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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
381

New insights on the chemical speciation of nickel and copper in a naturally metal-rich soil from the Thetford mines area, Quebec /

Murimboh, Catherine Anne, January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2005. / Includes bibliographical references. Also available in electronic format on the Internet.
382

Understory vegetation effects on soil nitrogen and soil carbon in thinned and unthinned Douglas-fir forests /

Geyer, Eric A. January 1998 (has links)
Thesis (M.S.)--Oregon State University, 1999. / Typescript (photocopy). Includes bibliographical references (leaves 67-74). Also available on the World Wide Web.
383

Distribution of soil organic carbon and nitrogen fractions, enzyme activities and microbial diversity in temperate alley cropping systems

Mungai, Nancy Wangari. January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 75-81). Also available on the Internet.
384

Distribution of soil organic carbon and nitrogen fractions, enzyme activities and microbial diversity in temperate alley cropping systems /

Mungai, Nancy Wangari. January 2004 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 75-81). Also available on the Internet.
385

Carbon and nitrogen transformations in some forest floors

Lacelle, Larry E. H. January 1971 (has links)
An incubation technique was used to examine carbon mineralization and inorganic nitrogen accumulation in samples of Douglas-fir and alder forest floors developed over soils derived from granitic, ultrabasic and limestone parent materials in western British Columbia and Washington. Samples included L, F, and H or Hi horizons of Douglas-fir mor, raw moder, mull-like moder and mull forest floors and alder typical moder forest floors. Carbon dioxide production by the forest floor materials provided an estimate of gross carbon mineralization and an approximate indication of gross nitrogen mineralization. Comparison of inorganic nitrogen accumulated and gross carbon mineralized indicated that a large fraction of the mineralized inorganic nitrogen is immobilized by the microbial population and (or) lost to denitrification. The Hi horizons (organic horizons containing considerable incorporated mineral matter) accumulated more inorganic nitrogen than did the L and F horizons. Alder forest floors accumulated more inorganic nitrogen than did Douglas-fir forest floor materials. Alder L horizons tended to accumulate ammonium nitrogen while the F and Hi horizons accumulated nitrate nitrogen. Douglas-fir mor forest floors were distinguished from their mull and moder counterparts by slower decomposition and less inorganic nitrogen accumulation, and by largely accumulating ammonium nitrogen in all horizons. Irregular nitrogen accumulation curves, for some samples of Douglas-fir L and F horizons were probably due to denitrification losses. Incubation conditions favoring nitrification, with no plant sinks to remove accumulated inorganic nitrogen, may have favored denitrification losses. / Land and Food Systems, Faculty of / Graduate
386

Non-linear nitrogen dynamics and calcium depletion along a temperate forest soil nitrogen gradient /

Sinkhorn, Emily R. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.
387

An evaluation of chemical procedures for determining the lime requirement of soils

Vodraska, Robert Vit. January 1966 (has links)
LD2668 .T4 1966 V872 / Master of Science
388

Dilatancy effects on the constitutive modeling of granular soils

Salahuddin, Mohammed, 1959- January 1988 (has links)
Unique features of behavior of granular materials make constitutive modeling of these materials a challenge that has not yet been answered completely. Because volume changes are so important for the type of behavior exhibited by frictional materials, it is important to correctly incorporate them in constitutive models, both in terms of their rate of development and their magnitude. In this study a number of consolidated drained triaxial tests are performed to find those features of sand behavior that can be considered "material parameters" and can be used for constitutive modeling of granular soils. Special attention is given to those features of material behavior that are related to dilatancy. A number of published experimental data are also analyzed and useful trends of soil behavior are found.
389

The use of Alcoholic Salt Solutions for the Determination of Replaceable Bases in Calcareous Soils

Magistad, O. C., Burgess, P. S. 15 May 1928 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
390

Vertical Zonation of Great Soil Groups on Mt.Graham, Arizona, as Correlated with Climate, Vegetation, and Profile Characteristics

Martin, W. P., Fletcher, Joel E. 01 January 1943 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

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