The clustering conditions for managing creative tourism destinations: the Alqueva region case,Portugal

The paper discusses conditions and format of a cluster model to support the management of a potential creative tourism destination in a setting where regional cross-sectoral collaboration is lacking. Creative tourism development requires a flexible framework and a healthy collaboration environment, more so when associated with resources shared by several stakeholders. This article focuses on the tourism potential of archaeological knowledge discovered during the environmental impact assessment of the Alqueva dam (Alentejo, Portugal). Interviews were conducted with 38 regional actors in the tourism and heritage sectors, as well as the dam developers and the companies responsible for archaeological interventions. Findings indicate that the lack of specific local policy addressing archaeological heritage hampers its potential use for tourism development, which is further aggravated by the absence of stakeholder communication and cooperation. A conceptual cluster model for the management of creative tourism destinations based on heritage resources and other local resources is proposed.     

Assessing supercritical fluid extraction for the analysis of fipronil,kresoxim-methyl,acrinathrin, and pyridaben residues in melon

An analytical method, using supercritical fluid extraction (SFE), was assessed for residue analysis of the insecticides fipronil, acrinathrin and pyridaben and the fungicide kresoxim-methyl in melons. Extraction conditions were optimized on glass beads, as inert material, evaluating different pressures, temperatures, and CO₂ volumes. Also, the extractability of pesticides from hydromatrix and anhydrous magnesium sulfate was evaluated. Both adsorbents were evaluated for the preparation of SFE-spiked melon samples. Extractions of fortified samples were done using 20 mL of CO₂, 300 atm, and 50°C. Different extraction conditions, including the addition of water and methanol as a static modifier, were used to assess the extractability of these pesticides, and the addition of methanol was demonstrated to improve the extraction of all the studied pesticides.     

Application of Sensitivity and Flux Analyses for the Reduction of Model Predicting the Photooxidative Degradation of an Azo Dye in Aqueous Media

The prediction of the system behavior is of significant interest when evaluating appropriate technologies for wastewater treatment. The robust prediction could be achieved by empirical mathematical modeling techniques, but they do not include steps in degradation of organic pollutants. Mechanistic models (MM) include chemical/physical phenomena, but may also include numerous reactions resulting with the complicated kinetic expressions with large number of parameters. This modeling approach can be challenging for complex system such as advanced oxidation processes. With the goal to reduce the number of reactions involved in developed MM, keeping the high prediction power, sensitivity, and flux analyses was employed. The results showed that MM describing the degradation of organic dye in water matrix by photooxidation processes can be significantly simplified, by reducing the number of reactions included without affecting the predictive power. The calculated root mean square deviation values between data predicted by MM and reduced MM_R differ insignificantly (≤1.4 %).     

Health concerns of consuming cockles (Cerastoderma edule L.) from a low contaminated coastal system

Commercial and recreational harvesting of shellfish within the coastal systems is usually very extensive. Since these ecosystems are frequently subjected to contamination, namely from agricultural, urban and industrial activities, and shellfish generally display a high capacity to bioaccumulate metals, populations may be at risk in terms of toxic metal exposure as a consequence of the harvesting and ingestion of near shore coastal marine organisms. Shellfish is regularly tested for concentrations of metals and other contaminants by legal authorities for commercial purposes, but although health officials use total metal as standards of food safety, only a part of the metal accumulated in shellfish is available to be assimilated and to cause toxic effect. In order to elucidate these issues an investigation on cockles inhabiting the Aveiro estuary was conducted. Element levels in sediments and wild Cerastoderma edule from sampling areas with different levels of contamination were measured; total element burden of cockles was related to accessible fraction for assimilation (TAM); element concentrations in wild C. edule were compared to EFSA (European Food Safe Authorities), USFDA (United States Food and Drug Administration) and FSANZ (Food Standards Australia and New Zealand) maximum levels (MLs); and the amount of cockle flesh needed to be consumed to exceed provisional tolerable weekly intake (PTWI) was determined. The present work showed that although sediment metal and metalloid contamination in Aveiro estuary is low the concentration of elements in C. edule does not reflect the contamination of the sediment. Aluminium (Al) and mercury (Hg) were the less and nickel (Ni), lead (Pb), zinc (Zn) and cadmium (Cd) were the most bioaccumulated metals by cockles. Comparison of MLs from international organisations with the concentration of elements in C. edule showed that arsenic (As) and Pb exceeded standard levels. The ingestion of less than 1 kg for As and 1.5 kg for Pb of cockles would result in exceeding the PTWI threshold (0.015 and 0.025 mg kg?1 week?1 respectively) in any of the areas considered in the study. Cd and Al also appear to be limiting elements for human consumption. Indeed, consumption of more than 3.1 kg and 2.1 kg of whole cockle soft part from one of the study areas during a single week would lead to exceedance of the recommended PTWI value for Cd (0.007 mg kg?1 week?1) and Al (7 mg kg?1 week?1) respectively. The health concerns to humans from cockle consumption from Aveiro estuary are discussed.     

Degradation of phenols in olive oil mill wastewater by biological,enzymatic, and photo-Fenton oxidation

Background, aim, and scope  

Olive oil mill wastewater (OOMW) environmental impacts minimization have been attempted by developing more effective processes, but no chemical or biological treatments were found to be totally effective to mitigate their impact on receiving systems. This work is the first that reports simultaneously the efficiency of three different approaches: biological treatment by two fungal species (Trametes versicolor or Pleurotus sajor caju), enzymatic treatment by laccase, and chemical treatment by photo-Fenton oxidation on phenols removal.     

Inferring episodic atmospheric iron fluxes in the Western South Atlantic

Iron (Fe) and other trace elements such as Zn, Mn, Ni and Cu are known as key-factors in marine biogeochemical cycles. It is believed that ocean primary productivity blooms in iron deficient regions can be triggered by iron in aeolian dust. Up to now, scarce aerosol elemental composition, based on measurements over sea at the Western South Atlantic (WSA), exist. An association between the Patagonian semi-desert dust/Fe and chlorophyll-a variability at the Argentinean continental shelf is essentially inferred from models. We present here experimental data of Fe enriched aerosols over the WSA between latitudes 22°S–62°S, during 4 oceanographic campaigns between 2002 and 2005. These data allowed inferring the atmospheric Fe flux onto different latitudinal bands which varied from 30.4 to 1688 nmolFe m^?2 day^?1 (October 29th–November 15th, 2003); 5.83–1586 nmolFe m^?2 day^?1 (February 15th–March 6th, 2004) and 4.73–586 nmolFe m^?2 day^?1(October 21st–November 5th, 2005).     

Bioreactor treatment of municipal solid waste landfill leachates: characterization of organic fractions

Quantitative and qualitative changes in organic matter were studied at different stages of treatment in a bioreactor designed to process leachates from a municipal solid waste landfill. The particulate matter (PM) and macromolecular fractions of the dissolved organic matter with solubility properties comparable to humic (acid-insoluble) and fulvic (acid-soluble) acid fractions (AI, AS, respectively) from the incoming black liquid, the bioreactor content, and the final processed effluent were isolated, quantified, and characterized by visible and infrared (IR) spectroscopies. The macromolecular signature either aliphatic (glycopeptides, carbohydrates) or aromatic (coinciding with infrared patterns of lignin, tannins etc.) enabled us to characterize the different organic fractions during the course of microbial transformation. The results reveal significant changes in the nitrogen speciation patterns within the different organic fractions isolated from the wastewater. The final increase in the relative proportions of nitrogen in the least aromatic AS fraction during microbial transformation could be related to protein formation inside the bioreactor. After biological treatment and ultrafiltration, the amount of organic matter was reduced by approximately 70%, whereas aromaticity increased in all fractions, indicating preferential elimination of aliphatic wastewater compounds. Most of the remaining fractions at the end of the process consisted of a yellow residue rich in low molecular weight AS fractions.     

Nest-maintenance effort and health status in chinstrap penguins, Pygoscelis antarctica: the functional significance of stone-provisioning behaviour

Stone provisioning is a nest-maintenance activity accomplished by pygoscelid penguins after reliefs during the incubation/brooding period. The functional significance of this behaviour has been mainly explained as a parental strategy preventing nest flooding under detrimental weather conditions. In addition, and in the light of recent studies, this behaviour could also fit into the sexual selection process. In this study, we tested the first idea, that is, whether stone provisioning is a nest-maintenance behaviour to increase egg/nestling survival by lowering the risk of nest flooding, and can thus be considered a form of parental care. Additionally, we investigated if the effort invested by parents in nest maintenance is constrained by physiologically limiting resources. The effort of stone collection and the perceived risk of nest flooding were experimentally manipulated during the incubation and early brooding phases in a chinstrap penguin, Pygoscelis antarctica, colony. Three groups of nests were established. After weighing, control nests were left unmanipulated. In a second group of nests (reduced group), only one-half of the initial weight of stones was returned to the nests. In a third group of nests (snow-added group), we both reduced nest weight by a half and added snow outside the nest bowl over 6 consecutive days. Ten days after manipulation, the difference in nest weight between initial and final conditions was significantly related to treatment: penguins increased stone provisioning in the reduced group (44% of half-reduced nests), but drastically more in the reduced and snow-added group (123% of half-reduced nests), while the weight of control nests was unchanged compared to premanipulation conditions. The intensity of stone provisioning was affected by nest date, peaking about hatching time and shortly after, and declining with advancing chick age. These results suggest that stone provisioning is a mechanism that has evolved to prevent egg or chick mortality by nest flooding. The haematocrit, but not leukocyte numbers as expressed by the buffy coat layer, varied with the experimental conditions. Penguins investing more time in nest maintenance had a lower haematocrit, suggesting a physiological trade-off probably mediated by competition between the time devoted to nest maintenance versus foraging activities. The amount of stones collected and the haematocrit were positively related to the number of neighbour nests, so those individuals surrounded by more nests seemed to obtain benefits in the availability of nest material and energy savings. This study indicates that stone-provisioning behaviour is a nest-maintenance activity evolved to improve thermal nest characteristics potentially increasing offspring survival, and competing in time and energy with other reproductive activities. Stone provisioning in penguins should therefore be regarded as a form of parental care and an important part of individual reproductive effort in species breeding in harsh environments. Furthermore, nest size and nest-maintenance effort should be considered reproductive traits indicative of parental quality and thus could also be involved in the post-mating sexual selection process.