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1.
The conservation and sustainable use of forests in the twenty-first century pose huge challenges for forest management and policy. Society demands that forests provide a wide range of ecosystem services, from timber products, raw materials and renewable energy to sociocultural amenities and habitats for nature conservation. Innovative management and policy approaches need to be developed to meet these often-conflicting demands in a context of environmental change of uncertain magnitude and scale. Genetic diversity is a key component of resilience and adaptability. Overall, forest tree populations are genetically very diverse, conferring them an enormous potential for genetic adaptation via the processes of gene flow and natural selection. Here, we review the main challenges facing our forests in the coming century and focus on how recent progress in genetics can contribute to the development of appropriate practical actions that forest managers and policy makers can adopt to promote forest resilience to climate change. Emerging knowledge will inform and clarify current controversies relating to the choice of appropriate genetic resources for planting, the effect of silvicultural systems and stand tending on adaptive potential and the best ways to harness genetic diversity in breeding and conservation programs. Gaps in our knowledge remain, and we identify where additional information is needed (e.g., the adaptive value of peripheral populations or the genetic determinism of key adaptive traits) and the types of studies that are required to provide this key understanding.  相似文献   

2.
Environmental protection policies in the automobile market were not implemented until the motorisation of the masses in the 1960s caused an increasing environmental burden. The rising air pollution was considered a latent danger to humans, animals and plants. In the years up to 1985 the EU passed several regulations to limit the mass pollutants CO, CxHy and NOx. Germany was the first EU-member nation to also be concerned with lead in gasoline, passing reduction regulations as early as 1971. In 1986, several EU-member nations implemented the supply of unleaded gasoline. This decision was predominantly based on information about widespread forest damage. The reduction of lead emissions due to these regulations could be verified in different environmental systems. An example of this was the decline of atmospheric lead concentrations and human blood lead levels in Germany. With regard to industries, the German mineral oil and automobile markets were affected mostly. The price trend of gasoline was no longer only influenced by varying crude oil prices but also by tax discrimination between leaded and unleaded fuel. With regard to the distribution system, the market positions particularly of the medium-sized traders and the independent importers were weakened. In the automobile market, favourable terms of competition were experienced by producers who had already gained experience with catalyst systems in the US market. The Gasoline Lead Content Regulations had no significant effects on further economic indicators, except for competition. Electronic Publication  相似文献   

3.
The contribution of scientific knowledge and innovation to sustainability is demonstrated. Theory, discoveries, programmes and activities in both the natural as well as social sciences fields have greatly helped with the environmental, economic and social challenges of the past and current centuries, especially in the past 50 years or so. Nowadays, we increasingly realize the intimate link between science and society, and the need not only for science to inform policy but also to address requests by governments and the multiple stakeholders confronted with the challenge to achieve sustainable development. Current barriers to how science is conceived and related education is delivered hamper true interdisciplinarity, and the emerging field of sustainability science attempts inter alia to clarify how ‘a new generation of science’ can be designed so as to promote more integrated thinking to tackle complex societal issues. At the international level, and more specifically in the context of the United Nations, the practice of science has always entailed the need to solve problems such as climate change, ozone depletion, disaster risk, lack of food security, biodiversity loss, social instability and ineffective governance—to cite a few. In this regard, science in an intergovernmental context is by definition science that has to assist with the struggle for sustainability. Yet, a higher level of integration and cross-fertilization among disciplines as well as of participation among concerned stakeholders in the design and implementation of science-based programmes and activities carried out by the United Nations (and, in this article, the specific case of its Educational, Scientific and Cultural Organization—UNESCO—is presented) seems to be needed. The debate on sustainability science carried out in the academic circle and the experience of UNESCO in this area can be mutually supportive in further elucidating how, practically, the approach of sustainability science can enhance the achievement of sustainable development at multiple scales.  相似文献   

4.
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