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161.
Insights into consumer behavior, hazards of inappropriate disposal, and opportunities to reclaim valuable resources 相似文献
162.
Oliver C. Stringham Adam Toomes Aurelie M. Kanishka Lewis Mitchell Sarah Heinrich Joshua V. Ross Phillip Cassey 《Conservation biology》2021,35(4):1130-1139
The unrivaled growth in e-commerce of animals and plants presents an unprecedented opportunity to monitor wildlife trade to inform conservation, biosecurity, and law enforcement. Using the internet to quantify the scale of the wildlife trade (volume and frequency) is a relatively recent and rapidly developing approach that lacks an accessible framework for locating relevant websites and collecting data. We produced an accessible guide for internet-based wildlife trade surveillance. We detailed a repeatable method involving a systematic internet search, with search engines, to locate relevant websites and content. For data collection, we highlight web-scraping technology as an efficient way to collect data in an automated fashion at regularly timed intervals. Our guide is applicable to the multitude of trade-based contexts because researchers can tailor search keywords for specific taxa or derived products and locations of interest. We provide information for working with the diversity of websites used in wildlife trade. For example, to locate relevant content on social media (e.g., posts or groups), each social media platform should be examined individually via the site's internal search engine. A key advantage of using the internet to study wildlife trade is the relative ease of access to an increasing amount of trade-related data. However, not all wildlife trade occurs online and it may occur on unobservable sections of the internet. 相似文献
163.
Investigating predator–prey relationships is an important component for identifying and understanding the factors that influence
the structure and function of ecosystems. Mesopredators, defined as mid-level predators, have a profound effect on ecosystem
structure by contributing an important link between apex predators and lower trophic levels. The diet of two elasmobranch
mesopredators, Squalus acanthias and Mustelus antarcticus, was investigated in three locations in south-east Tasmania. Squalus acanthias consumed predominantly pelagic teleosts and cephalopods, while M. antarcticus predominantly consumed benthic crustaceans. As a result, there was low dietary and niche overlap between the two species.
There was however evidence of intra-specific dietary variations between locations for both the species. This study has contributed
to a better understanding of the top-down dynamics of the food web in coastal Tasmania, by providing important dietary information
of two abundant mesopredators. In addition, the similar dietary patterns for S. acanthias and other Mustelus species over much of their global range suggest they may be consistent in their trophic roles across systems, with limited
competition between these two sympatric mesopredators to be expected. 相似文献
164.
A multispecies test of source–sink indicators to prioritize habitat for declining populations
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Julie A. Heinrichs Joshua J. Lawler Nathan H. Schumaker Chad B. Wilsey Kira C. Monroe Cameron L. Aldridge 《Conservation biology》2018,32(3):648-659
For species at risk of decline or extinction in source–sink systems, sources are an obvious target for habitat protection actions. However, the way in which source habitats are identified and prioritized can reduce the effectiveness of conservation actions. Although sources and sinks are conceptually defined using both demographic and movement criteria, simplifications are often required in systems with limited data. To assess the conservation outcomes of alternative source metrics and resulting prioritizations, we simulated population dynamics and extinction risk for 3 endangered species. Using empirically based habitat population models, we linked habitat maps with measured site‐ or habitat‐specific demographic conditions, movement abilities, and behaviors. We calculated source–sink metrics over a range of periods of data collection and prioritized consistently high‐output sources for conservation. We then tested whether prioritized patches identified the habitats that most affected persistence by removing them and measuring the population response. Conservation decisions based on different source–sink metrics and durations of data collection affected species persistence. Shorter time series obscured the ability of metrics to identify influential habitats, particularly in temporally variable and slowly declining populations. Data‐rich source–sink metrics that included both demography and movement information did not always identify the habitats with the greatest influence on extinction risk. In some declining populations, patch abundance better predicted influential habitats for short‐term regional persistence. Because source–sink metrics (i.e., births minus deaths; births and immigrations minus deaths and emigration) describe net population conditions and cancel out gross population counts, they may not adequately identify influential habitats in declining populations. For many nonequilibrium populations, new metrics that maintain the counts of individual births, deaths, and movement may provide additional insight into habitats that most influence persistence. 相似文献
165.
Responses of soil microbial communities to water stress: results from a meta-analysis 总被引:9,自引:0,他引:9
Soil heterotrophic respiration and nutrient mineralization are strongly affected by environmental conditions, in particular by moisture fluctuations triggered by rainfall events. When soil moisture decreases, so does decomposers' activity, with microfauna generally undergoing stress sooner than bacteria and fungi. Despite differences in the responses of individual decomposer groups to moisture availability (e.g., bacteria are typically more sensitive than fungi to water stress), we show that responses of decomposers at the community level are different in soils and surface litter, but similar across biomes and climates. This results in a nearly constant soil-moisture threshold corresponding to the point when biological activity ceases, at a water potential of about -14 MPa in mineral soils and -36 MPa in surface litter. This threshold is shown to be comparable to the soil moisture value where solute diffusion becomes strongly inhibited in soil, while in litter it is dehydration rather than diffusion that likely limits biological activity around the stress point. Because of these intrinsic constraints and lack of adaptation to different hydro-climatic regimes, changes in rainfall patterns (primary drivers of the soil moisture balance) may have dramatic impacts on soil carbon and nutrient cycling. 相似文献
166.
Benjamin F. Clark Joshua J. Amiel Richard Shine Daniel W. A. Noble Martin J. Whiting 《Behavioral ecology and sociobiology》2014,68(2):239-247
The ability of an animal to acquire, process and learn from information in their environment is thought to be fundamental to fitness. We currently have a poor understanding of the learning ability of young animals within the first few months of their life, the types of learning they use and the extent of their learning ability. Furthermore, an animal’s developmental environment, such as nest incubation temperature, may profoundly influence motor and cognitive skills. We first tested the ability of hatchling three-lined skinks (Bassiana duperreyi) incubated at ‘hot’ and ‘cold’ temperatures to solve an instrumental (motor) task before assessing their ability to learn colour associations in a multi-stage instrumental task, with a choice reversal. While 53 (88.3 %) lizards successfully completed the training phase, 14 (46.7 %) of the ‘hot’ incubated and none of the ‘cold’ incubated lizards successfully completed the instrumental task. Thirteen of these lizards rapidly learnt to discriminate colours, and this culminated in eight individuals successfully completing a choice reversal. Hatchling B. duperreyi demonstrated surprisingly rapid learning, and these results highlight the potentially important role of cognition during development and ultimately, in fitness. 相似文献
167.
Joshua E. Cinner Michele L. Barnes Georgina G. Gurney Stewart Lockie Cristian Rojas 《Conservation biology》2021,35(3):816-823
Markets are increasingly being incorporated into many aspects of daily life and are becoming an important part of the conservation solution space. Although market-based solutions to environmental problems can result in improvements to conservation, a body of social science research highlights how markets may also have unforeseen consequences by crowding out or displacing 3 key types of behaviors potentially relevant to conservation, including people's willingness to engage in collective action and civic duty; tolerance for inflicting harm on others (third-party externalities); and desire for equity. Better understanding of the contexts and mechanisms through which this crowding out occurs and whether specific market-based instruments are more prone to different types of crowding out will be crucial to developing novel conservation initiatives that can reduce or prevent crowding out. 相似文献
168.
Australian bushfire safety policy does not require mandatory evacuation from bushfire as practiced in North America and other jurisdictions. Australian householders confronted with a bushfire threat must decide whether they remain and defend their property or evacuate. A better understanding of factors that influence householders’ decisions to self-evacuate can inform bushfire safety policy. Studies have identified variables that motivate evacuation from various hazards, including wildfire, but factors shaping the decision processes are not well understood. The Protective Action Decision Model (PADM) provided a theoretical framework of factors influencing protective response to hazard to analyse the actions of householders affected by two bushfires. Three factors that predict self-evacuation were identified: the perception that evacuation is effective in protecting personal safety; the receipt of official warnings; and perceived threat to property. These findings reinforce the importance of increasing householder awareness and sensitivity to the danger posed by bushfire; the adequacy of people’s bushfire preparedness; the effectiveness of early evacuation in protecting personal safety; and the potential persuasiveness of accurate, relevant and timely official warning messages in influencing safe evacuation from bushfire. 相似文献
169.
170.
Bioabsorbable soy protein plastic composites: Effect of polyphosphate fillers on water absorption and mechanical properties 总被引:7,自引:0,他引:7
The use of synthetic and natural bioabsorbable plastics has been severely limited due to their low stiffness and strength
properties as well as their strong tendency to absorb moisture. This research focused on the development of bioabsorbable
polyphosphate filler/soy protein plastic composites with enhanced stiffness, strength, and water resistance. Bioabsorbable
polyphosphate fillers, biodegradable soy protein isolate, plasticizer, and adhesion promoter were homogenized and compression-molded.
Physical, mechanical, and water absorption testing was performed on the molded specimens. Results showed improvements in stiffness,
strength, and water resistance with increasing polyphosphate filler content up to 20% by weight. Application of a coupling
agent produced further mechanical property enhancements and a dramatic improvement in water resistance, interpreted by an
interfacial chemical bonding model. Examination of the fracture surfaces of the materials revealed that the addition of the
polyphosphate fillers changed the failure mode from brittle to pseudo-ductile. These results suggest that these materials
are suitable for many load-bearing applications in both humid and dry environments where current soy protein plastics are
not usable. 相似文献