共查询到17条相似文献,搜索用时 187 毫秒
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东南亚珠芽魔芋多苗接力生长特性及应用前景 总被引:4,自引:2,他引:2
以珠芽魔芋人工诱导开花进行规模化无性育种,可将魔芋繁殖系数从1位数提高约330倍;采用催苗技术让种子及叶面球茎提早出苗,可显著延长魔芋生长周期,使魔芋种植周期由3年缩短为1年;魔芋种子1年生长最高膨大率超过5000倍,当年即形成1180g球茎;魔芋叶面球茎最大膨大率超过100倍,两者种植一季魔芋即可用于加工.突破了魔芋繁殖系数低、膨大率低导致种植周期长的双重困局,显著降低了病害风险,大幅度缩短了魔芋种植周期,从而突破魔芋传统种植区域的地理限制,使魔芋总产量超常规增长. 相似文献
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贵州木本食用油料资源及其开发利用 总被引:9,自引:0,他引:9
对贵州野生特有和稀有的大宗木本食用油料的种类、分布、现状等进行了分析,提出了提高大宗食用木本油料经营水平,选择利用野生木本油料植物资源,加强特有和稀有资源的保护、驯化和繁殖等开发利用建议。 相似文献
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原油及产品对藻类毒性影响研究 总被引:1,自引:0,他引:1
藻类具有种类繁多,个体小,生长繁殖迅速,对毒物的毒性敏感等特点,它长时间在水中生长,能客观地反映原油及产品对水体污染所产生的毒害综合效应。实验室中毒性研究通常采用纯种藻类培养来评价油的急性和早期毒性影响。经过实验室研究及原油泄漏现场调查研究表明:在含油的生态系统中油能刺激藻类的生长。在油污染过的水体中,原油中的轻烃和较易挥发的组分对藻类的毒性影响最大,原油泄漏的短期毒性影响和二次影响同等重要,油对藻类种群结构也具有重要的毒性影响。 相似文献
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开发保健食品——魔芋 总被引:1,自引:0,他引:1
魔芋亦名鬼芋、南星 ,中药称“蛇六谷” ,为天南星科多年生草本植物 ,有暗红褐色肉质地下球状茎 ,原产于印度 ,在我国种植很早。魔芋块茎的粗蛋白质含量为 9 7%,比马铃薯高 1 6%;1 6种氨基酸总含量为 7 8%,比马铃薯高 59%;7种必需氨基酸总量为 2 5%,比马铃薯高 53 8%;能降 相似文献
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Rebecca Efroymson Henriette Jager Virginia Dale James Westervelt 《Environmental management》2009,44(6):1163-1179
A decision framework for setting management goals for species at risk is presented. Species at risk are those whose potential
future rarity is of concern. Listing these species as threatened or endangered could potentially result in significant restrictions
to activities in resource management areas in order to maintain those species. The decision framework, designed to foster
proactive management, has nine steps: identify species at risk on and near the management area, describe available information
and potential information gaps for each species, determine the potential distribution of species and their habitat, select
metrics for describing species status, assess the status of local population or metapopulation, conduct threat assessment,
set and prioritize management goals, develop species management plans, and develop criteria for ending special species management
where possible. This framework will aid resource managers in setting management goals that minimally impact human activities
while reducing the likelihood that species at risk will become rare in the near future. The management areas in many of the
examples are United States (US) military installations, which are concerned about potential restrictions to military training
capacity if species at risk become regulated under the US Endangered Species Act. The benefits of the proactive management
set forth in this formal decision framework are that it is impartial, provides a clear procedure, calls for identification
of causal relationships that may not be obvious, provides a way to target the most urgent needs, reduces costs, enhances public
confidence, and, most importantly, decreases the chance of species becoming more rare. 相似文献
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Summary This literature review indicates how little is known about the growth of introduced bacteria. The available data base is so sparse that one can only speculate on the environmental conditions and the physiological traits that are needed to permit bacterial growth. Although methods are available to label organisms so that their multiplication can be detected under natural conditions, those methods have not been used sufficiently often to provide a meaningful base of information to allow a definition of conditions that favor multiplication of particular species or the organisms that are likely to proliferate in particular environments. However, because methods exist to monitor microbial growth, and new and better methods can be developed easily, it should not be difficult—provided research funds are made available—to expand greatly the data base and provide adequate information to be used for predicting the behavior of genetically engineered organisms in nature. 相似文献
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济南地区直翅目昆虫资源及其开发利用 总被引:4,自引:3,他引:1
本文报道了济南地区直翅目昆虫资源的种类组成,提出为害严重种类、优势种类、传统利用种类及易于捕捉或饲养种类共24种,可作为本地区开发直翅目昆虫资源的首选类群。根据资源的生物学特性,本文讨论了开发利用的途径与措施 相似文献
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Amitrajeet A. Batabyal 《Journal of environmental management》1998,52(4):373-378
The importance of the notion of resilience in determining the static and the intertemporal behaviour of jointly determined ecological-economic systems has long been recognized by ecologists. This notwithstanding, there are very few formal studies of such systems which explicitly analyse the ecological and the economic aspects of the problem. Consequently, this paper has two objectives. First, a new stationary probability-based method is proposed to characterize the notion of ecological resilience. Next, this characterization is used to study the problem of optimal species conservation. 相似文献
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Victoria A. Braithwaite Felicity Huntingford Ruud van den Bos 《Journal of Agricultural and Environmental Ethics》2013,26(1):7-23
Increasing public concern for the welfare of fish species that human beings use and exploit has highlighted the need for better understanding of the cognitive status of fish and of their ability to experience negative emotions such as pain and fear. Moreover, studying emotion and cognition in fish species broadens our scientific understanding of how emotion and cognition are represented in the central nervous system and what kind of role they play in the organization of behavior. For instance, on a macro neuro-architecture level the brains of fish species look dramatically different from those of mammals, while such a dramatic difference does not (always) occur at the level of emotion- and cognition-related behavior. Here, therefore, we discuss the evidence of emotion and cognition in fish species related to underlying neuro-architecture and the role that emotion and cognition play in the organization of behavior. To do so we use a framework encompassing a number of steps allowing a systematic approach to these issues. Emotion and cognition confer on human and non-human animals the capacity to compliment and/or override immediate reflexes to stimuli and so allow a large degree of flexibility in behavior. Systematic research on behavior that in mammals is indicative of emotion and cognition has been conducted in only a few fish species. The data thus far indicate that in these species brain-behavior relationships are not fundamentally different from those observed in mammals. Furthermore, data from other studies show evidence that behavior patterns related to emotion and cognition vary between fish species as well within fish species, related to sex and life history stage for example. From a welfare perspective, knowledge of such variability will potentially help us to design optimal living conditions for fish species kept by humans. 相似文献
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Ecological conservation monitoring programmes abound at various organisational and spatial levels from species to ecosystem. Many of them suffer, however, from the lack of details of goal and hypothesis formulation, survey design, data quality and statistical power at the start. As a result, most programmes are likely to fail to reach the necessary standard of being capable of rejecting a false null hypothesis with reasonable power. Results from inadequate monitoring are misleading for their information quality and are dangerous because they create the illusion that something useful has been done. We propose that conservation agencies and those funding monitoring work should require the demonstration of adequate power at the outset of any new monitoring scheme. 相似文献
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Oscar Horta 《Journal of Agricultural and Environmental Ethics》2010,23(3):243-266
In spite of the considerable literature nowadays existing on the issue of the moral exclusion of nonhuman animals, there is
still work to be done concerning the characterization of the conceptual framework with which this question can be appraised.
This paper intends to tackle this task. It starts by defining speciesism as the unjustified disadvantageous consideration
or treatment of those who are not classified as belonging to a certain species. It then clarifies some common misunderstandings
concerning what this means. Next, it rejects the idea that there are different kinds of speciesism. Such an idea may result
from confusion because there are (1) different ways in which speciesism can be defended; and (2) different speciesist positions,
that is, different positions that assume speciesism among their premises. Depending on whether or not these views assume other
criteria for moral consideration apart from speciesism, they can be combined or simple speciesist positions. But speciesism
remains in all cases the same idea. Finally, the paper examines the concept of anthropocentrism, the disadvantageous treatment
or consideration of those who are not members of the human species. This notion must be conceptually distinguished from speciesism
and from misothery (aversion to nonhuman animals). Anthropocentrism is shown to be refuted because it either commits a petitio principia fallacy or it falls prey to two arguments: the argument from species overlap (widely but misleadingly known as “argument
from marginal cases”) and the argument from relevance. This rebuttal identifies anthropocentrism as a speciesist view. 相似文献