Assessment of Several Test Methods for the Determination of the Anaerobic Biodegradability of Polymers

Anaerobic degradation of eight commercially available biodegradable polymers was compared in two anaerobic tests using digestion sludge, according to ISO 11734 and ASTM D.5210-91. Cotton, polyhydroxybutyrate/hydroxyvalerate copolymer (PHB/PHV), starch blend, thermoplastic cellulose acetate, and cellulose acetate fibers proved to be anaerobically degradable, but only a low extent of degradation was found for polylactide, polyvinylalcohol, and polycaprolactone. Both test methods gave the same overall results, but with the ISO medium, longer lag phases and greater ranges of variation in the results were observed. These effects are presumably due to low concentrations of carbon dioxide in the ISO medium. Carbon dioxide has been demonstrated to be essential for the growth of various anaerobic bacteria, notably homoacetogenic and methanogenic bacteria.     

Modeling instability development in layered systems

This study investigates patterns of finger development and propagation in layered porous media. Fingers are created with interfacial perturbations, formed by adding a thin zone of regularly varying hydraulic conductivity along the layer. Simulation results agree qualitatively with those observed in two-dimensional laboratory experiments. In all cases, the formation of instabilities requires seeding of perturbations, even if the system is unstably stratified. A series of simulations show how the shapes of the instabilities differ according to where along the unstable interface the instabilities form and the layer in which they develop. Pathline analyses indicate how the patterns of flow in the domain can be exceedingly complex. Concentration distributions are influenced by movements of water between layers and the formation of a large convection cell in the lowermost layer. These numerical investigations reinforce inferences from the experimental studies that classical stability theory is less useful in determining whether instabilities will form and what their shape will be. Even with the relatively simple layering, patterns of flow and resulting concentrations are complex.     

Incorporation of Spatial and Economic Analyses of Human‐Use Data in the Design of Marine Protected Areas

Abstract: Social, economic, and ecological criteria contribute to the successful design, implementation, and management of marine protected areas (MPAs). In the context of California's Marine Life Protection Act Initiative, we developed a set of methods for collecting, compiling, and analyzing data about the spatial extent and relative economic importance of commercial and recreational fishing. We interviewed 174 commercial fishers who represented the major fisheries in the initiative's north‐central coast region, which extends from Point Arena south to Pigeon Point. These fishers provided data that we used to map the extent of each of the fishing grounds, to weight the relative importance of areas within the grounds, to characterize the operating costs of each fishery, and to analyze the potential economic losses associated with proposed marine protected areas. A regional stakeholder group used the maps and impact analyses in conjunction with other data sets to iteratively identify economic and ecological trade‐offs in designations of different areas as MPAs at regional, port, and fishery extents. Their final proposed MPA network designated 20% of state waters as MPAs. Potential net economic loss ranged from 1.7% to 14.2% in the first round of network design and totaled 6.3% in the final round of design. This process is a case study in the application of spatial analysis to validate and integrate local stakeholder knowledge in marine planning.     

Identifying Reefs of Hope and Hopeful Actions: Contextualizing Environmental, Ecological, and Social Parameters to Respond Effectively to Climate Change

Abstract:  Priorities for conservation, management, and associated activities will differ based on the interplay between nearness of ecosystems to full recovery from a disturbance (pristineness), susceptibility to climate change (environmental susceptibility [ES]), and capacity of human communities to cope with and adapt to change (social adaptive capacity [AC]). We studied 24 human communities and adjacent coral reef ecosystems in 5 countries of the southwestern Indian Ocean. We used ecological measures of abundance and diversity of fishes and corals, estimated reef pristineness, and conducted socioeconomic household surveys to determine the AC of communities adjacent to selected coral reefs. We also used Web-based oceanographic and coral mortality data to predict each site's ES to climate warming. Coral reefs of Mauritius and eastern Madagascar had low ES and consequently were not predicted to be affected strongly by warm water, although these sites were differentiated by the AC of the human community. The higher AC in Mauritius may increase the chances for successful self-initiated recovery and protective management of reefs of this island. In contrast, Madagascar may require donor support to build AC as a prerequisite to preservation efforts. The Seychelles and Kenya had high ES, but their levels of AC and disturbance differed. The high AC in the Seychelles could be used to develop alternatives to dependence on coral reef resources and reduce the effects of climate change. Pristineness weighted toward measures of fish recovery was greatest for Kenya's marine protected areas; however, most protected areas in the region were far from pristine. Conservation priorities and actions with realistic chances for success require knowledge of where socioecological systems lie among the 3 axes of environment, ecology, and society.     

Decomposition of Al13 promoted by salicylic acid under acidic condition: Mechanism study by differential mass spectrometry method and DFT calculation

Decomposition of the polycation Al₁₃O₄(OH)₂₄(H₂O)₁₂⁷⁺ (Al₁₃) promoted by ligand is a vital subject to advance our understanding of natural and artificial occurrence and evolution of aluminum ions, especially in the case of acidic condition that dissolved Al³⁺ species can be released from the Al-bearing substances. However, the microscopic pathway of synchronous proton-promoted and ligand-promoted decomposition process for Al₁₃ is still in the status of ambiguity. Herein, we applied differential mass spectrometry method and DFT calculation to study the initial detailed process of Al₁₃ decomposition under the presence of proton and salicylic acid (H₂Sal). Mass results showed that the mononuclear Al³⁺-H₂Sal complexes dominated the resulting Al species, whereas the monodentate complex Al₁₃HSal⁶⁺ was not observed in the spectra. The difference of decomposition levels between the ligand/Al ratio 0.2 and 0.5 cases revealed that proton and ligand performed synergistic effect in initial Al₁₃ decomposition process, and the proton transfer determined the ring closure efficiency. The ring closure reaction is the prerequisite for the collapse of Al₁₃ structure and detachment of the mononuclear complex. DFT calculations reveal that hydrogen bond plays an important role in inducing the formation of chelated complex accompanying proton transfer. Attachment of protons at the bridging OH⁻ can elongate and weaken the critical bond between targeted Al³⁺ and µ₄-O^2- resulting from delocalization of electron pairs in the oxygen atom. These results demonstrate the detailed mechanism of Al₁₃ composition promoted by ligand and proton, and provide significant understanding for further application and control of Al₁₃.     

The social side of spatial decision support systems: Investigating knowledge integration and learning

Spatial decision support systems (SDSS) represent a step forward in efforts to account for the spatial dimension in environmental decision-making. The aim of SDSS is to help policymakers and practitioners access, interpret and understand information from data, analyses and models, and guide them in identifying possible actions during a decision-making process. Researchers, however, report difficulties in up-take of SDSS by the intended users. Some suggest that this field would benefit from investigation of the social aspects involved in SDSS design, development, testing and use. Borrowing insights from the literature on science-policy interactions, we explore two key social processes: knowledge integration and learning. Using a sample of 36 scientific papers concerning SDSS in relation to environmental issues, we surveyed whether and how the selected papers reported on knowledge integration and learning. We found that while many of the papers mentioned communication and collaboration with prospective user groups or stakeholders, this was seldom underpinned by a coherent methodology for enabling knowledge integration and learning to surface. This appears to have hindered SDSS development and later adoption by intended users.     

Narratives Can Motivate Environmental Action: The Whiskey Creek Ocean Acidification Story

Even when environmental data quantify the risks and benefits of delayed responses to rapid anthropogenic change, institutions rarely respond promptly. We propose that narratives complementing environmental datasets can motivate responsive environmental policy. To explore this idea, we relate a case study in which a narrative of economic loss due to regionally rapid ocean acidification—an anthropogenic change—helped connect knowledge with action. We pose three hypotheses to explain why narratives might be particularly effective in linking science to environmental policy, drawing from the literature of economics, environmental policy, and cognitive psychology. It seems that yet-untold narratives may hold similar potential for strengthening the feedback between environmental data and policy and motivating regional responses to other environmental problems.     

Insights into community vulnerability and resilience following natural disasters: perspectives with food retailers in Northern NSW,Australia

The resilience of Australia's food-supply chain following natural disasters has been brought into question, following the significant flooding and cyclone events of 2010/2011. How this manifests at the community level, in both rural and urban locations, has been examined through the lens of large and small food retailers in northern NSW. These interviews reveal the fragility of both the long and short supply chain where transport systems are compromised. Self-imposed standards severely restricted the ability of supermarkets to acquire fresh food, in the face of transport disruptions. Similarly, the precarious position of rural food retailers, exposed to continual fuel and electricity price increases, is compounded by the impact of extreme weather events. The insights captured through this study suggest interception points, or policy entry points, to address the resilience of the food-supply chain.     

Boater Perceptions of Environmental Issues Affecting Lakes in Northern Wisconsin

Understanding public perceptions of the importance of environmental issues is crucial for gauging support for management activities. I present a novel methodological approach to assess the importance boaters placed on 16 water issues in a lake‐rich region of northern Wisconsin. A latent class maximum difference conjoint model was used to examine the relationships between environmental concern and engagement with lake resources. Boaters were grouped to maximize observed heterogeneity in prioritizing issues of concern. Socio‐demographic characteristics, recreation specialization, place attachment, and attitudes concerning aquatic stewardship and invasive species management were then used to predict class membership. This modeling approach identified five groups whose perceptions of issues pertaining to lakes are influenced by their interactions with the lake environment. While anglers were most concerned about fishing quality, sightseers identified lakeshore development and loss of natural habitat. Groups also differed in their socio‐demographic and attitudinal characteristics. The priorities of each group were substantially different from those of the overall sample. Accounting for differences in stakeholders' environmental concerns may improve public involvement in water management initiatives by allowing managers to identify common concerns and prioritize important issues among multiple groups.