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991.
Sustainable development and sustainable forestry: analogies,differences, and the role of flexibility 总被引:1,自引:1,他引:1
Various approaches have been developed to achieve sustainability in forestry, under changing social needs and, consequently,
changing definitions of sustainability. This has led to the confusing situation in which various groups have different understandings
of the meaning of ‘sustainability’. Likewise, the concepts utilized to achieve sustainability, often with a poorly defined
objective, are sometimes not clear and/or inconsistent as a systematic overview regarding definitions and concepts is lacking.
Based on a literature review, this paper discusses related terms such as sustainability, sustained yield management, sustainable
forestry, sustainable forest management and sustainable development: their history, concepts and relationships, from a European
perspective. Finally, flexibility is proposed as a solution to overcome the identified shortcomings at all scales, while focussing
on the enterprise level. The origin of the sustainability concept in forestry was first driven by forest experts, while participatory
elements have been considered since the more recent idea of sustainable development. Since then, much effort has been made
to achieve intragenerational fairness by creating an improved participatory process. Concurrently, the original idea of sustainable
forestry as long-term and future-oriented management, considering future generations’ needs fell behind. An increasing standing
timber volume in Europe and the discussion on climate change brought new interest in how to cope with risks in the context
of pervasive future uncertainties within the scope of promoting sustainable development. Although the consideration of risk
has been concentrated on as a topic in forest science in recent years, studies have mainly focused on the enhancement of forest
resistance against disturbances. However, precaution and risk avoidance alone are probably insufficient to achieve an improved
sustainable development that focuses on intergenerational fairness, as these more defensive approaches may disregard important
management opportunities involved with an uncertain future. A perhaps more promising approach, the idea of future options
and the ability to respond to changing social and biophysical circumstances (i.e. flexibility) as criteria for sustainable
development have only shown a shadowy existence up to now. To further develop the consistency of sustainability concepts,
a shift of sustainability approaches from continuity towards flexibility options is proposed. 相似文献
992.
2008年以来, 作为我国林业部门"引进来"国际合作战略的新举措, 欧洲投资银行项目开始在内蒙古、江西等省准备和实施。与世界银行等其他主要国际金融组织相比, EIB项目在中国, 尤其是林业部门仍处在探索阶段, 但潜力很大。文中概述EIB项目的背景及其在林业、应对气候变化方面的政策和评估要求, 提出我国林业应用欧洲投资银行贷款项目的对策建议。 相似文献
993.
研究了3个系列D-A结构化合物在5种不同极性溶剂中的荧光发射光谱及紫外吸收光谱,探讨了化合物的溶致变色规律,结果表明:3个系列化合物在不同极性溶剂中的荧光发射波长发生明显位移,在甲醇中发射波长最大,在环己烷中最小,但在二氧六环、四氢呋喃、二氯甲烷中,随着溶剂极性逐渐减小,发射波长发生红移;在不同极性溶剂中的荧光强度也各不相同,其中,在环己烷中最大,在甲醇中最小。化合物的紫外吸收波长受溶剂极性的影响,均在甲醇中有最小吸收波长,在不同极性溶剂中化合物的吸光度也不相同,在甲醇及环己烷中的吸光度较大。3个系列化合物均具备作为荧光分子探针探测外部环境极性大小的潜能。 相似文献
994.
目的 研究‘香妃’成花过程中主要内源物质的变化特点,为人工调控花期提供理论依据。 方法 选取了非诱导光周期下营养生长期(S1)以及诱导光周期下未分化期(S2)、总苞原基分化期(S3)、花序原基分化期(S4)、小花原基分化期(S5)5个时期的顶芽,分别测定可溶性糖、可溶性蛋白、生长素(IAA)、玉米素(ZT)、脱落酸(ABA)、赤霉素(GA3)的含量,并且以非诱导光周期为对照,分析诱导光周期下各种内源物质在成花过程中的作用。 结果 GA3因含量极低,在5个时期中都未能检测出;可溶性糖、ZT的含量以及可溶性糖/可溶性蛋白比值在非诱导光周期的营养生长期均达最高,并且随发育进程的推进逐渐降低;可溶性蛋白的含量在营养生长期处于中等水平,未分化期、花序原基分化期达最高,总苞原基分化期、小花原基分化期达最低;IAA含量在非诱导光周期的营养生长期达最高,虽在诱导光周期的花序原基分化期有所回升,但其水平仍低于营养生长期;ABA含量以及ABA/ZT在非诱导光周期的营养生长期达最低,随发育进程的推进持续升高,并在小花原基分化期降低;ABA/IAA随发育进程推进持续升高;ZT/IAA在总苞原基分花期之前急剧升高,之后,又急剧下降并维持在低于营养生长期的水平之下。 结论 相对于非诱导光周期,‘香妃’在诱导光周期下内源ABA、ABA/IAA、ABA/ZT维持在较高水平,以及可溶性糖、IAA、ZT、可溶性糖/可溶性蛋白维持在较低水平有利于成花;ZT/IAA维持在较高水平有利于成花的生理分化,而维持在较低水平则有利于成花的形态分化。 相似文献
995.
在酸性土壤中,铝对林木的毒害是限制林木生长、降低林木生产力、进而导致森林退化的主要因素之一。目前,国内外在林木铝毒害及耐铝机制方面已有较多的研究,但关于林木耐铝的生理和分子机制的综述性报道很少。文中综述了近年来林木对铝的富集、铝对林木生理和分子水平上的毒害等方面的研究进展,总结了林木耐铝的生理机制和分子机制,简要介绍了外源添加物对林木耐铝毒的调控机制,提出了今后有关林木铝毒需进一步研究的重点,以期为林木铝毒的深入研究提供参考以及为缓解我国酸性土壤林木铝毒害及森林的健康持续经营提供参考。 相似文献
996.
基于"3S"技术,采用总体蓄积抽样控制、小班调查、消耗量调查等方法,查清了师宗县各类土地面积和各类森林蓄积、林木和林地资源的种类、数量、质量,落实了森林分类经营区划,对调查数据动态变化进行了分析,提出了加强天然林保护、商品林多功能经营、发展林下经济和生态旅游等林业发展建议。 相似文献
997.
美国火炬松优良家系引种试验研究 总被引:6,自引:2,他引:6
从美国引入火炬松种子园自由授粉的33个优良家系进行引种试验。结果表明:家系间树高,胸径、单株材积生长量差异显著,经LSD比较选择,仅有6个家系单株材积生长量优于商品种;家系前-后期树高生长相关性显著;家系的遗传力大于单株的遗传力。结果还显示,引进经人工选择的优良家系,还需经过引种区测试,并注意选择最适种源区,方能用于育种与生产。 相似文献
998.
为解决现有人工冻结法施工后周围地层产生冻胀融沉所引发不良后果的问题,可设置加热限位管对冻土帷幕的发展进行限制,从而达到控制冻胀融沉的目的。本文运用有限元软件研究在冻土帷幕界面上设置加热限位管时对冻土帷幕温度场发展的影响规律,主要得出:加热限位管盐水温度每升高5℃,冻土帷幕厚度就减小约0.2 m;在已冻结30 d,冻土厚度发展到1.6 m冻土上,加热限位管循环5℃盐水时,随着时间的增加冻土厚度慢慢变小,加热限位管作用效果明显;在限位管开始循环热水前期,各点温度都有明显上升,离限位管越近温度所受影响越大;随着时间的推移,各点温度趋于稳定,循环热盐水温度越高,趋于稳定的温度值也越高。所得结果可为今后类似工程设计提供参考依据。 相似文献
999.
We investigated the correlation of large fires([300 ha) from 1992 to 2013 within the borders of the Antalya Regional Directorate of Forestry using the Keetch–Byram drought index(KBDI). Daily KBDI values were calculated for each year, and values for the period before the year 2000 differed significantly from those after2000. After 2000(large fires occurred in 2004, 2006, 2007,2008, 2010, and 2013), when KBDI values increased, the KBDI, but not the number of fires, was inversely correlated with the natural log of the burned area(NLBA). While there were both high and low KBDI values when the NLBA was small, only high KBDI values were associated with high NLBA values. Particularly for logarithmic values of 4 and higher, KBDI values increased in parallel with increases in NLBA values. On the basis of a Mann–Whitney U test done in addition to a Pearson correlation test, we found that when the burned areas were grouped according to small and large areas, the KBDI could be used to distinguish the two groups. Using a conditional probability analysis, we found that 4th, 5th and 6th class KBDI values may lead to large fires at the 60 % possibility.Similarly, the possibility of large fires greater than the median burned area in any given 6 years was found to be48 %. In addition, while the mean value of KBDI is 390.51 for the period from May to September for these 6 years, it is 359.93 for the other years. Consequently, the area burned also increased as the KBDI classes(Class 0: 0–99, Class 1:100–199, Class 2: 200–299, Class 3: 300–399, Class 4:400–499, Class 5: 500–599, Class 6: 600–699, and Class 7:700–800) increase. 相似文献
1000.
Umma Tamima 《林业研究》2016,27(4):853-861
The objective was to evaluate the performance of the co-management of Nishorgo Support Project at Chunati Wildlife Sanctuary in Bangladesh. I adopted the Focus Groups Discussion method for opinion survey and applied the SWOTAHP technique for data analysis. Local people did not participate in the decision-making process of forest management and they perceived co-management as a threat to their livelihoods. Moreover, mistrust and misunderstanding among different stakeholders, political and ethical conflicts, lack of property rights of tribal communities, and lack of accountability and transparency were identified as the drawbacks of co-management. 相似文献