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101.
Keryn Paul Phil Polglase Peter Snowdon Tivi Theiveyanathan John Raison Tim Grove Stan Rance 《New Forests》2006,31(3):513-533
There is a need to calibrate models for carbon accounting in forest systems if they are to be applied for carbon trading and
off-set schemes. One such model, Full Carbon Accounting Model (FullCAM), calculates stem mass by taking annual inputs of tree
growth in stem volume and multiplying these by basic stem wood density. Stem mass is then multiplied by user-entered coefficients
to determine the mass of other tree components. Using datasets of Pinus radiata and Eucalyptus globulus that comprised of between 73 and 187 observations, we determined empirical relationships that can be used in FullCAM to relate
basic stem wood density to stand age, and masses of bark, foliage or branches to mass of stem wood for these two species.
All fitted relationships were highly significant (p < 0.001), explaining between 35 and 89% of the variance. These calibrations were then tested using three case studies where
data on volume yield curves and repeated measures of biomass of stand components were available: one of P. radiata and two of E. globulus. Although accumulation of biomass in foliage and branches were not well predicted by the model, sensitivity analysis showed
that this was relatively unimportant to total carbon storage because of the dominance of the stem, particularly once the stand
is older than 5 years. Indeed, FullCAM accounted for 99% of the variance in measured above-ground biomass at all three sites
because calibrations for the mass of stem was reasonably well constrained. Uncertainty analysis showed that despite the standard
errors of parameters used in relationships for basic density and biomass partitioning, and for estimates of carbon contents
of tree components, we can be 95% confident that sequestration of carbon in trees and debris of Pinus radiata and Eucalyptus globulus plantations are, on average, within 13% of that predicted by FullCAM.
Ensis is a joint venture between CSIRO FFP P/L and Scion Australasia P/L 相似文献
102.
Stan B‐H Tan 《Asia Pacific viewpoint》2000,41(1):51-67
The objective of this paper is to provide an understanding of how the gap between the ‘global’ and the ‘local‐peripheral’ is bridged in the everyday life of the peasantry at a coffee pioneer front. The networks of connectivity between the spontaneous migrant‐peasants at the coffee pioneer front in the province of Dak Lak in the Central Highlands of Vietnam, and the global coffee market are explored. This set of linkages helps the peasantry to settle, despite the harsh conditions of life on the frontier. This is illustrated through a brief ethnographic account of the ‘peripheral’ characteristics of life on a coffee pioneer front. By borrowing analytical tools from actor‐network theory, the paper also illuminates the (actor) networks through which coffee finally reaches the export gate. This account suggests that global commodity production processes are often embedded in local dynamics, in this case, the political‐economy of the frontier. Further, it implies the need to transcend scales when inquiring about peasant‐market relationships in export agro‐commodity production. 相似文献
103.
The brains of the 20 goats affected with natural scrapie received at the Central Veterinary-Laboratory, Weybridge, since 1975 were examined microscopically. Lesions of a spongiform encephalopathy were found in the brainstem, cerebellum, diencephalon, corpus striatum, and also in the neopallium or cerebral cortex. The lesions in the neopallium have not previously been reported in natural scrapie in goats. Deposits of amyloid were present in the thalamus in three of the 20 goats. 相似文献
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Attention was focused to the determination of the topographical locality of different ependyma types and determination of their extent by the method of segment analysis. Brain samples of five sheep of the Slovak Merino breed were studied. Excised brains were transversally cut into segments from the frontal pole at 5mm intervals. The eighth, ninth and tenth slices were cast in paraffin and were cut in simultaneous series at 300 microns intervals, the cutting thickness being 10 microns. The paraffin slices were stained with haematoxylin-eosine, G?m?ri's chromium haematoxylin, and by the aldehyde fuchsine method after G?m?ri. Nine types of ependymal epithelium of the third cerebral ventricle were observed, according to the kind and arrangement of cells. Remarkable differences were found in the occurrence of the types of cells and in their arrangement in the ependyma at the level of the arch of the side walls and bottom of the ventricle within each segment and within the extent of the studied transversal cuts. From the viewpoint of the regulation of hypophysial functions, a significant difference exists in the structure and organization of ependyma at the locality of recessus supraopticus, recessus infundibularis and recessus mammillaris. The results of our study are in agreement with findings in laboratory animals and enrich our previous findings. 相似文献
107.
A phloxine-alcian blue (PhAB) method has been used to stain the porcine nasal mucosa for macroscopic examination. Applied to either fresh or fixed specimens it stains respiratory epithelium dark blue and non-cilated epithelium, including the metaplastic epithelia of rhinitis, bright pink. The PhAB technique is simple, inexpensive and dependable, and is suitable for routine application in the post mortem room. Stained and fixed specimens may be preserved virtually indefinitely. 相似文献
108.
Stan W. Casteel DVM PhD Brian R. Thomas ChE Peter J. South DVM 《Journal of Equine Veterinary Science》1989,9(5)
Serum potassium concentrations in horses euthanatized by intravenous injection of potassium chloride (KC1) were determined and compared to potassium concentrations in control horses euthanatized by injection of sodium pentobarbital. Horses euthanatized with 50 (n=7) or 100 (n=5) mg KCl/kg body weight had significantly higher (P<0.05) serum potassium concentrations compared to control horses, (11.3±0.8 meq/1 or 16.0±4.7 meq/1 versus 7.6±2.2 meq/1, respectively) at 2 hours after death. Both test groups sustained elevated serum potassium concentrations from 15 to 120 minutes postmortem. Whole blood potassium and serum chloride concentrations were of little diagnostic value. 相似文献
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