Monitoring H2S air pollution caused by the industrial exploitation of geothermal energy: The pitfall of using lichens as bioindicators

This study showed that NH₃ emitted from geothermal power plants affects the surrounding epiphytic lichen vegetation and diversity, confounding the interpretation of lichen diversity counts in terms of air pollution by H₂S. The presence of nitrophytic lichen species around geothermal installations, determined by NH₃, caused relatively high diversity values that were not related with the levels of air pollution by H₂S. It is recommended that in the presence of NH₃ emission, nitrophytic species are excluded from the calculation of lichen diversity values.     

Valuing Improvements in The Water Rights System in South Africa: A Contingent Ranking Approach1

Speelman, Stijn, Stefano Farolfi, Aymen Frija, and Guido Van Huylenbroeck, 2010. Valuing Improvements in the Water Rights System in South Africa: A Contingent Ranking Approach. Journal of the American Water Resources Association (JAWRA) 46(6):1133–1144. DOI: 10.1111/j.1752-1688.2010.00480.x Abstract: In the context of increasing water scarcity, understanding is growing that irrigation water rights are important and that a lack of an effective water rights system constitutes a major reason for inefficient water management. This study carried out a contingent ranking experiment to study how smallholder irrigators in South Africa would value potential changes in water rights. Three specific dimensions of water rights, relevant for the South African case, are considered: duration, quality of title, and transferability. Results indicate that smallholder irrigators are prepared to pay considerably higher water prices if improvements are made in the water rights system. This implies that the proposed interventions in the water rights system would improve the efficiency and productivity of the small-scale irrigation sector. The increased willingness to pay could furthermore also assist the South African government to reach the objective of increased cost recovery.     

Toxic effects of four sulphonylureas herbicides on soil microbial biomass

The effect of four triazinyl-sulfonylurea herbicides (cinosulfuron, prosulfuron, thifensulfuron methyl, triasulfuron) on soil microbial biomass, soil respiration, metabolic activity, metabolic quotient, and some enzymatic activities (acid and alkaline phosphatase, β-glucosidase, arylsulphatase, and fluorescein diacetate hydrolysis) were monitored under controlled conditions over 30 days. The herbicides were applied at the normal field dose (FD) and at ten-fold (10 FD) the field dose, in order to mimic a long term toxic effect. The measured soil microbial parameters showed that the FD had slight effects on soil microflora, while at 10 FD the tested herbicides exerted a stronger detrimental effect on soil microbial biomass and its biochemical activities.     

Environmental release and mass flux partitioning of PCDD/Fs during normal and transient operation of full scale waste to energy plants

The paper reports on global release and mass partitioning in the flux of residues of PCDD/Fs, evaluated with dedicated field campaigns at a municipal solid waste incineration plant during normal and transient operation. Results are compared with those obtained in other installations equipped with furnaces, energy recovery options and flue gas treatment technologies representative of most of the European incineration plants currently in operation. Levels of the pollutants of interest were determined in all the solid, liquid and gaseous residues produced by every single facility, and the results analysed in terms of the effects arising from the fed waste and the configuration of the plant. PCDD/Fs total release between 1.5 and 45 microg I-TEQ per ton of burned waste was evaluated, with lower values resulting from the adoption of catalytic conversion process for flue gas treatment. Most of the mass flux emitted is associated with solid residues deriving from activated carbon PCCD/F dry removal options, with significant contributions also from fly ash produced by particulate removal devices located immediately downstream the boiler and from scrubber blowdowns treatment sludge. During transient operating conditions the dioxin total release may increase by 50% with comparison to steady-state functioning.     

Decontamination of soil containing POPs by the combined action of solid Fenton-like reagents and microwaves

The effect on halogenated aromatics of solid, non-toxic oxidants such as sodium percarbonate and the urea/hydrogen peroxide complex (Fenton-like reagents) was investigated. A microwaves-assisted, solvent-free method for soil decontamination is presented. It marks a considerable advance in the search of more efficient, environment-friendly procedures for the degradative oxidation of persistent organic pollutants. Residual pollutants in treated soil samples were determined by GC/MS analysis after solvent extraction or direct thermal desorption. Results showed that 4-chloronaphthol, 2,4-dichlorophenoxyacetic acid and p-nonylphenol had been degraded completely, 2,4-dibromophenol to a large extent.     

Evaluation of the impact on entomocoenosis of active agents allowed in organic olive farming against Bactrocera oleae (Gmelin, 1790)

Several attempts for evaluating environmental impact of active agents allowed in organic olive farming against Bactrocera oleae have been made, but very few studies were performed contemporaneously on more than one of them. Insects were chosen as indicators because they are known to react very quickly to environmental perturbations, mainly at the community level. In fact, the coenosis is the functional unit interacting with biotic and abiotic environmental parameters. Seven taxa, known for their sensitivity to habitat alterations, were sampled and grouped in functional groups: predators and parasitoids, phytophagouses and pollinators. The coenotic balance between these two functional groups was analyzed. The study was carried out in an organic olive orchard in the municipality of Terranova da Sibari, Cosenza, Southern Italy. The tested active agents (Azadirachtin, Rotenone, Copper Oxychloride) were sprayed twice (end of September and middle October). During the treatments the population dynamics of all the taxa were knocked-down. No one tested compound seems to be harmless to the entomocoenosis, particularly on phytophagouses and pollinators. In truly organic farming it is necessary to provide natural refuge areas to beneficial insects (i.e. pest antagonists) in which no active agents are sprayed and alternative preys could be found.     

Distribution of Cd and As in organs and tissues of four marine mammal species stranded along the Italian coasts

Concentrations of Cd and As were determined in organs and tissues (muscle, heart, kidney, lung and liver) of four cetacean species (Stenella coeruleoalba, Truncatus truncatus, Grampus griseus and Ziphius cavirostris) stranded along the Italian coasts during the period 2000-2009. Significant differences were found between Cd concentrations in the different analysed tissues. Particularly, the kidney shows the highest concentrations of Cd in all analysed specimens, followed by the liver. No systematic or statistically significant difference in As concentrations was found in the analysed tissues. Considerable differences of Cd and As values in samples from different geographical areas (Sicily Channel, Adriatic Sea and Tyrrhenian Sea) were found, with the highest values measured in samples from the Sicily Channel. This basically suggests that anthropogenic and natural sources significantly affect Cd and As content in cetaceans.     

Integrating functional connectivity and fire management for better conservation outcomes

Globally, the mean abundance of terrestrial animals has fallen by 50% since 1970, and populations face ongoing threats associated with habitat loss, fragmentation, climate change, and disturbance. Climate change can influence the quality of remaining habitat directly and indirectly by precipitating increases in the extent, frequency, and severity of natural disturbances, such as fire. Species face the combined threats of habitat clearance, changing climates, and altered disturbance regimes, each of which may interact and have cascading impacts on animal populations. Typically, conservation agencies are limited in their capacity to mitigate rates of habitat clearance, habitat fragmentation, or climate change, yet fire management is increasingly used worldwide to reduce wildfire risk and achieve conservation outcomes. A popular approach to ecological fire management involves the creation of fire mosaics to promote animal diversity. However, this strategy has 2 fundamental limitations: the effect of fire on animal movement within or among habitat patches is not considered and the implications of the current fire regime for long-term population persistence are overlooked. Spatial and temporal patterns in fire history can influence animal movement, which is essential to the survival of individual animals, maintenance of genetic diversity, and persistence of populations, species, and ecosystems. We argue that there is rich potential for fire managers to manipulate animal movement patterns; enhance functional connectivity, gene flow, and genetic diversity; and increase the capacity of populations to persist under shifting environmental conditions. Recent methodological advances, such as spatiotemporal connectivity modeling, spatially explicit individual-based simulation, and fire-regime modeling can be integrated to achieve better outcomes for biodiversity in human-modified, fire-prone landscapes. Article impact statement: Land managers may conserve populations by using fire to sustain or enhance functional connectivity.     

Quantifying the burden of managing wildlife diseases in multiple host species

Mitigation of infectious wildlife diseases is especially challenging where pathogens affect communities of multiple host species. Although most ecological studies recognize the challenge posed by multiple-species pathogens, the implications for management are typically assessed only qualitatively. Translating the intuitive understanding that multiple host species are important into practice requires a quantitative assessment of whether and how secondary host species should also be targeted by management and the effort this will require. Using a multiple-species compartmental model, we determined analytically whether and how intensively secondary host species should be managed to prevent outbreaks in focal hosts based on the reproduction number of individual host species and between-species transmission rates. We applied the model to the invasive pathogenic fungus Batrachochytrium salamandrivorans in a 2-host system in northern Europe. Avoiding a disease outbreak in the focal host (fire salamanders [Salamandra salamandra]) was impossible unless management also heavily targeted the secondary host (alpine newts [Ichthyosaura alpestris]). Preventing an outbreak in the community required targeted removal of at least 80% of each species. This proportion increased to 90% in the presence of an environmental reservoir of B. salamandrivorans and when the proportion of individuals removed could not be adjusted for different host species (e.g., when using traps that are not species specific). We recommend the focus of disease-mitigation plans should shift from focal species to the community level and calculate explicitly the management efforts required on secondary host species to move beyond the simple intuitive understanding that multiple host species may all influence the system. Failure to do so may lead to underestimating the magnitude of the effort required and ultimately to suboptimal or futile management attempts.