Global ETD Search

211	The image and the realities of opium use in the later nineteenth and the first half of the twentieth centuries with special reference to the working-class of Lancashire and Cheshire Crane, Bettina Susan January 1989 (has links) No description available. 900 History and use of opium
212	Intercultural pragmatics : a Japanese-American case study LoCastro, Virginia January 1990 (has links) No description available. 410 Language use and culture
213	Mortars in old buildings and masonry conservation : A historical and practical treatise Sickels, L. B. January 1987 (has links) No description available. 720 Architectural use of mortars
214	Pre-existence language and the dynamic of metaphorical predication : The Christological use of pre-existence language in the light of Paul Ricoeur's theory of metaphor McDade, J. January 1986 (has links) No description available. 100 Christological use of language
215	Discourse as planned action Steel, S. W. D. January 1984 (has links) No description available. 410 Language use
216	The use of carbenoids in #beta#-lactam synthesis Sheppard, A. January 1987 (has links) No description available. 547 Carbenoid use in synthesis
217	Characterization of hydrogenated amorphous silicon photovoltaic cells Mohammad, Jassim M. H. January 1987 (has links) No description available. 530.41 Silicon use in semiconductors
218	An evaluatory study of the methods used in the reconstruction of historical vegetation and land-use, with reference to part of East Sussex, England Moffat, B. January 1984 (has links) No description available. 910 Sussex land use
219	User involvement with microcomputer software Wishart, Jocelyn January 1988 (has links) No description available. 005 Software use in education
220	Carbon dynamics associated with different land uses in north central Alberta Arevalo, Carmela B.M. 06 1900 (has links) Land use and land use change strongly influence the carbon (C) dynamics within ecosystems. This study quantified four aspects of land use and land use change effects: 1) ecosystem C stocks and distribution; 2) soil respiration; 3) soil C mineralization; and 4) net ecosystem productivity. Land use systems studied include agriculture (AG), 2-yr- and 9-yr-old hybrid poplar plantations (2HP and 9HP, respectively), grassland (GRA), and native forest stand (NAT). Ecosystem C stock in NAT (223 Mg C ha-1) was similar to 9HP (174 Mg C ha-1) and both were significantly greater than AG (122 Mg C ha-1), GRA (121 Mg C ha-1), and 2HP (110 Mg C ha-1). Cumulative soil C loss via soil respiration averaged over two growing seasons was in the order of: NAT (7.810.40 Mg C ha-1) > 9HP (5.510.31 Mg C ha-1) > GRA (5.230.30 Mg C ha-1) > AG (5.020.24 Mg C ha 1) > 2HP (4.280.20 Mg C ha-1). Depending on land use, seasonal heterotrophic and autotrophic respiration had respective contributions to soil respiration of up to 35 and 83%. Soil C mineralization of bulk soil across the land uses ranged between 2 to 5% of initial total organic C (Ci), with mineralization rates ranging from 0.06 to 0.12 g C mg-1 Ci d-1 and mean residence times ranging from 30 to 51 yrs. Across particle size fractions, soil C mineralization was in the order of: AG > HPs > GRA > NAT of which the coarse fractions, representing labile C, were the main source of mineralized C (79%). Mineralization increased when NAT was converted to AG; and decreased when AG was converted to HP or GRA. Net ecosystem productivity across land uses, expressed in terms of C, ranged between 2 (AG) and 11 Mg C ha-1 yr-1 (older HP). Conversion from AG to GRA increased net ecosystem productivity three-fold. When AG was converted to HP, the plantation was a C source in the first four years and became a C sink by year five. Results obtained from this study are relevant to modeling efforts designed at determining the impact of future climate change on a variety of land uses. / Soil Science Carbon Land use

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