Vulnerability of biological resources to potential oil spills in the Lower Amazon River, Amapá, Brazil.

Ships that transport oil or derivatives on the Lower Amazon River waterway are at a considerably high risk of suffering spills, with severe environmental and socioeconomic consequences. The present study is aimed at modeling and simulating the oil dispersion and magnitude of these accidents in terms of the vulnerability of biological resources, considering two oil types most often transported by medium-sized tankers in the region (S500 and S10). The study method was as follows: (a) secondary data were collected from local species, and the coastal sensitivity index (CSI) was calculated, obtained from Brazil's Letters of Environmental Sensitivity to Oil Spill (Cartas de Sensibilidade Ambiental ao Derramamento de Óleo (SAO)); (b) ship traffic information was obtained from Brazil's Statistical Yearbook of Waterway (Anuário Estatístico Aquaviário (ANTAQ)); (c) modeling and numerical simulation of oil spills in water were performed, in order to investigate dispersion scenarios (SisBaHia); (d) three numerical scenarios of oil plume dispersion (in May and November) were integrated to assess species vulnerability in three zones of environmental interest (I, II, and III). Some species identified in zone II were considered to be the most vulnerable (fish, plankton, aquatic mammals, amphibians, aquatic invertebrates, trees, and plants), with the mammal Sotalia fluviatilis being at risk of extinction (Gervais & Deville, 1853). The simulated scenarios showed that contingency plans should have a minimum response time of 3 h and a maximum response time of 72 h to prevent the oil plumes from dispersing as far as 170 km longitudinally, depending on the zone, season, and tidal phase. Thus, a total of 62 sites of biological resources were identified in the literature recorded from 2016. Considering them, 324 species of flora and fauna were recorded, distributed in the following seven groups: (i) 49 tree and plant species, (ii) 37 amphibian species, (iii) 2 aquatic invertebrate species, (iv) 23 invertebrate species, (v) 1 aquatic mammal species, (vi) 95 fish species, and (vii) 117 planktonic species. A failure to respond to these accidents would impact immense intact aquatic areas and ecosystems, with unpredictable consequences for local biodiversity conservation.

Solid waste generation indicators, per capita, in Amazonian countries.

Countries participating in the Amazon Cooperation Treaty Organization have few options for the environmentally appropriate final disposal of municipal solid waste. Thus, sustainable practices aimed at reducing the negative effects of such a disposal on the environment are complex and hard to accomplish, since solid waste generation per capita proportionally increases as populations grow (≈ 2.7% > world average), mainly in countries inserted in Amazon Cooperation Treaty Organization. Thus, demographic, socioeconomic, management, and ecological factors represented by 18 independent variables were statistically analyzed to explain waste per capita variation in Amazonian countries and sub-regions. Multiple Kruskal-Wallis tests were applied; 13 of them recorded significant results (p < 0.05). Subsequently, simple and multivariate regression analyses were carried out by taking into consideration waste per capita and significant variables. Simple regression results recorded for variables "IAC" and "Gini index" were significant (RIAC2 = 60.09%, RGini2 = 30.83%), with emphasis on "Amazon biome" (DF = 33, p < 0.01, RBiome2 = 5.34%). Multivariate models resulted in wide explainability variation, depending on the number and type of available variable (54.47% ≤ Raj2 ≤ 70.83%), with emphasis on "IAC," "Ptot," "Purb," "Wton," "Lon," Area, "HDI," "Gini," and "SDG11" (p < 0.01). In conclusion, waste per capita estimation models can present variations and geographical interdependencies due to different variables and factors that reflect the current public policies and municipal solid waste management practices.

Modeling pollutant dispersion scenarios in high vessel-traffic areas of the Lower Amazon River.

Large ships are efficient in transporting oil and its derivatives. However, they can cause spills in the event of accidents. The aim of the study is to simulate oil dispersion processes in scenarios of likely accidents with ships traveling on sea routes interconnected with Amazonian ports and with the Atlantic Ocean. Navigation routes were based on traffic data to identify risk areas, as well as to compare them to data from the environmental (oil) sensitivity index and to results of numerical simulations of plumes dispersion. These three approaches were integrated to each other in order to assess potential environmental impacts of plumes on coastal biota and human populations. Scenarios results have indicated that the rainy season is the most critical period for plumes dispersion. But, depending on the emission point, plumes tend to remain close to the coast, extend up to 132 km within 72 h, affecting the biodiversity, protected areas and water supply systems from the urban areas.

Distribution pattern of crustacean ectoparasites of freshwater fish from Brazil.

The purpose of this study was to use the informations relating to parasite crustaceans species that was published over the course of one century (1913 to 2013), in order to search for infestation and distribution patterns among these ectoparasites in Brazilian freshwater fish species. This search was carried out on 445 samples of 119 host fish of 27 families within the orders Characiformes, Perciformes, Clupeiformes, Mugiliformes, Osteoglossiformes, Symbranchiformes, Tetraodontiformes and Siluriformes from various regions of Brazil. We organized different host-parasite systems into matrices grouping species at different taxonomic and infestation levels and according to host parameters. Five families of parasites (Ergasilidae, Argulidae, Lernaeidae, Lernaeopodidae and Cymothoidae) distributed into 76 species of 27 genera were analyzed in the host samples, which presented dominance of Ergasilidae species, mainly from the genus Ergasilus. Some crustaceans are host and site-specific, especially in relation to fish in particular habitats and lifestyles (e.g. Perulernaea gamitanae, Anphira branchialis and Riggia paranensis), while other parasites frequently have no preference (e.g. Lernaea cyprinacea and Braga patagonica). We found broadly similar distribution patterns for some crustacean species among the different localities, whereas other species showed well-defined geographical patterns, and these findings were discussed.

Ballast water: a threat to the Amazon Basin.

Ballast water exchange (BWE) is the most efficient measure to control the invasion of exotic species from ships. This procedure is being used for merchant ships in national and international voyages. The ballast water (BW) salinity is the main parameter to evaluate the efficacy of the mid-ocean ballast water exchange. The vessels must report to the Port State Control (PSC), via ballast water report (BWR), where and how the mid-ocean BWE was performed. This measure allows the PSC to analyze this information before the ship arrives at the port, and to decide whether or not it should berth. Ship BW reporting forms were collected from the Captaincy of Santana and some ships were visited near the Port of Santana, located in Macapá (Amazon River), to evaluate the BW quality onboard. We evaluated data submitted in these BWR forms and concluded that the BWE efficacy might be compromised, because data contained in these BWR indicate that some ships did not change their BW. We found mistakes in filling the BWR forms and lack of information. Moreover, these ships had discharged BW with high level of salinity, Escherichia coli and total coliforms into the Amazon River. We concluded that the authorities of the Amazon Region need to develop more efficient proceedings to evaluate the ballast water reporting forms and BW quality, as there is potential risk of future invasion of exotic species in Brazilian ports.