The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem
Abstract Climate change and its warming effects on vegetation and soils are a widely recognized phenomenon. In addition to warming, the understorey vegetation in northern environments has been subjected to several environmental changes, such as increasing nitrogen (N) and other disturbances. This th...
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ftunivoulu:oai:oulu.fi:isbn978-952-62-1173-2 2023-07-30T04:03:18+02:00 The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem Manninen, O. (Outi) Tolvanen, A. (Anne) Kytöviita, M. (Minna-Maarit) 2016-05-17 application/pdf http://urn.fi/urn:isbn:9789526211732 eng eng Oulun yliopisto info:eu-repo/semantics/altIdentifier/pissn/0355-3191 info:eu-repo/semantics/altIdentifier/eissn/1796-220X info:eu-repo/semantics/openAccess © University of Oulu, 2016 compensation fertilization microbial biomass nitrogen immobilization plant functional types sexual reproduction simulated herbivory soil removal vegetative recovery kasvien funktionaaliset tyypit kasvullinen palautuminen kompensaatio lannoitus maaperän poisto mikrobibiomassa siemenellinen lisääntyminen simuloitu laidunnus typen sitoutuminen Empetrum Vaccinium info:eu-repo/semantics/doctoralThesis info:eu-repo/semantics/publishedVersion 2016 ftunivoulu 2023-07-08T19:53:34Z Abstract Climate change and its warming effects on vegetation and soils are a widely recognized phenomenon. In addition to warming, the understorey vegetation in northern environments has been subjected to several environmental changes, such as increasing nitrogen (N) and other disturbances. This thesis examines the effects of N-fertilization and disturbances on the vegetation biomass and abundance, plant community composition and plant, soil and microbial N and C pools. Seedling establishment of the most common dwarf shrubs (deciduous Vaccinium myrtillus, evergreens V. vitis-idaea and Empetrum nigrum ssp. hermaphroditum) was investigated after artificial disturbance treatments (vegetation and soil removal). These studies were conducted in the boreal and subarctic ecosystems and in the forest-tundra ecotone in northern Finland. N-fertilization and disturbances enhanced the amount of graminoids in plant communities, and the recovery ability of graminoids was enhanced after N-fertilization, which homogenized the vegetation and resulted in a new stable state in the plant community. The recovery ability of evergreen dwarf shrubs was low after disturbances. Disturbances created habitats for seed germination, but the seedling establishment of dwarf shrubs studied was still limited by seed availability. N-fertilization had no effect on microbial biomass. Instead, microbial biomass decreased with disturbance treatment in the boreal forest. However, the concentration of N increased in above-ground vegetation, both after N-fertilization and disturbance without any indication of N immobilization, suggesting that plant species captured the available N effectively for their recovery. The study shows that the likely outcome of N enrichment, when combined with disturbances, is the enhanced growth of graminoids. The seedling establishment does not compensate for the reduction of the vegetative recovery of evergreen dwarf shrubs, which makes evergreen dwarf shrubs sensitive to environmental changes. As the understorey is more ... Doctoral or Postdoctoral Thesis Empetrum nigrum Northern Finland Subarctic Tundra Jultika - University of Oulu repository |
institution |
Open Polar |
collection |
Jultika - University of Oulu repository |
op_collection_id |
ftunivoulu |
language |
English |
topic |
compensation fertilization microbial biomass nitrogen immobilization plant functional types sexual reproduction simulated herbivory soil removal vegetative recovery kasvien funktionaaliset tyypit kasvullinen palautuminen kompensaatio lannoitus maaperän poisto mikrobibiomassa siemenellinen lisääntyminen simuloitu laidunnus typen sitoutuminen Empetrum Vaccinium |
spellingShingle |
compensation fertilization microbial biomass nitrogen immobilization plant functional types sexual reproduction simulated herbivory soil removal vegetative recovery kasvien funktionaaliset tyypit kasvullinen palautuminen kompensaatio lannoitus maaperän poisto mikrobibiomassa siemenellinen lisääntyminen simuloitu laidunnus typen sitoutuminen Empetrum Vaccinium Manninen, O. (Outi) The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem |
topic_facet |
compensation fertilization microbial biomass nitrogen immobilization plant functional types sexual reproduction simulated herbivory soil removal vegetative recovery kasvien funktionaaliset tyypit kasvullinen palautuminen kompensaatio lannoitus maaperän poisto mikrobibiomassa siemenellinen lisääntyminen simuloitu laidunnus typen sitoutuminen Empetrum Vaccinium |
description |
Abstract Climate change and its warming effects on vegetation and soils are a widely recognized phenomenon. In addition to warming, the understorey vegetation in northern environments has been subjected to several environmental changes, such as increasing nitrogen (N) and other disturbances. This thesis examines the effects of N-fertilization and disturbances on the vegetation biomass and abundance, plant community composition and plant, soil and microbial N and C pools. Seedling establishment of the most common dwarf shrubs (deciduous Vaccinium myrtillus, evergreens V. vitis-idaea and Empetrum nigrum ssp. hermaphroditum) was investigated after artificial disturbance treatments (vegetation and soil removal). These studies were conducted in the boreal and subarctic ecosystems and in the forest-tundra ecotone in northern Finland. N-fertilization and disturbances enhanced the amount of graminoids in plant communities, and the recovery ability of graminoids was enhanced after N-fertilization, which homogenized the vegetation and resulted in a new stable state in the plant community. The recovery ability of evergreen dwarf shrubs was low after disturbances. Disturbances created habitats for seed germination, but the seedling establishment of dwarf shrubs studied was still limited by seed availability. N-fertilization had no effect on microbial biomass. Instead, microbial biomass decreased with disturbance treatment in the boreal forest. However, the concentration of N increased in above-ground vegetation, both after N-fertilization and disturbance without any indication of N immobilization, suggesting that plant species captured the available N effectively for their recovery. The study shows that the likely outcome of N enrichment, when combined with disturbances, is the enhanced growth of graminoids. The seedling establishment does not compensate for the reduction of the vegetative recovery of evergreen dwarf shrubs, which makes evergreen dwarf shrubs sensitive to environmental changes. As the understorey is more ... |
author2 |
Tolvanen, A. (Anne) Kytöviita, M. (Minna-Maarit) |
format |
Doctoral or Postdoctoral Thesis |
author |
Manninen, O. (Outi) |
author_facet |
Manninen, O. (Outi) |
author_sort |
Manninen, O. (Outi) |
title |
The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem |
title_short |
The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem |
title_full |
The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem |
title_fullStr |
The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem |
title_full_unstemmed |
The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem |
title_sort |
resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem |
publisher |
Oulun yliopisto |
publishDate |
2016 |
url |
http://urn.fi/urn:isbn:9789526211732 |
genre |
Empetrum nigrum Northern Finland Subarctic Tundra |
genre_facet |
Empetrum nigrum Northern Finland Subarctic Tundra |
op_relation |
info:eu-repo/semantics/altIdentifier/pissn/0355-3191 info:eu-repo/semantics/altIdentifier/eissn/1796-220X |
op_rights |
info:eu-repo/semantics/openAccess © University of Oulu, 2016 |
_version_ |
1772814278830587904 |