The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta
The Mackenzie River Delta is a major outlet to the Arctic Ocean, an important habitat for freshwater organisms, migratory birds, and mammals, and a critical economic and social resource for the Gwich'in and Inuvialuit people. The Delta is also sensitive to climate change, with an increased like...
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ftyorkuniv:oai:yorkspace.library.yorku.ca:10315/39053 2023-05-15T14:53:11+02:00 The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta Scott, Ryan William Sharma, Sapna 2022-03-03T13:56:57Z application/pdf http://hdl.handle.net/10315/39053 en eng http://hdl.handle.net/10315/39053 Author owns copyright, except where explicitly noted. Please contact the author directly with licensing requests. Wildlife conservation Arctic Mackenzie Delta Benthos Benthic macroinvertebrates Biomonitoring Metacommunities Climate change Electronic Thesis or Dissertation 2022 ftyorkuniv 2022-08-22T13:08:15Z The Mackenzie River Delta is a major outlet to the Arctic Ocean, an important habitat for freshwater organisms, migratory birds, and mammals, and a critical economic and social resource for the Gwich'in and Inuvialuit people. The Delta is also sensitive to climate change, with an increased likelihood of more variable discharge and rising sea levels, leading to forecasts of increasing isolation of many high-elevation floodplain lakes and increasing connectivity of low-elevation lakes. While extensive and ongoing studies of the biogeochemistry of these lakes exist, lower secondary producers such as macroinvertebrates represent an overlooked element of the Mackenzie Delta ecosystem. The objective of this thesis is to identify the effects of flooding on the limnology and benthic invertebrate ecology of this climate-sensitive Arctic region. This thesis addresses this knowledge gap by examining responses of lake water chemistry (Chapter 1) and littoral benthic invertebrates (Chapter 2) to variation in peak flooding, in addition to examining patterns of metacommunity structure across lakes with differing connectivity to the river (Chapter 3). Using a five-year time series that captured recent extremes in peak flood level, I found that connection time was a dominant factor influencing lake water chemistry because of direct flooding inputs and the effects of spring flooding that carried forward through the growing season. The response of lake chemistry to differing annual peak flood levels differed according to the flooding regime of the lakes. Benthic invertebrate communities sampled over five years in the East Channel were also significantly related to connection time and several of the identified water chemistry variables, indicating that they are sensitive to alterations to flooding hydrology. Analyzing the metacommunity and functional structure of macroinvertebrate communities suggested that the hydrological diversity of lakes contributes to the regional diversity, with aquatic dispersers more limited by dispersal ... Thesis Arctic Arctic Ocean Climate change Inuvialuit Mackenzie Delta Mackenzie river York University, Toronto: YorkSpace Arctic Arctic Ocean Mackenzie Delta ENVELOPE(-136.672,-136.672,68.833,68.833) Mackenzie River |
institution |
Open Polar |
collection |
York University, Toronto: YorkSpace |
op_collection_id |
ftyorkuniv |
language |
English |
topic |
Wildlife conservation Arctic Mackenzie Delta Benthos Benthic macroinvertebrates Biomonitoring Metacommunities Climate change |
spellingShingle |
Wildlife conservation Arctic Mackenzie Delta Benthos Benthic macroinvertebrates Biomonitoring Metacommunities Climate change Scott, Ryan William The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta |
topic_facet |
Wildlife conservation Arctic Mackenzie Delta Benthos Benthic macroinvertebrates Biomonitoring Metacommunities Climate change |
description |
The Mackenzie River Delta is a major outlet to the Arctic Ocean, an important habitat for freshwater organisms, migratory birds, and mammals, and a critical economic and social resource for the Gwich'in and Inuvialuit people. The Delta is also sensitive to climate change, with an increased likelihood of more variable discharge and rising sea levels, leading to forecasts of increasing isolation of many high-elevation floodplain lakes and increasing connectivity of low-elevation lakes. While extensive and ongoing studies of the biogeochemistry of these lakes exist, lower secondary producers such as macroinvertebrates represent an overlooked element of the Mackenzie Delta ecosystem. The objective of this thesis is to identify the effects of flooding on the limnology and benthic invertebrate ecology of this climate-sensitive Arctic region. This thesis addresses this knowledge gap by examining responses of lake water chemistry (Chapter 1) and littoral benthic invertebrates (Chapter 2) to variation in peak flooding, in addition to examining patterns of metacommunity structure across lakes with differing connectivity to the river (Chapter 3). Using a five-year time series that captured recent extremes in peak flood level, I found that connection time was a dominant factor influencing lake water chemistry because of direct flooding inputs and the effects of spring flooding that carried forward through the growing season. The response of lake chemistry to differing annual peak flood levels differed according to the flooding regime of the lakes. Benthic invertebrate communities sampled over five years in the East Channel were also significantly related to connection time and several of the identified water chemistry variables, indicating that they are sensitive to alterations to flooding hydrology. Analyzing the metacommunity and functional structure of macroinvertebrate communities suggested that the hydrological diversity of lakes contributes to the regional diversity, with aquatic dispersers more limited by dispersal ... |
author2 |
Sharma, Sapna |
format |
Thesis |
author |
Scott, Ryan William |
author_facet |
Scott, Ryan William |
author_sort |
Scott, Ryan William |
title |
The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta |
title_short |
The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta |
title_full |
The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta |
title_fullStr |
The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta |
title_full_unstemmed |
The Ecological Response of Lakes and Littoral Benthic Macroinvertebrates to Alterations in Flood Regime in a Climate-Sensitive Arctic River Delta |
title_sort |
ecological response of lakes and littoral benthic macroinvertebrates to alterations in flood regime in a climate-sensitive arctic river delta |
publishDate |
2022 |
url |
http://hdl.handle.net/10315/39053 |
long_lat |
ENVELOPE(-136.672,-136.672,68.833,68.833) |
geographic |
Arctic Arctic Ocean Mackenzie Delta Mackenzie River |
geographic_facet |
Arctic Arctic Ocean Mackenzie Delta Mackenzie River |
genre |
Arctic Arctic Ocean Climate change Inuvialuit Mackenzie Delta Mackenzie river |
genre_facet |
Arctic Arctic Ocean Climate change Inuvialuit Mackenzie Delta Mackenzie river |
op_relation |
http://hdl.handle.net/10315/39053 |
op_rights |
Author owns copyright, except where explicitly noted. Please contact the author directly with licensing requests. |
_version_ |
1766324602534887424 |