Seasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern Sweden
Arctic ecosystems are sensitive to climate change and this biome is experiencing accelerated warming. Climate change in the arctic is projected to further alter precipitation and temperature patterns, which may influence land-water interactions in the future. Such changes have the potential to affec...
Main Author: | |
---|---|
Format: | Others |
Language: | English |
Published: |
Umeå universitet, Institutionen för ekologi, miljö och geovetenskap
2019
|
Subjects: | |
Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-155851 |
id |
ndltd-UPSALLA1-oai-DiVA.org-umu-155851 |
---|---|
record_format |
oai_dc |
spelling |
ndltd-UPSALLA1-oai-DiVA.org-umu-1558512019-02-02T06:10:01ZSeasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern SwedenengHauptmann, DemianUmeå universitet, Institutionen för ekologi, miljö och geovetenskap2019Climate changearctic ecosystemsnutrient limitationbiofilmresource limitationNatural SciencesNaturvetenskapEarth and Related Environmental SciencesGeovetenskap och miljövetenskapArctic ecosystems are sensitive to climate change and this biome is experiencing accelerated warming. Climate change in the arctic is projected to further alter precipitation and temperature patterns, which may influence land-water interactions in the future. Such changes have the potential to affect aquatic biofilm communities (i.e., algae, bacteria, and fungi) that form the base of riverine food webs, yet are sensitive to changes in thermal and light regimes, and are potentially limited by macronutrients like carbon (C), nitrogen (N) and phosphorus (P). This study investigated the patterns of resource limitation for autotrophic and heterotrophic biofilms in the Arctic using nutrient diffusing substrata (NDS) in a river network in northern Sweden (Miellajokka). Continuous NDS deployments (March until September) in a birch forest stream were combined with a spatial survey of nutrient limitation in late summer across 20 sites that encompassed a variety of nutrient, light, and temperature combinations. Results show that nutrient limitation of autotrophic processes was common during summer, but also that light inhibited algal growth in early season, and that temperature accelerated rates of activity throughout the growing season. By comparison, heterotrophic processes were less influenced by temperature, unless experimentally supplied with N and P. Alongside persistent N limitation, co-limitation by macronutrients (NP: autotrophic and heterotrophic biofilm, or CNP: heterotrophic biofilm) dominated the overall pattern of limitation over time and space. However, results from the spatial survey suggested that the identity of the primary limiting nutrient can change from N to P, based on differences in chemistry that arise from varying catchment features. As arctic studies are often conducted at individual sites during summer, they may miss shifts in the drivers of stream productivity that arise from variable nutrient, temperature, and light regimes. This study attempted to capture those changes and identify conditions where one might expect to see transitions in the relative importance of physical and chemical factors that limit biofilm development. These results also highlight the challenge of identifying the single most important limiting nutrient (e.g., N versus P) in streams and rivers across the Arctic, as I found that both nutrients could play this role within a single, relatively small drainage system. Student thesisinfo:eu-repo/semantics/bachelorThesistexthttp://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-155851application/pdfinfo:eu-repo/semantics/openAccess |
collection |
NDLTD |
language |
English |
format |
Others
|
sources |
NDLTD |
topic |
Climate change arctic ecosystems nutrient limitation biofilm resource limitation Natural Sciences Naturvetenskap Earth and Related Environmental Sciences Geovetenskap och miljövetenskap |
spellingShingle |
Climate change arctic ecosystems nutrient limitation biofilm resource limitation Natural Sciences Naturvetenskap Earth and Related Environmental Sciences Geovetenskap och miljövetenskap Hauptmann, Demian Seasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern Sweden |
description |
Arctic ecosystems are sensitive to climate change and this biome is experiencing accelerated warming. Climate change in the arctic is projected to further alter precipitation and temperature patterns, which may influence land-water interactions in the future. Such changes have the potential to affect aquatic biofilm communities (i.e., algae, bacteria, and fungi) that form the base of riverine food webs, yet are sensitive to changes in thermal and light regimes, and are potentially limited by macronutrients like carbon (C), nitrogen (N) and phosphorus (P). This study investigated the patterns of resource limitation for autotrophic and heterotrophic biofilms in the Arctic using nutrient diffusing substrata (NDS) in a river network in northern Sweden (Miellajokka). Continuous NDS deployments (March until September) in a birch forest stream were combined with a spatial survey of nutrient limitation in late summer across 20 sites that encompassed a variety of nutrient, light, and temperature combinations. Results show that nutrient limitation of autotrophic processes was common during summer, but also that light inhibited algal growth in early season, and that temperature accelerated rates of activity throughout the growing season. By comparison, heterotrophic processes were less influenced by temperature, unless experimentally supplied with N and P. Alongside persistent N limitation, co-limitation by macronutrients (NP: autotrophic and heterotrophic biofilm, or CNP: heterotrophic biofilm) dominated the overall pattern of limitation over time and space. However, results from the spatial survey suggested that the identity of the primary limiting nutrient can change from N to P, based on differences in chemistry that arise from varying catchment features. As arctic studies are often conducted at individual sites during summer, they may miss shifts in the drivers of stream productivity that arise from variable nutrient, temperature, and light regimes. This study attempted to capture those changes and identify conditions where one might expect to see transitions in the relative importance of physical and chemical factors that limit biofilm development. These results also highlight the challenge of identifying the single most important limiting nutrient (e.g., N versus P) in streams and rivers across the Arctic, as I found that both nutrients could play this role within a single, relatively small drainage system. |
author |
Hauptmann, Demian |
author_facet |
Hauptmann, Demian |
author_sort |
Hauptmann, Demian |
title |
Seasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern Sweden |
title_short |
Seasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern Sweden |
title_full |
Seasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern Sweden |
title_fullStr |
Seasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern Sweden |
title_full_unstemmed |
Seasonality of resource limitation of stream biofilm : Nutrient limitation of an arctic stream in northern Sweden |
title_sort |
seasonality of resource limitation of stream biofilm : nutrient limitation of an arctic stream in northern sweden |
publisher |
Umeå universitet, Institutionen för ekologi, miljö och geovetenskap |
publishDate |
2019 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-155851 |
work_keys_str_mv |
AT hauptmanndemian seasonalityofresourcelimitationofstreambiofilmnutrientlimitationofanarcticstreaminnorthernsweden |
_version_ |
1718969979290779648 |