Skip to main content

Andrew L Macumber

Queen's University Belfast, School of Natural and Built Environment, Post-Doc

Followers

12

Following

10

Co-authors

9

Public Views

I am currently researching biodiversity of lake Arcellinida. I am studying morphological variability of Arcellinida tests on both spatial and temporal scales and relating that to environmental variability. Key taxa will undergo molecular analysis to confirm whether they represent distinct species.

I am interested in lakes as archives of climate and human land use. I employ Arcellinida (benthic protists) to track in-lake changes in nutrient status, oxygen levels and human contaminants. I employ grain-size analysis to track catchment hydrology. I model whole lake system change using both multivariate ecological statistics and time series analysis.
Phone: 02890973478
Address: School of Natural and Built Environments
Queen's University Belfast
University Road
Belfast
BT7 1NN
Northern Ireland, United Kingdom

less

Interests

Uploads

Paleoclimate of the subarctic treeline by Andrew L Macumber

Paleoclimatological assessment of the Northwest Territories and Implications for the long-term viability of the Tibbitt to Contwoyto Winter Road, Part II: March 2010 Field Season Results

by Andrew L Macumber and Hendrik Falck

High resolution paleoclimatic reconstruction of the last deglaciation in the intertropical Cariaco basin (Venezuela)

The aim of this study is a high-resolution reconstruction of the paleoclimate record of the last ... more The aim of this study is a high-resolution reconstruction of the paleoclimate record of the last 16 ka of the Cariaco Basin, using a combination of geochemical and grain-size analyses. The studied core was collected at the ODP site 1002 on the western edge of the central saddle of the basin (off Venezuela). An age model was determined using a correlation between the magnetic susceptibility record and the planktonic foraminifera delta18O record by Peterson et al. (2000) and a 14C AMS dating. Organic carbon, and carbonate contents and grain-size records show a strong correlation with the delta18O record of the Greenland ice cores (GISP) suggesting that the rapid climatic oscillations of the last deglaciation are simultaneous in the inter-tropical zone and the Northern Hemisphere. In fact, a rapid increase in organic carbon content in marine sediments dated approximately 15 ka could be directly connected with melt-water pulse IA. The relative sea-level rise increased the communication between the Cariaco Basin and the open sea with a strong upwelling enhancing the nutrients supply. The end of the Pleistocene is marked by rapid variation of the organic carbon content in relation with cold events. It seems that in the Cariaco Basin that is directly under the influence of the intertropical convergence, there has been an excellent connection between the Northern Hemisphere and the tropics during the last deglaciation. In contrast, it is noteworthy that the 8.2 ka events is not recorded in this area probably because the connection was not complete with a diversion of meltwater from the Mississippi to the Saint Lawrence drainage system during the Younger Dryas. Peterson L.C., et al. (2000) Proceedings of the ODP, Sci. Res., 165, 85-99.

NWT Open Report 2010-002

Influence of Pacific decadal oscillation and El Niño Southern oscillation on the summer monsoon precipitation in Myanmar

International Journal of Climatology, 2011

Middle to late Holocene chironomid-inferred July temperatures for the central Northwest Territories, Canada

by Andrew L Macumber and Michael Pisaric

Journal of Paleolimnology, 2014

Sediment accumulation rates in subarctic lakes: insights into age-depth modeling from 22 dated lake records from the Northwest Territories, Canada

Quaternary Geochronology, 2015

ABSTRACT Age-depth modeling using Bayesian statistics requires well-informed prior information ab... more ABSTRACT Age-depth modeling using Bayesian statistics requires well-informed prior information about the behavior of sediment accumulation. Here we present average sediment accumulation rates (represented as deposition times, DT, in yr/cm) for lakes in an Arctic setting, and we examine the variability across space (intra- and inter-lake) and time (late Holocene). The dataset includes over 100 radiocarbon dates, primarily on bulk sediment, from 22 sediment cores obtained from 18 lakes spanning the boreal to tundra ecotone gradients in subarctic Canada. There are four to twenty-five radiocarbon dates per core, depending on the length and character of the sediment records. Deposition times were calculated at 100-year intervals from age-depth models constructed using the ‘classical’ age-depth modeling software Clam. Lakes in boreal settings have the most rapid accumulation (mean DT 20 ± 10 years), whereas lakes in tundra settings accumulate at moderate (mean DT 70 ± 10 years) to very slow rates, (&gt;100 yr/cm). Many of the age-depth models demonstrate fluctuations in accumulation that coincide with lake evolution and post-glacial climate change. Ten of our sediment cores yielded sediments as old as c. 9,000 cal BP (BP = years before AD 1950). From between c. 9,000 cal BP and c. 6,000 cal BP, sediment accumulation was relatively rapid (DT of 20 to 60 yr/cm). Accumulation slowed between c. 5,500 and c. 4,000 cal BP as vegetation expanded northward in response to warming. A short period of rapid accumulation occurred near 1,200 cal BP at three lakes. Our research will help inform priors in Bayesian age modeling.

Radiocarbon dating and Bayesian age-depth modeling in the Canadian subarctic (Tibbitt to Contwoyto Winter Road Project)

Palynological analysis of Danny's Lake, Central Northwest Territories

Neoglacial Climate Variability in Diatom Populations from the sub-Arctic

by Andrew L Macumber and April Dalton

Spatial and temporal variability in lake accumulation rates in subarctic Canada: Implications for Bayesian age-depth modeling

by Andrew L Macumber and Hendrik Falck

A reconstruction of climate history at high resolution using C and N isotopes, Northwest Territories, Canada

by Andrew L Macumber and April Dalton

An assessment of Arsenic and heavy metal contamination and paleoclimatic change in Pocket Lake, Baker Creek Watershed, Northwest Territories, Canada

by Andrew L Macumber and Hendrik Falck

Diatoms as indicators of decadal to centennial-scale climate cyclicity and winterice cover in the treeline regions of the central Northwest Territories, Canada

by Andrew L Macumber and April Dalton

Temporal environmental proxies for assessing 'problem' lakes along the Tibbitt to Contwoyto Winter Road

by Andrew L Macumber and Hendrik Falck

The diamond industry is an essential component of the economy of the Northwest Territories (NT) a... more The diamond industry is an essential component of the economy of the Northwest Territories (NT) and the Tibbitt to Contwoyto Winter Road (TCWR) is the sole infrastructure for the transportation of goods and services to and from mines and other projects north of Yellowknife. Reliable methods for lake selection are critical to the viability of the road because 87% of the TCWR’s ~600 km length is across frozen lakes. Changing ice stability and thickness thus dramatically impacts the use of the road. Two ‘problem’ lakes (P26 and P33) found on the route of the TCWR typically take longer to freeze in early winter and are the first lakes to thaw in the spring as they are not only characterized by thinner ice but by high levels of gas. Gas buildup under the ice can be dangerous for users of the road as it can result in blowouts, which results when gas bubbles break through the ice surface. To better understand the limnological character of P26 and P33 they were analyzed for microscopic bioi...

Late Holocene palynological investigation of Waite Lake, central Northwest Territories

by Andrew L Macumber and Hendrik Falck

Natural resource developments are an essential component of the economy of the Northwest Territor... more Natural resource developments are an essential component of the economy of the Northwest Territories (NT), accounting for over 50% of the territorial real domestic product. Transportation of goods and services to and from mines and projects in the NT represents a major challenge due to a lack of infrastructure in Canada’s territories and the remoteness of many industrial properties. A 568 km long winter road, called the Tibbitt to Contwoyto Winter Road (TCWR), is the only ground transportation route that services mines in the NT, including the Ekati Diamond Mine (BHP Billiton Inc.) and the Diavik Diamond Mine (Rio Tinto Group) and is thus the critical link in the supply chain. Cold winter temperatures are necessary for the continued viability of the TCWR as most of the road (495 km; 87%) is built over frozen lakes. Changing ice stability, thickness, and duration of cover associated with recent climate variability have impacted the use of the road. The purpose of our project is to an...

Paleoclimatological assessment of the central Northwest Territories, Canada: Implications for the long-term viability of the Tibbett to Contwoyto Winter Ice Road. Session 19: Biotic proxies in lake sediments as quantitative indicators of of Quaternary environmental change: development, calibratio...

High resolution multiproxy study of lacustrine sediments from Waite Lake, Tibbitt to Contwoyto Winter Road, NT

by Andrew L Macumber and Hendrik Falck

Late Holocene cyclical patterns of diatom populations in sub-boreal Northwest Territories

by Andrew L Macumber and April Dalton

7,500-year record of Canadian Subarctic climate dynamics as evidenced by fossil Arcellacea, isotopic signatures and sediment particle size

by Andrew L Macumber and Hendrik Falck

Climate Phenomena and Episodes Recorded in the Sediment Record from a Sub-Arctic Lake

by Andrew L Macumber and April Dalton

Paleoclimatological assessment of the Northwest Territories and Implications for the long-term viability of the Tibbitt to Contwoyto Winter Road, Part II: March 2010 Field Season Results

by Andrew L Macumber and Hendrik Falck

High resolution paleoclimatic reconstruction of the last deglaciation in the intertropical Cariaco basin (Venezuela)

The aim of this study is a high-resolution reconstruction of the paleoclimate record of the last ... more The aim of this study is a high-resolution reconstruction of the paleoclimate record of the last 16 ka of the Cariaco Basin, using a combination of geochemical and grain-size analyses. The studied core was collected at the ODP site 1002 on the western edge of the central saddle of the basin (off Venezuela). An age model was determined using a correlation between the magnetic susceptibility record and the planktonic foraminifera delta18O record by Peterson et al. (2000) and a 14C AMS dating. Organic carbon, and carbonate contents and grain-size records show a strong correlation with the delta18O record of the Greenland ice cores (GISP) suggesting that the rapid climatic oscillations of the last deglaciation are simultaneous in the inter-tropical zone and the Northern Hemisphere. In fact, a rapid increase in organic carbon content in marine sediments dated approximately 15 ka could be directly connected with melt-water pulse IA. The relative sea-level rise increased the communication between the Cariaco Basin and the open sea with a strong upwelling enhancing the nutrients supply. The end of the Pleistocene is marked by rapid variation of the organic carbon content in relation with cold events. It seems that in the Cariaco Basin that is directly under the influence of the intertropical convergence, there has been an excellent connection between the Northern Hemisphere and the tropics during the last deglaciation. In contrast, it is noteworthy that the 8.2 ka events is not recorded in this area probably because the connection was not complete with a diversion of meltwater from the Mississippi to the Saint Lawrence drainage system during the Younger Dryas. Peterson L.C., et al. (2000) Proceedings of the ODP, Sci. Res., 165, 85-99.

NWT Open Report 2010-002

Influence of Pacific decadal oscillation and El Niño Southern oscillation on the summer monsoon precipitation in Myanmar

International Journal of Climatology, 2011

Middle to late Holocene chironomid-inferred July temperatures for the central Northwest Territories, Canada

by Andrew L Macumber and Michael Pisaric

Journal of Paleolimnology, 2014

Sediment accumulation rates in subarctic lakes: insights into age-depth modeling from 22 dated lake records from the Northwest Territories, Canada

Quaternary Geochronology, 2015

ABSTRACT Age-depth modeling using Bayesian statistics requires well-informed prior information ab... more ABSTRACT Age-depth modeling using Bayesian statistics requires well-informed prior information about the behavior of sediment accumulation. Here we present average sediment accumulation rates (represented as deposition times, DT, in yr/cm) for lakes in an Arctic setting, and we examine the variability across space (intra- and inter-lake) and time (late Holocene). The dataset includes over 100 radiocarbon dates, primarily on bulk sediment, from 22 sediment cores obtained from 18 lakes spanning the boreal to tundra ecotone gradients in subarctic Canada. There are four to twenty-five radiocarbon dates per core, depending on the length and character of the sediment records. Deposition times were calculated at 100-year intervals from age-depth models constructed using the ‘classical’ age-depth modeling software Clam. Lakes in boreal settings have the most rapid accumulation (mean DT 20 ± 10 years), whereas lakes in tundra settings accumulate at moderate (mean DT 70 ± 10 years) to very slow rates, (&gt;100 yr/cm). Many of the age-depth models demonstrate fluctuations in accumulation that coincide with lake evolution and post-glacial climate change. Ten of our sediment cores yielded sediments as old as c. 9,000 cal BP (BP = years before AD 1950). From between c. 9,000 cal BP and c. 6,000 cal BP, sediment accumulation was relatively rapid (DT of 20 to 60 yr/cm). Accumulation slowed between c. 5,500 and c. 4,000 cal BP as vegetation expanded northward in response to warming. A short period of rapid accumulation occurred near 1,200 cal BP at three lakes. Our research will help inform priors in Bayesian age modeling.

Radiocarbon dating and Bayesian age-depth modeling in the Canadian subarctic (Tibbitt to Contwoyto Winter Road Project)

Palynological analysis of Danny's Lake, Central Northwest Territories

Neoglacial Climate Variability in Diatom Populations from the sub-Arctic

by Andrew L Macumber and April Dalton

Spatial and temporal variability in lake accumulation rates in subarctic Canada: Implications for Bayesian age-depth modeling

by Andrew L Macumber and Hendrik Falck

A reconstruction of climate history at high resolution using C and N isotopes, Northwest Territories, Canada

by Andrew L Macumber and April Dalton

An assessment of Arsenic and heavy metal contamination and paleoclimatic change in Pocket Lake, Baker Creek Watershed, Northwest Territories, Canada

by Andrew L Macumber and Hendrik Falck

Diatoms as indicators of decadal to centennial-scale climate cyclicity and winterice cover in the treeline regions of the central Northwest Territories, Canada

by Andrew L Macumber and April Dalton

Temporal environmental proxies for assessing 'problem' lakes along the Tibbitt to Contwoyto Winter Road

by Andrew L Macumber and Hendrik Falck

The diamond industry is an essential component of the economy of the Northwest Territories (NT) a... more The diamond industry is an essential component of the economy of the Northwest Territories (NT) and the Tibbitt to Contwoyto Winter Road (TCWR) is the sole infrastructure for the transportation of goods and services to and from mines and other projects north of Yellowknife. Reliable methods for lake selection are critical to the viability of the road because 87% of the TCWR’s ~600 km length is across frozen lakes. Changing ice stability and thickness thus dramatically impacts the use of the road. Two ‘problem’ lakes (P26 and P33) found on the route of the TCWR typically take longer to freeze in early winter and are the first lakes to thaw in the spring as they are not only characterized by thinner ice but by high levels of gas. Gas buildup under the ice can be dangerous for users of the road as it can result in blowouts, which results when gas bubbles break through the ice surface. To better understand the limnological character of P26 and P33 they were analyzed for microscopic bioi...

Late Holocene palynological investigation of Waite Lake, central Northwest Territories

by Andrew L Macumber and Hendrik Falck

Natural resource developments are an essential component of the economy of the Northwest Territor... more Natural resource developments are an essential component of the economy of the Northwest Territories (NT), accounting for over 50% of the territorial real domestic product. Transportation of goods and services to and from mines and projects in the NT represents a major challenge due to a lack of infrastructure in Canada’s territories and the remoteness of many industrial properties. A 568 km long winter road, called the Tibbitt to Contwoyto Winter Road (TCWR), is the only ground transportation route that services mines in the NT, including the Ekati Diamond Mine (BHP Billiton Inc.) and the Diavik Diamond Mine (Rio Tinto Group) and is thus the critical link in the supply chain. Cold winter temperatures are necessary for the continued viability of the TCWR as most of the road (495 km; 87%) is built over frozen lakes. Changing ice stability, thickness, and duration of cover associated with recent climate variability have impacted the use of the road. The purpose of our project is to an...

Paleoclimatological assessment of the central Northwest Territories, Canada: Implications for the long-term viability of the Tibbett to Contwoyto Winter Ice Road. Session 19: Biotic proxies in lake sediments as quantitative indicators of of Quaternary environmental change: development, calibratio...

High resolution multiproxy study of lacustrine sediments from Waite Lake, Tibbitt to Contwoyto Winter Road, NT

by Andrew L Macumber and Hendrik Falck

Late Holocene cyclical patterns of diatom populations in sub-boreal Northwest Territories

by Andrew L Macumber and April Dalton

7,500-year record of Canadian Subarctic climate dynamics as evidenced by fossil Arcellacea, isotopic signatures and sediment particle size

by Andrew L Macumber and Hendrik Falck

Climate Phenomena and Episodes Recorded in the Sediment Record from a Sub-Arctic Lake

by Andrew L Macumber and April Dalton

Arcellacea (Testate Lobose Amoebae) as pH Indicators in a Pyrite Mine-Acidified Lake, Northeastern Ontario, Canada

Microbial Ecology, 2013

Autoecological Approaches to Resolve Subjective Taxonomic Divisions within Arcellacea

Protist, 2014

Relationship between ecological indicators (Arcellacea), total mercury concentrations and grain size in lakes within the Athabasca oil sands region, Alberta

Environmental Earth Sciences, 2013

Arcellaceans (testate lobose amoebae) as an aquatic ecosystem bio-indicator to gauge the potential environmental impact of oil sands operations, specifically mercury in the Fort McMurray region, Alberta, Canada

Use of an aquatic ecosystem bio-indicator to gauge environmental impact and efficiency of remediation efforts in oil sands tailings ponds and lakes surrounding Fort McMurray, Alberta

by Andrew L Macumber and Francine McCarthy

Response of benthic microorganisms (thecamoebians) to oil sands process-affected materials; providing endpoints for gauging aquatic reclamation success

by Andrew L Macumber and Francine McCarthy

Constructed wetlands and end-pit lakes will play an important role in reclamation options for flu... more Constructed wetlands and end-pit lakes will play an important role in reclamation options for fluid tailings (OSPW/M) at surface oil sands operations. Through time and with natural bioremediation viable aquatic habitats will develop, but currently few tools are available to determine the rates of remediation in produced ecosystems. A micropaleoecological environmental proxy (thecamoebians) has been demonstrated to provide a time-averaged indicator of ecosystem health. Thecamoebian communities in sediments from both impacted and non-impacted wetlands and lakes in the vicinity of oil sands operation have been compared. An index of response to stress has been compiled with the goal of using it as a predictor of the path of remediation that will produce sustainable ecosystems. This information also provides an endpoint for remediation efforts. Thecamoebian assemblages in cores and surface samples from 63 natural lakes across the region were used to establish natural ecological ranges an...

Arcellaceans (Testate Lobose Amoebae) as Proxies for Arsenic and Heavy Metal Contamination in the Baker Creek Watershed, Northwest Territories, Canada

by Andrew L Macumber and Hendrik Falck

Arcellacea as proxies of ocean-atmosphere influenced hydroecologic cycles in a northern Alberta, Canada lake

Responses of benthic microorganisms (thecamoebians) to Oil Sands Process-affected materials provide endpoints for gauging aquatic reclamation success

by Andrew L Macumber and Francine McCarthy

Utility of arcellaceans (shelled protists) as a tool for monitoring arsenic and heavy metal contamination

Heavy metal contamination has been noted as an issue of concern in lakes and streams throughout t... more Heavy metal contamination has been noted as an issue of concern in lakes and streams throughout the Great Toronto Area (GTA), as well as many other areas of Canada. Air dispersal of Arsenic (As) and other metals (e.g. Al, Cd, Cu, Hg) derived from smelting of gold bearing ore is a major environmental issue in the Yellowknife, NT area. Before the installation of efficient scrubbers in the 1950s as much as 10,000 kg of Arsenic trioxide (As203) was released into the atmosphere per day, resulting in considerable ecological damage. To test arcellacean (well preserved shelled protists) efficacy as bioindicators we carried out Detrended Correspondence Analysis (DCA) and Redundancy Analysis (RDA) on the spatial distribution of arcellaceans, water property data and ICP-MS metal analysis results from 61 Yellowknife area lakes. Results indicate that in the Yellowknife area As concentration in lake substrates has the greatest influence on arcellacean distribution (10.7% of variance). Stress-indi...

A sledge microtome for high resolution subsampling of freeze cores

by Andrew L Macumber and Hendrik Falck

Journal of Paleolimnology, 2011