Persistence of airline accidents

This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927–2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non‐stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long‐run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation.     

Numerical Modeling of the Impact of a Pumped-Storage Hydroelectric Power Plant on the Reservoirs’ Thermal Stratification Structure: a Case Study in NW Spain

Pumped-storage hydroelectric power plants are generally perceived as an environmentally respectful technology. Nevertheless, the pumping of water from a lower reservoir to an upper impoundment, and the return of that water during power generation, can strongly affect the water quality of the reservoirs. In particular, plant operation can alter their thermal structure, deep water mixing, and water circulation characteristics. The objective of this study is to quantify, through the use of 3D hydrodynamic modeling, the potential impacts of a pumped-storage hydroelectric plant on the thermal stability and mixing of two reservoirs in Galicia, northwest of Spain. To this end, three-dimensional hydrodynamic simulations were conducted using the model Delft3D. Two different coupled models, one for each reservoir, were constructed and subsequently tested for several stratification scenarios, according to measured temperature profiles during the spring and summer season. Several reservoir minimum and maximum operation water levels were also considered. Model simulations demonstrated a high level of mixing in the vicinity of the intake-outlet structures, in particular during startup of the power plant, regardless of the water level in the reservoir. Beyond this area, the results showed a limited overall effect on stratification and mixing in the upper reservoir, owing to the relation between the inflow temperatures and the initial temperature profile of this reservoir. A more significant alteration of the thermal structure is expected in the lower reservoir due to its narrow shape and shallow depth at the structure location, as well as the temperature differences between receiving waters and inflow.     

Ivermectin dissipation and movement from feces to soil under field conditions

The aim of this work was to evaluate the fate of ivermectin (IVM) at two concentrations in cattle feces and its movement to the nearby soil and plants. Feces were spiked with IVM at two levels: 3000 ng g^?1 (high group, HG) and 300 ng g^?1 (low group, LG). Artificial dung pats were prepared and deposited in an experimental field area. Feces and underlying soil were sampled up to 60 days post-deposition (dpd). As an additional analysis, grasses growing around the pats were sampled at 30 and 60 dpd. Ivermectin concentrations in all matrices were determined by HPLC. Mean IVM fecal concentrations were in the range between 3901.9 ng g^?1 and 2419.2 ng g^?1 (high group) and 375.3 ng g^?1 and 177.49 ng g^?1 (low group). Mean times for 50% and 90% dissipation were 88.23 and 293.03 days (HG) and 39.1 and 129.9 days (LG). Soil concentrations ranged from 26.1 ng g^?1 to 71.1 ng g^?1 (HG) and 3.4 to 5.9 ng g^?1 (LG); in plants, concentrations were between 71.4 and 380.8 ng g^?1 and 5.40 and 51.8 ng g^?1 in HG and LG, respectively. These results confirm that IVM moves from feces to the underlying soil as well as to nearby plants. The potential risk of detrimental effects on soil organisms and the impact on herbivorous animals should be further evaluated.     

Effects of beach tourists on bathing water and sand quality at Puerto Velero,Colombia

Fragile coastal areas suffer from human activities. Environmental quality is one of the most important aspects in a tourist destination of sun and sand. The quality of bathing water and sand became indicators in the worldwide competition of beach destinations. We studied the water and sand quality along the beach of Puerto Velero, in northern Colombia. Water and sand beach quality were monitored during thirteen months. This allowed identifying the most significant sources of pollution along the beach, and understanding the interrelationship between tourism and the effects on the environment. Linear correlations allow assessing the association between the number of visitors and the physicochemical and microbiological parameters. The number of visitors was directly correlated with the presence of grease and oils, both in water and sand, as well as with fecal coliforms in water. A relation between the suspended solids and the presence of fecal coliforms in water and sand was observed. This statistical approach allows understanding the origin of beach sand and swimming water pollution at tourist beaches. Overall, sand quality has an important influence and is directly related to the water quality of the beach. Both the number of tourists and their activities are main factors explaining the contamination of the water and sand. This shows the importance of management of waste and wastewater in combination with awareness raising initiatives. More research should include monitoring and evaluating of both water and sand beach and provide data to revise the existing legal framework.     

Land cover effects on water balance partitioning in the Colombian Andes: improved water availability in early stages of natural vegetation recovery

Regional Environmental Change - Vegetation actively affects different components of the water budget in multiple spatial and temporal scales. Changes in vegetation cover and structure—such as...     

Take Action Now: Motivational Framing and Action Requests in Climate Advocacy

This article explores similarities and differences between Internet-mediated climate change advocacy organizations and their legacy counterparts. It relies on a content analysis of advocacy emails produced by Environmental Defense Fund, Natural Resources Defense Council, Sierra Club, Greenpeace USA, League of Conservation Voters, Climate Reality Project, 1Sky, and 350.org. The study finds differences and similarities in strategic Internet use, including greater emphasis by climate groups on high threshold, offline actions; greater emphasis by legacy groups on low threshold, online actions; and high reliance by both framings that demand accountability from political elites. Implications for Internet-mediated and climate advocacy are discussed.     

Are children playgrounds safe play areas? Inorganic analysis and lead isotope ratios for contamination assessment in recreational (Brazilian) parks

Environmental Science and Pollution Research - In city playgrounds, there is a potential risk of harming children’s health by contamination coming from anthropogenic activities. With the aim...     

Wind energy in the Isthmus of Tehuantepec: conflicts and social implications

Social acceptance is fundamental, and directly affects the installation of wind farms. In this paper, the factors that have had the greatest influence on the development of wind energy in the Itsmo region of Tehuantepec, Mexico are identified. The data were collected face to face through a semi-structured questionnaire of 31 people: owners, municipal authorities, opposition groups, and academic members. The results of the interview highlight the social impact, the lack of application, and concerning ILO Convention 169, the abuse of community rights. As a result, people interviewed perceive that the environmental impact of the installation, and operation of wind farms has been ambivalent: positive due to the intrinsic benefits that wind energy generates compared to other energy sources, and negative in terms of affectation by the noise, and the landscape. However, the income received by the owners of land in which wind facilities are located is lower compared to other parts of the world. In general, the facts show a disintegration between the authorities (federal, state, and municipal), universities are isolated from wind projects, communities are not consulted in projects, and large companies are the main beneficiaries.

     

Recreation benefits of natural area characteristics at the El Yunque National Forest

The paper applies the Contingent Valuation Method using a visitor survey to determine trip values to three rivers in northeastern Puerto Rico. Sample data were obtained from 984 interviews conducted in 13 sites during the summer months. The trip value is statistically decomposed into components representing natural features and recreation activities. The median net economic value of a river visit without waterfalls or foot trails is $96. Recreation at rivers with both waterfalls and foot trails has a median value of $138 per trip. The presence of waterfalls accounts for $23 and foot trails $19 per trip. This information can be pertinent for managers in selecting recreation site locations and protecting them from competing uses.