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1.
P. R. Burbridge 《Hydrobiologia》1994,285(1-3):311-322
Freshwater habitats play a very important role in sustaining human activities. Natural functions of wetlands, and other freshwater habitats, generate a wide array of resources that directly or indirectly support the economic and social welfare of diverse groups of people. This role is being seriously weakened as a result of inappropriate planning and management approaches which fail to maintain the functional integrity of the freshwater ecosystems with the result that the flow and quality of resources is degraded. This paper illustrates some of the major functions of wetlands and presents a case for developing integrated planning and management practices that protect the health and productivity of freshwater wetlands and seek to optimise the sustainable use of the flows of resources they generate.  相似文献   
2.
Evidence suggests that the boundaries between rivers, floodplain wetlands, and adjacent upland communities are among the most important components of landscapes. In a landscape context, floodplain wetlands and their ecotones are important transition zones between uplands and aquatic ecosystems. Management of wetland patches and ecotones to achieve sustainable ecosystems requires action on a broad scale, giving consideration to all factors affecting wetlands and the drainage basins of which they are a part. In northeastern United States, a struggle to identify new sources of water has focussed attention on the sustainability of aquatic ecosystems.  相似文献   
3.
The contribution of agriculture to the sustainable development goals requires climate-smart and profitable farm innovations. Increasing the ammonia fertilizer applications to meet the global food demands results in high agricultural costs, environmental quality deterioration, and global warming, without a significant increase in crop yield. Here, we reported that a third microbial ammonia oxidation process, complete ammonia oxidation (comammox), is contributing to a significant ammonia fertilizer loss (41.9 ± 4.8%) at the rate of 3.53 ± 0.55 mg N kg−1 day−1 in agricultural soils around the world. The contribution of comammox to ammonia fertilizer loss, occurring mainly in surface agricultural soil profiles (0–0.2 m), was equivalent to that of bacterial ammonia oxidation (48.6 ± 4.5%); both processes were significantly more important than archaeal ammonia oxidation (9.5 ± 3.6%). In contrast, comammox produced less N2O (0.98 ± 0.44 μg N kg−1 day−1, 11.7 ± 3.1%), comparable to that produced by archaeal ammonia oxidation (16.4 ± 4.4%) but significantly lower than that of bacterial ammonia oxidation (72.0 ± 5.1%). The efficiency of ammonia conversion to N2O by comammox (0.02 ± 0.01%) was evidently lower than that of bacterial (0.24 ± 0.06%) and archaeal (0.16 ± 0.04%) ammonia oxidation. The comammox rate increased with increasing soil pH values, which is the only physicochemical characteristic that significantly influenced both comammox bacterial abundance and rates. Ammonia fertilizer loss, dominated by comammox and bacterial ammonia oxidation, was more intense in soils with pH >6.5 than in soils with pH <6.5. Our results revealed that comammox plays a vital role in ammonia fertilizer loss and sustainable development in agroecosystems that have been previously overlooked for a long term.  相似文献   
4.
SOS!濒临极限的生物多样性   总被引:6,自引:0,他引:6  
本文论述了生物多样性的价值、多样性丧失的严重性和后果,以及多样性保护与持续利用的对策。文中强调指出,生物界中的每片基因,每一个物种,每一类生态系统对人类的持久生存都是无价之宝,任何多样性的丧失都是不可逆、不可再生的,因而对人类的损失是难以估量的。然而目前由于人类剧烈的活动干扰如滥砍滥伐、滥捕滥猎、环境污染、火灾、垦荒等,生物多样性丧失的速率怵目惊心!若不赶快行动起来,人类赖以生存的生物多样性将所剩无几,人类生存的危机也将难以避免。从保护与利用及其协同发展出发,本文呼吁要大力开展生物多样性的研究和开发工作,目的一方面在于进一步加强生物多样性的基础调查和研究工作,另一方面在于使生物多样性资源更好地为人类造福。为减缓目前生物多样性所承受的压力及促进其恢复,本文建议对完全依赖野生生物资源的传统产业征收“资源更新税”;而对开发和利用生物多样性资源,不仅不影响野生资源,而且能替代它,或减缓其压力,或促进其恢复的高新技术产业,在税收上给予特别优惠。  相似文献   
5.
Long-lasting electronic products contribute to a sustainable society; however, both expected and actual lifetimes are in decline. This research provides in-depth insights into consumers’ considerations about product lifetimes, barriers to extending lifetimes, and responses to a product lifetime label. Results of interviews (n = 22) with Dutch consumers suggest a positive view on long-lasting products. Nevertheless, their products’ value depreciated during their lifetimes. Consumers consider themselves unable to estimate how long products should last, which can be detrimental as low expectations tend to negatively influence actual lifetimes. Also, use intensity and consumers’ care(less) behavior influence the lifetime. To extend product lifetimes, consumers often disregard the option of repairing malfunctioning products. They have limited knowledge and ability, and believe repair provides poor value for money. Lifetime extension can also be hindered by market-related factors, such as convenient replacement services, new technological developments, and (attractive) deals. We suggest a product lifetime label should contain relevant and reliable information; furthermore, we recommend including (extended) warranty information. When information about repairability is included, potential negative responses should be considered. Finally, raising awareness about the environmental impact of short-lived products via a label may have a positive effect but requires more research attention.  相似文献   
6.
Ethical discussions around ancient DNA (aDNA) research predate the technological breakthroughs that led to the accelerated generation of ancient genomic data, revealing a long-due need to address these aspects in the field. Given the diverse conflicts that genomics has raised towards the communities associated with the Non-living Human Ancestors under study, it has been suggested that the ethical and legal implications of genetically studying present-day and ancient human populations should be considered case-by-case. Nevertheless, the discussions have focused on US and European perspectives. To contribute from a local and Latin American position to the problem, we present the history of consensus and disagreement of the relationships between scientists and Indigenous communities of the Atlantic coast of the central Argentinian Patagonia. We describe how these relationships resulted in the approval of a groundbreaking provincial law that acknowledges the Indigenous community's right to be involved in decision-making concerning their Ancestors. In addition, we emphasize how these established relationships allowed the development of aDNA studies. With this background, we address the main ethical concerns of genomic studies of Ancestors identified in the reference literature and commit to applying some of the recommendations suggested in those ethical guidelines. Then, we reflect on possible negative consequences of ongoing research and propose some suggestions based on personal experiences that will contribute to moving the ethical field towards a more contextualized science with a local perspective.  相似文献   
7.
庐山野生观赏植物资源多样性及持续利用对策   总被引:8,自引:0,他引:8  
谢国文  季梦成  赖书绅   《广西植物》1996,16(3):259-264
庐山是我国著名的风景旅游和避暑胜地,也是我国中亚热带北缘植物多样性的宝库.本文在广泛调查、收集、整理的基础上,研究了庐山野生观赏植物资源多样性特征、分布、类型及其配置.本区分布有野生观赏植物528种,隶属于115科290属,其中乔木类138种,灌木类140种,藤木类52种,草本类198种.并根据开发与保护现状对庐山野生观赏植物资源多样性的持续利用提出了切实可行的对策.  相似文献   
8.
生态文明人类未来的文明关于人与自然持续发展的思考李建国(中国林业科学研究院林业研究所,北京100091)EcologicalCivilizationtheHumanFutureCivilizationConsiderationaboutHumanbe...  相似文献   
9.
Soil microbial diversity and the sustainability of agricultural soils   总被引:72,自引:1,他引:71  
Many world ecosystems are in various states of decline evidenced by erosion, low productivity, and poor water quality caused by forest clearing, intensive agricultural production, and continued use of land resources for purposes that are not sustainable. The biological diversity of these systems is being altered. Little research has been conducted to quantify the beneficial relationships between microbial diversity, soil and plant quality, and ecosystem sustainability. Ecosystem functioning is governed largely by soil microbial dynamics. Differences in microbial properties and activities of soils have been reported but are restricted to general ecological enumeration methods or activity levels, which are limited in their ability to describe a particular ecosystem. Microbial populations and their responses to stresses have been traditionally studied at the process level, in terms of total numbers of microorganisms, biomass, respiration rates, and enzyme activities, with little attention being paid to responses at the community or the organismal levels. These process level measurements, although critical to understanding the ecosystem, may be insensitive to community level changes due to the redundancy of these functions. As microbial communities comprise complex interactions between diverse organisms, they should be studied as such, and not as a black box into which inputs are entered and outputs are received at measured rates. Microbial communities and their processes need to be examined in relation to not only the individuals that comprise the community, but the effect of perturbations or environmental stresses on those communities.  相似文献   
10.
Today, the search for new energy sources continues unabated throughout the North. At the same time, scientists are increasingly concerned over the degradation of the Arctic and sub-Arctic environment stemming from fossil fuel and other large-scale energy projects already underway. Similar apprehensions are expressed by indigenous peoples who have often suffered from the impact of such development. While the most dramatic evidence of environmental devastation and social disruption is found in the Russian North, serious problems are by no means confined to that area alone. Nor are these negative effects necessarily limited to the borders of the country in which they originated. Indeed, the deleterious environmental impact of our global industrial economy has become sufficiently profound that social analysts are beginning to ask whether development strategies that cause such harm to the Arctic and sub-Arctic region should continue; and if not, what should replace them. This article addresses these issues as they relate to questions of sustainability, equity, political empowerment, and human rights in northwest Siberia and northern North America.  相似文献   
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