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41.
K. Bassett 《地球表面变化过程与地形》1994,19(3):273-276
A number of comments are made as a response to the editorial “Real” geomorphology' (Richards, 1990). The call for more involvement by geomorphologists in current philosophical debate is welcomed and the adoption of a broadly realist scientific approach is supported. Some contentious issues arise from this debate and these are outlined and discussed. 相似文献
42.
This reply is in response to Burgess et al.’s Commentary on our original article, “The REDD Menace: Resurgent protectionism in Tanzania's mangrove forests.” Their commentary, we argue, shifts the focus from WWF's past conservation work and environmental narratives in the Rufiji Delta North, the subject of our article, to its current forest carbon inventory work. We do not comment on WWF's new work. Our principal concern remains on the environmental narratives crafted by WWF that were used to justify attempts to remove Warufiji small-scale rice farmers from the mangrove forests in the Rufiji Delta North. We emphasize the political implications of designating forest areas for carbon forestry and REDD projects in terms of forest dependent people's land and livelihood rights. We argue from environmental historical and social justice perspectives that the Warufiji should be counted among the winners, not the losers, in the green value chains currently under construction. 相似文献
43.
Reduced Emissions from Deforestation and Degradation (REDD+) is being proclaimed as “a new direction in forest conservation” (Anglesen, 2009: 125). This financial incentives-based climate change mitigation strategy proposed by the UNEP, World Bank, GEF and environmental NGOs seeks to integrate forests into carbon sequestration schemes. Its proponents view REDD+ as part of an adaptive strategy to counter the effects of global climate change. This paper combines the theoretical approaches of market environmentalism and environmental narratives to examine the politics of environmental knowledge that are redefining socio-nature relations in the Rufiji Delta, Tanzania to make mangrove forests amenable to markets. Through a case study of a “REDD-readiness” climate change mitigation and adaptation project, we demonstrate how a shift in resource control and management from local to global actors builds upon narratives of environmental change (forest loss) that have little factual basis in environmental histories. We argue that the proponents of REDD+ (Tanzanian state, aid donors, environmental NGOs) underestimate the agency of forest-reliant communities who have played a major role in the making of the delta landscape and who will certainly resist the injustices they are facing as a result of this shift from community-based resource management to fortress conservation. 相似文献
44.
Intercomparison of Boron Isotope and Concentration Measurements. Part II: Evaluation of Results 总被引:3,自引:1,他引:3
Roberto Gonfiantini Sonia Tonarini Manfred Grning Alessandra Adorni‐Braccesi Assad S. Al‐Ammar Marcus Astner Sebastien Bchler Ramon M. Barnes Randy L. Bassett Alain Cocherie Annette Deyhle Andrea Dini Giorgio Ferrara Jrme Gaillardet Judith Grimm Catherine Guerrot Urs Krhenbühl Graham Layne Damien Lemarchand Anette Meixner D. Jack Northington Maddalena Pennisi Eva Reitznerov Ilia Rodushkin Naoji Sugiura Regina Surberg Sabine Tonn Michael Wiedenbeck Samuel Wunderli Yingkai Xiao Thomas Zack 《Geostandards and Geoanalytical Research》2003,27(1):41-57
The Istituto di Geoscienze e Georisorse (IGG), on behalf and with the support of the International Atomic Energy Agency (IAEA), prepared eight geological materials (three natural waters and five rocks and minerals), intended for a blind interlaboratory comparison of measurements of boron isotopic composition and concentration. The materials were distributed to twenty seven laboratories - virtually all those performing geochemical boron isotope analyses in the world -which agreed to participate in the intercomparison exercise. Only fifteen laboratories, however, ultimately submitted the isotopic and/or concentration results they obtained on the intercomparison materials. The results demonstrate that interlaboratory reproducibility is not well reflected by the precision values reported by the individual laboratories and this observation holds true for both boron concentration and isotopic composition. The reasons for the discrepancies include fractionations due to the chemical matrix of materials, relative shift of the zero position on the δ11 B scale and a lack of well characterized materials for calibrating absolute boron content measurements. The intercomparison materials are now available at the IAEA (solid materials) and IGG (waters) for future distribution. 相似文献
45.
Aquifers in the arid alluvial basins of the southwestern U.S. are recharged predominantly by infiltration from streams and
playas within the basins and by water entering along the margins of the basins. The Tucson basin of southeastern Arizona is
such a basin. The Santa Catalina Mountains form the northern boundary of this basin and receive more than twice as much precipitation
(ca. 700 mm/year) as does the basin itself (ca. 300 mm/year). In this study environmental isotopes were employed to investigate
the migration of precipitation basinward through shallow joints and fractures. Water samples were obtained from springs and
runoff in the Santa Catalina Mountains and from wells in the foothills of the Santa Catalina Mountains. Stable isotopes (δD
and δ18O) and thermonuclear-bomb-produced tritium enabled qualitative characterization of flow paths and flow velocities. Stable-isotope
measurements show no direct altitude effect. Tritium values indicate that although a few springs and wells discharge pre-bomb
water, most springs discharge waters from the 1960s or later.
Received, February 1997 · Revised, September 1997 · Accepted, September 1997 相似文献
46.
R.L. Bassett 《Geochimica et cosmochimica acta》1980,44(8):1151-1160
Energy related industrial development, municipal waste treatment processes and some natural sources, contribute to B (being present) in the environment in elevated concentrations. Boron forms numerous aqueous ion pairs and complexes, some of which would not normally exist in significant concentrations under typical baseline environmental conditions. A complete understanding of the aqueous chemistry of B depends on an accurate evaluation of the thermodynamic data for these species.Equilibrium constants for 29 inorganic complexes, ion pairs, and polyanions of B have been critically evaluated. Apparent equilibrium constants have been extrapolated to zero ionic strength, and the selected thermodynamic values are tabulated. Gibbs free energies of formation for the aqueous species have been computed; these are presented with entropy and enthalpy values where available 相似文献
47.
48.