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Christine S. Olsen Danielle K. Mazzotta Eric Toman A. Paige Fischer 《Environmental management》2014,54(3):571-582
Wildland fire and associated management efforts are dominant topics in natural resource fields. Smoke from fires can be a nuisance and pose serious health risks and aggravate pre-existing health conditions. When it results in reduced visibility near roadways, smoke can also pose hazardous driving conditions and reduce the scenic value of vistas. Communicating about smoke, whether in the preparation phases before a planned burn or during a wildfire event, can enable those at risk to make informed decisions to minimize their exposure to smoke or choose alternate activities that mitigate smoke completely. To date, very little research has been completed on the social aspects of smoke, such as communication or public perceptions. Here, we present findings from an exploratory study that examined challenges and opportunities related to communication (within agencies or to the public) for management of smoke from wildland fires. Interviews were conducted in California, Oregon, Montana, and South Carolina among a purposive sample of individuals, who are involved in fire or smoke management. Findings indicate that smoke poses several challenges to management agencies. Findings also provide insight into potential strategies to address such challenges by improving communication in both inter- and intra-agency situations as well as with members of the public. In particular, prioritizing fire and smoke-related communication within agencies, allocating agency resources specifically for training in communication and outreach endeavors, taking advantage of existing resources including informal social networks among the public, and building long-term relationships both between agencies and with the public were viewed as effective. 相似文献
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Liz Dent Danielle Vick Kyle Abraham Stephen Schoenholtz Sherri Johnson 《Journal of the American Water Resources Association》2008,44(4):803-813
Abstract: Cool summertime stream temperature is an important component of high quality aquatic habitat in Oregon coastal streams. Within the Oregon Coast Range, small headwater streams make up a majority of the stream network; yet, little information is available on temperature patterns and the longitudinal variability for these streams. In this paper we describe preharvest spatial and temporal patterns in summer stream temperature for small streams of the Oregon Coast Range in forests managed for timber production. We also explore relationships between stream and riparian attributes and observed stream temperature conditions and patterns. Summer stream temperature, channel, and riparian data were collected on 36 headwater streams in 2002, 2003, and 2004. Mean stream temperatures were consistent among summers and generally warmed in a downstream direction. However, longitudinal trends in maximum temperatures were more variable. At the reach scale of 0.5‐1.7 km, maximum temperatures increased in 17 streams, decreased in seven streams and did not change in three reaches. At the subreach scale (0.1‐1.5 km), maximum temperatures increased in 28 subreaches, decreased in 14, and did not change in 12 subreaches. Models of increasing temperature in a downstream direction may oversimplify fine‐scale patterns in small streams. Stream and riparian attributes that correlated with observed temperature patterns included cover, channel substrate, channel gradient, instream wood jam volume, riparian stand density, and geology type. Longitudinal patterns of stream temperature are an important consideration for background characterization of water quality. Studies attempting to evaluate stream temperature response to timber harvest or other modifications should quantify variability in longitudinal patterns of stream temperature prior to logging. 相似文献
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Digestive enzyme profiles of puerulus, post-puerulus, juvenile and adult stages of the spiny lobster Jasus edwardsii Hutton were determined in order to identify ontogenetic changes in digestive capabilities and assess capacity to use dietary components and to exploit diets to meet nutritional requirements. Juvenile and adult lobsters exhibited a diverse range of enzymes, suggesting they can exploit varied diets. Proteolytic activity of trypsin, chymotrypsin and carboxypeptidase A (1.86–3.70 U mg–1 digestive gland protein) was significantly higher than carbohydrase activity of amylase, -glucosidase, cellulase and chitinase (0.0014–0.38 U mg–1 digestive gland protein), thus showing that dietary protein was more important than carbohydrate and that the lobster is carnivorous. These conclusions are consistent with other studies that found spiny lobsters to feed predominantly on crabs, bivalves, ophiuroids and sponges. Lipase activity (0.371 U mg–1 digestive gland protein) was also relatively high, thus showing the importance of dietary lipid. Total activities (units per digestive gland) of every enzyme assayed increased significantly with lobster carapace length. There were few significant ontogenetic trends in specific enzyme activity (U mg–1 digestive gland protein). Amylase and laminarinase specific activity was significantly higher in small lobsters than large lobsters (regression analyses, respectively, F(1,23)=9.84, P=0.005; F(1,11)=19.65, P=0.001), suggesting that carbohydrates including laminarin are more important in the diet of small juveniles. Trypsin, amylase and lipase activities were detected in all non-feeding puerulus stages, suggesting that feeding is not a cue for digestive enzyme production in J. edwardsii. Significant variations in total and specific activities of amylase (F(1,3)=14.2, P=0.00; F(1,3)=14.2, P=0.00) and trypsin (F(1,3)=8.8, P=0.00; F(1,3)=21.41, P=0.00) and a declining trend in lipase total activity between non-feeding puerulus stages suggests that they may be hydrolysing endogenous energy reserves to sustain their onshore swimming activity prior to settlement. Profiles suggest carbohydrate and lipid are utilised first, followed by protein. Consistently high levels of lipase in all puerulus stages (0.24–0.7 U digestive gland–1; P>0.05) confirm the importance of lipid as a major energy substrate.Communicated by G.F. Humphrey, Sydney 相似文献
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Learning,retention and coding of nest-associated visual cues by the Australian desert ant, <Emphasis Type="Italic">Melophorus bagoti</Emphasis> 总被引:3,自引:0,他引:3
Ajay Narendra Aung Si Danielle Sulikowski Ken Cheng 《Behavioral ecology and sociobiology》2007,61(10):1543-1553
A variety of social insects use visual cues for homing. In this study, we examine the possible factors affecting the learning
and retention of nest-associated visual cues by the Australian desert ant Melophorus bagoti and the manner in which such cues are encoded by foraging ants. We placed four prominent cylindrical landmarks around a nest
and trained foragers from that nest to a food source. Ants were tested with the landmark array in a distant testing field
after (1) a known number of exposures to the landmarks (1, 3, 7 or 15 trials, spread over a period of 1 day, 2 days or ≥3 days)
and (2) after a known period of delay (0, 24, 48, 96 or 192 h). The results show that a combination of an increase in training
trials and an increase in number of training days affected the acquisition of landmark memory. Moreover, once the landmarks
were learnt, they became a part of long-term memory and lasted throughout the ants’ foraging lifetime. To examine visual cue
encoding behaviour, ants trained under similar conditions for 4 days were tested with (1) an identical landmark array, (2)
landmarks of the same size used in training, but placed at twice the distance from each other, and (3) landmarks whose dimensions
were doubled and placed at twice the distance from each other. In conditions (1) and (3), the ants searched extensively at
the centre of the four landmarks, suggesting that, similar to the Saharan ant (genus Cataglyphis) and the honeybee, M. bagoti too uses a snapshot to match the view of the landmarks around the nest. But contrary to the snapshot model, in condition
(2), the ants did not search extensively at the centre of the landmarks, but searched primarily 0.5 m from the landmark, the
distance from each landmark to the nest during training. We discuss how various search models fare in accounting for these
findings. 相似文献
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Burke PM Hill S Iricanin N Douglas C Essex P Tharin D 《Environmental monitoring and assessment》2002,80(2):149-173
Automatic samplers are a common method of data collection for numerous monitoring projects in the South Florida region and elsewhere. Although total phosphorus (TP) is the primary parameter of interest within this region, nitrogen species such as ammonia nitrogen (NH4-N), nitrate+nitrite nitrogen (NOx-N), and total kjeldahl nitrogen (TKN) are also collected and analyzed. Federal and state quality assurance guidelines require nutrient samples to be preserved by acidification with H2SO4 to a pH < 2 and stored immediately at 4 °C. However, the remoteness of manysampling locations in South Florida makes it difficult to supplyelectricity for the refrigeration of samples collected by autosamplers. In addition, the use of propane-powered refrigerated autosamplers is a costly and ineffective solution in the South Florida climate. Consequently, while samples collected at these remote locations are routinely pre-preservedwith acid, they are not cooled to 4 °C for a period fromone to seven days. This study evaluated if a statistically significant difference ( = 0.05) existed between concentrations of nitrogen species from a common source samplethat was either: processed immediately; refrigerated to 4 °C for seven days; or not refrigerated for seven days.In all cases, the collected sample was pre-preserved by adding 1 mL of 50% H2SO4 to each 1 L discrete sample container before each 7 day testing period. Differences in concentrations of the calculated parameter total nitrogen (TN)were also investigated.Analyses using the Wilcoxon Signed-Rank Test showed no significant differences among the three treatment groups for NOx-N, TKN, TN and TP. Significant differences were observedwhen the NH4-N samples that were processed immediately werepaired with NH4-N samples that were left unrefrigerated or refrigerated for seven days. Information from this study can be used by researchers and managers in evaluating the usefulness of nutrient water quality data that is collected when sample refrigeration is not available. 相似文献
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Community motivations to engage in conservation behavior to conserve the Sumatran orangutan 下载免费PDF全文
Danielle Nilsson Galina Gramotnev Greg Baxter James R.A. Butler Serge A. Wich Clive A. McAlpine 《Conservation biology》2016,30(4):816-826
Community‐based conservation programs in developing countries are often based on the assumption that heteronomous motivation (e.g., extrinsic incentives such as economic rewards and pressure or coercion to act) will incite local communities to adopt conservation behaviors. However, this may not be as effective or sustainable as autonomous motivations (e.g., an intrinsic desire to act due to inherent enjoyment or self‐identification with a behavior and through freedom of choice). We analyzed the comparative effectiveness of heteronomous versus autonomous approaches to community‐based conservation programs through a case study of Sumatran orangutan (Pongo abelii) conservation in 3 villages in Indonesia. Each village had a different conservation program design. We surveyed people (n = 240) to determine their motivations for and behavior changes relative to orangutan and orangutan habitat (forest) protection. Heteronomous motivations (e.g., income from tourism) led to greater self‐reporting of behavior change toward orangutan protection. However, they did not change self‐reported behavior toward forest (i.e., orangutan habitat) protection. The most effective approach to creating self‐reported behavior change throughout the community was a combination of autonomous and heteronomous motivations. Individuals who were heteronomously motivated to protect the orangutan were more likely to have changed attitudes than to have changed their self‐reported behavior. These findings demonstrate that the current paradigm of motivating communities in developing countries to adopt conservation behaviors primarily through monetary incentives and rewards should consider integrating autonomous motivational techniques that promote the intrinsic values of conservation. Such a combination has a greater potential to achieve sustainable and cost‐effective conservation outcomes. Our results highlight the importance of using in‐depth sociopsychological analyses to inform the design and implementation of community‐based conservation programs. 相似文献
49.
Feeling insulted? Examining end‐of‐work anger as a mediator in the relationship between daily illegitimate tasks and next‐day CWB 下载免费PDF全文
In this daily diary study, we investigated the within‐person relationship between daily illegitimate tasks and next‐day counterproductive work behavior (CWB). We explored a moderated mediation model where the link between illegitimate tasks and CWB is mediated by daily end‐of‐work anger, with daily time pressure moderating the relationship between illegitimate tasks and end‐of‐work anger. We collected data from 114 full‐time employees across 10 consecutive working days. Results showed that within individuals, daily illegitimate tasks positively predicted next‐day CWB, and the relationship was mediated by daily end‐of‐work anger. Further, daily time pressure moderated the relationship between daily illegitimate tasks and daily end‐of‐work anger with the relationship being stronger when daily time pressure was high. 相似文献
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