A Generic Bio-Economic Farm Model for Environmental and Economic Assessment of Agricultural Systems

Bio-economic farm models are tools to evaluate ex-post or to assess ex-ante the impact of policy and technology change on agriculture, economics and environment. Recently, various BEFMs have been developed, often for one purpose or location, but hardly any of these models are re-used later for other purposes or locations. The Farm System Simulator (FSSIM) provides a generic framework enabling the application of BEFMs under various situations and for different purposes (generating supply response functions and detailed regional or farm type assessments). FSSIM is set up as a component-based framework with components representing farmer objectives, risk, calibration, policies, current activities, alternative activities and different types of activities (e.g., annual and perennial cropping and livestock). The generic nature of FSSIM is evaluated using five criteria by examining its applications. FSSIM has been applied for different climate zones and soil types (criterion 1) and to a range of different farm types (criterion 2) with different specializations, intensities and sizes. In most applications FSSIM has been used to assess the effects of policy changes and in two applications to assess the impact of technological innovations (criterion 3). In the various applications, different data sources, level of detail (e.g., criterion 4) and model configurations have been used. FSSIM has been linked to an economic and several biophysical models (criterion 5). The model is available for applications to other conditions and research issues, and it is open to be further tested and to be extended with new components, indicators or linkages to other models.     

Distribution of polycyclic aromatic hydrocarbons in urban stormwater in Queensland, Australia

This paper reports the distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in wash-off in urban stormwater in Gold Coast, Australia. Runoff samples collected from residential, industrial and commercial sites were separated into a dissolved fraction (<0.45 μm), and three particulate fractions (0.45-75 μm, 75-150 μm and >150 μm). Patterns in the distribution of PAHs in the fractions were investigated using Principal Component Analysis. Regardless of the land use and particle size fraction characteristics, the presence of organic carbon plays a dominant role in the distribution of PAHs. The PAHs concentrations were also found to decrease with rainfall duration. Generally, the 1- and 2-year average recurrence interval rainfall events were associated with the majority of the PAHs and the wash-off was a source limiting process. In the context of stormwater quality mitigation, targeting the initial part of the rainfall event is the most effective treatment strategy. The implications of the study results for urban stormwater quality management are also discussed.     

Kinetics of the tropospheric formaldehyde loss onto mineral dust and urban surfaces

The kinetics of the heterogeneous reaction between gaseous HCHO and TiO₂/SiO₂ mineral coatings were investigated using a coated-wall flow tube to mimic HCHO loss on mineral aerosol and TiO₂ coated depolluting urban surfaces. The measured uptake kinetics were strongly enhanced when the flow tube was irradiated with 340–420 nm UV light with an irradiance of 1.45 mW cm^?2. The associated BET uptake coefficients ranged from (3.00 ± 0.45) × 10^?9 to (2.26 ± 0.34) × 10^?6 and were strongly dependent on HCHO initial concentration, relative humidity, temperature, and TiO₂ content in the mineral coating, which ranged from 3.5 to 32.5 ppbv, 6–70%, 278–303 K, and 1–100 %wt, respectively. The measured kinetics were well described using a Langmuir–Hinshelwood type formalism. The estimated uptake coefficients were used to discuss the importance of heterogeneous HCHO surface loss, in terms of deposition lifetimes, as compared to major homogeneous gas-phase losses such as OH reaction and photolysis. It is found that deposition may compete with gas-phase removal of HCHO in a dense urban environment if more than 10% of the urban surface is covered with TiO₂ treated material.     

An urban emissions inventory for South America and its application in numerical modeling of atmospheric chemical composition at local and regional scales

This work describes the development of an urban vehicle emissions inventory for South America, based on the analysis and aggregation of available inventories for major cities, with emphasis on its application in regional atmospheric chemistry modeling. Due to the limited number of available local inventories, urban emissions were extrapolated based on the correlation between city vehicle density and mobile source emissions of carbon monoxide (CO) and nitrogen oxides (NOx). Emissions were geographically distributed using a methodology that delimits urban areas using high spatial resolution remote sensing products. This numerical algorithm enabled a more precise representation of urban centers. The derived regional inventory was evaluated by analyzing the performance of a chemical weather forecast model in relation to observations of CO, NOx and O₃ in two different urban areas, São Paulo and Belo Horizonte. The gas mixing ratios simulated using the proposed regional inventory show good agreement with observations, consistently representing their hourly and daily variability. These results show that the integration of municipal inventories in a regional emissions map and their precise distribution in fine scale resolutions are important tools in regional atmospheric chemistry modeling.     

Cesium-137 contamination of oak (Quercus petrae Liebl.) from sub-mediterranean zone in South Bulgaria

This study focuses on the cesium-137 (¹³⁷Cs) contamination in grass and in different compartments of oak trees growing in ecosystems, located in the zone with sub-mediterranean climate in South Bulgaria, characterized with high summer temperatures, low precipitation and often periods of drought. In 2008, three experimental sites - PP1, PP2, PP3 - were sampled in oak ecosystems from Maleshevska Mountain at 900 m above sea level. Samples from grass species and oak tree leaves, branches with different diameter, wood disks and bark were analyzed for ¹³⁷Cs activity with γ-spectrometry. The soil-to-plant transfer factor (TF) values for ¹³⁷Cs were estimated differentiating different tree compartments. Our findings showed relatively high activity concentrations of ¹³⁷Cs in oak trees even 22 years after the Chernobyl accident. The grass under oak was less contaminated compared with the oak trees. The different organs of oak trees could be distinguished according to the ¹³⁷Cs contamination as follows: bark > branches (d < 1 cm) > leaves > branches (d > 3 cm) > wood. The relatively higher contamination of bark compared with the new-formed biomass suggested that a significant part of ¹³⁷Cs was accumulated as a result of direct adsorption at the time of the main contamination event. The TF values obtained and the presence of ¹³⁷Cs in the branches, leaves and in the wood formed after 1986 confirmed that 22 years after the contamination, the main mechanism of ¹³⁷Cs entrance in tree biomass was the root uptake.     

How Resilient Are Europe’s Inshore Fishing Communities to Change? Differences Between the North and the South

One would hypothesize that the Common Fisheries Policy, as the umbrella framework for fisheries management in the EU would have the greatest impact on fishers’ communities across Europe. There are, however, biological, economic, social, and political factors, which vary among fishing communities that can affect how these communities react to changes. This paper explores the links between institutional arrangements and ecological dynamics in two European inshore fisheries socio-ecological systems, using a resilience framework. The Mediterranean small-scale fishers do not seem to have been particularly affected by the Common Fisheries Policy regulations but appear affected by competition with the politically strong recreational fishers and the invasion of the rabbit fish population. The inshore fishers along the East coast of Scotland believe that their interests are not as sufficiently protected as the interests of their offshore counterpart. Decisions and initiatives at global, EU, and sometimes national level, tend to take into account those fisheries sectors which have a national economic importance. A socio-ecological analysis can shift the focus from biological and economic aspects to more sustainable long-term delivery of environmental benefits linked to human wellbeing.     

Matrix effect on the performance of headspace solid phase microextraction method for the analysis of target volatile organic compounds (VOCs) in environmental samples

Solid phase microextraction (SPME) is a fast, cheap and solvent free methodology widely used for environmental analysis. A SPME methodology has been optimized for the analysis of VOCs in a range of matrices covering different soils of varying textures, organic matrices from manures and composts from different origins, and biochars. The performance of the technique was compared for the different matrices spiked with a multicomponent VOC mixture, selected to cover different VOC groups of environmental relevance (ketone, terpene, alcohol, aliphatic hydrocarbons and alkylbenzenes). VOC recovery was dependent on the nature itself of the VOC and the matrix characteristics. The SPME analysis of non-polar compounds, such as alkylbenzenes, terpenes and aliphatic hydrocarbons, was markedly affected by the type of matrix as a consequence of the competition for the adsorption sites in the SPME fiber. These non-polar compounds were strongly retained in the biochar surfaces limiting the use of SPME for this type of matrices. However, this adsorption capacity was not evident when biochar had undergone a weathering/aging process through composting. Polar compounds (alcohol and ketone) showed a similar behavior in all matrices, as a consequence of the hydrophilic characteristics, affected by water content in the matrix. SPME showed a good performance for soils and organic matrices especially for non-polar compounds, achieving a limit of detection (LD) and limit of quantification (LQ) of 0.02 and 0.03 ng g⁻¹ for non-polar compounds and poor extraction for more hydrophilic and polar compounds (LD and LQ higher 310 and 490 ng g⁻¹). The characteristics of the matrix, especially pH and organic matter, had a marked impact on SPME, due to the competition of the analytes for active sites in the fiber, but VOC biodegradation should not be discarded in matrices with active microbial biomass.     

Organochlorine compounds in bovine milk from the state of Mato Grosso do Sul – Brazil

Organochlorines are highly hydrophobic, synthetic organic pollutants that accumulate in the environment and in food webs. The primary route of human exposure to organochlorines is through food-mainly fat-rich food of animal origin such as meat, fish, and dairy products. Here we determined the presence and concentration of organochlorine residues in pasteurized milk from Mato Grosso do Sul, Brazil, to monitor consumer exposure to these contaminants. Organochlorine pesticides in milk samples were analyzed using solid phase extraction in octadecyl silica-prepacked columns and identified by gas chromatography using an electron capture detector. Of the 100 composite samples analyzed, more than 90% contained residues of organochlorine pesticides: aldrin was present in 44% of the samples, followed by ∑DDT (36%), mirex (34%), endosulfan (32%), chlordane (17%), dicofol (14%), heptachlor (11%) and dieldrin (11%). Compared to the values established by law, the concentration of the compounds in some samples was above the reference values. Given the importance that milk and its products have in the human diet, it is essential to know whether the levels of pesticide residues are kept well below the recommended levels to minimize the risk to human health.     

The bioaccumulation of Molybdenum in the earthworm Eisenia andrei: influence of soil properties and ageing

Mo bioaccumulation in the earthworm Eisenia andrei was determined after 28 d exposure in ten different European field soils (pH 4.4-7.8) and an artificial soil, freshly spiked with Na₂MoO₄ at concentrations between 3.2 and 3200 mg Mo kg⁻¹ dry soil. Three field soils were also tested after ageing for 11 months. Earthworm Mo concentrations generally levelled off at high exposure levels but in most soils showed a (nearly) linear increase with increasing soil concentrations in the lower, non-toxic range (below EC10 or NOEC for reproduction effects). Bioaccumulation (BAF) and Bioconcentration factors (BCF) were calculated as the ratio of earthworm concentration to soil and estimated porewater concentrations, respectively. BAFs (0.35-3.44) and BCFs (1.31-276) did not seem much affected by soil concentration, suggesting that earthworms are not capable of regulating their internal Mo concentrations. BAF was best predicted by ammonium oxalate-extractable iron (Fe_ox) and phosphor (P_ox) contents of the soils.     

Reductive debromination of nonabrominated diphenyl ethers by sodium borohydride and identification of octabrominated diphenyl ether products

A method was developed to study reductive transformation of highly brominated diphenyl ethers (BDEs). The method development is a part of a broader project where it will be used to determine the susceptibility of environmental pollutants to reductive conditions, in an attempt to create a scheme for determination of chemical’s persistence. This paper focuses on identification of octabrominated diphenyl ether transformation products from reductive debromination of the three nonabrominated diphenyl congeners (nonaBDE), BDE-206, -207 and -208. Sodium borohydride was used to explore the reductive debromination of the nonaBDEs. The transformation products were collected at two time-points and identified products were quantified by GC-MS. The reduction of the nonaBDEs lead primarily to debrominated products, mainly octaBDEs. The three nonabrominated DEs gave isomer-related transformation product patterns. BDE-207 and BDE-208 showed a propensity for ortho-debromination in the initial reaction step, while no discrimination between initial debromination positions was seen for BDE-206. All three nonabrominated DEs displayed a preferred initial debromination on the fully brominated DE ring.