Search for dissertations about: "clay soil"

Showing result 1 - 5 of 97 swedish dissertations containing the words clay soil.

  2. 1. Nitrogen Losses from a Clay-rich Soil used for Cereal Production in south-western Sweden

    Author : Magdalena Wallmann; Göteborgs universitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; nitrogen; fertilisers; soil; nitrous oxide; nitrogen leaching; 15N; nitrogen use efficiency; nitrogen budget; agriculture; Sweden;

    Abstract : Addition of fertiliser nitrogen (N) in crop production increases yields and protein contents, but all is not taken up by the crop. Instead, some of the N is lost to air and waters, contributing e.g. to climate change, stratospheric ozone depletion, eutrophication and acidification. READ MORE

  4. 2. Nitrous oxide emission from soil : On extrapolation from soil environmental factors

    Author : Kerstin Robertson; Linköpings universitet; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; N20 emission; denitrification; soil factors; soil moisture; N03-; NH4 ; regression analysis; PLS analysis; IR remote sensing; INTERDISCIPLINARY RESEARCH AREAS; TVÄRVETENSKAPLIGA FORSKNINGSOMRÅDEN;

    Abstract : Nitrous oxide(N20) is a natural component of the atmosphere which contributes both to the greenhouse effect and to the destruction of stratospheric ozone. National as well as global inventories indicate thatboth natural and anthropogenic emissions from terrestrial ecosystems constitute a large fraction of the annual loading of N20 on the atmosphere. READ MORE

  5. 3. Effects of structure liming on clay soil

    Author : Jens Blomquist; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Abstract : Structure lime, comprising 80-85% ground limestone (CaCO3) and 15-20% slaked lime (Ca(OH)2), is applied to clay soils to counteract losses of particulate phosphorus (PP) through aggregate stabilisation. This thesis evaluated the effect of structure lime on soil aggregate stability, aggregate size distribution, draught requirement in tillage and crop yield. READ MORE

  6. 4. Effect of Compactive Effort on the Behaviour of a Gypsiferous Subgrade Soil

    Author : Dina K Kuttah; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gypsum; Soil; Clay; Compaction; California bearing ratio; Triaxial; Moisture content; Pore water pressure; 62 Road: Soil mechanics; 62 Road: Soil mechanics;

    Abstract : Presented in this thesis is a study of the effect of compactive effort and long-term soaking on strength, stiffness and deformation characteristics of a gypsiferous subgrade soil from Kirkuk city.The tested soil is sandy lean clay (CL) according to the Unified Soil Classification System and A-6 (6) soil according to AASHTO soil classification system. READ MORE

  7. 5. Stabilization of fine-grained soils in cold environment and exposed to seasonal frost : By-products as hydraulic binders

    Author : Mirja Rothhämel; Jan Laue; Sven Knutsson; Craig Lake; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; soft soil; clay; silt; silty sand; soil stabilisation; hydraulic binder; cement; lime; by-product; cement kiln dust CKD ; cold climate; frost; freeze-thaw; laboratory test; field test; subsoil; road construction; feinkörninge Böden; Ton; Schluff; schluffiger Sand; Bodenstabilisierung; hydraulische Bindemittel; Zement; Kalk; Nebenprodukt; Zementofenstaub; kaltes Klima; Frost; Frost-Tau; Laborversuche; Feldversuche; Verkehrsbau; Dauerhaftigkeit; finkornig jord; lera; silt; siltig sand; jordstabilisering; hydraulisk bindemedel; cement; kalk; biprodukt; cement kiln dust CKD ; kallt klimat; frost; frysning-tining; laboratorieanalyser; fältförsök; vägterrass; Geoteknik; Soil Mechanics;

    Abstract : This doctoral thesis deals with the stabilization of fine-grained soils using by-product originated hydraulic binders. The use of fine-grained soils as subsoil for infrastructure projects is often limited because of the risk for instability. READ MORE