| 1. |
- Bargaz, Adnane
(författare)
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Agroforestry promotes soybean yield stability and N-2-fixation under water stress
- 2015
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 35, s. 1541-1549
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Tidskriftsartikel (refereegranskat)abstract
- Agroforestry systems can buffer crop performance against the impacts of climate change, particularly decreases in the availability of soil water. Nonetheless, farmers are reluctant to adopt agroforestry systems due to concerns of yield losses, predominantly in the tree-crop competitive zone. Yet little is known about crop performance in the tree-crop competitive zone under water limited conditions. We therefore studied the effect of a full season water deficit on soybean N-2-fixation, nodulation, and yield in the tree-crop zone of a mature agroforestry system. We hypothesized higher N-2-fixation yet lower but stable yield in the tree-crop zone. Rainfall reduction shelters were used to reduce available soil moisture throughout the growing season in the tree-crop competitive zone of a 27-year-old tree-based intercropping agroforestry system and a paired monoculture control plot in southern Ontario, Canada. Results show that soybean yields in the tree-crop zone were lower compared to monoculture. However, soybean yields were stable in agroforestry and only in monoculture did the rainfall reduction induce a significant decline in soybean yields. Soybeans in the tree-crop zone relied heavily on N-2-fixation to meet N demand, with a percentage of N derived from atmosphere (%Ndfa) of 91 % versus 63 % in monoculture. However, total fixed N declined significantly under rainfall reduction in both the tree-crop zone and in monoculture. Of note, soybean nodulation patterns adapted to soil moisture availability, allocating a larger proportion of nodules lower on the rooting system under water limitation. Our results demonstrate that important N pathways may be altered under water limitation. We can also expect that in areas where growing conditions are predicted to become drier in the future, yields in the tree-crop competitive zone will not be reduced further, thus increasing the viability of adopting agroforestry systems in areas affected by climatic change.
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| 2. |
- Caron, Patrick, et al.
(författare)
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Food systems for sustainable development : proposals for a profound four-part transformation
- 2018
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 38:4
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Forskningsöversikt (refereegranskat)abstract
- Evidence shows the importance of food systems for sustainable development: they are at the nexus that links food security, nutrition, and human health, the viability of ecosystems, climate change, and social justice. However, agricultural policies tend to focus on food supply, and sometimes, on mechanisms to address negative externalities. We propose an alternative. Our starting point is that agriculture and food systems' policies should be aligned to the 2030 Agenda for Sustainable Development. This calls for deep changes in comparison with the paradigms that prevailed when steering the agricultural change in the XXth century. We identify the comprehensive food systems transformation that is needed. It has four parts: first, food systems should enable all people to benefit from nutritious and healthy food. Second, they should reflect sustainable agricultural production and food value chains. Third, they should mitigate climate change and build resilience. Fourth, they should encourage a renaissance of rural territories. The implementation of the transformation relies on (i) suitable metrics to aid decision-making, (ii) synergy of policies through convergence of local and global priorities, and (iii) enhancement of development approaches that focus on territories. We build on the work of the Milano Group, an informal group of experts convened by the UN Secretary General in Milan in 2015. Backed by a literature review, what emerges is a strategic narrative linking climate, agriculture and food, and calling for a deep transformation of food systems at scale. This is critical for achieving the Sustainable Development Goals and the Paris Agreement. The narrative highlights the needed consistency between global actions for sustainable development and numerous local-level innovations. It emphasizes the challenge of designing differentiated paths for food systems transformation responding to local and national expectations. Scientific and operational challenges are associated with the alignment and arbitration of local action within the context of global priorities.
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| 3. |
- Dahlin, Sigrun
(författare)
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Yield and labor relations of sustainable intensification options for smallholder farmers in sub-Saharan Africa. A meta-analysis
- 2019
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 39
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Tidskriftsartikel (refereegranskat)abstract
- Sustainable intensification of agricultural production is needed to ensure increased productivity relative to inputs. Short-term yield returns and labor input are major determinants of the fate of sustainable intensification options on smallholder farms in sub-Saharan Africa because labor shortage is often acute, and most farmers lack access to labor-saving technologies. We assessed the relationship between maize grain yield change and labor input from a total of 28 published papers (631 data pairs) including subsets of data pairs within specific sustainable intensification practices. Among the reviewed technologies, manually dug planting basins showed ratios between the change in yield and change in labor inputs (Y/L) below 1, suggesting that labor demand increased more than yield. In contrast, ridging showed average Y/L values 2. No-till showed high Y/L (average1.7) when combined with herbicides but average Y/L 1 (total labor) when manually weeded. Manually weeded rotations showed average Y/L 1 and manually weeded intercropping systems average Y/L around 1. The relations revealed four scenarios: high yield returns but low labor demand, high yield returns and labor demand, low yield returns and labor demand, and low yield returns but high labor demand. High yield with high labor demand requires mostly investments in machinery and/or herbicides to reduce labor input. Low yield with low labor demand requires improved crop management, whereas low yield with high labor demand requires a combination of improved crop management and investments to reduce labor. This is the first comprehensive assessment showing that the sustainable intensification options being considered for smallholder farmers may increase crop yield but also labor demand. Options that include mechanization and herbicides at low cost are likely to be adopted due to their reduction effect on drudgery and total labor input.
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| 4. |
- Jensen, Erik Steen
(författare)
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Ecological principles underlying the increase of productivity achieved by cereal-grain legume intercrops in organic farming. A review
- 2015
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 35, s. 911-935
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Forskningsöversikt (refereegranskat)abstract
- World population is projected to reach over nine billion by the year 2050, and ensuring food security while mitigating environmental impacts represents a major agricultural challenge. Thus, higher productivity must be reached through sustainable production by taking into account climate change, resources rarefaction like phosphorus and water, and losses of fertile lands. Enhancing crop diversity is increasingly recognized as a crucial lever for sustainable agro-ecological development. Growing legumes, a major biological nitrogen source, is also a powerful option to reduce synthetic nitrogen fertilizers use and associated fossil energy consumption. Organic farming, which does not allow the use of chemical, is also regarded as one prototype to enhance the sustainability of modern agriculture while decreasing environmental impacts. Here, we review the potential advantages of eco-functional intensification in organic farming by intercropping cereal and grain legume species sown and harvested together. Our review is based on a literature analysis reinforced with integration of an original dataset of 58 field experiments conducted since 2001 in contrasted pedo-climatic European conditions in order to generalize the findings and draw up common guidelines. The major points are that intercropping lead to: (i) higher and more stable grain yield than the mean sole crops (0.33 versus 0.27 kg m(-2)), (ii) higher cereal protein concentration than in sole crop (11.1 versus 9.8 %), (iii) higher and more stable gross margin than the mean sole crops (702 versus 577 a,not signaEuro parts per thousand ha(-1)) and (iv) improved use of abiotic resources according to species complementarities for light interception and use of both soil mineral nitrogen and atmospheric N-2. Intercropping is particularly suited for low-nitrogen availability systems but further mechanistic understanding is required to propose generic crop management procedures. Also, development of this practice must be achieved with the collaboration of value chain actors such as breeders to select cultivars suited to intercropping.
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| 5. |
- Karlsson, Johan, et al.
(författare)
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Designing a future food vision for the Nordics through a participatory modeling approach
- 2018
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 38
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Tidskriftsartikel (refereegranskat)abstract
- The development of future food systems will depend on normative decisions taken at different levels by policymakers and stakeholders. Scenario modeling is an adequate tool for assessing the implications of such decisions, but for an enlightened debate, it is important to make explicit and transparent how such value-based decisions affect modeling results. In a participatory approach working with five NGOs, we developed a future food vision for the Nordic countries (Denmark, Finland, Norway and Sweden) through an iterative process of defining the scenario, modeling, and revising the scenario, until a final future food vision was reached. The impacts on food production, land use, and greenhouse gas emissions, and the resulting diets in the food vision, were modeled using a mass flow model of the food system. The food vision formulated was an organic farming system where food is produced locally and livestock production is limited to leftover streams, i.e., by-products from food production and forage from pastures and perennial grass/clover mixtures, thus limiting food-feed competition. Consumption of meat, especially non-ruminant meat, was substantially reduced compared with current consumption in the Nordic countries (-81%). An estimated population of 37 million people could be supplied with the scenario diet, which uses 0.21ha of arable land and causes greenhouse gas emissions of 0.48 tCO(2)e per diet and year. The novelty of this paper includes advancing modeling of sustainable food systems by using an iterative process for designing future food visions based on stakeholder values, which enables results from multidisciplinary modeling (including agronomy, environmental system analysis, animal and human nutrition) to be fed back into the decision-making process, providing an empirical basis for normative decisions and a science-based future vision of sustainable food systems.
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| 6. |
- Kuyah, Shem, et al.
(författare)
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Agroforestry delivers a win-win solution for ecosystem services in sub-Saharan Africa. A meta-analysis
- 2019
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 39
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Tidskriftsartikel (refereegranskat)abstract
- Agricultural landscapes are increasingly being managed with the aim of enhancing the provisioning of multiple ecosystem services and sustainability of production systems. However, agricultural management that maximizes provisioning ecosystem services can often reduce both regulating and maintenance services. We hypothesized that agroforestry reduces trade-offs between provisioning and regulating/maintenance services. We conducted a quantitative synthesis of studies carried out in sub-Saharan Africa focusing on crop yield (as an indicator of provisioning services), soil fertility, erosion control, and water regulation (as indicators of regulating/maintenance services). A total of 1106 observations were extracted from 126 peer-reviewed publications that fulfilled the selection criteria for meta-analysis of studies comparing agroforestry and non-agroforestry practices (hereafter control) in sub-Saharan Africa. Across ecological conditions, agroforestry significantly increased crop yield, total soil nitrogen, soil organic carbon, and available phosphorus compared to the control. Agroforestry practices also reduced runoff and soil loss and improved infiltration rates and soil moisture content. No significant differences were detected between the different ecological conditions, management regimes, and types of woody perennials for any of the ecosystem services. Main trade-offs included low available phosphorus and low soil moisture against higher crop yield. This is the first meta-analysis that shows that, on average, agroforestry systems in sub-Saharan Africa increase crop yield while maintaining delivery of regulating/maintenance ecosystem services. We also demonstrate how woody perennials have been managed in agricultural landscapes to provide multiple ecosystem services without sacrificing crop productivity. This is important in rural livelihoods where the range of ecosystem services conveys benefits in terms of food security and resilience to environmental shocks.
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| 7. |
- Lalander, Cecilia, et al.
(författare)
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High waste-to-biomass conversion and efficient Salmonella spp. reduction using black soldier fly for waste recycling
- 2015
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 35, s. 261-271
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Tidskriftsartikel (refereegranskat)abstract
- The recycling of organic waste worldwide is not effective, which leads to water pollution and loss of potential crop fertilizers. Available resources have to be used more efficiently as the world population increases. An innovative solution is to use insects for the management of organic waste. Here, we used black soldier fly to convert organic waste into animal feed protein, as fly larvae, and plant fertilizer, as compost residue. A continuous fly reactor was monitored for 9 weeks. We analyzed physicochemical and microbial parameters, and we evaluated the sanitary risk. Results show 55.1 % of material degradation and 11.8 % of biomass conversion based upon total solids. We observed higher levels of N and P in the treatment residue than in the inflow material. Results also show a lower concentration of Salmonella spp. and viruses. Compost treatment with black soldier fly is therefore an efficient system for nutrient recycling.
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| 8. |
- Lana, Marcos
(författare)
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Yield stability and lower susceptibility to abiotic stresses of improved open-pollinated and hybrid maize cultivars
- 2017
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 37
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Tidskriftsartikel (refereegranskat)abstract
- Maize is one of the world's most important cereals, cultivated in a wide range of environments. Besides the importance of maize and the gains in yield from selection schemes, commercial breeding drastically reduced the number of cultivars of this crop. Current common sense states that hybrids, when compared to open-pollinated cultivars, are a better adaptation strategy to cope with the impacts of climate change. However, the performance and resilience of cultivars with different levels of improvement are still not explored in this context. Four cultivars-a commercial hybrid, one commercially improved open-pollinated, one improved open-pollinated derived from participatory breeding, and one from a farmer's selection-were tested using the CERES-Maize crop model. Field experiments conducted in Brazil were used for calibration and evaluation. Synthetic scenarios of climate change resulted from the application of the incremental method on historical series of observations (30 years), with temperature increments ranging from +0.5 up to +3.0 degrees C and precipitation changes from -30 up to +30%. Planting dates consisted in nine dates (August 1-December 1, each 15 days). Results demonstrate that the model could mimic the phenology and yield of two improved open-pollinated cultivars (MPA01 and Fortuna) and the hybrid (AS1548). One open-pollinated cultivar could not be validated due to its high phenotypic variability. Yield response surfaces showed distinct impacts among cultivars, with improved open-pollinated cultivar MPA01 having a higher yield stability when compared to the hybrid. Early planting dates produced lower yields with higher risk of crop failure for all cultivars. Late planting dates produced higher yields with higher failure risk. Considering risk and yield, the best planting window for all cultivars and scenarios is between September and October. Our results demonstrate, for the first time, that improved open-pollinated cultivars are equivalent or more resilient than hybrids to yield changes under different scenarios of abiotic stresses.
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| 9. |
- Reckling, Moritz, et al.
(författare)
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Grain legume decline and potential recovery in European agriculture: a review
- 2016
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 36
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Forskningsöversikt (refereegranskat)abstract
- Sustainable development of agriculture is at the core of agricultural policy debates in Europe. There is a consensus that diversification of cropping would support sustainable development. However, a reduction in legume cultivation has been observed in the EU during the last decades. This decline has induced, in turn, a deficit of proteins and a reduction of ecosystem services provided by legumes. Therefore, we analysed the mechanisms that shape agricultural systems to identify leverage points for reviving European legume production. Specifically, we reviewed the factors that affect the market and non-market value of legumes and the relevant agricultural policies. We characterized the decline in legume cropping as an outcome of the dominance of economic forces that favour specialization of production systems over diversification. We found that the value of market outputs of legumes per unit area is relatively low and volatile, with a 25-78 % variation in pea gross margins, which reduces market competitiveness. We observed that the value of system-internal outputs of legumes such as the nitrogen fixed, of 130 to 153 kg N ha(-1); crop protection services that reduce agrochemical costs, by 20-25% in cereals; and yield enhancements of subsequent crops, of 0.2 to 1.6 t ha(-1) in cereals, are often underestimated. In addition, markets fail to translate external effects of legumes such as biodiversity enhancement, reduction in emissions, of up to 50 % in N2O, and soil improvements into economic benefits. Current policies support legumes through selected mechanisms such as ecological focus areas, agri-environmental programmes and sparse coupled support measures. Domestic cultivation of legumes could be supported through trade policies such as import restrictions on genetically modified soybean or new mechanisms to appreciate non-market outputs including payments for ecosystem services and carbon markets. In addition, development of new value chains, niche markets, scaling-up of plant breeding efforts and dissemination of information is required.
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| 10. |
- Reckling, Moritz, et al.
(författare)
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Grain legume yields are as stable as other spring crops in long-term experiments across northern Europe
- 2018
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Ingår i: Agronomy for Sustainable Development. - : Springer Science and Business Media LLC. - 1774-0746 .- 1773-0155. ; 38
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Tidskriftsartikel (refereegranskat)abstract
- Grain legumes produce high-quality protein for food and feed, and potentially contribute to sustainable cropping systems, but they are grown on only 1.5% of European arable land. Low temporal yield stability is one of the reasons held responsible for the low proportion of grain legumes, without sufficient quantitative evidence. The objective of this study was to compare the yield stability of grain legumes with other crop species in a northern European context and accounting for the effects of scale in the analysis and the data. To avoid aggregation biases in the yield data, we used data from long-term field experiments. The experiments included grain legumes (lupin, field pea, and faba bean), other broad-leaved crops, spring, and winter cereals. Experiments were conducted in the UK, Sweden, and Germany. To compare yield stability between grain legumes and other crops, we used a scale-adjusted yield stability indicator that accounts for the yield differences between crops following Taylor's Power Law. Here, we show that temporal yield instability of grain legumes (30%) was higher than that of autumn-sown cereals (19%), but lower than that of other spring-sown broad-leaved crops (35%), and only slightly greater than spring-sown cereals (27%). With the scale-adjusted yield stability indicator, we estimated 21% higher yield stability for grain legumes compared to a standard stability measure. These novel findings demonstrate that grain legume yields are as reliable as those of other spring-sown crops in major production systems of northern Europe, which could influence the current negative perception on grain legume cultivation. Initiatives are still needed to improve the crops agronomy to provide higher and more stable yields in future.
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