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361.
Wang D Hao Y Wang K Zhao Q Chen D Wei Z Zhang X 《Environmental science and pollution research international》2005,12(5):247-250
Background As the sole freshwater subspecies of finless porpoise (Neophocaena phocaenoides), the Yangtze finless porpoise (N. p. asiaeorientalis)
lives only in the middle and lower reaches of the Yangtze River and its appended Poyang and Dongting Lakes. As a result of
human activity on the river, including over and illegal fishing, pollution, transportation and dam construction, the population
of Yangtze finless porpoises has been steadily and rapidly decreasing during the past several decades, which leads the animal
to be endangered.
Methods For saving this unique animal from extinction, three corresponding measures, in situ conservation, ex situ conservation,
and intensifying breeding research in captivity, were proposed and have been implemented since the 1980s.
Results After successfully rearing the animals in captivity for almost nine years, the first Yangtze finless porpoise was successfully
born in captivity on July 5, 2005. The calf is male, with a body length of 69cm. This is the first freshwater cetacean ever
born in captivity.
Conclusion The successful birth of this calf confirms that it is possible to breed the Yangtze finless porpoise in captivity. Furthermore,
this will greatly benefit the conservation efforts, and also greatly bolster our on-going efforts to study the reproductivebiology
of these animals.
Recommendation More studies and efforts are expected to establish a sustainable, captive colony of the Yangtze finless porpoise, which will
not only greatly expand our knowledge about the reproduction biology of this animal, but also help to redeem the wild population
through a careful yearly 'soft releasing' process. 相似文献
362.
M. A. Gomarasca 《Environmental monitoring and assessment》1996,41(2):159-170
The special project RAISA (Advanced Researches for Innovation in Agricultural Systems) of the National Research Council of Italy concerns the development of new methodologies for the study and evaluation of the impact of agrotechnologies on the environment. In the project, several trans-disciplinary Units have worked together since 1990. The aim of the project is to define systems, using tools such as remote sensing and Geographical Information Systems, for decision making support in land planning and land use management, with particular attention to groudwater table pollution. The fundamental steps for evaluation of the impact of agrotechnologies on the Po river watershed, 75,000 km2 in northern Italy, and Tevere (Tiber) river watershed, 17.169 km2 in Central Italy are described here. The study concerns particular areas located in the western part of the Po River plain, where flooded rice is the main crop, and in the central plain of the Tevere basin where the risk of water pollution is considerable, due to small and medium sized swine breeding farms. The aspects considered were water pollution due to mineral nitrogen used to fertilize the rice crop and the nitrogen contained in the waste water from pig farms. For the Po river basin the methodology developed was based on the integration of satellite remote sensing images, and the available cartography, such as topographic and thematic maps, together with the hydrological and the toxicological data of the chemical fertilizers employed, summarized in maps of the groundwater table pollution hazard. A simpler evaluation was obtained in the Tevere river basin: the thematic layers were crossed in bi-directional matrices and the result merged with the map of the territorial distributionof the swine. In both cases the selected information was integrated and processed in Integrated sub-basin scale. The GISs led to the development of a user-friendly system for formalizing our knowledge of the degree of pollution hazard in simple and readable maps.Research supported by National Research Council of Italy, Special Project RAISA, sub-project N. 1 Paper N. 相似文献
363.
通过对哈素海1989年度丰、平水期7个样点底栖动物的采集调查,共鉴定出底栖动物34种(属),初步摸清了哈素海丰、平水期不同样点底栖动物群落结构特点及其数量变动情况,并根据调查所获得的生态学资料,分别应用Beck生物指数、Goodnight生物指数、Glcason生物指数及Shannon多样性指数对哈素海水质进行了生物学评价。 相似文献
364.
Rob De Vries 《Journal of Agricultural and Environmental Ethics》2006,19(5):469-493
Genetic engineering evokes a number of objections that are not directed at the negative effects the technique might have on the health and welfare of the modified animals. The concept of animal integrity is often invoked to articulate these kind of objections. Moreover, in reaction to the advent of genetic engineering, the concept has been extended from the level of the individual animal to the level of the genome and of the species. However, the concept of animal integrity was not developed in the context of genetic engineering. Given this external origin, the aim of this paper is to critically examine the assumption that the concept of integrity, including its extensions to the level of the genome and the species, is suitable to articulate and justify moral objections more specifically directed at the genetic engineering of animals. 相似文献
365.
Michael C. Morris 《Journal of Agricultural and Environmental Ethics》2006,19(5):495-514
Changes in attitudes toward animal welfare, with a greater emphasis on the importance of allowing animals to express normal patterns of behavior has led to an examination of the practice of keeping hens in battery cages. There is widespread scientific consensus that the conditions of confinement and the barren nature of battery cages severely restrict hens’ behavioral repertoire, and are thus detrimental to their welfare. The New Zealand Animal Welfare Act 1999, stipulates that animals must have “the opportunity to display normal patterns of behaviour.” In spite of this provision, the New Zealand government has not acted in phasing out battery cages, arguing instead that there is insufficient evidence that welfare will be improved by a phase-out. There is evidence of strong industry pressure on the government, and the use of tactics common in policy considerations where changes are resisted by powerful interests. It is important that policy processes are better managed so that welfare changes are based on both public preferences and scientific knowledge, and ways of doing this are discussed. 相似文献
366.
Stefan Aerts Dirk Lips Stuart Spencer Eddy Decuypere Johan De Tavernier 《Journal of Agricultural and Environmental Ethics》2006,19(1):67-76
When making an assessment of animal welfare, it is important to take environmental (housing) or animal-based parameters into
account. An alternative approach is to focus on the behavior and appearance of the animal, without making actual measurements
or quantifying this. None of these tell the whole story. In this paper, we suggest that it is possible to find common ground
between these (seemingly) diametrically opposed positions and argue that this may be the way to deal with the complexity of
animal welfare. The model will have to be acceptable for the different parties that will be affected by it and real benefits
for the animal should result from it. This will be the basis of a practical ethical approach. All this can be condensed into
a model that essentially is made up out of three basic elements: the classical welfare analysis with an existing welfare assessment
tool, an assessment of the stockholder, and an implementation of the Free Choice Profiling technique. This new framework does
not pretend to be a different or better animal welfare matrix; it is intended to integrate existing knowledge and to provide
a practical tool to improve animal welfare. It identifies whether there are welfare problems on a farm, if present whether
these problems are caused by the housing system or the stockholder, and what can be done to improve the situation. 相似文献
367.
M.?B.?M.?BrackeEmail author K.?H.?De?Greef H.?Hopster 《Journal of Agricultural and Environmental Ethics》2005,18(1):27-56
Continued concern for animal welfare may be alleviated when welfare would be monitored on farms. Monitoring can be characterized as an information system where various stakeholders periodically exchange relevant information. Stakeholders include producers, consumers, retailers, the government, scientists, and others. Valuating animal welfare in the animal-product market chain is regarded as a key challenge to further improve the welfare of farm animals and information on the welfare of animals must, therefore, be assessed objectively, for instance, through monitoring. Interviews with Dutch stakeholder representatives were conducted to identify their perceptions about the monitoring of animal welfare. Stakeholder perceptions were characterized in relation to the specific perspectives of each stakeholder. While producers tend to perceive welfare from a production point of view, consumers will use visual images derived from traditional farming and from the animals natural environments. Scientists perceptions of animal welfare are affected by the need to measure welfare with quantifiable parameters. Retailers and governments (policy makers) have views of welfare that are derived from their relationships with producers, consumers, non-governmental organizations (NGOs), and scientists. All interviewed stakeholder representatives stated that animal welfare is important. They varied in the extent to which they weighted economic considerations relative to concern for the animals welfare. Many stakeholders emphasized the importance of communication in making a monitoring system work. Overall, the perspectives for the development of a sustainable monitoring system that substantially improves farm animal welfare were assessed as being poor in the short term. However, a reliable system could be initiated under certain conditions, such as integrated chains and with influential and motivated stakeholders. A scheme is described with attention points for the development of sustainable monitoring systems for farm animal welfare in the long term. 相似文献
368.
Karsten Klint Jensen Jan Tind Sørensen 《Journal of Agricultural and Environmental Ethics》1998,11(2):85-100
This paper presents the idea of a decision-support system for a livestock farm, called “ethical accounting”, to be used as
an extension of traditional cost accounting. “Ethical accounting” seeks to make available to the farmer information about
how his decisions affect the interests of farm animals, consumers and future generations. Furthermore, “ethical accounting”
involves value-based planning. Thus, the farmer should base his choice of production plan on reflections as to his fundamental
objectives, and he should make his final decision only after having seriously considered the various consequences for the
affected parties.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
369.
不同资源环境梯度下吉林西部生态经济系统能值分析 总被引:1,自引:0,他引:1
利用能值方法,从东南-西北方向选取吉林西部长岭、乾安、大安、镇赉四县市进行不同资源环境梯度下生态经济系统演变的对比分析。结果表明1989-2001年研究区多项能值指标差异明显:①系统稳定性方面,降水相对较多的长岭和乾安稳定性强于镇赉和大安。能值密度及能值投入率为长岭>乾安>大安>镇赉。能值产出以及能值积累量呈增大趋势,增幅长岭>乾安>大安>镇赉;②系统产出结构变化显著,虽然种植业比例有所下降,但一直是长岭、乾安的主导产业,镇赉、大安畜牧业超过种植业成为主导产业,系统平均能值产出率为长岭(1.89)<乾安(1.96)<大安(1.99)<镇赉(2.29);③环境负载率长岭<乾安<大安<镇赉,可持续发展指数则相反;④资源环境条件尤其是降水是该区生态经济系统状态的重要影响因素。 相似文献
370.
宁夏盐池牧业生产系统的研究 总被引:1,自引:0,他引:1
本文采用系统科学的理论方法,详细地分析了盐池县牧业生产系统的内外关系与存在问题及相应的战略对策;结合对现实农业生态系统的能流与物流的定性分析,指出合理运行牧业生产系统,是使盐池县草原恢复、生态维持及农村经济发展的重要途径。 相似文献