Climate change impacts on critical international transportation assets of Caribbean Small Island Developing States (SIDS): the case of Jamaica and Saint Lucia

This contribution presents an assessment of the potential vulnerabilities to climate variability and change (CV & C) of the critical transportation infrastructure of Caribbean Small Island Developing States (SIDS). It focuses on potential operational disruptions and coastal inundation forced by CV & C on four coastal international airports and four seaports in Jamaica and Saint Lucia which are critical facilitators of international connectivity and socioeconomic development. Impact assessments have been carried out under climatic conditions forced by a 1.5 °C specific warming level (SWL) above pre-industrial levels, as well as for different emission scenarios and time periods in the twenty-first century. Disruptions and increasing costs due to, e.g., more frequent exceedance of high temperature thresholds that could impede transport operations are predicted, even under the 1.5 °C SWL, advocated by the Alliance of Small Island States (AOSIS) and reflected as an aspirational goal in the Paris Climate Agreement. Dynamic modeling of the coastal inundation under different return periods of projected extreme sea levels (ESLs) indicates that the examined airports and seaports will face increasing coastal inundation during the century. Inundation is projected for the airport runways of some of the examined international airports and most of the seaports, even from the 100-year extreme sea level under 1.5 °C SWL. In the absence of effective technical adaptation measures, both operational disruptions and coastal inundation are projected to increasingly affect all examined assets over the course of the century.     

Dividivi tannins: an ecological product for water-based drilling fluids

Modified tannins are used as deflocculant additives in the formulation of water-based drilling fluids (WBDF) for drilling operations in any scenario. Due to their high heavy metals content, these additives are toxic and hazardous for any environmental scenario. Deflocculant efficiency of unmodified tannins (UDT) extracted from fruit pods of “dividivi” (Caesalpinia coriaria) as an additive for WBDF was assessed. Raw materials for UDT elaboration come from the rural and sustainable exploitation of natural occurring dividivi trees, growing in dry tropical forests in Anzoátegui state (Orinoco Oil Belt, eastern Venezuela). The tannins extract, in the form of dividivi fruit powder, contains 47.0 % of total tannins (hydrolyzable tannins plus condensed tannins), of which 67.4 % corresponds to hydrolyzable tannins. Dividivi tannins in WBDF showed nine (9) times deflocculant efficiency than heavy metals commercial modified tannins. Moreover, commercial modified tannins do not improve their deflocculant efficiency with increased tannin content. Ecotoxicological studies were carried out for WBDF formulations with UDT, using freshwater microalgae Scenedesmus dimorphus as chronic toxicity bioindicator. Toxicity bioassays performed with these microalgae did not show significant effects on its population growth. The EC₅₀ values resulted in over 100,000 mg L^?1, and these formulations were therefore considered non-toxic. Values of LC₅₀ obtained this time with Poecilia reticulata, as acute toxicity bioindicator are around 100,000 mg L^?1, with no significant effects on population mortality. Thus, WBDF formulated with UDT can be considered non-toxic formulations for populations of this freshwater fish. From the social perspective, the use of UDT in WBDF fosters organized communities economical activities based on the maintenance of a sustainable supply chain for processing fruits in a quantity enough to obtain three thousand seven hundred fifty kilograms (3750 Kg). The UDT so obtained was used as deflocculant in four (4) oil wells producing excellent performance and relevant savings compared with commercial modified tannin.     

Revealing the economic channels of natural impacts: an extended input–output subsystems application to GHG gases and water use

While a small set of economic activities generates most of the direct environmental burdens, the complexity of connections within an economic system requires consideration of the effects caused by the interdependences between its different agents. To date, however, the input–output (I–O) subsystems literature has been limited to uncovering the intersectoral linkages of direct and indirect environmental impacts within an economy and the connections between sectors and private consumption have thus not attracted much attention. This paper proposes an I–O subsystems model that endogenously incorporates not only production sectors but also household consumption to capture the entire channel of environmental impacts. The empirical application focuses on carbon dioxide equivalent (CO₂-eq.) emissions and water use associated with production sectors and households defined in the I–O table for a Spanish region, Extremadura. The results highlight the key role of the effects induced by private consumption on the environmental burdens of services.     

17β-Estradiol and testosterone in drainage and runoff from poultry litter applications to tilled and no-till crop land under irrigation

Thirteen metric tons of poultry litter are produced annually by poultry producers in the U.S. Poultry litter contains the sex hormones estradiol and testosterone, endocrine disruptors that have been detected in surface waters. The objective of this study was to evaluate the potential impact of poultry litter applications on estradiol and testosterone concentrations in subsurface drainage and surface runoff in irrigated crop land under no-till and conventional-till management. We conducted an irrigation study in fall of 2001 and spring of 2002. Four treatments, no-till plus poultry litter, conventional-till plus poultry litter, no-till plus conventional fertilizer, and conventional-till plus conventional fertilizer, were evaluated. Flow-weighted concentration and load ha⁻¹ of the two hormones were measured in drainage and runoff. Soil concentrations of estradiol and testosterone were measured. Based on comparisons to the conventional fertilizer (and control) treatments, poultry litter did not add to the flow-weighted concentration or load ha⁻¹ of either estradiol or testosterone in subsurface drainage or surface runoff. Significant differences were, however, observed between tillage treatments: flow-weighted concentrations of estradiol were greater for no-till than conventional-till plots of the June irrigation; and runoff loads of both estradiol and testosterone were less from no-till than conventional-till plots for the November irrigation. Although the differences between no-till and conventional-tillage appeared to affect the hydrologic transport of both hormones, the differences appeared to have inconsequential environmental impact.     

A Framework for Designing Ecological Monitoring Programs for Protected Areas: A Case Study of the Galachos del Ebro Nature Reserve (Spain)

The assessment of management effectiveness in protected areas, i.e., the evaluation of whether management strategies are actually helping to achieve stated goals, is becoming a priority. In any such evaluation, accurate information concerning the dynamics of the managed system is required—information that is gathered through monitoring. Few protected areas, however, have well-developed monitoring plans, and reserve managers are faced with a shortage of protocols for their design. This paper proposes a methodology, applicable to a wide range of situations, for designing such plans. The process begins with the precise definition of the aims of the monitoring plan, followed by the identification of key ecological processes and management objectives for the area, and finally the selection of a reduced set of indicators. These indicators are represented at three levels of growing complexity, allowing the plan to be followed in a modular fashion and in agreement with available resources.     

Influence of task demands on occupational stress: Gender differences

IntroductionOccupational stress is a common phenomenon in our society, and generates problems for both workers' health and the functioning of organizations. Over past decades numerous studies have examined occupational stress from the perspective of gender, offering somewhat contradictory results. Some of them found no differences and others indicated that either men or women suffer from greater amounts of occupational stress.MethodThe purpose of this study was to analyze gender differences in stress in situations that involve certain occupational demands. The data used were taken from a random sample population of 11,054 (5,917 men and 5,137 women) from the VI National Survey on Working Conditions (NSWC) which was conducted in Spain in 2007. To carry out this study, a probabilistic model was constructed using Bayesian networks, with the following variables related to task demands: working with tight deadlines, quick work, intellectually demanding work, complicated tasks, repetitive tasks, excessive work, and work demanding high attention levels.ResultsThe results of this study reveal that: the indicators studied significantly increased stress levels; women initially had higher stress levels than men; and when exposed to determined task demands, stress differences between genders tended to increase.Impact on IndustryCompanies need to consider the gender of their workers when assigning tasks in high demand/stress jobs.     

SIMULTANEOUS EQUATION SYSTEMS: A CONSISTENT ESTIMATOR FOR UNKNOWN PARAMETERS IN CONFINED AQUIFERS1

ABSTRACT: This paper presents criteria for establishing the identification status of the inverse problem for confined aquifer flow. Three linear estimation methods (ordinary least squares, two-stage least squares, and three-stage least squares) and one nonlinear method (maximum likelihood) are used to estimate the matrices of parameters embedded in the partial differential equation characterizing confined flow. Computational experience indicates several advantages of maximum likelihood over the linear methods.