation (r = +.8, p-value < 0.01). Conclusion: The strong, significant correlation between the PHQ and ZDS, along with high internal consistency of the ZDS as a whole provides evidence that ZDS is a reliable measure of depressive symptoms and is promising for the use of the translated ZDS in a large-scale cross-culture study
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