A systems approach to modeling Community-Based Environmental Monitoring: a case of participatory water quality monitoring in rural Mexico

Community-Based Environmental Monitoring (CBM) is a social practice that makes a valuable contribution to environmental management and construction of active societies for sustainable future. However, its documentation and analysis show deficiencies that hinder contrast and comparison of processes and effects. Based on systems approach, this article presents a model of CBM to orient assessment of programs, with heuristic or practical goals. In a focal level, the model comprises three components, the social subject, the object of monitoring, and the means of action, and five processes, data management, social learning, assimilation/decision making, direct action, and linking. Emergent properties were also identified in the focal and suprafocal levels considering community self-organization, response capacity, and autonomy for environmental management. The model was applied to the assessment of a CBM program of water quality implemented in rural areas in Mexico. Attributes and variables (indicators) for components, processes, and emergent properties were selected to measure changes that emerged since the program implementation. The assessment of the first 3 years (2010–2012) detected changes that indicated movement towards the expected results, but it revealed also the need to adjust the intervention strategy and procedures. Components and processes of the model reflected relevant aspects of the CBM in real world. The component called means of action as a key element to transit “from the data to the action.” The CBM model offered a conceptual framework with advantages to understand CBM as a socioecological event and to strengthen its implementation under different conditions and contexts.     

Integration of Land-Sharing and Land-Sparing Conservation Strategies Through Regional Networking: The Mesoamerican Biological Corridor as a Lifeline for Carnivores in El Salvador

Nations with little remaining natural habitat and small extent are challenged when trying to achieve biodiversity targets. We show that the Central American nation of El Salvador cannot viably sustain populations of 87 % of its extant carnivores, especially in the case of large-bodied species with low population densities. Current land-sparing strategies will not suffice; therefore we propose that land-sharing strategies be implemented in tandem with protected areas to expand current conservation efforts via new regional networks. In Central America such a network can be established by linking international protected area systems in a way that implements the existing vision for the Mesoamerican Biological Corridor. Specifically, we propose a re-envisioning of the Mesoamerican Biological Corridor in which land-sharing practices are adopted throughout the agricultural matrix while ensuring formal protection of the remaining natural habitat. Such an integration of land-sparing and land-sharing could result in the creation of an effective network of protected areas, thereby increasing the probability of safeguarding species with populations that overlap national borders.     

Improvement of health risk factors after reduction of VOC concentrations in industrial and urban areas

After reductions of fugitive and diffuse emissions by an industrial complex, a follow-up study was performed to determine the time variability of volatile organic compounds (VOCs) and the lifetime cancer risk (LCR). Passive samplers (3 M monitors) were placed outdoors (n?=?179) and indoors (n?=?75) in industrial, urban, and control areas for 4 weeks. Twenty-five compounds including n-alkanes, cycloalkanes, aromatics, chlorinated hydrocarbons, and terpenes were determined by GC/MS. The results show a significant decrease of all VOCs, especially in the industrial area and to a lesser extent in the urban area. The median outdoor concentration of benzene in the industrial area declined compared to the former study, around 85 % and about 50 % in the urban area, which in the past was strongly influenced by industrial emissions. Other carcinogenic compounds like styrene and tetrachloroethylene were reduced to approximately 60 %. VOC concentrations in control areas remained nearly unchanged. According to the determined BTEX ratios and interspecies correlations, in contrast to the previous study, traffic was identified as the main emission source in the urban and control areas and showed an increased influence in the industrial area. The LCR, calculated for benzene, styrene, and tetrachloroethylene, shows a decrease of one order of magnitude in accordance to the decreased total VOC concentrations and is now acceptable according to values proposed by the World Health Organization.     

Adaptive Capacity of Fishing Communities at Marine Protected Areas: A Case Study from the Colombian Pacific

Departing from a theoretical methodology, we estimate empirically an index of adaptive capacity (IAC) of a fishing community to the establishment of marine protected areas (MPAs). We carried out household surveys, designed to obtain information for indicators and sub-indicators, and calculated the IAC. Moreover, we performed a sensitivity analysis to check for robustness of the results. Our findings show that, despite being located between two MPAs, the fishing community of Bazán in the Colombian Pacific is highly vulnerable and that the socioeconomic dimension of the IAC constitutes the most binding dimension for building adaptive capacity. Bazán is characterized by extreme poverty, high dependence on resources, and lack of basic public infrastructure. Notwithstanding, social capital and local awareness about ecological conditions may act as enhancers of adaptive capacity. The establishment of MPAs should consider the development of strategies to confer adaptive capacity to local communities highly dependent on resource extraction.     

A probabilistic model for the carry-over of PCDD/Fs from feed to growing pigs

When food producing animals are contaminated with PCDD/F congeners, information on the contaminant’s concentration in the bodies of the animals at time of slaughter is needed for risk management purposes. We have developed a mathematical model for the kinetics of PCDD/Fs in growing pigs in case of contaminated feed fed for a limited duration of time. This model allows the prediction of concentrations in body fat. It considers absorption fractions of PCDD/Fs, clearance by metabolism, dilution by growth and excretion through fecal fat. The model parameters were calibrated by fitting the model to experimental data. On the basis of this toxicokinetic model a probabilistic model has been constructed. The probabilistic model handles the parameters with appropriate probability distributions and Monte-Carlo simulation technique, providing for realistic situations with many animals and a range of contaminations and feeding intervals. We applied the new model to describe the German dioxin incident of winter 2010/2011 and discuss its viability as decision tool. The approach demonstrated here is a showcase how a risk assessment in the case of contaminated feeding can be performed.     

Persistent Organic Pollutants in gull eggs of two species (Larus michahellis and Larus audouinii) from the Ebro delta Natural Park

The aim of this study was to determine the impact of priority and emerging Persistent Organic Pollutants (POPs) in gull eggs from two species, the scavenger Larus michahellis and the protected species, Larus audouinii. These two species share habitat in the Natural Park of the Ebro delta (Catalonia, Spain). Compounds studied are included or under consideration in the Stockholm Convention and comprise polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), organochlorinated compounds (OCs), perfluorinated compounds (PFCs) and short chain chlorinated paraffins (SCCPs). Four methods based in selective extraction and gas or liquid chromatography coupled to mass spectrometry were used and quality parameters are provided. OC pesticides and marker PCBs were the most abundant chemical families detected in eggs from the two species, followed by PFCs, PBDEs (especially BDE 209) and SCCPs. Dioxin-like PCBs and PCDD/Fs were also detected in all samples. The overall widespread presence of POPs is discussed in terms of feeding habits, bird ecology and anthropogenic pressures in the protected Ebro delta breeding area.     

Climate change impact on countrywide water balance in Bolivia

There is increasing concern about the ongoing reduction in water supplies in the tropical Andes due to climate change effects such as glacier/snow melting resulting from rising air temperatures. In addition, extreme events and population growth are already directly affecting life and water renewability in the country. A countrywide integrated national plan for improving basin-scale water management in Bolivia is needed to assure water availability for agriculture, industry, mining, and human consumption. This study aims to provide a modeling tool to assess Bolivia’s past, current, and future water availability and identify basins at risk of water deficits. The Soil Water Assessment Tool was used to simulate the monthly water balance from 1997 to 2008, as well as the water balance projected to 2050 for the entire country. It considers possible changes in air temperatures and precipitation proposed by 17 Global Circulation Models as well as carbon dioxide projections derived from the Special Report Emission Scenario. Overall, model results were close to satisfactory compared to observations, with some exceptions due to lack of information for expanding the timeline and improving calibration. Based on the calculation of three hydrologic indicators, the study identifies basins that would be the most susceptible to water deficits for a baseline from 1997 to 2008, and in the event of the projected climate change, to 2050.     

Microalgae biosynthesis of silver nanoparticles for application in the control of agricultural pathogens

The occurrence of diseases in cultivars has caused significant losses in global food production. The advancement of nanobiotechnology makes it possible to obtain new products to be used in the control of pathogens in cultivars. Silver nanoparticles can be synthesized by microalgae and are widely known for their antimicrobial activity. In addition, the biomass produced in microalgal culture for the biosynthesis of the nanoparticles also demonstrates antimicrobial properties, as it can increase the antibacterial and antifungal potential of the silver nanoparticles. In this context, this article addresses the use of microalgae to biosynthesize silver nanoparticles simultaneously with biomass production. In addition, we demonstrate the antimicrobial potential of these nanomaterials, as well as of the microalgal biomass produced in biosynthesis, to use in the control of pathogens in agriculture.     

Fluoride Cycling near A Coastal Emission Source

A strategy of research combining intense field monitoring and compartment modeling was used to characterize fluoride cycling in the semi-arid area around a newly installed aluminum factory in southern Argentina. The factory started operations In 1974 and emitted about 500 tons of gaseous fluorides to the atmosphere up to October 1976. Emphasis of research was on sedimentary or detritus cycling; periodically, samples were obtained from plant tissues, soils, sea water, and sea sediments. A compartment model of fluoride circulation at the atmosphere-vegetation interface provides further elements to Interpret the tendencies observed in field data. A fluoride budget up to October 1976 is presented showing the relative importance of environmental compartments monitored, with reference to fluoride accumulation. Plants are transient accumulators of atmospheric fluorides; soils, sea-water, and sea-sediments are sinks of the cycle. The major pathway of fluoride from terrestrial environment to coastal sea water Is along transportation with superficial soil eroded by wind. According to data here presented, it can be concluded that one wind storm can transport enough soluble fluorides to coastal waters to account for the transient differences of concentration observed.