Leo Duivenvoorden - Academia.edu (original) (raw)

Papers by Leo Duivenvoorden

River Research and Applications, 2008

Aquatic Botany, 1987

ABSTRACT A centrifugation method to remove the surface water from five species of aquatic macroph... more ABSTRACT A centrifugation method to remove the surface water from five species of aquatic macrophytes of various morphologies is described and compared with the standard blotting method. The centrifugation method is up to twice as fast and up to three times more accurate than the blotting method. It works particularly well will plants of complex morphology and is less damaging to delicate plants than the blotting method. Errors in fresh weight determination between workers are also eliminated. Repeated centrifugation of plants, at 3-day intervals, was no more deleterious to their growth than the blotting method.

Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering, Jan 16, 2016

Acid-mine drainage (AMD) into the Dee River from the historic gold and copper mine in Mount Morga... more Acid-mine drainage (AMD) into the Dee River from the historic gold and copper mine in Mount Morgan, Queensland (Australia) has been of concern to farmers in the area since 1925. This study sought to determine the levels of AMD-related metals and sulfur in agricultural produce grown near the mine-impacted Dee River, compare these with similar produce grown in reference fields (which had no known AMD influence), and assess any potential health risk using relevant Australian or US guidelines. Analyses of lucerne (Medicago sativa; also known as alfalfa) from five Dee fields showed the following average concentrations (mg/kg dry basis): Cd < 1, Cu 11, Fe 106, Mn 52, Pb < 5, Zn 25 and S 3934; similar levels were found in lucerne hay (used as cattle feed) from two Dee fields. All lucerne and lucerne hay data were generally comparable with levels found in the lucerne reference fields, suggesting no AMD influence; the levels were within the US National Research Council (US NRC) guideli...

Journal of Environmental Science and Health, Part A, 2015

This study investigated the influence of acid-mine drainage (AMD) from the historic gold and copp... more This study investigated the influence of acid-mine drainage (AMD) from the historic gold and copper mine in Mount Morgan, Queensland (Australia) on Dee River sediments and adjacent agricultural soils during pre- and post-acid flows and the speciation of metals in these sediments and soils. This was done to assess the potential bioavailability of the metals and to provide baseline information for parallel research on the potential of the metals to enter agricultural produce. Sediments at site 5 (20 km downstream of the mine site) contained Cd, Cu, and Zn levels of 4.8, 2631, and 602 mg kg(-1), respectively, during low flow, and 2.6, 1835, and 756 mg kg(-1), respectively, post high or acid flow. Sediments at site 8A in the floodplain area (about 60 km downstream of the mine), showed Cd, Cu, and Zn levels of 0.6, 294, and 159 mg kg(-1), respectively, during low flow and 1.5, 689, and 295 mg kg(-1), respectively, post high (acid) flow. Sediment cores (18-cm long) from site 8A gave ratios of Cd, Cu and S concentration in the top slice (0-6 cm from riverbed surface) to their concentration in the deeper slice (12-18 cm) of 36, 9 and 40, respectively, indicating historical AMD contamination. Lead was not a serious AMD contaminant as its level varied less than two-fold within the core in all cases. Sulfur levels were consistently high (mean = 10267 mg kg(-1)) in the entire 12-cm core from site 7B and were about 10 times the surface (0-6 cm) levels from the other sites, suggesting possible geogenic S sources at this site. Mean Cu level was 1783 mg kg(-1) (range = 368-2510) in soils from the Dee River floodplain. BCR sequential extraction showed very similar average distribution of metals in the four fractions (F1 to F4) in sediments (from sites 5, 7B and 8A) and in the floodplain soils (site Dee P2). The sums of the acid-soluble (F1) and reducible (F2) fractions relative to the total metal content were Cd = 58%, Cu = 58%, Pb = 47% and Zn = 67% in sediments, and Cd = 67%, Cu = 63%, Pb = 47% and Zn = 58% in soils. Cu levels in these two most labile fractions alone exceeded the Australian sediment trigger value by an average factor of 9 (range = 3-23) in sediments, and the ecological investigation level for soils by an average factor of 12. The study demonstrated that AMD contamination spanned at least 80 km of the Dee River downstream of the mine and 30-cm depth of the riverbed and floodplains, with at least 50% of the total metal (particularly Cd, Cu and Zn) in the sediments and floodplain soils being potentially bioavailable to aquatic life and to the agricultural produce in the area.

Humic substances (HS) in naturally acidic waterways have been suggested to provide protection to ... more Humic substances (HS) in naturally acidic waterways have been suggested to provide protection to aquatic organisms exposed to low pH conditions. Despite this, little is known about the ability of HS to increase survivorship of freshwater organisms as pH decreases in waters of varying hardness. This study explored the ability of HS in the form of Aldrich humic acid (AHA) to increase survivorship of the freshwater shrimp (Caridina sp. D) at low pH in artificial soft (representative of naturally acidic environments) and hard waters (artificial and natural Dee River water). Freshwater shrimp were exposed to pH treatments ranging from pH 7 to pH 3.5, with and without 10 or 20 mg/L HS treatments. In low pH water, shrimp mortality was higher in artificial hard water (LC50 at pH 4.95) and natural hard water (LC50 at pH 4.74), compared with soft water (LC50 at pH 4.27). HS substantially decreased the threshold at which pH caused 50% mortality to the freshwater shrimp, with that threshold shi...

Ecotoxicology and Environmental Safety, 2014

Acid mine drainage (AMD) is a global problem leading to the acidification of freshwaters, as well... more Acid mine drainage (AMD) is a global problem leading to the acidification of freshwaters, as well as contamination by heavy metals. The ability of humic substances (HS) such as humic acid (HA) to decrease toxicity of heavy metals is widely known, whereas limited studies have examined the ability of HS to decrease toxicity linked with multiple stressors such as those associated with AMD. This study investigated the ability of HA to decrease acute toxicity defined as morbidity and ventilation frequency (measured via the time elapsed for ten operculum movements) in eastern rainbowfish (Melanotaenia splendida splendida) exposed to the multiple stressors of AMD-driven heavy metal concentrations, together with low pH. Water from the Mount Morgan open pit (a now closed gold and copper mine site), located at Mount Morgan, Central Queensland, Australia, was used as the AMD source. Fish were exposed to zero per cent (pH 7.3), two per cent (pH 6.7), three per cent (pH 5.7) and four per cent (pH 4.6) AMD in the presence of 0, 10 and 20mg/L Aldrich Humic Acid (AHA) over 96h. HA was shown to significantly decrease the acute toxicity of AMD and its adverse effects on ventilation frequency. These results are important in showing that HA can influence toxicity of metal mixtures and low pH, thus indicating a potential role for HA in decreasing toxicity of multiple environmental stressors more widely, and possible value as a rehabilitation aid.

Marine and Freshwater Research, 2015

ABSTRACT Adverse impacts of acidification on aquatic biota have been observed worldwide, however,... more ABSTRACT Adverse impacts of acidification on aquatic biota have been observed worldwide, however, most reports are based on freshwaters acidified from anthropogenic means. By contrast, naturally low pH values may not affect biota within naturally acidic freshwaters. This field study provides information on the water quality, macroinvertebrate and fish communities in little-studied, naturally acidic wallum streams, in Central Queensland, Australia. Mid-range pH sites (pH 5-6) were compared with low pH sites (pH 5-3.8) to investigate the effect of pH and other key water quality variables on these communities. Field data indicated that pH had less of an effect in these systems in terms of biotic changes compared with other water quality variables, with dissolved oxygen (% saturation) identified as the key driver for changes in macroinvertebrate composition. Fish were present at all sites, including those with pH <4. Several possible explanations for this lack of pH effect are discussed. These results provide support for the reduced importance of acidity, relative to other water quality parameters, in naturally acidic waters. The work also provides baseline data on the biota of little-studied wallum streams.

ABSTRACT Community awareness of the sustainable use of land, water and vegetation resources is in... more ABSTRACT Community awareness of the sustainable use of land, water and vegetation resources is increasing. The sustainable use of these resources is pivotal to sustainable farming systems. However, techniques for monitoring the sustainable management of these resources are poorly understood and untested. We propose a framework to benchmark and monitor resources in the grains industry. Eight steps are listed below to achieve these objectives: (i) define industry issues; (ii) identify the issues through growers, stakeholder and community consultation; (iii) identify indicators (measurable attributes, properties or characteristics) of sustainability through consultation with growers, stakeholders, experts and community members, relating to: crop productivity; resource maintenance/enhancement; biodiversity; economic viability; community viability; and institutional structure; (iv) develop and use selection criteria to select indicators that consider: responsiveness to change; ease of capture; community acceptance and involvement; interpretation; measurement error; stability, frequency and cost of measurement; spatial scale issues; and mapping capability in space and through time. The appropriateness of indicators can be evaluated using a decision making system such as a multiobjective decision support system (MO-DSS, a method to assist in decision making from multiple and conflicting objectives); (v) involve stakeholders and the community in the definition of goals and setting benchmarking and monitoring targets for sustainable farming; (vi) take preventive and corrective/remedial action; (vii) evaluate effectiveness of actions taken; and (viii) revise indicators as part of a continual improvement principle designed to achieve best management practice for sustainable farming systems. The major recommendations are to: (i) implement the framework for resources (land, water and vegetation, economic, community and institution) benchmarking and monitoring, and integrate this process with current activities so that awareness, implementation and evolution of sustainable resource management practices become normal practice in the grains industry; (ii) empower the grains industry to take the lead by using relevant sustainability indicators to benchmark and monitor resources; (iii) adopt a collaborative approach by involving various industry, community, catchment management and government agency groups to minimise implementation time. Monitoring programs such as Waterwatch, Soilcheck, Grasscheck and Topcrop should be utilised; (iv) encourage the adoption of a decision making system by growers and industry representatives as a participatory decision and evaluation process. Widespread use of sustainability indicators would assist in validating and refining these indicators and evaluating sustainable farming systems. The indicators could also assist in evaluating best management practices for the grains industry.

Toxicon, 2006

Scant information is available regarding the bioaccumulation of cylindrospermopsin (CYN) in aquat... more Scant information is available regarding the bioaccumulation of cylindrospermopsin (CYN) in aquatic organisms, particularly in invertebrates. This study examined toxin bioconcentration and bioaccumulation in the aquatic snail, Melanoides tuberculata, following exposure to freeze-thawed whole cell extracts and a live Cylindrospermopsis raciborskii culture containing CYN. Both bioconcentration and bioaccumulation were evident, but exposure to toxin in the freeze-thawed solutions resulted in minor tissue contamination compared with that resulting from live C. raciborskii exposure. Thus, whilst CYN uptake resulted from both extracellular and intracellular exposures, the availability of intracellular toxin was critical in affecting tissue CYN values. M. tuberculata did not bioconcentrate CYN into the shell. Bioaccumulation of the analog deoxy-CYN was also recorded. Knowledge of intracellular toxin concentrations may be critical in evaluating the bioaccumulation, ecological and human health risks associated with contaminated systems.

Marine Pollution Bulletin, 2005

Port Curtis is one of Australia&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;a... more Port Curtis is one of Australia&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s leading ports for which substantial industrial expansion is proposed over the next decade. However, there has been little attempt to date to assess the extent of contamination in waters, sediments and biota or to characterize the potential impacts of contaminants on aquatic biota. Contaminants of potential concern to biota and human health were investigated in the Port Curtis estuary using a screening-level risk assessment approach. Dissolved metal concentrations in waters were below [ANZECC/ARMCANZ, 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Vol. 1. The Guidelines, Australian and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand] trigger values, suggesting low risk of these contaminants. In sediments, arsenic, nickel and chromium concentrations exceeded interim sediment quality guidelines-low (ISQG-low), but were also high in the reference zone suggesting a natural origin. Historical data on naphthalene in Harbour sediments showed that it was also of potential concern. Bioaccumulation of contaminants in a range of biota was also used as an indicator of contaminant exposure. Biota were generally enriched in metals and tributyltin, which was also elevated in water and sediments. Although not unique to Port Curtis, mercury in barramundi was identified as a potential risk to human health.

Marine and Freshwater Research, 2002

Marine and Freshwater Research, 1988

ABSTRACT Physical, chemical and biotic attributes of 16 lakes and ponds in the siliceous dunefiel... more ABSTRACT Physical, chemical and biotic attributes of 16 lakes and ponds in the siliceous dunefields of Cape Flattery, in the humid tropics of Australia, have been investigated. The dune lakes are similar to those of dunefields in south-eastern Queensland, with very low to low conductivity (62-338 µS cm-1), low pH (3.9-6.8), and low to high humic content (gilvin 0.0-31.0 g440 m-1). These lakes are apparently not perched above the local water table. The ionic compositions of all lakes were very similar, with NaCl predominating and with very low concentrations of Mg, Ca, K, and SO4. Bicarbonate was absent or negligible in most lakes. The oligotrophic lakes are characterized by a desmid-diatom limnetic plankton of moderate diversity (12-35 species per lake). Of 144 taxa of phytoplankton recognized, 58% were desmids and 15% diatoms. The zooplankton was of low diversity and dominated by Calamoecia ultima. Twenty-nine species of aquatic macrophytes and 11 species of fish were recorded. Freshwater turtles (possibly Chelodina rugosa Ogilby), and the estuarine crocodile, Crocodylus porosus Schneider, were recorded from some lakes. Principal component analysis of chemical data distinguished three groups of lakes: a series of humic-stained ponds and lakes, a group of clear-water lakes with little or no humic staining, and a former barrier lagoon. Cluster analysis of the phytoplankton flora consistently segregated the clear-water lakes from humic-stained lakes but, in general, concordance of chemical, physiographic and biotic characteristics was poor. Existing classification schemes for Australian dune lakes, based on similar sets of physiographic, chemical and biotic data, do not cater well for the Cape Flattery lakes. A more useful classification may derive from consideration of the hydrological processes influencing their water balance and chemical characteristics.

Marine and Freshwater Research, 1996

ABSTRACT

Limnologica - Ecology and Management of Inland Waters, 2014

ABSTRACT Acidification of freshwaters via anthropogenic means is a global problem. Decreases in p... more ABSTRACT Acidification of freshwaters via anthropogenic means is a global problem. Decreases in pH in these systems have devastating effects on macroinvertebrate fauna especially Ephemeropterans. However, fauna in naturally acidic waters with high concentrations of humic substances (HS) appear to be less affected by acidification. This study investigated the ability of HS to decrease toxicity of low pH to mayflies (Atalophlebia spp.) in both hard and soft water environments. Laboratory trialling with both hard and soft water was conducted to represent water chemistries commonly associated with anthropogenic and naturally acidic freshwaters. Mayflies were exposed to decreases in pH between 7 (control) and 3.5 in the presence of 0, 10 and 20 mg/L HS (Aldrich humic acid). HS increased mayfly survival by up to 45% in soft water and up to 39% in hard water. HS were also shown to increase 96 hour LC50 values in both soft (4.29, 0 mg/L; 3.99, 10 mg/L and 3.97, 20 mg/L) and hard water (4.58, 0 mg/L; 4.22, 10 mg/L and 4.07, 20 mg/L). The results of this study are important in showing that HS can influence the toxicity of low pH environments; thus providing insight into why contrasting effects on biota are recorded from naturally acidic compared with anthropogenically-acidified environments

Lakes and Reservoirs: Research and Management, 2005

ABSTRACT Toxins produced by cyanoprokaryotes are a key issue in aquatic management because of the... more ABSTRACT Toxins produced by cyanoprokaryotes are a key issue in aquatic management because of their potential to exert adverse effects on humans and aquatic biota. The information gap regarding bioaccumulation and biomagnification processes associated with cyanotoxins, however, has resulted in inadequacies in the management and maintenance of biological diversity in lakes and reservoirs affected by toxic cyanoprokaryote blooms. This paper examines the potential for, and effects of, bioaccumulation of two common cyanotoxins, microcystin and cylindrospermopsin, in aquatic organisms. The factors influencing cyanotoxin bioavailability are discussed in the context of the challenges associated with understanding and managing toxin accumulation. Based on the characteristics of cyanotoxin bioavailability, exposure and uptake routes, a theoretical, predictive model for cyanotoxin bioaccumulation is proposed. Key concepts include monitoring changes in toxin availability throughout the progression of a toxic bloom and the prediction of ecological effects based on internal tissue concentrations. The model explores the minimum requirements that managers must undertake in order to properly assess bioaccumulation risk in terms of frequency of toxin testing, toxin fraction determination and assessment of aquatic organisms.

Hydrobiologia, 2000

Algal assemblages and their respective niches are analysed for a large riverine impoundment in se... more Algal assemblages and their respective niches are analysed for a large riverine impoundment in semi-arid Australia. The extreme variability of the flow regime and the extensive period of low or no flow produced conditions including prolonged stratification akin to those of a lake during the dry season. Hierarchical agglomerative clustering of phytoplankton data and comparison with a principal component analysis