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311.
Veronika Dornburg Gregg Marland 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):211-217
Kirschbaum (Mitig Adapt Strat Glob Change 11:1151–1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary
storage of carbon in the terrestrial biosphere “achieves effectively no climate-change mitigation”. His strongly worded statement
begs for a response. This paper argues that Kirschbaum’s conclusion is an artifact of the specific perspective of his analysis
and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change,
a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better
and longer is better, but even known temporary sinks have value.
相似文献
Gregg Marland (Corresponding author)Email: |
312.
G. J. Nabuurs I. J. J. van den Wyngaert W. Daamen H. Kramer P. Kuikman 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):267-282
A full account for carbon dioxide (CO2) and other greenhouse gas balance is presented for the Dutch forest and nature areas for 1990–2002 at a Tier 2.5 level. The
paper outlines how complex guidelines can be turned into a practical system, appropriate for a small country, making use of
the best knowledge and data available. The net total sink of all processes of the forest and other nature terrains balance
is very stable through time around an average of 1.74 million tonnes of CO2 per year. The sink is to a large extent determined by the growth of forest remaining forest, and the harvest taking place
in there. Newly added processes in this new National System are significant as well, but they compensate each other. The sources
from deforestation and nitrous oxide (N2O) emissions (around 900 ktonne CO2) are for two thirds compensated by the sinks from afforestation, dead wood, soil C changes due to land use changes, and trees
outside the forest. The land use changes between 1990 and 2000 showed that The Netherlands has an annual deforestation of
2504 ha (0.7% of the forest area) and an afforestation of 3124 ha. Deforestation led in total over the 13 years of 1990–2002
to an emission of 11.2 million tonne CO2 compensated by only 1.9 million tonne CO2 due to afforestation.
相似文献
G. J. NabuursEmail: |
313.
The structure of gallery networks in the nests of termite <Emphasis Type="Italic">Cubitermes</Emphasis> spp. revealed by X-ray tomography 总被引:1,自引:0,他引:1
Perna A Jost C Couturier E Valverde S Douady S Theraulaz G 《Die Naturwissenschaften》2008,95(9):877-884
Recent studies have introduced computer tomography (CT) as a tool for the visualisation and characterisation of insect architectures. Here, we use CT to map the three-dimensional networks of galleries inside Cubitermes nests in order to analyse them with tools from graph theory. The structure of these networks indicates that connections inside the nest are rearranged during the whole nest life. The functional analysis reveals that the final network topology represents an excellent compromise between efficient connectivity inside the nest and defence against attacking predators. We further discuss and illustrate the usefulness of CT to disentangle environmental and specific influences on nest architecture. 相似文献
314.
Natural chemical weathering of silicate rocks is a significant sink for soil and atmospheric CO2. Previous work suggested that natural chemical weathering may be stimulated by applying finely ground silicate rocks to agricultural
areas or forests [stimulated weathering (SW)]. However, it remained unknown if this technique is practical to sequester globally
significant amounts of CO2 under realistic conditions. Applying first estimates of “normal treatment” amounts from a literature review, we report here
a theoretical global maximum potential of 65 106 t sequestered C a−1 if SW would be applied homogenously on all agricultural and forested areas of the world. This is equivalent to 0.9% of anthropogenic
CO2 emissions (reference period 2000–2005). First, however, the assumed application of SW on most of the considered areas is
not economically feasible because of logistic issues, and second the net-CO2 sequestration is expected to amount to only a fraction of consumed CO2 due to the energy demand of the application itself (currently ~11%). Unless progress in application procedures is provided,
the recent realistic maximum net-CO2-consumption potential is expected to be much smaller than 0.1% of anthropogenic emissions, and the SW would thus not be one
of the key techniques to reduce atmospheric CO2 concentration. However, literature suggests that for some agricultural areas (croplands) and specifically for rice production
areas in humid climates, this SW may be a feasible tool to support international efforts to sequester CO2. SW may be cost effective for those areas if linked to the CO2-emission certificate trade in the future, and increases in crop production are taken into account. 相似文献
315.
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317.
为弥补事故分析法在道路危险品运输事故致因研究方面的缺失,解决传统事故分析方法分析结果不全面、防控措施不具体且针对性较差的问题,引入半定量功能共振事故模型(FRAM),通过定量化功能上下游耦合变异性,阐述事故发生机理同时,找到系统关键功能和关键链路,制定防控措施重点监控。结果表明:基于半定量的FRAM道路危险品运输事故分析方法能够更快、更准确地找出事故发生的关键功能和关键链路,制定针对性防控措施,有效提高道路危险品运输系统安全性。研究结果可为道路事故分析提供参考。 相似文献
318.
Dampwood termites, Zootermopsis angusticollis (Isoptera: Termopsidae), mount an immune response to resist microbial infection. Here we report on results of a novel analysis that allowed us to electrophoretically assess changes in hemolymph proteins in the same individual before and after exposure to a pathogen. We demonstrate that contact with a sublethal concentration of the entomopathogenic fungus Metarhizium anisopliae (Deuteromycotina:Hypomycetes) induces the production of protective proteins in nymphs, pseudergates (false workers), and soldiers. Termites exposed to an immunizing dosage of fungal conidia consistently showed an enhancement of constitutive proteins (62–85 kDa) in the hemolymph as well as an induction of novel proteins (28–48 kDa) relative to preimmunization levels. No significant differences in protein banding patterns relative to baseline levels in control and naïve termites were observed. Incubating excised and eluted induced proteins produced by immunized pseudergates or immunized soldiers with conidia significantly reduced the germination of the fungus. The fungistatic effect of eluted proteins differed significantly among five colonies examined. Our results show that the upregulation of protective proteins in the hemolymph underscores the in vivo immune response we previously recorded in Z. angusticollis. 相似文献
319.
文章建立了一种测定环境水体中8种酸性除草剂残留量的分析方法。1 000 mL样品在pH<2的情况下由乙醚分三次萃取后,萃取液经脱水,K-D浓缩至约1 mL,转移到衍生瓶中。在衍生瓶中补加2 mL正己烷、1 mL甲醇、8滴浓硫酸,80℃水浴加热1 h,进行甲醇衍生化处理,衍生后的样品运用气相色谱-质谱联用-分段选择离子扫描技术测定,内标法定量。结果表明:8种除草剂在0.05~2.5μg/L范围内线性均良好;方法灵敏度高,检出限均低于或等于0.02μg/L;方法的准确度和精密度高,在0.10、0.50、1.00、1.50μg/L添加水平下所有除草剂的回收率均在82.07%~116.99%之间,相对标准偏差RSD≤7.68%;经实际样品检测,可用于测定环境水体中酸性类除草剂的残留量。 相似文献
320.