Regional integration and local change: road paving, community connectivity, and social–ecological resilience in a tri-national frontier, southwestern Amazonia

Initiatives for global economic integration increasingly prioritize new infrastructure in relatively remote regions. Such regions have relatively intact ecosystems and provide valuable ecosystem services, which has stimulated debates over the wisdom of new infrastructure. Most prior research on infrastructure impacts highlights economic benefits, ecological damage, or social conflicts. We suggest a more integrative approach to regional integration by appropriating the concepts of connectivity from transport geography and social?Cecological resilience from systems ecology. Connectivity offers a means of observing the degree of integration between locations, and social?Cecological resilience provides a framework to simultaneously consider multiple consequences of regional integration. Together, they offer a spatial analysis of resilience that considers multiple dimensions of infrastructure impacts. Our study case is the southwestern Amazon, a highly biodiverse region which is experiencing integration via paving of the Inter-Oceanic Highway. Specifically, we focus on the ??MAP?? region, a tri-national frontier where Bolivia, Brazil, and Peru meet and which differs in the extent of highway paving. We draw on a tri-national survey of more than 100 resource-dependent rural communities across the MAP frontier and employ indicators for multiple dimensions of connectivity and social?Cecological resilience. We pursue a comparative analysis among regions and subregions with differing degrees of community connectivity to markets in order to evaluate their social?Cecological resilience. The findings indicate that connectivity and resilience have a multifaceted relationship, such that greater community connectivity corresponds to greater resilience in some respects but not others. We conclude by noting how our findings integrate those from heretofore largely disparate literatures on infrastructure. The integration of transport geography with resilience thought thus stands to advance the study of infrastructure impacts.     

Biomarker responses as indication of contaminant effects in Oreochromis niloticus

The current study investigated oxidative stress parameters (enzymes activities, metallothionein content and lipid peroxidation) in freshwater fish, Oreochromis niloticus, tilapia exposure to Monjolinho River (in 4 months of year: January, April, July and November). One critical site in Monjolinho River (site B) was assessed in comparison to a reference site (site A). Water pH and oxygen concentration was lower than that recommended by CONAMA (Brazilian National Environmental Committee), resolution 357/2005 for protection of aquatic communities, and ammonium and the metals Cu, Zn, Mn and Fe (on all months) concentrations were higher than the maximum concentration recommended. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were significantly decreased in liver and muscle in tilapia from Monjolinho River, throughout the year, in relation to reference except in gills that SOD activity increased. Glutathione S-transferase (GST) activity was significantly increased in liver of the tilapia from Monjolinho River in all sites, in relation to reference except in gills that GST activity increased in July and decreased in November, suggesting that GST activity could be induced to neutralize the pollutants toxicity. On the other hand, GST activity was significantly decreased in white muscle indicating a toxic effect of pollutants, resulting in a decreased ability of tilapia to perform defense reactions associated to GSTs. The decrease of catalase (CAT) activity in gills of the O. niloticus together with the increase of SOD activity, could explain the increased lipid peroxidation (LPO) level in this organ. Metallothionein levels in liver and gills were significantly high in all sites. Results indicate that the exposure to metals caused severe damage to tissues; despite the consensually assumed antioxidant induction as a sign of exposure to contaminants the effects seem in part to be mediated by suppression of antioxidant system with SOD, CAT and GPx as potential candidates for tissues toxicity biomarkers of pollutants.     

Assessment of metal availability to vegetation (Betula pendula) in Pb-Zn ore concentrate residues with different features

In this work, characterisation of several ore concentrate remains from an abandoned Pb-Zn mining factory was performed determining chemical and physical properties such as pH, organic carbon content, particle size distribution, total heavy metal content (Pb, Zn, Cu, As and Cd) as well as mineralogical composition which showed, in most cases, the oxidization of the parent ore material (mostly galena: PbS and sphalerite: ZnS) to more mobile fractions as anglesite (PbSO(4)) and goslarite (ZnSO(4)). Moreover, two operational defined extraction procedures commonly used in soil and sediment studies (first and second steps of BCR procedure and DTPA extraction protocol) were applied in the different mining wastes in order to study Pb and Zn mobility and likely bioavailability to Betula pendula growing on the same mining spoils, which presents lead and zinc contents in leaves over ten times background values.     

Separate collection of the biodegradable fraction of MSW: an economic assessment

There is little experience in Portugal with the separate collection of the biodegradable fraction of municipal solid waste (MSW). Therefore, it is relevant to evaluate how this process could economically affect the actual practices of MSW collection in small municipalities. This article simulates the costs of collection by means of a fixed container system and a transfer station, using values from a municipality with a population of 28,000 inhabitants. The main goal of this exercise is to compare the economic effects of three alternative scenarios: (i) the traditional, unsorted collection; (ii) the separate collection of whole biowaste; and (iii) the separate collection of biowaste generated in the major urban communities, while setting aside the other biowaste for home composting. The input data are from 2001, and include waste quantities, travel times, work crew composition, crew time shifts, vehicles, and containers. Calculations of the proposed mathematical method were carried out using the Microsoft Excel software. This study concludes that the global cost for separate collection of biowaste (alternative ii) need not necessarily be higher than the corresponding cost of the traditional, unsorted method of collection (alternative i). Furthermore, the global cost for collection with separated biowaste and home composting (alternative iii) could also be lower than the corresponding cost of the traditional, unsorted method of collection.     

Effect of nitrogen amendment on respiration and respiratory quotient (RQ) in three hydrocarbon contaminated soils of different type

Three soil types (sandy gravel, silty clay and sandy loam) from sites historically contaminated with total petroleum hydrocarbon (TPH) were amended with NH(4)NO(3) at concentrations ranging from 16 to 2133 mg/kg soil(dry weight). Microbial activity was measured as O(2) consumption and CO(2) production in order to assess nitrogen limitation. Although activity was stimulated in all three soils under NH(4)NO(3) amendment (after 72 h), the level of nitrogen required was soil specific. For the sandy gravel and silty clay soils, O(2) consumption and CO(2) production both showed enhanced microbial activity when amended with 16 mg/kg soil(dry weight) NH(4)NO(3), whereas, these two parameters gave differing results for the sandy loam soil. Specifically, CO(2) production and O(2) consumption were stimulated with 66 mg/kg and 133 mg/kg soil(dry weight) of NH(4)NO(3) respectively. In addition, respiratory quotient kinetic analysis suggested different decomposition processes occurring in this soil under different NH(4)NO(3) amendment concentrations.     

Aromatic/Aliphatic Polyester Blends

Blends of poly(3-hydroxybutyrate) (PHB) and poly(ethylene terephthalate-co-1,4-cyclohexenedimethanol terephthalate) (PETG) were prepared in a batch mixer and in a twin screw extruder and characterized by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), field emission scanning electron microscopy (FE SEM), flexural tests, biodegradation tests in soil compost and in an enzymatic medium. The torque data showed that the addition of PETG to PHB improved its processability. DSC, DMA and FE SEM showed that the polymers are immiscible with morphology dependent on the processing conditions. A fine dispersion of PETG in the PHB matrix was observed for extruded and injection molded blends. Flexural modulus for blends was higher for blends in comparison with PHB, while the impact resistance of blends containing 20 wt% and 30 wt% of PETG is comparable to the value for PHB. PHB is biodegradable, while PETG did not degrade either in simulated soil or in the α-amylase medium. On the other hand, the PHB phase of the blends degrades under these aging conditions. Thus, the addition of PETG to PHB results in advantage such as improving of processability and Young′s modulus without significant changes in the impact resistance while keeping the biodegradability of PHB.     

Overcoming the blame game to learn from major accidents: A systemic analysis of an Anhydrous Ammonia leakage accident

This article aims to demonstrate the need for changing the methods with which accidents are analyzed, if we truly wish to use what we uncover from them to learn and enrich our knowledge base of organizational management. The goal is to relinquish the broadly adopted and rather simplistic paradigm that accepts the search for human error and unsafe acts performed by workers, and produces “guilt diagnostics”. Instead, we use a systemic accident analysis methodology, based on the sociotechnical principle of understanding the real operating conditions in which accidents take place. In order to demonstrate the benefits of the theoretical framework, we compare the analyses of an Anhydrous Ammonia gas leakage accident in a fish processing plant using the traditional accident analysis model based on unsafe acts and the proposed systemic approach. The results favor the latter since it tends to be more reliable and offering useful recommendations to safety management processes, thus helping to prevent accidents, especially in complex systems.     

Effects of widely used pharmaceuticals and a detergent on oxidative stress biomarkers of the crustacean Artemia parthenogenetica

Pharmaceuticals are continuously dispersed into the environment as a result of human and veterinary use, posing relevant environmental concerns. The present paper reports the acute toxic effects of three therapeutic agents (diazepam, clofibrate and clofibric acid) and a detergent, sodium dodecylsulphate (SDS), to the hypersaline crustacean Artemia parthenogenetica. This study specially focused on oxidative stress parameters, namely (1) total and selenium-dependent glutathione-peroxidase (GPx), (2) glutathione reductase (GRed), (3) total superoxide dismutase (SOD), and (4) glutathione-S-transferases (GSTs). The effects of tested substances on lipid peroxidation (thiobarbituric acid reactive substances, TBARS), and soluble cholinesterases (ChE) were also investigated. Diazepam caused a significant inhibition of ChE (LOEC = 7.04 mg/l) and total GPx activities. SDS was responsible for a decrease in the activity of both ChE (LOEC = 8.46 mg/l) and GRed (LOEC = 4.08 mg/l). Both fibrates (clofibrate and clofibric acid) were responsible for significant decreases in Se-dependent GPx, with LOEC values of 176.34 and 3.09 mg/l, respectively. Clofibrate also caused a slight increase of TBARS content of A. parthenogenetica homogenates. These results indicate that the exposure to all the tested compounds induced alterations on the cellular redox status in A. parthenogenetica. In addition, diazepam was shown to have the capability of interfering with A. parthenogenetica neurotransmission, through the inhibition of ChE.     

Association between occupational exposure to domestic solid waste and dental caries: a cross-sectional study

Environmental Science and Pollution Research - Studies have shown that domestic waste collectors are exposed to toxicants including infectious pathogens, which may be linked to their oral health...