| 1. |
- Hoffmann, M., et al.
(författare)
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Leaching of nitrogen in Swedish agriculture - A historical perspective
- 2000
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Ingår i: Agriculture, Ecosystems & Environment. - 0167-8809 .- 1873-2305. ; 80:3, s. 277-290
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Tidskriftsartikel (refereegranskat)abstract
- There is a need to examine long-term changes in nitrogen leaching from arable soils. The purpose of this study was to analyse variations in specific leaching rates (kg ha-1 per year) and gross load (Mg per year) of N from arable land to watercourses in Sweden from a historical perspective. The start of the study was set to 1865 because information on crop distribution, yield and livestock has been compiled yearly since then. The SOIL/SOILN model was used to calculate nitrogen leaching. Calculations were done for cereals, grass and bare fallow for three different soil types in nine agricultural regions covering a range of climatic conditions. Results indicate that both specific leaching rates and gross load of nitrogen in the middle of 19th century were approximately the same as they are today for the whole of south and central Sweden. Three main explanations for this were (1) large areas of bare fallow typical for the farming practice at the time, (2) enhanced mineralisation from newly cultivated land, and (3) low yield. From 1865, i.e. the start of the calculations, N leaching rates decreased and were at their lowest around 1930. During the same period, gross load was also at its lowest despite the fact that the acreage of arable land was at its most extensive. After 1930, average leaching increased by 60% and gross load by 30%, both reaching a peak in the mid-1970s to be followed by a declining trend. The greatest increase in leaching was in regions where the increase in animal density was largest and these regions were also those where the natural conditions for leaching such as mild winters and coarse-textured soils were found. Extensive draining projects occurred during the period of investigation, in particular an intensive exploitation of lakes and wetlands. This caused a substantial drop in nitrogen retention and the probable increase in net load to the sea might thus have been more affected by this decrease in retention than the actual increase in gross load. (C) 2000 Elsevier Science B.V.
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| 2. |
- Bisang, Irene, et al.
(författare)
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Three decades of field surveys reveal a decline of arable bryophytes in the Swiss lowlands despite agri-environment schemes
- 2021
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Ingår i: Agriculture, Ecosystems & Environment. Applied Soil Ecology. - : Elsevier BV. - 0929-1393 .- 1873-0272. ; 313
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Tidskriftsartikel (refereegranskat)abstract
- Agricultural intensification represents one of the major drivers for the dramatic loss of biodiversity worldwide. To halt the decline of farmland biodiversity, Switzerland adopted agri-environment schemes (AES) in 1998. Here, we monitored the occurrence, abundance and habitats of two species of arable bryophyte specialists, the Field hornwort (Anthoceros agrestis) and the Carolina hornwort (Phaeoceros carolinianus), in 28 crop fields in the intensively cultivated Swiss Plateau from 1991–2018, to investigate the effects of arable management, AES directives, and weather conditions on their performance. The target species are characteristic of the specialized short-lived arable bryophyte flora of Central Europe that depend on bare substrate in low-intensively cultivated and regularly ploughed fields. Trends in their occurrence thus reflect in many respects the status of the arable bryophytes in cultivated fields. Hornwort occurrence significantly declined between 1991 and 2018. A strong decrease in stubble fields that remain unmanaged after harvest, the favourite habitat for many arable specialists in the study area, largely accounted for the decline. Stubble fields nearly disappeared in the study area because of a gradual reduction in the cultivation area of cereals and the increasing practice of immediate post-harvest tillage. The latter is common in intensive arable farming and was accentuated by AES directives amended in 2005. Hornwort occurrences were positively affected by high air humidity during summer, but weather effects were subordinate to management effects. We propose tailored amendments of AES regulations, that aremented at selected sites, to maintain the characteristic arable specialist bryophytes in the Swiss Plateau: crop rotation with adequate proportions of cereals that are regularly ploughed but not before the end of October, no post-harvest processing of stubble fields, and optimization of the existing instrument ‘Biodiversity Promoting Areas’, e.g., short-term fallows in crop fields. Late-autumn or overwintering stubbles and short-term fallows will benefit many other organisms that depend on extensively managed open habitats, for example arableflowers, farmland breeding birds and specialized arthropods
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| 3. |
- Alexandridis, Nikolaos, et al.
(författare)
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Climate change and ecological intensification of agriculture in sub-Saharan Africa : A systems approach to predict maize yield under push-pull technology
- 2023
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Ingår i: Agriculture, Ecosystems and Environment. - 0167-8809 .- 1873-2305. ; 352
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Tidskriftsartikel (refereegranskat)abstract
- Assessing effects of climate change on agricultural systems and the potential for ecological intensification to increase food security in developing countries is essential to guide management, policy-making and future research. ‘Push-pull’ technology (PPT) is a poly-cropping design developed in eastern Africa that utilizes plant chemicals to mediate plant–insect interactions. PPT application yields significant increases in crop productivity, by reducing pest load and damage caused by arthropods and parasitic weeds, while also bolstering soil fertility. As climate change effects may be species- and/or context-specific, there is need to elucidate how, in interaction with biotic factors, projected climate conditions are likely to influence future functioning of PPT. Here, we first reviewed how changes in temperature, precipitation and atmospheric CO2 concentration can influence PPT components (i.e., land use, soils, crops, weeds, diseases, pests and their natural enemies) across sub-Saharan Africa (SSA). We then imposed these anticipated responses on a landscape-scale qualitative mathematical model of maize production under PPT in eastern Africa, to predict cumulative, structure-mediated impacts of climate change on maize yield. Our review suggests variable impacts of climate change on PPT components in SSA by the end of the 21st century, including reduced soil fertility, increased weed and arthropod pest pressure and increased prevalence of crop diseases, but also increased biological control by pests’ natural enemies. Extrapolating empirical evidence of climate effects to predict responses to projected climate conditions is mainly limited by a lack of mechanistic understanding regarding single and interactive effects of climate variables on PPT components. Model predictions of maize yield responses to anticipated impacts of climate change in eastern Africa suggest predominantly negative future trends. Nevertheless, maize yields can be sustained or increased by favourable changes in system components with less certain future behaviour, including higher PPT adoption, preservation of field edge density and agricultural diversification beyond cereal crops.
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| 4. |
- Alexandridis, Nikolaos, et al.
(författare)
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Climate change and ecological intensification of agriculture in sub-Saharan Africa – A systems approach to predict maize yield under push-pull technology
- 2023
-
Ingår i: Agriculture, Ecosystems & Environment. - 0167-8809 .- 1873-2305. ; 352
-
Tidskriftsartikel (refereegranskat)abstract
- Assessing effects of climate change on agricultural systems and the potential for ecological intensification to increase food security in developing countries is essential to guide management, policy-making and future research. ‘Push-pull’ technology (PPT) is a poly-cropping design developed in eastern Africa that utilizes plant chemicals to mediate plant–insect interactions. PPT application yields significant increases in crop productivity, by reducing pest load and damage caused by arthropods and parasitic weeds, while also bolstering soil fertility. As climate change effects may be species- and/or context-specific, there is need to elucidate how, in interaction with biotic factors, projected climate conditions are likely to influence future functioning of PPT. Here, we first reviewed how changes in temperature, precipitation and atmospheric CO2 concentration can influence PPT components (i.e., land use, soils, crops, weeds, diseases, pests and their natural enemies) across sub-Saharan Africa (SSA). We then imposed these anticipated responses on a landscape-scale qualitative mathematical model of maize production under PPT in eastern Africa, to predict cumulative, structure-mediated impacts of climate change on maize yield. Our review suggests variable impacts of climate change on PPT components in SSA by the end of the 21st century, including reduced soil fertility, increased weed and arthropod pest pressure and increased prevalence of crop diseases, but also increased biological control by pests’ natural enemies. Extrapolating empirical evidence of climate effects to predict responses to projected climate conditions is mainly limited by a lack of mechanistic understanding regarding single and interactive effects of climate variables on PPT components. Model predictions of maize yield responses to anticipated impacts of climate change in eastern Africa suggest predominantly negative future trends. Nevertheless, maize yields can be sustained or increased by favourable changes in system components with less certain future behaviour, including higher PPT adoption, preservation of field edge density and agricultural diversification beyond cereal crops.
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| 5. |
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| 6. |
- Andersson, Georg, et al.
(författare)
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Effects of farming intensity, crop rotation and landscape heterogeneity on field bean pollination
- 2014
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Ingår i: Agriculture, Ecosystems & Environment. - : Elsevier BV. - 1873-2305 .- 0167-8809. ; 184, s. 145-148
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Tidskriftsartikel (refereegranskat)abstract
- Organic farming has the potential to enhance ecosystem services such as crop pollination. However, it is not known if a similar effect can be generated on conventional farms, without reducing external inputs such as inorganic fertilizers and pesticides, by using more complex crop rotations including ley for animal fodder production. In two separate designs, both located in southern Sweden, we tested if local organic farming and the landscape proportion of conventionally managed leys, along a landscape heterogeneity gradient, affected the pollination success of field bean. The number of developed pods was higher on organic farms compared to conventional ones. Development of beans, which demands high pollination efficiency, increased with increasing landscape heterogeneity, but only on organic farms. Increasing proportion of ley on conventional farms did not significantly influence the development of beans. The number of developed pods was not affected by the proportion of ley in the landscape. Our results demonstrate that in order to maximize pollination success it is important to improve both field management and preserve semi-natural habitats in the agricultural landscape. Reducing farming intensity with conventionally managed leys does not seem to be as effective as organic farming for delivering crop pollination services. (C) 2013 Elsevier B.V. All rights reserved.
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| 7. |
- Audet, Joachim, et al.
(författare)
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Nitrous oxide emissions from streams in a Swedish agricultural catchment
- 2017
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Ingår i: Agriculture, Ecosystems & Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 236, s. 295-303
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Tidskriftsartikel (refereegranskat)abstract
- Excess nitrogen fertiliser in agricultural soils might be leached to streams and converted to the greenhouse gas nitrous oxide (N2O). To assess the importance of N2O emissions from agricultural streams, concentration dynamics and emissions N2O emissions in streams were investigated in a 32 km2 lowland agricultural catchment located in Sweden. Dissolved N2O concentration was measured at nine occasions between December 2014 and August 2015 at nine stream stations. The stream stations represented sub-catchments with different land use characteristics with agricultural land use ranging from 0 to 63% of the area. Stream N2O percentage saturation ranged 40-2701% and showed large spatial and temporal variations. Statistical analysis using mixed models revealed that N2O concentration was significantly linked to nitrate concentration in the stream water, to the percentage arable land in the sub catchments as well as to the stream water discharge. Using two empirical equations to estimate the N2O emissions showed that streams were generally a source of N2O to the atmosphere (mean 108 and 175 mu g N m(-2) h(-1) with first and second equation). The catchment scale estimate of N2O stream emissions was compared to the estimate obtained using IPCC guidelines linking N fertilisation inputs and leaching to N2O emissions. The comparison suggested that N2O stream emission calculated using the IPCC methodology might be underestimated. A coarse estimate suggests that N2O stream emissions represent about 4% of the total N2O emissions from N-fertiliser at the catchment scale. Hence while streams covered only 0.1% of the catchment area they were of disproportionate importance as a source of N2O to the atmosphere.
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| 8. |
- Bahram, Mohammad
(författare)
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Cropping systems with higher organic carbon promote soil microbial diversity
- 2021
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 319
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Tidskriftsartikel (refereegranskat)abstract
- Food systems need to become more sustainable. There is a need to investigate the agricultural management components that address the sustainability better. Long crop rotations are suggested to be environmentally friendly, yet, little is known how soil microbial communities may be affected by long-term rotation under organic cropping with cover crops and manure and conventional cropping with different nitrogen rates. We examined the composition and diversity of soil bacterial and fungal communities in a five-field crop rotation at the beginning and end, respectively in 2013 and 2018. Our analysis revealed that bacterial and to a lesser extent fungal diversity increased by the end of the rotation in all organic treatments and in conventional treatments with low to medium nitrogen rate (20‐100 kg of nitrogen per hectare). Conventional treatment with no added nitrogen decreased bacterial and fungal diversity. Nitrogen rate of 150 kg/ha decreased only bacterial diversity, while the impact on fungal diversity was neutral. Crop rotation significantly increased the relative abundance of bacterial taxa involved in nitrification and denitrification. Of fungal functional groups, the relative abundance of pathogenic functional groups decreased and mycorrhizal groups increased during crop rotation and especially with added cover crops. Our results suggest that crop rotation may outperform cropping systems in structuring soil microbial communities.
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| 9. |
- Benegas, Laura, et al.
(författare)
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Effects of trees on infiltrability and preferential flow in two contrasting agroecosystems in Central America
- 2014
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 183, s. 185-196
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Tidskriftsartikel (refereegranskat)abstract
- We tested the hypothesis that trees have measurable effects on infiltrability, macroporosity, and preferential flows in agrosilvopastoral systems. Managing agricultural systems for water conservation is a critical component of sustainable systems. We investigated the relationship between infiltrability and the distance to the nearest tree, and whether differences in macroporosity can account for differences in infiltrability.In both systems, preferential soil water flows were dominant compared to matrix flow. Trees in the pasture landscape improved infiltrability and preferential flow but had no significant effect in the coffee agroforestry system. After comparing rainfall intensity and frequency data to the measured infiltrability values, we conclude that trees in the pasture system reduce surface runoff at the highest observed rainfall intensities (>50 mm h(-1)). The volcanic soils of the coffee plantation are less degraded and their high natural permeability has been maintained. Since the coffee plants at this site are established (40 years) perennial vegetation with substantial residues and extensive root systems like trees, they improve soil physical properties similarly to trees.Trees increase hydrologic services in pasture lands, a rapidly expanding land use type across Latin America, and therefore may be a viable land management option for mitigating some of the negative environmental impacts associated with land clearing and animal husbandry. However, in land management practices where understorey perennial vegetation makes up a large proportion of the cover, such as for coffee agroforestry systems, the effect of trees on infiltration-related ecosystem services could be less pronounced (C) 2013 Elsevier B.V. All rights reserved.
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| 10. |
- Berg, Åke, et al.
(författare)
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Linking occurrence and changes in local abundance of farmland bird species to landscape composition and land-use changes
- 2015
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 204, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Changes in agricultural policies have caused dramatic changes in land-use in agricultural landscapes. To investigate whether such changes in land-use relate to temporal changes in bird communities a repeated inventory (1994 and 2004) of farmland birds was made in 212 point-count sites in south-central Sweden.Distinct changes in abundance of several species over the study period were recorded, abundance of the 16 studied species decreased by 23%. The decline was significant for eight species, while two species increased significantly. Persistence and colonisation models suggested similar species-habitat relationships as the snapshot models, i.e. eight of the 12 associations were in line with what could be expected from the snapshot models. Occurrence of nine species was linked to land-use whereas six species displayed links between changes in occurrence and changes in land-use. In line with previous studies positive effects of short rotation coppice and negative effects of autumn-sown crops were found, while set-asides showed fewer effects than expected. In the snapshot models several species showed links to landscape characteristics such as amount of forest (negative for five species) and landscape heterogeneity (positive for six species). The evidence for effects of the landscape variables on persistence/colonisation was more restricted.The results suggest that both land-use changes and the landscape setting may cause local changes in abundance of farmland birds, even for species displaying a general decline in numbers between years, the effects of land-use changes being, however, strongly species specific. (C) 2014 Elsevier B.V. All rights reserved.
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| 11. |
- Berndes, Göran, 1966, et al.
(författare)
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Cadmium accumulation and Salix-based phytoextraction on arable land in Sweden
- 2004
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 103:1, s. 207-223
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Tidskriftsartikel (refereegranskat)abstract
- Cadmium accumulation in arable soils causes concern due to possible direct environmental effects and health risks associated with exposure of humans to cadmium through agricultural products. This paper discusses the problem of cadmium accumulation in Swedish arable land, and evaluates Salix (Salix vinimalis) cultivation as a tool for addressing the problem. It is found that Salix cultivation offers an effective option for addressing the cadmium accumulation, especially when the topsoil has high cadmium content due to anthropogenic inflows, and the subsoil naturally contains little cadmium. The estimated practical potential for Salix-based cadmium management (ca. 490 000 ha) is very large compared to the present Salix plantation area in Sweden (ca. 15 000 ha). However, the estimates of the net economic value of cadmium removal from arable land indicate that the economics of Salix production will not improve dramatically due to an induced cadmium removal. Salix-based cadmium management will therefore most likely take place in counties where Salix cultivation can be expected to expand as a response to an unfilled biomass demand in the energy sector. © 2003 Elsevier B.V. All rights reserved.
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| 12. |
- Birkhofer, Klaus, et al.
(författare)
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The contribution of CAP greening measures to conservation biological control at two spatial scales
- 2018
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809. ; 255, s. 84-94
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Tidskriftsartikel (refereegranskat)abstract
- To promote a more sustainable agricultural production, the European Commission implemented direct payments that require farmers to implement greening measures aimed at reducing negative effects of agriculture on the environment and biodiversity. These greening measures (including fallows and permanent grasslands) have been criticised for their potential inability to conserve biodiversity and promote associated ecosystem services. In this study, we investigate if the presence of old or recently established fallows and permanent grassland in the landscape are beneficial for the emergence, activity density and spillover of ground-running natural enemies and as a result aphid biological control in cereal fields. Lycosidae and Theridiidae were more numerous in fallows (emergence & activity density) compared to crop fields, while Staphylinidae and Linyphiidae showed opposite patterns. Spillover of Lycosidae was significantly higher from fallows into cereal fields, than between cereal fields. As a result of the opposite patterns in activity density in fallows between different groups of predators, a spillover from fallows did not result in a significantly higher aphid control in crop fields adjacent to them. A high proportion of permanent grassland in the landscape resulted in lower emergence of Linyphiidae and Carabidae. Our results support the assumption that a higher emergence and activity density of ground-running predators generally results in higher spillover to adjacent fields. However, patterns of emergence and activity density differed between individual natural enemy groups. Fallows, independent of age, can therefore act as source or sink depending on the focal predator group and more permanent grassland in the landscape can result in lower local emergence. Fallows at the local scale and permanent grassland at larger spatial scales therefore did not generally promote aphid biological control services provided by ground-running natural enemies.
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| 13. |
- Blanchet, Guillaume, et al.
(författare)
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Responses of soil properties and crop yields to different inorganic and organic amendments in a Swiss conventional farming system
- 2016
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Ingår i: Agriculture, Ecosystems & Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 230, s. 116-126
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Tidskriftsartikel (refereegranskat)abstract
- In agro-ecosystems, fertilization practices are crucial for sustaining crop productivity. Here, based on a 50-year long-term experiment, we studied the influence of fertilization practices (inorganic and/or organic) and nitrogen (N) application rates on (i) soil physicochemical properties, (ii) microbial and earthworm communities and (iii) crop production. Our results showed that soil organic carbon content was increased by incorporation of crop residues (+2.45%) and farmyard manure application (+6.40%) in comparison to the use of mineral fertilizer alone. In contrast, soil carbon stock was not significantly affected by these fertilization practices. Overall, only farmyard manure application improved soil physicochemical properties compared to mineral fertilization alone. Soil microbial population was enhanced by the application of organic amendments as indicated by microbial biomass and phospholipid-derived fatty acids contents. The fertilization practices and the N application rates affected significantly both the biomass and composition of earthworm populations, especially the epigeic and endogeic species. Finally, farmyard manure application significantly increased crop yield (+3.5%) in comparison to mineral fertilization alone. Crop residue incorporation rendered variable but similar crop yields over the 50-year period. The results of this long-term experiment indicate that the use of organic amendments not only reduces the need for higher amount of mineral N fertilizer but also improves the soil biological properties with direct effects on crop yield.
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| 14. |
- Blanke, Jan Hendrik, et al.
(författare)
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Assessing the impact of changes in land-use intensity and climate on simulated trade-offs between crop yield and nitrogen leaching
- 2017
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809. ; 239, s. 385-398
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Tidskriftsartikel (refereegranskat)abstract
- In this study, a global vegetation model (LPJ-GUESS) is forced with spatial information (Nomenclature of Units for Territorial Statistics (NUTS) 2 level) of land-use intensity change in the form of nitrogen (N) fertilization derived from a model chain which informed the Common Agricultural Policy Regionalized Impact (CAPRI) model. We analysed the combined role of climate change and land-use intensity change for trade-offs between agricultural yield and N leaching in the European Union under two plausible scenarios up until 2040. Furthermore, we assessed both driver importance and uncertainty in future trends based on an alternative land-use intensity dataset derived from an integrated assessment model. LPJ-GUESS simulated an increase in wheat and maize yield but also N leaching for most regions when driven by changes in land-use intensity and climate under RCP 8.5. Under RCP 4.5, N leaching is reduced in 53% of the regions while there is a trade-off in crop productivity. The most important factors influencing yield were CO2 (wheat) and climate (maize), but N application almost equaled these in importance. For N leaching, N application was the most important factor, followed by climate. Therefore, using a constant N application dataset in the absence of future projections has a substantial effect on simulated ecosystem responses, especially for maize yield and N leaching. This study is a first assessment of future N leaching and yield responses based on projections of climate and land-use intensity. It further highlights the importance of accounting for changes in future N applications and land-use intensity in general when evaluating environmental impacts over long time periods.
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| 15. |
- Boeraeve, Margaux
(författare)
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Cascading effects of management and landscape on insect pollinators, pollination services and yield in apple orchards
- 2023
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Ingår i: Agriculture, Ecosystems and Environment. - 0167-8809 .- 1873-2305. ; 352
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Tidskriftsartikel (refereegranskat)abstract
- Recent insect pollinator declines, mainly due to the expansion and intensification of agricultural land use, are jeopardizing ecosystem service provisioning in agroecosystems. Organic farming has been suggested as a biodiversity-friendly alternative to conventional farming, but additional insights evaluating its effectiveness in perennial cropping systems are needed. Here, we provide a comprehensive analysis of local and landscape effects on the provided pollination services and yield in apple crops. We first used mixed models to disentangle effects of agricultural management and landscape effects on both taxonomic and functional diversity of wild bees and hoverflies during bloom in both organic and integrated pest management (IPM) apple orchards in Belgium, and then compared these biodiversity indicators with semi-natural grasslands as a benchmark. Next, we applied piecewise structural equation modeling to quantify the direct and indirect effects of orchard management type and landscape on fruit set, seed set and ultimately on crop yield. Orchards, regardless of their type of man-agement, hosted lower taxonomic and functional pollinator diversity compared to the semi-natural benchmark. Yet, pollinator abundance and diversity were higher in orchard edges and increased with small-scale landscape diversity, which was positively associated with the presence of semi-natural habitat, as well as arable and urban land. Investigating the cascading effects on apple yield, we found that yield levels were not shaped by the observed pollinator diversity or by the measured pollination services, but were lower in organic orchards. Overall, we conclude that apple yield was likely not pollinator limited in our study system, but that conserving and restoring semi-natural habitats, maintaining and expanding orchard edges through reducing field sizes and promoting landscape diversity are the most promising avenues for pollinator conservation in orchard landscapes.
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| 16. |
- Bolinder, Martin, et al.
(författare)
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Long-term soil organic carbon and nitrogen dynamics in forage-based crop rotations in Northern Sweden (63-64 degrees N)
- 2010
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 138, s. 335-342
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Tidskriftsartikel (refereegranskat)abstract
- For carbon sequestration estimates it is necessary to evaluate effects of management practices on soil organic carbon (SOC) and nitrogen (SON) dynamics in a wide range of production systems and climatic zones. At higher latitudes with cold temperate climate, crop rotations dominated by forage are common and often highly productive-and the climate as well as the forage cropping systems favour large stocks of SOC and SON. The objective of this study was to estimate SOC and SON stock dynamics in the arable layer (0-25 cm) for different 6-year forage-based rotations using sampling data from three long-term field experiments in Northern Sweden. At the site with the lowest initial amount of SOC (8.2 kg C m(-2)), SOC stocks increased by 12 g C m(-2) yr(-1) over a 50-year period for the continuous forage rotation ('A'), which received ca. 10 Mg ha(-1) of cattle manure per year (wet mass). At the same site, SOC stocks were more or less at steady state in rotation 'B' with 4 years of forage and 2 years of annuals, receiving the same amount of manure. For rotation 'C' with 3 years of forage and receiving ca. 6.5 Mg ha(-1) of manure, the SOC stocks decreased by 18 g C m(-2) yr(-1,) while the SOC stocks for rotation 'D' with only annuals and no manure application decreased by 24 g C m(-2) yr(-1). At the other two sites, with higher initial SOC stocks (12.1 and 12.8 kg C m(-2)), the SOC stocks in all treatments decreased during a 30-year period, at a rate ranging from 11 to 95 g C m(-2) yr(-1). Similar trends were found for the change in SON stocks, although they were more variable. The topsoil SOC stocks were high compared to southern Sweden and regions of similar climate in northeast Canada, in particular for rotation A. These results indicate that the estimates of SOC and SON storage rate changes for a particular management system van vary widely within a small region of a given climatic zone. (C) 2010 Elsevier B.V. All rights reserved.
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| 17. |
- Bommarco, Riccardo
(författare)
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Landscape context and habitat type as drivers of bee diversity in European annual crops
- 2009
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 133, s. 40-47
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Tidskriftsartikel (refereegranskat)abstract
- To better understand the dynamics of bee populations in crops, we assessed the effect of landscape context and habitat type on bee communities in annual entomophilous crops in Europe. We quantified bee communities in five pairs of crop-country: buckwheat in Poland, cantaloupe in France, field beans in the UK, spring oilseed rape in Sweden, and strawberries in Germany. For each country, 7-10 study fields were sampled over a gradient of increasing proportion of semi-natural habitats in the surrounding landscape. The CORINE land cover classification was used to characterize the landscape over a 3 km radius around each study field and we used multivariate and regression analyses to quantify the impact of landscape features on bee abundance and diversity at the sub-generic taxonomic level. Neither overall wild bee abundance nor diversity, taken as the number of sub-genera. was significantly affected by the proportion of semi-natural habitat. Therefore, we used the most precise level of the CORINE classification to examine the possible links between specific landscape features and wild bee communities. Bee community composition fell into three distinct groups across Europe: group I included Poland, Germany, and Sweden, group 2 the UK, and group 3 France. Among all three groups, wild bee abundance and sub-generic diversity were affected by 17 landscape elements including some semi-natural habitats (e.g., transitional wood land-shrub), some urban habitats (e.g., sport and leisure facilities) and some crop habitats (e.g., non-irrigated arable land). Some bee taxa were positively affected by urban habitats only, others by semi-natural habitats only, and others by a combination of semi-natural, urban and crop habitats. Bee sub-genera favoured by urban and crop habitats were more resistant to landscape change than those favoured only by semi-natural habitats. In agroecosystems, the agricultural intensification defined as the loss of semi-natural habitats does not necessarily cause a decline in evenness at the local level, but can change community composition towards a bee fauna dominated by common taxa. (C) 2009 Elsevier B.V. All rights reserved.
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| 18. |
- Bommarco, Riccardo, et al.
(författare)
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Long-term trends in functional crop diversity across Swedish farms
- 2023
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 343
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Tidskriftsartikel (refereegranskat)abstract
- The diversity of cultivated crops is relevant on various spatial scales, from the field and farm to the landscape. We apply a decomposition of the Shannon diversity index that allows the differentiation of functional diversity of production. The decomposition separates diversity of functional crop groups from related diversity, which shows the species diversity within the crop groups. Using population-based field and farm-level data from Sweden 2001–2018, we are able to study the development of overall (Shannon), functional and related crop diversity among a total of 83770 farms. Crop diversity indices are calculated by farm and year based on the Swedish Land Parcel Identification system (LPIS). We find that functional crop diversity has declined among Swedish farms over the period. Related crop diversity has declined but regained in recent years. Accounting for farm size and pedoclimatic conditions, organic farms have a higher functional diversity, and the uptake of organic practices leads to an increase in functional crop diversity over the period.
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| 19. |
- Broberg, Malin, 1989, et al.
(författare)
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Effects of ozone, drought and heat stress on wheat yield and grain quality
- 2023
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Ingår i: Agriculture, Ecosystems & Environment. - 0167-8809. ; 352:15
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Tidskriftsartikel (refereegranskat)abstract
- Tropospheric ozone (O3) is a gaseous phytotoxic plant stressor known to reduce wheat (Triticum aestivum) crop yields at current concentrations. O3 is predicted to increase in many crop-growing regions, together with higher frequencies of heatwaves and droughts. In this study, wheat crops were exposed to two levels of O3 (ambient and ~70 ppb) in combination with ambient or elevated temperature (+8 ◦C) and two watering regimes (well-watered and 50% reduced water supply) during the grain-filling period. With this experimental setup, we assessed the interactive effects between O3, temperature and water supply on wheat yield and grain quality, and measured leaf gas exchange to explore the underlying mechanisms. Overall, O3, warming and drought all decreased grain yield and average grain mass but increased grain concentration of N and other nutrient elements. Increasing daytime O3 from 25 to 73 ppb resulted in a 25% yield reduction in treatments with ambient temperature and well-watered soil. Drought reduced the impact of O3 on light-saturated photosynthesis, grain mass, total aboveground biomass and grain concentrations of K, Ca, Mg, Mo. In contrast, concentrations of K and Ca increased to a larger extent when O3 stress was combined with elevated temperature. Grain concentrations of N, Ca and Zn were closely and negatively related to grain yield regardless of O3, heat and drought stress, likely explained by the reduction in grain filling period, with starch accumulation reduced to a larger extent than that of these elements. P, K, Mg, Mn, Mo concentrations were weakly related to grain yield, but were clearly altered by environmental stress. The modifying effect of water availability is crucial to include in assessments of O3 impacts on global food production in relation to climate change, considering effects on wheat yield variables and grain nutrient concentrations.
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| 20. |
- Bundschuh, Mirco
(författare)
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Runoff of veterinary pharmaceuticals from arable and grassland-A comparison between predictions from model simulations and experimental studies
- 2016
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 218, s. 33-39
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Tidskriftsartikel (refereegranskat)abstract
- Veterinary pharmaceuticals (VPs) are routinely used in livestock breeding. As a consequence, high concentrations of such VPs can be found in liquid manure, which is often applied to arable crops and grassland. From the soil, the VPs may enter surface water bodies via edge-of-field runoff, representing a potential risk to aquatic ecosystems. In the present study, the worst-case runoff predictions obtained by the FOCUS step 3 modeling approach, which is recommended for environmental-risk assessment of VPs in Europe, were compared with fate data obtained from experimental plot studies involving both arable and grassland plots. Five VPs were selected comprising three sulfonamides (sulfadiazine, sulfadimidine, sulfamethoxazole) and two benzimidazoles (fiubendazole, fenbendazole). The respective concentrations in runoff were initially estimated using literature data for model parameterization. Subsequently, the scenarios were parameterized specifically for each experimental plot study performed, enabling a direct comparison of the model performance with the close-to-field relevant situation.Generally, substantial variations between the predicted and measured concentrations of VPs in the runoff were uncovered. Although the FOCUS prediction suggested higher concentrations than were actually measured in 65% of the cases, the runoff concentrations of VPs were underestimated in the remaining 35%. This frequent underestimation of runoff concentrations was primarily observed for the grassland plots (85% of the underestimated situations), whereas the FOCUS predictions largely overestimated the measured concentrations for the arable plots. More strikingly, when involving a difference between the measured and predicted concentrations of 10% as a validity criterion for the model, only one (out of a total of 17) runoff concentration among the five VPs (i.e., sulfadimidine) assessed in the seven scenarios fell within this tolerance margin. Thus, these results demonstrate the substantial uncertainties related to the use of the FOCUS surface water modeling approach for the prediction of VPs introduced with manure and their environmental risk. (C) 2015 Elsevier B.V. All rights reserved.
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| 21. |
- Burra, Dharani, et al.
(författare)
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Soil fertility regulates invasive herbivore performance and top-down control in tropical agroecosystems of Southeast Asia
- 2017
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 249, s. 38-49
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Tidskriftsartikel (refereegranskat)abstract
- In terrestrial ecosystems, changes in soil nutrient availability, plant growth or natural enemies can generate important shifts in abundance of organisms at various trophic levels. In agroecosystems the performance of (invasive) herbivores and their impacts on crops is of particular concern. Scientists are presently challenged with making reliable inferences on invader success, natural enemy performance and efficacy of biological control, particularly in tropical agroecosystems. In this study, we assess how trophic regulatory forces (bottom-up vs. top down) influence the success of three globally important pests of cassava. We examine the mealybug species (Hemiptera: Pseudococcidae) of differing host breadth and invasion history: Phenacoccus manihoti, Paracoccus marginatus, and Pseudococcus jackbeardsleyi. Potted plant fertilizer trials were combined with a regional survey in Vietnam, Laos and Cambodia of 65 cassava fields of similar size and age, but with varying soil fertility. Relative abundance of each mealybug invader was mapped along a soil fertility gradient, and contrasted with site-specific measures of parasitism. Potted plant trials revealed strong bottom-up effects for P. manihoti, such that impacts of nitrogen and potassium additions were propagated through to higher trophic levels and substantially boost development and fitness of its specialist parasitoid, Anctgyrus lopezi (Hymenoptera: Encyrtidae). Field surveys indicate that mealybug performance is highly species-specific and context-dependent. For example, field-level abundance of P. jackbeardsleyi and P. marginatus, was related to measures of soil fertility parameters, soil texture and plant disease incidence. Furthermore, for P. manihoti, in-field abundance is equally associated with soil texture (i.e., silt content). Principal component analysis (PCA) and regression suggested that P. manihoti and P. marginatus are disproportionately favored in low-fertility conditions, while P. jackbeardsleyi prospers in settings with high organic carbon and phosphorus. Parasitism of P. manihoti by A. lopezi varied greatly with field and soil fertility conditions, and was highest in soils with intermediate fertility levels and where management practices include the addition of fertilizer supplements. Our characterization of the relative performance of invasive mealybugs and strength of parasitism across variable soil fertility conditions will help guide parasitoid release programs and soil management practices that enhance mealybug biological control.
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| 22. |
- Börjesson, Gunnar
(författare)
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Thresholds of target phosphorus fertility classes in European fertilizer recommendations in relation to critical soil test phosphorus values derived from the analysis of 55 European long-term field experiments
- 2022
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 332
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Tidskriftsartikel (refereegranskat)abstract
- Phosphorus (P) fertilizer recommendations of individual countries may differ in many aspects, but often the main principle is to reach or maintain a target range of plant-available P in soil. Within this target P fertility class, the soil is expected to supply enough P to the crop, while P fertilization replaces what is exported by the harvested crop. However, the threshold values of the target P fertility classes are based on a multitude of different soil test P (STP) methods and vary by a factor of up to three, even for countries using the same STP method. This study aimed to provide a comparison of the thresholds of target P fertility classes of different European countries and critical soil test P values (P-crit; STP below which the average relative yield falls below 95% due to P insufficiency) derived from the analysis of data from 55 long-term field experiments in eight European countries. To overcome the issue of diverging STP methods, all values were converted to Olsen-P using empirically based conversion equations from the literature. Converted threshold values varied by a factor of up to five. For the experimental data, we fitted multi-level Mitscherlich-type models to determine P(crit )values of unfertilized soils corresponding to 95% of maximum yield. We found an average Olsen-P-crit value of 15 mg P kg(-1) (adj. R-2 = 0.37; RMSE = 14.1% relative yield; n = 2368; 55 experiments), which lies far below several country-specific thresholds of target P fertility classes. Crop-specific analyses resulted in higher Olsen-P(crit )values for sugar beet (22 mg P kg-( 1)), potato (19 mg P kg (-1)) and winter rapeseed (18 mg P kg (-1)). Among the texture classes (loam, sand, silt and clay), sandy soils exhibited the highest average Olsen-P(crit )value (22 mg P kg( -1)). We consider a reevaluation of extraordinarily high country-specific thresholds as well as an inclusion of crop type and soil texture (where not already implemented) to be a reasonable measure towards more cost-effective and environment-friendly P fertilization.
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| 23. |
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| 24. |
- Chala, Workneh Bedada, et al.
(författare)
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Long-term addition of compost and NP fertilizer increases crop yield and improves soil quality in experiments on smallholder farms
- 2014
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 195, s. 193-201
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Tidskriftsartikel (refereegranskat)abstract
- Soil fertility decline due to low nutrient input is a constraint for sustainable agriculture in smallholder farming systems in Ethiopia. In this study, crop productivity and soil organic matter buildup were compared in soils receiving locally made compost, applied either alone or in combination with NP fertilizer. The experiments had four treatments: full dose of compost (C), full dose of fertilizer (F), half compost and half fertilizer (CF), and unfertilized control (control). The full dose of compost was equivalent to 2.4 t ha(-1) organic matter. The field study was conducted on four farm fields in the village Beseku, each representing different sub-villages. Participating farmers were selected based on their willingness and an assessment of dedication to carry out the experiment. The experiments, a randomized complete block design with three replications, were replicated across four farm fields. The treatments were repeated for six cropping seasons (years), and data on soil nutrient status and crop (maize, wheat, potato, and faba bean) harvests were collected. In the 0-10 cm soil layer, pH was (P < 0.05) lower in the F treatments than in the C and CF treatments. Compared with the F treatment, the soil organic carbon (SOC) and total nitrogen stocks increased (P < 0.05) by 4.60 and 0.42 t ha(-1) in C treatment, and by 4.74 and 0.45 t ha(-1) in CF treatment. Treatment effects on crop harvests were significant (P < 0.05) for all crops grown across the sites and seasons. The highest maize yield was obtained from CF, with relative harvest of 178% compared with the control and 126% compared with F, but was comparable to C. For wheat and potato, the yields obtained from CF, C and F were comparable. For faba bean, CF had a relative harvest of 145% over the control. Maize harvest was in the order of CF > F> C> control in the initial season, CF > C> F> control in the next three consecutive seasons, and C> CF> F> control in the final year of the experiment. The overall combined yield was in the order of CF > C> F> control for maize and faba bean, CF > F> C> control for potato, and F> CF > C> control for wheat. The addition of either compost alone or in combination with NP fertilizer improved soil properties and crop productivity, compared with control and only fertilizer addition. Therefore, compost addition can serve as a complement to fertilizer use and reduce dependence on mineral fertilizer in low-input crop production system. The apparent synergy between compost and fertilizer addition needs further research in order to be explained. (C) 2014 Elsevier B.V. All rights reserved.
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| 25. |
- Chala, Workneh Bedada, et al.
(författare)
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Soil nutrient build-up, input interaction effects and plot level N and P balances under long-term addition of compost and NP fertilizer
- 2016
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 218, s. 220-231
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Tidskriftsartikel (refereegranskat)abstract
- Decline in farmland soil fertility due to nutrient depletion is a concern for smallholder farmers in the highlands of Ethiopia. In this study we tested if long-term addition of compost, either alone or in combination with nitrogen (N) and phosphorous (P) fertilizer, affected available soil nutrient status, grain/tuber harvests, agronomic N use efficiency, and plot level N and P nutrient balances. The on-farm experiments were conducted on four farm fields for up to 6 years in Beseku, Ethiopia. A randomized complete block design was used, with four treatments: full dose of compost applied alone at 2.4 t ha(-1) DW organic matter (C); full dose of fertilizer (F); half compost and half fertilizer (CF); and, unfertilized control. In the upper 10 cm of the surface soil, several Mehlich-3 extractable nutrients (B, Ca, K, Mg, P, S, and Zn) had significantly higher concentrations in the C treatment (P < 0.01), and some in the CF treatment (P < 0.05) than in the control. Phosphorus was the only nutrient with a higher concentration in the F treatment than the control. Maize and faba bean showed added benefits (synergy) in terms of yield increase in the CF treatment and a better agronomic efficiency for added N. Plot level N balances were negative for all treatments except C, with strong depletion in the control (-76 kg N ha(-1) yr(-1)) and F (-65 kg N ha(-1) yr(-1)) treatments. When the N balance was compared to measured change in soil N, the F and control treatments were significantly (P < 0.05) lower than zero. N in the CF and C treatments was close to steady-state, i.e., the input of N in organic matter compensated for the loss of N through mineralization. The control treatment had a negative P balance of 11 kg P ha(-1) yr(-1), with moderately negative balance of 4 kg P ha(-1) yr(-1) in the C treatment. The CF and F treatments had positive P balances. Thus, the addition of compost, both alone or in combination with mineral fertilizer, can prevent N and reduce P mining and improve the nutrient status of the soil. When only NP fertilizer was used, the crop utilized all N that was mineralized indicating that the crop was N limited. (C) 2015 Elsevier B.V. All rights reserved.
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