Materials Exchanges: An exploratory US survey

We characterise US materials exchanges by means of an exploratory survey, with 63 respondents classified by materials handled, organisation type and implementation strategy. Few respondents handle hazardous materials; instead, most focus on pre-consumer items such as building materials or post-consumer durable goods such as furniture. Non-profit organisations and state/local government agencies predominate in this niche, which fills a gap between ubiquitous for-profit scrap recyclers and used-merchandise stores. There are three distinct implementation strategies: passive listers of materials; active brokers, who become involved in each transaction; and those who take possession of materials for storage and display in a warehouse. Warehouse operations typically have a local focus and a loyal customer base, whereas passive listing services serve larger areas and are undergoing consolidation. Passive listing services appear to be relatively marginal enterprises, although the adoption of Internet technology is improving their viability.     

Community Sustainability Plans to enable change towards sustainable practice – a Scottish case study

There is a need for a global shift towards a low-carbon society and this requires action at the local level. The aim of the study into sustainable community development is to clarify the role of a community as a whole rather than the role of individuals within that community. Mixed methods of literature review and empirical study have been used to translate the knowledge and experience with urban sustainable development into empirical knowledge of a rural, market town setting. The exemplary case study is the Scottish market town Huntly. The main findings of the study show the need for three ingredients for a Community Sustainability Plan for a town such as Huntly. Community involvement is crucial in developing such plans in a rural setting. Further research in more remote settings, e.g. coastal and island communities, is needed to allow broader conclusions on rural sustainable development.     

Improving Conservation of Florida Manatees (Trichechus manatus latirostris): Conceptualization and Contributions Toward a Regional Warm-Water Network Management Strategy for Sustainable Winter Habitat

We used southwestern Florida as a case study to lay the groundwork for an intended and organized decision-making process for managing warm-water habitat needed by endangered manatees to survive winters in Florida. Scientists and managers have prioritized (a) projecting how the network of warm-water sites will change over the next 50 years as warmed industrial discharges may expire and as flows of natural springs are reduced through redirection of water for human uses, and (b) mitigating such changes to prevent undue consequences to manatees. Given the complexities introduced by manatee ecology; agency organizational structure; shifting public demands; fluctuating resource availability; and managing within interacting cultural, social, political, and environmental contexts, it was clear that a structured decision process was needed. To help promote such a process, we collected information relevant to future decisions including maps of known and suspected warm-water sites and prototyped a characterization of sites and networks. We propose steps that would lead to models that might serve as core tools in manatee/warm-water decision-making, and we summarized topics relevant for informed decision-making (e.g., manatee spatial cognition, risk of cold-stress morbidity and mortality, and human dimensions). A major impetus behind this effort is to ensure proactively that robust modeling tools are available well in advance of the anticipated need for a critical management decision.     

Positive perceptions of green and open space as predictors of neighbourhood quality of life: implications for urban planning across the city region

The provision of green and open space in the face of wider development pressure is a key urban challenge. Despite this, few studies have critically investigated the quality of life implications of such provision. This paper focuses on perceptions of built environment factors and their influence on neighbourhood quality of life. Data are drawn from a household survey questionnaire completed by 483 residents living in three neighbourhoods in Dublin, Ireland – an inner city neighbourhood, a suburb and a peri-urban settlement. Positive perceptions of green and open space were identified as important predictors of high levels of neighbourhood satisfaction, surpassed only by dwelling characteristics. This suggests that development strategies which fail to provide for properly planned green and open spaces may be detrimental to neighbourhood quality of life. Furthermore, the results suggest a need for design solutions which consider neighbourhood typology in achieving improved neighbourhood quality of life.     

Planetary Stewardship in an Urbanizing World: Beyond City Limits

Cities are rapidly increasing in importance as a major factor shaping the Earth system, and therefore, must take corresponding responsibility. With currently over half the world’s population, cities are supported by resources originating from primarily rural regions often located around the world far distant from the urban loci of use. The sustainability of a city can no longer be considered in isolation from the sustainability of human and natural resources it uses from proximal or distant regions, or the combined resource use and impacts of cities globally. The world’s multiple and complex environmental and social challenges require interconnected solutions and coordinated governance approaches to planetary stewardship. We suggest that a key component of planetary stewardship is a global system of cities that develop sustainable processes and policies in concert with its non-urban areas. The potential for cities to cooperate as a system and with rural connectivity could increase their capacity to effect change and foster stewardship at the planetary scale and also increase their resource security.     

Aviation and global climate change in the 21st century

Aviation emissions contribute to the radiative forcing (RF) of climate. Of importance are emissions of carbon dioxide (CO₂), nitrogen oxides (NO_x), aerosols and their precursors (soot and sulphate), and increased cloudiness in the form of persistent linear contrails and induced-cirrus cloudiness. The recent Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) quantified aviation's RF contribution for 2005 based upon 2000 operations data. Aviation has grown strongly over the past years, despite world-changing events in the early 2000s; the average annual passenger traffic growth rate was 5.3% yr^?1 between 2000 and 2007, resulting in an increase of passenger traffic of 38%. Presented here are updated values of aviation RF for 2005 based upon new operations data that show an increase in traffic of 22.5%, fuel use of 8.4% and total aviation RF of 14% (excluding induced-cirrus enhancement) over the period 2000–2005. The lack of physical process models and adequate observational data for aviation-induced cirrus effects limit confidence in quantifying their RF contribution. Total aviation RF (excluding induced cirrus) in 2005 was ～55 mW m^?2 (23–87 mW m^?2, 90% likelihood range), which was 3.5% (range 1.3–10%, 90% likelihood range) of total anthropogenic forcing. Including estimates for aviation-induced cirrus RF increases the total aviation RF in 2005–78 mW m^?2 (38–139 mW m^?2, 90% likelihood range), which represents 4.9% of total anthropogenic forcing (2–14%, 90% likelihood range). Future scenarios of aviation emissions for 2050 that are consistent with IPCC SRES A1 and B2 scenario assumptions have been presented that show an increase of fuel usage by factors of 2.7–3.9 over 2000. Simplified calculations of total aviation RF in 2050 indicate increases by factors of 3.0–4.0 over the 2000 value, representing 4–4.7% of total RF (excluding induced cirrus). An examination of a range of future technological options shows that substantive reductions in aviation fuel usage are possible only with the introduction of radical technologies. Incorporation of aviation into an emissions trading system offers the potential for overall (i.e., beyond the aviation sector) CO₂ emissions reductions. Proposals exist for introduction of such a system at a European level, but no agreement has been reached at a global level.     

Elevated testosterone advances onset of migratory restlessness in a nearctic-neotropical landbird

The primary cue for initiation of spring migratory restlessness (Zugunruhe) in landbird migrants is photoperiod. Gonadal hormones are known to have a role in the regulation of migratory disposition; however, the extent of their effect is not well understood. We examined the impact of exogenous testosterone on the onset of migratory restlessness in gray catbirds (Dumetella carolinensis). Catbirds were stratified by sex and randomly assigned to two rooms; individuals in one room were photoadvanced to initiate migratory restlessness and the other room was maintained on a 12:12 light/dark photoperiod. Each room had three groups (n?=?10/group); males with testosterone implants, males with empty implants, and females. We predicted that in the photoadvanced room males with testosterone implants would initiate migratory activity earlier than empty-implanted males. We found that in the photoadvanced group, testosterone-implanted males initiated migration 2 weeks prior to empty-implanted males, and 3 weeks prior to females. In the non-photoadvanced males, the testosterone-implanted males initiated migration at the same time as the corresponding group in the photoadvanced room, while the empty-implanted males and females did not exhibit Zugunruhe. Our results illustrate that elevated testosterone can advance the onset of Zugunruhe, even in the absence of an extended photoperiod. Additionally, the onset of migratory restlessness observed in the photoadvanced, non-testosterone-implanted males and females further supports the importance of photoperiod as a cue for migratory restlessness. An interesting observation was the intersexual differences in the onset of migratory activity in gray catbirds, a species not previously known to exhibit protandry.     

Ontogeny of early diving and foraging behavior of northern fur seal (Callorhinus ursinus) pups from Bering Island,Russia

The ontogeny of diving and foraging behavior of northern fur seal pups from a stable population on Bering Island, Russia, was recorded with animal-borne instruments during their first few months at sea, a critical period during their first year at sea. Thirty-five pups were instrumented with satellite-linked time-depth recorders and stomach temperature pills. Diving occurred predominantly at night with deeper and longer dives as the pups matured. Mean dive depths were correlated with lunar illumination, whereas mean dive durations were also correlated with time of day and sex. Foraging success did not differ between sexes, and there was no relationship between meal size (as indicated by feeding event duration and minimum stomach temperature) and lunar illumination fraction or maximum foraging depth. Although most pups were able to successfully forage within 3 days of starting their migration, the number of feeding events recorded each day remained low (mean 1.6 events day^?1). There was no indication of an appreciable increase in meal size after the first 2 weeks of the migration despite an increase in dive frequency and depth. The results are consistent with observations that pups do not gain mass during their first year and emphasize the risk of starvation from infrequent foraging in cold water.