cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14332951.v1
title: Soft rocks, hard rocks: the world’s resources and reserves of Ti and Zr and associated critical minerals

description: Titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), garnet, and rare earth elements (REO) and their associated minerals are essential for modern society. Despite this, comprehensive public understanding of Ti and Zr resources and reserves (including garnet, Hf contained in zircon, V in titanomagnetite, and REO contained in co/by-product monazite) has been limited.This has led to uncertainty over the possibility of supply shortages in these minerals and has also led to confusion over which Ti and Zr minerals may be in short supply. Addressing this, we compile an extensive database of the world’s known Ti and Zr mineral deposits including ore grades, co-products, mineral quality, and geological settings. Our data indicate that 327 mineral deposits in 25 countries contain a collective 2,648 Mt TiO<sub>2</sub> in ilmenite, rutile and leucoxene, 155 Mt of Zr minerals, 23.5 Mt of V, 16.2 Mt of REO and 17.5 Mt of garnet. Just 31% of TiO<sub>2</sub> exists within traditional sedimentary deposits (placer and palaeo-placer deposits, but here referred to as sedimentary), with the remainder contained within igneous (54%), metamorphic (1%), and laterite deposits (14%). For igneous TiO<sub>2</sub>, 58% is contained within ilmenite, 42% in titanomagnetite, and &lt;1% in rutile. 93% of total zirconium minerals are contained in sedimentary deposits. Forward modelling presented in this paper indicates that Ti and Zr resources and reserves are sufficient to meet global demand for several decades. Overall, this unique study presents extensive data on Zr, Ti, Hf, V, garnet and REO resources, makes comments on the future availability of these elements and will therefore be a practical resource for researchers, policymakers, and investors alike.
DOI: 10.6084/m9.figshare.12999547
title: Modern foraminiferal assemblages in northern Nares Strait, Petermann Fjord, and beneath Petermann ice tongue, NW Greenland

description: Calving events of Petermann Glacier, northwest Greenland, in 2010 and 2012 reduced the length of its ice tongue by c. 25 km, allowing exploration of newly uncovered seafloor during the Petermann 2015 Expedition. This article presents the results of foraminiferal analysis and environmental data from thirteen surface sediment samples in northern Nares Strait and Petermann Fjord, including beneath the modern ice tongue. This is the first study of living foraminifera beneath an arctic ice tongue and the first modern foraminiferal data from this area. Modern assemblages were studied to constrain species environmental preferences and to improve paleoenvironmental interpretations of foraminiferal assemblages. Sub–ice tongue assemblages differed greatly from those at all other sites, with very low faunal abundances and being dominated by agglutinated fauna, likely reflecting low food supply under the ice tongue. Fjord fauna were comprised of 80 percent or more calcareous species. Notably, <i>Elphidium clavatum</i> is absent beneath the ice tongue although it is dominant in the fjord. Increasing primary productivity associated with the transition to mobile sea ice, diminishing influence of the Petermann Glacier meltwater with distance from the grounding line, and increased influence of south-flowing currents in Nares Strait are the important controls on the faunal assemblages.
DOI: 10.6084/m9.figshare.12999547.v1
title: Modern foraminiferal assemblages in northern Nares Strait, Petermann Fjord, and beneath Petermann ice tongue, NW Greenland

description: Calving events of Petermann Glacier, northwest Greenland, in 2010 and 2012 reduced the length of its ice tongue by c. 25 km, allowing exploration of newly uncovered seafloor during the Petermann 2015 Expedition. This article presents the results of foraminiferal analysis and environmental data from thirteen surface sediment samples in northern Nares Strait and Petermann Fjord, including beneath the modern ice tongue. This is the first study of living foraminifera beneath an arctic ice tongue and the first modern foraminiferal data from this area. Modern assemblages were studied to constrain species environmental preferences and to improve paleoenvironmental interpretations of foraminiferal assemblages. Sub–ice tongue assemblages differed greatly from those at all other sites, with very low faunal abundances and being dominated by agglutinated fauna, likely reflecting low food supply under the ice tongue. Fjord fauna were comprised of 80 percent or more calcareous species. Notably, <i>Elphidium clavatum</i> is absent beneath the ice tongue although it is dominant in the fjord. Increasing primary productivity associated with the transition to mobile sea ice, diminishing influence of the Petermann Glacier meltwater with distance from the grounding line, and increased influence of south-flowing currents in Nares Strait are the important controls on the faunal assemblages.
DOI: 10.6084/m9.figshare.11605551.v1
title: Ground surface temperature variability and permafrost distribution over mountainous terrain in northern Mongolia

description: Permafrost plays an important role in numerous environmental processes at high latitudes and in high mountain areas. The identification of mountain permafrost, particularly in the discontinuous permafrost regions, is challenging due to limited data availability and the high spatial variability of controlling factors. This study focuses on mountain permafrost in a data-scarce environment of northern Mongolia, at the interface between the boreal forest and the dry steppe mid-latitudes. In this region, the ground temperature has been increasing continuously since 2011 and has a high spatial variability due to the distribution of incoming solar radiation, as well as seasonal snow and vegetation cover. We analyzed the effect of these controlling factors to understand the climate–permafrost relationship based on in situ observations. Furthermore, mean ground surface temperature (MGST) was calculated at 30-m resolution to predict permafrost distribution. The calculated MGST, with a root mean square error of ±1.4°C, shows permafrost occurrence on north-facing slopes and at higher elevations and absence on south-facing slopes. Borehole temperature data indicate a serious wildfire-induced permafrost degradation in the region; therefore, special attention should be paid to further investigations on ecosystem resilience and climate change mitigation in this region.
DOI: 10.6084/m9.figshare.19448024.v1
title: When parents play favourites: Brood demand shapes parental preference for offspring UV colour

description: Available Datasets of the MS entitled: "When parents play favourites: Brood demand shapes parental preference for offspring UV colour"<br>
DOI: 10.6084/m9.figshare.12851959
title: Timing of Little Ice Age maxima and subsequent glacier retreat in northern Troms and western Finnmark, northern Norway

description: Glaciers are important indicators of climate change, and recent observations worldwide document increasing rates of mountain glacier recession. Here we present approximately 200 years of change in mountain glacier extent in northern Troms and western Finnmark, northern Norway. This was achieved through (1) mapping and lichenometric dating of major moraine systems within a subset of the main study area (the Rotsund Valley) and (2) mapping recent (post-1980s) changes in ice extent from remotely sensed data. Lichenometric dating reveals that the Little Ice Age (LIA) maximum occurred approximately 1814 (±41 years), which is before the early twentieth-century LIA maximum proposed on the nearby Lyngen Peninsula but younger than LIA maximum limits in southern and central Norway (mid-eighteenth century). Between LIA maximum and 1989, a small sample of measured glaciers (<i>n</i> = 15) shrank a total of 3.9 km<sup>2</sup> (39 percent), and those that shrank by more than 50 percent are fronted by proglacial lakes. Between 1989 and 2018, the total area of glaciers within the study area (<i>n</i> = 219 in 1989) shrank by approximately 35 km<sup>2</sup>. Very small glaciers (&lt;0.5 km<sup>2</sup>) show the highest relative rates of shrinkage, and 90 percent of mapped glaciers within the study area were less than 0.5 km<sup>2</sup> in 2018.
DOI: 10.6084/m9.figshare.19448024
title: When parents play favourites: Brood demand shapes parental preference for offspring UV colour

description: Available Datasets of the MS entitled: "When parents play favourites: Brood demand shapes parental preference for offspring UV colour"<br>
DOI: 10.6084/m9.figshare.12851959.v1
title: Timing of Little Ice Age maxima and subsequent glacier retreat in northern Troms and western Finnmark, northern Norway

description: Glaciers are important indicators of climate change, and recent observations worldwide document increasing rates of mountain glacier recession. Here we present approximately 200 years of change in mountain glacier extent in northern Troms and western Finnmark, northern Norway. This was achieved through (1) mapping and lichenometric dating of major moraine systems within a subset of the main study area (the Rotsund Valley) and (2) mapping recent (post-1980s) changes in ice extent from remotely sensed data. Lichenometric dating reveals that the Little Ice Age (LIA) maximum occurred approximately 1814 (±41 years), which is before the early twentieth-century LIA maximum proposed on the nearby Lyngen Peninsula but younger than LIA maximum limits in southern and central Norway (mid-eighteenth century). Between LIA maximum and 1989, a small sample of measured glaciers (<i>n</i> = 15) shrank a total of 3.9 km<sup>2</sup> (39 percent), and those that shrank by more than 50 percent are fronted by proglacial lakes. Between 1989 and 2018, the total area of glaciers within the study area (<i>n</i> = 219 in 1989) shrank by approximately 35 km<sup>2</sup>. Very small glaciers (&lt;0.5 km<sup>2</sup>) show the highest relative rates of shrinkage, and 90 percent of mapped glaciers within the study area were less than 0.5 km<sup>2</sup> in 2018.
DOI: 10.6084/m9.figshare.11605551
title: Ground surface temperature variability and permafrost distribution over mountainous terrain in northern Mongolia

description: Permafrost plays an important role in numerous environmental processes at high latitudes and in high mountain areas. The identification of mountain permafrost, particularly in the discontinuous permafrost regions, is challenging due to limited data availability and the high spatial variability of controlling factors. This study focuses on mountain permafrost in a data-scarce environment of northern Mongolia, at the interface between the boreal forest and the dry steppe mid-latitudes. In this region, the ground temperature has been increasing continuously since 2011 and has a high spatial variability due to the distribution of incoming solar radiation, as well as seasonal snow and vegetation cover. We analyzed the effect of these controlling factors to understand the climate–permafrost relationship based on in situ observations. Furthermore, mean ground surface temperature (MGST) was calculated at 30-m resolution to predict permafrost distribution. The calculated MGST, with a root mean square error of ±1.4°C, shows permafrost occurrence on north-facing slopes and at higher elevations and absence on south-facing slopes. Borehole temperature data indicate a serious wildfire-induced permafrost degradation in the region; therefore, special attention should be paid to further investigations on ecosystem resilience and climate change mitigation in this region.
DOI: 10.6084/m9.figshare.12040080
title: Above- and belowground responses to long-term herbivore exclusion

description: Herbivores can play an important role in determining arctic ecosystem function with effects determined in part by herbivore identity. We examined the impact of long-term (twenty-two years) small and large mammal herbivore exclusion in two arctic plant communities in northern Alaska: dry heath (DH) and moist acidic tundra (MAT). Our aims were to examine how herbivore exclusion influences (1) plant communities and (2) soil nutrient pools and microbial processes. Though herbivore absence increased moss and decreased evergreen shrub cover in MAT, there were few other significant effects on vegetation in either community. We also observed no influence of exclusion on most soil properties. However, in DH, phosphatase activity was greater in areas where small mammals alone were present, suggesting that they are altering phosphorus (P) availability, perhaps through herbivores’ influence on the plant community and subsequently on competition for P with the microbial community. We conclude that herbivore impacts in the Arctic are dependent on both the plant community and herbivore identity (size). We show the importance of understanding the roles of herbivores in the Arctic and contribute to a growing number of herbivore studies in a biome likely to experience future changes in herbivore communities and ecosystem function.
DOI: 10.6084/m9.figshare.12040080.v1
title: Above- and belowground responses to long-term herbivore exclusion

description: Herbivores can play an important role in determining arctic ecosystem function with effects determined in part by herbivore identity. We examined the impact of long-term (twenty-two years) small and large mammal herbivore exclusion in two arctic plant communities in northern Alaska: dry heath (DH) and moist acidic tundra (MAT). Our aims were to examine how herbivore exclusion influences (1) plant communities and (2) soil nutrient pools and microbial processes. Though herbivore absence increased moss and decreased evergreen shrub cover in MAT, there were few other significant effects on vegetation in either community. We also observed no influence of exclusion on most soil properties. However, in DH, phosphatase activity was greater in areas where small mammals alone were present, suggesting that they are altering phosphorus (P) availability, perhaps through herbivores’ influence on the plant community and subsequently on competition for P with the microbial community. We conclude that herbivore impacts in the Arctic are dependent on both the plant community and herbivore identity (size). We show the importance of understanding the roles of herbivores in the Arctic and contribute to a growing number of herbivore studies in a biome likely to experience future changes in herbivore communities and ecosystem function.
DOI: 10.6084/m9.figshare.12851950
title: Regional variation in green-up timing along a caribou migratory corridor: Spatial associations with snowmelt and temperature

description: Spring green-up in arctic and alpine systems is predominantly controlled by temperature and snowmelt timing preceding and during the growing season. Variation in the timing of green-up across space is an important aspect of resource variability with which mobile herbivores must contend. Here, we measure the explanatory power of abiotic drivers of green-up in a Low Arctic region of west Greenland, host to a migratory caribou population. We identify inconsistent relationships between green-up and abiotic drivers across space. Whereas green-up timing is most closely related to snowmelt in some areas, in others it is most closely related to spring temperature. The negative correlation between the explanatory power of snowmelt and temperature suggests that at broad scales, where green-up is more constrained by snow cover, such as moist, mountainous coastal areas, it is less constrained by temperature. Where snow is less persistent through winter, such as cold, dry inland areas, temperature becomes the predominant factor driving green-up. If the principal driver of spring plant growth is inconsistent across a region, long-term trends in resource phenology could vary spatially. For seasonal migrants like caribou, synchronizing migration timing with resource phenology may be complicated by discordant interannual change across drivers of green-up timing.
DOI: 10.6084/m9.figshare.12851950.v1
title: Regional variation in green-up timing along a caribou migratory corridor: Spatial associations with snowmelt and temperature

description: Spring green-up in arctic and alpine systems is predominantly controlled by temperature and snowmelt timing preceding and during the growing season. Variation in the timing of green-up across space is an important aspect of resource variability with which mobile herbivores must contend. Here, we measure the explanatory power of abiotic drivers of green-up in a Low Arctic region of west Greenland, host to a migratory caribou population. We identify inconsistent relationships between green-up and abiotic drivers across space. Whereas green-up timing is most closely related to snowmelt in some areas, in others it is most closely related to spring temperature. The negative correlation between the explanatory power of snowmelt and temperature suggests that at broad scales, where green-up is more constrained by snow cover, such as moist, mountainous coastal areas, it is less constrained by temperature. Where snow is less persistent through winter, such as cold, dry inland areas, temperature becomes the predominant factor driving green-up. If the principal driver of spring plant growth is inconsistent across a region, long-term trends in resource phenology could vary spatially. For seasonal migrants like caribou, synchronizing migration timing with resource phenology may be complicated by discordant interannual change across drivers of green-up timing.
DOI: 10.6084/m9.figshare.12184830.v1
title: Seasonal source water and flow path insights from a year of sampling in the Chamkhar Chhu basin of Central Bhutan

description: Hydrologic processes that control river flow in Bhutan’s Chamkhar Chhu basin are important for understanding water supply vulnerability to downstream populations in a changing climate. Seasonal source waters and flow paths of streamflow of the basin were determined using isotopic and geochemical tracers for water year 2016. Samples including surface water, groundwater, glacier meltwater, and precipitation were collected in premonsoon, monsoon, and postmonsoon seasons along an elevation transect from 2,538 to 5,158 m. Solute trends in surface waters demonstrate the major influence that tributaries can have on main stem hydrochemistry and the increasingly important role of groundwater below 3,500 m. Groundwater’s role in flow is supported by a two-component hydrograph separation using SO<sub>4</sub><sup>2−</sup> as a tracer and shows that groundwater is especially important to river flow in the premonsoon. Source waters to river flow were calculated using δ<sup>18</sup>O as a tracer, indicating that rain and meltwater are more evenly important across the elevation transect in the early monsoon period than in the postmonsoon period when ice melt contributions rapidly wane with distance from the glacier.
DOI: 10.6084/m9.figshare.12184830
title: Seasonal source water and flow path insights from a year of sampling in the Chamkhar Chhu basin of Central Bhutan

description: Hydrologic processes that control river flow in Bhutan’s Chamkhar Chhu basin are important for understanding water supply vulnerability to downstream populations in a changing climate. Seasonal source waters and flow paths of streamflow of the basin were determined using isotopic and geochemical tracers for water year 2016. Samples including surface water, groundwater, glacier meltwater, and precipitation were collected in premonsoon, monsoon, and postmonsoon seasons along an elevation transect from 2,538 to 5,158 m. Solute trends in surface waters demonstrate the major influence that tributaries can have on main stem hydrochemistry and the increasingly important role of groundwater below 3,500 m. Groundwater’s role in flow is supported by a two-component hydrograph separation using SO<sub>4</sub><sup>2−</sup> as a tracer and shows that groundwater is especially important to river flow in the premonsoon. Source waters to river flow were calculated using δ<sup>18</sup>O as a tracer, indicating that rain and meltwater are more evenly important across the elevation transect in the early monsoon period than in the postmonsoon period when ice melt contributions rapidly wane with distance from the glacier.
DOI: 10.6084/m9.figshare.12293333
title: Emergence of steeply stratified permafrost thaw ponds changes zooplankton ecology in subarctic freshwaters

description: Climate change and associated permafrost thaw are creating new shallow waterbodies in vast regions of the circumpolar Arctic. These thaw ponds are characterized by high concentrations of colored dissolved organic matter originating from the degrading watershed, inducing a strong vertical thermal and oxygen (O<sub>2</sub>) stratification. We investigated the zooplankton community and biomass in eight subarctic thaw ponds and evaluated how zooplankton respond to this stratification. In a subset of three ponds, we further examined how other environmental variables, including essential fatty acids (EFA) concentration and phytoplankton, bacteria, and larval phantom midge <i>Chaoborus</i> biomass stratify and contribute to the vertical distribution of zooplankton in this increasingly common type of arctic freshwater system. The zooplankton community was extremely abundant in all ponds (up to 3,548 ind L<sup>−1</sup>) and dominated mainly by rotifers (35–93 percent of the biomass). Most zooplankton aggregated at the interface between the shallow well-oxygenated mixed surface layer and the deeper hypoxic but algal-rich stratified layer, and their distribution was affected by a combination of O<sub>2</sub>, <i>Chaoborus</i>, phytoplankton, and EFA that were supplied from opposite directions. Our findings show how water column stratification deeply affects the ecology of planktonic organisms in circumpolar freshwaters and indicate Arctic zooplankton species composition is expected to deeply change with the ongoing warming and browning.
DOI: 10.6084/m9.figshare.12293333.v1
title: Emergence of steeply stratified permafrost thaw ponds changes zooplankton ecology in subarctic freshwaters

description: Climate change and associated permafrost thaw are creating new shallow waterbodies in vast regions of the circumpolar Arctic. These thaw ponds are characterized by high concentrations of colored dissolved organic matter originating from the degrading watershed, inducing a strong vertical thermal and oxygen (O<sub>2</sub>) stratification. We investigated the zooplankton community and biomass in eight subarctic thaw ponds and evaluated how zooplankton respond to this stratification. In a subset of three ponds, we further examined how other environmental variables, including essential fatty acids (EFA) concentration and phytoplankton, bacteria, and larval phantom midge <i>Chaoborus</i> biomass stratify and contribute to the vertical distribution of zooplankton in this increasingly common type of arctic freshwater system. The zooplankton community was extremely abundant in all ponds (up to 3,548 ind L<sup>−1</sup>) and dominated mainly by rotifers (35–93 percent of the biomass). Most zooplankton aggregated at the interface between the shallow well-oxygenated mixed surface layer and the deeper hypoxic but algal-rich stratified layer, and their distribution was affected by a combination of O<sub>2</sub>, <i>Chaoborus</i>, phytoplankton, and EFA that were supplied from opposite directions. Our findings show how water column stratification deeply affects the ecology of planktonic organisms in circumpolar freshwaters and indicate Arctic zooplankton species composition is expected to deeply change with the ongoing warming and browning.