Agrobiodiversity Under Different Property Regimes

Having an adequate and extensively recognized resource governance system is essential for the conservation and sustainable use of crop genetic resources in a highly populated planet. Despite the widely accepted importance of agrobiodiversity for future plant breeding and thus food security, there is still pervasive disagreement at the individual level on who should own genetic resources. The aim of the article is to provide conceptual clarification on the following concepts and their relation to agrobiodiversity stewardship: open access, commons, private property, state property and common heritage of humankind. After presenting each property regime, we will examine whether and how these incentivize the conservation, improvement and sharing of crop genetic resources, and conclude by defending a mixed property regime.     

Investigation of residence time and groundwater flux in Venice Lagoon: comparing radium isotope and hydrodynamical models

The four naturally-occurring isotopes of radium were coupled with a previously evaluated hydrodynamic model to determine the apparent age of surface waters and to quantify submarine groundwater discharge (SGD) into the Venice Lagoon, Italy.Mean apparent age of water in the Venice Lagoon was calculated using the ratio of ²²⁴Ra to ²²⁸Ra determined from 30 monitoring stations and a mean pore water endmember. Average apparent age was calculated to be 6.0 d using Ra ratios. This calculated age was very similar to average residence time calculated for the same period using a hydrodynamic model (5.8 d).A mass balance of Ra was accomplished by quantifying each of the sources and sinks of Ra in the lagoon, with the unknown variable being attributed to SGD. Total SGD were calculated to be 4.1 ± 1.5, 3.8 ± 0.7, 3.0 ± 1.3, and 3.5 ± 1.0 × 10¹⁰ L d⁻¹ for ^{223,224,226, 228}Ra, respectively, which are an order of magnitude larger than total mean fluvial discharge into the Venice Lagoon (3.1 × 10⁹ L d⁻¹). The SGD as a source of nutrients in the Venice Lagoon is also discussed and, though significant to the nutrient budget, is likely to be less important as the dominant control on SGD is recirculated seawater rather than freshwater.     

Mechanochemical degradation of chlorinated contaminants in fly ash with a calcium-based degradation reagent

This report presents our results in a low-temperature mechanochemical hydrodechlorination process applied to fly ash coming from a municipal waste incinerator in order to efficiently remove all traces of PCDDs, PCDFs and PCBs. We found that the most suitable degradation agent is a mixture of metallic calcium and calcium oxide. A sample of fly ash presenting a TEQ of 5200 pg g⁻¹ was completely detoxified (no traces of PCDDs, PCDFs and PCBs detected) after ball-milling at 400 rpm over night.     

Immobilization and volume reduction of heavy metals in municipal solid waste fly ash using nano-size calcium and iron-dispersed reagent

This study was conducted to examine the synthesis and application of novel nano-size calcium/iron-based composite material as an immobilizing and separation treatment of the heavy metals in fly ash from municipal solid waste incineration. After grinding with nano-Fe/Ca/CaO and with nano-Fe/Ca/CaO/[PO₄], approximately 30 wt% and 25 wt% of magnetic fraction fly ash were separated. The highest amount of entrapped heavy metals was found in the lowest weight of the magnetically separated fly ash fraction (i.e., 91% in 25% of treated fly ash). Heavy metals in the magnetic or nonmagnetic fly ash fractions were about 98% and 100% immobilized, respectively. Additionally, scanning electron microscopy combined with energy-dispersive X-ray spectrometry (SEM-EDS) observations indicate that the main fraction of enclosed/bound materials on treated fly ash includes Ca/PO₄-associated crystalline complexes. After nano-Fe/Ca/CaO/[PO₄] treatment, the heavy metal concentrations in the fly ash leachate were much lower than the Japan standard regulatory limit for hazardous waste landfills. These results appear to be extremely promising. The addition of a nano-Fe/Ca/CaO/PO₄ mixture with simple grinding technique is potentially applicable for the remediation and volume reduction of fly ash contaminated by heavy metals.

Implications: After grinding with nano-Fe/Ca/CaO and nano-Fe/Ca/CaO/[PO₄], approximately 30 wt% and 25 wt% of magnetic fraction fly ash were separated. The highest amount of entrapped heavy metals was found in the lowest weight of the magnetically separated fly ash fraction (i.e., 91% in 25% of treated fly ash), whereas heavy metals either in the magnetic or nonmagnetic fly ash fractions were about 98% and 100% immobilized. These results appear to be very promising, and the addition of nano-Fe/Ca/CaO/PO₄ mixture with simple grinding technique may be considered potentially applicable for the remediation and volume reduction of contaminated fly ash by heavy metals.     

Plant selection for a pilot phytoremediation study at a former skeet range

A pilot phytoremediation project was conducted at the Mukluk site in Sprague, Connecticut, formerly a private skeet shooting range. A series of experiments was conducted to investigate if any plants can be effective lead phytoextractors for this site that has very high soil lead concentrations and low soil pH. Greenhouse screening of plants for lead resistance and accumulation using field soil was implemented as the initial step before the field installation. Herbaceous plant species with known lead phytoextraction capabilities included Indian mustard and blue fescue; a few willow clones with purported heavy metal resistance were also tested. Based on the results of the greenhouse experiments, blue fescue appeared to be sensitive to high lead concentration in soil, and only willows and Indian mustard along with various soil amendments were selected for the field installation. Indian mustard grew poorly in most of the treatments at the site except in the compost and lime treatment. Lead accumulation by this species was low in all treatments. In contrast, willows showed tolerance to very high lead concentrations present in the soil and were able to uptake and translocate lead into aboveground tissues. However, lead content in aerial tissues was low, and no change in soil lead concentration at the site was recorded post‐harvest after one growing season. It appeared that highly unfavorable soil characteristics at the Mukluk site complicated the species selection, and no effective phytoextractors have been found for this location. These suggest that the feasibility of phytostabilization and possible production of biofuel from willow biomass on these types of sites should be further investigated. © 2010 Wiley Periodicals, Inc.     

Hot emission model for mobile sources: application to the metropolitan region of the city of Santiago, Chile

Depending on the final application, several methodologies for traffic emission estimation have been developed. Emission estimation based on total miles traveled or other average factors is a sufficient approach only for extended areas such as national or worldwide areas. For road emission control and strategies design, microscale analysis based on real-world emission estimations is often required. This involves actual driving behavior and emission factors of the local vehicle fleet under study. This paper reports on a microscale model for hot road emissions and its application to the metropolitan region of the city of Santiago, Chile. The methodology considers the street-by-street hot emission estimation with its temporal and spatial distribution. The input data come from experimental emission factors based on local driving patterns and traffic surveys of traffic flows for different vehicle categories. The methodology developed is able to estimate hourly hot road CO, total unburned hydrocarbons (THCs), particulate matter (PM), and NO(x) emissions for predefined day types and vehicle categories.     

Impact of error self-perception of aerobic capacity in the safety and efficacy of the lifeguards

Introduction. The strong physical demands that are required of lifeguards during rescues also require an accurate self-perception of one's fitness level to be able to regulate the intensity of effort. Objectives. The aim of this study was to determine the real aerobic capacity (RAC) and to compare it with two self-reported measurements: subjective appraisal of aerobic capacity (SAAC) and appraisal of physical exercise (APE). Methods. Fifty-two professional lifeguards were included in the study. For an objective assessment of RAC, the lifeguards’ maximum oxygen uptake (V_O2max) values were measured during treadmill stress tests. A fitness assessment questionnaire was used to obtain the SAAC and APE values. Results. We found a statistically significant association between the APE and RAC variables in the contingency analysis (p?V_O2max value below 43 ml kg^?1?min^?1 considered their aerobic capacity to be high or very high. Conclusion. This self-perception error of true aerobic capacity could lead to premature fatigue during a rescue, endangering both the lifeguard's life and the life of the victim. These data may help lifeguards and beach managers to become aware of the need to know lifeguards’ true physical conditions through testing and structured training programs.     

Spatial variation of organochlorine pesticides and dissolved organic matter in urban closed lakes

Abstract

Closed lakes located in urban parks act as sinks of organochlorine pesticides (OCPs), which have been used, for decades, as insecticides, herbicides and fungicides. The closed lakes from Bucharest, Romania, are periodically managed to prevent eutrophication and accumulation of pollutants. However, it is not known if these practices reduce or enhance the legacy pollution with OCPs. The aim of this study was to explore the spatial variation of OCPs in closed lakes. The total concentration of OCPs in water and sediments ranged between 0.0176 and 37.1?µg/L, and between 122 to 1,890?ng/g, respectively. The concentrations of OCPs were compared with the consensus-based sediment quality guidelines (SQGs) in order to evaluate the ecological risks of sediments. The highest potential adverse effects were associated with γ-HCH exposure. Periodical draining and dredging of lakes lead to the resuspension of contaminants, increasing pesticide bioavailability and accumulation in sediments. In addition, we observed that fluorescent dissolved organic matter (DOM) might influence the OCPs cycle. The quantity and character of fluorescent DOM can provide further insight into OCPs degradation. Also, this study may help urban planners to determine the state of urban waters and to find the best solution for water management.