H. Hilmarsson, Magnus Göransson, Jón Hallsteinn Hallsson, Þ. A. Kristjánsdóttir, Jónatan Hermannsson
{"title":"Effect of soil type on barley yields in Icelandic cultivar trials","authors":"H. Hilmarsson, Magnus Göransson, Jón Hallsteinn Hallsson, Þ. A. Kristjánsdóttir, Jónatan Hermannsson","doi":"10.16886/IAS.2017.08","DOIUrl":"https://doi.org/10.16886/IAS.2017.08","url":null,"abstract":"","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"30 1","pages":"73-76"},"PeriodicalIF":0.5,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Mandáková, Hjörtur Thorbjörnsson, Rahul Pisupati, I. Reichardt, M. Lysak, K. Anamthawat-Jónsson
In this paper, we report the first discovery of Arabidopsis thaliana in Iceland. In May 2015, the plants were located growing on warm geothermal soil around the hot spring Deildartunguhver in Reykholt, West Iceland. Flower buds and leaves were collected and used for subsequent cytogenetic analyses and DNA sequencing. Whole plant specimens were deposited at the Icelandic AMNH herbarium and were assigned accession number VA21379. The accession was found to be diploid with 2n=2x=10, as expected for this species. At meiosis I (diakinesis) it formed five normal bivalents. Ribosomal FISH mapping revealed two pairs of 5S rDNA loci and two pairs of NORs. Fine-scale chromosome painting using BAC clones specific for chromosomes At1 and At4 confirmed the standard structure of these chromosomes. Furthermore, the painting revealed an absence of the 1.17-Mb paracentric inversion on the At4 short arm in the Icelandic accession, in contrast to the inversion-bearing A. thaliana accessions more prevalent in North America. The sequencing of multiplexed whole-genome libraries identified the Swedish accession Ham-1 as the closest relative of the Icelandic accession, with, however, a markedly low SNPmatch score. We conclude that although the Icelandic accession appears to be more genetically related to populations from Scandinavia than to other European accessions, it did not originate from any of the populations represented in the global collection of the 1001 Genomes accessions of A. thaliana.
{"title":"Icelandic accession of Arabidopsis thaliana confirmed with cytogenetic markers and its origin inferred from whole-genome sequencing","authors":"T. Mandáková, Hjörtur Thorbjörnsson, Rahul Pisupati, I. Reichardt, M. Lysak, K. Anamthawat-Jónsson","doi":"10.16886/IAS.2017.03","DOIUrl":"https://doi.org/10.16886/IAS.2017.03","url":null,"abstract":"In this paper, we report the first discovery of Arabidopsis thaliana in Iceland. In May 2015, the plants were located growing on warm geothermal soil around the hot spring Deildartunguhver in Reykholt, West Iceland. Flower buds and leaves were collected and used for subsequent cytogenetic analyses and DNA sequencing. Whole plant specimens were deposited at the Icelandic AMNH herbarium and were assigned accession number VA21379. The accession was found to be diploid with 2n=2x=10, as expected for this species. At meiosis I (diakinesis) it formed five normal bivalents. Ribosomal FISH mapping revealed two pairs of 5S rDNA loci and two pairs of NORs. Fine-scale chromosome painting using BAC clones specific for chromosomes At1 and At4 confirmed the standard structure of these chromosomes. Furthermore, the painting revealed an absence of the 1.17-Mb paracentric inversion on the At4 short arm in the Icelandic accession, in contrast to the inversion-bearing A. thaliana accessions more prevalent in North America. The sequencing of multiplexed whole-genome libraries identified the Swedish accession Ham-1 as the closest relative of the Icelandic accession, with, however, a markedly low SNPmatch score. We conclude that although the Icelandic accession appears to be more genetically related to populations from Scandinavia than to other European accessions, it did not originate from any of the populations represented in the global collection of the 1001 Genomes accessions of A. thaliana.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"30 1","pages":"29-38"},"PeriodicalIF":0.5,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The sustainability of sheep grazing in Iceland has been repeatedly questioned as in some areas high stocking rates have been associated with extensive soil erosion and ecosystem degradation. We synthesized all available information on the effects of sheep grazing on vegetation, soil properties and other organisms in the rangelands of Iceland, with special focus on the grey literature. We compiled 347 documents, but only 44 contained extractable data, reporting on 16 studies. The scarcity of studies prevented us from drawing general conclusions for most ecological variables across environmental conditions, but some consistent trends were found. The extent of bare ground was significantly higher in grazed areas and grazing affected plant community structure. The potential for increased soil erosion in grazed areas remains a problem in Icelandic rangelands. A better understanding of the ecological impacts of sheep grazing is required to inform sustainable grazing practices adapted to the local conditions of this region.
{"title":"Assessing the Ecological Impacts of Extensive Sheep Grazing in Iceland","authors":"Bryndís Marteinsdóttir, I. Barrio, I. Jónsdóttir","doi":"10.16886/IAS.2017.07","DOIUrl":"https://doi.org/10.16886/IAS.2017.07","url":null,"abstract":"The sustainability of sheep grazing in Iceland has been repeatedly questioned as in some areas high stocking rates have been associated with extensive soil erosion and ecosystem degradation. We synthesized all available information on the effects of sheep grazing on vegetation, soil properties and other organisms in the rangelands of Iceland, with special focus on the grey literature. We compiled 347 documents, but only 44 contained extractable data, reporting on 16 studies. The scarcity of studies prevented us from drawing general conclusions for most ecological variables across environmental conditions, but some consistent trends were found. The extent of bare ground was significantly higher in grazed areas and grazing affected plant community structure. The potential for increased soil erosion in grazed areas remains a problem in Icelandic rangelands. A better understanding of the ecological impacts of sheep grazing is required to inform sustainable grazing practices adapted to the local conditions of this region.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"30 1","pages":"55-72"},"PeriodicalIF":0.5,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effect of harbour seal predation on salmonids has been frequently debated, although interactions between these species have never been thoroughly investigated in Icelandic waters prior to this ...
{"title":"Diet of harbour seals in a salmon estuary in North-West Iceland","authors":"S. M. Granquist, E. Hauksson","doi":"10.16886/IAS.2016.02","DOIUrl":"https://doi.org/10.16886/IAS.2016.02","url":null,"abstract":"The effect of harbour seal predation on salmonids has been frequently debated, although interactions between these species have never been thoroughly investigated in Icelandic waters prior to this ...","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"29 1","pages":"7-19"},"PeriodicalIF":0.5,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Davidsdottir, T. G. Gunnarsson, G. Halldorsson, B. Sigurdsson
Degradation of ecosystems and introductions of invasive species pose a threat to global biodiversity. Ecosystem restoration and revegetation actions are important for amending habitat loss and for the protection of species of plants and animals. Iceland has the highest rate of soil erosion and desertification in Northern Europe and counteractions to erosion and revegetation measures have taken place for over a century. We studied the effect of revegetation on the density and composition of birds and invertebrate abundance in 26 survey areas comparing: a) unvegetated eroded areas, b) native heathlands restored on eroded land, and c) revegetation by the introduced and exotic Nootka lupin (Lupinus nootkatensis) on eroded land. Birds were counted on transects and invertebrates sampled with a sweep net. Both revegetation methods greatly increased the abundance of birds. The highest total numbers of invertebrates and birds were recorded on land revegetated with Nootka lupin. On average 31 birds km -2 were recorded on barren land, 337 on heathland and 627 in Nootka lupin. Bird species composition differed between the two revegetation methods. Restored heathland provided habitat for waders of internationally decreasing populations, whereas Nootka lupin stands harboured more common bird species. Golden Plover (Pluvialis apricaria) and Dunlin (Calidris alpina) were most common on restored heathland, while Snipe (Gallinago gallinago) and Meadow Pipit (Anthus pratensis) were most common in Nootka lupine. The abundance of birds was positively correlated with that of invertebrates. The abundance of different bird species differed by successional stage in each habitat. The study showed the generally positive effects of revegetation on animal biodiversity and also how different revegetation methods produce different trajectories of ecosystem development.
{"title":"Avian abundance and communities in areas revegetated with exotic versus native plant species","authors":"B. Davidsdottir, T. G. Gunnarsson, G. Halldorsson, B. Sigurdsson","doi":"10.16886/IAS.2016.03","DOIUrl":"https://doi.org/10.16886/IAS.2016.03","url":null,"abstract":"Degradation of ecosystems and introductions of invasive species pose a threat to global biodiversity. Ecosystem restoration and revegetation actions are important for amending habitat loss and for the protection of species of plants and animals. Iceland has the highest rate of soil erosion and desertification in Northern Europe and counteractions to erosion and revegetation measures have taken place for over a century. We studied the effect of revegetation on the density and composition of birds and invertebrate abundance in 26 survey areas comparing: a) unvegetated eroded areas, b) native heathlands restored on eroded land, and c) revegetation by the introduced and exotic Nootka lupin (Lupinus nootkatensis) on eroded land. Birds were counted on transects and invertebrates sampled with a sweep net. Both revegetation methods greatly increased the abundance of birds. The highest total numbers of invertebrates and birds were recorded on land revegetated with Nootka lupin. On average 31 birds km -2 were recorded on barren land, 337 on heathland and 627 in Nootka lupin. Bird species composition differed between the two revegetation methods. Restored heathland provided habitat for waders of internationally decreasing populations, whereas Nootka lupin stands harboured more common bird species. Golden Plover (Pluvialis apricaria) and Dunlin (Calidris alpina) were most common on restored heathland, while Snipe (Gallinago gallinago) and Meadow Pipit (Anthus pratensis) were most common in Nootka lupine. The abundance of birds was positively correlated with that of invertebrates. The abundance of different bird species differed by successional stage in each habitat. The study showed the generally positive effects of revegetation on animal biodiversity and also how different revegetation methods produce different trajectories of ecosystem development.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"29 1","pages":"21-37"},"PeriodicalIF":0.5,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aim of this paper is to report cases of the intestinal parasitic nematode Strongyloides stercoralis in dogs in Iceland. The nematode was diagnosed in 20 (0.6%) of imported dogs in quaratine in Iceland during 19892016. Household dogs: The first case of S. stercoralis infection diagnosed outside quaratine in Iceland was in an unhealthy household puppy purchased from an Icelandic breeding kennel (Kennel A) in 2012. A total of nine puppies purchased from Kennel A, and two dogs which had contact with dogs from the kennel, were diagnosed with S. stercoralis. Kennel dogs: In 2012 S. stercoralis was confirmed in dozens of dogs in Kennel A. Follow-up examinations after anthelmintic treatments indicated a successful removal of worms in imported and household dogs. In spite of more than a dozen anthelmintic treatment actions and other arrangements in Kennel A since 2012, recurrent infections have repeatedly been confirmed, the last one in 2015. The nematode is believed to have been introduced to the breeding kennel with an imported dog, in spite of anthelmintic treatments in quarantine. YFIRLIT Sníkjuþráðormurinn Strongyloides stercoralis staðfestur á Íslandi í innfluttum hundum, heimilishundum og í hundaræktunarstöð. Markmið þessa yfirlits er að greina frá tilfellum sem greinst hafa af sníkjuþráðorminum Strongyloides stercoralis í hundum á Íslandi. Ormurinn hefur greinst í saursýnum úr 20 (0.6%) hundum sem fluttir voru til landins um einungrunarstöðvar á árunum 1989-2016. Heimilishundar: Fyrsta tilfelli utan einangrunarstöðva greindist í veikum heimilishvolpi sem keyptur var á íslenskri hundaræktunarstöð 2012. Ormurinn greindist í alls níu hvolpum sem keyptir voru á stöðinni og í tveimur heimilishundum sem höfðu haft samgang við hunda frá stöðinni. Hundaræktunarstöðin: S. stercoralis greindist í tugum hunda í stöðinni í byrjun árs 2012, bæði í hvolpum og fullorðnum hundum. Innfluttu hundarnir og heimilishundarnir fengu ormalyfjameðferð og eftirfylgnirannsóknir bentu til að tekist hefði að uppræta ormana. Margendurteknar ormalyfjagjafir á árunum 2012 -2016 og aðrar aðgerðir í hundaræktunarstöðinni virðast hafa borið umtalsverðan árangur en ormurinn hefur þó greinst í stökum saursýnum á undanförnum árum, síðast í nóvember 2015. Talið er að þráðormurinn hafi borist inn í hundaræktunarstöðina með innfluttum hundi, þrátt fyrir endurteknar ormalyfjagjafir í einangrunarstöð, smitast milli hunda í ræktunarstöðinni og borist þaðan út með seldum hundum.
本文的目的是报告冰岛犬肠寄生线虫的病例。1989 - 2016年期间，在冰岛检疫的20只进口狗(0.6%)中诊断出了线虫。家庭犬:冰岛第一例在检疫外诊断出的粪球菌感染病例发生在2012年从冰岛育种犬舍(犬舍A)购买的一只不健康的家庭幼犬身上。从A狗舍购买的9只幼犬和与该狗舍的狗有过接触的2只狗被诊断患有粪球菌。犬只:2012年，a犬只的几十只狗被证实感染了粪虫绦虫，在驱虫治疗后的后续检查表明，进口和家养狗的蠕虫已被成功清除。尽管自2012年以来在a犬舍采取了十多次驱虫治疗行动和其他安排，但反复确认感染，最后一次是在2015年。尽管在隔离期间进行了驱虫治疗，但据信该线虫是与一只进口狗一起被引入繁殖犬舍的。YFIRLIT Sníkjuþráðormurinn粪圆线虫stazhusur Íslandi í influutum hundum, heimilishundum og í hundaræktunarstöð。Markmið þessa yfirliits er adð greina from tilfellum sem grest hafa at sníkjuþráðorminum粪圆线虫í hundum Íslandi。Ormurinn hefur greinst í saursýnum úr 20 (0.6%) humum sem flutitir voru til landing um einungrunarstöðvar árunum 1989-2016。Heimilishundar: Fyrsta tilfelli utan einangrunarstöðva greinddist í veikum heimilishvolpi sem keypturr var íslenskri hundaræktunarstöð 2012。Ormurinn greindist í all níu hvolpum sem keyptir voru stöðinni og í tveimur heimilishundum sem höfðu haft samgang við hunda fr stöðinni。Hundaræktunarstöðin: S. stercoralis greindist í tugum hunda í stöðinni í byrjun árs 2012, bæði í hvolpum og fuller - num hundum。Innfluttu hundarnir og heimilishundarnir fengu ormalyfjame_ ferð og eftirfylgnirannsóknir bentu til að tekist hefði að upr æta ormana。Margendurteknar ormalyfjagjafir árunum 2012 -2016 og a / rar a / ger / ir í hundaræktunarstöðinni vir / ast hafa borið umtalsver / an árangur en ormurinn hefur þó greinst í stökum saursýnum undanförnum árum, síðast í nóvember 2015。Talið er að þráðormurinn hafi borist inn í hundaræktunarstöðina með inflututum hundi， þrátt fyrir endurteknar ormalyfjagjafir í einangrunarstöð， smitast milli hunda í ræktunarstöðinni og borist þaðan út með seldum hundm。
{"title":"Strongyloides stercoralis found in imported dogs, household dogs and kennel dogs in Iceland","authors":"M. Eydal, K. Skírnisson","doi":"10.16886/IAS.2016.04","DOIUrl":"https://doi.org/10.16886/IAS.2016.04","url":null,"abstract":"The aim of this paper is to report cases of the intestinal parasitic nematode Strongyloides stercoralis in dogs in Iceland. The nematode was diagnosed in 20 (0.6%) of imported dogs in quaratine in Iceland during 19892016. Household dogs: The first case of S. stercoralis infection diagnosed outside quaratine in Iceland was in an unhealthy household puppy purchased from an Icelandic breeding kennel (Kennel A) in 2012. A total of nine puppies purchased from Kennel A, and two dogs which had contact with dogs from the kennel, were diagnosed with S. stercoralis. Kennel dogs: In 2012 S. stercoralis was confirmed in dozens of dogs in Kennel A. Follow-up examinations after anthelmintic treatments indicated a successful removal of worms in imported and household dogs. In spite of more than a dozen anthelmintic treatment actions and other arrangements in Kennel A since 2012, recurrent infections have repeatedly been confirmed, the last one in 2015. The nematode is believed to have been introduced to the breeding kennel with an imported dog, in spite of anthelmintic treatments in quarantine. YFIRLIT Sníkjuþráðormurinn Strongyloides stercoralis staðfestur á Íslandi í innfluttum hundum, heimilishundum og í hundaræktunarstöð. Markmið þessa yfirlits er að greina frá tilfellum sem greinst hafa af sníkjuþráðorminum Strongyloides stercoralis í hundum á Íslandi. Ormurinn hefur greinst í saursýnum úr 20 (0.6%) hundum sem fluttir voru til landins um einungrunarstöðvar á árunum 1989-2016. Heimilishundar: Fyrsta tilfelli utan einangrunarstöðva greindist í veikum heimilishvolpi sem keyptur var á íslenskri hundaræktunarstöð 2012. Ormurinn greindist í alls níu hvolpum sem keyptir voru á stöðinni og í tveimur heimilishundum sem höfðu haft samgang við hunda frá stöðinni. Hundaræktunarstöðin: S. stercoralis greindist í tugum hunda í stöðinni í byrjun árs 2012, bæði í hvolpum og fullorðnum hundum. Innfluttu hundarnir og heimilishundarnir fengu ormalyfjameðferð og eftirfylgnirannsóknir bentu til að tekist hefði að uppræta ormana. Margendurteknar ormalyfjagjafir á árunum 2012 -2016 og aðrar aðgerðir í hundaræktunarstöðinni virðast hafa borið umtalsverðan árangur en ormurinn hefur þó greinst í stökum saursýnum á undanförnum árum, síðast í nóvember 2015. Talið er að þráðormurinn hafi borist inn í hundaræktunarstöðina með innfluttum hundi, þrátt fyrir endurteknar ormalyfjagjafir í einangrunarstöð, smitast milli hunda í ræktunarstöðinni og borist þaðan út með seldum hundum.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"29 1","pages":"39-51"},"PeriodicalIF":0.5,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Sigurdsson, N. Leblans, S. Dauwe, Elín Guðmundsdóttir, P. Gundersen, G. Gunnarsdóttir, M. Holmstrup, K. Ilieva-Makulec, T. Kätterer, Bryndís Marteinsdóttir, M. Maljanen, E. Oddsdóttir, I. Ostonen, J. Peñuelas, C. Poeplau, Andreas Richter, Páll Sigurðsson, P. Bodegom, H. Wallander, J. Weedon, I. Janssens
This article describes how natural geothermal soil temperature gradients in Iceland have been used to study terrestrial ecosystem responses to soil warming. The experimental approach was evaluated at three study sites in southern Iceland; one grassland site that has been warm for at least 50 years (GO), and another comparable grassland site (GN) and a Sitka spruce plantation (FN) site that have both been warmed since an earthquake took place in 2008. Within each site type, five ca. 50 m long transects, with six permanent study plots each, were established across the soil warming gradients, spanning from unwarmed control conditions to gradually warmer soils. It was attempted to select the plots so the annual warming levels would be ca. +1, +3, +5, +10 and +20 °C within each transect. Results of continuous measurements of soil temperature (Ts) from 2013-2015 revealed that the soil warming was relatively constant and followed the seasonal Ts cycle of the unwarmed control plots. Volumetric water content in the top 5 cm of soil was repeatedly surveyed during 2013-2016. The grassland soils were wetter than the FN soils, but they had sometimes some significant warming-induced drying in the surface layer of the warmest plots, in contrast to FN. Soil chemistry did not show any indications that geothermal water had reached the root zone, but soil pH did increase somewhat with warming, which was probably linked to vegetation changes. As expected, the potential decomposition rate of organic matter increased significantly with warming. It was concluded that the natural geothermal gradients at the ForHot sites in Iceland offered realistic conditions for studying terrestrial ecosystem responses to warming with minimal artefacts.
{"title":"Geothermal ecosystems as natural climate change experiments: The ForHot research site in Iceland as a case study","authors":"B. Sigurdsson, N. Leblans, S. Dauwe, Elín Guðmundsdóttir, P. Gundersen, G. Gunnarsdóttir, M. Holmstrup, K. Ilieva-Makulec, T. Kätterer, Bryndís Marteinsdóttir, M. Maljanen, E. Oddsdóttir, I. Ostonen, J. Peñuelas, C. Poeplau, Andreas Richter, Páll Sigurðsson, P. Bodegom, H. Wallander, J. Weedon, I. Janssens","doi":"10.16886/IAS.2016.05","DOIUrl":"https://doi.org/10.16886/IAS.2016.05","url":null,"abstract":"This article describes how natural geothermal soil temperature gradients in Iceland have been used to study terrestrial ecosystem responses to soil warming. The experimental approach was evaluated at three study sites in southern Iceland; one grassland site that has been warm for at least 50 years (GO), and another comparable grassland site (GN) and a Sitka spruce plantation (FN) site that have both been warmed since an earthquake took place in 2008. Within each site type, five ca. 50 m long transects, with six permanent study plots each, were established across the soil warming gradients, spanning from unwarmed control conditions to gradually warmer soils. It was attempted to select the plots so the annual warming levels would be ca. +1, +3, +5, +10 and +20 °C within each transect. Results of continuous measurements of soil temperature (Ts) from 2013-2015 revealed that the soil warming was relatively constant and followed the seasonal Ts cycle of the unwarmed control plots. Volumetric water content in the top 5 cm of soil was repeatedly surveyed during 2013-2016. The grassland soils were wetter than the FN soils, but they had sometimes some significant warming-induced drying in the surface layer of the warmest plots, in contrast to FN. Soil chemistry did not show any indications that geothermal water had reached the root zone, but soil pH did increase somewhat with warming, which was probably linked to vegetation changes. As expected, the potential decomposition rate of organic matter increased significantly with warming. It was concluded that the natural geothermal gradients at the ForHot sites in Iceland offered realistic conditions for studying terrestrial ecosystem responses to warming with minimal artefacts.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"29 1","pages":"53-71"},"PeriodicalIF":0.5,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Atlason, Karl Martin Kjærheim, B. Davidsdottir, K. Ragnarsdóttir
This study compares the energy return on investment (EROI) of organic and conventional farms in Iceland. It examines which farming method returns the highest amount of edible energy to society relative to the input required. Twenty farms were studied: two organic and 18 conventional. Real data were gathered directly from five farms (including both of the organic farms in the study). Further data from 15 conventional dairy farms of different sizes were collected from a database maintained by the Icelandic Farmers Association. One of the organic farms studied (Org1) was found to have an EROI of 2.68, whereas two conventional farms used as controls for comparison (Con1-a and Con1-b) had EROIs of 0.60 and 0.69, respectively. The second organic farm (Org2) had an EROI of 0.55, versus the control farm ratio of 0.27. On average, large (<170 hectares) conventional dairy farms had an EROI of 0.65, while medium (<70 hectares) and small (<40 hectares) conventional farms had average EROIs of 0.56 and 0.50, respectively. This limited analysis suggests that organic dairy farms may provide better EROIs than conventional farms, but that their dairy yields per hectare are lower.
{"title":"A comparative analysis of the energy return on investment of organic and conventional Icelandic dairy farms.","authors":"R. Atlason, Karl Martin Kjærheim, B. Davidsdottir, K. Ragnarsdóttir","doi":"10.16886/IAS.2015.04","DOIUrl":"https://doi.org/10.16886/IAS.2015.04","url":null,"abstract":"This study compares the energy return on investment (EROI) of organic and conventional farms in Iceland. It examines which farming method returns the highest amount of edible energy to society relative to the input required. Twenty farms were studied: two organic and 18 conventional. Real data were gathered directly from five farms (including both of the organic farms in the study). Further data from 15 conventional dairy farms of different sizes were collected from a database maintained by the Icelandic Farmers Association. One of the organic farms studied (Org1) was found to have an EROI of 2.68, whereas two conventional farms used as controls for comparison (Con1-a and Con1-b) had EROIs of 0.60 and 0.69, respectively. The second organic farm (Org2) had an EROI of 0.55, versus the control farm ratio of 0.27. On average, large (<170 hectares) conventional dairy farms had an EROI of 0.65, while medium (<70 hectares) and small (<40 hectares) conventional farms had average EROIs of 0.56 and 0.50, respectively. This limited analysis suggests that organic dairy farms may provide better EROIs than conventional farms, but that their dairy yields per hectare are lower.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"28 1","pages":"29-42"},"PeriodicalIF":0.5,"publicationDate":"2015-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
INTRODUCTION Past volcanic eruptions in Iceland have sometimes led to long-distance distribution of fine volcanic tephra (volcanic ash). Evidence for volcanic ash from, for example, the ca. 4250 BP eruption in Hekla (H4) and the 17831784 AD Laki eruption in southern Iceland has been found in wetlands at Svalbard (Kekonen et al. 2005), Scotland (Charman et al. 1995) and Scandinavia (Thorarinsson 1981). Basaltic volcanic ash contains several compounds, e.g. mixed sulphates, ammonium (NH4 +) and nitrate (NO3 -) (Ayris and Delmelle 2012), all of which have the potential to affect various soil processes, such as N cycling and greenhouse gas (GHG) production. Such direct effects of long distance volcanic ash transport have, however, been little studied so far. The Eyjafjallajokull volcano eruption started in Iceland in March, 2010. A major outbreak of the central crater under the covering ice cap started on 14 April and continued until 24 May, ejecting a very large amount of gases and fine ash into the atmosphere. This ash contained mainly silicon dioxide, but also other compounds including sulphates (O’Dowd et al. 2012). This eruption gave us an opportunity to study the fresh volcanic ash and its effects on soil properties. Because this volcanic ash was alkaline, it could increase soil pH and affect the microbiological processes behind GHG emissions in a similar way to that suggested for wood ash (Maljanen et al. 2014, Klemedtsson et al. 2010). We used fresh volcanic ash from the Eyjafjallajokull volcano in a laboratory experiment conducted on samples of drained peat soil from western Finland that were also used for studying the effects of wood ash recycling from bioenergy power plants (Maljanen et al. 2014). The aim of this study was to test whether this volcanic ash affected GHG production rates in drained peat soil in our laboratory incubation experiments and to compare the results with wood ash.
冰岛过去的火山爆发有时会导致细小的火山火山灰远距离分布。例如，在斯瓦尔巴群岛(Kekonen et al. 2005)、苏格兰(Charman et al. 1995)和斯堪的纳维亚(Thorarinsson 1981)的湿地中发现了大约4250 BP的Hekla火山喷发(H4)和公元17831784年冰岛南部Laki火山喷发的火山灰证据。玄武岩火山灰含有多种化合物，如混合硫酸盐、铵(NH4 +)和硝酸盐(NO3 -) (Ayris和Delmelle 2012)，所有这些都有可能影响各种土壤过程，如氮循环和温室气体(GHG)产生。然而，到目前为止，对远距离火山灰运输的这种直接影响的研究还很少。2010年3月，冰岛埃亚菲亚德拉火山爆发。4月14日开始，一直持续到5月24日，冰盖下的中央火山口发生了一次大爆发，向大气中喷射出大量气体和细火山灰。这种灰烬主要含有二氧化硅，但也含有硫酸盐等其他化合物(O 'Dowd et al. 2012)。这次喷发使我们有机会研究新鲜的火山灰及其对土壤性质的影响。由于这种火山灰是碱性的，它可能会增加土壤pH值，并以类似于木灰的方式影响温室气体排放背后的微生物过程(Maljanen et al. 2014, Klemedtsson et al. 2010)。我们在实验室实验中使用了来自Eyjafjallajokull火山的新鲜火山灰，对芬兰西部的排水泥炭土样本进行了实验，该样本也用于研究生物能源发电厂木灰回收的影响(Maljanen et al. 2014)。本研究的目的是在我们的实验室孵化实验中测试这种火山灰是否影响排干泥炭土的温室气体产生速率，并将结果与木灰进行比较。
{"title":"Effect of volcanic ash on GHG production rates and soil properties in a drained peat soil compared to wood ash","authors":"M. Maljanen, M. Liimatainen, B. Sigurdsson","doi":"10.16886/IAS.2015.03","DOIUrl":"https://doi.org/10.16886/IAS.2015.03","url":null,"abstract":"INTRODUCTION Past volcanic eruptions in Iceland have sometimes led to long-distance distribution of fine volcanic tephra (volcanic ash). Evidence for volcanic ash from, for example, the ca. 4250 BP eruption in Hekla (H4) and the 17831784 AD Laki eruption in southern Iceland has been found in wetlands at Svalbard (Kekonen et al. 2005), Scotland (Charman et al. 1995) and Scandinavia (Thorarinsson 1981). Basaltic volcanic ash contains several compounds, e.g. mixed sulphates, ammonium (NH4 +) and nitrate (NO3 -) (Ayris and Delmelle 2012), all of which have the potential to affect various soil processes, such as N cycling and greenhouse gas (GHG) production. Such direct effects of long distance volcanic ash transport have, however, been little studied so far. The Eyjafjallajokull volcano eruption started in Iceland in March, 2010. A major outbreak of the central crater under the covering ice cap started on 14 April and continued until 24 May, ejecting a very large amount of gases and fine ash into the atmosphere. This ash contained mainly silicon dioxide, but also other compounds including sulphates (O’Dowd et al. 2012). This eruption gave us an opportunity to study the fresh volcanic ash and its effects on soil properties. Because this volcanic ash was alkaline, it could increase soil pH and affect the microbiological processes behind GHG emissions in a similar way to that suggested for wood ash (Maljanen et al. 2014, Klemedtsson et al. 2010). We used fresh volcanic ash from the Eyjafjallajokull volcano in a laboratory experiment conducted on samples of drained peat soil from western Finland that were also used for studying the effects of wood ash recycling from bioenergy power plants (Maljanen et al. 2014). The aim of this study was to test whether this volcanic ash affected GHG production rates in drained peat soil in our laboratory incubation experiments and to compare the results with wood ash.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"28 1","pages":"25-28"},"PeriodicalIF":0.5,"publicationDate":"2015-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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