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951.
The anti-predator responses of an animal may depend on the species of predator attacking. For example, ground-dwelling monkeys
respond with different warning calls in response to attacks from hawks from above vs attacks from leopards at the side. In
grouping animals, it has usually been assumed that the best anti-predator behavior against most predators is to move toward
the center of a group. However, little work has been done to study positioning of individuals in response to different predators
and whether it might be influenced by gender or body condition. An optimality model is developed that gives predictions for
how the needs of predator avoidance, drafting, and foraging could lead to one optimal location within the group. We then conducted
a laboratory experiment with individually marked whirligig beetles (Coleoptera: Gyrinidae). We exposed them to an aerial (bird)
or aquatic (fish) attack and determined changes in their distance to the front of groups at different speeds of water. We
found that female whirligigs occupied the front of a group in response to a fish attack in fast water, but the back after
an aerial bird attack, while the reverse was true for males. In slow water, different results were found; in response to a
bird attack, females were more likely to be found in the front compared with males. Body condition was not correlated to the
front/back position of either males or females before or after attacks in our study. 相似文献
952.
953.
A Framework for Evaluating the Effects of Human Factors on Wildlife Habitat: the Case of Giant Pandas 总被引:10,自引:0,他引:10
Jianguo Liu ‡ Zhiyun Ouyang † William W. Taylor Richard Groop § Yingchun Tan and Heming Zhang 《Conservation biology》1999,13(6):1360-1370
Abstract: To address the complex interactions between humans and wildlife habitat, we developed a conceptual framework that links human factors with forested landscapes and wildlife habitat. All the components in the framework are integrated into systems models that analyze the effects of human factors and project how wildlife habitat would change under different policy scenarios. As a case study, we applied this framework to the Wolong Nature Reserve in Sichuan Province (southwestern China), the largest home of the giant panda ( Ailuropoda melanoleuca ). We collected ecological and socioeconomic data with a combination of various methods ( field observations, aerial photographs, government documents and statistics, interviews, and household surveys) and employed geographic information systems and systems modeling to analyze and integrate the data sources. Human population size has increased by 66% and the number of households in the reserve has increased by 115% since 1975, when the reserve was established. During the same period, the quality and quantity of the giant panda habitat dramatically decreased because of increasing human activities such as fuelwood collection. Systems modeling predicted that under the status quo, human population in the reserve would continue to grow and cause more destruction of the remaining panda habitat, whereas reducing human birth rates and increasing human emigration rates would lower human population size and alleviate human impacts on the panda habitat. Furthermore, our simulations and surveys suggested that policies encouraging the emigration of young people would be more effective and feasible than relocating older people in reducing human population size and conserving giant panda habitat in the reserve. 相似文献
954.
Cristina A.R. De Carvalho Walter Leal Filho William H.G. Hale 《The Environmentalist》1999,18(4):223-229
This paper describes the problems encountered in developing environmental education in Federal protected areas in Brazil. Results of a survey on the current status of environmental education in four categories of Federal protected areas; namely national parks, biological reserves, ecological stations and environmental protection areas, are described and discussed. The study suggests that the development of environmental education in protected areas in the country has several limitations: financial resources, lack of training, material resources and a lack of policy on environmental education. It also identifies that some of these problems seem to be inter-related with those of the National System of Conservation Units of the country which may result in a retarding of the development of environmental education in such areas. 相似文献
955.
Jeremy S. Simmonds Andres Felipe Suarez-Castro April E. Reside James E. M. Watson James R. Allan Scott C. Atkinson Pasquale Borrelli Nigel Dudley Stephen Edwards Richard A. Fuller Edward T. Game Simon Linke Sean L. Maxwell Panos Panagos Philippe Puydarrieux Fabien Quétier Rebecca K. Runting Talitha Santini Laura J. Sonter Martine Maron 《Conservation biology》2023,37(3):e14040
Global efforts to deliver internationally agreed goals to reduce carbon emissions, halt biodiversity loss, and retain essential ecosystem services have been poorly integrated. These goals rely in part on preserving natural (e.g., native, largely unmodified) and seminatural (e.g., low intensity or sustainable human use) forests, woodlands, and grasslands. To show how to unify these goals, we empirically derived spatially explicit, quantitative, area-based targets for the retention of natural and seminatural (e.g., native) terrestrial vegetation worldwide. We used a 250-m-resolution map of natural and seminatural vegetation cover and, from this, selected areas identified under different international agreements as being important for achieving global biodiversity, carbon, soil, and water targets. At least 67 million km2 of Earth's terrestrial vegetation (∼79% of the area of vegetation remaining) required retention to contribute to biodiversity, climate, soil, and freshwater conservation objectives under 4 United Nations’ resolutions. This equates to retaining natural and seminatural vegetation across at least 50% of the total terrestrial (excluding Antarctica) surface of Earth. Retention efforts could contribute to multiple goals simultaneously, especially where natural and seminatural vegetation can be managed to achieve cobenefits for biodiversity, carbon storage, and ecosystem service provision. Such management can and should co-occur and be driven by people who live in and rely on places where natural and sustainably managed vegetation remains in situ and must be complemented by restoration and appropriate management of more human-modified environments if global goals are to be realized. 相似文献
956.
William L. Mostia 《Journal of Loss Prevention in the Process Industries》2010,23(6):799-805
Accidents in the process industries are extensively investigated to determine root causes, for lessons learned, and many times in search of the “guilty”. Accidents are seldom simple and most accidents have human elements that led to or facilitated the accident. Many times the people involved in these accidents, when considered individually on their merit, would be considered “good” people yet “bad things” (accidents) still occur.Human errors can be classified as individual, group, and organizational. Individual human errors have been addressed in a number of studies and papers. Many of these classify human errors and treat them probabilistically or cognitively. Less has been said regarding the individual psychological/sociological response/interaction mechanisms that might contribute to an industrial accident. These elements also contribute to a lack of situational awareness which often plays a large part in human error. Group and organizational interactions/dynamics can also contribute negatively to situational awareness and to the chain of events of an accident. Organization errors, which are typically latent, can also facilitate an accident and are many times people enabled for personal and business vested interests.This paper will discuss the effect of human error at the practical plant level in contributing to accidents in the process industries from individual, group, and organizational perspective. The discussion will include psychological/sociological response/interaction mechanisms that can contribute to situational awareness and human error. It will also discuss how complexity, veracity, and quantity of available information can affect the human decision-making process leading to mistakes.Accidents are seldom simple and most accidents have a number of elements that led to or facilitated the accident. When looking at individual elements probabilistically, multiplying probabilities together, it is hard to see how an accident could have occurred. A common refrain “That’s double jeopardy and we don’t have to consider that” is essentially a qualitative probabilistic analysis. Yet we have cases of triple, quadruple, n-jeopardy occurring to cause accidents. The paper will discuss the superimposition of causes and a similar concept of functional resonance in causing accidents. 相似文献
957.
We review and discuss an Organizational Neuroscience perspective on management science research. Reviewing recent findings in the brain sciences, we provide concrete examples of how an organizational neuroscience perspective can advance organizational behavior research. We conclude that this new paradigm offers powerful insights and tools that complement traditional organizational research. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
958.
Importance of Riparian Forests in Urban Catchments Contingent on Sediment and Hydrologic Regimes 总被引:1,自引:0,他引:1
Roy AH Freeman MC Freeman BJ Wenger SJ Ensign WE Meyer JL 《Environmental management》2006,37(4):523-539
Forested riparian corridors are thought to minimize impacts of landscape disturbance on stream ecosystems; yet, the effectiveness
of streamside forests in mitigating disturbance in urbanizing catchments is unknown. We expected that riparian forests would
provide minimal benefits for fish assemblages in streams that are highly impaired by sediment or hydrologic alteration. We
tested this hypothesis in 30 small streams along a gradient of urban disturbance (1–65% urban land cover). Species expected
to be sensitive to disturbance (i.e., fluvial specialists and “sensitive” species that respond negatively to urbanization)
were best predicted by models including percent forest cover in the riparian corridor and a principal components axis describing
sediment disturbance. Only sites with coarse bed sediment and low bed mobility (vs. sites with high amounts of fine sediment)
had increased richness and abundances of sensitive species with higher percent riparian forests, supporting our hypothesis
that response to riparian forests is contingent on the sediment regime. Abundances of Etheostoma scotti, the federally threatened Cherokee darter, were best predicted by models with single variables representing stormflow (r2 = 0.34) and sediment (r2 = 0.23) conditions. Lentic-tolerant species richness and abundance responded only to a variable representing prolonged duration
of low-flow conditions. For these species, hydrologic alteration overwhelmed any influence of riparian forests on stream biota.
These results suggest that, at a minimum, catchment management strategies must simultaneously address hydrologic, sediment,
and riparian disturbance in order to protect all aspects of fish assemblage integrity. 相似文献
959.
Atwill ER Pereira MD Alonso LH Elmi C Epperson WB Smith R Riggs W Carpenter LV Dargatz DA Hoar B 《Journal of environmental quality》2006,35(1):200-206
The first step in assessing the risk of water contamination by Cryptosporidium parvum oocysts from feedlot cattle (Bos taurus) production systems is to quantify the number of C. parvum oocysts present in the fecal material deposited by feedlot cattle. Our primary objective for this project was to estimate the daily environmental load of C. parvum oocysts in fecal material deposited by feedlot cattle from across the central and western USA. Our secondary goal was to genotype isolates of C. parvum from feedlot cattle to help facilitate proper identification of mammalian sources of waterborne C. parvum. Based on 5274 fecal samples from 22 feedlots in seven states (California, Washington, Colorado, Oklahoma, Texas, Nebraska, and South Dakota), we estimated a point prevalence of C. parvum of 0.99 to 1.08% in fecal material from feedlot pens from a wide range of climates and a diverse range of feedlot management systems. On average, fresh fecal material from throughout feedlot systems (recent arrivals to nearing slaughter) contained about 1.3 to 3.6 oocysts/g feces, which roughly translates to about 2.8 x 10(4) to 1.4 x 10(5) oocysts/animal per day. 相似文献
960.
Alastair Franke Knud Falk Kevin Hawkshaw Skip Ambrose David L. Anderson Peter J. Bente Travis Booms Kurt K. Burnham Suzanne Carrire Johan Ekenstedt Ivan Fufachev Sergey Ganusevich Kenneth Johansen Jeff A. Johnson Sergey Kharitonov Pertti Koskimies Olga Kulikova Peter Lindberg Berth-Ove Lindstrm William G. Mattox Carol L. McIntyre Svetlana Mechnikova Dave Mossop Sren Mller lafur K. Nielsen Tuomo Ollila Arve stlyngen Ivan Pokrovsky Kim Poole Marco Restani Bryce W. Robinson Robert Rosenfield Aleksandr Sokolov Vasiliy Sokolov Ted Swem Katrin Vorkamp 《Ambio》2020,49(3):784-785
While collating contributions and comments from 36 researchers, the coordinating authors accidentally omitted Dr. Suzanne Carrière from the list of contributing co-authors. Dr. Carrière’s data are described in Tables 1 and 3, Figure 2 and several places in the narrative. The new author list is thus updated in this article. 相似文献