Violence in environmental conflicts: the need for a multidimensional approach

Although studies on environmental conflicts have engaged with the subject of violence, a multidimensional approach has been lacking. Using data from 95 environmental conflicts in Central America, we show how different forms of violence appear and overlap. We focus on direct, structural, cultural, slow, and ecological forms of violence. Results suggest that the common understanding of violence in environmental conflicts as a direct event in time and space is only the tip of the iceberg and that violence can reach not only environmental defenders, but also communities, nature, and the sustainability of their relations.     

Antiestrogenic activity of anthropogenic and natural chemicals

A number of natural and man-made chemicals possess antiestrogenic activity, i.e. they antagonize a broad spectrum of estrogen-induced responses in vertebrates. Examples of antiestrogens include dioxin, furan and PCB congeners, certain PAHs, pesticides and indol-3-carbinol derivatives. Major mechanisms of antiestrogenicity are antagonistic action of chemicals at the estrogen receptor, or binding of chemicals to the arylhydrocarbon (Ah) receptor and subsequent interaction with estrogen-responsive genes. Toxicological consequences resulting from antiestrogenic activity have not been conclusively demonstrated to date, although antiestrogenic compounds could critically affect sensitive reproductive and developmental processes.     

Influence of RFID tags on recyclability of plastic packaging

The use of Radio Frequency IDentification Technology (RFID) in the packaging sector is an important logistical improvement regarding the advantages offered by this technology in comparison with barcodes. Nevertheless, the presence of these devices in plastic packaging, and consequently in plastic waste, can cause several problems in the recycling plants due to the materials included in these devices.In this study, the mentioned recycling constraints have been experimentally identified in a pilot scale recycling study consisting in three recycling tests with an increasing presence of RFID tags. Differences in each test were evaluated. Furthermore, the quality of the recycled material of each test was studied through the injection and testing of tests probes.The results of the pilot scale recycling tests did not show a decrease in the quality of the recycled plastic due to the presence of RFID tags. Nevertheless, several operational problems during the recycling process were observed such as the obstruction of the screens, which lessened the process yield and created process interruptions, as well as the loss of extruded plastic during the process.These recycling constraints cannot be directly extrapolated to the industrial plants due to the different working scales. Nevertheless, technological solutions are proposed in order to avoid these recycling constraints if they appear.     

Time-Consistent Equilibria in Common Access Resource Games with Asymmetric Players Under Partial Cooperation

Given a differential game, if agents have different time preference rates, cooperative (Pareto optimum) solutions obtained by applying Pontryagin’s maximum principle become time inconsistent. We derive a set of dynamic programming equations in continuous time whose solutions are time-consistent equilibria for problems in which agents differ in their utility functions and also in their time preference rates. The solution assumes cooperation between agents at every time. Since coalitions at different times have different time preferences, equilibrium policies are calculated by looking for Markov (subgame perfect) equilibria in a (noncooperative) sequential game. The results are applied to the study of a cake-eating problem describing the management of a common property exhaustible natural resource. The extension of the results to a simple common property renewable natural resource model in infinite horizon is also discussed.     

Ecotoxicological effects of metal pollution in two mollusc species from the Spanish South Atlantic littoral

Metal accumulation and some of their biochemical effects have been studied in oysters (Crassostrea angulata) and mussels (Mytilus galloprovincialis) of the South Atlantic Spanish littoral. Especial attention has been paid to antioxidant defences and oxidative damage to biomolecules. Deep differences in the response of oysters and mussels to metal pollution were found. Oysters, with the higher metal loads of both species, showed increased antioxidant defences, and less extensive oxidative damage. In contrast, mussels, which accumulated much lower metal concentrations, showed clear increases in oxidized biomolecules, in agreement with their low increases in the antioxidant defence mechanisms. Our results suggest that mussels are more sensitive and less well adapted to metal pollution, probably explaining their absence in the most contaminated studied site, Mazagón. We conclude that oysters can be used as more sensitive bioindicator of pollution in the South Spanish littoral, and as a suitable model to study the adaptation to metal pollution.     

Mountain spa rehabilitation improved health of patients with post-COVID-19 syndrome: pilot study

Environmental Science and Pollution Research - European Association of Spa Rehabilitation (ESPA) recommends spa rehabilitation for patients with post-COVID-19 syndrome. We tested the hypothesis...     

Geochemical speciation of heavy metals in semiarid soils of the central Ebro Valley (Spain)

This study describes the chemical speciation of Fe, Mn, Zn and Cr in four selected soil types representative of the more abundant agricultural soils in the central Ebro river valley in Aragón. Gypsisols, Calcisols, Solonchaks and Solonetzs represent around 20% of the total soil surface in the region. A total of 12 selected sites have been sampled and five subsamples were taken in each site to create a composite sample. The four elements have been analysed by the sequential extraction procedure of Tessier et al. [Anal. Chem. 51 (1979) 844.] by emission atomic spectrometry of solid state (ICP OES). Very little amounts of Fe and Mn were retrieved from the exchangeable phase, the ready available for biogeochemistry cycles in the ecosystems. Therefore, low quantities of Fe and Mn can be taken up by plants in these alkaline soils. Cr was not detected in the bioavailable forms as well as Zn that was only present in negligible amounts in very few samples. The absence of mobile forms of Cr in all soils eliminates the toxic risk both in the trophic chain and from its migration downwards the soil profile. The largest contents of Fe, Zn and Cr were retrieved from the residual phase where metals are strongly bound to minerals, whereas Mn from the carbonate and oxide phases amounts 80% of its total content. Gypsisols and Calcisols have the lowest metal contents while the highest are found in Solonetzs and Solonchaks.     

Ecotoxicological Assessment of the Impact of Residual Heavy Metals on Soil Nematodes in the Guadiamar River Basin (Southern Spain)

On 25 April 1998, as a consequence of the breaking of a dam containing the tailings of a pyrite mine, a land strip of approximately 43 km in length was covered with a layer of black sludge, containing high levels of heavy metals, along the Guadiamar River Basin (southern Spain). In this investigation we carried out an ecotoxicological assessment (field and laboratory studies) of the impact of residual heavy metals (Cu, Pb, Zn, Ni) on soil nematodes in the impacted riparian zone, two years after the huge mine spillage. Concentrations of residual heavy metals were significantly (P<0.05) higher at the impacted sampling sectors (S-2, S-3, S-4, S-5) than at the unpolluted (reference) sampling sector (S-1). Nickel however exhibited the lowest increases at the impacted sectors. As a consequence, correlation coefficients between concentrations of heavy metals and values of ecological indices were not significant for Ni. In contrast, copper, lead and zinc exhibited significant (P<0.05) negative correlation coefficients with ecological indices, particularly with diversity indices (including the~number of taxa). In addition, the toxicity of Cu and Pb to nematode test species (Aphelenchus avenae and Cephalobus persegnis) during short-term toxicity bioassays was much higher than the toxicity of Zn and Ni. We conclude that residual heavy metals were still influencing adversely the community of soil nematodes in the impacted riparian zone of the Guadiamar River Basin. Cu, Pb and, to a lesser extent, Zn would be major responsible for the observed impact.     

Medusa buds on Eirene elliceana gonads (Leptomedusae,Eirenidae)

The Indo-Pacific leptomedusa Eirene elliceana (Agassiz and Mayer, 1902) is known to produce blastostyles budded from the gonads of the adult medusa. Three specimens out of 5, taken during the International Indian Ocean Expedition (IIOE) in the Bay of Bengal, showed medusa buds growing on young gonads whose sex could not be determined. The new findings are illustrated.Contribution No. 320 of the Instituto Oceanográfico da Universidade de São Paulo, S. Paulo, Brazil.     

Halistaura bruuni sp. nov. (Leptomedusae,Mitrocomidae) with notes on its distribution and ecology

A new hydromedusa collected in 1963 in the Bay of Bengal during the International Indian Ocean Expedition by the RV Anton Bruun is here described as Halistaura bruuni sp. nov. Some environmental data are given. The new species is characterized by a number of open marginal vesicles approximately equal to that of the tentacles, oval gonads on the distal half of the radial canals, and by the presence of nematocyst depots in the tentacle bulbs.Publ. No. 273 of the Instituto Oceanográfico da U. S. P.