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Kelp gull shell middens potentially facilitate root growth of non-native plants in AntarcticaNARA Subscribed
Ecosystem engineering is an important factor influencing species establishment in novel environments. Here we tested how shell middens created by kelp gulls ( Larus dominicanus ) affect the growth of candidate non-native plants under simulated Antarctic conditions. Calcium compounds derived from the shells raised the organic Antarctic substrate pH from 6.0 to 7.3 and resulted in increased plant biomass (21–100%) over a 14-week...
Community assembly among potential invasive plants in Antarctica shaped by life history characteristics and climate warmingNARA Subscribed
Species arrival sequence in new habitats impacts plant community development. This ‘priority-effect’ is documented, but mechanisms by which early arriving plants dominate future communities are less clear, complicating our ability to predict community assembly under future climate warming and assess invasive species threats. This is particularly important for ecosystems that are vulnerable to invasive species, such as those of...
Birds are a large nutrient vector from marine to terrestrial environments where the increased nutrient input typically results in greater primary production and enhanced microbial activity. Associated invertebrate populations however, show large response variability to bird nutrient subsidies. To explain this variable invertebrate response, we performed a meta-analysis (50 articles ranging from polar to tropical regions) where...
Global maps of soil temperatureNARA Subscribed
Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1‐km 2 r...
Statistical upscaling of ecosystem CO 2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertaintiesNARA Subscribed
The regional variability in tundra and boreal carbon dioxide (CO 2 ) fluxes can be high, complicating efforts to quantify sink‐source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO 2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we com...
Variable temperature effects of Open Top Chambers at polar and alpine sites explained by irradiance and snow depthNARA Subscribed
Environmental manipulation studies are integral to determining biological consequences of climate warming. Open Top Chambers ( OTC s) have been widely used to assess summer warming effects on terrestrial biota, with their effects during other seasons normally being given less attention even though chambers are often deployed year‐round. In addition, their effects on temperature extremes and freeze‐thaw events are poorly docume...
Extreme weather events can have negative impacts on species survival and community structure when surpassing lethal thresholds. Extreme winter warming events in the A rctic rapidly melt snow and expose ecosystems to unseasonably warm air (2–10 °C for 2–14 days), but returning to cold winter climate exposes the ecosystem to lower temperatures by the loss of insulating snow. Soil animals, which play an integral part in soil proc...
Impacts of multiple extreme winter warming events on sub‐Arctic heathland: phenology, reproduction, growth, and CO 2 flux responsesNARA Subscribed
Extreme weather events can have strong negative impacts on species survival and community structure when surpassing lethal thresholds. Extreme, short‐lived, winter warming events in the Arctic rapidly melt snow and expose ecosystems to unseasonably warm air (for instance, 2–10 °C for 2–14 days) but upon return to normal winter climate exposes the ecosystem to much colder temperatures due to the loss of insulating snow. Single...
EATB Donor Case Workshop 2007NARA Subscribed
Impacts of extreme winter warming in the sub‐Arctic: growing season responses of dwarf shrub heathlandNARA Subscribed
Climate change scenarios predict an increased frequency of extreme climatic events. In Arctic regions, one of the most profound of these are extreme and sudden winter warming events in which temperatures increase rapidly to above freezing, often causing snow melt across whole landscapes and exposure of ecosystems to warm temperatures. Following warming, vegetation and soils no longer insulated below snow are then exposed to ra...
Climate change effects on organic matter decomposition rates in ecosystems from the Maritime Antarctic and Falkland IslandsNARA Subscribed
Antarctic terrestrial ecosystems have poorly developed soils and currently experience one of the greatest rates of climate warming on the globe. We investigated the responsiveness of organic matter decomposition in Maritime Antarctic terrestrial ecosystems to climate change, using two study sites in the Antarctic Peninsula region (Anchorage Island, 67°S; Signy Island, 61°S), and contrasted the responses found with those at the...
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