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921.
Understanding the conditions that force the implementation of management actions and their efficiency is crucial for conservation of endangered species. Wildlife managers are widely and increasingly using food supplementation for such species because the potentially immediate benefits may translate into rapid conservation improvements. Supplementary feeding can also pose risks eventually promoting undesired, unexpected, subtle, or indirect, and often unnoticed, effects that are generally poorly understood. For two decades, intensive food supplementation has been used in attempting to improve the breeding productivity of the Spanish Imperial Eagle, Aquila adalberti, one of the most endangered birds of prey in the world. Here, we examined the impact of this intensive management action on nestling health, including contamination, immunodepression, and acquisition of disease agents derived from supplementation techniques and provisioned food. Contrary to management expectations, we found that fed individuals were often inadvertently "medicated" with pharmaceuticals (antibiotics and antiparasitics) contained in supplementary food (domestic rabbits). Individuals fed with medicated rabbits showed a depressed immune system and a high prevalence and richness of pathogens compared with those with no or safe supplementary feeding using non-medicated wild rabbits. A higher presence of antibiotics (fluoroquinolones) was found in sick as opposed to healthy individuals among eaglets with supplementary feeding, which points directly toward a causal effect of these drugs in disease and other health impairments. This study represents a telling example of well-meaning management strategies not based on sound scientific evidence becoming a "contraindicated" action with detrimental repercussions undermining possible beneficial effects by increasing the impact of stochastic factors on extinction risk of endangered wildlife. 相似文献
922.
Electrothermal atomic absorption spectrometry methods with Zeeman effect background correction (Z-GFAAS) for determination
of As, Sb, Se, Ag, Cd, Pb, Cu, Fe, Zn, Cr, and Ni in water and sludge samples were developed. The measurements using Z-GFAAS
and variable magnetic field at the three-field dynamic mode permit the sensitivity adaptation for higher analytical concentrations.
Calibration ranges were expanded over two orders of magnitude within one measurement run by the applying three-field dynamic
mode of this correction system. There are presented calibration data, furnace programs, modifiers, and microwave digestion
programs of the obviously monitored elements in the environmental samples. Very low detection limits (3σ criterion) were obtained.
Quality assurance was checked by the suitable CRM. The study brings simultaneous determination of the samples with different
element concentration range and different sample matrixes, as an important application information for an analyst working
in the area of the eco-analytical research. 相似文献
923.
Land degradation assessment by geo-spatially modeling different soil erodibility equations in a semi-arid catchment 总被引:1,自引:0,他引:1
Saygın SD Basaran M Ozcan AU Dolarslan M Timur OB Yilman FE Erpul G 《Environmental monitoring and assessment》2011,180(1-4):201-215
Land degradation by soil erosion is one of the most serious problems and environmental issues in many ecosystems of arid and semi-arid regions. Especially, the disturbed areas have greater soil detachability and transportability capacity. Evaluation of land degradation in terms of soil erodibility, by using geostatistical modeling, is vital to protect and reclaim susceptible areas. Soil erodibility, described as the ability of soils to resist erosion, can be measured either directly under natural or simulated rainfall conditions, or indirectly estimated by empirical regression models. This study compares three empirical equations used to determine the soil erodibility factor of revised universal soil loss equation prediction technology based on their geospatial performances in the semi-arid catchment of the Saraykoy II Irrigation Dam located in Cankiri, Turkey. A total of 311 geo-referenced soil samples were collected with irregular intervals from the top soil layer (0-10?cm). Geostatistical analysis was performed with the point values of each equation to determine its spatial pattern. Results showed that equations that used soil organic matter in combination with the soil particle size better agreed with the variations in land use and topography of the catchment than the one using only the particle size distribution. It is recommended that the equations which dynamically integrate soil intrinsic properties with land use, topography, and its influences on the local microclimates, could be successfully used to geospatially determine sites highly susceptible to water erosion, and therefore, to select the agricultural and bio-engineering control measures needed. 相似文献
924.
925.
Jorge Alberto Achcar Josmar Mazucheli Emílio Augusto Coelho-Barros 《Environmental and Ecological Statistics》2011,18(2):315-329
In this paper we present a hierarchical Bayesian analysis for a predator–prey model applied to ecology considering the use
of Markov Chain Monte Carlo methods. We consider the introduction of a random effect in the model and the presence of a covariate
vector. An application to ecology is considered using a data set related to the plankton dynamics of lake Geneva for the year
1990. We also discuss some aspects of discrimination of the proposed models. 相似文献
926.
Introduction
This study examined the impact of the British Petroleum (BP) Baker Panel Report, reviewing the March 2005 BP-Texas City explosion, on the field of process safety.Method
Three hundred eighty-four subscribers of a process safety listserv responded to a survey two years after the BP Baker Report was published.Results
Results revealed respondents in the field of process safety are familiar with the BP Baker Report, feel it is important to the future safety of chemical processing, and believe that the findings are generalizable to other plants beyond BP-Texas City. Respondents indicated that few organizations have administered the publicly available BP Process Safety Culture Survey. Our results also showed that perceptions of contractors varied depending on whether respondents were part of processing organizations (internal perspective) or government or consulting agencies (external perspective).Conclusions
This research provides some insight into the beliefs of chemical processing personnel regarding the transportability and generalizability of lessons learned from one organization to another.Impact on Industry
This study has implications for both organizational scientists and engineers in that it reveals perceptions about the primary mechanism used to share lessons learned within one industry about one major catastrophe (i.e., investigation reports). This study provides preliminary information about the perceived impact of a report such as this one. 相似文献927.
Alberto Megías Antonio Maldonado Andrés Catena Leandro L. Di Stasi Jesús Serrano Antonio Cándido 《Safety Science》2011,49(10):1388-1393
In road safety literature the effects of emotional content and salience of advertising billboards have been scarcely investigated. The main aim of this work was to uncover how affect-laden roadside advertisements can affect attention – eye-movements – and subsequent risky decisions – braking – on the Honda Riding Trainer motorcycle simulator. Results indicated that the number of fixations and total fixation time elicited by the negative and positive emotional advertisements were larger than the neutral ones. At the same time, negative pictures got later gaze disengagement than positive and neutral ones. This attentional capture results in less eye fixation times on the road relevant region, where the important driving events happen. Finally, the negative emotional valence advertisements sped up braking on subsequent risky situations. Overall results demonstrated how advertisements with emotional content modulate attention allocation and driving decisions in risky situations and might be helpful for designing roadside advertisements regulations and risk prevention programs. 相似文献
928.
This article sets outs a generalized utility model for the diagnosis and prediction of accidents among the Spanish workforce. Based on observational data classified into a risk–injury contingency table (19 × 19), we have summarized the accident rate of all Spanish companies over an 11-year period (75,19,732 accidents). By using correspondence analysis a structure composed of three axes can be obtained, the combination of which identifies three separate risk and injury groups, which we use as a general Spanish pattern. The relationships of greater affinity or likelihood amongst the risks and injuries identified in the pattern facilitate decision-making at the risk-assessment stage in Spanish companies. Each risk–injury group has its own characteristics, interpretable within the phenomenological framework of the accident.The main advantage of this model is its potential application to any other country and the feasibility of contrasting results from different countries. One limiting factor, however, is that the model currently lacks a common classification frame for risks and injuries which would enhance this contrast. The aim of this model is to automatically manage work-related accidents at a national level. 相似文献
929.
Rosa María Arnaldo Valdés Fernando Gómez Comendador Luis Mijares Gordún Francisco J. Sáez Nieto 《Safety Science》2011,49(5):633-650
The risks of landing overrun (LDOR – LanDing OverRun), Take-off Overrun (TOOR – Take-Off OverRun) and landing undershoot (LDUS – LanDing UnderShoot) are dependent on multiple factors related to operating conditions. These include wind, runway surface conditions, landing or take-off distances required, the presence of obstacles, runway distance available, the existence and dimensions of runway safety areas.In this paper we propose risk models for runway overrun and landing undershoot, using a probabilistic approach. These models are supported by historical data on accidents in the area around the runway and will enable us to determine if the risk level is acceptable or whether action must be taken to mitigate such risks at a given airport. Furthermore, these models permit comparison of the results of different risk mitigation actions in terms of operational risk and safety.The principal advantage of this method is the high quality results obtained for a limited investment in terms of time, computing power and data. As such the method is extremely practical and easy to apply in aerodrome planning, development and operation. 相似文献
930.