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931.
Enrico Cappellini M. Thomas P. Gilbert Filippo Geuna Girolamo Fiorentino Allan Hall Jane Thomas-Oates Peter D. Ashton David A. Ashford Paul Arthur Paula F. Campos Johan Kool Eske Willerslev Matthew J. Collins 《Die Naturwissenschaften》2010,97(2):205-217
We report here the first integrated investigation of both ancient DNA and proteins in archaeobotanical samples: medieval grape (Vitis vinifera L.) seeds, preserved by anoxic waterlogging, from an early medieval (seventh–eighth century A.D.) Byzantine rural settlement in the Salento area (Lecce, Italy) and a late (fourteenth–fifteenth century A.D.) medieval site in York (England). Pyrolysis gas chromatography mass spectrometry documented good carbohydrate preservation, whilst amino acid analysis revealed approximately 90% loss of the original protein content. In the York sample, mass spectrometry-based sequencing identified several degraded ancient peptides. Nuclear microsatellite locus (VVS2, VVMD5, VVMD7, ZAG62 and ZAG79) analysis permitted a tentative comparison of the genetic profiles of both the ancient samples with the modern varieties. The ability to recover microsatellite DNA has potential to improve biomolecular analysis on ancient grape seeds from archaeological contexts. Although the investigation of five microsatellite loci cannot assign the ancient samples to any geographic region or modern cultivar, the results allow speculation that the material from York was not grown locally, whilst the remains from Supersano could represent a trace of contacts with the eastern Mediterranean. 相似文献
932.
分段进水生物接触氧化工艺处理河道污水的试验研究 总被引:6,自引:1,他引:5
选择滇池入湖污染负荷最高的大清河为对象,以分段进水生物接触氧化(SFBC)工艺对河道污水开展了分流处理的试验研究,已完成冬季枯水期、春季枯水期及夏季丰水期3个时期的研究.结果表明.SFBC工艺对水质变化具有很好的适应性,调整各时期的运行参数,可以使COD及TP的去除率分别稳定在50%和40%左右,但TN的去除受水温及溶解氧等的影响很大,在逐渐稳定后去除率可达到20%左右.接种活性污泥可以加快装置的启动.但总体去除效果不及来水自然驯化的污泥.随着运行时间延长以及来水带入河道底泥的影响.有无接种污泥在处理效率上的差别逐渐消失. 相似文献
933.
Jay S. Gregg Steven J. Smith 《Mitigation and Adaptation Strategies for Global Change》2010,15(3):241-262
As co-products, agricultural and forestry residues represent a potential low cost, low carbon, source for bioenergy. A method
is developed for estimating the maximum sustainable amount of energy potentially available from agricultural and forestry
residues by converting crop production statistics into associated residue, while allocating some of this resource to remain
on the field to mitigate erosion and maintain soil nutrients. Currently, we estimate that the world produces residue biomass
that could be sustainably harvested and converted into nearly 50 EJ yr−1 of energy. The top three countries where this resource is estimated to be most abundant are currently net energy importers:
China, the United States (US), and India. The global potential from residue biomass is estimated to increase to approximately
50–100 EJ yr−1 by mid- to late- century, depending on physical assumptions such as of future crop yields and the amount of residue sustainably
harvestable. The future market for biomass residues was simulated using the Object-Oriented Energy, Climate, and Technology
Systems Mini Climate Assessment Model (ObjECTS MiniCAM). Utilization of residue biomass as an energy source is projected for the next century under different climate
policy scenarios. Total global use of residue biomass is estimated to be 20–100 EJ yr−1 by mid- to late- century, depending on the presence of a climate policy and the economics of harvesting, aggregating, and
transporting residue. Much of this potential is in developing regions of the world, including China, Latin America, Southeast
Asia, and India. 相似文献
934.
Mart-Jan Schelhaas Geerten Hengeveld Marco Moriondo Gert Jan Reinds Zbigniew W. Kundzewicz Herbert ter Maat Marco Bindi 《Mitigation and Adaptation Strategies for Global Change》2010,15(7):681-701
Risks can generally be described as the combination of hazard, exposure and vulnerability. Using this framework, we evaluated
the historical and future development of risk of fire and wind damage in European forestry at the national level. Fire risk
is expected to increase, mainly as a consequence of an increase in fire hazard, defined as the Fire Weather Index in summer.
Exposure, defined as forest area, is expected to increase slightly as a consequence of active afforestation and abandonment
of marginal agricultural areas. Adaptation options to fire risk should therefore aim to decrease the vulnerability, where
a change in tree species from conifers to broadleaves had most effect. Risk for wind damage in forests is expected to increase
mainly as a consequence of increase in exposure (total growing stock) and vulnerability (defined by age class and tree species
distribution). Projections of future wind climate indicate an increase in hazard (storminess) mainly over Western Europe.
Adaptation options should aim to limit the increase in exposure and vulnerability. Only an increase in harvest level can stop
the current build-up of growing stock, while at the same time it will lower vulnerability through the reduction of the share
of old and vulnerable stands. Changing species from conifers to broadleaves helps to reduce vulnerability as well. Lowering
vulnerability by decreasing the rotation length is only effective in combination with a high demand for wood. Due to data
limitations, no forecast of future fire area or damaged timber amount by storms was possible. 相似文献
935.
936.
Stefan Hochrainer Joanne Linnerooth-Bayer Reinhard Mechler 《Mitigation and Adaptation Strategies for Global Change》2010,15(7):797-810
This paper examines the legitimacy, viability and efficiency of the European Union Solidarity Fund by asking whether the Fund
meets its stated purpose of providing solidarity within the EU, whether it is sufficiently capitalized and if it promotes
disaster risk reduction in Europe. In examining these questions, we make use of ADAM models of disaster risks throughout Europe.
We conclude that the Solidarity Fund falls short on all three counts, and we suggest possible alternatives. Most far-reaching,
we explore whether the EUSF could support insurance systems in Europe by, among other possible activities, capitalizing national
public-private insurance programs and providing support for government risk transfer. This would leverage the Fund’s capital
and would overcome barriers to the provision of private and public sector insurance in uncertain catastrophe markets. It would
also make insurance more affordable to Europe’s most vulnerable communities. Finally, it would reduce the disincentives for
risk reduction inherent in post-disaster assistance. 相似文献
937.
利用AA3流动注射分析仪,同时对地表水中的挥发酚和氰化物进行测定,分析流程中使用了在线恒温蒸馏器。同传统的分析方法相比,本法分析测定数据准确、可靠、高效,大大缩短了测定时间,只需将两种标准配制成混合标样,一次取样完成两个项目的测定。回收率为90%~110%,相关系数达到0.9992以上。 相似文献
938.
939.
扬州市长江段不同水层中鱼类有机氯农药残留研究 总被引:1,自引:0,他引:1
鱼肉含有的蛋白质,脂肪,矿物质,维生素对人的健康起到重要的作用,因而被大多数人所青睐。由于有机氯农药具有较高的杀虫活性,曾被广泛使用。中国早已停产,但由于其性质稳定在自然界不易分解属于高残留农药,残留于植物中有机氯农药,可通过"食物链"或其他途径进入动物体内,鱼类也会受影响。本文根据淡水鱼在水中分布状况,选取了扬州市长江段生活在不同水层中三种鱼类为分析对象。选取容易富集有机氯农药的腹部肌肉为实验样品测定部位,采用加速溶剂萃取法前处理分析鱼肉中有机氯农药并对该分析方法进行完善,通过实验总结出能满足环境监测工作中对淡水河流中鱼类有机氯农药测定,并能及时掌握淡水鱼类中有机氯农药对人身健康状况的影响。 相似文献
940.