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Manlay Raphaël J. Masse Dominique Chevallier Tiphaine Russell-Smith Anthony Friot Dominique Feller Christian 《Plant and Soil》2004,259(1-2):123-136
Potassium (K), calcium (Ca), iron (Fe) and aluminium (Al) release from Norway spruce (Picea abies Karsten), Scots pine (Pinus sylvestris L.) and silver birch (Betula pendula Roth.) logging residues (fine roots, foliage and small branches) were studied by means of litterbags over a period of three years in clear-cut area and adjacent uncut Norway spruce dominated mixed boreal forest in eastern Finland (63°51′ N, 28°58′ E, 220 m a.s.l) to determine the amounts and rates of release for these elements and to evaluate whether clear-cutting accelerates mineralization. Almost all K was released from logging residues already during the first year. Calcium was released from foliage and roots but accumulated in branches. Most of the roots Fe and Al content were released during three years while the absolute amounts of Fe and Al in branches and foliage generally increased with decomposition. The results indicate that mineralization is slightly accelerated as a result of clear-cutting since K from foliage and branches of all studied tree species and Ca from pine and spruce roots was released significantly faster at the clear-cut plot than at the forest plot. In three years the initial K pool in the logging residues declined by 90%, Ca by 8%, Fe by 55% and Al by 61% in the clear-cut area. These results indicate that Ca is retained a long time; but Fe, Al and in particular, K are soon released from logging residues. Fine roots of the logged trees release large amounts of Fe and Al and can significantly affect Fe and Al fluxes. 相似文献
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Julia K. Steinberger Damien Friot Olivier Jolliet Suren Erkman 《The International Journal of Life Cycle Assessment》2009,14(5):443-455
Background, aim, and scope Life cycle analyses (LCA) approaches require adaptation to reflect the increasing delocalization of production to emerging
countries. This work addresses this challenge by establishing a country-level, spatially explicit life cycle inventory (LCI).
This study comprises three separate dimensions. The first dimension is spatial: processes and emissions are allocated to the
country in which they take place and modeled to take into account local factors. Emerging economies China and India are the
location of production, the consumption occurs in Germany, an Organisation for Economic Cooperation and Development country.
The second dimension is the product level: we consider two distinct textile garments, a cotton T-shirt and a polyester jacket,
in order to highlight potential differences in the production and use phases. The third dimension is the inventory composition:
we track CO2, SO2, NO
x
, and particulates, four major atmospheric pollutants, as well as energy use. This third dimension enriches the analysis of
the spatial differentiation (first dimension) and distinct products (second dimension).
Materials and methods We describe the textile production and use processes and define a functional unit for a garment. We then model important processes
using a hierarchy of preferential data sources. We place special emphasis on the modeling of the principal local energy processes:
electricity and transport in emerging countries.
Results The spatially explicit inventory is disaggregated by country of location of the emissions and analyzed according to the dimensions
of the study: location, product, and pollutant. The inventory shows striking differences between the two products considered
as well as between the different pollutants considered. For the T-shirt, over 70% of the energy use and CO2 emissions occur in the consuming country, whereas for the jacket, more than 70% occur in the producing country. This reversal
of proportions is due to differences in the use phase of the garments. For SO2, in contrast, over two thirds of the emissions occur in the country of production for both T-shirt and jacket. The difference
in emission patterns between CO2 and SO2 is due to local electricity processes, justifying our emphasis on local energy infrastructure.
Discussion The complexity of considering differences in location, product, and pollutant is rewarded by a much richer understanding of
a global production–consumption chain. The inclusion of two different products in the LCI highlights the importance of the
definition of a product's functional unit in the analysis and implications of results. Several use-phase scenarios demonstrate
the importance of consumer behavior over equipment efficiency. The spatial emission patterns of the different pollutants allow
us to understand the role of various energy infrastructure elements. The emission patterns furthermore inform the debate on
the Environmental Kuznets Curve, which applies only to pollutants which can be easily filtered and does not take into account
the effects of production displacement. We also discuss the appropriateness and limitations of applying the LCA methodology
in a global context, especially in developing countries.
Conclusions Our spatial LCI method yields important insights in the quantity and pattern of emissions due to different product life cycle
stages, dependent on the local technology, emphasizing the importance of consumer behavior. From a life cycle perspective,
consumer education promoting air-drying and cool washing is more important than efficient appliances.
Recommendations and perspectives Spatial LCI with country-specific data is a promising method, necessary for the challenges of globalized production–consumption
chains. We recommend inventory reporting of final energy forms, such as electricity, and modular LCA databases, which would
allow the easy modification of underlying energy infrastructure.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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