Change in zooxanthellae and mucocyte tissue density as an adaptive response to environmental stress by the coral, <Emphasis Type="Italic">Montastraea annularis</Emphasis>

Results from controlled in situ experimentation conducted on the leeward reef tract of Curaçao, Netherlands Antilles, indicate that the coral Montastraea annularis exhibits a complex, yet consistent, cellular response to increasing sea surface temperature (SST) and decreasing irradiance. This was determined by simultaneously quantifying and tracking the tissue density of zooxanthellae and mucocytes using a novel technique that integrates the lectin histochemical stain wheat germ agglutinin (WGA) with high-resolution (200 nm) optical epifluorescence microscopy. Coral colonies growing at 6-m water depth (WD) and an irradiance of 100.2 ± 6.5 μmol m^?2 s^?1 were treated with a shading experiment for 11 days that reduced irradiance to 34.9 ± 6.6, 72.0 ± 7.0 and 90.1 ± 4.2 μmol m^?2 s^?1, respectively. While a significant decrease in the density of both zooxanthellae and mucocytes were observed at all shade levels, the largest reduction occurred between the natural non-shaded control (44,298 ± 3,242 zooxanthellae cm^?2; 4,853 ± 346 mucocytes cm^?2) and the highest shading level (13,982 ± 1,961 zooxanthallae cm^?2; 2,544 ± 372.9 mucocytes cm^?2). Colonies were also sampled during a seasonal increase in SST of 1.5°C, where the density of zooxanthellae was significantly lower (from 54,710 ± 1,755 to 34,322 ± 2,894 cells cm^?2) and the density of mucocytes was significantly higher (from 6,100 ± 304 to 29,658 ± 3,937 cells cm^?2). These observations of coral cellular response to environmental change provide evidence to support new hypotheses for coral survival and the complex role played by mucus in feeding, microbial associations and resilience to increasing SST.     

White blood cell sister chromatid exchange among a sample of Thai subjects exposed to lead: Lead-induced genotoxicity

Epidemiological and experimental studies indicated that inorganic lead compounds are associated with increased risks of tumorigenesis. This study was aimed at determination for sister chromatid exchange (SCE), a marker for genotoxicity with correlation to lead blood levels in Thai exposed subjects. A total of 32 police (all males) were included into this study. The average (mean ± SD) blood lead in these police was 2.1 ± 1 µmol L^?1. The average SCE among the police with high blood lead was significant higher than those with low metal exposure. Data suggest that cytogenetic response to Pb is significantly different between the subjects with high versus low lead exposure. High exposure to lead seems related to high chromosome aberrations.     

Evidence of new particle formation during post monsoon season over a high-altitude site of the Western Ghats,India

The formation of ultrafine particles, their growth, and associated characteristic features has been studied during new particle formation events over a high-altitude station of the Western Ghats during the 2014 post-monsoon season. Most of the events were observed during noon time where particle bursts in the nucleation-mode size range from 5 to 25 nm followed by sustained growth in size. This phenomenon persists for ～4–8 h with a growth rate of 1–2 nm h^–1. Peak concentrations of nucleation-mode particles during the event generally vary from 2300 to 5000 cm^–3. The mean growth rate is 1.4 ± 0.42 nm h^–1, particle formation rate is 1.14 ± 0.22 cm^–3 s^–1, coagulation sink is 0.35 ± 0.22 cm^–3 s^–1, and condensational sink is 15.4 ± 2.6?×?10^–3 s^–1. All these values are comparable with earlier results from Indian region. Comparison of size-segregated particle number concentration during days of new particle formation events and those without new particle formation were carried out showing a distinct variation in nucleation and Aitken mode with least variability associated with the accumulation mode.     

Effect of waterborne boron and molybdenum on survival,growth and feed intake of Indian major carp,Cirrhinus mrigala (Hamilton)

The effect of either boron (B) or molybdenum (Mo) on survival, growth and feed intake of Indian major carp, Cirrhinus mrigala (Hamilton), advanced fry was studied in two separate experiments. Survival rates of C. mrigala fry (2.78±0.14 g) following 50 days’ exposure to B at 0.01 (control), 0.5, 1.0, 2.0, 4.0 and 8.0 mg·L ^?1 were 100% at all concentrations except 8.0 mg·L ^?1 where the survival rate 87.5±7.5%. We observed 100% survival of mrigala fry at all concentrations of Mo, 0.02 (control), 0.5, 1.0, 2.0, 4.0 and 8.0 mg·L ^?1. Both B and Mo at 0.5 mg·L ^?1 showed significantly (p<0.05) higher growth of the fish compared with control and other concentrations. B exposure at 1.0, 2.0 and 4.0 mg·L ^?1 had no significant effect on growth rate, whereas at 8.0 mg B·L ^?1 growth of the fish almost ceased. Mo exposure at 1.0, 2.0, 4.0 and 8.0 mg·L ^?1 caused no significant effect on growth rate of the fish compared to control. Both B and Mo at all concentrations had no significant effect on feed intake of the fish compared with control, except at the highest concentration of boron (8.0 mg·L ^?1).     

Organic compounds in water extracts of coal: links to Balkan endemic nephropathy

The Pliocene lignite hypothesis is an environmental hypothesis that has been proposed to explain the etiology of Balkan endemic nephropathy (BEN). Aqueous leaching experiments were conducted on a variety of coal samples in order to simulate groundwater leaching of organic compounds, and to further test the role of the Pliocene lignite hypothesis in the etiology of BEN. Experiments were performed on lignite coal samples from endemic BEN areas in Romania and Serbia, and lignite and bituminous coals from nonendemic regions in Romania and the USA. Room temperature, hot water bath, and Soxhlet aqueous extraction experiments were conducted between 25 and 80 °C, and from 5 to 128 days in duration. A greater number of organic compounds and in higher concentrations were present in all three types of leaching experiments involving endemic area Pliocene lignite samples compared to all other coals examined. A BEN causing molecule or molecules may be among phenols, PAHs, benzenes, and/or lignin degradation compounds. The proposed transport pathway of the Pliocene lignite hypothesis for organic compound exposure from endemic area Pliocene lignite coals to well and spring drinking water, is likely. Aromatic compounds leached by groundwater from Pliocene lignite deposits in the vicinity of endemic BEN areas may play a role in the etiology of the disease. A better understanding of organic compounds leached by groundwater from Pliocene lignite deposits may potentially lead to the identification and implementation of effective strategies for the prevention of exposure to the causative agent(s) for BEN, and in turn, prevention of the disease.     

Cadmium accumulation by green algae Cladophora glomerata (L.) Kutz. (Chlorophyta) in presence of Nile tilapia Oreochromis niloticus (L.)

Accumulation of metals by aquatic organisms is mostly affected by other biological components in environments. In this study, cadmium (Cd) accumulation in green algae, Cladophora glomerata (L.) Kutz., exposed to 0.1 and 1.0 mg L^?1 of Cd for 15 and 30 days was examined in laboratory conditions in the presence of Nile tilapia Oreochromis niloticus (L.). The green algae C. glomerata accumulated Cd concentrations as 690 ± 70 and 3430 ± 470 mg kg^?1 on day 15, and 1130 ± 180 and 6830 ± 1540 mg kg^?1 on day 30. There were significant increases (p < 0.05) in metal accumulation by green algae as the exposure time and metal concentration increased. The results also indicated that the presence of Nile tilapia in the medium led to a significant Cd accumulation in the green algae compared to control (p < 0.05).     

Release of beryllium from mineral ores in artificial lung and skin surface fluids

Exposure to some manufactured beryllium compounds via skin contact or inhalation can cause sensitization. A portion of sensitized persons who inhale beryllium may develop chronic beryllium disease (CBD). Little is understood about exposures to naturally occurring beryllium minerals. The purpose of this study was to assess the bioaccessibility of beryllium from bertrandite ore. Dissolution of bertrandite from two mine pits (Monitor and Blue Chalk) was evaluated for both the dermal and inhalation exposure pathways by determining bioaccessibility in artificial sweat (pH 5.3 and pH 6.5), airway lining fluid (SUF, pH 7.3), and alveolar macrophage phagolysosomal fluid (PSF, pH 4.5). Significantly more beryllium was released from Monitor pit ore than Blue Chalk pit ore in artificial sweat buffered to pH 5.3 (0.88 ± 0.01% vs. 0.36 ± 0.00%) and pH 6.5 (0.09 ± 0.00% vs. 0.03 ± 0.01%). Rates of beryllium released from the ores in artificial sweat were faster than previously measured for manufactured forms of beryllium (e.g., beryllium oxide), known to induce sensitization in mice. In SUF, levels of beryllium were below the analytical limit of detection. In PSF, beryllium dissolution was biphasic (initial rapid diffusion followed by latter slower surface reactions). During the latter phase, dissolution half-times were 1,400 to 2,000 days, and rate constants were ~7 × 10⁻¹⁰ g/(cm²·day), indicating that bertrandite is persistent in the lung. These data indicate that it is prudent to control skin and inhalation exposures to bertrandite dusts.     

Polychlorinated biphenyls and organochlorine pesticides in amniotic fluids of pregnant women in south-central Turkey†

The concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in amniotic fluid of 200 pregnant women from the Cukurova region of Turkey. The concentrations of OCPs [hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), dichlorodiphenyl trichloroethane (p,p′-DDT), and various metabolites], and different PCB congeners (28, 52, 101, 118, 138, 153, 180) were determined by gas chromatography with electron capture detection as follows: HCB 6.6 ± 4.7, ΣHCH 21.6 ± 14.2, ΣDDT 12.5 ± 7.5, and ΣPCBs 74.0 ± 54 ng mL^?1. Correlations of maternal or gestational age and levels of OCPs and PCBs were not significant. The levels of these organochlorine compounds (OCs) were below detection limit for 5% of the samples, 80% contained more than one OC. This study illustrates that prenatal exposure of a fetus to OCs is prevalent in the Cukurova region.     

Biological effects of water soluble fraction of crude oil on the Arctic sea ice amphipod Gammarus wilkitzkii

With increasing petroleum related activity in the Barents Sea and the subsequent risk of accidents, there is a demand for knowledge about the effect of oil pollution in Arctic ecosystems. In the present study, the sea ice amphipod Gammarus wilkitzkii was exposed to a water soluble fraction (WSF) of oil in two experiments, using a rock column system. First, three groups of adult females were exposed for 36 days for control (n=9), low dose (n=10) (initial and final oil concentration: 14, 115 and 120 μ g/l) and high dose (n=10) (initial and final oil concentration: 78, 764 and 395 μ g/l). Total oxyradical scavenging capacity (TOSC), malondialdehyde (MDA), catalase activity (CAT), respiration rate and mortality were measured. In the second experiment, moulting rate was measured in immature individuals of two groups, control (n=10) and exposed (n = 20), over 113 days. No mortality was observed in either of the experiments. There was a dose-related significant increase in respiration rate (40.69 (±22.82), 55.63 (±20.98), 94.57 (±22.80)) mg O₂ h^?1g ww^?1 in control, low dose and high dose, respectively. A higher MDA level was detected in the low dose group (25.04 (±6.00) nmol g^?1 of tissue) compared to both control (20.44 (±2.62) nmol g^?1 of tissue) and high dose groups (20.93 (±4.79) nmol g^?1 of tissue). Likewise, the low dose group had the highest value of TOSC towards hydroxyl (727.74 (±475.58), 1157.58 (±278.62), 1067.30 (±369.22) TOSC unit value mg^?1 of protein for control, low and high dose, respectively). Although no difference in the catalase activity between control and exposed groups was detected, higher activity was measured at 0 °C (average: 248 μ mol^?1 min^?1 mg^?1 of protein) than at the standard temperature for catalase measurement of 25 °C (average: 140 μ mol^?1 min^?1 mg^?1 of protein), indicating a need to optimise the standard operational procedure when working with Arctic organisms. No effect of WSF exposure on moulting rate was detected. In conclusion, little mortality was observed during the experiments, indicating some degree of tolerance levels. However, the biomarker results indicated sub-lethal effects in G. wilkitzkii after exposure to WSF.     

Exposure assessment,chemical characterization and source identification of PM2.5 for school children and industrial downwind residents in Guangzhou,China

To assess the exposure doses of PM_2.5 and to investigate its chemical components for the subpopulation (i.e., school children and industrial downwind residents), simultaneous sampling of indoor and outdoor PM_2.5 was conducted at an elementary school close to traffic arteries and a residence located in the downwind area of a steel plant in metropolitan Guangzhou in 2010. Chemical components, i.e., organic carbon, elemental carbon and 6 water soluble ions were analyzed in PM_2.5. A survey was also conducted to investigate the time-activity patterns of the school children and the industrial downwind residents. Indoor and outdoor PM_2.5 were 63.2 ± 20.1 and (76.7 ± 35.8) μg/m³ at the school, and 118.8 ± 44.7 and 125.7 ± 57.1 μg/m³ in the community, respectively. Indoor PM_2.5 was found to be highly related to outdoor sources, and stationary sources were the significant contributors to PM_2.5 at both sites. The daily average doses of PM_2.5 for the school children at the school (D _children) and the industrial downwind residents in the community (D _residents) were (7.6 ± 1.9) and (36.1 ± 36.8) μg/kg-day, respectively. The daily average doses of particulate organic mass and SO₄ ^2? were the two most abundant chemical components in PM_2.5. PM_2.5 exposure for the school children was contributed by indoor and outdoor environments by 48.8 and 51.2 %, respectively; for the industrial downwind residents, the contributions were 66.0 and 34.0 %, respectively. Age and body weight were significantly and negatively correlated with D _children, while age, body weight and education level were significantly and negatively correlated with D _residents; gender was not a significant factor at both cases.     

Direct and indirect effects of pesticides on a benthic grazer during its life cycle

Background

Macroinvertebrates in aquatic ecosystems are repeatedly exposed to pesticides during their life cycle. Effects of consecutive exposure during different life stages and possible synergistic effects are not addressed in the standardized hazard assessment. The present study investigated two environmentally relevant exposure scenarios in batch (microcosm) and artificial indoor stream (mesocosm) experiments using the larvae of the mayfly Rhithrogena semicolorata (grazer) and natural aufwuchs. Grazers were analysed regarding growth, physiological condition, and drift behaviour, while the aufwuchs was analysed in terms of biomass using the particulate organic carbon as well as the chlorophyll a content. The aim was to reveal direct and indirect effects of an herbicide exposure during autumn on juvenile grazers and an insecticide exposure during spring on semi-juvenile grazers.

Results

Direct and indirect effects were found in both exposure scenarios at environmentally relevant concentrations. In the herbicide exposure scenario with terbutryn, clear direct effects on the aufwuchs community with a LOEC of 0.38 µg L^?1 were found. Effect levels of grazers due to indirect effects were equal, with the overnight drift being the most sensitive grazer endpoint. In the insecticide exposure scenario, clear lethal and sub lethal effects of lambda-cyhalothrin were evident. Derived LC₅₀ values for the artificial indoor stream and batch experiment were 2.42 µg g^?1 OC (69 days) and 1.2 µg g^?1 OC (28 days), respectively. Sub lethal effects in terms of increased drift as well-reduced growth and triglyceride levels were found at concentrations of 1.4 and 0.09 µg g^?1 OC (LOECs). These results were confirmed by the batch experiment, which revealed effect values in the similar range. Finally, a clear indirect effect of the insecticide on the aufwuchs was evident in the batch experiment with an LOEC at 0.9 µg g^?1 OC.

Conclusion

Toxicity Exposure Ratios calculated with the derived effect values indicate a risk for the investigated grazer by both pesticides. Moreover, observed indirect effects during the herbicide exposure seem to be able to affect the grazers during a second exposure with an insecticide, due to reduced physiological conditions. We suggest further research with time-shifted exposure scenarios to gain a better understanding of the complex interactions of pesticides with the life cycle and the food webs of macroinvertebrates.

     

Antioxidant rich diet supplements (Spirulina and tamarind fruit pulp) mitigate hematological disorders in fluoride exposed mice

The effect of antioxidant rich diet supplements of Spirulina and tamarind fruit pulp at 230 mg kg^?1 body weight, separately as well as in combination, on various hematological parameters of Swiss albino mice exposed to fluoride for seven days at daily doses of 190 mg kg^?1 body weight and for 90 days at daily doses of 94 mg kg^?1 body weight is reported. Compared with controls, fluoride exposure decreased erythrocyte (12%–18%), leukocyte (16%) and platelet counts (7%, only for short-term exposure), hemoglobin (2%–17%) and packed cell volume (2%–14%) in Swiss albino mice reared on standard feed but these were altered little in the diet supplement groups. Fluoride exposure decreased lymphocytes in both standard feed (16%–21%) and diet supplement groups (5%–19%, but only after long-term exposure). Fluoride withdrawal led to recovery of the post-treated mice from long-term exposure. Spirulina alone and also in combination with tamarind fruit pulp was found more effective than tamarind alone in reducing hematological disorders in fluoride treated mice.     

Ecology of juvenile hawksbills (Eretmochelys imbricata) at Buck Island Reef National Monument, US Virgin Islands

Surveys of juvenile hawksbills around Buck Island Reef National Monument, US Virgin Islands from 1994 to 1999 revealed distributional patterns and resulted in a total of 75 individual hawksbill captures from all years; turtles ranged from 23.2 to 77.7 cm curved carapace length (CCL; mean 42.1 ± 12.3 cm SD). Juveniles concentrated where Zoanthid cover was highest. Length of time between recaptures, or presumed minimum site residency, ranged from 59 to 1,396 days (mean 620.8 ± 402.4 days SD). Growth rates for 23 juveniles ranged from 0.0 to 9.5 cm year^?1 (mean 4.1 ± 2.4 cm year^?1SD). Annual mean growth rates were non-monotonic, with the largest mean growth rate occurring in the 30–39 cm CCL size class. Gastric lavages indicated that Zoanthids were the primary food source for hawksbills. These results contribute to our understanding of juvenile hawksbill ecology and serve as a baseline for future studies or inventories of hawksbills in the Caribbean.     

Influence of a botanical pesticide,azadirachtin, on ultimobranchial gland of the freshwater catfish Heteropneustes fossilis

Freshwater catfish, Heteropneustes fossilis, were subjected to 42 mg L^?1 of azadirachtin for short-term exposure (96 h) and to 10.5 mg L^?1 for long-term exposure (28 days). Six fishes were sacrificed on each time interval from control and experimental groups after 24, 48, 72, and 96 h in the short-term exposure and after 7, 14, 21, and 28 days in the long-term experiment. The calcium regulating endocrine gland, viz. the ultimobranchial gland, was fixed for histological studies. Up to 72 h of azadirachtin treatment, there was no histological alteration in the UBG (ultimobranchial gland) of H. fossilis. After 96 h exposure, the ultimobranchial cells stain feebly and the nuclear volume of these cells were slightly decreased. No histological alterations have been observed in the UBG cells up to 14 days following azadirachtin exposure. After 21 days, the cytoplasm of ultimobranchial cells was feebly stained and the nuclear volume exhibits a decrease. The nuclear volume of these cells was further decreased and the gland shows vacuolization and degeneration at certain places after 28 days azadirachtin treatment. Hence, it can be concluded that azadirachtin severely affects the physiology of calcium homeostasis in H. fossilis. Therefore, the botanical pesticides should be used carefully near aquatic reservoirs.     

Seasonal concentrations of lead in outdoor and indoor dust and blood of children in Riyadh,Saudi Arabia

Because detrimental effects of exposure to lead (Pb) on human health have been observed, we previously investigated concentrations of Pb in water supplies and blood of adult residents of Riyadh, Saudi Arabia. The objectives of the present study were to: (1) examine seasonal rates of deposition of Pb in dust in several areas of Riyadh city, (2) measure concentrations of Pb in both outdoor and indoor dust, (3) compare concentrations of Pb in dust in Riyadh with those reported for other cities, and (4) quantify Pb in blood of children living in Riyadh. Mean, monthly deposition of PB in outdoor dust was 4.7 × 10¹ ± 3.6 tons km^?2, with a mean Pb concentration of 2.4 × 10² ± 4.4 × 10¹ μg/g. Mean, monthly deposition of Pb in indoor dust was 2.7 ± 0.70 tons km^?2, with a mean concentration of 2.9 × 10¹ ± 1.5 × 10¹ μg Pb/g. There was a significant (P < 0.01) correlation between concentrations of Pb in outdoor and indoor dust. There was no correlation between concentrations of Pb in indoor dust and that in blood of children of Riyadh, whereas there was a weakly significant (P < 0.05) correlation between concentrations of Pb in outdoor dust and that in blood of children. The mean (±SD) concentration of Pb in blood of children in Riyadh was 5.2 ± 1.7, with a range of 1.7–1.6 × 10¹ μg/dl. Concentrations of Pb in blood of 17.8 % of children in Riyadh were greater than 10 μg/dl, which is the CDC’s level of concern.     

Evaluation of rare earth elements in groundwater of Lagos and Ogun States,Southwest Nigeria

Rare earth elements in our environment are becoming important because of their utilization in permanent magnets, lamp phosphors, superconductors, rechargeable batteries, catalyst, ceramics and other applications. This study was conducted to evaluate the level of rare earth elements (REE) and the variability of their anomalous behavior in groundwater samples collected from Lagos and Ogun States, Southwest, Nigeria. REE concentrations were determined in 170 groundwater samples using inductively coupled plasma-mass spectrometry, while the physicochemical parameters were determined using standard methods. Lagos State groundwater is enriched with REE [sum REEs range (mean ± SD)]; [0.365–488 (69.5 ± 117)] µg L^?1 than Ogun State groundwater [sum REEs range (mean ± SD)]; [1.14–232 (22.6 ± 41.1)] µg L^?1. Boreholes are more enriched with REEs than wells. Significant (P < 0.05) positive correlation (R = Pearson) was recorded in Lagos State groundwater between sum REEs and Fe (R = 0.55). However, there were no significant correlations between sum REEs, pH (R = 0.073) and HCO₃ ^2? (R = 0.157) in Ogun State groundwater. Chondrite-normalized plot shows that Lagos groundwater exhibits positive Ce anomaly, while Ogun State groundwater does not. The source of REE in Lagos State may be from the ocean and leaching from wastes dumpsites, while the source in Ogun State groundwater may be from the rocks.     

Arsenic concentration in rice, fish, meat and vegetables in Cambodia: a preliminary risk assessment

To assess arsenic contaminations and its possible adverse health effects, food samples were collected from Kandal, Kratie and Kampong Cham in Cambodia. The highest and the lowest concentrations were observed in fish (mean 2,832 ng g^?1, ww) collected from Kandal province and cattle stomach (1.86 ± 1.10 ng g^?1, ww) collected from Kratie, respectively. The daily intake of arsenic via food consumption was 604, 9.70 and 136 μg day^?1 in Kandal, Kratie and Kampong Cham, respectively. The arsenic dietary intake in Kandal ranked No. 1 among all the 17 compared countries or regions. Fish consumption contributed the greatest proportion of total arsenic daily intake in Kandal (about 63.0 %) and Kampong Cham (about 69.8 %). It is revealed to be a much more important exposure pathway than drinking water for residents in Kampong Cham. The results of risk assessment suggested that the residents in Cambodia, particularly for people in Kandal province, suffer high public health risks due to consuming arsenic-contaminated food.     

Reproductive dynamics of the sea urchin Paracentrotus lividus on the Galicia coast (NW Spain): effects of habitat and population density

We studied the spatial variability in the size at first maturity and the reproductive cycle of Paracentrotus lividus in Galicia, contributing key information for the exploitation and management of this resource. The size at maturity varied between 20.4 (±1.2 SE) mm and 27.9 ± 1.2 mm and was smaller in areas of low population density where sea urchins do not form patches. Using a nonlinear model, we analysed the effect of depth, body size, sex and population density on the temporal pattern of the gonad index. The maximum and minimum indices were obtained at 4 m depth in the months before and after the spring spawning, respectively. The depth also affected the cycle phase, and the sea urchins at 4 m depth spawned 9.4 ± 3.0 days later than the sea urchins at 8 m depth and 20.5 ± 3.0 days later than those at 12 m depth. Moreover, the sea urchins living in patches showed a slight increase in gonad size as a consequence of the better-quality habitat. This shows that there is no intraspecific competition in this area despite the high population densities reached (18.5 kg m^?2).     

Responses of the earthworm Eisenia andrei exposed to sublethal aluminium levels in an artificial soil substrate

Industrial discharges of Al are increasingly common. In this study, the activities of three antioxidases, malondialdehyde (MDA) content and changes in coelomocytes were investigated in earthworms (Eisenia andrei) exposed to different concentrations of aluminium chloride (range 0–200 mg Al kg^?1 dry soil) in artificial soils for 32 days. Within the first 16 days of Al exposure, catalase activity was elevated in most treatments, while the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were inhibited in all treatments. After 16 days exposure, SOD and GSH-Px activities returned to normal at lower Al concentrations, but were still inhibited at higher concentrations, hence the inhibition of SOD and GSH-Px showed some exposure-level dependence during the late exposure phase. MDA content was significantly elevated from 16 days after initial exposure. Neutral Red retention time of coelomocytes decreased at the highest exposure concentrations after 32 days, and an increased proportion of cells showing membrane damage was also observed at this time using flow cytometry. We conclude that excessive Al in soils can cause oxidative stress and cell damage in earthworms. Hence, Al accumulation in the environment may present an ecological hazard through suppression of the important functions of earthworms in soil ecosystems.     

Home range of immature green turtles tracked at an offshore tropical reef using automated passive acoustic technology

Seventeen immature green turtles Chelonia mydas were tracked concurrently by automated ultrasonic receivers at a coral reef off North-Eastern Australia (September–December 2010, 16.4°S, 145.6°E). The majority (n = 11) were tracked for the entire 100-day study, the remainder for 23–85 days. Detection data aggregated at 30-min intervals produced median 6.5–35 daily locations for individual turtles. Home range areas (95 % utilisation distribution) were ≤1 km², $ {\bar{\text{x}}} $  ± SD = 0.74 km² ± 0.159. To the best of our knowledge, these are the first home range estimates for C. mydas foraging at offshore tropical reefs. The findings are important for conservation in revealing near-continuous presence of the same individuals within a small geographic area. Time between detections was very short (median <3 min) demonstrating passive ultrasonic technology can track multiple turtles in a foraging environment with higher temporal resolution than typically achieved by satellite tracking.