Recreational System Optimization to Reduce Conflict on Public Lands

In response to federal administrative rule, the Tahoe National Forest (TNF), California, USA engaged in trail-route prioritization for motorized recreation (e.g., off-highway-vehicles) and other recreation types. The prioritization was intended to identify routes that were suitable and ill-suited for maintenance in a transportation system. A recreational user survey was conducted online (n?=?813) for user preferences for trail system characteristics, recreational use patterns, and demographics. Motorized trail users and non-motorized users displayed very clear and contrasting preferences for the same system. As has been found by previous investigators, non-motorized users expressed antagonism to motorized use on the same recreational travel system, whereas motorized users either supported multiple-use routes or dismissed non-motorized recreationists' concerns. To help the TNF plan for reduced conflict, a geographic information system (GIS) based modeling approach was used to identify recreational opportunities and potential environmental impacts of all travel routes. This GIS-based approach was based on an expert-derived rule set. The rules addressed particular environmental and recreation concerns in the TNF. Route segments were identified that could be incorporated into minimal-impact networks to support various types of recreation. The combination of potential impacts and user-benefits supported an optimization approach for an appropriate recreational travel network to minimize environmental impacts and user-conflicts in a multi-purpose system.     

Model selection and evaluation for risk assessment of dioxin-contaminated sites

The general European population has a total intake of dioxins and dioxin-like chemicals near the limit recommended by the European Union, making additional exposure above background levels undesirable. For populations living near dioxin-contaminated sites, additional exposure may occur by intake of locally produced food, inhalation of particles, dermal contact with soils, or other exposure pathways. Risk assessment tools are required to estimate risks associated with contaminated sites and to set priorities for site remediation. Here, we review several multimedia models that can be applied as tools to support risk assessment. We then present a strategy to select, apply, evaluate, and adapt a model to address a specific situation. The case study we consider is a risk assessment of generic background dioxin exposure in Sweden, and we compare the predictions with environmental observations and exposure data from Sweden. Arguments are presented for selecting the CalTOX model for this case study. We demonstrate the application, evaluation, and adaptation of the model and discuss the requirements for extending the analysis to conduct risk assessment for subpopulations living near dioxin-contaminated sites.     

Evaluation of non-enteric sources of non-methane volatile organic compound (NMVOC) emissions from dairies

Dairies are believed to be a major source of volatile organic compounds (VOC) in Central California, but few studies have characterized VOC emissions from these facilities. In this work, samples were collected from six sources of VOCs (Silage, Total Mixed Rations, Lagoons, Flushing Lanes, Open Lots and Bedding) at six dairies in Central California during 2006–2007 using emission isolation flux chambers and polished stainless steel canisters. Samples were analyzed by gas chromatography/mass spectrometry and gas chromatography/flame ionization detection. Forty-eight VOCs were identified and quantified in the samples, including alcohols, carbonyls, alkanes and aromatics. Silage and Total Mixed Rations are the dominant sources of VOCs tested, with ethanol as the major VOC present. Emissions from the remaining sources are two to three orders of magnitude smaller, with carbonyls and aromatics as the main components. The data suggest that animal feed rather than animal waste are the main source of non-enteric VOC emissions from dairies.     

Flood vulnerability,risk, and social disadvantage: current and future patterns in the UK

Regional Environmental Change - Present day and future social vulnerability, flood risk, and disadvantage across the UK are explored using the UK Future Flood Explorer. In doing so, new indices of...     

Deconstructing compassionate conservation

Compassionate conservation focuses on 4 tenets: first, do no harm; individuals matter; inclusivity of individual animals; and peaceful coexistence between humans and animals. Recently, compassionate conservation has been promoted as an alternative to conventional conservation philosophy. We believe examples presented by compassionate conservationists are deliberately or arbitrarily chosen to focus on mammals; inherently not compassionate; and offer ineffective conservation solutions. Compassionate conservation arbitrarily focuses on charismatic species, notably large predators and megaherbivores. The philosophy is not compassionate when it leaves invasive predators in the environment to cause harm to vastly more individuals of native species or uses the fear of harm by apex predators to terrorize mesopredators. Hindering the control of exotic species (megafauna, predators) in situ will not improve the conservation condition of the majority of biodiversity. The positions taken by so-called compassionate conservationists on particular species and on conservation actions could be extended to hinder other forms of conservation, including translocations, conservation fencing, and fertility control. Animal welfare is incredibly important to conservation, but ironically compassionate conservation does not offer the best welfare outcomes to animals and is often ineffective in achieving conservation goals. Consequently, compassionate conservation may threaten public and governmental support for conservation because of the limited understanding of conservation problems by the general public.     

A call to action for climate change research on Caribbean dry forests

Regional Environmental Change - Tropical dry forest (TDF) is globally one of the most threatened forest types. In the insular Caribbean, limited land area and high population pressure have resulted...     

Improving collection efficiency through remote monitoring of charity assets

Collection costs associated with servicing a major UK charity’s donation banks and collecting unsold goods from their retail shops can account for up to 20% of the overall income gained. Bank and shop collections are commingled and are typically made on fixed days of the week irrespective of the amounts of materials waiting to be collected. Using collection records from a major UK charity, this paper considers what vehicle routing and scheduling benefits could accrue if bank and shop servicing requirements were monitored, the former using remote sensing technology to allow more proactive collection scheduling. A vehicle routing and scheduling algorithm employing tabu search methods was developed, and suggested time and distance savings of up to 30% over the current fixed schedules when a minimum bank and shop fill level of between 50% and 60% was used as a collection trigger. For the case study investigated, this led to a potential revenue gain of 5% for the charity and estimated CO₂ savings of around 0.5 tonnes per week across the fleet of six heterogeneous vehicles.     

Personal and indoor exposure to PM2.5 and polycyclic aromatic hydrocarbons in the southern highlands of Tanzania: a pilot-scale study

Sediment-dwelling macrofauna, polycyclic aromatic hydrocarbons (PAH), and abiotic parameters were monitored annually in benthic marine sediments from 1989-2007 in Port Valdez, a period of declining routine discharge of treated marine ballast water containing residual PAH from a major crude oil loading facility. The resulting dataset was used to evaluate associations between macrofauna and environmental characteristics including PAH concentrations. The influences of natural abiotic gradients on macrofauna were stronger than associations between macrofauna and sediment PAH. Though overall associations of PAH with macrofaunal community structure were weak, effects were greater for the tube-dwelling polychaete worms Galathowenia oculata and Melinna cristata which responded negatively to low PAH values near sediment quality criteria (threshold effects concentration: TEC and field-based sediment quality criterion: fb-SQG: ～300 ng g(?-1)). Effects of PAH on benthic fauna may be strongest through poor survival of juveniles and failed recruitment over multiple years. Comparison of measured PAH concentrations to the TEC and field-based fb-SQG suggest that the observed levels of change in Port Valdez are minor and the criteria are ecologically appropriate for environmental monitoring. By demonstrating positive responses of sensitive fauna to reduction of PAH concentration, this study contributes to understanding the temporal change, ecological importance, and size of effects expected on benthic fauna in the presence of continuous exposure to low levels of hydrocarbons.