Impacts of experimental trampling on tall alpine herbfields and subalpine grasslands in the Australian Alps

The Australian Alps, which are of high conservation value, are popular summer bushwalking destinations. Experimental trampling trials using a standardized methodology were conducted to determine the resistance and resilience of the two common vegetation types: tall alpine herbfield and subalpine grasslands. Vegetation parameters were measured in lanes subject to control (no trampling), 30, 100, 200, 500 and 700 passes at five sites prior to trampling, immediately post trampling, 2 weeks, 6 weeks and 1 year post trampling. Vegetation height, cover of graminoids and herbs, as well as net species richness all declined with trampling, while litter cover increased. Thresholds for damage varied between the two communities and among the different vegetation parameters. The resistance indices for the two communities (number of passes resulting in 50% reduction in vegetation cover), however, were similar at around 440–450 passes indicating that these two communities are among the most resistant of the 19 alpine–subalpine communities that have been tested around the world, but only of moderate resistance compared to non-alpine communities. The two communities showed limited recovery with damage still evident 1 year post trampling. This indicates that they have only moderate tolerance to damage due to moderate resistance, but low resilience.     

Return to the River: Environmental Flow Policy in the United States and Canada1

Abstract: This paper provides an overview and summary of United States and Canadian federal, state, and provincial laws that offer some form of legal protection for environmental flows. Special attention is given to the new “second generation” law established in Texas and to ways western states are beginning to encourage transactions that help restore dewatered streams. Progress in the eastern states and some Canadian provinces to provide environmental flow protection is addressed. Based on this review, this paper presents recommended elements of a “model” environmental flow policy.     

Processing of poultry feathers by alkaline keratin hydrolyzing enzyme from Serratia sp. HPC 1383

The present study describes the production and characterization of a feather hydrolyzing enzyme by Serratia sp. HPC 1383 isolated from tannery sludge, which was identified by the ability to form clear zones around colonies on milk agar plates. The proteolytic activity was expressed in terms of the micromoles of tyrosine released from substrate casein per ml per min (U/mL min). Induction of the inoculum with protein was essential to stimulate higher activity of the enzyme, with 0.03% feathermeal in the inoculum resulting in increased enzyme activity (45 U/mL) that further increased to 90 U/mL when 3 d old inoculum was used. The highest enzyme activity, 130 U/mL, was observed in the presence of 0.2% yeast extract. The optimum assay temperature and pH for the enzyme were found to be 60 °C and 10.0, respectively. The enzyme had a half-life of 10 min at 60 °C, which improved slightly to 18 min in presence of 1 mM Ca²⁺. Inhibition of the enzyme by phenylmethyl sulfonyl fluoride (PMSF) indicated that the enzyme was a serine protease. The enzyme was also partially inhibited (39%) by the reducing agent β-mercaptoethanol and by divalent metal ions such as Zn²⁺ (41% inhibition). However, Ca²⁺ and Fe²⁺ resulted in increases in enzyme activity of 15% and 26%, respectively. The kinetic constants of the keratinase were found to be 3.84 μM (K_m) and 108.7 μM/mL min (V_max). These results suggest that this extracellular keratinase may be a useful alternative and eco-friendly route for handling the abundant amount of waste feathers or for applications in other industrial processes.     

Working safely with foreign contractors and personnel

Foreign companies and personnel are increasingly being employed for risky activities in process industry (Agro, Gas and Chemicals) in the north of the Netherlands. Against the backdrop of these developments, the need arose within the ‘VGM Noord-Nederland’ cooperation (health, safety and the environment in the Northern Netherlands) to further investigate experienced and detected problems, possible explanations, solutions and directions for preventing unsafe situations when working with foreign contractors and personnel. Because of little scientific information available on the topic, in autumn of 2004 an exploratory study was conducted into ‘working with foreign contractors and personnel’ in the process industry in the northern Netherlands under the auspices of VGM Noord-Nederland. In the course of the study, ten qualitative interviews were held with safety experts working at multinational companies in the agro, gas and chemical industry in the Northern Netherlands. The objective of the study was to gain sharper insight into the common problems and best practices experienced by these companies when working with foreign contractors and personnel in order to focus future joint activities towards these problematic areas. The study resulted in the identification of five problematic areas: communication, level of education, cultural differences, specific employment situations and cooperation between principal and contractor. All of these factors can be located within the ‘latent failure types’ or ‘basic risk factors’ described by the well known Tripod Model (i.e. Groeneweg, J., Lancioni, G.E., Metaal, N., 2002. Motivating for Safety, Leading by Example: moving from Compliance to Competence, Profshore Management Motivation Module, Stavanger) of accident causation. The results of the interviews are described for each problem area individually and are linked to state of the art scientific theory and models. Directions for ‘best practice’ examples are given and an indication for follow-up action is made.     

A Bayesian network analysis of workplace accidents caused by falls from a height

This article analyses, using Bayesian networks, the circumstances surrounding workplace tasks performed using auxiliary equipment (ladders, scaffolding, etc.) that may result in falls. The information source was a survey of employees working at a height. We were able to determine the usefulness of this approach – innovative in the accident research field – in identifying the causes that have the greatest bearing on accidents involving auxiliary equipment: in these cases, the adoption of incorrect postures during work and a worker’s inadequate knowledge of safety regulations. Likewise, the duration of tasks was also associated with both these variables, and therefore, with the accident rate. Bayesian networks also enable dependency relationships to be established between the different causes of accidents. This information – which is not usually furnished by conventional statistical methods applied in the field of labour risk prevention – allow a causality model to be defined for workplace accidents in a more realistic way. With this statistic tool, the expert is also provided with useful information that can be input to a management model for labour risk prevention.     

Severity analysis of Indian coal mine accidents – A retrospective study for 100 years

A retrospective study on severity analysis of Indian coal mines accidents for 100 years was done considering fatal and serious accidents and the resulting causalities. The impact of recommendations based on safety conferences and committees over the years was studied. An event evaluation algorithm (EEA) was developed for this purpose. The hazard rate functions and cumulative risk functions for major hazards in Indian coal mines were developed. The study evaluated the status of safety level as well as the scope of improvement for Indian coal mines safety.