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131.
Eljarrat E  Caixach J  Rivera J 《Chemosphere》2002,46(9-10):1403-1407
As result of a study to control feedstuff, analyses were carried out to evaluate the contamination caused by PCDDs and PCDFs in different animal feed ingredients. Thirty two samples were selected, including ingredients of animal and mineral origin. For samples of mineral origin, some additives widely employed as binder and anticaking agents, such as bentonite, damoline, kaolin, magnesite, sepiolite and zeolite were selected. And, for ingredients of animal origin, samples of hemoglobin, animal fat, fish oil, fish meal and meat and bone meal were analyzed. The levels ranged from 0.52 to 9.08 pg WHO-TEQ/g fat for samples of animal origin, and from 0.05 to 460.59 pg WHO-TEQ/g for samples of mineral origin. The higher concentrations were observed for the kaolin samples that presented high levels of dioxin contamination.  相似文献   
132.
Abad E  Llerena JJ  Sauló J  Caixach J  Rivera J 《Chemosphere》2002,46(9-10):1417-1421
Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in some additives widely employed as binder and anti-caking agents in feedstuffs, such as kaolin, bentonite, zeolite, etc. with an special attention on sepiolite samples. Owing to their physico-chemical properties, the little information of these materials reported in the literature, the variability of PCDDs/PCDFs found in a preliminary evaluation and the absence of reference materials highlighted further research needed. Therefore, an extensive study on the analytical procedures based on the classical methods was performed with sepiolite samples. The study includes evaluation of reproducibility and repeatibility. To this end, a series of intra-day and nine inter-day analysis were made. The methodolgy was also assessed against the sample size and series of 12.5, 25, 37.5 and 50 g were analyzed. In all cases, the results confirmed good correlation with the parameters evaluated.  相似文献   
133.
134.
从强可持续理念出发,基于改进的SFA模型对中国2004-2015年30个省份的绿色创新效率及生态福利绩效值进行测度,结合耦合协调度模型对两系统的耦合协调度进行分析,同时考虑其空间特征及演变规律。结果表明:(1)中国生态福利绩效值在空间上已形成由北京—浙江—广东—陕西构成的四角极点支撑,并不断向沿线地区辐射。(2)2004-2015年两系统的耦合度均值C∈[0.666, 0.680],整体处于较高强度耦合阶段,而协调度均值则整体处于初级协调阶段 (D∈[0.512, 0.565]),未来仍有较大的优化空间。(3)从空间格局上看,地区间的耦合协调度差距显著,高值区(中高级协调)主要集中在东部沿海地区,且已形成由广东—浙江两个高级协调发展极核辐射的“U”型发展轴带;初级协调阶段的地区连片扩张趋势明显。相比较而言,西北地区仍处于中国绿色创新效率与生态福利绩效耦合协调的最后梯队,受周边地区辐射影响较小,增速缓慢。  相似文献   
135.
This paper develops a valuation method which generates consistent and systematic estimates of people's preferences for complex multi-attribute goods by inextricably linking auction bids with conjoint ratings. The advantage of the valuation approach is that it permits the estimation of people's values for many potential goods, allows one to decompose people's values for a good into its sub-components, and permits the study of preference heterogeneity without distributional assumptions. We apply the method to an important and increasingly controversial topic: animal welfare. The method is used to determine people's preferences for eggs and pork produced from different production systems. Data from experiments conducted in three diverse U.S. locations (Chicago, IL; Dallas, TX; and Wilmington, NC) indicates that people are, on average, willing to pay $0.95 more for a dozen eggs raised in an aviary, pasture system vs. a cage system, and are willing to pay $2.02 more for two-pounds of pork chops raised in a pasture system as opposed to a crate system.  相似文献   
136.
The role of agent-based models in wildlife ecology and management   总被引:2,自引:0,他引:2  
Conservation planning of critical habitats for wildlife species at risk is a priority topic that requires the knowledge of how animals select and use their habitat, and how they respond to future developmental changes in their environment. This paper explores the role of a habitat-modeling methodological approach, agent-based modeling, which we advocate as a promising approach for ecological research. Agent-based models (ABMs) are capable of simultaneously distinguishing animal densities from habitat quality, can explicitly represent the environment and its dynamism, can accommodate spatial patterns of inter- and intra-species mechanisms, and can explore feedbacks and adaptations inherent in these systems. ABMs comprise autonomous, individual entities; each with dynamic, adaptive behaviors and heterogeneous characteristics that interact with each other and with their environment. These interactions result in emergent outcomes that can be used to quantitatively examine critical habitats from the individual- to population-level. ABMs can also explore how wildlife will respond to potential changes in environmental conditions, since they can readily incorporate adaptive animal-movement ecology in a changing landscape. This paper describes the necessary elements of an ABM developed specifically for understanding wildlife habitat selection, reviews the current empirical literature on ABMs in wildlife ecology and management, and evaluates the current and future roles these ABMs can play, specifically with regards to scenario planning of designated critical habitats.  相似文献   
137.
Selecting suitable sites for animal waste application using a raster GIS   总被引:1,自引:0,他引:1  
Rapid growth of intensive animal industries in southeast Queensland, Australia, has led to large volumes of animal waste production, which posses serious environmental problems in the Murray Darling Basin (MDB). This study presents a method of selecting sites for the safe application of animal waste as fertiliser to agricultural land. A site suitability map for the Westbrook subcatchment within the MDB was created using a geographic information system (GIS)-based weighted linear combination (WLC) model. The factors affecting the suitability of a site for animal waste application were selected, and digital data sets derived from up to 1:50,000 scale maps were acquired. After initial preprocessing, digital data sets were clipped to the size of the delineated subcatchment boundary producing input factors. These input factors were weighted using the analytical hierarchy process (AHP) that employed an objectives-oriented comparison (OOC) technique to formulate the pairwise comparison matrix. The OOC technique, which is capable of deriving factor weight independently, formulated the weight derivation process by making it more logical and systematic. The factor attributes were classified into multiple classes and weighted using the AHP. The effects of the number of input factors and factor weighting on the areal extent and the degree of site suitability were examined. Due to the presence of large nonagricultural and residential areas in the subcatchment, only 16% of the area was found suitable for animal waste application. The areal extent resulting from this site suitability assessment was found to be dependent on the areal constraints imposed on each input factor, while the degree of suitability was principally a function of the weight distribution between the factors.  相似文献   
138.
动物伦理学研究   总被引:1,自引:0,他引:1  
为了构建动物伦理学,笔者考察并概括了西方动物伦理研究的本质和关键问题,认为:动物伦理学是关于人与动物关系的伦理信念、道德态度和行为规范的理论体系,是一门尊重动物的价值和权利的新的伦理学说。它的产生具有坚实的科学基础、伦理基础和现实迫切性。  相似文献   
139.
After satisfying their quantitative and qualitative needs as regards nutrition, consumers in developed countries are becoming more involved in the ethical aspects of food production, especially when it relates to animal products. Social demands for respecting animal welfare in housing systems are increasing rapidly, as is social awareness of human responsibility towards farm animals. Many studies have been conducted on animal welfare measurement in different production systems, but the available information for small ruminants remains insufficient. In this study, a 75 criteria-evaluation tool has been set up on the basis of the five freedoms concept. Animal welfare considerations have been analyzed in 25 documents, including labeling schemes, regulations, and recommendations from different European countries. The results show many differences between regular and organic small ruminant farming standards. Emergency measures are generally lacking. A weak representation of psychological aspects of animal welfare, especially by the current European legislation, is highlighted.  相似文献   
140.
Procedures that increase the sustainability of agriculture often result in animals being treated more humanely:both livestock in animal and mixed farming and wildlife in arable farming. Equally, procedures ensuring humane treatment of farm animals often increase sustainability, for example in disease control and manure management. This overlap between sustainability and humaneness is not coincidental. Both approaches can be said to be animal centered, to be based on the fact that animal production is primarily a biological process. Proponents of both will gain from recognition of commonality and development of cooperation. A collaborative approach to humane sustainable agriculture will benefit animals, people, and the environment.  相似文献   
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