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811.
U. Martin Persson Christian Azar 《Mitigation and Adaptation Strategies for Global Change》2007,12(7):1277-1304
The possibility of adopting national targets for carbon dioxide (CO2) emissions from tropical deforestation in a future international climate treaty has received increasing attention recently.
This attention has been prompted by proposals to this end and more intensified talks on possible commitments for developing
countries beyond the United Nations Framework Convention on Climate Change Kyoto Protocol. We analyze four main scientific
and political challenges associated with national targets for emissions from tropical deforestation: (1) reducing the uncertainties
in emission inventories, (2) preserving the environmental integrity of the treaty, (3) promoting political acceptance and
participation in the regime, and (4) providing economic incentives for reduced deforestation. We draw the following conclusions.
(1) Although there are large uncertainties in carbon flux from deforestation, these are in the same range as for other emissions
included in the current Kyoto protocol (i.e., non-CO2 GHGs), and they can be reduced. However, for forest degradation processes the uncertainties are larger. A large challenge
lies in building competence and institutions for monitoring the full spectrum of land use changes in developing countries.
(2 and 3) Setting targets for deforestation is difficult, and uncertainties in future emissions imply a risk of creating ‘tropical
hot air’. However, there are proposals that may sufficiently deal with this, and these proposals may also have the advantage
of making the targets more attractive, politically speaking. Moreover, we conclude that while a full carbon accounting system
will likely be politically unacceptable for tropical countries, the current carbon accounting system should be broadened to
include forest degradation in order to safeguard environmental integrity. (4) Doubts can be cast over the possible effect
a climate regime alone will have on deforestation rates, though little thorough analysis of this issue has been made.
相似文献
U. Martin PerssonEmail: |
812.
对海底管线穿孔后如何阻止溢油、减少海上.油污染,提出了采用负压保护的可行性方案. 相似文献
813.
814.
通过单因素试验研究了新型烟气净化装置(LAPD)运行参数变化对除尘效率的影响,结果表明:LAPD的除尘效率随着溢流口液面高度的增大而提高;随着环形管高度的增大而先提高后下降。通过正交试验,建立了LAPD的最佳工况参数标准。 相似文献
815.
简要介绍了济南分公司油气回收装置、真空泵的工作原理以及安装与调试应注意的问题. 相似文献
816.
统计了洛阳分公司2006年度事故隐患情况,从未遂事件、事故隐患的时间段、后果、性质、直接原因等方面进行了深入细致的分析,找出影响洛阳分公司安全生产的主要隐患,提出了相应对策措施和建议. 相似文献
817.
论述了输油泵站控制系统及微波通信系统遭受雷击的危害及原因,有针对性地采取了各种防雷的有效措施,完善微波通讯和站控及网络防雷保护系统,为确保输油安全生产提供了有利保证. 相似文献
818.
When encountering an already parasitized host, a parasitoid’s optimal choices (superparasitism, host rejection, host feeding
or infanticide) seem to depend on the individual species’ life history, because the same choice may have different fitness
consequences. We demonstrate infanticide under laboratory conditions by a polysphinctine, Zatypota albicoxa, which is a solitary koinobiont ectoparasitoid of spiders. The female always removed any previously attached egg or larva
from the body of the host spider, Parasteatoda tepidariorum, with a rubbing behaviour. She rubbed her ovipositor back and forth toward the undersurface of the attached egg or of the
saddle under the attached larva to pry it off and laid an egg after removal. When removing a larva, the infanticidal female
engaged exclusively in unfastening the ‘saddle’ which fastens the larva to the body of the spider. All larvae were removed
with the ‘saddle’ attached to the ventral surface of the body. The female invested more time to remove the medium second and
the large penultimate instar larvae than to remove eggs and first instar larvae because of the labour involved in unfastening
the saddle. Oviposition with infanticide of the medium second and the penultimate instar larvae imposed more time upon the
female than that on an unparasitized host. Removal of any previous occupant in spite of the associated labour costs suggests
that infanticide will always be adaptive, no matter the time costs to Z. albicoxa, because so much is invested in attacking the host and because the parasitoid cannot detect whether the spider is already
parasitized until she achieves subjugation. 相似文献
819.
Communication is shaped and constrained by the signaling environment. In aquatic habitats, turbidity can reduce both the quantity
and quality of ambient light and has been implicated in the breakdown of visual signaling. Here, we examined the relationship
between turbidity (quantified with long-term data) and the expression of carotenoid-based nuptial coloration in the red shiner
(Cyprinella lutrensis), a small-bodied cyprinid. Males in more turbid habitats displayed redder fins, and an experimental manipulation of adult
diet suggested that carotenoid intake alone did not explain among-population color differences. These results run counter
to similar studies where signal expression decreased in turbid conditions, and may be explained by the non-territorial red
shiner mating system, interactions between the mechanism of coloration and the signaling environment, or reduced cost of color
expression in turbid habitats (e.g., reduced predation risk). Our results highlight how the behavioral and ecological contexts
in which signals function can shape evolutionary responses to the environment. 相似文献
820.
A new mass estimate for the dodo (Raphus cucullatus), based on the lengths of the femur, tibiotarsus and tarsometatarsus, is attempted. The obtained mean mass is 10.2 kg, which
is less than previous estimates based on other methods, which ranged from 10.6 to 21.1 kg, and much lower than the 50 lbs
reported by a seventeenth-century eyewitness. The new estimated mass, which is similar to that of a large wild turkey, seems
more realistic than previous ones and supports the hypothesis that contemporary illustrations of extremely fat dodos were
either exaggerations, or based on overfed specimens. Pictures of “fat” dodos may also have been based on individuals exhibiting
a display behaviour with puffed out feathers. 相似文献