| 1. |
- Tyler, Torbjörn, et al.
(författare)
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Climate warming and land-use changes drive broad-scale floristic changes in Southern Sweden
- 2018
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013. ; 24:6, s. 2607-2621
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Tidskriftsartikel (refereegranskat)abstract
- Land-use changes, pollution and climate warming during the 20th century havecaused changes in biodiversity across the world. However, in many cases, the environmental drivers are poorly understood. To identify and rank the drivers currentlycausing broad-scale floristic changes in N Europe, we analysed data from two vascularplant surveys of 200 randomly selected 2.5 9 2.5 km grid-squares in Scania,southernmost Sweden, conducted 1989–2006 and 2008–2015, respectively, andrelated the change in frequency (performance) of the species to a wide range ofspecies-specific plant traits. We chose traits representing all plausible drivers ofrecent floristic changes: climatic change (northern distribution limit, flowering time),land-use change (light requirement, response to grazing/mowing, response to soildisturbance), drainage (water requirement), acidification (pH optimum), nitrogendeposition and eutrophication (N requirement, N fixation ability, carnivory, parasitism,mycorrhizal associations), pollinator decline (mode of reproduction) andchanges in CO2 levels (photosynthetic pathway). Our results suggest that climatewarming and changes in land-use were the main drivers of changes in the flora duringthe last decades. Climate warming appeared as the most influential driver, withnorthern distribution limit explaining 30%–60% of the variance in the GLMM models.However, the relative importance of the drivers differed among habitat types,with grassland species being affected the most by cessation of grazing/mowing andspecies of ruderal habitats by on-going concentration of both agriculture and humanpopulation to the most productive soils. For wetland species, only pH optimum wassignificantly related to species performance, possibly an effect of the increasinghumification of acidic water bodies. An observed relative decline of mycorrhizal species may possibly be explained by decreasing nitrogen deposition resulting in lesscompetition for phosphorus. We found no effect of shortage or decline of pollinatinglepidopterans and bees.
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| 2. |
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| 3. |
- Ekroos, Johan, et al.
(författare)
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Sparing land for biodiversity at multiple spatial scales
- 2016
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Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media SA. - 2296-701X. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- A common approach to the conservation of farmland biodiversity and the promotion of multifunctional landscapes, particularly in landscapes containing only small remnants of non-crop habitats, has been to maintain landscape heterogeneity and reduce land-use intensity. In contrast, it has recently been shown that devoting specific areas of non-crop habitats to conservation, segregated from high-yielding farmland (“land sparing”), can more effectively conserve biodiversity than promoting low-yielding, less intensively managed farmland occupying larger areas (“land sharing”). In the present paper we suggest that the debate over the relative merits of land sparing or land sharing is partly blurred by the differing spatial scales at which it is suggested that land sparing should be applied. We argue that there is no single correct spatial scale for segregating biodiversity protection and commodity production in multifunctional landscapes. Instead we propose an alternative conceptual construct, which we call “multiple-scale land sparing,” targeting biodiversity and ecosystem services in transformed landscapes. We discuss how multiple-scale land sparing may overcome the apparent dichotomy between land sharing and land sparing and help to find acceptable compromises that conserve biodiversity and landscape multifunctionality.
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| 4. |
- Hydbom, Sofia, et al.
(författare)
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The use of conservation tillage in an agro-intensive region : results from a survey of farmers in Scania, Sweden
- 2020
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Ingår i: Renewable Agriculture and Food Systems. - 1742-1705. ; 35:1, s. 59-68
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Tidskriftsartikel (refereegranskat)abstract
- Conventional agricultural practices can lead to soil erosion and a reduction in soil organic carbon (SOC) content. It has been suggested that less intensive agricultural practices, such as conservation tillage (including no-till and reduced till without soil inversion) may reduce both erosion and loss of SOC. The aim of this study was to determine whether, and why, conservation tillage is used in Scania, which is one of the most agro-intensive regions in Sweden. We also investigated how information on tillage practices is obtained, why one type of tillage may be favored over another, and whether some farmers are more likely to use conservation tillage. The result of this study will benefit policy makers and researchers by pinpointing factors that influence the use of conservation tillage. To collect data, a questionnaire was sent to farmers in Scania in 2016. We found that the majority of the responding farmers used conservation tillage, and that it was more likely to be used if the farmer was highly educated and spent more than 50% of their annual working time on crop production. The use of conservation tillage was also more common if the farm was large and clay soil dominated. Crop rotation was often highlighted as the most important factor influencing the choice of tillage practice, which may be due to crop species requirements. When asked to compare the consequences of reduced tillage and plowing, the perception of farmers using conservation tillage was in general more positive, indicating skepticism toward the practice of reduced tillage until it had been tried. We show that the use of conservation tillage, sometimes in combination with plowing, is widespread in Scania. However, unless changes in, for example, crop rotation and labor requirements occur, the use of conservation tillage will most likely remain the same as today, or only increase slightly in the near future. Farm enlargement may result in an increased conservation tillage use, and so may efforts to educate advisors, increased opportunities for peer-to-peer meetings, and the development of economically viable small farm solutions. Increased conservation tillage may be part of the solution for sustainable crop production, but drawbacks such as increased pesticide use must be addressed further, as well as factors such as crop rotation development and practical knowledge that influence conservation tillage use at the farm level.
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| 5. |
- Olsson, Ola, et al.
(författare)
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Phosphorus and carbon availability regulate structural composition and complexity of AM fungal mycelium.
- 2014
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Ingår i: Mycorrhiza. - : Springer Science and Business Media LLC. - 1432-1890 .- 0940-6360. ; 24:6, s. 443-451
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Tidskriftsartikel (refereegranskat)abstract
- The regulation of the structural composition and complexity of the mycelium of arbuscular mycorrhizal (AM) fungi is not well understood due to their obligate biotrophic nature. The aim of this study was to investigate the structure of extraradical mycelium at high and low availability of carbon (C) to the roots and phosphorus (P) to the fungus. We used monoxenic cultures of the AM fungus Rhizophagus irregularis (formerly Glomus intraradices) with transformed carrot roots as the host in a cultivation system including a root-free compartment into which the extraradical mycelium could grow. We found that high C availability increased hyphal length and spore production and anastomosis formation within individual mycelia. High P availability increased the formation of branched absorbing structures and reduced spore production and the overall length of runner hyphae. The complexity of the mycelium, as indicated by its fractal dimensions, increased with both high C and P availability. The results indicate that low P availability induces a growth pattern that reflects foraging for both P and C. Low C availability to AM roots could still support the explorative development of the mycelium when P availability was low. These findings help us to better understand the development of AM fungi in ecosystems with high P input and/or when plants are subjected to shading, grazing or any management practice that reduces the photosynthetic ability of the plant.
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| 6. |
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| 7. |
- Aliasgharzad, Nasser, et al.
(författare)
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Acidification of a sandy grassland favours bacteria and disfavours fungal saprotrophs as estimated by fatty acid profiling
- 2010
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Ingår i: Soil Biology & Biochemistry. - : Elsevier BV. - 0038-0717. ; 42:7, s. 1058-1064
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Tidskriftsartikel (refereegranskat)abstract
- We have investigated the structure of a microbial community in semi-natural sandy grassland in southeast Sweden. The sand is rich in lime, but in most places the soil is decalcified in the upper layers, and therefore this site shows a large variation in pH within short distances. We collected samples at three different soil depths (0-10 cm, 10-20 cm and 20-30 cm) and found the pH to range from 5 to 8 in the topsoil and from 4.5 to 9.5 in the deepest layer. The abundance of saprophytic fungi and bacteria was investigated using signature phospholipid fatty acids and arbuscular mycorrhizal fungi (AMF) using the neutral lipid fatty acid 16:1 omega 5. The PLFA pattern of the topsoil was different from that in the other two layers, as indicated by principal component analysis. The saprotrophic fungi were associated with high pH, and bacteria with low pH in these sandy soils. No relation was found between pH and AMF in the topsoil, while a positive relation was found in the deepest soil layer. The saprophytic fungi-to-bacteria ratio was constant with depth, while the AMF-to-bacteria ratio increased with soil depth. The results showed that high soil pH favoured fungal saprophytes in sandy grasslands and that AMF are relatively more abundant than the other two groups in deeper soil layers: particularly so when the pH is high. (C) 2010 Elsevier Ltd. All rights reserved.
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| 8. |
- Aliasgharzad, Nasser, et al.
(författare)
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Lack of arbuscular mycorrhizal colonisation in tea (Camellia sinensis L.) plants cultivated in Northern Iran
- 2011
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Ingår i: Symbiosis. - : Springer Science and Business Media LLC. - 0334-5114 .- 1878-7665. ; 55:2, s. 91-95
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Tidskriftsartikel (refereegranskat)abstract
- Soil and roots associated with different tea clones and nearby weeds (Veronica sp., Setaria sp., Salvia sp., Senecio sp. and Tripogon sp.) were sampled for arbuscular mycorrhizal fungi (AMF) in the tea gardens of Northern Iran. Spores were searched for in the soil and AMF colonisation determined microscopically and fatty acid signatures in roots was determined. Root samples from mycorrhizal and non-mycorrhizal clover were used as positive and negative controls. AMF spores were abundant in the tea garden soils; the genera Glomus and Acaulospora dominated. Microscopic observations of stained tea roots showed no sign of AMF. To confirm this, the roots were analysed for fatty acid signature compounds. The average level of PLFA 16:1 omega 5 as signature molecule for AMF in tea roots was 2 nmol g(-1) dry root, while the NLFA 16: 1 omega 5 was not detectable. In mycorrhizal and non-mycorrhizal clover roots, the PLFA 16:1 omega 5 was 141 and 5.74 nmol g(-1) dry root, respectively. In roots of weeds in tea plantations, the amount of PLFA 16:1 omega 5 was in the range 4.9 to 31.1 nmol g(-1) dry root. Thus, there was no evidence for AMF association in tea roots and weeds are thought to be the source of the spores in the soils. Finally, no mycorrhizal colonisation was found when tea plant seedlings were inoculated with AMF in pot cultures.
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| 9. |
- Antonsen, H, et al.
(författare)
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Relative importance of burning, mowing and species translocation in the restoration of a former boreal hayfield: responses of plant diversity and the microbial community
- 2005
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Ingår i: Journal of Applied Ecology. - : Wiley. - 1365-2664 .- 0021-8901. ; 42:2, s. 337-347
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Tidskriftsartikel (refereegranskat)abstract
- 1. The extensive loss of species-rich grasslands in Europe as a result of agricultural intensification has triggered a desire to recreate more diverse and natural grassland systems in set-aside fields. Appropriate management and species introductions are necessary to overcome residual soil fertility, lack of suitable plant propagules and dominance of undesirable invasive species. 2. A field experiment was performed in a boreal former hayfield to test the effect of turf inoculation, mowing (twice annually) and spring burning. We surveyed changes in plant diversity, composition and productivity over a 3-year period. Signature fatty acids and soil respiration measurements were employed to survey changes in the soil community. 3. Few changes in the vegetation and soil communities could be related to inoculation of turf monoliths. Most of the measured variables in mown plots differed from the set-aside (control) plots, while burned plots displayed mainly similar responses. Mowing increased plant species richness and diversity, mainly by enhancing the number and frequency of forb species. Small-statured forb species were promoted by mowing, whereas tall leafy grasses declined. Effects of mowing on soil communities comprised an increased soil respiration and stimulation of arbuscular mycorrhizal fungi. 4. Synthesis and applications. The results demonstrate the importance of reducing sward height in order to promote plant species coexistence in former boreal hayfields. In such systems, eliminating accumulated litter by spring burning has little influence on species composition when the sward is allowed to grow tall. Mowing is therefore the most efficient way of enhancing biodiversity. The results also show that mowing-mediated changes in above-ground plant communities may stimulate below-ground symbiotic micro-organisms, potentially resulting in a positive feedback on ecosystem development.
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| 10. |
- Bahr, Adam, et al.
(författare)
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Long-term changes in vegetation and soil chemistry in a calcareous and sandy semi-natural grassland
- 2012
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Ingår i: Flora: Morphology, Distribution, Functional Ecology of Plants. - : Elsevier BV. - 0367-2530. ; 207:5, s. 379-387
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Tidskriftsartikel (refereegranskat)abstract
- Calcicole plant species are vulnerable to acidification and fertilization, caused by deposition and changes in land use, since they are adapted to nutrient-poor calcareous conditions. In this study we used vegetation data (vascular plants, bryophytes and lichens) from 1964 and 1985 and stored soil samples from 1966 to investigate long-term soil chemistry and vegetation changes in a semi-natural, sandy calcareous grassland in southern Sweden. In the re-investigation in 2008 we found that increased decalcification due to acidification could not be verified. The plant community had changed from stress-tolerant calcareous grassland towards a community promoted by higher nutrient availability. Furthermore, the cover of species indicating calcareous conditions had decreased. A decline in the cover of species adapted to alkaline, phosphorus-poor conditions may be due to increased nutrient availability, but there were also indications that the vegetation had changed due to overgrowth by woody plants. This long-term impoverishment of the plant community highlights the need for appropriate management of calcareous grasslands, in order to limit the nutrients available in the soil and prevent overgrowth by shrubs and trees. (C) 2012 Published by Elsevier GmbH.
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