1. |
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2. |
- Crous, P. W., et al.
(author)
-
Fusarium : more than a node or a foot-shaped basal cell
- 2021
-
In: Studies in mycology. - : CENTRAALBUREAU SCHIMMELCULTURE. - 0166-0616 .- 1872-9797. ; :98
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Journal article (peer-reviewed)abstract
- Recent publications have argued that there are potentially serious consequences for researchers in recognising distinct genera in the terminal fusarioid clade of the family Nectriaceae. Thus, an alternate hypothesis, namely a very broad concept of the genus Fusarium was proposed. In doing so, however, a significant body of data that supports distinct genera in Nectriaceae based on morphology, biology, and phylogeny is disregarded. A DNA phylogeny based on 19 orthologous protein-coding genes was presented to support a very broad concept of Fusarium at the F1 node in Nectriaceae. Here, we demonstrate that re-analyses of this dataset show that all 19 genes support the F3 node that represents Fusarium sensu stricto as defined by F. sambucinum (sexual morph synonym Gibberella pulicaris). The backbone of the phylogeny is resolved by the concatenated alignment, but only six of the 19 genes fully support the F1 node, representing the broad circumscription of Fusarium. Furthermore, a re-analysis of the concatenated dataset revealed alternate topologies in different phylogenetic algorithms, highlighting the deep divergence and unresolved placement of various Nectriaceae lineages proposed as members of Fusarium. Species of Fusarium s. str. are characterised by Gibberella sexual morphs, asexual morphs with thin- or thick-walled macroconidia that have variously shaped apical and basal cells, and trichothecene mycotoxin production, which separates them from other fusarioid genera. Here we show that the Wollenweber concept of Fusarium presently accounts for 20 segregate genera with clear-cut synapomorphic traits, and that fusarioid macroconidia represent a character that has been gained or lost multiple times throughout Nectriaceae. Thus, the very broad circumscription of Fusarium is blurry and without apparent synapomorphies, and does not include all genera with fusarium-like macroconidia, which are spread throughout Nectriaceae (e.g., Cosmosporella, Macroconia, Microcera). In this study four new genera are introduced, along with 18 new species and 16 new combinations. These names convey information about relationships, morphology, and ecological preference that would otherwise be lost in a broader definition of Fusarium. To assist users to correctly identify fusarioid genera and species, we introduce a new online identification database, Fusarioid-ID, accessible at www.fusarium.org. The database comprises partial sequences from multiple genes commonly used to identify fusarioid taxa (act1, CaM, his3, rpb1, rpb2, tef1, tub2, ITS, and LSU). In this paper, we also present a nomenclator of names that have been introduced in Fusarium up to January 2021 as well as their current status, types, and diagnostic DNA barcode data. In this study, researchers from 46 countries, representing taxonomists, plant pathologists, medical mycologists, quarantine officials, regulatory agencies, and students, strongly support the application and use of a more precisely delimited Fusarium (= Gibberella) concept to accommodate taxa from the robust monophyletic node F3 on the basis of a well-defined and unique combination of morphological and biochemical features. This F3 node includes, among others, species of the F. fujikuroi, F. incarnatum-equiseti, F. oxysporum, and F. sambucinum species complexes, but not species of Bisifusarium [F. dimerum species complex (SC)], Cyanonectria (F. buxicola SC), Geejayessia (F. staphyleae SC), Neocosmospora (F. solani SC) or Rectifusarium (F. ventricosum SC). The present study represents the first step to generating a new online monograph of Fusarium and allied fusarioid genera (www.fusarium.org).
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3. |
- Mattsson, Eskil, 1981, et al.
(author)
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Quantification of carbon stock and tree diversity of homegardens in a dry zone area of Moneragala District, Sri Lanka
- 2015
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In: Agroforestry Systems. - : Springer Science and Business Media LLC. - 1572-9680 .- 0167-4366. ; 89:3, s. 435-445
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Journal article (peer-reviewed)abstract
- Homegarden agroforestry systems are suggested to hold a large potential for climate change mitigation and adaptation. This is due to their multifunctional role in providing income, food and ecosystem services while decreasing pressure on natural forests and hence saving and storing carbon. In this paper, above-ground biomass carbon and tree species diversity of trees was quantified in homegardens around two villages in the dry south-eastern part of Moneragala district of Sri Lanka. A total of 45 dry zone homegardens were sampled on size, diameter at breast height, tree height and species diversity. Using allometric equations, we find a mean above-ground biomass stock of 13 mega grams of carbon per hectare (Mg C ha−1) with a large range among homegardens (1–56 Mg C ha−1, n = 45) due to a variation of tree diversity and composition between individual homegardens. Mean above-ground carbon stock per unit area was higher in small homegardens (0.2 ha, 26 Mg C ha−1, n = 11) and statistically different compared to medium (0.4–0.8 ha, 9 Mg C ha−1, n = 27) and large (1.0–1.2 ha, 8 Mg C ha−1, n = 7) homegardens. In total, 4,278 trees were sampled and 70 tree species identified and recorded. The Shannon Wiener index were used to evaluate diversity per homegarden and ranged from 0.76 to 3.01 with a mean value of 2.05 ± 0.07 indicating a medium evenly distributed diversity of sampled tree species. The results show a vast heterogeneity in terms of carbon stock and tree diversity within the less studied dry zone homegardens; results that contribute to more knowledge of their expansion potential as well as climate mitigation and adaptation potential. The results are also useful for whether homegardens should be considered to be included as an activity to enhance natural forest cover within Sri Lanka’s newly commenced UN-REDD National Programme.
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4. |
- Ritter, Camila, et al.
(author)
-
Biodiversity assessments in the 21st century: The potential of insect traps to complement environmental samples for estimating eukaryotic and prokaryotic diversity using high-throughput DNA metabarcoding.
- 2019
-
In: Genome. - : Canadian Science Publishing. - 1480-3321 .- 0831-2796. ; 62:3, s. 147-159
-
Journal article (peer-reviewed)abstract
- The rapid loss of biodiversity, coupled with difficulties in species identification, call for innovative approaches to assess biodiversity. Insects make up a substantial proportion of extant diversity and play fundamental roles in any given ecosystem. To complement morphological species identification, new techniques such as metabarcoding make it possible to quantify insect diversity and insect-ecosystem interactions through DNA sequencing. Here we examine the potential of bulk insect samples (i.e., containing many non-sorted specimens) to assess prokaryote and eukaryote biodiversity and to complement the taxonomic coverage of soil samples. We sampled 25 sites on three continents and in various ecosystems, collecting insects with Slam-traps (Brazil) and Malaise-traps (South Africa and Sweden). We then compared our diversity estimates with the results obtained with biodiversity data from soil samples from the same localities. We found a largely different taxonomic composition between the soil and insect samples, testifying to the potential of bulk insect samples to complement soil samples. Finally, we found that non-destructive DNA extraction protocols, which preserve insect specimens for morphological studies, constitute a promising choice for cost-effective biodiversity assessments. We propose that the sampling and sequencing of insect samples should become a standard complement for biodiversity studies based on environmental DNA.
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5. |
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6. |
- Messing, Ingmar, et al.
(author)
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Rovdrift på åkermark i Uppsala
- 2012
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In: Upsala nya tidning. - 1104-0173. ; , s. 5-
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Other publication (pop. science, debate, etc.)
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7. |
- Liljenström, Hans, et al.
(author)
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Scoping Report on Socio-Economic and Land Use Dynamics in the Stockholm-Mälar Region
- 2014
-
Reports (other academic/artistic)abstract
- This scoping report for the COMPLEX work package 4 (WP4) on Socio-Economic and Land Use Dynamics in the Stockholm-Mälar Region has several objectives. The first is to present and outline the state-of-the-art, including a literature review, with regard to complex pathways to a low carbon society, with special relevance to the Stockholm-Mälar region. It will do so in a larger context of complex socio-natural systems, with an emphasis on a green economy, bioen-ergy and land use, as well as on societal transformation and behavioural change. Another objec-tive is to inform primarily our partners in COMPLEX, but also others who might be interested, including stakeholders in our study region. Perhaps the most important objective with this re-port is to provide a basis for the collaborative work within our work package, and with our col-leagues elsewhere. In this second revised version of the report, we have extended some parts, and shortened others, depending on suggestions and interesting new information. A part of this new information has come from a stakeholder workshop held in Sigtuna in early 2014, which to a great extent could contribute to a more elaborate analysis of stakeholder and policy maker positions. In addition, there is now a more extensive description of relevant land use modelling. The illustrations included in this report are extracted from scientific articles and other material that we are referring to. Their origin is explicitly cited but no copyright authorization has been requested, while this report is intended primarily for internal spread and use within the COM-PLEX consortium and its networks.
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8. |
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9. |
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10. |
- Weslien, Per, 1963, et al.
(author)
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Carrot cropping on organic soil is a hotspot for nitrous oxide emissions
- 2012
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In: Nutrient Cycling in Agroecosystems. - : Springer Science and Business Media LLC. - 1385-1314 .- 1573-0867. ; 94:2-3, s. 249-253
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Journal article (peer-reviewed)abstract
- The emissions of the greenhouse gas nitrous oxide (N2O) were measured from a non nitrogen fertilized carrot (Daucus carota ssp. sativa) field on an organic soil in Sweden during one cropping and post-harvest season. The cumulative emission during the measuring period of 149 days was 41 (±2.8) kg N2O ha−1. Dividing the measuring period into a cropping and a post-harvest period revealed that the presence of carrots strongly stimulated N2O emissions, as the emission during the cropping period was one order of magnitude higher compared to the post-harvest period. The N2O emission from the carrot field were higher than fluxes reported from cereal crop and grass production, but in the same order as reported fluxes from vegetable cropping on organic soils. In conclusion, our results indicate that the cultivation of root vegetable, such as carrots, on organic soil can be a high point source for N2O emissions.
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11. |
- Montelius, Malin
(author)
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Chlorine Cycling in Terrestrial Environments
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Chlorinated organic compounds (Clorg) are produced naturally in soil. Formation and degradation of Clorg affect the chlorine (Cl) cycling in terrestrial environments and chlorine can be retained or released from soil. Cl is known to have the same behaviour as radioactive chlorine-36 (36Cl), a long-lived radioisotope with a half-life of 300,000 years. 36Cl attracts interest because of its presence in radioactive waste, making 36Cl a potential risk for humans and animals due to possible biological uptake. This thesis studies the distribution and cycling of chloride (Cl–) and Clorg in terrestrial environments by using laboratory controlled soil incubation studies and a forest field study. The results show higher amounts of Cl– and Clorg and higher chlorination rates in coniferous forest soils than in pasture and agricultural soils. Tree species is the most important factor regulating Cl– and Clorg levels, whereas geographical location, atmospheric deposition, and soil type are less important. The root zone was the most active site of the chlorination process. Moreover, this thesis confirms that bulk Clorg dechlorination rates are similar to, or higher than, chlorination rates and that there are at least two major Clorg pools, one being dechlorinated quickly and one remarkably slower. While chlorination rates were negatively influenced by nitrogen additions, dechlorination rates, seem unaffected by nitrogen. The results implicate that Cl cycling is highly active in soils and Cl– and Clorg levels result from a dynamic equilibrium between chlorination and dechlorination. Influence of tree species and the rapid and slow cycling of some Cl pools, are critical to consider in studies of Cl in terrestrial environments. This information can be used to better understand Cl in risk-assessment modelling including inorganic and organic 36Cl.
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12. |
- Svensson, Teresia, 1975-, et al.
(author)
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Chlorination of soil organic matter : The role of humus type and land use
- 2022
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In: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 806p2
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Journal article (peer-reviewed)abstract
- The levels of natural organic chlorine (Clorg) typically exceed levels of chloride in most soils and is therefore clearly of high importance for continental chlorine cycling. The high spatial variability raises questions on soil organic matter (SOM) chlorination rates among topsoils with different types of organic matter. We measured Clorg formation rates along depth profiles in six French temperate soils with similar Cl deposition using 36Cl tracer experiments. Three forest sites with different humus types and soils from grassland and arable land were studied. The highest specific chlorination rates (fraction of chlorine pool transformed to Clorg per time unit) among the forest soils were found in the humus layers. Comparing the forest sites, specific chlorination was highest in mull-type humus, characterized by high microbial activity and fast degradation of the organic matter. Considering non-humus soil layers, grassland and forest soils had similar specific chlorination rates in the uppermost layer (0–10 cm below humus layer). Below this depth the specific chlorination rate decreased slightly in forests, and drastically in the grassland soil. The agricultural soil exhibited the lowest specific chlorination rates, similar along the depth profile. Across all sites, specific chlorination rates were correlated with soil moisture and in combination with the patterns on organic matter types, the results suggest an extensive Cl cycling where humus types and soil moisture provided best conditions for microbial activity. Clorg accumulation and theoretical residence times were not clearly linked to chlorination rates. This indicates intensive Cl cycling between organic and inorganic forms in forest humus layers, regulated by humic matter reactivity and soil moisture, while long-term Clorg accumulation seems more linked with overall deep soil organic carbon stabilization. Thus, humus types and factors affecting soil carbon storage, including vegetation land use, could be used as indicators of potential Clorg formation and accumulation in soils.
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13. |
- Ernfors, Maria
(author)
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Challenges of accounting nitrous oxide emissions from agricultural crop residues
- 2023
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In: Global Change Biology. - 1354-1013 .- 1365-2486. ; 29, s. 6846-6855
-
Journal article (peer-reviewed)abstract
- Crop residues are important inputs of carbon (C) and nitrogen (N) to soils and thus directly and indirectly affect nitrous oxide (N2O) emissions. As the current inventory methodology considers N inputs by crop residues as the sole determining factor for N2O emissions, it fails to consider other underlying factors and processes. There is compelling evidence that emissions vary greatly between residues with different biochemical and physical characteristics, with the concentrations of mineralizable N and decomposable C in the residue biomass both enhancing the soil N2O production potential. High concentrations of these components are associated with immature residues (e.g., cover crops, grass, legumes, and vegetables) as opposed to mature residues (e.g., straw). A more accurate estimation of the short-term (months) effects of the crop residues on N2O could involve distinguishing mature and immature crop residues with distinctly different emission factors. The medium-term (years) and long-term (decades) effects relate to the effects of residue management on soil N fertility and soil physical and chemical properties, considering that these are affected by local climatic and soil conditions as well as land use and management. More targeted mitigation efforts for N2O emissions, after addition of crop residues to the soil, are urgently needed and require an improved methodology for emission accounting. This work needs to be underpinned by research to (1) develop and validate N2O emission factors for mature and immature crop residues, (2) assess emissions from belowground residues of terminated crops, (3) improve activity data on management of different residue types, in particular immature residues, and (4) evaluate long-term effects of residue addition on N2O emissions.
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14. |
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15. |
- Nadeau, Elisabet, et al.
(author)
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Effects of sulphur fertilization in organically cultivated faba bean
- 2020
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In: Agricultural and Food Science. - : Agricultural and Food Science. - 1459-6067 .- 1795-1895. ; 29, s. 471–481-
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Journal article (peer-reviewed)abstract
- Optimal seed yield and quality requires that the sulphur (S) demand of faba bean (Vicia faba L.) is ensured. The ef-fect of S fertilization on organic cultivated faba bean was investigated under field conditions during two growing seasons (2017–2018), in Sweden. Kieserite (MgSO4) and gypsum (CaSO4) were applied at a rate of 20 and 40 kg ha-1to study the effect on faba bean growth, yield, crude protein (CP) content and amino acid (AA) composition. Gyp-sum and kieserite significantly increased S concentration of faba bean dry matter (DM) in 2017. The S concentra-tion ranged from 0.20% to 0.23% of DM compared to 0.18% in the untreated control. In 2018, kieserite application at 40 kg ha-1 significantly increased S concentration to 0.15% compared to 0.12% in the untreated control. The faba bean plants did, however, not respond neither with increased growth nor increased seed yield. The seed quality in terms of CP and S-containing AA, was not affected by S fertilization, however, significant differences were observed between the experimental sites.
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16. |
- Nilsson, R. Henrik, 1976, et al.
(author)
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Improving ITS sequence data for identification of plant pathogenic fungi
- 2014
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In: Fungal Diversity. - : Springer Science and Business Media LLC. - 1560-2745 .- 1878-9129. ; 67:1, s. 11-19
-
Journal article (peer-reviewed)abstract
- Plant pathogenic fungi are a large and diverse assemblage of eukaryotes with substantial impacts on natural ecosystems and human endeavours. These taxa often have complex and poorly understood life cycles, lack observable, discriminatory morphological characters, and may not be amenable to in vitro culturing. As a result, species identification is frequently difficult. Molecular (DNA sequence) data have emerged as crucial information for the taxonomic identification of plant pathogenic fungi, with the nuclear ribosomal internal transcribed spacer (ITS) region being the most popular marker. However, international nucleotide sequence databases are accumulating numerous sequences of compromised or low-resolution taxonomic annotations and substandard technical quality, making their use in the molecular identification of plant pathogenic fungi problematic. Here we report on a concerted effort to identify high-quality reference sequences for various plant pathogenic fungi and to re-annotate incorrectly or insufficiently annotated public ITS sequences from these fungal lineages. A third objective was to enrich the sequences with geographical and ecological metadata. The results – a total of 31,954 changes – are incorporated in and made available through the UNITE database for molecular identification of fungi (http://unite.ut.ee), including standalone FASTA files of sequence data for local BLAST searches, use in the next-generation sequencing analysis platforms QIIME and mothur, and related applications. The present initiative is just a beginning to cover the wide spectrum of plant pathogenic fungi, and we invite all researchers with pertinent expertise to join the annotation effort.
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17. |
- Nilsson, R. Henrik, 1976
(author)
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Unifying fungi
- 2015
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In: Science & Technology. - 2049-2391 .- 2049-2405. ; :14, s. 204-206
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Journal article (other academic/artistic)
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18. |
- Nyberg, Anna, et al.
(author)
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Potential methods for estimating nitrogen fertilizer value of organic residues
- 2012
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In: Soil Use and Management. - : Wiley. - 0266-0032 .- 1475-2743. ; 28, s. 283-291
-
Journal article (peer-reviewed)abstract
- New organic fertilizers based on waste products are continually being introduced in agriculture. Their nitrogen (N) fertilizer value of their total N and mineral N content varies widely, creating a demand for standardized laboratory methods. This study evaluated some potential methods for estimating the N fertilizer value of different kinds of organic fertilizers. The methods were evaluated against the N fertilizer value obtained from a ryegrass pot experiment. Fifteen fertilizers were tested, including different kinds of manure, powders from meat, bone, blood and feathers, rapeseed cake, lucerne pellets, sewage sludge, biogas residue, vinasse and mussel compost. Mineral fertilizer equivalents (MFE) were calculated as the fraction of total N (MFE) or organic N (MFEorg) out of total N that has the same availability to plants as inorganic N. Mineral N content (% of total N added with organic residue) after 4 weeks of incubation of soil was correlated to MFE (r2 = 0.78), but was on average 17% lower. Warm water-extractable N, amino acid N and crude fibre analysis all proved to be unsatisfactory as methods for estimating MFE or MFEorg. However, the carbon/nitrogen ratio accurately reflected short-term plant-available N through a negative linear relationship (r2 = 0.83) and would thus be a very useful method for estimating MFE, with MFE decreasing by 5% per unit increase in C/N ratio. The results also indicated that the analysis of near infrared reflectance (NIR) spectra can be an even quicker and cheaper method to estimate MFE of organic residues, but this issue requires further research.
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19. |
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20. |
- Råberg, Tora, et al.
(author)
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Productivity in an arable and stockless organic cropping system may be enhanced by strategic recycling of biomass
- 2019
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In: Renewable Agriculture and Food Systems. - : Cambridge University Press. - 1742-1705 .- 1742-1713. ; 34:1, s. 20-32
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Journal article (peer-reviewed)abstract
- Recirculation of nitrogen (N) from crop residue and green-manure biomass resources may reduce the need to add new reactive N to maintain crop yield and quality. The aim of this study was to determine how different strategies for recycling residual and green-manure biomass influence yield and N concentration of the edible parts of food crops in a stockless organic cropping system. For this purpose, three biomass distribution treatments were investigated in a field experiment, based on a cropping system designed to produce both high-quality food crops and biomass resources from crop residues, cover crops and a green-manure ley. The three treatments, applied at the cropping system level, were: (1) incorporating the aboveground biomass resources in situ (IS); (2) harvesting, ensiling and redistributing the same biomass resources to the non-legume crops (biomass redistribution, BR); and (3) harvesting, ensiling and using the biomass resources as substrate for production of bio-methane via anaerobic digestion (AD) followed by distribution of the digestate as bio-fertilizer to the non-legume crops. The redistribution of ensiled (BR) and digested (AD) biomass did not increase the yield of the edible parts in winter rye (Secale cereal L.), white cabbage (Brassica oleracea L.) or red beet (Beta vulgaris L.) compared with leaving the biomass on the ground at harvest (IS). The BR treatment increased the yield of lentil intercropped with oat, compared with IS treatment in one of the two studied years. The total biomass yield of the cover crop following winter rye was significantly higher in the BR treatment than in IS in both years. The legume proportion in the green-manure ley was significantly higher in the AD and BR treatments as compared with IS in one of the experimental years. This study showed that strategic biomass redistribution has the potential to enhance biomass productivity while maintaining food crop yields, thereby enhancing whole system productivity. Biomass redistribution systems both with and without biogas digestion offer a new strategy for the development of multifunctional arable cropping systems that rely on internal nutrient cycling.
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21. |
- Schwelm, Arne, et al.
(author)
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New kid on the block - the clubroot pathogen genome moves the plasmodiophorids into the genomic era
- 2016
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In: European Journal of Plant Pathology. - : Springer Science and Business Media LLC. - 0929-1873 .- 1573-8469. ; 145, s. 531-542
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Journal article (peer-reviewed)abstract
- Plasmodiophora brassicae causes clubroot on cruciferous plants and causes worldwide huge economical losses on important Brassica crops. P. brassicae infection produces large root galls, the clubroots, which can also affect the upper plant parts by reduced water and nutrient uptake and redirection of assimilates from leaves to roots. P. brassicae is an obligate biotrophic protist in the plasmodiophorids within the eukaryote supergroup of Rhizaria and is unrelated to other known plant pathogens. Plasmodiophorids can be parasites of plants and oomycetes. The recently released genome of P. brassicae is only the third in the poorly studied Rhizaria and the first plant pathogenic genome of this eukaryotic group. The P. brassicae genome was estimated to be 25.5 Mb in size and predicted to contain 9730 gene models. A transcriptome of P. brassicae and Spongospora subterranea, the potato scab pathogen was also presented. Consequently, for the first time large scale data for a eukaryotic plant pathogen group outside the fungi and oomycetes are now available. This review highlights selected characteristics of the P. brassicae genome including molecular events shown or predicted to take place in each phase of its life-cycle, such as manipulation of: 1) host primary metabolism, 2) plant hormone homeostasis, and 3) plant defense. Further, future directions and challenges in the P. brassicae and plasmodiophorid genomic research are discussed.
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22. |
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23. |
- Abarenkov, Kessy, et al.
(author)
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Protax-fungi: A web-based tool for probabilistic taxonomic placement of fungal internal transcribed spacer sequences
- 2018
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In: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 220:2, s. 517-525
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Journal article (peer-reviewed)abstract
- © 2018 New Phytologist Trust. Incompleteness of reference sequence databases and unresolved taxonomic relationships complicates taxonomic placement of fungal sequences. We developed Protax-fungi, a general tool for taxonomic placement of fungal internal transcribed spacer (ITS) sequences, and implemented it into the PlutoF platform of the UNITE database for molecular identification of fungi. With empirical data on root- and wood-associated fungi, Protax-fungi reliably identified (with at least 90% identification probability) the majority of sequences to the order level but only around one-fifth of them to the species level, reflecting the current limited coverage of the databases. Protax-fungi outperformed the Sintax and Rdb classifiers in terms of increased accuracy and decreased calibration error when applied to data on mock communities representing species groups with poor sequence database coverage. We applied Protax-fungi to examine the internal consistencies of the Index Fungorum and UNITE databases. This revealed inconsistencies in the taxonomy database as well as mislabelling and sequence quality problems in the reference database. The according improvements were implemented in both databases. Protax-fungi provides a robust tool for performing statistically reliable identifications of fungi in spite of the incompleteness of extant reference sequence databases and unresolved taxonomic relationships.
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24. |
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25. |
- Ali, Liaqat
(author)
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Pre-harvest factors affecting quality and shelf-life in raspberries and blackberries (Rubus spp. L.)
- 2012
-
Doctoral thesis (other academic/artistic)abstract
- Fruit including berries have been demonstrated to exhibit a broad spectrum of benefits including protection against cardiovascular, neurological, and lung diseases, as well as having antioxidant, antimicrobial, anti-inflammatory, anti- diabetic and anti-aging properties. These protective effects are reported to be due to their high content of bioactive compounds, such as vitamin C, vitamin E, phenolic acids, ellagitannins, flavonoids and carotenoids. This thesis investigated the effect of pre- and postharvest factors on the concentrations of bioactive compounds in raspberries and blackberries. The factors studied included genetic variability, organic and synthetic fertilizers, seasonal variation (harvest-to-harvest and annual variation) in greenhouse, high tunnel and open field production, and post-harvest storage. Concentrations of bioactive compounds (anthocyanins, vitamin C, ellagic acid, carotenoids) in the berries, or in the leaves, were quantitatively analysed by high-performance liquid chromatography, and total phenolics were analysed by a spectrophotometric method. Generative parameters (yield, fruit size) investigated for the cultivar difference and organic nitrogen, responded differently to the nitrogen level within cultivars and varied significantly in primocane raspberries. Taste compounds, such as total acidity and different sugars, varied during the season and with nutrient regimes. Time of harvest also affected the ellagic acid content, which was high in early season, and the vitamin C content, which was high in late season in primocane raspberries. Significant changes were also found between different years. Vitamin C decreased significantly with high synthetic N and with low K application, but the application of high N with high K showed positive influence in the level of nutrients and bioactive compounds in blackberries except for ellagic acid. Increased level of organic fertilization (12-17 g N/plant) in primocane raspberries caused only minor changes in the analysed compounds. The post-harvest performance of raspberries regarding the levels of bioactive compounds was less dynamic than in blackberries. In addition, raspberries harvested in late season showed comparatively less changes in sugar content during storage as compared to early harvest, indicating less enzymatic activity in the late season.
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26. |
- Bengtsson, Stefan, et al.
(author)
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Uptake and Retention of Simulated Fallout of Radiocaesium and Radiostrontium by Different Agriculture Crops
- 2015
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In: Radionuclides in the Environment. - Cham : Springer International Publishing. - 9783319221700 ; , s. 115-132
-
Book chapter (other academic/artistic)abstract
- Abstract: The contamination level in potato, oilseed rape and wheat in terms of tubers, seeds and foliage has been investigated after the foliar application of wet-deposited 134Cs and 85Sr at different growth stages in a microscale field experiment conducted over consecutive years. The results indicate that the application of radionuclides in the beginning of the growth season resulted in low 134Cs and 85Sr activity in both seeds of wheat, oilseed rape and potato tubers across sampling occasions. In the middle of the growth season during radionuclide fallout, 134Cs activity in potato tubers across sampling occasions was highest. The spraying of radionuclides at later stages resulted in even lower 134Cs activity in potato tubers but increased activity in seeds of wheat and oilseed rape.
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27. |
- Erhagen, Björn, et al.
(author)
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Temperature sensitivity of heterotrophic soil CO2 production increases with increasing carbon substrate uptake rate
- 2015
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In: Soil Biology and Biochemistry. - : Elsevier BV. - 0038-0717 .- 1879-3428. ; 80, s. 45-52
-
Journal article (peer-reviewed)abstract
- Temperature profoundly affects saprotrophic respiration rates, and carbon quality theory predicts that the rates' temperature Sensitivity should increase as the quality of the carbon source declines. However, reported relationships between saprotrophic respiration responses to temperature and carbon quality vary widely. Some of this variability may arise from confounding effects related to both substrate quality and substrate availability. The importance of these variables, as well as substrate diffusion and uptake rates, for the temperature sensitivity of saprotrophic respiration has been validated theoretically, but not empirically demonstrated. Thus, we tested effects of varying substrate uptake rates on the temperature sensitivity of organic carbon degradation. For this purpose we created a model system using the organic layer (O-horizon), of a boreal forest soil, specifically to test effects of varying monomer uptake and release rates. The addition of both monomers and polymers generally increased the temperature sensitivity of saprotrophic respiration. In response to added monomers, there was a linear increase in the temperature sensitivity of both substrate-induced respiration and the specific growth rate with increasing rate of substrate uptake as indicated by the CO2 production at 14 degrees C. Both of these responses diverge from those predicted by the carbon quality theory, but they provide the first empirical evidence consistent with model predictions demonstrating increased temperature sensitivity with increased uptake rate of carbon monomers over the cell membrane. These results may explain why organic material of higher carbon quality induces higher temperature responses than lower carbon quality compounds, without contradicting carbon quality theory.
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28. |
- Fransson, Petra, et al.
(author)
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Mycorrhizal associations and soil properties of native Allanblackia stuhlmannii stands in the Eastern Usambara Mountains, Tanzania
- 2016
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In: Annals of Applied Biology. - : Wiley. - 0003-4746. ; 169, s. 369-383
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Journal article (peer-reviewed)abstract
- Allanblackia stuhlmannii is a tree species currently under domestication. Potential mycorrhizal relationships of A. stuhlmannii and soil properties of native stands were investigated to determine the soil-environmental requirements of the species. Roots and soil samples were collected from five sites with A. stuhlmannii stands along an altitudinal transect in Amani Nature Reserve, Tanzania. Mycorrhizal status was investigated by combining microscopy with molecular analysis of the fungal communities. Soil adjacent to the A. stuhlmannii seedlings was analysed for physical and chemical properties and the sites were characterised. We showed that A. stuhlmannii form symbiosis with arbuscular mycorrhizal fungi, and that there was a diverse microbiome associated with the roots. The soils, classified as Ferralsol and Acrisol, were very well drained, had a pH(CaCl2) generally at or below 4, high exchangeable acidity and content of sesquioxides and low effective cation exchange capacity and concentrations of most nutrients. We conclude that A. stuhlmannii is tolerant to high Al availability and possesses mechanisms for acquisition of P and other macronutrients at low soil availability, possibly through mycorrhizal symbiosis. However, being adapted to low-pH soils, it may be less efficient in acquiring Fe, Mn and/or Zn at higher soil pH. Thus, it may be most suited to introduction on farms situated on acid soils.
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29. |
- Jacobsson, Karin, et al.
(author)
-
Bacteria considered as biocontrol agents to control growth of white clover on golf courses
- 2010
-
In: Acta Agriculturae Scandinavica, Section B - Soil and Plant Science. - : Informa UK Limited. - 0906-4710 .- 1651-1913. ; 60, s. 193-198
-
Journal article (peer-reviewed)abstract
- In recreational areas, such as parks and golf courses, plants like white clover are considered as weeds. In an attempt to identify biocontrol agents that can be used to control growth of clover, a number of bacterial isolates were studied. Two approaches were considered: soil treatment for suppression of Rhizobium leguminosarum, a symbiotic bacteria providing clover with nitrogen, and direct suppression by leaf-spray treatment. Selected bacterial isolates were first screened against R. leguminosarum in a dual culture. Some of the tested isolates significantly inhibited the growth of R. leguminosarum. Soil inoculation of these isolates had a significant growth-reducing effect on clover seedlings. Leaf-spray treatment of bacteria had a significant impact on clover growth. Depending on the plant growth stage, this effect can reach up to 86% reduction in clover shoot dry weight. Different temperatures did not influence the effect on clover. The growth-reducing effect of bacteria was also shown on another important dicotyledonous weed, Chenopodium album.
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30. |
- Jayasiri, Subashini C., et al.
(author)
-
The Faces of Fungi database: fungal names linked with morphology, phylogeny and human impacts
- 2015
-
In: Fungal diversity. - : Springer Science and Business Media LLC. - 1560-2745 .- 1878-9129. ; 74:1, s. 3-18
-
Journal article (peer-reviewed)abstract
- Taxonomic names are key links between various databases that store information on different organisms. Several global fungal nomenclural and taxonomic databases (notably Index Fungorum, Species Fungorum and MycoBank) can be sourced to find taxonomic details about fungi, while DNA sequence data can be sourced from NCBI, EBI and UNITE databases. Although the sequence data may be linked to a name, the quality of the metadata is variable and generally there is no corresponding link to images, descriptions or herbarium material. There is generally no way to establish the accuracy of the names in these genomic databases, other than whether the submission is from a reputable source. To tackle this problem, a new database (FacesofFungi), accessible at www.facesoffungi.org (FoF) has been established. This fungal database allows deposition of taxonomic data, phenotypic details and other useful data, which will enhance our current taxonomic understanding and ultimately enable mycologists to gain better and updated insights into the current fungal classification system. In addition, the database will also allow access to comprehensive metadata including descriptions of voucher and type specimens. This database is user-friendly, providing links and easy access between taxonomic ranks, with the classification system based primarily on molecular data (from the literature and via updated web-based phylogenetic trees), and to a lesser extent on morphological data when molecular data are unavailable. In FoF species are not only linked to the closest phylogenetic representatives, but also relevant data is provided, wherever available, on various applied aspects, such as ecological, industrial, quarantine and chemical uses. The data include the three main fungal groups (Ascomycota, Basidiomycota, Basal fungi) and fungus-like organisms. The FoF webpage is an output funded by the Mushroom Research Foundation which is an NGO with seven directors with mycological expertise. The webpage has 76 curators, and with the help of these specialists, FoF will provide an updated natural classification of the fungi, with illustrated accounts of species linked to molecular data. The present paper introduces the FoF database to the scientific community and briefly reviews some of the problems associated with classification and identification of the main fungal groups. The structure and use of the database is then explained. We would like to invite all mycologists to contribute to these web pages.
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31. |
- Klemedtsson, Åsa Kasimir, 1956
(author)
-
Lustgasavgång från jordbruksmark
- 2009
-
Reports (other academic/artistic)abstract
- Regeringen fattade den 26 juni 2008 beslut om ändring av Jordbruksverkets regleringsbrev rörande uppdraget ”Åtgärdsprogram för minskade växtnäringsförluster” vilket ersätts av uppdraget; ”Jordbruksverket ska efter samråd med berörda myndigheter och organisationer lämna förslag till ett handlingsprogram för minskade växtnärings- och växthusgasförluster från jordbruket för perioden 2011 till och med 2016 med utblick till 2020.” Framtagandet av ett handlingsprogram inom jordbruksverket bedrivs som ett projekt vilket ska utgöra underlag för vidare beslut och genomförande. Föreslagna åtgärder och styrmedel ska vara realistiska, genomförbara och kostnadseffektiva. Förslag till nytt handlingsprogram ska vara färdigt våren 2010. Som ett led i projektet gavs ett uppdrag till Åsa Kasimir Klemedtsson att utreda och ge förslag till möjliga åtgärder i jordbruket som kan minska lustgasavgången från jordbruksmark. Rapporteringen följer de anvisningar som gavs.
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32. |
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33. |
- Kätterer, Thomas
(author)
-
Soil Carbon Sequestration – for climate, food security and ecosystem services
- 2015
-
In: ANP.
-
Other publication (pop. science, debate, etc.)abstract
- Soil carbon sequestration and preservation of present stocks reduces net global greenhouse gas emission and can contribute significantly to both Nordic and international goals of limiting serious climate change. In order to achieve this, sustainable use of soil resources, better soil and water management practices, and restoration of degraded soils is needed. Protection and restoration of soil organic carbon are also key solutions to many of the most pressing global challenges facing mankind today. Highlighting the importance of the soil and the multiple benefits of soil organic carbon sequestration has never been more needed than now.
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34. |
- Linner, Harry, et al.
(author)
-
Agricultural land needs protection
- 2012
-
In: Acta Agriculturae Scandinavica, Section B - Soil and Plant Science. - : Informa UK Limited. - 0906-4710 .- 1651-1913. ; 62, s. 706-710
-
Journal article (peer-reviewed)
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35. |
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36. |
- Nadeau, Elisabet, et al.
(author)
-
Protein quality of grass silage as affected by silage additives and its effects on dairy cow performance
- 2015
-
In: Journal of Animal Science. - 0021-8812 .- 1525-3163. ; 93, s. 206-
-
Conference paper (peer-reviewed)abstract
- This experiment was conducted to evaluate the effects of improved protein quality of grass silage by additive use on dairy cow intake and performance. Grass from the first regrowth was wilted to 33% DM before being precision chopped and treated with the inoculant Kofasil Duo (Lactobacillus plantarum/Lactobacillus buchneri, 200,000 cfu/g) or with the chemical additive Kofasil Ultra K (sodium nitrite, hexamine, potassium sorbate, sodium benzoate and sodium propionate, 2 L/T, Addcon Europe GmbH), which were compared with a control without additive. The forage was ensiled in hard-pressed round bales before being fed to 48 dairy cows (150 DIM) in a continuous trial for 9 wk using 8 cows per treatment. Cows were blocked according to breed, parity, DIM and milk yield. The silage contained 15% CP, 47% NDF, 3.3% WSC, 8.2% lactic acid, 2.1% acetic acid and 0.25% NH3-N of DM with minor differences between treatments. Rumen undegradable protein (RUP) of the silage at 5% passage rate was 22, 23 and 24% of CP for control (C), inoculant (I) and salt-based (S) additive, respectively. Diets were isonitrogenous (15.1% of DM) and isoenergetic (11.4 MJ/kg DM) varying in RUP (4.7% (high) and 2.5% (low) of DM). Concentrate UDP was 2.9 and 8.6% of DM. Dietary forage proportion of the TMR was 58% of DM. Data were analyzed using PROC MIXED of SAS with RUP, silage and week as fixed factors and block as a random factor. High RUP diet had higher milk yield than low RUP diet (29.4 vs. 27.9 kg; P < 0.05). The DM intake was not affected by RUP and silage treatment. Yields of milk and ECM were higher for the I and S diets than for the C diet at low RUP (28.9 vs. 26.0 kg milk, P < 0.01; 30.6 vs. 27.1 kg ECM, P < 0.001) whereas there was no effect of additive treatment in the high RUP diet. Milk fat and protein did not differ between silage treatments. Feed efficiency was higher for the I and S diets than for the C diet at the low RUP (1.6 vs. 1.3 kg of ECM/kg DM intake, P < 0.001) but not at the high RUP. The increased milk yield and feed efficiency when fed a diet with low RUP can partly be explained by increased RUP of the I and S silages.
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37. |
- Nilsson, R. Henrik, 1976, et al.
(author)
-
Top 50 most wanted fungi
- 2016
-
In: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 12, s. 29-40
-
Journal article (peer-reviewed)abstract
- Environmental sequencing regularly recovers fungi that cannot be classified to any meaningful taxonomic level beyond “Fungi”. There are several examples where evidence of such lineages has been sitting in public sequence databases for up to ten years before receiving scientific attention and formal recognition. In order to highlight these unidentified lineages for taxonomic scrutiny, a search function is presented that produces updated lists of approximately genus-level clusters of fungal ITS sequences that remain unidentified at the phylum, class, and order levels, respectively. The search function (https://unite.ut.ee/top50.php) is implemented in the UNITE database for molecular identification of fungi, such that the underlying sequences and fungal lineages are open to third-party annotation. We invite researchers to examine these enigmatic fungal lineages in the hope that their taxonomic resolution will not have to wait another ten years or more.
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38. |
- Oyewole, Olusegun Ayodeji
(author)
-
Soil nitrogen fluxes and root uptake in the boreal forest : key processes to plant nitrogen nutrition
- 2015
-
Doctoral thesis (other academic/artistic)abstract
- Nitrogen (N) is essential for growth and net primary production of plants. However, N acquisition by plants is influenced by movement of soil N compounds from bulk soil to plant roots and uptake of N by roots. This thesis is aimed at deepening our knowledge on these key processes involved in plant N acquisition in the N-limited boreal forest. To address this aim, a novel, non-invasive microdialysis technique was employed. Amino acids dominated N fluxes in the boreal forest soils. Further, plant roots were shown to have the capacity to absorb organic and inorganic N present in the measured soil fluxes, but these soil fluxes, rather than root uptake, may limit plant N acquisition. The microdialysis technique was further developed to enable simultaneous estimation of diffusion and mass flow of N in soil. Applying this refinement of the technique in the field showed that mass flow significantly increased flux rates of soil N in the boreal forest ecosystem, and that it also altered the chemical composition of the N fluxes. The results from the studies presented in this thesis highlight the potential of the microdialysis technique to improve our understanding of the intrinsic processes involved in N acquisition by plant roots. They also suggest that amino acids might comprise an important source of N for plants in the boreal forest ecosystem. The results suggest that mass flow plays an important role for plant N acquisition in the boreal forest, and mass flow might increase the share of nitrate, particularly in nutrient-rich ecosystems. This finding opens a discussion on the role of transpiration in plant N nutrition, with implications for our understanding of how plant N nutrition will be affected by, among other things, elevated CO2, increased temperatures, and N fertilization.
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39. |
- Simonsson, Magnus, et al.
(author)
-
Estimating weathering rates using base cation budgets in a Norway spruce stand on podzolised soil: Analysis of fluxes and uncertainties
- 2015
-
In: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 340, s. 135-152
-
Journal article (peer-reviewed)abstract
- Since forestry is often allocated to soils with a low weathering capacity, reliable estimates of weathering rates are crucial in analyses of sustainability, e.g. of whole-tree and stump harvesting. In the present study, weathering rates (kg ha(-1) yr(-1)) for base cations were estimated using cation budgets in a replicated (n = 4) experimental Norway spruce (Picea abies (L) Karst.) plantation situated on a nutrient-poor glacial till in south-west Sweden and aged 25-39 years during the study period. Weathering rates (central values) were 2.4, 1.4, 0.3 and 2.3 kg ha(-1) yr(-1) for Ca, Mg, K and Na, respectively. However, weathering was a minor flux in the overall cycling of these cations in the ecosystem, and the confidence intervals of the weathering estimates had amplitudes that generally were greater than the central values. The overall uncertainties were divided into (i) regular standard errors of the mean, expressing spatial variability, sampling errors and random method-related errors in data from measurements replicated over the experimental plots ('Type A' uncertainties), and (ii) estimated standard uncertainties accounting for systematic errors of methods, and of uncertainties in variables, functions and factors not replicated over the plots ('Type B' uncertainties). For Ca and K, bioaccumulation dominated the overall uncertainty. Most (>90 %) of this uncertainty, in turn, was of Type A (between-plot variability in measured stem diameters and cation concentrations); the remainder resulted from Type B uncertainties in allometric functions etc. Hence, regular standard errors over plots yielded a correct level of uncertainty of weathering estimates for these ions at the studied site. For Mg and Na, however, deposition and leaching were large terms in the cation budget. Whereas the uncertainty in deposition was mostly taken into account by plot-wise replicated measurements of throughfall (Type A uncertainty), Type B uncertainties were crucial to the estimates of leaching. Due to the fact that uncertainties accumulate when terms are added and subtracted in a cation budget, it is difficult to predict the sustainability of the pools of exchangeable cations from estimated weathering rates; it may be better to measure them directly in the soil. However, in the studied ecosystem these had a rapid turnover (mean residence time, 1-4 years), and underwent abrupt fluctuations over only a few years. A study performed during a limited time may therefore suffer from considerable temporal uncertainties, if the results are to be generalised for a longer period. (C) 2015 Elsevier B.V. All rights reserved.
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40. |
- Sundqvist, Maja K., et al.
(author)
-
Contrasting nitrogen and phosphorus dynamics across an elevational gradient for subarctic tundra heath and meadow vegetation
- 2014
-
In: Plant and Soil. - : Springer Netherlands. - 0032-079X .- 1573-5036. ; 383:1-2, s. 387-399
-
Journal article (peer-reviewed)abstract
- This study explores soil nutrient cycling processes and microbial properties for two contrasting vegetation types along an elevational gradient in subarctic tundra to improve our understanding of how temperature influences nutrient availability in an ecosystem predicted to be sensitive to global warming. We measured total amino acid (Amino-N), mineral nitrogen (N) and phosphorus (P) concentrations, in situ net N and P mineralization, net Amino-N consumption, and microbial biomass C, N and P in both heath and meadow soils across an elevational gradient near Abisko, Sweden. For the meadow, NH4 (+) concentrations and net N mineralization were highest at high elevations and microbial properties showed variable responses; these variables were largely unresponsive to elevation for the heath. Amino-N concentrations sometimes showed a tendency to increase with elevation and net Amino-N consumption was often unresponsive to elevation. Overall, PO4-P concentrations decreased with elevation and net P immobilization mostly occurred at lower elevations; these effects were strongest for the heath. Our results reveal that elevation-associated changes in temperature can have contrasting effects on the cycling of N and P in subarctic soils, and that the strength and direction of these effects depend strongly on dominant vegetation type.
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41. |
- Svensson, Teresia, 1975-, et al.
(author)
-
Chlorine cycling and the fate of Cl in terrestrial environments
- 2021
-
In: Environmental Science and Pollution Research. - : Springer. - 0944-1344 .- 1614-7499. ; 28:7, s. 7691-7709
-
Journal article (peer-reviewed)abstract
- Chlorine (Cl) in the terrestrial environment is of interest from multiple perspectives, including the use of chloride as a tracer forwater flow and contaminant transport, organochlorine pollutants, Cl cycling, radioactive waste (radioecology; 36Cl is of largeconcern) and plant science (Cl as essential element for living plants).During the past decades, there has been a rapid developmenttowards improved understanding of the terrestrial Cl cycle. There is a ubiquitous and extensive natural chlorination of organicmatter in terrestrial ecosystems where naturally formed chlorinated organic compounds (Clorg) in soil frequently exceed theabundance of chloride. Chloride dominates import and export from terrestrial ecosystems while soil Clorg and biomass Cl candominate the standing stock Cl. This has important implications for Cl transport, as chloride will enter the Cl pools resulting inprolonged residence times. Clearly, these pools must be considered separately in future monitoring programs addressing Clcycling. Moreover, there are indications that (1) large amounts of Cl can accumulate in biomass, in some cases representing themain Cl pool; (2) emissions of volatile organic chlorines could be a significant export pathway of Cl and (3) that there is aproduction of Clorg in tissues of, e.g. plants and animals and that Cl can accumulate as, e.g. chlorinated fatty acids in organisms.Yet, data focusing on ecosystem perspectives and combined spatiotemporal variability regarding various Cl pools are still scarce,and the processes and ecological roles of the extensive biological Cl cycling are still poorly understood.
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42. |
- Svensson, Teresia, 1975-
(author)
-
Measurements and fluxes of volatile chlorinated organic compounds (VOCl) from natural terrestrial sources : Measurement techniques and spatio-temporal variability of flux estimates
- 2019
-
Reports (other academic/artistic)abstract
- Volatile organic compounds (VOCs) and especially chlorinated VOCs (VOCls) are regarded as en viron mental risk substances in water bodies due to their toxic characteristics. Even in the atmosphere they highly impact atmospheric chemistry, e.g. degrading the ozone layer. Several studies have convincingly identified a number of natural VOCl sources thereby challenging the view of VOCls as only produced by humans. Yet, fundamental knowledge is still missing concerning the emission, distribution and the natural abundance of VOCls, especially regarding the high spatial and temporal variability of emissions from terrestrial sources. In the nuclear industry, Cl36 is a dosedominating radionuclide in some waste, and this adds to the need to better understand the processes, transport and fate of chlorine in the bio sphere. In this report 38 studies on VOCl flux measurement estimates were reviewed to summarize the current knowledge on spatiotemporal variations of different VOCls and various measurement tech niques.Chloromethane is the most studied VOCl compound and chloroform, the second most studied. A few other studies have estimated fluxes of additional VOCls such as tetrachloromethane (CCl4), methyl chloroform (CH3CCl3), tetrachloroethane (C2H2Cl4), freons (CFCs), chloroethane (C2H5Cl), bromodichloromethane (CHBrCl2). Studies were conducted in climates and terrestrial ecosystems ranging from arctic tundra to tropical rainforest but most studies focus on the temperate climate region. Wetlands and coastal systems dominate the studied ecosystems. Flux chambers are the most common method for investigation of the soilatmosphere exchange of VOCls, but a few studies used soil gas profiles and one the Relaxed Eddy Accumulation (REA) technique. Methodological uncertainties are mainly related to sample contamination, few replicates, chamber design, and chamber deployment (the time of measurement) effects on the soilatmosphere exchange itself. Despite the many challenges in measuring VOCls and estimating the fluxes, a substantial part of the chlorine in terrestrial ecosystems, and especially from wetlands and coastal areas, is emitted to the atmosphere as VOCls. In inland forested ecosystems, the release of Cl to the atmosphere could be as much as 0.1 g m–2, which is 40 % of the wet deposition and there are studies that suggest that freshwater wetlands are much larger source of chlorine in the atmosphere than previously understood.
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43. |
- Söderström, Mats
(author)
-
Modelling within-field variations in deoxynivalenol (DON) content in oats using proximal and remote sensing
- 2015
-
In: Precision Agriculture. - : Springer Science and Business Media LLC. - 1385-2256 .- 1573-1618. ; 16, s. 1-14
-
Journal article (peer-reviewed)abstract
- Within-field variations in the mycotoxin deoxynivalenol (DON) in oat grain were investigated at two farms in south-west Sweden. At Sarestad farm (sampled 2012), where one of two fields studied was ploughed annually and the other was under no-till cultivation, the DON concentration varied between 28 and 1 755 ppb. The level was higher (270-5 000 ppb) at Entorp farm (sampled 2013). Within-field prediction models for DON were constructed using a data mining method (multi-variate adaptive regression splines) with satellite data, an ECa sensor and airborne laser scanning. At Sarestad, the no-till field had higher DON content, with the highest values in silty patches in the otherwise clayey soil. Sensor data related to soil and crop conditions had the potential to describe the DON variability within fields. The covariance between DON content and auxiliary data differed at Entorp farm, where high DON values (> 2 000 ppb) were found in clayey parts of the field. This pattern was attributed to poor drainage with recurring waterlogging. Within these clayey parts, the highest DON contents coincided with the highest biomass density. South-west Sweden received much less rainfall in 2013 than in 2012, which may have resulted in different DON patterns in relation to soil types. In 2012, more permeable silty soils apparently promoted growth, biomass production and DON production, whereas in 2013 a poorly drained clayey soil with high water-holding capacity favoured development of high DON concentrations.
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44. |
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45. |
- Tedersoo, Leho, et al.
(author)
-
Novel soil-inhabiting clades fill gaps in the fungal tree of life
- 2017
-
In: Microbiome. - : Springer Science and Business Media LLC. - 2049-2618. ; 5
-
Journal article (peer-reviewed)abstract
- Background - Fungi are a diverse eukaryotic group of degraders, pathogens, and symbionts, with many lineages known only from DNA sequences in soil, sediments, air, and water. Results - We provide rough phylogenetic placement and principal niche analysis for >40 previously unrecognized fungal groups at the order and class level from global soil samples based on combined 18S (nSSU) and 28S (nLSU) rRNA gene sequences. Especially, Rozellomycota (Cryptomycota), Zygomycota s.lat, Ascomycota, and Basidiomycota are rich in novel fungal lineages, most of which exhibit distinct preferences for climate and soil pH. Conclusions - This study uncovers the great phylogenetic richness of previously unrecognized order- to phylum-level fungal lineages. Most of these rare groups are distributed in different ecosystems of the world but exhibit distinct ecological preferences for climate or soil pH. Across the fungal kingdom, tropical and non-tropical habitats are equally likely to harbor novel groups. We advocate that a combination of traditional and high-throughput sequencing methods enable efficient recovery and phylogenetic placement of such unknown taxonomic groups.
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46. |
- Barrios Latorre, Sergio Alejandro, et al.
(author)
-
Exploring the benefits of intermediate crops : Is it possible to offset soil organic carbon losses caused by crop residue removal?
- 2024
-
In: Agricultural Systems. - 0308-521X .- 1873-2267. ; 215
-
Journal article (peer-reviewed)abstract
- CONTEXT: Agriculture plays a central role as a feedstock provider for the bioeconomy. However, utilization competing with food production and associated land use change have previously been a matter of debate. Nonetheless, strengthening the productivity of agroecosystems through sustainable intensification can prevent the depletion of natural resources, enhance food security, and facilitate adaptation to and mitigation of climate change. OBJECTIVE: This study explores the effects of combining crop residue removal for use as biomass feedstock with the establishment of intermediate crops to compensate for organic carbon depletion in arable land in Sweden. METHODS: The analysis relied on Swedish national agricultural statistics at the highest available spatial resolution (yield survey district). Crop residue calculations factored in crop:residue ratios, and harvestable and recoverable potentials. A model was devised to estimate land availability for cultivating intermediate crops based on generalized crop rotation sequences, and a spatial interpolation was employed to determine oilseed radish yields as a model intermediate crop. Estimates of long-term soil carbon inputs hinged on biomass carbon content and humification coefficients dependent on soil clay content. RESULTS AND CONCLUSION: The total annual residual biomass availability in the country stands at approximately 2139 kt per year. The potential harvestable biomass production from intermediate crops was estimated at 383 kt per year. However, spatial differences were evident in total biomass production and effects on soil organic carbon inputs. For the majority of districts, the inclusion of intermediate crops could offset the negative effect of a complete removal of crop residues on soil organic carbon inputs. In other cases, establishing intermediate crops could not compensate for these negative effects, but some differences were observed when comparing the harvesting and the incorporation of the intermediate crops' biomass. Spatial disparities originated from variations in soil texture, intermediate crop yield, and rotation sequences. SIGNIFICANCE: This research is an attempt to address the challenge of maintaining and increasing the soil carbon stocks under the context of a growing biomass demand in a developing biobased economy. It highlights the divergent effects of combining crop residue removal with the inclusion of intermediate crops under distinct agroecological conditions in the Northern European context. By giving estimates on biomass availability and effects on soil organic carbon inputs, we provide information that can support decision making for bioeconomy planning and sustainable resource utilization. This also has long-term implications for preservation of soil fertility, agricultural productivity and climate change mitigation.
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47. |
- Englund, Oskar, et al.
(author)
-
Beneficial land use change: Strategic expansion of new biomass plantations can reduce environmental impacts from EU agriculture
- 2020
-
In: Global Environmental Change. - : Elsevier BV. - 0959-3780 .- 1872-9495. ; 60
-
Journal article (peer-reviewed)abstract
- Society faces the double challenge of increasing biomass production to meet the future demands for food, materials and bioenergy, while addressing negative impacts of current (and future) land use. In the discourse, land use change (LUC) has often been considered as negative, referring to impacts of deforestation and expansion of biomass plantations. However, strategic establishment of suitable perennial production systems in agricultural landscapes can mitigate environmental impacts of current crop production, while providing biomass for the bioeconomy. Here, we explore the potential for such “beneficial LUC” in EU28. First, we map and quantify the degree of accumulated soil organic carbon losses, soil loss by wind and water erosion, nitrogen emissions to water, and recurring floods, in ∼81.000 individual landscapes in EU28. We then estimate the effectiveness in mitigating these impacts through establishment of perennial plants, in each landscape. The results indicate that there is a substantial potential for effective impact mitigation. Depending on criteria selection, 10–46% of the land used for annual crop production in EU28 is located in landscapes that could be considered priority areas for beneficial LUC. These areas are scattered all over Europe, but there are notable “hot-spots” where priority areas are concentrated, e.g., large parts of Denmark, western UK, The Po valley in Italy, and the Danube basin. While some policy developments support beneficial LUC, implementation could benefit from attempts to realize synergies between different Sustainable Development Goals, e.g., “Zero hunger”, “Clean water and sanitation”, “Affordable and Clean Energy”, “Climate Action”, and “Life on Land”.
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48. |
- Englund, Oskar, et al.
(author)
-
Large-scale deployment of in-rotation grass cultivation as a multifunctional soil climate mitigation strategy
-
Other publication (other academic/artistic)abstract
- The agricultural sector can contribute to climate change mitigation by reducing its own greenhouse gas (GHG) emissions and sequestering atmospheric carbon in vegetation and soils, and by providing biomass for substituting fossil fuels and other GHG intensive products in the energy, industry and transport sectors. New policies at EU level provide incentives for more sustainable land use practices, for example, cultivation systems using perennial plants that provide biomass for food, bioenergy and other biobased products along with land carbon sequestration and other environmental benefits. Based on spatial modelling across more than 81,000 landscapes in Europe, we find that introduction of grass-clover leys into rotations with annual crops could result in soil organic carbon sequestration corresponding to 5-10% of total current GHG emissions from agriculture in EU27+UK, annually until 2050. The combined annual GHG savings from soil carbon sequestration and use of biogas produced in connection to grass-based biorefineries equals 13-48% of current GHG emissions from agriculture. The assessed environmental co-benefits (reduced wind and water erosion, reduced nitrogen emissions to water, and mitigation of impacts associated with flooding) are considerable. Besides policy instruments, new markets for grass biomass, e.g., as feedstock for producing biofuels and protein concentrate, can incentivize widespread deployment of in-rotation grass cultivation.
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49. |
- Hartmann, Martin, et al.
(author)
-
Significant and persistent impact of timber harvesting on soil microbial communities in Northern coniferous forests
- 2012
-
In: The ISME Journal. - : Springer Science and Business Media LLC. - 1751-7362 .- 1751-7370. ; 6:12, s. 2199-2218
-
Journal article (peer-reviewed)abstract
- Forest ecosystems have integral roles in climate stability, biodiversity and economic development. Soil stewardship is essential for sustainable forest management. Organic matter (OM) removal and soil compaction are key disturbances associated with forest harvesting, but their impacts on forest ecosystems are not well understood. Because microbiological processes regulate soil ecology and biogeochemistry, microbial community structure might serve as indicator of forest ecosystem status, revealing changes in nutrient and energy flow patterns before they have irreversible effects on long-term soil productivity. We applied massively parallel pyrosequencing of over 4.6 million ribosomal marker sequences to assess the impact of OM removal and soil compaction on bacterial and fungal communities in a field experiment replicated at six forest sites in British Columbia, Canada. More than a decade after harvesting, diversity and structure of soil bacterial and fungal communities remained significantly altered by harvesting disturbances, with individual taxonomic groups responding differentially to varied levels of the disturbances. Plant symbionts, like ectomycorrhizal fungi, and saprobic taxa, such as ascomycetes and actinomycetes, were among the most sensitive to harvesting disturbances. Given their significant ecological roles in forest development, the fate of these taxa might be critical for sustainability of forest ecosystems. Although abundant bacterial populations were ubiquitous, abundant fungal populations often revealed a patchy distribution, consistent with their higher sensitivity to the examined soil disturbances. These results establish a comprehensive inventory of bacterial and fungal community composition in northern coniferous forests and demonstrate the long-term response of their structure to key disturbances associated with forest harvesting.
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50. |
- Mjöfors, Kristina, et al.
(author)
-
Indications that site preparation increases forest ecosystem carbon stocks in the long term
- 2017
-
In: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 32:8, s. 717-725
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Journal article (peer-reviewed)abstract
- Mechanical site preparation (MSP) causes a mixing disturbance of the soil, which may increase decomposition of soil organic matter and subsequent carbon (C) dioxide emissions to the atmosphere. MSP also promotes the establishment and growth of tree seedlings, and hence ecosystem C fixation. However, there are uncertainties regarding the net effects of MSP on C stocks at the ecosystem scale. To assess decennial effects of MSP on ecosystem C stocks, C stocks in soil, ground vegetation and trees at three experimental forest sites with Pinus contorta, Pinus sylvestris and Picea abies in Sweden were sampled and measured for ca. 25 years in a control and after three MSP treatments: disc trenching, mounding and ploughing. After 25 years, all of the MSP treatments resulted in larger ecosystem C stocks than the control treatment due to positive effects on the tree biomass C stock. The tree C stock was highest after ploughing, intermediate after mounding or disc trenching and lowest in untreated control plots at all experimental sites. The MSP treatments did not affect the soil C stocks down to 30cm. We recommend mounding or disc trenching to promote C sequestration as they disturb sites’ ecological, aesthetic and recreation values less than ploughing.
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