15 research outputs found
Specific Effect of Trace Metals on Marine Heterotrophic Microbial Activity and Diversity: Key Role of Iron and Zinc and Hydrocarbon-Degrading Bacteria
Marine microbes are an important control on the biogeochemical cycling of trace metals, but simultaneously, these metals can control the growth of microorganisms and the cycling of major nutrients like C and N. However, studies on the response/limitation of microorganisms to trace metals have traditionally focused on the response of autotrophic phytoplankton to Fe fertilization. Few reports are available on the response of heterotrophic prokaryotes to Fe, and even less to other biogeochemically relevant metals. We performed the first study coupling dark incubations with next generation sequencing to specifically target the functional and phylogenetic response of heterotrophic prokaryotes to Fe enrichment. Furthermore, we also studied their response to Co, Mn, Ni, Zn, Cu (individually and mixed), using surface and deep samples from either coastal or open-ocean waters. Heterotrophic prokaryotic activity was stimulated by Fe in surface openâocean, as well as in coastal, and deep open-ocean waters (where Zn also stimulated). The most susceptible populations to trace metals additions were uncultured bacteria (e.g., SAR324, SAR406, NS9, and DEV007). Interestingly, hydrocarbon-degrading bacteria (e.g., Thalassolituus, Marinobacter, and Oleibacter) benefited the most from metal addition across all waters (regions/depths) revealing a predominant role in the cycling of metals and organic matter in the ocean.© 2018 Baltar, GutiĂ©rrez-RodrĂguez, Meyer, Skudelny, Sander, Thomson, Nodder, Middag and Morale
River Dog: Re-imagining and re-representing the environment and de-idealising the rural in New Zealand film
Policy environment for the tourism sector's adaptation to climate change in the South Pacific - the case of Samoa
Samoa and its neighbouring Pacific Island Countries are highly vulnerable to climate change risks because their population and infrastructure are mostly located on low-lying coastal areas. Impacts of climate change are potentially disastrous to tourism, the major economic sector in the region. This research examines the conduciveness of the policy environment in Samoa for the tourism sector to adapt to climate change along three dimensions: stakeholdersâ will and commitment, resources available, and policy-making mechanisms [Wong, E.P.Y., Mistilis, N., & Dwyer, L. (2011). A framework for analyzing intergovernmental collaboration â the case of ASEAN tourism. Tourism Management, 32, 367â376]. Samoa is used as an exemplar case study to understand how the Pacific island tourism sector can best adapt to climate change. It was found that the policy environment in Samoa is generally conducive. However, there is a strong need for closer publicâprivate cooperation
Phosphorus fertilizer form affects phosphorus loss to waterways: a paired catchment study
An Integrated Approach for Predicting Fates of Reintroductions with Demographic Data from Multiple Populations
Rapid basal melting of the Greenland Ice Sheet from surface meltwater drainage (dataset)
Subglacial hydrologic systems regulate ice sheet flow, causing acceleration or deceleration, depending on hydraulic efficiency and the rate at which surface meltwater is delivered to the bed. Because these systems are rarely observed, ice sheet basal drainage represents a poorly integrated and uncertain component of models used to predict sea level changes. Dataset includes borehole data from a large Greenlandic outlet glacier
Use of Pollen and Ancient DNA as Conservation Baselines for Offshore Islands in New Zealand
Particulate matter in residential buildings in New Zealand : Part I. Variability of particle transport into unoccupied spaces with mechanical ventilation
Air pollution measured as particulate matter (PM) has been shown to be detrimental to human health and can lead to increased mortality rates. There are four main indoor sources of episodic PM emissions: smoking, cooking, cleaning and resuspension. This study has eliminated all human activity and provides data on the variability of the contribution from external sources via mechanical ventilation. The transportation of PM from an external to internal environment by mechanical ventilation is investigated in the same room in two, similar timber-framed houses, constructed identically apart from details affecting their airtightness.
There was significant variation in the transportation of PM from an external to internal environment in two similar houses ([PM] Control > [PM] Test (Ï=0.001)) despite both houses operating the same mechanical ventilation system. Mean internal PM10 concentrations=2.4 ÎŒgmâ3 (Control) and 1.3 ÎŒgmâ3 (Test) with corresponding mean external PM10 concentrations of 5.4 ÎŒgmâ3 and 5.2 ÎŒgmâ3 respectively. Particle removal efficiency between the two houses varied by approximately 20%. These findings indicate that there is considerable variation in filtration efficiencies even when the same mechanical ventilation system is in use in similar homes in the same location.
Control-Test PM10 0.40â0.23) and over time (Control PM10 0.40â0.18) which indicates that relationship between external and internal concentrations of PM is not linear and should therefore be used with caution. This questions simplifying Finf into one factor as there are likely to be multiple contributing factors. For example, the effect of air flow on particle adsorption to internal surfaces, natural variations in filter efficiency and variations in particle loss.
Over the duration of this study, PM concentrations decreased in both bedrooms by 52% (Control) and 37% (Test), which may be due to a number of factors including changes in internal environmental conditions, filter age and the cumulative effect of the use of mechanical ventilation over time reducing the transportation of PM into the houses