Effects of Habitat Fragmentation on the Reproductive Ecology of Four Plant Species in Mallee Woodland

Abstract: Habitat fragmentation has the potential to affect plant reproduction by changing the community of pollinators and natural enemies, the neighborhood of potential mates, the availability of resources, and microclimate. I examined the effect of habitat fragmentation on reproduction of four species found in mallee woodlands of central New South Wales, Australia: Acacia brachybotrya , Senna artemisioides , Eremophila glabra , and Dianella revoluta . At six sites I surveyed plants in a reserve and in a nearby linear strip of vegetation. Two additional sites were established in a large reserve. Many effects were apparent at the extreme end of fragmentation, revealed by two-way analysis of covariance comparing reserves and linear strips at each site. The nature of the response differed among species. Flower production was greater in most linear strip fragments for S. artemisioides and E. glabra . Fruit set efficiency was significantly greater in linear strips for S. artemisioides and significantly lower for A. brachybotrya , E. glabra , and D. revoluta . Fruit predation was lower in most linear strips for E. glabra . For A. brachybotrya , fruit predation was significantly lower in linear strips. The net effect of these changes was a significant increase in whole-plant seed production for S. artemisioides , a significant decrease in whole-plant seed production for A. brachybotrya and in whole-plant fruit production for D. revoluta , and no consistent effect on whole-plant fruit production for E. glabra . In contrast, the only pattern apparent when the effect of fragment size was considered over a range from linear strips <40 m wide to a reserve> 140,000 ha was a positive correlation between the fragment size and fruit-set efficiency of A. brachybotrya . These results suggest that habitat fragmentation can significantly alter important reproductive functions of species, by changing both the plant's physical environment and its interactions with animals.     

Effect of biosurfactants on crude oil desorption and mobilization in a soil system

Microbially produced biosurfactants were studied to enhance crude oil desorption and mobilization in model soil column systems. The ability of biosurfactants from Rhodococcus ruber to remove the oil from the soil core was 1.4-2.3 times greater than that of a synthetic surfactant of suitable properties, Tween 60. Biosurfactant-enhanced oil mobilization was temperature-related, and it was slower at 15 degrees C than at 22-28 degrees C. Mathematical modelling using a one-dimensional filtration model was applied to simulate the process of oil penetration through a soil column in the presence of (bio)surfactants. A strong positive correlation (R(2)=0.99) was found between surfactant penetration through oil-contaminated soil and oil removal activity. Biosurfactant was less adsorbed to soil components than synthetic surfactant, thus rapidly penetrating through the soil column and effectively removing 65-82% of crude oil. Chemical analysis showed that crude oil removed by biosurfactant contained a lower proportion of high-molecular-weight paraffins and asphaltenes, the most nonbiodegradable compounds, compared to initial oil composition. This result suggests that oil mobilized by biosurfactants could be easily biodegraded by soil bacteria. Rhodococcus biosurfactants can be used for in situ remediation of oil-contaminated soils.     

Protecting the planet and its people: how do interventions to promote environmental sustainability and occupational safety and health overlap?

Problem: The challenges of both occupational safety and health and environmental sustainability require large-scale behavior change for meaningful improvements to occur. Environmental sustainability, or the ‘green movement’ has received far more attention recently, and certain strategies and recommendations from interventions designed for promoting pro-environmental behaviors may inform efforts to intervene on critical behaviors for improving occupational safety and health. Method: A survey of the literature regarding behavioral interventions for both environmental sustainability and occupational safety and health was conducted. Several theoretical approaches are reviewed, and successful approaches from each domain are identified, as well as parallel challenges and points for crossover. Recommendations are provided for adapting environmental sustainability intervention approaches for occupational safety and health applications. Impact on Industry: Safety and health leaders may achieve sustainable improvements in worker safety and health by harnessing the momentum of the green movement and adapting successful intervention approaches from the environmental sustainability domain.     

Incident, accident, catastrophe: cyanide on the Danube

It has been described as the worst disaster since Chernobyl. In January 2000, a retaining wall failed at the Aurul gold processing plant in Romania, releasing a wave of cyanide and heavy metals that moved quickly from one river to the next through Romania, Hungary, the Federal Republic of Yugoslavia and Bulgaria, killing tens of thousands of fish and other forms of wildlife and poisoning drinking-water supplies. This paper examines how and why the chemical spill at Baia Mare occurred and how responses to it emerged from circumstances at the global, local and immediate levels. The spill demonstrates the importance of the flow of information in framing and interpreting disasters, suggesting that such an event can go unnoticed or be viewed as catastrophic, depending on the political, historical and personal struggles that lead to its publicity. The paper offers a framework for understanding why the spill was alternately perceived as an incident, an accident and a catastrophe based on changing perceptions of culpability.     

Measuring the environmental performance of IPPC industry: I. Devising a quantitative science-based and policy-weighted Environmental Emissions Index

This paper describes the derivation of an Environmental Emissions Index (EEI) intended to quantify the environmental performance of Integrated Pollution Prevention and Control (IPPC) installations and sectors. Characterisation and normalisation methods used in lifecycle analyses were applied to 20 routinely reported emissions parameters, pertaining to six environmental impact categories. Distance to policy targets for relevant emissions were used to weight impact categories, and link the EEI to policy priorities. Ireland and the EU15 were considered as scales of context. The European Pollutant Emission Register was a convenient source of normalisation data, but restricted the context of the EEI to industrial emissions, and distorted outputs. Using national and EU15 total loading estimates for normalisation resulted in an EEI that better reflected the relative contribution of reported emissions towards overall environmental pressures. Using Ireland's pharmaceutical sector as a case study indicated that weighting factors, and the toxicity range of NMVOC emissions, were the largest sources of EEI uncertainty. Through the integration of inventory data, scientific characterisation, and policy targets, the EEI translates reported emissions data from IPPC installations and sectors into a benchmark of environmental performance. It may be regarded as an evolving tool of potential utility to regulators and policy makers.     

Estimation of VOC emissions

Emissions of volatile organic compounds (VOCs) is a major concern for industry. In order to reduce these, and to apply prevention options, it is necessary to accurately quantify them. A reliable methodology for such quantification does not yet exist. This paper presents an overview of methods currently available, together with some shortcomings. It urges further work to develop reliable techniques, and suggests possible areas for future work.     

The role of male vs male interactions in maintaining population dialect structure

Summary Nonmigratory populations of Whitecrowned Sparrows in coastal California exhibit dialects in territorial male songs that are stable in space and time. By field playback experiments, we tested a prediction from the hypothesis that male aggressive interactions prohibit mixing of song dialects. Playback of the home dialect Clear song to territorial males singing the Clear dialect resulted in less response than that given to playback of the neighboring Buzzy dialect. Response to both Buzzy and Clear dialect songs by target Clear males, however, was greater than that given to the Bodega dialect recorded 55 km away (Figs. 2 and 3). We conclude that these results are consistent with the hypothesis that male-male aggressive interactions play an important role in reducing dialect mixing.     

Nucleic acid concentrations and enzyme activities as correlates of growth rate of the saithe Pollachius virens: growth-rate estimates of open-sea fish

The aim of this study was to estimate the growth rate of saithe, Pollachius virens L., in wild populations collected from around the Beryl Alpha oil platform in October 1988 and from Loch Ewe on the west coast of Scotland in August 1989, by comparing the concentrations of various growth-rate indicators in the white muscle with those of laboratory-maintained individuals of known growth rates. There were significant correlations between the individual growth rates of laboratory-maintained saithe and concentrations of white muscle RNA expressed as g RNA mg^-1 protein, mg RNA mg^-1 DNA and as mg RNA g^-1 muscle. Growth rate was also correlated with the activities of the enzymes citrate synthase, cytochrome oxidase and lactate dehydrogenase. RNA concentrations decreased with increasing body size, and weight-corrected estimates of RNA concentrations for a standard-sized individual were determined from the scaling relationships. RNA concentrations expressed in three different ways gave similar estimates of the growth rate for two samples of wild saithe, one from around an oil platform and the other from the west coast of Scotland. RNA concentrations were correlated with aerobic enzyme levels in oil-platform fish, although the growth rate estimates of the same wild fish were lower when expressed as a function of aerobic enzyme levels than when expressed as a function of lactate dehydrogenase concentration. It is concluded that the capacity for protein synthesis of white muscle expressed as RNA concentrations in relation to wet or dry weight may be used as an estimate of instantaneous growth rate and that additional confidence in such estimates may be gained from measurement of the levels of aerobic enzymes.