19 research outputs found
Identifying the land-based sources of suspended sediments, nutrients and pesticides discharged to the Great Barrier Reef from the Tully - Murray Basin, Queensland, Australia
Identification Tables for Common Minerals in Thin Section
This resource is a table for the identification of minerals with a petrographic microscope. The table lists minerals and their properties, including color in thin section, refractive index, extinction and extinction angle, interference figure, birefringence, twinning and other notes. The table is available in html for web viewing and RTF for printing. Educational levels: Undergraduate lower division, Undergraduate upper division
Water quality assessment for sustainable agriculture in the Wet Tropics: a community-assisted approach
A number of studies in north Queensland over the past two decades have concluded that large amounts of nutrients and sediments are exported from agricultural watersheds, particularly during wet season rainfall events. With the co-operation of a number of growers, runoff from Queensland Wet Tropics banana and cane farm paddocks in two distinct tropical river catchments was examined to provide an estimate of nutrient and sediment concentrations and export, with comparison to water quality of flow through a small urban lakes system. Median total nitrogen concentrations in cane drainage runoff (3110 ÎĽg N/L) were higher than for banana paddock drainage (2580 ÎĽg N/L), although the maximum concentration was recorded from a banana paddock (20,900 ÎĽg N/L). Nitrogen losses during post-event drainage flow were supplemented by high proportions of NOX (nitrate + nitrite) sourced from groundwater inputs. Banana paddocks had the highest maximum and median total phosphorus and TSS concentrations (5120 and 286 ÎĽg P/L, and 7250 and 75 mg/L respectively) compared to the cane farms (1430 and 50 ÎĽg P/L, and 1840 and 14 mg/L respectively). The higher phosphorus and TSS concentrations in the banana runoff were attributed to higher paddock slopes and a greater proportion of exposed ground surface during the wet season. Highest nutrient and TSS concentrations corresponded with samples collected near the peak discharge periods; however, the rising stage of the drainage flows, where the highest nutrient and TSS concentrations are often reported, were difficult to target because of the manual sampling strategy used. This study shows that high concentrations of nutrients and TSS occur in the runoff from cane and banana paddocks. Median total nitrogen, total phosphorus and TSS concentrations in flow through the urban lakes were 369 ÎĽg N/L, 16 ÎĽg P/L and 11 mg/L, respectively. Flux estimates of 9.2 kg N, 0.8 kg P and 126 kg TSS/ha were determined for drainage runoff from a banana paddock during a single intensive storm event
Townsville Ring Road (Douglas section). Review of environmental factors flora, fauna and water quality
[Extract] The Queensland Department of Main Roads (QDMR)has proposed to implement the Douglas arterial section of the Townsville Ring Road. This includes:
°the realignment and upgrade of University Drive leading towards the new Hospital site between CSIRO Davies Laboratory and James Cook University, including the construction of exit and entry ramps;
°realignment and upgrade of some of the existing Angus Smith Drive where University Drive will merge to it,;
°road construction approximately parallel with the unsealed section of Angus Smith Drive leading from the University entrance towards the Townsville City Council Water Treatment Plant,
°major bridge construction over the Ross River, including the construction of exit and entry ramps, and road realignment and widening of Upper Ross River Road.
The arterial road (refer to Maunsell McIntyre Pty. Ltd. aerial photo mosaic) will serve initially as an access route to south-western Townsville from the Upper Ross and eventually as a Townsville by-pass route via Hervey's Range Road.
In order to meet the requirements of the Review of Environmental Factors(REF) it is vital to identify, describe and assess the environmental advantages, disadvantages and constraints associated with the proposed route. To provide the basis for this assessment, the Australian Centre for Tropical Freshwater Research (ACTFR) was commissioned by Maunsell McIntyre Pty. Ltd. to assess the environmental values of the site with regard to potential impacts of the proposal.
An ACTFR aquatic chemist and ecologist conducted a field survey of the site on June 22, 1999. During this site visit, the proposed route was traversed and an assessment of the site made to document and evaluate the structure and floristic composition of the vegetation, provide an assessment of significance of habitats for fauna and determine the environmental value of water courses crossed by the proposed route.
This report forms the basis of the REF for issues pertaining to flora, fauna and water quality. A REF is intended solely to provide a preliminary assessment of the possible environmental effects of a proposed project to enable a decision to be made as to whether further and more detailed particulars are required prior to commencement of works
Turbid flow through a tropical reservoir (Lake Dalrymple, Queensland, Australia): responses to a summer storm event
The first flood event following a prolonged dry period is described for an impoundment, Lake Dalrymple, in tropical north-eastern Australia. The event, in January 1996, generated substantial flow in the two main inflow sources: the Burdekin River from the north and the Suttor River from the south. Flow through the Burdekin River peaked early and then subsided to a lower level, but flow through the Suttor River persisted at a moderate level for over 15 days after the initial inflow. An extensive water quality survey was conducted on 16 January 1996 (seven days after the initial dam overflow) to determine the nature of the inflows originating from the two major subcatchments feeding the reservoir as they entered and passed through the impoundment. The inflow comprising waters of high turbidity and low conductivity occupied the mid-column region along the two major inflow channels through the impoundment to the dam wall. The suspended particulate material in the form of silt and clay sized particles remained in suspension as the flow passed through the reservoir, due in part to the low ionic strength of the inflow and the relative densities of the inflowing and receiving waters. For both river sources, more than 50% of the total nitrogen and almost all of the total phosphorus were bound to the suspended particulate matter. Much of this was exported in the flow over the spillway. The highly turbid nature of the inflow resulted in strong attenuation of down-welling photosynthetically active radiation (up to maximum attenuation values of 12.24 m–1 in the reservoir where the euphotic depth was only 0.38 m). The irradiance reflectance and the scattering coefficient were considerably higher than any reported for other Australian inland waters. Concentrations of viable chlorophyll a in the surface waters were very low (maximum value 3.4 μg L–1) because of the highly turbid conditions and extensive dilution by the inflow. The results of this study provide an example of the significant impact a large inflow of turbid, low conductance water can have on a large reservoir in the arid tropics following a prolonged dry period. During inflow events such as the one described in this paper, the reservoir becomes riverine in nature, and large amounts of suspended particulate matter and associated nutrients are transported through the reservoir
Townsville Ring Road (Douglas section). Review of environmental factors flora, fauna and water quality
[Extract] The Queensland Department of Main Roads (QDMR)has proposed to implement the Douglas arterial section of the Townsville Ring Road. This includes:
°the realignment and upgrade of University Drive leading towards the new Hospital site between CSIRO Davies Laboratory and James Cook University, including the construction of exit and entry ramps;
°realignment and upgrade of some of the existing Angus Smith Drive where University Drive will merge to it,;
°road construction approximately parallel with the unsealed section of Angus Smith Drive leading from the University entrance towards the Townsville City Council Water Treatment Plant,
°major bridge construction over the Ross River, including the construction of exit and entry ramps, and road realignment and widening of Upper Ross River Road.
The arterial road (refer to Maunsell McIntyre Pty. Ltd. aerial photo mosaic) will serve initially as an access route to south-western Townsville from the Upper Ross and eventually as a Townsville by-pass route via Hervey's Range Road.
In order to meet the requirements of the Review of Environmental Factors(REF) it is vital to identify, describe and assess the environmental advantages, disadvantages and constraints associated with the proposed route. To provide the basis for this assessment, the Australian Centre for Tropical Freshwater Research (ACTFR) was commissioned by Maunsell McIntyre Pty. Ltd. to assess the environmental values of the site with regard to potential impacts of the proposal.
An ACTFR aquatic chemist and ecologist conducted a field survey of the site on June 22, 1999. During this site visit, the proposed route was traversed and an assessment of the site made to document and evaluate the structure and floristic composition of the vegetation, provide an assessment of significance of habitats for fauna and determine the environmental value of water courses crossed by the proposed route.
This report forms the basis of the REF for issues pertaining to flora, fauna and water quality. A REF is intended solely to provide a preliminary assessment of the possible environmental effects of a proposed project to enable a decision to be made as to whether further and more detailed particulars are required prior to commencement of works
Sediment dynamics of a large tropical river system: the Burdekin River and Lake Dalrymple, Australia
The Burdekin River Catchment is situated in the dry tropics region of Northern Queensland, Australia and covers 130,000km2. As the second largest catchment in the state it impacts significantly upon the Great Barrier Reef shelf system in terms of water, sediment and nutrient exports, but due to the seasonal nature of rainfall in the region, these impacts are highly episodic. In 1989, the Burdekin Falls Dam was built in order to provide a storage reservoir for irrigation. It was expected to act as a sediment trap, however the reservoir fills and overflows during flood events, which carry large amounts of suspended particulate matter. The reservoir is chronically turbid (>100NTU) and consequently discharge from the dam is no longer clear during the dry season, which may potentially cause adverse affects downstream.\ud
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Our investigation into the characteristics, source and fate of sediment in the Upper Burdekin catchment and its behaviour within the system has been undertaken within the two major inflowing rivers (Suttor and Burdekin Rivers) and impoundment area during baseflow and stormflow periods. Preliminary results indicate that the high turbidity relates to fine clay minerals of generally <10ÎĽm (kaolinite, smectite, muscovite), while sediment deposition within the reservoir has been minimal. A bi-modal distribution implies a second grainsize population related to an organic component. Benthic sediment exhibits a uni-modal distribution and as expected is coarser grained than suspended sediment. XRD work has shown that the composition of the suspended sediment in the inflowing rivers is similar and representative of catchment geology. Suspended sediment grainsize patterns from samples collected post-wet season in the Suttor river and reservoir are virtually identical, which along with turbidity and conductivity data implies that the persistent turbidity in the dam is largely controlled by inflow from the Suttor River
Environmental study of a proposed dam at Mount Douglas on the Belyando River
[Extract] Within the Burdekin River Catchment, suitable locations for further water infrastructure development are being considered. One of the options is a potential dam site at Mt. Douglas on the Belyando River, 10km upstream of its confluence with the Suttor River. The Belyando River catchment is the driest in the Burdekin basin and most of the recorded streamflow results from episodic large events. Despite its aridity, there are numerous in channel waterholes and off-river waterbodies in the lower reaches of the river and below its confluence with the Suttor River. The inundation area contains several of these waterholes.
This report provides a preliminary assessment of the likely environmental impacts of a dam at Mt. Douglas. Six permanent waterholes were examined during a brief field visit. Five of these were sampled for fish, crustaceans and water quality. A total of 12 fish species were caught, including two translocated predatory species (yellowbelly and sleepy cod). The two translocated species appear to be impacting on the abundance and diversity of smaller prey fish species. These smaller species were more abundant at off-river water bodies where the larger predatory fish were absent or in low numbers. Four fish species recorded for the Belyando River at Mt. Douglas in 1976 were not caught during this field survey. Failure to collect these four species may reflect insufficient sampling effort, but is more likely to reflect other factors such as altered habitat conditions and the effects of translocated piscivorous species.
Due to the topography of the site, a dam at Mt. Douglas would be a large, shallow impoundment with a greatly fluctuating shoreline. Hydrological data suggest that the dam would capture a significant proportion of medium-large flow events and most of the smaller flow events, thus altering the pattern of streamflow downstream and restricting options for fish passage within the catchment. Any dam at Mt. Douglas is likely to be even more turbid than the existing Burdekin Falls Dam and to have higher nutrient concentrations. The Belyando-Suttor is a major supplier of fine suspended sediment to the Burdekin Falls Dam which maintains that reservoir in a permanently turbid state, or essentially so. If a dam at Mt. Douglas reduces dry season flows such that water clarity improves in the Burdekin Fall sDam, then this should have a significant effect on its limnology. In some instances, this maybe beneficial but it is also likely to cause blue-green algal blooms. As water is released over much of the year for irrigation, the changes in water quality will also affect downstream receiving environments (eg, coastal wetlands) as well as the impoundment itself. The Suttor and Cape Rivers are not captured by this proposed dam and turbid discharges from these rivers may mask the effects of Mt. Douglas dam, but at present, there is insufficient data to test this idea.
Twenty-one regional ecosystems have been mapped for the impoundment area, including three listed as endangered and ten listed as of concern. In addition, one of the properties (Nairana) with a significant amount of land to be inundated, has recently been purchased by the EPA for a National Park. Apart from the previously identified issues, this last issue, above all, suggests that the Mt. Douglas site is not suitable for a dam development
Ecosystem-based assessment and management of marine and estuarine systems at the Queensland Nickel Yabulu Refinery, Townsville
Queensland Nickel Pty Ltd (QNPL) operate the Yabulu Refinery, located on a 2464 hectare land holding on the\ud
north Queensland tropical coast adjacent to Halifax Bay, approximately 30 km north west of Townsville. The\ud
coastal fringe separating the refinery area from the bay consists of mangrove areas, marshes and sand dunes. Since 1975, excess wastewaters from the refinery have been intermittently discharged via an ocean outfall pipeline extending 1.8 km into Halifax Bay. Since 1997, QNPL have completed a comprehensive Environmental Assessment and Management (EA&M) Program which includes the monitoring of the health of several aquatic ecosystems by considering both ecological and physio-chemical indicators of environmental quality. In undertaking the program, QNPL aim to achieve best management practice by understanding the\ud
impacts of the Yabulu refinery on its local environment and managing the environmental impacts appropriately. Results of the EA&M Program to date have identified impacts to Halifax Bay due to the ocean discharge of wastewaters and impacts to estuary ecosystems due to changes in hydrology. Monitoring of ecosystem health in Halifax Bay has found that despite ocean discharge practices, no appreciable impact on ecosystem health measures can be determined nor are elevated levels of contaminants found in fauna tissue samples of biota encrusted around the discharge pylon. Monitoring of estuaries within the coastal fringe did, however, identify that ecosystem health had been affected by refinery activities. The monitoring results indicated that impacts were due to changes in hydrologic conditions such as channel morphology. Remedial works to minimise and\ud
remove hydrologic changes are addressing these impacts. This paper describes the EA&M Program and its incorporation into both the strategic and day-to-day environmental planning and management of the refinery operations. In doing so, the paper will discuss how QNPL plan to manage their operations using information gathered from the annual ecological assessment program, environmental assessment programs and stakeholder input
Identifying the land-based sources of suspended sediments, nutrients and pesticides discharged to the Great Barrier Reef from the Tully–Murray Basin, Queensland, Australia
To assist in the development of the Tully Water Quality Improvement Plan, a subcatchment water quality
monitoring program was undertaken to identify the pollutants of concern and their land-based sources. Monitoring of suspended sediments, nutrients and pesticides in subcatchment waterways was conducted during the 2005–06 and 2006–07 wet seasons, which both had above average annual flows.We found distinct water quality signals from the basin’s major land uses (forest, grazing, urban, sugarcane and banana cultivation), except for suspended sediment concentrations, which were low across all land uses when compared with neighbouring river catchments. This reflects the high ground cover of the basin and the location of intensive agriculture on low sloping areas of the floodplain, minimising the potential for erosion.
Nitrate concentrations were elevated in streams draining sugarcane, indicating fertiliser export from intensive agricultural landscapes. Residues of the herbicides diuron and atrazine were detected at sites draining sugarcane, and on occasion exceeded national ecological protection trigger values, which highlights a potential threat to downstream wetlands of recognised national significance. Herbicides were also detectable offshore in flood plumes of the Tully–Murray Rivers, with some concentrations of diuron above lowest observable effect concentrations for specific species of seagrass and corals. Run-off of nitrate and diuron were identified as key water quality issues in the Tully–Murray basin