cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.1011902
title: Sequencing depth and diversity and dominance indices for the selected samples of cryoconite from Aldegondabreen

description: <b>Table 5.</b> Sequencing depth and diversity and dominance indices for the selected samples of cryoconite from Aldegondabreen. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011902.v1
title: Sequencing depth and diversity and dominance indices for the selected samples of cryoconite from Aldegondabreen

description: <b>Table 5.</b> Sequencing depth and diversity and dominance indices for the selected samples of cryoconite from Aldegondabreen. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011900
title: Nutrient concentrations in cryoconite sediment, supraglacial meltwater, and surface ice on Aldegondabreen

description: <b>Table 3.</b> Nutrient concentrations in cryoconite sediment, supraglacial meltwater, and surface ice on Aldegondabreen. TC (total carbon), TN (total nitrogen), TP (total phosphorus) in mg g<sup>−1</sup> (mean ± sd, <em>n</em> = 3); DOC (dissolved organic carbon) in mg l<sup>−1</sup>, TDN (total dissolved nitrogen), NO<sub>3</sub><sup>−</sup>, NH<sub>4</sub><sup>+</sup> in μg l<sup>−1</sup>. b.d. below detection limit; n.d. not determined. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011901
title: Abundances of the 16S rRNA gene and bacterial and archaeal <em>amoA</em> genes (gene copies g<sup>−1</sup>) in cryoconite on Aldegondabreen (mean ± sd; <em>n</em> = 3)

description: <b>Table 4.</b> Abundances of the 16S rRNA gene and bacterial and archaeal <em>amoA</em> genes (gene copies g<sup>−1</sup>) in cryoconite on Aldegondabreen (mean ± sd; <em>n</em> = 3). b.d. below detection limit. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011898
title: Primer sets used for qPCR of 16S rRNA and <em>amoA</em> genes from the cryoconite samples

description: <b>Table 1.</b> Primer sets used for qPCR of 16S rRNA and <em>amoA</em> genes from the cryoconite samples. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011899
title: Geographical parameters of the sampling sites on Aldegondabreen

description: <b>Table 2.</b> Geographical parameters of the sampling sites on Aldegondabreen. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011900.v1
title: Nutrient concentrations in cryoconite sediment, supraglacial meltwater, and surface ice on Aldegondabreen

description: <b>Table 3.</b> Nutrient concentrations in cryoconite sediment, supraglacial meltwater, and surface ice on Aldegondabreen. TC (total carbon), TN (total nitrogen), TP (total phosphorus) in mg g<sup>−1</sup> (mean ± sd, <em>n</em> = 3); DOC (dissolved organic carbon) in mg l<sup>−1</sup>, TDN (total dissolved nitrogen), NO<sub>3</sub><sup>−</sup>, NH<sub>4</sub><sup>+</sup> in μg l<sup>−1</sup>. b.d. below detection limit; n.d. not determined. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011901.v1
title: Abundances of the 16S rRNA gene and bacterial and archaeal <em>amoA</em> genes (gene copies g<sup>−1</sup>) in cryoconite on Aldegondabreen (mean ± sd; <em>n</em> = 3)

description: <b>Table 4.</b> Abundances of the 16S rRNA gene and bacterial and archaeal <em>amoA</em> genes (gene copies g<sup>−1</sup>) in cryoconite on Aldegondabreen (mean ± sd; <em>n</em> = 3). b.d. below detection limit. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011898.v1
title: Primer sets used for qPCR of 16S rRNA and <em>amoA</em> genes from the cryoconite samples

description: <b>Table 1.</b> Primer sets used for qPCR of 16S rRNA and <em>amoA</em> genes from the cryoconite samples. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011899.v1
title: Geographical parameters of the sampling sites on Aldegondabreen

description: <b>Table 2.</b> Geographical parameters of the sampling sites on Aldegondabreen. <strong>Abstract</strong> The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and <em>amoA</em> genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.
DOI: 10.6084/m9.figshare.1011888
title: Photosynthetic and bacterial production rates of 20 study ponds

description: <b>Table 2.</b> Photosynthetic and bacterial production rates of 20 study ponds. Mean values (<em>n</em> = 4) with SD in brackets. <strong>Abstract</strong> We compared planktonic primary and secondary production across twenty meltwater ponds on the surface of the McMurdo Ice Shelf in January 2007, including some ponds with basal brines created by meromictic stratification. Primary production ranged from 1.07 to 65.72 mgC m<sup>−3</sup> h<sup>−1</sup> in surface waters. In stratified ponds primary production was always more than ten times higher in basal brines than in the corresponding mixolimnion. Regression tree analysis (<em>r</em><sup>2</sup> = 0.80) identified inorganic nitrogen (as {\mathrm{NH}}_{4}^{+}) as the main factor limiting planktonic primary production. However, there was also evidence of inorganic carbon co-limitation of photosynthesis in some of the more oligotrophic waters. Neither C nor N limited carbon fixation at [NH<sub>4</sub>–N] &gt; 50 mg m<sup>−3</sup>, with photoinhibition the factor most likely limiting photosynthesis under such conditions. Primary production was the only factor significantly correlated to bacterial production and the relationship (<em>r</em><sup>2</sup> = 0.56) was non-linear. Nitrogen limitation and tight coupling of planktonic primary and bacterial production is surprising in these ponds, as all have large pools of dissolved organic carbon (1.2–260 g m<sup>−3</sup>) and organic nitrogen (all &gt;130 mg m<sup>−3</sup>). The dissolved pools of organic carbon and nitrogen appear to be recalcitrant and bacterial production to be constrained by limited release of labile organics from phytoplankton.
DOI: 10.6084/m9.figshare.1011889
title: Pearson correlation coefficients of log-transformed data for all variables

description: <b>Table 3.</b> Pearson correlation coefficients of log-transformed data for all variables. Correlations &gt;0.55 and significant at <em>P</em> <strong>Abstract</strong> We compared planktonic primary and secondary production across twenty meltwater ponds on the surface of the McMurdo Ice Shelf in January 2007, including some ponds with basal brines created by meromictic stratification. Primary production ranged from 1.07 to 65.72 mgC m<sup>−3</sup> h<sup>−1</sup> in surface waters. In stratified ponds primary production was always more than ten times higher in basal brines than in the corresponding mixolimnion. Regression tree analysis (<em>r</em><sup>2</sup> = 0.80) identified inorganic nitrogen (as {\mathrm{NH}}_{4}^{+}) as the main factor limiting planktonic primary production. However, there was also evidence of inorganic carbon co-limitation of photosynthesis in some of the more oligotrophic waters. Neither C nor N limited carbon fixation at [NH<sub>4</sub>–N] &gt; 50 mg m<sup>−3</sup>, with photoinhibition the factor most likely limiting photosynthesis under such conditions. Primary production was the only factor significantly correlated to bacterial production and the relationship (<em>r</em><sup>2</sup> = 0.56) was non-linear. Nitrogen limitation and tight coupling of planktonic primary and bacterial production is surprising in these ponds, as all have large pools of dissolved organic carbon (1.2–260 g m<sup>−3</sup>) and organic nitrogen (all &gt;130 mg m<sup>−3</sup>). The dissolved pools of organic carbon and nitrogen appear to be recalcitrant and bacterial production to be constrained by limited release of labile organics from phytoplankton.
DOI: 10.6084/m9.figshare.1011891
title: Regression tree threshold values, uncertainty estimates, and <em>P</em>-values for phytoplankton production and bacterial production

description: <b>Table 5.</b> Regression tree threshold values, uncertainty estimates, and <em>P</em>-values for phytoplankton production and bacterial production. <strong>Abstract</strong> We compared planktonic primary and secondary production across twenty meltwater ponds on the surface of the McMurdo Ice Shelf in January 2007, including some ponds with basal brines created by meromictic stratification. Primary production ranged from 1.07 to 65.72 mgC m<sup>−3</sup> h<sup>−1</sup> in surface waters. In stratified ponds primary production was always more than ten times higher in basal brines than in the corresponding mixolimnion. Regression tree analysis (<em>r</em><sup>2</sup> = 0.80) identified inorganic nitrogen (as {\mathrm{NH}}_{4}^{+}) as the main factor limiting planktonic primary production. However, there was also evidence of inorganic carbon co-limitation of photosynthesis in some of the more oligotrophic waters. Neither C nor N limited carbon fixation at [NH<sub>4</sub>–N] &gt; 50 mg m<sup>−3</sup>, with photoinhibition the factor most likely limiting photosynthesis under such conditions. Primary production was the only factor significantly correlated to bacterial production and the relationship (<em>r</em><sup>2</sup> = 0.56) was non-linear. Nitrogen limitation and tight coupling of planktonic primary and bacterial production is surprising in these ponds, as all have large pools of dissolved organic carbon (1.2–260 g m<sup>−3</sup>) and organic nitrogen (all &gt;130 mg m<sup>−3</sup>). The dissolved pools of organic carbon and nitrogen appear to be recalcitrant and bacterial production to be constrained by limited release of labile organics from phytoplankton.