Rapid growth rate responses of terrestrial bacteria to field warming on the Antarctic Peninsula.

Ice-free terrestrial environments of the western Antarctic Peninsula are expanding and subject to colonization by new microorganisms and plants, which control biogeochemical cycling. Measuring growth rates of microbial populations and ecosystem carbon flux is critical for understanding how terrestrial ecosystems in Antarctica will respond to future warming. We implemented a field warming experiment in early (bare soil; +2 °C) and late (peat moss-dominated; +1.

Is bog water chemistry affected by increasing N and S deposition from oil sands development in Northern Alberta, Canada?

Nitrogen and sulfur emissions from oil sands operations in northern Alberta, Canada have resulted in increasing deposition of N and S to the region's ecosystems. To assess whether a changing N and S deposition regime affects bog porewater chemistry, we sampled bog porewater at sites at different distances from the oil sands industrial center from 2009 to 2012 (10-cm intervals to a depth of 1 m) and from 2009 to 2019 (top of the bog water table only). We hypothesized that: (1) as atmospheric N and S deposition increases with increasing proximity to the oil sands industrial center, surface porewater concentrations of NH, NO, DON, and SO would increase and (2) with increasing N and S deposition, elevated porewater concentrations of NH, NO, DON, and SO would be manifested increasingly deeper into the peat profile.

Perceptions of preparedness: How hospital-based orientation can enhance the transition from academic to clinical learning.

Background: Clinical placements are essential for applied learning experiences in health professions education. Unfortunately, there is little consensus on how best to prepare learners for the transition between academic and clinical learning. We explored learners' perceptions of hospital-based orientation and resulting preparedness for clinical placement.

Experimental nitrogen addition alters structure and function of a boreal poor fen: Implications for critical loads.

Bogs and fens cover 6 and 21%, respectively, of the 140,329 km Oil Sands Administrative Area in northern Alberta. Regional background atmospheric N deposition is low (<2 kg N ha yr), but oil sands development has led to increasing N deposition (as high as 17 kg N ha yr). To examine responses to N deposition, over five years, we experimentally applied N (as NHNO) to a poor fen near Mariana Lake, Alberta, unaffected by oil sands activities, at rates of 0, 5, 10, 15, 20, and 25 kg N ha yr, plus controls (no water or N addition).

Differential Effects of High Atmospheric N and S Deposition on Bog Plant/Lichen Tissue and Porewater Chemistry across the Athabasca Oil Sands Region.

Oil extraction and development activities in the Athabasca Oil Sands Region of northern Alberta, Canada, release NO, SO, and NH to the atmosphere, ultimately resulting in increasing N and S inputs to surrounding ecosystems through atmospheric deposition. Peatlands are a major feature of the northern Alberta landscape, with bogs covering 6-10% of the land area, and fens covering 21-53%. Bulk deposition of NH-N, NO-N, dissolved inorganic N (DIN), and SO-S, was quantified using ion-exchange resin collectors deployed at 23 locations, over 1-6 years.