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31.
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再论可持续性科学: 新形势与新机遇   总被引:3,自引:0,他引:3  
近10年来,可持续性科学蓬勃发展,已成为21世纪全球普遍关注的一个重要的新科学领域.然而,在大力提倡可持续发展和生态文明建设的中国,可持续性科学尚未引起科学家和实践者的足够重视.为促进可持续性科学在中国的发展,2014年邬建国等曾撰文介绍什么是可持续性科学.本文进一步探讨了这一问题,并补充阐述了可持续性科学与可持续发展研究的关系、可持续性科学的科学范式及其8个基本论题.基于对可持续性科学发展动态的分析,作者认为,一方面,可持续性科学已进入系统推进的成熟发展期;另一方面,虽然我国可持续发展研究、实践与教育的热情高涨,但在可持续性科学领域起步较晚,落后于主要发达国家和南非.为此,本文在文献综述的基础上,提出促进中国发展可持续性科学的“三位一体”策略:一是“请进来”以服务中国实践;二是“走出去”以贡献中国智慧;三是“中西医结合”以引领学科发展.  相似文献   
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Although Myanmar exports millions of dollars of rattan cane each year, the last systematic treatment of rattans in this country was done over 100 years ago, and virtually nothing has been written about the collection and trade of this important forest resource. Here we report the results from a study of rattans in the Hukaung Valley Tiger Reserve in northern Myanmar. A total of 15 species of rattan were encountered; seven species are new records for Myanmar and two species are new to science. Inventory transects revealed that the density of commercial rattans in local forests averages 40.5 canes ≽4m long/hectare. Populations of all species appear to be actively regenerating. The current pattern of rattan exploitation, however, is largely uncontrolled and will eventually lead to resource depletion unless some form of management is implemented.  相似文献   
35.
Presently, agriculture worldwide is facing the major challenge of feeding the increasing population sustainably. The conventional practices have not only failed to meet the projected needs, but also led to tremendous environmental consequences. Hence, to ensure a food-secure and environmentally sound future, the major thrust is on sustainable alternatives. Due to challenges associated with conventional means of application of biocontrol agents in the management of biotic stresses in agroecosystems, significant transformations in this context are needed. The crucial role played by soil microbiome in efficiently and sustainably managing the agricultural production has unfolded a newer approach of rhizosphere engineering that shows immense promise in mitigating biotic stresses in an eco-friendly manner. The strategy of generating synthetic microbial communities (SynComs), by integrating omics approaches with traditional techniques of enumeration and in-depth analysis of plant–microbe interactions, is encouraging. The review discusses the significance of the rhizospheric microbiome in plant's fitness, and its manipulation for enhancing plant attributes. The focus of the review is to critically analyse the potential tools for the design and utilization of SynComs as a sustainable approach for rhizosphere engineering to ameliorate biotic stresses in plants. Furthermore, based on the synthesis of reports in the area, we have put forth possible solutions to some of the critical issues that impair the large-scale application of SynComs in agriculture.  相似文献   
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Symbiotic bacteria in herbivorous insects can have strong beneficial impacts on their host's survival, including conferring resistance to natural enemies such as parasitoid wasps or pathogens, while also imposing energetic costs on the host, resulting in cost‐benefit trade‐offs. Whether these trade‐offs favour the hosting of symbionts depends on the growth environment of the herbivore. Long‐term experimental grassland studies have shown that increasing plant species richness leads to an increased diversity of associated herbivores and their natural enemies. Such a change in natural enemy diversity, related to changes in plant diversity, could also drive changes in the community of symbionts hosted by the herbivorous insects. Aphids are one model system for studying symbionts in insects, and effects of host‐plant species and diversity on aphid‐symbiont interactions have been documented. Yet, we still understand little of the mechanisms underlying such effects. We review the current state of knowledge of how biodiversity can impact aphid‐symbiont communities and the underlying drivers. Then, we discuss this in the framework of sustainable agriculture, where increased plant biodiversity, in the form of wildflower strips, is used to recruit natural enemies to crop fields for their pest control services. Although aphid symbionts have the potential to reduce biological control effectiveness through conferring protection for the host insect, we discuss how increasing plant and natural enemy biodiversity can mitigate these effects and identify future research opportunities. Understanding how to promote beneficial interactions in ecological systems can help in the development of more sustainable agricultural management strategies.  相似文献   
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工业生物技术是利用生化反应和生物体机能进行物质合成加工与能量转化利用的集成技术,正在支撑建立以可发酵糖、秸秆、二氧化碳等可再生资源为原料的化学品绿色高效制造新路线,有望实现工业制造方式的根本转变,是支撑经济社会可持续发展的重大战略技术,已成为世界各国科技和产业竞争的焦点。本文从工业生物技术深度融入和支撑生物经济发展的态势出发,系统分析了我国工业生物技术和生物产业发展的现状、短板问题,提出了未来建议重点发展的主要方向。  相似文献   
38.
城市生态规划的回顾与展望   总被引:20,自引:2,他引:18  
刘洁  吴仁海 《生态学杂志》2003,22(5):118-122
回顾了城市生态规划的发展情况,对其发展前景进行了展望。从19世纪末至今,从Howard的“田园城市”到MacHarg的土地利用生态规划方法,再到基于生态系统理论的城市生态对策规划,城市生态规划的理论和方法在实践中不断完善。全球城市化进程的加快带来了一系列的生态环境问题。城市生态规划作为实现城市可持续发展的途径之一,越来越受到人们的关注,为生态城市建设服务是城市生态规划的发展方向。  相似文献   
39.
1. Until the late 1960s, Euterpe edulis was the most important edible palm species in the Brazilian markets. Since then, overharvesting of natural stands and the limited scope of plantations have caused the industry to shift to the multistemmed E. oleracea from the Amazon river estuary.
2. As a result of the relocation of the industry, the structure of the palm harvesting industry has changed and illegal trade has continued to exploit the remaining natural stands of E. edulis .
3. It is suggested that, to avoid the total harvesting of E. edulis and to achieve sustainable management of the palm heart, it will be necessary to diversify the local economy, create incentives for small land owners to improve their management practices, while keeping their competitiveness against the illegal trade, create the incentive of new sources of palm hearts and create a 'green stamping' for management palms.
4. Transformation of the illegal structure of the palm heart industry is probably the only solution to avoid the total depletion of the wild stands of E. edulis .  相似文献   
40.
LCA aims to help direct decisions in an environmentally sustainable direction. It indicates the environmental effects of choices and evaluates these against this background. Approaches to evaluation in LCA differ substantially, related to the way of modelling environmental effects and to the way these effects are combined into an overall judgement on alternative options. Several approaches are now operational, which are linked to different paradigms in decision making. It is shown that the choice of paradigm is quite decisive on the outcome of the analysis. Also within similar paradigms, different methods now operational may lead to different outcomes. These latter differences may be alleviated more easily than those related to paradigmatic choices, as they are partly a matter of refinement, and they partly result from legitimate differences in subjective priorities. The more basic paradigmatic differences can hardly be bridged. The practical relevancy of the subject is proven by applying different operational methods to one case, showing widely differing outcomes. The paradigm behind evaluating environmental effects is either values based, directly or through policy decisions, or economics based, as individual preferences measured in the monetary terms of willingness-to-pay. Accordingly, the different methods are “policy-oriented” or “monetary”. It may be doubted if the differences between these can be overcome in standardisation.  相似文献   
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