961 resultados para Coastal changes
Resumo:
BACKGROUND: Wheat can be stored for many months before being fumigated with phosphine to kill insects, so a study was undertaken to investigate whether the sorptive capacity of wheat changes as it ages. Wheat was stored at 15 or 25C and 55% RH for up to 5.5 months, and samples were fumigated at intervals to determine sorption. Sealed glass flasks (95% full) were injected with 1.5 mg L-1 of phosphine based on flask volume. Concentrations were monitored for 11 days beginning 2 h after injection. Some wheat samples were refumigated after a period of ventilation. Several fumigations of wheat were conducted to determine the pattern of sorption during the first 24 h. RESULTS: Phosphine concentration declined exponentially with time from 2 h after injection. Rate of sorption decreased with time spent in storage at either 15 or 25C and 55% RH. Rate of sorption tended to be lower when wheat was refumigated, but this could be explained by time in storage rather than by refumigation per se. The data from the 24 h fumigations did not fit a simple exponential decay equation. Instead, there was a rapid decline in the first hour, with phosphine concentration falling much more slowly thereafter. CONCLUSIONS: The results have implications for phosphine fumigation of insects in stored wheat. Both the time wheat has spent in storage and the temperature at which it has been stored are factors that must be considered when trying to understand the impact of sorption on phosphine concentrations in commercial fumigations.
Resumo:
Protection of coastal wetland environments is an important prerequisite to effective and sustainable fisheries management and conservation of habitats for the use of future generations. Mangroves, saltmarshes and seagrasses directly support local and offshore fisheries through the provision of food, shelter, breeding and nursery grounds. As such, these vegetated wetland environments along with sandbars, mudflats, rocky foreshores and reefs have significant economic value as well as their intrinsic aesthetic and ecological values. This report summarises the results of the mapping undertaken in the Gulf of Carpentaria Region from the Queensland/Northern Territory border eastwards to the western bank of the Flinders River (hereafter called the Gulf Study Area). The study was undertaken in order to: 1. document and map coastal wetlands of the Gulf Study Area; 2. document levels of existing disturbance to and protection of these wetlands; 3. examine existing recreational, indigenous and commercial fisheries of the region; 4. evaluate the conservation values of the areas investigated from the viewpoint of fisheries productivity and as habitat for important and/or threatened species for future FHA/Marine Protected Area (MPA) declaration. Dataset URL Link: Queensland Coastal Wetlands Resources Mapping data. [Dataset]
Resumo:
Protection of coastal wetland environments is an important prerequisite to effective and sustainable inshore fisheries management and conservation of habitats for use by future generations. Mangroves, saltmarshes, seagrasses and non vegetated habitats directly support local and regional inshore and offshore fisheries through the provision of food, shelter, breeding and nursery grounds. As such, these wetland environments have significant economic value as well as their intrinsic aesthetic and ecological values. This report summarises the results of the mapping undertaken in the Central Queensland Coast from Sand Bay to Keppel Bay (hereafter referred to as the Study Area). The study was undertaken in order to: 1. document and map the coastal wetland communities along the Queensland coastline from Sand Bay (20.93°S, 149.04°E) to Keppel Bay (23.65°S, 151.07°E); 2. document levels of existing disturbance to and protection of the wetlands; 3. examine existing recreational and commercial fisheries in the region; and 4. evaluate the conservation values of the areas investigated from the viewpoint of fisheries productivity and as habitat for important and/or threatened species. Dataset URL Link: Queensland Coastal Wetlands Resources Mapping data. [Dataset]
Resumo:
This report provides key resource data for the ongoing assessment of the requirement for additional Marine Protected Areas (e.g. FHAs under the Queensland Fisheries Act 1994) in regions of high fish habitat value in northern Queensland from Cape Tribulation to Bowling Green Bay (hereafter referred to as the Study Area). The study also provides baseline information on the coastal wetlands within this Study Area for consideration in the Ramsar site nomination process. The Study Area extends from Cape Tribulation (16o 6’S, 145o 24’E) to Bowling Green Bay (19o 30’S, 147o 24’E) in tropical north Queensland. The project aimed to: 1. document and map the coastal wetland communities of the Study Area; 2. document levels of existing disturbance to and protection of the wetlands; 3. examine existing recreational, indigenous and commercial fisheries resources in the region; 4. evaluate the conservation values of the areas investigated from the viewpoint of fisheries productivity and as habitat for important and/or threatened species for future FHA/MPA declaration. Dataset URL Link: Queensland Coastal Wetlands Resources Mapping data. [Dataset]
Resumo:
A project to investigate the coastal wetland resources of the Burdekin Delta, north Queensland, was undertaken as part of the long-term assessment of the coastal fisheries resources of Queensland. Extending from November 1993 to May 1995, fieldwork was undertaken in November 1993 and August 1994. The scope of the coastal wetlands resources investigation of the Burdekin Delta for declaration as a Fish Habitat Area was: 1. To document and map the marine wetland vegetation communities in the Burdekin River delta. 2. To document levels of existing disturbance to wetlands, existing recreational and commercial fisheries resources, and existing fishing activities. 3. To evaluate the conservation values of the areas investigated from the viewpoint of fisheries productivity and as habitat for important/threatened species. 4. To initiate Fish Habitat Area declaration under Section 120 of the Queensland Fisheries Act 1994 with formal consultation to all stakeholders. This report concentrates on Points 1 and 3, the documentation of the marine wetland vegetation communities and the evaluation of conservation values from a fisheries viewpoint. Dataset URL Link: Queensland Coastal Wetlands Resources Mapping data. [Dataset]
Resumo:
The wetland resources of the Queensland coastline have been mapped as a baseline dataset for Marine Protected Area investigation and particularly Fish Habitat Area (FHA) declaration, Ramsar site nomination and continued monitoring of these important fish habitats. This report summarises the results of the mapping undertaken in the Bowen region from the East Coast of Cape Upstart (Abbot Bay) to Gloucester Island (encompassing Edgecumbe Bay). The study was undertaken in order to: 1. document and map the coastal wetland communities within the Bowen region; 2. document levels of existing disturbance to and protection of the wetlands; 3. examine existing recreational and commercial fisheries in the region; and 4. evaluate the significance of the coastal wetlands in the region. Dataset URL Link: Queensland Coastal Wetlands Resources Mapping data. [Dataset]
Resumo:
In February 2004, Redland Shire Council with help from a Horticulture Australia research project was able to establish a stable grass cover of seashore paspalum (Paspalum vaginatum) on a Birkdale park where the soil had previously proved too salty to grow anything else. Following on from their success with this small 0.2 ha demonstration area, Redland Shire has since invested hundreds of thousands of dollars in successfully turfing other similarly “impossible” park areas with seashore paspalum. Urban salinity can arise for different reasons in different places. In inland areas such as southern NSW and the WA wheatbelt, the usual cause is rising groundwater bringing salt to the surface. In coastal sites, salt spray or periodic tidal inundation can result in problems. In Redland Shire’s case, the issue was compacted marine sediments (mainly mud) dug up and dumped to create foreshore parkland in the course of artificial canal developments. At Birkdale, this had created a site that was both strongly acid and too salty for most plants. Bare saline scalds were interspersed by areas of unthrifty grass. Finding a salt tolerant grass is no “silver bullet” or easy solution to salinity problems. Rather, it buys time to implement sustainable long-term establishment and maintenance practices, which are even more critical than with conventional turfgrasses. These practices include annual slicing or coring in conjunction with gypsum/dolomite amendment and light topdressing with sandy loam soil (to about 1 cm depth), adequate maintenance fertiliser, weed control measures, regular leaching irrigation was applied to flush salts below the root zone, and irrigation scheduling to maximise infiltration and minimise run off. Three other halophytic turfgrass species were also identified, each of them adapted to different environments, management regimes and uses. These have been shortlisted for larger-scale plantings in future work.
Resumo:
1:100,000 coastal wetland vegetation mapping for Queensland including mangrove communities, saltpans and saline grasslands. Mapping taken from Landsat TM images with ground truthing. Additional metadata is available for details of techniques and accuracy for each section of coastline. Data Currency for each section of coast: NT border to Flinders River - 1995 SE Gulf of Carpentaria - 1987, 1988, 1991, 1992 Cape York Peninsula - 1986-88, 1991 Cape Trib to Bowling Green Bay - 1997-99 The Burdekin Region - 1991 The Bowen Region - 1994-95 The Whitsunday Region - 1997 Repulse Bay - 1989 Central Qld - 1995, 1997 The Curtis Coast Region - 1997 Round Hill Head to Tin Can Inlet - 1997 Moreton Region - 1995. Article Links: 1/ #1662. Queensland Coastal Wetland Resources: the Northern Territory Border to Flinders River. Project Report. Information Series QI00099. 2/ #1663. Queensland Coastal Wetland Resources: Sand Bay to Keppel Bay. Project Report. Information Series QI00100. 3/ #1664. Queensland Coastal Wetland Resources: Cape Tribulation to Bowling Green Bay. Project Report. Information Series QI01064. 4/ #1666. Coastal Wetlands Resources Investigation of the Burdekin Delta for declaration as fisheries reserves. Report to Ocean Rescue 2000. Project Report. 5/ #1667. Queensland Coastal Wetland Resource Investigation of the Bowen Region: Cape Upstart to Gloucester Island. Project Report. 6/ #1784. Resource Assessment of the Tidal Wetland Vegetation of Western Cape York Peninsula, North Queensland, Report to Ocean Rescue 2000. Project Report. 7/ #1785. Marine Vegetation of Cape York Peninsula. Cape York Peninsula Land Use Strategy. Project Report. 8/ #3544. Queensland Coastal Wetland Resources: The Whitsunday Region. Project Report.Information Series QI01065. 9/ #3545. Queensland Coastal Wetland Resources: Round Hill Head to Tin Can Inlet. Project Report. Information Series QI99081.
Resumo:
On the basis of a detailed Monte Carlo study, it is found that considerable molecular reorientation occurs on the formation of the glassy state of isopentane. The reorientational contribution to the increase in the intermolecular energy on vitrification is at least 50% and reorientational freezing plays a major role near the glass transition. Annealing affects the structure of the glass by a rearrangement involving molecular reorientation.
Resumo:
4..T~iouridine, a thionucleoside present in the transfer RNA of the free living, nitrogen-fixing ?actenu~ Azotobacter »inelandii shows a culture condition dependent change. When thebacterium IS grown Intheabsen~e ofanyfixed nit~ogen thetRNA contains 4-thiouridine to theextent of 45% of the total sulphur Incorporated. This gets reduced to 5%when the bacterium is grown in the presen~e of.e~ces~ ofamm~nium salt.Instead, a new thionucleoside which appears to be a derivative of 4-thloundlne IS found In the tRNA to the extent of 28%of the total sulphur incorporated.
Resumo:
During the thermal decomposition of orthorhombic ammonium perchlorate (AP) at 230°C, where the decomposition is only up to 30 wt %, there is an accumulation in the solid of acids, the concentration of which increases up to 15% decomposition, after which it decreases till it reaches the original value. Similar observations have been made in the polystyrene (PS)/AP propellant systems. Aging studies of PS/AP propellants have been carried out earlier [1], where it has been shown that for the aged propellants the thermal decomposition (TD) rate at 230°C and 260°C and ambient pressure burning rate (Image ) both increase and this increase is due to the formation of reactive intermediate “polystyrene peroxide (PSP).” In the present studies it has been observed that during the aging of the propellant at 150°C, the acid is formed and gets accumulated in the propellant, which may also be responsible for the increase in TD rate and perhaps may be more effective than PSP.
Resumo:
High concentration of L-cystine (0.25%) when present in a glucose-mineral salt medium inhibited sporulation-specific events like protease production, calcium uptake and dipicolinic acid synthesis inBacillus thuringiensis var.thuringiensis. In addition, the enzymes of the Krebs cycle from aconitase onwards were completely inhibited by a high concentration of cystine. At a low concentration of cystine (0.05%), none of the above mentioned macromolecular changes were affected. Lipid synthesis monitored by [1,214 C]-acetate incorporation into lipid as well as into whole cells was completely inhibited.