Sökning: "soil disturbance"

Visar resultat 21 - 25 av 37 avhandlingar innehållade orden soil disturbance.

  1. 21. Vegetation patterns and processes in riparian landscapes

    Författare :Birgitta Malm Renöfält; Christer Nilsson; Peter Edwards; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : The objective of this study was to increase understanding of the processes structuring and controlling the species richness of riparian plant communities. In particular, I examined the unimodal relationship, found in many rivers, between plant species richness and location along the river corridor. LÄS MER

  3. 22. Plant ecological studies related to restoration of a degraded ecosystem in central Tanzania

    Författare :Shadrack Eliapenda; Ingvar Backéus; Karin Bengtsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Conservation; land degradation; population growth rate; population structure; regeneration; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; Ecological Botany; Ekologisk botanik;

    Sammanfattning : Kondoa Irangi area is among the most degraded ecosystems in Central Tanzania as a result of heavygrazing, fire, collection of fuelwood and improper cultivation practices. The restoration process of thisdegraded ecosystem through natural regeneration is slowed by the semi-arid climate of the area combinedwith poor soil nutrient status. LÄS MER

  4. 23. Analysis of underground concrete pipelines subjected to seismic high-frequency loads

    Författare :Roghayeh Abbasiverki; Anders Ansell; Jan Laue; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Earthquake; High-frequency; Underground; Pipelines; Reinforced concrete; Inclined bedrock; Jordbävning; Högfrekvent; Underjordisk; Rörledningar pipelines ; Armerad betong; Lutande berggrund; Civil and Architectural Engineering; Byggvetenskap;

    Sammanfattning : Buried pipelines are tubular structures that are used for transportation of important liquid materials and gas in order to provide safety for human life. During an earthquake, imposed loads from soil deformations on concrete pipelines may cause severe damages, possibly causing disturbance in vital systems, such as cooling of nuclear power facilities. LÄS MER

  5. 24. Provenance, transport, and the fate of organic matter and sediments drained through Himalayan Rivers in Nepal

    Författare :Rajendra Bhandari; Joyanto Routh; Subodh Sharma; Åsa Danielsson; Rajendra Joshi; Mead Allison; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Himalayan rivers; Biomarkers; Isotopes; OC flux; RUSLE; Himalayafloder; biomarkörer; isotoper; OC flux; RUSLE;

    Sammanfattning : Despite its small area (ca. 595,000 km2), the Himalayan region transfers disproportionally high amounts of sediments and organic matter (OM) through a network of rivers into the oceanic sink. LÄS MER

  7. 25. Countermeasures against railway ground and track vibrations

    Författare :Robert Hildebrand; KTH; []
    Nyckelord :ground vibration; vibration screen; track vibration; railway vibration; seismic barrier;

    Sammanfattning : Railway track and ground vibrations are considered, with anemphasis on methods of mitigation ("countermeasures"), forapplication to wayside disturbance problems.Original field measurements from two sites in Sweden, aswell as borrowed measurements from Norway, provide vibrationresults at many points on the track, on and underneath theground surface, for a variety of trains, both with and withoutcountermeasures in-place. LÄS MER