Tiny Stowaways: Analyzing the Economic Benefits of a U.S. Environmental Protection Agency Permit Regulating Ballast Water Discharges

The U.S. Environmental Protection Agency has proposed permitting ballast water discharges—a benefit of which would be to reduce the economic damages associated with the introduction and spread of aquatic invasive species. Research on ship-borne aquatic invasive species has been conducted in earnest for decades, but determining the economic damages they cause remains troublesome. Furthermore, with the exception of harmful algal blooms, the economic consequences of microscopic invaders have not been studied, despite their potentially great negative effects. In this paper, we show how to estimate the economic benefits of preventing the introduction and spread of harmful bacteria, microalgae, and viruses delivered in U.S. waters. Our calculations of net social welfare show the damages from a localized incident, cholera-causing bacteria found in shellfish in the Gulf of Mexico, to be approximately $706,000 (2006$). On a larger scale, harmful algal species have the potential to be transported in ships’ ballast tanks, and their effects in the United States have been to reduce commercial fisheries landings and impair water quality. We examine the economic repercussions of one bloom-forming species. Finally, we consider the possible translocation within the Great Lakes of a virus that has the potential to harm commercial and recreational fisheries. These calculations illustrate an approach to quantifying the benefits of preventing invasive aquatic microorganisms from controls on ballast water discharges. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency.     

The interactions of cetyltrimethylammonium with mitochondria: an uncoupler or a detergent?

The interactions of cetyltrimethylammonium (CTA) with mitochondria have been investigated. We confirm, as already observed in a previous paper, that this compound behaves as proton carrier (or uncoupler) of the oxidative phosphorylation, but evidences suggest that this compound enhances the membrane permeability to many other compounds such as sucrose. We conclude therefore that CTA as a detergent enhances membrane permeability to all ions including protons. Some evidences are also given that the inhibitory effect of CTA on the mitochondrial respiratory chain is a consequence of the swelling induced.     

Effect of biochar on the fate of volatile petroleum hydrocarbons in an aerobic sandy soil

Biochar addition to soil is currently being investigated as a novel technology to remediate polluted sites. A critical consideration is the impact of biochar on the intrinsic microbial pollutant degradation, in particular at sites polluted with a mixture of readily biodegradable and more persistent organic pollutants. We therefore studied the impact of biochar (2% on dry weight basis) on the fate of volatile petroleum hydrocarbons in an aerobic sandy soil with batch and column studies. The soil-water partitioning coefficient, K(d), was enhanced in the biochar-amended soil up to a factor 36, and petroleum hydrocarbon vapor migration was retarded accordingly. Despite increased sorption, in particular of monoaromatic hydrocarbons, the overall microbial respiration was comparable in the biochar-amended and unamended soil. This was due to more rapid biodegradation of linear, cyclic and branched alkanes in the biochar amended soil. We concluded that the total petroleum hydrocarbon degradation rate was controlled by a factor other than substrate availability and the reduced availability of monoaromatic hydrocarbons in the biochar amended soil led to greater biodegradation of the other petroleum compounds.     

Sampling for weed spatial distribution mapping need not be adaptive

Weeds are species of interest for ecologists because they are competitors of the crop for resources but they also play an important role in maintaining biodiversity in agroecosystems. To study their spatial distribution at the field scale, only sampled observations are available due to the cost of sampling. Weeds sampling strategies are static. However, in the domain of spatial sampling, adaptive strategies have also been developed with, for some of them, an important on-line or off-line computational cost. In this article we provide answers to the following question: Are the current adaptive sampling methods efficient enough to motivate a wider use in practice when sampling a weed species at a field scale? We provide a comparison of the behaviour of 8 static strategies and 3 adaptive ones on four criteria: density class estimation, map restoration, spatial aggregation estimation, and sampling duration. From two weeds data sets, we estimated six contrasted Markov Random Field (MRF) models of weed density class spatial distribution and a model for sampling duration. The MRF models were then used to compare the strategies on a large set of simulated maps. Our main finding was that there is no clear gain in using adaptive sampling strategies rather than static ones for the three first criteria, and adaptive strategies were associated to longer sampling duration. This conclusion points out that for weed mapping, it is more important to build a good model of spatial distribution, than to propose complex adaptive sampling strategies.     

Reuse of municipal solid wastes incineration fly ashes in concrete mixtures

This study is aimed at assessing the feasibility of concrete production using stabilized m.s.w. (municipal solid waste) incineration fly ashes in addition to natural aggregates. The tested fly ashes were washed and milled, then stabilized by a cement-lime process and finally were reused as a "recycled aggregate" for cement mixture production, in substitution of a natural aggregate (with dosage of 200-400 kg m(-3)). These mixtures, after curing, were characterized with conventional physical-mechanical tests (compression, traction, flexure, modulus of elasticity, shrinkage). In samples containing 200 kg(waste) m(-3)(concrete), a good compressive strength was achieved after 28 days of curing. Furthermore, concrete leaching behavior was evaluated by means of different leaching tests, both on milled and on monolithic samples. Experimental results showed a remarkable reduction of metal leaching in comparison with raw waste. In some cases, similar behavior was observed in "natural" concrete (produced with natural aggregates) and in "waste containing" concrete.     

Opportunities and Challenges in Applying the 3Rs to Zoos and Aquariums

Since Russell and Burch (1959) suggested the principles of replacement, reduction, and refinement (3Rs) as a foundation for animal research, their influence has only grown in the research community. In this paper, we discuss whether the 3Rs can be constructively used as a prism to analyse decisions regarding the welfare of animals housed in zoos and aquariums (henceforth “zoo animals”). We analyse opportunities and challenges for each of the three Rs when applied to zoo animals. We discuss the following reasons to consider the use of the 3Rs in relation to zoo animals: (1) there are similarities between motivations for housing animals in zoos and using them in research that are ethically relevant to consider; (2) the professional zoo community has committed to progress towards evidence-based best practice models to ensure and enhance the welfare of animals housed in zoos; and (3) there is a growing public concern regarding the welfare of zoo animals which can, to some extent, be met by viewing current practices through the prism of the 3Rs.

     

Effects of olive mill wastewater and olive mill pomace on soil physicochemical properties and soil polyphenols

Journal of Material Cycles and Waste Management - Every year, worldwide olive oil extraction processes produce huge amounts of by-products such as (olive mill wastewater and olive mill pomace) in a...     

Valuations of Transport Nuisances and Cognitive Biases: A Survey Laboratory Experiment in the Pyrenees Region

Environmental Modeling & Assessment - We designed a survey that aims at estimating individual willingness-to-pay to reduce noise and air pollution arising from transportation activity near the...