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41.
Fungi are undoubtedly important for ecosystem functioning; however, they have been omitted or given scant attention in most biodiversity policy documents, management plans, and formal conservation schedules throughout the world. This oversight may be due to a general lack of awareness in the scientific community and compounded by a scarcity of mycology‐associated curricula at the tertiary level and a lack of mycologists in research institutions. Although molecular techniques advance the systematic cataloging of fungi and facilitate insights into fungal communities, the scarcity of professional mycologists in the environmental sciences hampers conservation efforts. Conversely, citizen science initiatives are making significant contributions to the mycology discipline by increasing awareness and extending the scope of fungal surveys. Future research by professional and amateur mycologists into the distribution of fungi and their function in ecosystems will help identify wider and more effective conservation goals. 相似文献
42.
ABSTRACTRecent research has allowed us to quantify the costs and benefits of adopting renewable energy in specific municipalities, but how do these outcomes vary among communities at the national scale? This study uses survey responses from 47 Japanese municipalities to model these impacts and identifies key technological, social, and demographic factors that shape which communities benefit more from the renewable energy transition. On average, introducing renewable energy improves social equity, any financial burden on electricity prices is born most by wealthier residents, not the poor, and towns are predisposed to benefit from renewables no matter the amount introduced. To improve these impacts, towns can increase the amount of solar they host, or they can adjust the amount of CO2 emissions, PM emissions, tax revenue, jobs gained, or unpopular renewable power plants in their town. However, preferences and demographics matter as well. Age, education, and local preferences in favor of employment and community development all significantly relate to equity potential outcomes. Policymakers should consider adjusting their local energy priorities using these levers if they hope to engineer a renewable energy transition that is both positive and popular for their constituents. 相似文献
43.
44.
Changes in lipid content,lipid class composition and fatty acid composition of developing eggs and unfed larvae of cod (Gadus morhua) 总被引:1,自引:0,他引:1
Changes in the lipid class and fatty acid composition of developing eggs and unfed larvae of cod (Gadus morhua L.) were studied with the objective of determining probable requirements of cod larvae for dietary lipid. The eggs were collected on 24 March 1985 from holding tanks containing cod which had been caught off the northwest coast of Scotland. Phosphatidylcholine (PC) was the only lipid class to decline in absolute terms during embryogenesis. Catabolism of neutral lipid was initiated during the first week after hatching, and the rate of neutral lipid utilisation increased after the larvae had completely absorbed their yolk sacs. The quantity of triacylglycerol (TAG) remained constant during embryogenesis, but the percentage of 22:6(n-3) int TAG increased substantially during this period. It was calculated that ca. 33% of the 22:6(m-3) released during the process of PC catabolism was incorporated into TAG and sterol ester. The results suggest that PC, replete in appropriate essential fatty acids, should represent a major proportion of the lipid in artificial diets for fish and crustacean larvae. 相似文献
45.
F. S. Chapin III G. Peterson F. Berkes T. V. Callaghan P. Angelstam M. Apps C. Beier Y. Bergeron A.-S. Crèpin K. Danell T. Elmqvist C. Folke B. Forbes N. Fresco G. Juday J. Niemel A. Shvidenko G. Whiteman 《Ambio-人类环境杂志》2004,33(6):322-327
北极苔原带和北方森林(北部地区)因其分布广阔并远离农业土地利用变化及工业发展的影响,而一度被认为是地球上最后的净土.但如今这些地区如同地球上任何别的地区一样,也正经受着环境和社会变化的影响.本文总结了北部地区在全球系统中所起的作用,并提出方案以便对导致该地区对社会和环境变化敏感的那些因子进行评价. 相似文献
46.
Gunnar M·Sφrbφ 《Ambio-人类环境杂志》2003,32(2):113-117
引言 最近20年,以前许多关于非洲放牧生态系统的假设都已经被抛弃了[1~4].例如,过去一直被认为是稳定的系统,由于过度饲养和放牧而变得不再稳定了.因此,根据Hardn的著名"公共灾难"概念[5]提出了新的管理方案,并集中于改变土地使用体制与降低饲养数量相结合.但不幸的是,根据这种理念确定的放牧管理项目,几乎没有取得什么成功. 相似文献
47.
在环境承载力概念与理论的基础之上,从物种承载力的概念提出入手,探讨了物种承载力的定义、特征及其综合功能.并且从环境安全的角度切入,叙述了环境安全的提出和内涵;并主要从生物多样性、生态现代化理论等方面对物种承载力与环境安全的关系进行了分析和论述.物种承载力是对环境承载力从物种角度的深入研究和拓展,在研究环境安全方面提供一个新的角度. 相似文献
48.
M.D. Fraser V.J. Theobald J.B. Griffiths S.M. Morris J.M. Moorby 《Agriculture, ecosystems & environment》2009,129(1-3):182-192
In the UK the funding mechanism for moorland restoration is being implemented primarily through agri-environment schemes, yet to date remarkably few comparative grazing studies with domesticated livestock have been conducted on this type of vegetation community. In this experiment the diet composition of four groups of animals grazing heathland swards with low (8%) and high (61%) percentages of cover of Calluna vulgaris was estimated from faeces profiles of n-alkanes and long-chain fatty alcohols. Two breeds of sheep (Welsh Mountain (WM) and Scottish Blackface (SBF)), and two breeds of cattle (Welsh Black (WB) and Continental cross (CX)) grazed the experimental sites during two separate 14-day sampling sessions, in July and September respectively. Both species were selective feeders, consuming grasses (selectivity indices 0.20–1.0) in preference to dwarf shrubs (selectivity indices 0.20–1.0), but there were significant differences in the proportions of various plant groups within the diets. Although the sheep diets contained significantly more C. vulgaris, the quantities consumed were small (<10% of the diet), even on the High site, reflecting the biomass of the graminoid species present, and hence availability of preferred items. The SBF sheep were the only animal type to increase consumption of C. vulgaris later in the season. There were a number of significant differences in the composition of the diets selected by the two hill breeds of sheep used in the study, with the SBF sheep recorded as consuming more C. vulgaris. These results imply that through choice of breed land managers may be able to meet environmental goals more effectively without compromising returns from conventional production systems. In contrast, the overall diet composition of the two breed types of cattle was similar. This indicates that commercial breeds have the potential to deliver the types of environmental benefits associated with grazing of traditional breeds. 相似文献
49.
吐鲁番市历史文化遗址环境生态敏感性综合分析 总被引:1,自引:0,他引:1
针对历史文化资源保护的迫切需求利用高精度的地形数据和生态环境调查资料在GIS技术的支持下进行了历史文化遗址环境生态敏感性评价。以吐鲁番市区的历史文化遗址环境生态敏感性问题为研究对象选取高程等9个敏感性因子,利用层次分析法(AHP)确定敏感性因子权重结合GIS空间分析技术得到吐鲁番市区历史文化遗址环境生态敏感性结果。结果表明:吐鲁番市区历史文化遗址的生态敏感性总体较高,区域差异比较明显。国家级遗址和自治区级遗址都处在高度敏感状态,县市级遗址处在中度敏感状态,急需加强保护。最后提出分类保护措施为今后生态防范措施的针对性提供科学依据。 相似文献
50.
研究了中国北方某流域不同污染源的污染贡献,结果表明:COD贡献量点源为719.21 t,农业面源污染为7 488.02 t,农业面源污染是该流域水环境污染的主要来源.农业面源污染物等标污染负荷总量为8 359.44×106 m3/a.不同污染源污染贡献比例:农田化肥占49.24%、畜禽养殖占35.10%、农村生活占14.69%、农作物秸秆仅占0.97%.污染物贡献量比例.TN占56.46%、TP占39.06%、COD仅占4.48%. 相似文献