Influence of groundwater conditions and co‐contaminants on sorption of perfluoroalkyl compounds on granular activated carbon

Per and polyfluoroalkyl substances (PFAS) are emerging and persistent organic pollutants that have been detected in many environmental media, humans, and wildlife. A common method to effectively remove PFAS from water is adsorption by activated carbon. Preliminary sorption experiments were conducted using five characterized Calgon Corporation coal‐based granular activated carbon (GAC; F100, F200, F816, F300, and F400), one coconut‐based GAC (CBC‐OLC 12 × 30), and one Jacobi Corporation coal‐based GAC (Omni‐G 12 × 40). Sorption of four representative PFAS onto each GAC was measured to select the most favorable carbon sources. F400 and CBC were chosen based on their performance in preliminary PFAS sorption experiments and contrasting properties. Freundlich and Langmuir isotherm models were developed for perfluorooctanoic acid (PFOA) and perfluorooctanoic sulfonate (PFOS) at an initial concentration of 1 mg/L. Sorption capacities were determined for PFOA and PFOS individually and in the mixture. Individual compounds showed higher sorption than when present in the mixture for both PFOA and PFOS. PFOS showed higher sorption than PFOA both individually and in the mixture and F400 showed higher sorption capacity than CBC. The presence of co‐contaminants (kerosene, trichloroethylene, and ethanol), and variations in groundwater conditions (pH, presence of anions, naturally occurring organic matter, and iron oxides) demonstrated limited impact on the sorption of PFAS onto GAC under the experimental conditions tested.     

Ecological Conservation Through Aesthetic Landscape Planning: A Case Study of the Lower Wisconsin State Riverway

A consequence of expanding residential development into rural areas is the potential alteration of ecological communities. Certain novel land-use policies seek practical solutions by accommodating social needs for housing while conserving biodiversity. This study investigates whether regulations designed to protect the aesthetic characteristics of a river corridor simultaneously mitigate negative effects of development on avian biodiversity, despite the absence of explicit conservation objectives. Using housing data from the US Census (1990 and 2000) and the Audubon Christmas Bird Count (1987–2000), we examined changes in housing density, avian communities, and the relationship between these two variables in a location that has adopted aesthetic landscape planning, the Lower Wisconsin State Riverway. We found that overall species diversity increased in the Riverway, but remained constant in reference areas, although the relative increase in housing density in the two areas did not differ. We also found that omnivore populations decreased in the Riverway and increased in reference sites. On the whole, our study provides preliminary evidence that aesthetic landscape planning, such as employed in the Lower Wisconsin State Riverway, might constitute a politically viable approach to conserve ecological resources.     

Trends in Global Protected Area Governance,1992–2002

Governance refers to the interactions among structures, processes, and traditions that determine direction, how power is exercised, and how the views of citizens or stakeholders are incorporated into decision-making. Governance is now recognized as a critical aspect of effective conservation and is a prominent part of the Convention on Biological Diversity’s work program on protected areas. This study reports on a global survey to assess changes in governance of protected area systems between 1992 and 2002 based on responses from 41 countries. Results indicate that substantial changes have taken place with overall trends towards increased participation of more stakeholders, greater use of formal accountability mechanisms, and a wider range of participatory techniques. Many of these changes are supported by legislative and policy requirements and 75% of respondents reported changes in legislation over the past decade. Protected areas are becoming more influenced by global forces. A majority of respondents reported increased involvement of the private sector. Funding is coming from a broader range of sources, with a smaller proportion of income coming from government sources in 2002. Absolute funding amounts have increased, but almost two-thirds report that budgets fall short of requirements. Almost 90% of respondents felt that protected area governance had improved over the last decade; 67% felt that this had also led to improved management effectiveness. Respondents felt that secure funding, capacity building, and increased community involvement were the main governance needs for the future.     

Leaching and sorption of neonicotinoid insecticides and fungicides from seed coatings

Seed coatings are a treatment used on a variety of crops to improve production and offer protection against pests and fungal outbreaks. The leaching of the active ingredients associated with the seed coatings and the sorption to soil was evaluated under laboratory conditions using commercially available corn and soybean seeds to study the fate and transport of these pesticides under controlled conditions. The active ingredients (AI) included one neonicotinoid insecticide (thiamethoxam) and five fungicides (azoxystrobin, fludioxonil, metalaxyl, sedaxane thiabendazole). An aqueous leaching experiment was conducted with treated corn and soybean seeds. Leaching potential was a function of solubility and seed type. The leaching of fludioxonil, was dependent on seed type with a shorter time to equilibrium on the corn compared to the soybean seeds. Sorption experiments with the treated seeds and a solution of the AIs were conducted using three different soil types. Sorption behavior was a function of soil organic matter as well as seed type. For most AIs, a negative relationship was observed between the aqueous concentration and the log K_oc. Sorption to all soils tested was limited for the hydrophilic pesticides thiamethoxam and metalaxyl. However, partitioning for the more hydrophobic fungicides was dependent on both seed type and soil properties. The mobility of fludioxonil in the sorption experiment varied by seed type indicating that the adjuvants associated with the seed coating could potentially play a role in the environmental fate of fludioxonil. This is the first study to assess, under laboratory conditions, the fate of pesticides associated with seed coatings using commercially available treated seeds. This information can be used to understand how alterations in agricultural practices (e.g., increasing use of seed treatments) can impact the exposure (concentration and duration) and potential effects of these chemicals to aquatic and terrestrial organisms.     

Resilience thinking applied to fisheries management: perspectives for the mullet fishery in Southern-Southeastern Brazil

The mullet fishery system encompasses a complex arrange of ecological and socioeconomic factors interacting in multiple scales on the Southern-Southeastern Brazilian coast. Similarly, to other fisheries in developing countries, overfishing and poor governance have been threatening the resilience of the mullet fishery. In this paper, we explore aspects related to fisheries management from the perspective of the concept of resilience. The industrial and artisanal fishery sectors represent the different stakeholders. The main issues of concern are related to failures in the fisheries management to properly address equity in resource access and resource use sustainability among stakeholders. Asymmetry in technology and political and economic power affect food security and income generation especially for subsistence and small-scale fishing. Despite changes in rules-in-use, overfishing and conflicts between resource users are still relevant. Fishery dynamics and resource availability are greatly affected locally by forces such as pollution, urbanization, non-selective fishing, and regionally, by the El Niño Southern Oscillation (ENSO), and industrial (purse-seine) fishery. Considering the influence of ENSO on this fishery, a time span of at least 7 years to investigate this system could provide better answers to improve the management. Effective resilient fisheries should rely on three aspects. First, there should be a flexible fish allocation system based on ecosystem variability. Secondly, fish allocation should prioritize food security and poverty alleviation. Thirdly, a monitoring system should be implemented that takes into consideration ecosystem, fisheries and human dimensions to support a flexible and adaptive fisheries management, with resilient fisheries as an ultimate goal.     

The effect of summer drought on the predictability of local extinctions in a butterfly metapopulation

The ecological impacts of extreme climatic events on population dynamics and community composition are profound and predominantly negative. Using extensive data of an ecological model system, we tested whether predictions from ecological models remain robust when environmental conditions are outside the bounds of observation. We observed a 10-fold demographic decline of the Glanville fritillary butterfly (Melitaea cinxia) metapopulation on the Åland islands, Finland in the summer of 2018 and used climatic and satellite data to demonstrate that this year was an anomaly with low climatic water balance values and low vegetation productivity indices across Åland. Population growth rates were strongly associated with spatiotemporal variation in climatic water balance. Covariates shown previously to affect the extinction probability of local populations in this metapopulation were less informative when populations were exposed to severe drought during the summer months. Our results highlight the unpredictable responses of natural populations to extreme climatic events.     

Concentration of tetrachloroethylene in indoor air at a former dry cleaner facility as a function of subsurface contamination: a case study

A field study was performed to evaluate indoor air concentrations and vapor intrusion (VI) of tetrachloroethylene (PCE) and other chlorinated solvents at a commercial retail site in Dallas, TX. The building is approximately 40 yr old and once housed a dry cleaning operation. Results from an initial site characterization were used to select sampling locations for the VI study. The general approach for evaluating VI was to collect time-integrated canister samples for off-site U.S. Environmental Protection Agency Method TO-15 analyses. PCE and other chlorinated solvents were measured in shallow soil gas, subslab soil-gas, indoor air, and ambient air. The subslab soil gas exhibited relatively high values: PCE < or =2,600,000 parts per billion by volume (ppbv) and trichloroethylene < or =170 ppbv. The attenuation factor, the ratio of indoor air and subslab soil-gas concentrations, was unusually low: approximately 5 x 10(-6) based on the maximum subslab soil-gas concentration of PCE and 1.4 x 10(-5) based on average values.