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881.
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
882.
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
883.
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
884.
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
885.
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
886.
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
887.
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
888.
Charles J. Weschler William W Nazaroff 《Atmospheric environment (Oxford, England : 1994)》2010,44(30):3609-3620
Semivolatile organic compounds (SVOCs) are a major class of indoor pollutants. Understanding SVOC partitioning between the gas phase and settled dust is important for characterizing the fate of these species indoors and the pathways by which humans are exposed to them. Such knowledge also helps in crafting measurement programs for epidemiological studies designed to probe potential associations between exposure to these compounds and adverse health effects. In this paper, we analyze published data from nineteen studies that cumulatively report measurements of dustborne and airborne SVOCs in more than a thousand buildings, mostly residences, in seven countries. In aggregate, measured median data are reported in these studies for 66 different SVOCs whose octanol-air partition coefficients (Koa) span more than five orders of magnitude. We use these data to test a simple equilibrium model for estimating the partitioning of an SVOC between the gas phase and settled dust indoors. The results demonstrate, in central tendency, that a compound’s octanol-air partition coefficient is a strong predictor of its abundance in settled dust relative to its gas phase concentration. Using median measured results for each SVOC in each study, dustborne mass fractions predicted using Koa and gas-phase concentrations correlate reasonably well with measured dustborne mass fractions (R2 = 0.76). Combined with theoretical understanding of SVOC partitioning kinetics, the empirical evidence also suggests that for SVOCs with high Koa values, the mass fraction in settled dust may not have sufficient time to equilibrate with the gas phase concentration. 相似文献
889.
William P.L. Carter 《Atmospheric environment (Oxford, England : 1994)》2010,44(40):5324-5335
An updated version of the SAPRC-99 gas-phase atmospheric chemical mechanism, designated SAPRC-07, is described. The rate constants and reactions have been updated based on current data and evaluations, the aromatics mechanisms have been reformulated and are less parameterized, chlorine chemistry has been added, the method used to represent peroxy reactions has been reformulated to be more appropriate for modeling gas-phase secondary organic aerosol precursors, and representations for many types of VOCs have been added or improved. This mechanism was evaluated against the result of ~2400 environmental chamber experiments carried out in 11 different environmental chambers, including experiments to test mechanisms for over 110 types of VOCs. The performance in simulating the chamber data was generally satisfactory for most types of VOCs but some biases were seen in simulations of some types of experiments. The mechanism was used to derive updated MIR and other ozone reactivity scales for almost 1100 types of VOCs, though in most cases the changes in MIR values relative to SAPRC-99 were not large. This mechanism update results in somewhat lower predictions of ozone in one-day ambient model scenarios under low VOC/NOx conditions. The files needed to implement the mechanism and additional documentation is available at the SAPRC mechanism web site at http://www.cert.ucr.edu/~carter/SAPRC. 相似文献
890.
Although conceptually simple and often idealized, disentangling crop–livestock interactions typically proves more complex in practice. Part of the complexity arises from their changing nature along agricultural intensification gradients. Such interactions increase in scope when extensive systems intensify, but decline in importance as already intermediate systems intensify further. This changing nature of crop–livestock interactions in relation to the system’s developmental stage implies that these exchanges can both contribute but also undermine system sustainability. We examine crop–livestock interactions in the Indo-Gangetic Plains as an empirical case, drawing from village surveys to explore and illustrate these relations and implications along the agro-ecological gradient of this vast and important eco-region. Such an understanding is increasingly needed as adapting crop residue management practices is recognized as the key to address sustainability concerns in the prevailing rice–wheat systems and as a stepping stone towards conservation agriculture. The agricultural R&D community needs to incorporate this understanding more proactively into its R&D agenda if it is to succeed in sustaining productivity gains, improving rural livelihoods equitably, and securing environmental sustainability. 相似文献