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31.
Ken Tan Tanya Latty Zongwenu Hu Zhengwei Wang Shuang Yang Weiweng Chen Benjamin P. Oldroyd 《Behavioral ecology and sociobiology》2014,68(1):13-20
Honey bee foragers need to asses and make trade-offs between a number of potentially conflicting floral attributes. Here, we investigate multi-attribute decision making in the eastern honey bee, Apis cerana, when foraging on food sources that varied in warmth and sucrose concentration. We show that foragers prefer warm (30 °C) sucrose solution over cool (10 °C) sucrose solution and concentrated (30 % w/w) sucrose solution over dilute (15 % w/w) sucrose solution. When we offered the preferred sucrose concentration (30 % w/w) at the less-preferred temperature (10 °C), and the less-preferred sucrose concentration (15 % w/w) at the preferred temperature (30 °C), foragers prioritized warmth by choosing the warmer, but lower concentration solution. When the temperature difference was less extreme, bees preferred more concentrated cooler syrup (30 % ww at 15 °C over 15 % 30 °C). However, the addition of a decoy item to the choice set had a significant effect on the bees' preferences. Our results highlight the critical importance of considering context effects when measuring the foraging preferences of animals. 相似文献
32.
Norbert P. Psuty Andrea Spahn Tanya M. Silveira William Schmelz 《Journal of Coastal Conservation》2014,18(5):515-528
Persistent erosion at Plumb Beach, New York, USA, has been countered by a series of isolated actions to stabilize the shoreline. Sediment placed at the erosion site has quickly been removed and re-deposited in downdrift locations to the detriment of the existing habitats. In a renewed effort to better understand the dimensions of change at Plumb Beach, detailed spatial analysis of shoreline displacement, dune-beach profile evolution, and sediment budget has been undertaken through intensive surveying and comparisons of Digital Elevation Models. Products derived from these surveys establish that the sector of maximum erosion has shifted downdrift and that the scale of the changes is twice the volume exchange as previously estimated. Improved knowledge of the dimensions and spatial distributions of the changes is used to create a focused approach that is functioning within the scale of the local sediment budget and reducing its impacts. 相似文献
33.
Exploring cases of gas and coal extraction in Australia and the U.S.A., this paper considers instances in which legal and political frameworks have been used to prioritise development interests and minimise opportunities for community objection. Two case studies illustrate the role of law and the influence of politics on environmental conflict, conflict resolution, and participation in decision-making associated with resource extraction. A range of barriers to meaningful community participation in land-use decision-making are exposed by combining legal and non-legal concepts of equity and justice with ideologies of democracy and representation. These include asymmetry in information and resources available to parties; instances of misrecognition of weaker participants; and examples of malrecognition, where community attempts to engage democratic rights of public participation were thwarted by the strategic and deliberate actions of both industry and government. This paper illustrates the limits of current legal approaches to addressing land-use conflict and contributes to the developing scholarship of environmental justice as an analytic framework for addressing complex environmental and social justice issues. 相似文献
34.
Christopher M. Weible Tanya Heikkila David P. Carter 《Journal of Environmental Policy & Planning》2017,19(2):115-134
Hydraulic fracturing and oil and natural gas development are possibly the most contentious energy and environmental issues to face the USA in the twenty-first century. One point of contention is the disclosure of fluids used in the hydraulic fracturing process. This paper analyses the Colorado 2011 policy requiring disclosure of hydraulic fracturing fluid information, considered one of the first comprehensive hydraulic fracturing disclosure policies in the country. We conduct an institutional analysis of the disclosure policy to understand how the policy establishes information flows and grants and restricts choices by targeted actors. We then analyse the opinions of people actively involved in hydraulic fracturing debates in Colorado to assess whether they view the disclosure policy as resolving problems. The institutional analysis illustrates how the policy allocates responsibilities in sending and receiving information and the opinion survey shows divergence in perceptions of its potential to resolve problems associated with chemical use or disclosure. Most respondents are in agreement that the new policy failed to build public trust of the hydraulic fracturing process. 相似文献
35.
We examined the interaction of genotype and environment on foraging-behavior development and forage choice in honeybees. High- and low-pollen-hoarding strains and unselected wild-type bees were co-fostered in pairs of colonies manipulated to differentially stimulate high and low pollen foraging. The high-pollen-foraging stimulus consisted of high amounts of larvae, a known stimulus for pollen foraging, plus low amounts of pollen, known to induce pollen foraging. The low-pollen-foraging stimulus consisted of low amounts of larvae plus high amounts of pollen. We estimated the median age at which bees initiated foraging, determined forage choice, and the quality and quantity of resources collected. High-strain bees consistently foraged at younger ages than workers from the other sources. High-strain bees appeared to be more sensitive to the pollen-foraging-stimulus treatments, showing greater differences in foraging age and behavior. Three-way interactions of genotype, pollen foraging stimulus, and colony pair (replicate) were statistically significant for most foraging variables measured suggesting that additional, unknown environmental factors also affect foraging behavior. Our results suggest there is a functional relationship between age of first foraging and forage choice with a strong genetic component that is modulated by colony environment. 相似文献
36.
Tanya Pankiw Robert E. Page Jr M. Kim Fondrk 《Behavioral ecology and sociobiology》1998,44(3):193-198
Foraging and the mechanisms that regulate the quantity of food collected are important evolutionary and ecological attributes
for all organisms. The decision to collect pollen by honey bee foragers depends on the number of larvae (brood), amount of
stored pollen in the colony, as well as forager genotype and available resources in the environment. Here we describe how
brood pheromone (whole hexane extracts of larvae) influenced honey bee pollen foraging and test the predictions of two foraging-regulation
hypotheses: the indirect or brood-food mechanism and the direct mechanism of pollen-foraging regulation. Hexane extracts of
larvae containing brood pheromone stimulated pollen foraging. Colonies were provided with extracts of 1000 larvae (brood pheromone),
1000 larvae (brood), or no brood or pheromone. Colonies with brood pheromone and brood had similar numbers of pollen foragers,
while those colonies without brood or pheromone had significantly fewer pollen foragers. The number of pollen foragers increased
more than 2.5-fold when colonies were provided with extracts of 2000 larvae as a supplement to the 1000 larvae they already
had. Within 1 h of presenting colonies with brood pheromone, pollen foragers responded to the stimulus. The results from this
study demonstrate some important aspects of pollen foraging in honey bee colonies: (1) pollen foragers appear to be directly
affected by brood pheromone, (2) pollen foraging can be stimulated with brood pheromone in colonies provided with pollen but
no larvae, and (3) pollen forager numbers increase with brood pheromone as a supplement to brood without increasing the number
of larvae in the colony. These results support the direct-stimulus hypothesis for pollen foraging and do not support the indirect-inhibitor,
brood-food hypothesis for pollen-foraging regulation.
Received: 5 March 1998 / Accepted after revision: 29 August 1998 相似文献
37.
Perceptions of climate change risks in primary resource use industries: a survey of the Canadian mining sector 总被引:2,自引:0,他引:2
James D. Ford Tristan Pearce Jason Prno Frank Duerden Lea Berrang Ford Maude Beaumier Tanya Smith 《Regional Environmental Change》2010,10(1):65-81
A survey documenting how climate change is perceived, experienced, and responded to in the Canadian mining sector was administered
to industry practitioners at the Prospectors & Developers Association of Canada annual meeting. Nine key findings from the
survey are discussed: (1) The Canadian mining sector is sensitive to climate-related conditions. (2) Climate change is perceived
to be having a negative impact on mining operations. (3) Companies are taking action to manage the current impacts. (4) Cost
and uncertainty are commonly identified barriers to adapting to current climate change. (5) Future climate change is expected
to have impacts for the industry. (6) Climate change projections are perceived as threats by the majority of respondents.
(7) Despite the perceived threat, companies are not currently taking action to plan for future impacts. (8) Cost and uncertainty
are commonly identified barriers to adapting to future climate change impacts. (9) The mining sector is currently making efforts
to reduce greenhouse gas emissions. The survey is exploratory in nature, establishing a baseline for targeted research to
assess in greater detail the vulnerability of mining to climate change. 相似文献
38.
Katherine R. M. Mackey Tanya Rivlin Arthur R. Grossman Anton F. Post Adina Paytan 《Marine Biology》2009,156(8):1531-1546
The spring bloom in seasonally stratified seas is often characterized by a rapid increase in photosynthetic biomass. To clarify
how the combined effects of nutrient and light availability influence phytoplankton composition in the oligotrophic Gulf of
Aqaba, Red Sea, phytoplankton growth and acclimation responses to various nutrient and light regimes were recorded in three
independent bioassays and during a naturally-occurring bloom. We show that picoeukaryotes and Synechococcus maintained a “bloomer” growth strategy, which allowed them to grow quickly when nutrient and light limitation were reversed.
During the bloom picoeukaryotes and Synechococcus appeared to have higher P requirements relative to N, and were responsible for the majority of photosynthetic biomass accumulation.
Following stratification events, populations limited by light showed rapid photoacclimation (based on analysis of cellular
fluorescence levels and photosystem II photosynthetic efficiency) and community composition shifts without substantial changes
in photosynthetic biomass. The traditional interpretation of “bloom” dynamics (i.e., as an increase in photosynthetic biomass)
may therefore be confined to the upper euphotic zone where light is not limiting, while other acclimation processes are more
ecologically relevant at depth. Characterizing acclimation processes and growth strategies is important if we are to clarify
mechanisms that underlie productivity in oligotrophic regions, which account for approximately half of the global primary
production in the ocean. This information is also important for predicting how phytoplankton may respond to global warming-induced
oligotrophic ocean expansion. 相似文献
39.
This study used a mixed methods approach to estimate whether a moral panic occurred after Hurricane Katrina forced the evacuations of more than 250,000 people to Houston, Texas. The study viewed data from the Houston Police Department combined with a qualitative review of references of criminal activity in local print media. In total, over 8,500 lines of text were analysed to discern themes associated with media representations of the influence of evacuees on the city of Houston. There was little evidence of statistically significant increases in crime over the months following the evacuations. There was, however, evidence that evacuees, principally from New Orleans, were blamed for perceived increases in violent crime and lawlessness. There are also significant policy implications for state, local and federal governments. In particular, the policies of the Federal Emergency Management Agency were blamed for at least some of the perceived crime attributed to Katrina evacuees. 相似文献
40.