The effect of a woodstove changeout on ambient levels of PM2.5 and chemical tracers for woodsmoke in Libby,Montana

Residential woodstoves are the single largest source of PM_2.5 in Libby, MT, resulting in the community being designated as a nonattainment area for PM_2.5. Beginning in 2005, a community-wide woodstove changeout program was implemented that replaced nearly 1200 old stoves with EPA-certified units. In an effort to track the reduction of woodsmoke particles throughout the program, ambient PM_2.5 samples were collected before, during, and after the changeout. These samples were analyzed for seven selected woodsmoke tracers, including vanillin, acetovanillone, guaiacol, 4-ethylguaiacol (methoxyphenols), levoglucosan (sugar anhydride), abietic acid, and dehydroabietic acid (resin acids). Results of the changeout showed that PM_2.5 levels decreased by 20% during the changeout period, while levels of the seven chosen tracer compounds gave variable responses. Levoglucosan levels decreased by 50% while both resin acids increased after the changeout, suggesting a change in the chemistry of the particles. No trend was observed in the levels of methoxyphenols as a group over the changeout period. The results suggest that the concentrations of woodsmoke related PM_2.5 in the Libby airshed have decreased; however, the chemistry of the emitted particles also changed when old woodstoves were replaced with new EPA-certified stoves.     

生态旅游与可持续发展

国际生态旅游学会已经采取了一套标准化措施进行生态旅游指导方针的开发 . 本文介绍了生 态旅游标准的基本概念 ; 生态旅游市场定位之演变 ; 与生态旅游相关的官方政策 ; 以及为当 地居民增加效益的途径 . 总之 , 对旅游产业的可持续性进行世界级定位刚刚开始 , 确保生态 旅游的国际合作正处于初创阶段 .     

Settlement of larval blacklip abalone, Haliotis rubra, in response to green and red macroalgae

Surfaces from the habitat of adult Haliotis rubra were tested as inducers of larval settlement to determine the cues that larvae may respond to in the field. Settlement was high on the green algal species Ulva australis and Ulva compressa (Chlorophyta), the articulated coralline algae Amphiroa anceps and Corallina officinalis, and encrusting coralline algae (Rhodophyta). Biofilmed abiotic surfaces such as rocks, sand and shells did not induce settlement. Ulvella lens was also included as a control. Treatment of U. australis, A. anceps and C. officinalis with antibiotics to reduce bacterial films on the surface did not reduce the settlement response of H. rubra larvae. Similarly, treatment of these species and encrusting coralline algae with germanium dioxide to reduce diatom growth did not significantly reduce larval settlement. These results suggest that macroalgae, particularly green algal species, may play an important role in the recruitment of H. rubra larvae in the field and can be used to induce larval settlement in hatchery culture.     

Atmospheric nitrogen inputs to the Delaware Inland Bays: the role of ammonia

A previous assessment of nitrogen loading to the Delaware Inland Bays indicates that atmospheric deposition provides 15-25% of the total, annual N input to these estuaries. A large and increasing fraction of the atmospheric wet flux is NH(4)(+), which for most aquatic organisms represents the most readily assimilated form of this nutrient. Particularly noteworthy is a 60% increase in the precipitation NH(4)(+) concentration at Lewes, DE over the past 20 years, which parallels the increase in poultry production on the Delmarva Peninsula over this period (currently standing at nearly 585 million birds annually). To further examine the relationship between local NH(3) emissions and deposition, biweekly-integrated gaseous NH(3) concentrations were determined using Ogawa passive samplers deployed at 13 sampling sites throughout the Inland Bays watershed over a one-year period. Annual mean concentrations at the 13 sites ranged from <0.5 microg NH(3)m(-3) to >6 microg NH(3)m(-3), with a mean of 1.6+/-1.0 microg NH(3)m(-3). At most sites, highest NH(3) concentrations were evident during spring and summer, when fertilizer application and poultry house ventilation rates are greatest, and seasonally elevated temperatures induce increased rates of microbial activity and volatilization from soils and animal wastes. The observed north-to-south concentration gradient across the watershed is consistent with the spatial distribution of poultry houses, as revealed by a GIS analysis of aerial photographs. Based on the average measured NH(3) concentration and published NH(3) deposition rates to water surfaces (5-8 mm s(-1)), the direct atmospheric deposition of gaseous NH(3) to the Inland Bays is 3.0-4.8 kg ha(-1)yr(-1). This input, not accounted for in previous assessments of atmospheric loading to the Inland Bays, would effectively double the estimated direct dry deposition rate, and is on par with the NO(3)(-) and NH(4)(+) wet fluxes. A second component of this study examined spatial differences in NO(3)(-) and NH(4)(+) wet deposition within the Inland Bays watershed. In a pilot study, precipitation composition at the Lewes NADP-AIRMoN site (DE 02) was compared with that at a satellite site established at Riverdale on the Indian River Estuary, approximately 21 km southwest. While the volume-weighted mean precipitation NO(3)(-) concentrations did not differ significantly between sites, the NH(4)(+) concentration observed at Riverdale (26.3 micromoles L(-1)) was 73% greater than at Lewes (15.2 micromoles L(-1)). More recently, a NADP site was established at Trap Pond, DE (DE 99), which was intentionally located within the region of intense poultry production. A comparison of the initial two years (6/2001-5/2003) of precipitation chemistry data from Trap Pond with other nearby NADP-AIRMoN sites (Lewes and Smith Island) reveals fairly homogeneous NO(3)(-) wet deposition, but significant spatial differences ( approximately 60%) in the NH(4)(+) wet flux. Overall, these results suggest that local emissions and below-cloud scavenging provide a significant contribution to regional atmospheric N deposition.     

Flow regime affects building behaviour and nest structure in sticklebacks

Animals usually build nests to provide protection, for themselves or their offspring, from adverse environmental conditions. However, different nest structures may be better at providing protection in different environments. The ability to adjust building behaviour and design of nests in response to variation in environmental conditions is therefore likely to be important in determining individual fitness. Here, we look at how the nests of three-spined stickleback (Gasterosteus aculeatus) males differ between still and flowing water conditions. Within flowing water treatments, we find that males select nesting sites with lower than average flow. We also find that nests built in flowing water are smaller and more streamlined than those built in still water. Nests built in flowing water contain more spiggin—an endogenous glycoprotein secreted by nesting males—per gramme of nest material than still water nests, though the absolute spiggin content of nests did not vary with flow regime. These results suggest that male sticklebacks may adjust nest-site selection and nest structure to suit environmental conditions in which they are building. Because flow regime is a factor that is often altered by anthropogenic activities, such as impoundment, channelization and abstraction, this study may also have implications for the conservation of freshwater fish populations.     

Emotion as a source of moral understanding in conservation

Recent debates around the meaning and implications of compassionate conservation suggest that some conservationists consider emotion a false and misleading basis for moral judgment and decision making. We trace these beliefs to a long-standing, gendered sociocultural convention and argue that the disparagement of emotion as a source of moral understanding is both empirically and morally problematic. According to the current scientific and philosophical understanding, reason and emotion are better understood as partners, rather than opposites. Nonetheless, the two have historically been seen as separate, with reason elevated in association with masculinity and emotion (especially nurturing emotion) dismissed or delegitimated in association with femininity. These associations can be situated in a broader, dualistic, and hierarchical logic used to maintain power for a dominant male (White, able-bodied, upper class, heterosexual) human class. We argue that emotion should be affirmed by conservationists for the novel and essential insights it contributes to conservation ethics. We consider the specific example of compassion and characterize it as an emotional experience of interdependence and shared vulnerability. This experience highlights conservationists’ responsibilities to individual beings, enhancing established and widely accepted beliefs that conservationists have a duty to protect populations, species, and ecosystems (or biodiversity). We argue compassion, thus understood, should be embraced as a core virtue of conservation.     

Possible maternal offloading of metals in the plasma,uterine and capsule fluid of pregnant ragged-tooth sharks (Carcharias taurus) on the east coast of South Africa

Environmental Science and Pollution Research - We studied the possible metal offloading onto the progeny of three pregnant female ragged-tooth sharks (Carcharias taurus) (C. taurus). The presences...     

Farmers’ market governance and its role on consumer motives and outcomes

Local food systems and farmers' markets across the USA have experienced unprecedented growth and development in the past 20 years. While scholarship has examined participant demographics and motives for engaging in farmers' markets, few studies have considered the coupled nature of those attending the markets with institutional governance systems used for market coordination. This study examined participation in farmers' markets under the framework of high and low market governance systems, specifically considering the demographics, values for local foods, motives for attending farmers' markets, and outcomes of the experience based on the dichotomous governance classification. Governance was characterized using four attributes: market rules or policies, paid employee(s), a rule governing geography of food origin, and affiliation with an organisation or agency. Our results suggest that market governance may impact (1) which consumers attend the market, (2) motives among those who attend the market, and (3) satisfaction outcome levels among market participants. By better understanding how the emerging governance system impacts who ultimately attends the market (and the outcomes of the experience), agencies coordinating farmers' markets and market managers can ultimately improve the market's reach and experience with greater intentionality.