129 research outputs found
Population and major land use in the Great Barrier Reef catchment area spatial and temporal trends
The purpose of this report was to gather geographical and statistical information on the Great Barrier Reef Catchment, the majority of which was compiled in 1998. This information is intended to support future studies on predicting the impact of land-based activities on the Great Barrier Reef.
This report originated from an identified need to expand the information base available to water quality researchers in terms of the spatial and temporal extent of anthropogenic disturbance within the Great Barrier Reef Catchment Area. A Geographic Information System (GIS) of existing historic and spatial datasets has been compiled to demonstrate trends in population and major land use with a view to providing a framework for current water quality research and in monitoring the Great Barrier Reef lagoon. Elsewhere, GIS has been used to analyse patterns of urbanisation and land use change within the catchments of large semi-enclosed marine ecosystems. The report provides a background to the history of modification of the Great Barrier Reef Catchment based on existing available datasets. The report is structured to give an initial description of the Great Barrier Reef lagoon and catchment area, followed by a description of the main types of catchment modification since settlement
Magnetic Quay water quality and sediment baseline study 1989
A study of water quality and water column sediment loads was carried out in
the period mid-December 1988 to mid-February 1989 on the south-east facing
fringing reefs of Magnetic Island. The study aimed at providing a baseline
before construction commenced on the marina/hotel development planned for
the northern end of Nelly Bay. Although it was realized that a complete
baseline, allowing for natural seasonal and meteorological variability,
could not be produced in two months, as much data as was logistically
possible to obtain ·was collected including data from periods of contrasting
weather conditions. An associated benthic biota and sedimentation study
provided a benthos baseline and measured sediment deposition in sediment
traps in the same areas
A pilot study of baseline levels of water quality around Green Island
A pilot study was undertaken at Green Island in June 1989 to assess the spatial and
temporal variation of a range of water quality parameters. It was a precursor to the
implementation of a proposed baseline study of water quality around Green Island to
ensure the optimum allocation of sampling in a cost effective manner
Chapter 19: Vulnerability of coastal and estuarine habitats in the Great Barrier Reef to climate change
This chapter attempts to address the vulnerability of the CEM in the Great Barrier Reef region to global
climate change. It does not consider individual habitats (eg reefs or seagrasses) but goes beyond
the individual species and habitat assessments, to consider impacts on the whole coastal marine
community complex, and the ecological processes that support its functioning.This is Chapter 19 of Climate change and the Great Barrier Reef: a vulnerability assessment. The entire book can be found at http://hdl.handle.net/11017/13
Brane Bremsstrahlung in DBI Inflation
We consider the effect of trapped branes on the evolution of a test brane
whose motion generates DBI inflation along a warped throat. The coupling
between the inflationary brane and a trapped brane leads to the radiation of
non-thermal particles on the trapped brane. We calculate the Gaussian spectrum
of the radiated particles and their backreaction on the DBI motion of the
inflationary brane. Radiation occurs for momenta lower than the speed of the
test brane when crossing the trapped brane. The slowing down effect is either
due to a parametric resonance when the interaction time is small compared to
the Hubble time or a tachyonic resonance when the interaction time is large. In
both cases the motion of the inflationary brane after the interaction is
governed by a chameleonic potential,which tends to slow it down. We find that a
single trapped brane can hardly slow down a DBI inflaton whose fluctuations
lead to the Cosmic Microwave Background spectrum. A more drastic effect is
obtained when the DBI brane encounters a tightly spaced stack of trapped
branes.Comment: 20 pages, 1 figur
Bridging geometries and potentials in DBI cosmologies
We investigate the link between the warp function and the potential in DBI
cosmologies in connection with the possibility they represent power-law
solutions. A prescription is given to take advantage of the known result that
given a warp factor there is always a choice of potential resulting in a
constant ratio between pressure and energy density. The method is illustrated
with examples with interesting models for either the warp factor or the
potential. We complete this investigation by giving a recipe to exploit
symmetries in order to generate new solutions from existing ones; this method
can be applied, for instance, to the power-law cosmologies obtained using our
prescription.Comment: 7 pages, 3 figures, revte
Global extent and drivers of mammal population declines in protected areas under illegal hunting pressure
Illegal hunting is a persistent problem in many protected areas, but an overview of the extent of this problem and its impact on wildlife is lacking. We reviewed 40 years (1980–2020) of global research to examine the spatial distribution of research and socio-ecological factors influencing population decline within protected areas under illegal hunting pressure. From 81 papers reporting 988 species/site combinations, 294 mammal species were reported to have been illegally hunted from 155 protected areas across 48 countries. Research in illegal hunting has increased substantially during the review period and showed biases towards strictly protected areas and the African continent. Population declines were most frequent in countries with a low human development index, particularly in strict protected areas and for species with a body mass over 100 kg. Our results provide evidence that illegal hunting is most likely to cause declines of large-bodied species in protected areas of resource-poor countries regardless of protected area conservation status. Given the growing pressures of illegal hunting, increased investments in people’s development and additional conservation efforts such as improving anti-poaching strategies and conservation resources in terms of improving funding and personnel directed at this problem are a growing priority
Star clusters near and far; tracing star formation across cosmic time
© 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s11214-020-00690-x.Star clusters are fundamental units of stellar feedback and unique tracers of their host galactic properties. In this review, we will first focus on their constituents, i.e.\ detailed insight into their stellar populations and their surrounding ionised, warm, neutral, and molecular gas. We, then, move beyond the Local Group to review star cluster populations at various evolutionary stages, and in diverse galactic environmental conditions accessible in the local Universe. At high redshift, where conditions for cluster formation and evolution are more extreme, we are only able to observe the integrated light of a handful of objects that we believe will become globular clusters. We therefore discuss how numerical and analytical methods, informed by the observed properties of cluster populations in the local Universe, are used to develop sophisticated simulations potentially capable of disentangling the genetic map of galaxy formation and assembly that is carried by globular cluster populations.Peer reviewedFinal Accepted Versio
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