Future energy: in search of a scenario reflecting current and future pressures and trends

Environmental Economics and Policy Studies - Growing societal pressures, technological trends and government and industry actions are moving the world toward decarbonization and away from the...     

Changes in functional structure of soil bacterial communities due to fungicide and insecticide applications in canola

The fungicide vinclozolin and insecticide λ-cyhalothrin are widely used to control canola (Brassica spp.) diseases and insect pests, respectively, in Canada. We investigated non-target effects of these pesticides, applied at recommended rates, on soil microbial biomass, functional bacterial diversity and functional community structure of soil bacteria (by evaluating patterns of C substrate utilization) in canola rhizosphere and bulk soil at three locations in Alberta from 2002 to 2004. Experimental treatments were (a) untreated control, (b) vinclozolin fungicide foliar application, (c) λ-cyhalothrin insecticide foliar application, and (d) vinclozolin and λ-cyhalothrin applications. No significant pesticide effects on soil microbial biomass or functional bacterial diversity were observed, but the functional structures of soil bacteria were altered. In 1 of 12 cases, the control treatment had a different soil bacterial community structure from the 3 pesticide treatments. The fungicide treatment had different bacterial community structures from the control or insecticide treatments in 3 of 12 cases, the insecticide treatment had different community structures from the control or fungicide treatments in 4 of 12 cases, and the combined fungicide and insecticide treatment had different community structures from the other treatments in 3 of 12 cases. Therefore, evaluating soil bacterial functional structures revealed pesticide effects that were not detected when bacterial diversity or microbial biomass were measured in canola rhizosphere or bulk soil.     

Adaptive capacity determinants in developed states: examples from the Nordic countries and Russia

Adaptive capacity in a community context has so far mainly been studied in developing countries as well as indigenous communities in the industrialised world. This article adds to that literature through reviewing studies undertaken in the Nordic countries and Russia, highlighting the ways in which general determinants of adaptive capacity play out in Northern, industrialised contexts. The paper illustrates that the determinants of adaptive capacity in industrialised states exhibit systematic differences from mixed subsistence-cash based communities such as those found in Arctic Canada. We discuss in particular the importance of economic resources in a market-based system, technological competition, and infrastructure, in determining adaptive capacity of natural resource-dependent communities in the Nordic countries and Russia. The paper also illustrates differences in adaptive capacity within the case study region, including between peripheral and central locations with regard to economic resources and diversification possibilities, and between Nordic and Russian cases with regard to infrastructure and technology access. The findings indicate that understanding of determinants of adaptive capacity in resource-dependent communities would benefit from both further contextualisation and broad comparison, across different types of political and administrative systems.     

Barriers to evidence use for sustainability: Insights from pesticide policy and practice

Calls for supporting sustainability through more and better research rest on an incomplete understanding of scientific evidence use. We argue that a variety of barriers to a transformative impact of evidence arises from diverse actor motivations within different stages of evidence use. We abductively specify this variety in policy and practice arenas for three actor motivations (truth-seeking, sense-making, and utility-maximizing) and five stages (evidence production, uptake, influence on decisions, effects on sustainability outcomes, and feedback from outcome evaluations). Our interdisciplinary synthesis focuses on the sustainability challenge of reducing environmental and human health risks of agricultural pesticides. It identifies barriers resulting from (1) truth-seekers’ desire to reduce uncertainty that is complicated by evidence gaps, (2) sense-makers’ evidence needs that differ from the type of evidence available, and (3) utility-maximizers’ interests that guide strategic evidence use. We outline context-specific research–policy–practice measures to increase evidence use for sustainable transformation in pesticides and beyond.     

Environmental education research news

This report was by John F. Disinger, Professor of Natural Resources, and Jennifer L. Tomsen, Graduate Teaching Associate in Natural Resources, The Ohio State University, Columbus, Ohio, 43210–1085, USA.     

Jellyfish aggregations and leatherback turtle foraging patterns in a temperate coastal environment

Leatherback turtles (Dermochelys coriacea) are obligate predators of gelatinous zooplankton. However, the spatial relationship between predator and prey remains poorly understood beyond sporadic and localized reports. To examine how jellyfish (Phylum Cnidaria: Orders Semaeostomeae and Rhizostomeae) might drive the broad-scale distribution of this wide ranging species, we employed aerial surveys to map jellyfish throughout a temperate coastal shelf area bordering the northeast Atlantic. Previously unknown, consistent aggregations of Rhizostoma octopus extending over tens of square kilometers were identified in distinct coastal "hotspots" during consecutive years (2003-2005). Examination of retrospective sightings data (>50 yr) suggested that 22.5% of leatherback distribution could be explained by these hotspots, with the inference that these coastal features may be sufficiently consistent in space and time to drive long-term foraging associations.     

Distribution and evolution of genetic caste determination in Pogonomyrmex seed-harvester ants

We examined the distribution and ancestral relationships of genetic caste determination (GCD) in 46 populations of the seed-harvester ants Pogonomyrmex barbatus and P. rugosus across the east-to-west range of their distributions. Using a mtDNA sequence and two nuclear markers diagnostic for GCD, we distinguished three classes of population phenotypes: those with GCD, no evidence of GCD, and mixed (both GCD and non-GCD colonies present). The GCD phenotype was geographically widespread across the range of both morphospecies, occurring in 20 of 46 sampled populations. Molecular data suggest three reproductively isolated and cryptic lineages within each morphospecies, and no present hybridization. Mapping the GCD phenotype onto a mtDNA phylogeny indicates that GCD in P. rugosus was acquired from P. barbatus, suggesting that interspecific hybridization may not be the causal agent of GCD, but may simply provide an avenue for GCD to spread from one species (or subspecies) to another. We hypothesize that the origin of GCD involved a genetic mutation with a major effect on caste determination. This mutation generates genetic conflict and results in the partitioning and maintenance of distinct allele (or gene set) combinations that confer differences in developmental caste fate. The outcome is two dependent lineages within each population; inter-lineage matings produce workers, while intra-lineage matings produce reproductives. Both lineages are needed to produce a caste-functional colony, resulting in two reproductively isolated yet interdependent lineages. Pogonomyrmex populations composed of dependent lineages provide a unique opportunity to investigate genetic variation underlying phenotypic plasticity and its impact on the evolution of social structure.     

Evaluating the effectiveness of a logger safety training program

INTRODUCTION: Logger safety training programs are rarely, if ever, evaluated as to their effectiveness in reducing injuries. METHOD: Workers' compensation claim rates were used to evaluate the effectiveness of a logger safety training program, the West Virginia Loggers' Safety Initiative (LSI). RESULTS: There was no claim rate decline detected in the majority (67%) of companies that participated in all 4 years of the LSI. Furthermore, their rate did not differ from the rest of the WV logging industry that did not participate in the LSI. Worker turnover was significantly related to claim rates; companies with higher turnover of employees had higher claim rates. Companies using feller bunchers to harvest trees at least part of the time had a significantly lower claim rate than companies not using them. Companies that had more inspections per year had lower claim rates. CONCLUSIONS: High injury rates persist even in companies that receive safety training; high employee turnover may affect the efficacy of training programs. The logging industry should be encouraged to facilitate the mechanization of logging tasks, to address barriers to employee retention, and to increase the number of in-the-field performance monitoring inspections. Impact on industry There are many states whose logger safety programs include only about 4-8 hours of safe work practices training. These states may look to West Virginia's expanded training program (the LSI) as a model for their own programs. However, the LSI training may not be reaching loggers due to the delay in administering training to new employees and high levels of employee turnover. Regardless of training status, loggers' claim rates decline significantly the longer they work for a company. It may be that high injury rates in the state of West Virginia would be best addressed by finding ways to encourage and facilitate companies to become more mechanized in their harvesting practices, and to increase employee tenure. Increasing the number of yearly performance inspections may also be a venue to reduce claim rates. Future research could investigate in better detail the working conditions of West Virginia loggers and identify barriers to job tenure, particularly for workers whose primary job task is chainsaw operation. A larger-scale study of the effect of performance monitoring inspections on claim rates is also warranted.     

Longitudinal examination of underage drinking and subsequent drinking and risky driving

INTRODUCTION: Alcohol use, alcohol misuse, and risky driving from adolescence into young adulthood were compared by drinking onset age. METHODS: Surveys were administered in Grades 5/6, 6/7, 7/8, 10, 12, and at approximately age 23. Participants were placed into Drinking Onset groups based on self-reported alcohol use frequency on the adolescent surveys. Driving records were examined in three age periods: under 21, 21-25, and 26+. RESULTS: The earliest drinking initiators reported higher alcohol use and misuse on each survey, and were more likely to have risky driving offenses before age 21 and to have alcohol driving offenses in all three age periods. DISCUSSION: The earliest drinking initiators engaged in risky drinking behavior and risky driving behavior that was consistently higher than those with later drinking initiation, beginning in adolescence and persisting well into young adulthood.     

Trajectories of zooplankton recovery in the Little Rock Lake whole-lake acidification experiment.

Understanding the factors that affect biological recovery from environmental stressors such as acidification is an important challenge in ecology. Here we report on zooplankton community recovery following the experimental acidification of Little Rock Lake, Wisconsin, USA. One decade following cessation of acid additions to the northern basin of Little Rock Lake (LRL), recovery of the zooplankton community was complete. Approximately 40% of zooplankton species in the lake exhibited a recovery lag in which biological recovery to reference basin levels was delayed by 1-6 yr after pH recovered to the level at which the species originally responded. Delays in recovery such as those we observed in LRL may be attributable to "biological resistance" wherein establishment of viable populations of key acid-sensitive species following water quality improvements is prevented by other components of the community that thrived during acidification. Indeed, we observed that the recovery of species that thrived during acidification tended to precede recovery of species that declined during acidification. In addition, correspondence analysis indicated that the zooplankton community followed different pathways during acidification and recovery, suggesting that there is substantial hysteresis in zooplankton recovery from acidification. By providing an example of a relatively rapid recovery from short-term acidification, zooplankton community recovery from experimental acidification in LRL generally reinforces the positive outlook for recovery reported for other acidified lakes.