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431.
Jon Rosales 《Climatic change》2008,88(2):93-111
Environmental policy, including the Kyoto Protocol, is laden with values. Recognizing this fact can help UNFCCC parties come
to agreement. Much of the contention surrounding the post-Kyoto negotiations can be explained through a framework of values.
This article summarizes the arguments used by proponents and critics of emissions trading of greenhouse gas emissions under
the Kyoto Protocol through such a framework of values. Proponents and critics of emissions trading espouse common values,
such as achievement, to work toward ameliorating climate change; there is less agreement on emissions trading seen through
values such as responsibility and fairness. As non-Annex I parties are expected to take a more active role in the second commitment
period, identifying values held by those working on their behalf will facilitate negotiations and help develop a discourse
that is inclusive of their interests. Annex I parties can also benefit from the identification of the values to better convey
their interests. All parties can use the values framework identified here to construct a more durable climate change regime. 相似文献
432.
Carbon sequestration in Africa: The land tenure problem 总被引:3,自引:0,他引:3
The prospect of using tropical forest projects to sequester significant amounts of atmospheric carbon as one mitigation approach to climate change has received considerable attention. In the Kyoto Protocol, the Clean Development Mechanism (CDM) aspires to make such projects viable. This article examines the prospect of these projects in Africa, and argues that land tenure is much more than just a set of variables to be changed, and that instead it exists as a prohibitive obstacle to the implementation of afforestation and reforestation sequestration approaches. Five primary tenure problems are examined: (1) the disconnect between customary and statutory land rights, (2) legal pluralism, (3) tree planting as land claim, (4) expansion of treed areas in smallholder land use systems, and (5) the difficulty of using the ‘abandoned land’ category. The pervasiveness of these tenurial issues mean that the prospects for successfully implementing afforestation and reforestation projects in Africa are in reality quite weak. The current project approach to carbon storage in Africa needs to be significantly realigned with African reality in order for sequestration expectations to be practical. 相似文献
433.
Pricing China's irrigation water 总被引:1,自引:0,他引:1
Many development agencies and other actors are advocating that China adopt a system of water markets or of high water prices in order to resolve the inefficiencies of irrigation agriculture and to supply sufficient water for growing urban and industrial uses. We argue that this proposal rests on a series of propositions: that the price of water is too low to encourage farmers to be efficient; that farmers are not charged volumetric prices and so are not encouraged to conserve water; that water is scarce largely because farmers are profligate in their use of water; and that proper pricing of water will not affect equity. None of these contentions is true. Farmers have to pay not only the official charges for water but also the much higher costs of pumping it onto their fields. Once pumping is included, farmers are paying prices that are volumetric. Furthermore, the inefficiency of farmers arises in large part from the manner in which water is delivered to them: the system offers no rewards for care in the use of water and instead rewards greed. And, finally, although it might be true that higher prices do not affect equity within a village, in fact they would have substantial effects on inter-sectoral equity, with farmers becoming worse off in comparison to urban dwellers. The paper concludes by sketching a more appropriate scheme for raising the efficiency of use of irrigation water. 相似文献
434.
While extensively occurring natural resources play a fundamental role in the survival and recovery of postwar populations,
their management is not presently part of the operational priorities in a peace process. Dependence on naturally occurring
food, fuel, water, secure locations, and products that can be obtained and sold quickly for dislocated, war-weary populations
is a primary approach to postwar livelihoods. The peace process, however, focuses on the logistical and institutional aspects
of security, demobilization, reintegration and humanitarian efforts. The result is profound degradation of the spatially extensive
resources necessary for longer-term recovery. The primary reason for the inattention to resource degradation in a peace process
is that conventional conservation approaches do not fit with the priorities of a peace process or attend to the immediate
needs of a postwar population; designed as they are for stable, peaceful settings. This article focuses on the need to derive
postwar natural resource management approaches which can work with the in-place priorities of a peace process. Four such approaches
are suggested, with successful examples from specific countries.
相似文献
Jon UnruhEmail: |
435.
Michael K. Shepard Karelyn M. Kressler Maureen E. Ockert-Bell Ellen S. Howell Jon D. Giorgini Steven J. Ostro 《Icarus》2008,195(1):220-225
We observed the E-class main-belt Asteroids (MBAs) 44 Nysa and 434 Hungaria with Arecibo Observatory's S-band (12.6 cm) radar. Both asteroids exhibit polarization ratios higher than those measured for any other MBA: Nysa, μc=0.50±0.02 and Hungaria, μc=0.8±0.1. This is consistent with the high polarization ratios measured for every E-class near-Earth asteroid (NEA) observed by Benner et al. [Benner, L.A.M., and 10 collegues, 2008. Icarus, submitted for publication] and suggests a common cause. Our estimates of radar albedo are 0.19±0.06 for Nysa and 0.22±0.06 for Hungaria. These values are higher than those of most MBAs and, when combined with their high polarization ratios, suggest that the surface bulk density of both asteroids is high. We model Nysa as an ellipsoid of dimension 113×67×65 km (±15%) giving an effective diameter Deff=79±10 km, consistent with previous estimates. The echo waveforms are not consistent with a contact binary as suggested by Kaasalainen et al. [Kaasalainen, M., Torppa, J., Piironen, J., 2002. Astron. Astrophys. 383, L19-L22]. We place a constraint on Hungaria's maximum diameter, Dmax?11 km consistent with previous size estimates. 相似文献
436.
Jon M. Friedrich Robert J. Macke Douglas P. Wignarajah Mark L. Rivers Daniel T. Britt Denton S. Ebel 《Planetary and Space Science》2008,56(7):895-900
The extraordinarily uncompacted nature of the ordinary L chondrite fall Baszkówka gives a unique opportunity to investigate the potentially pre-compaction pore size distribution in an equilibrated ordinary chondrite. Using X-ray microtomography and helium pycnometry on two samples of Baszkówka, we have found that on average, two-thirds of the 19.0% porosity resides in inter- and intra-granular voids with volumes between 3×10−5 and 3 mm3. We show the cumulative number density of pore volumes observable by X-ray microtomography obeys a power law distribution function in this equilibrated ordinary chondrite. We foresee these data adding to our understanding of the impact processing of chondrites and their parent asteroids, where porosity and pore size play significant roles in the parameterization of impact events. 相似文献
437.
David A. Wake Ravi K. Sheth Robert C. Nichol Carlton M. Baugh Joss Bland-Hawthorn Matthew Colless Warrick J. Couch Scott M. Croom Roberto De Propris Michael J. Drinkwater Alastair C. Edge Jon Loveday Tsz Yan Lam Kevin A. Pimbblet Isaac G. Roseboom Nicholas P. Ross Donald P. Schneider Tom Shanks Robert G. Sharp 《Monthly notices of the Royal Astronomical Society》2008,387(3):1045-1062
438.
Robert Mikutta Klaus Kaiser Antje Vollmer Jon Chorover Georg Guggenberger 《Geochimica et cosmochimica acta》2010,74(7):2142-3154
Large portions of organic N (ON) in soil exist tightly associated with minerals. Mineral effects on the type of interactions, chemical composition, and stability of ON, however, are poorly understood. We investigated mineral-associated ON along a Hawaiian soil chronosequence (0.3-4100 kyr) formed in basaltic tephra under comparable climatic, topographic, and vegetation conditions. Mineral-organic associations were separated according to density (ρ > 1.6 g/cm3), characterized by X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge fine structure (NEXAFS) and analyzed for amino acid enantiomers and amino sugars. The 14C activity of mineral-bound OC was estimated by accelerator mass spectrometry. The close OC-ON relationship (r = 0.96) and XPS results suggest that ON exists incorporated in bulk mineral-bound OM and likely becomes associated with minerals as part of sorbing OM. The youngest site (0.3 kyr), with soils mainly composed of primary minerals (olivine, pyroxene, feldspar) and with little ON, contained the largest proportion of hydrolyzable amino sugars and amino acids but with a small share of acidic amino acids (aspartic acid, glutamic acid). In soils of the intermediate weathering stage (20-400 kyr), where poorly crystalline minerals and metal(hydroxide)-organic precipitates prevail, more mineral-associated ON was present, containing a smaller proportion of hydrolyzable amino sugars and amino acids due to the preferential accumulation of other OM components such as lignin-derived phenols. Acidic amino acids were more abundant, reflecting the strong association of acidic organic components with metal(hydroxide)-organic precipitates and variable-charge minerals. In the final weathering stage (1400-4100 kyr) with well-crystalline secondary Fe and Al (hydr)oxides and kaolin minerals, mineral-organic associations held less ON and were, relative to lignin phenols, depleted in hydrolyzable amino sugars and amino acids, particularly in acidic amino acids. XPS and NEXAFS analyses showed that the majority (59-78%) of the mineral-associated ON is peptide N while 18-34% was aromatic N. Amino sugar ratios and d-alanine suggest that mineral-associated ON comprises a significant portion of bacterial residues, particularly in the subsoil. With increasing 14C age, a larger portion of peptide N was non-hydrolyzable, suggesting the accumulation of refractory compounds with time. The constant d/l ratios of lysine in topsoils indicate fresh proteinous material, likely due to continuous sorption of or exchange with fresh N-containing compounds. The 14C and the d/l signature revealed a longer turnover of proteinous components strongly bound to minerals (not NaOH-NaF-extractable). This study provides evidence that interactions with minerals are important in the transformation and stabilization of soil ON. Mineral-associated ON in topsoils seems actively involved in the N cycling of the study ecosystems, accentuating N limitation at the 0.3-kyr site but increasing N availability at older sites. 相似文献
439.
Johan Rydberg Jon Karlsson Ida Wanhatalo Richard Bindler 《Geochimica et cosmochimica acta》2010,74(24):7116-7126
Even if mires have proven to be relatively reliable archives over the temporal trends in atmospheric mercury deposition, there are large discrepancies between sites regarding the magnitude of the anthropogenic contribution to the global mercury cycle. A number of studies have also revealed significant differences in mercury accumulation within the same mire area. This raises the question of which factors, other than mercury deposition, affect the sequestration of this element in peat. One such factor could be vegetation type, which has the potential to affect both interception and retention of mercury. In order to assess how small-scale differences in vegetation type can affect mercury sequestration we sampled peat and living plants along three transects on a northern Swedish mire. The mire has two distinctly different vegetation types, the central part consists of an open area dominated by Sphagnum whereas the surrounding fen, in addition to Sphagnum mosses, has an understory of ericaceous shrubs and a sparse pine cover. A few main patterns can be observed in our data; (1) Both peat and Sphagnum-mosses have higher mercury content (both concentration and inventory) in the pine-covered fen compared to the open Sphagnum area (100% and 71% higher for peat and plants, respectively). These differences clearly exceed the 33% difference observed for lead-210, which is considered as a good analogue for atmospheric mercury deposition. (2) The differences in mercury concentration between peat profiles within a single vegetation type can largely be attributed to differences in peat decomposition. (3) When growing side by side in the open Sphagnum area, the moss species Sphagnum subsecundum has significantly higher mercury concentrations compared to S. centrale (24 ± 3 and 18 ± 2 ng Hg g−1, respectively). Based on these observations we suggest that species composition, vegetation type and decomposition can affect the mercury sequestration in a peat record, and that any changes in these properties over time, or space, have the potential to modify the mercury deposition signal recorded in the peat. 相似文献
440.
Jon D. Woodhead 《Geostandards and Geoanalytical Research》2010,34(4):395-406
This review documents developments and applications in the field of isotope ratio determination, as reflected in the literature for the Earth and environmental sciences for the years 2008 and 2009. The emphasis is predominantly on applications, reflecting the enormous diversity of problems to which isotopic analysis can now be applied, but viewed in the context of rapid development of new analytical methodologies as significant new drivers of research output. 相似文献