816 research outputs found
Novel resources: opportunities for and risks to species conservation
During the Anthropocene, ongoing rapid environmental changes are exposing many species to novel resources. However, scientistsâ understanding of what novel resources are and how they impact species is still rudimentary. Here, we used a resourceâbased approach to explore novel resources. First, we conceptualized novel resource use by species along two dimensions of novelty: namely, ecosystem novelty and resource novelty. We then examined characteristics that influence a speciesâ response to a novel resource and how novel resources can affect individuals, populations, species, and communities. In addition, we discuss potential management complications associated with novel resource use by threatened species. As conservation and management embrace global environmental change, it is critical that ecologists improve the current understanding of the opportunities and risks that novel resources present to species conservation
Remediation of PCB contaminated sediments using activated carbon: Assessing efficiency and robustness using equilibrium sampling
Remediation of PCB contaminated sediments using activated carbon: Thermodynamic exposure assessment
Cross-validation of equilibrium sampling and non-equilibrium passive sampling methods in PCB contaminated sediments
Recommended from our members
Sampling uncertainty in gridded sea surface temperature products and Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) data
Sea surface temperature (SST) data are often provided as gridded products, typically at resolutions of order 0.05 degrees from satellite observations to reduce data volume at the request of data users and facilitate comparison against other products or models. Sampling uncertainty is introduced in gridded products where the full surface area of the ocean within a grid cell cannot be fully observed because of cloud cover. In this paper we parameterise uncertainties in SST as a function of the percentage of clear-sky pixels available and the SST variability in that subsample. This parameterisation is developed from Advanced Along Track Scanning Radiometer (AATSR) data, but is applicable to all gridded L3U SST products at resolutions of 0.05-0.1 degrees, irrespective of instrument and retrieval algorithm, provided that instrument noise propagated into the SST is accounted for. We also calculate the sampling uncertainty of ~0.04 K in Global Area Coverage (GAC) Advanced Very High Resolution Radiometer (AVHRR) products, using related methods
Global declines in coral reef calcium carbonate production under ocean acidification and warming
Role of carbonate burial in Blue Carbon budgets
Calcium carbonates (CaCO 3 ) often accumulate in mangrove and seagrass sediments. As CaCO 3 production emits CO 2 , there is concern that this may partially offset the role of Blue Carbon ecosystems as CO 2 sinks through the burial of organic carbon (C org ). A global collection of data on inorganic carbon burial rates (C inorg , 12% of CaCO 3 mass) revealed global rates of 0.8 TgC inorg yr â1 and 15â62 TgC inorg yr â1 in mangrove and seagrass ecosystems, respectively. In seagrass, CaCO 3 burial may correspond to an offset of 30% of the net CO 2 sequestration. However, a mass balance assessment highlights that the C inorg burial is mainly supported by inputs from adjacent ecosystems rather than by local calcification, and that Blue Carbon ecosystems are sites of net CaCO 3 dissolution. Hence, CaCO 3 burial in Blue Carbon ecosystems contribute to seabed elevation and therefore buffers sea-level rise, without undermining their role as CO 2 sinks. Š 2019, The Author(s)
In situ activated carbon (AC) amendment to limit bio-uptake from PCB contaminated sediment â A mesocosm study with three organisms
Signals for Lorentz Violation in Electrodynamics
An investigation is performed of the Lorentz-violating electrodynamics
extracted from the renormalizable sector of the general Lorentz- and
CPT-violating standard-model extension. Among the unconventional properties of
radiation arising from Lorentz violation is birefringence of the vacuum. Limits
on the dispersion of light produced by galactic and extragalactic objects
provide bounds of 3 x 10^{-16} on certain coefficients for Lorentz violation in
the photon sector. The comparative spectral polarimetry of light from
cosmologically distant sources yields stringent constraints of 2 x 10^{-32}.
All remaining coefficients in the photon sector are measurable in
high-sensitivity tests involving cavity-stabilized oscillators. Experimental
configurations in Earth- and space-based laboratories are considered that
involve optical or microwave cavities and that could be implemented using
existing technology.Comment: 23 pages REVTe
Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV
Results are presented from a search for a W' boson using a dataset
corresponding to 5.0 inverse femtobarns of integrated luminosity collected
during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV.
The W' boson is modeled as a heavy W boson, but different scenarios for the
couplings to fermions are considered, involving both left-handed and
right-handed chiral projections of the fermions, as well as an arbitrary
mixture of the two. The search is performed in the decay channel W' to t b,
leading to a final state signature with a single lepton (e, mu), missing
transverse energy, and jets, at least one of which is tagged as a b-jet. A W'
boson that couples to fermions with the same coupling constant as the W, but to
the right-handed rather than left-handed chiral projections, is excluded for
masses below 1.85 TeV at the 95% confidence level. For the first time using LHC
data, constraints on the W' gauge coupling for a set of left- and right-handed
coupling combinations have been placed. These results represent a significant
improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe
- âŚ