Using Vegetation Analysis to Facilitate the Selection of Conservation Sites in Eastern Paraguay

This study demonstrates the use of vegetation analysis in the selection of priority areas for conservation. The analysis is based on field data derived from narrow rectangular sample plots and includes information from the database of Paraguay's Conservation Data Center. Ten 100-m² sample plots were laid out for each survey site. We compared three sites, Mbaracayú, Tarumá, and Parabel, all forests located in the ecoregion of Selva Central in eastern Paraguay. Subtropical and physiognomically similar, the sites are dominated by a single species, either Sorocea bonplandii or Actinostemon concolor , but differ in species richness. Vegetation analysis permitted us to calculate the total number of species, including liana species, the number of economic plants, and the number of rare, uncommon, and vulnerable species, and thus to quantify the conservation worthiness of the candidate sites. Our study pinpoints Mbaracayú as a mature, resource-rich forest with the highest habitat and plant species diversity and several local endemics. We maintain that it is the area of Paraguay's Selva Central most important for conservation.     

Design-based ranked set sampling using auxiliary variables

A ranked set sampling protocol is proposed when an auxiliary variable is available in addition to the target variable in sample surveys. The protocol may be practically carried out without additional sampling effort or costs. Under the suggested sampling scheme, the estimators usually adopted in surveys with auxiliary information - such as the ratio estimator or the regression estimator - display surprising theoretical properties as well as high performance in practice.     

Species abundance estimation using point-to-plant sampling in a design-based setting

A new species abundance estimator is proposed when point-to-plant sampling is adopted in a design-based framework. The method is based on the relationship between each species abundance and the probability density function of the relative squared point-to-plant distance. Using this result, a kernel estimator for species abundance is provided and the nearest neighbor method is suggested for bandwidth selection. The proposed estimator requires no assumptions about the species point patterns nor corrections for sampling near the edges of the study region. Moreover, the estimator shows suitable statistical properties as well as good practical performance as is shown in a simulation study.     

Gathering new knowledge from existing monitoring dataset of Campania marine coastal area (Southern Italy)

Environmental Science and Pollution Research - In this study we propose, a multi-step strategy of selection and characterization of long-term dataset of contaminant concentrations in different...     

Modeling the binding of triazine herbicides to humic substances using capillary electrophoresis

The binding of 4 s-triazines herbicides and metabolites, ameline, hydroxyatrazine, atraton, and ametryn to 12 structurally different humic substances was studied by affinity capillary electrophoresis. Binding data were confronted to the structural data of humic acids obtained from spectrometric measurements (UV-Vis, FT/IR, NMR), elemental analysis and potentiometric titration. The results obtained with principal component analysis and partial least square analysis clearly show the importance of carboxylic acidity and aromaticity of the humic ligands in relation to the partial positive charge and relative hydrophobicity of the pesticides.     

OPTIMIZATION OF TRANSPORTATION NETWORKS DURING URBAN FLOODING1

ABSTRACT: In this paper a numerical model for flood propagation in urban areas is proposed. It has been applied to evaluate flooding hydraulic characteristics in terms of potential flood elevations, depths, and inundated areas. Furthermore, the algorithm efficiency and the consequent reduced computation time allow the use of the hydraulic model as a part of a more complex system for civil protection actions, planning, and management. During flood events, the transportation network plays a main role both in rescuing people when they are more vulnerable and in moving people and materials from and toward affected areas. The reduced efficiency of this transportation network is evaluated based on a least‐flood‐risk path‐finding algorithm. The results of a case study concerning the northern part of the city of Rome, show that the numerical model for unsteady flow in open channel networks achieves the proposed aims. It has proven to be able to describe the flood hydraulic characteristics and to be suitable for real‐time flood emergency management in urban areas.     

Monitoring Nitrogen Dioxide and its Effects on Asthmatic Patients: Two Different Strategies Compared

Objectives: To develop a `methodologyassessment' to evaluate the strengths and theweaknesses of two different epidemiological approachesand to identify the best suited monitoring strategy tomeasure the effects of `normal levels' of nitrogendioxide exposure on the health of an urban population.Methodology: all exposures to nitrogen dioxidewere determined with passive samplers, each samplerconsisting of 3 measuring Palmes tubes. In the firststudy the nitrogen dioxide exposure was assessed in 23school children (11 asthmatic and 12 non asthmatic).Children wore samplers for a week and parallelmeasurements were made in their kitchens, in bedroomsand outside their homes. The second study consisted ina case-control study where the relative risk ofhospital admission was calculated considering nitrogendioxide levels in a city of northern Italy. 110asthmatic patients were compared to a control group of 5322 people.Results: Personal sampler measurementshighlighted significant differences in exposure when nitrogen dioxide atmospheric levels were compared inasthmatic and healthy children (p<0.05). No otherparameters were significant in the two groups. Asignificant action of atmospheric nitrogen dioxide onhospital admission was demonstrated (p<0.01).Conclusions: Although a cause-effect relation assuch cannot be identified, the studies show a relationbetween the exposure to nitrogen dioxide and thepresence of adverse effects on people's health.However the `disadvantage' is for subjects withasthmatic pathologies, compared to the others. Tomanage this problem most effectively, a combinedapproach with the activation of specific personalmonitoring campaigns of the subjects with verifiedrisk seems necessary. This requires `reading' the dataresulting from most extensive and up to dateinformation systems, capable of a thorough controlboth of the living environment and of the clinicaloutcome of the whole population.     

Tar removal during the fluidized bed gasification of plastic waste

A recycled polyethylene was fed in a pilot plant bubbling fluidized bed gasifier, having an internal diameter of 0.381 m and a maximum feeding capacity of 90 kg/h. The experimental runs were carried out under various operating conditions: the bed temperature was kept at about 850 degrees C, the equivalence ratio varied between 0.2 and 0.35, the amount of bed material was between 131 and 215 kg, the fluidizing velocity was between 0.5 and 0.7 m/s, quartz sand and olivine were used as bed material, and air and steam were used as fluidizing reactants. The results confirm that the tar removal treatments applied inside the gasifier (primary methods) can eliminate or strongly reduce the need for a further downstream cleanup of the syngas. In particular, the utilization of a natural olivine as an in situ tar reduction agent remarkably improves the quality of the product gas, in terms of both high hydrogen volumetric fraction and larger syngas yield.