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581.
582.
本文从会计数字游戏产生的根源着手,分析了上市公司会计数字游戏滋生的内、外部条件及诱因,进而分析如何才能够减少会计数字游戏. 相似文献
583.
由早中元古代中深变质岩系组成的华南加里东海盆基底及东海、南海古陆。元古代晚期,海盆在拉张环境下继续沉降,于震旦、寒武、奥陶纪期间,沉积了厚近两万米的地槽型火山-砂泥质建造,陆源碎屑主要来自东海、南海古陆,直到中生代晚期古陆才裂陷成海,始成今日的海陆分布格局。 相似文献
584.
本文在对西昆仑山广布的岩浆岩尤其是花岗岩研究取得的成果基础上 ,结合区域构造、沉积建造等其它地质特征 ,再造了西昆仑山地质构造发展历程 ,进而研究了区内成矿堆积环境及其矿床地质特征。结果表明 ,西昆仑山经历了复杂的地质构造演化 ,是一条由北而南分别由加里东造山带、华力西造山带和燕山早期造山带组成的复合型造山带。区内存在以下 5种主要成矿堆积环境 :洋脊 (蛇绿岩 )成矿堆积环境 (塞浦路斯型含铜黄铁矿矿床 ,豆荚状铬、镍矿床 ) ,被动陆缘成矿堆积环境 (MVT铅锌矿床 ,Sedex型铅铜矿床 ) ,火山弧成矿堆积环境 (斑岩型铜矿床 ,黑矿型铜锌铅矿床 ,矽卡岩型铜铅锌多金属矿床 ) ,弧后盆地成矿堆积环境 (海底火山喷发沉积型铁铜金矿床 ,气液充填型铜金铁矿床 )和同碰撞成矿堆积环境 (伟晶岩型稀有金属矿床 ,伟晶岩型多金属银矿床 ) 相似文献
585.
IntroductionThenotionofsustainabledevelopmentwasproposedintheWorldConservationStrategy(IUCN,1980).Itispointedoutthattheconservationandthesustainabledevelopmentaremutuallydependentandtheyshouldbeintegrated,wheretheconservationmeansthemanagementofhuman… 相似文献
586.
A new environmental paradigm has emerged, reflecting a change in the public's understanding of resource sustainability. Forest
policy makers need to be better informed about such changes to achieve economic, social, and environmental objectives in a
manner that balances human needs and aspirations with ecosystem constraints. As an aid to this task, a forest resource accounting
system based on the key concept of natural capital could help reshape forest policies to provide an even wider spectrum of
benefits for both present and future generations by maintaining and enhancing the productive capacity of forest capital. Such
a resource accounting system would provide a tool for integrating multidimensional information requirements in measuring the
health of both forest ecosystems and economic systems. This paper outlines some of the features of this accounting system
and proposes and framework that would integrate economic and ecological characteristics of natural resources. Forest resource
accounting is urgently needed to achieve the sustainability goals of ecosystem management. 相似文献
587.
Ernest M. Thiessen Daniel P. Loucks 《Journal of the American Water Resources Association》1992,28(1):163-177
ABSTRACT: Since the early 1970s, a large volume of literature has accumulated related to multiobjective water resources management problems. A relatively small portion of this specifically addresses the negotiation process required when there are multiple decision makers with conflicting objectives. This paper focuses on that process and describes a computer program designed to assist such negotiation processes. This interactive computer assisted negotiation support system is called ICANS. ICANS is designed for dynamic, multi-issue, multi-party negotiation problems. Based on information provided in confidence by each party via an interactive graphical interface, the program can help determine if there exist any possible alternatives that are equivalent or even preferred to each party's decision in the absence of a negotiated agreement. If such alternatives exist, through a series of iterations in which each party's input data, assumptions, and preferences may change, ICANS can assist the parties in their search for a mutually acceptable and preferred agreement. A simple example illustrates the data requirements and the use of ICANS in negotiation experiments. 相似文献
588.
In this research we explored how the concepts and approaches of ecosystem services are currently used in water management in Europe, in the application of River Basin Management Plans (RBMP) developed for the EU Water Framework Directive (WFD). Five case studies have been considered, located in the River Basin Districts of the Po river (Italy), Scotland (United Kingdom), Scheldt river (Belgium), Danube river (Romania), Sado and Mira rivers and Ribeiras do Algarve (Portugal). These cases represent different regional contexts of application of this EU water policy, with specific socio-economic drivers and environmental issues. Each case study has developed an operational framework to analyse ecosystem services in practice together with a group of local stakeholders. In each regional case, we examined how EU water policy and RBMPs are implemented, considered legal and planning instruments from the national to the local scale, and we analysed the use of ecosystem service terms and concepts in the relevant planning instruments. In parallel, we explored the view of local stakeholders and water managers on the topic, collecting their opinion on three major aspects: the usefulness of the concepts and approaches of ecosystem services for WFD river basin management plans, the risks and benefits of their use, and the knowledge needs to put the concepts into practice. The major drawback of the ecosystem service approach seems to be the challenge for practitioners of understanding new concepts and methodologies, while the major advantages are that it highlights all the hidden benefits of a water body in good health and promotes multi-functionality and sustainability in water management. The results of this study provide a picture across Europe of the current use of the concepts of ecosystem services in the RBMP and relevant insight on the opinion of local stakeholders and water managers. 相似文献
589.
红色旅游在传承红色记忆方面发挥着重要作用,但对红色旅游为什么能够传承红色记忆,以及红色旅游传承红色记忆的具体过程等基础问题尚缺乏深入的理论探讨。以文化记忆理论和互动仪式链理论为依据,论证了红色记忆作为文化记忆、红色旅游作为仪式的理论合理性,明确了红色记忆传承的基本规律,提出了红色旅游传承红色记忆的理论逻辑和动态过程模型,并进一步讨论了红色旅游作为一种仪式在传承红色记忆方面的独特价值、作用边界、融合发展和实践路径等问题。研究结论有助于红色旅游理论研究者从更普适性的视角和更深的理论层次认识红色旅游与红色记忆之间的关系,为实践领域更好地开展红色旅游工作提供了基础理论支持。 相似文献
590.
中国粮食安全系统脆弱性评价及其驱动机制分析 总被引:4,自引:0,他引:4
从粮食安全系统的视角出发,运用VSD的脆弱性分析框架,从暴露性、敏感性、适应能力三个层面构建了中国粮食安全脆弱性评价指标体系,采用主成分分析方法对1991-2015年中国粮食安全脆弱性的暴露性、敏感性、适应能力进行定量分析,并探究了中国粮食安全脆弱性变化的总体趋势及其驱动因子。研究结果表明:(1)暴露性指数呈现出2阶段下降特征,年均下降0.121;敏感性指数呈现出快速上升和基本稳定的两阶段变化特征;适应能力指数则一直上升,年均提高0.117。(2)1991-2015年粮食安全系统脆弱性指数整体呈现下降趋势,表明中国粮食安水平有了明显提高;其变化过程可划分为1991-1999年、2000-2003年和2004-2015年三个阶段,第一、二阶段粮食安全水平的总体提高是基于“吃饱”水平上的提高,而第三阶段是基于“吃好”水平上的提高。(3)人均GDP、城镇化水平和城乡居民人均可支配收入四个因子共同驱动中国粮食安全脆弱性的变化,2000-2015年的第二阶段四因子对粮食安全脆弱性的驱动作用明显小于1991-1999的第一阶段,且第一驱动因子由第一阶段的农村居民人均可支配收入转变为第二阶段的人均GDP和城镇居民可支配收入。 相似文献