Sökning: "semiarid"

Visar resultat 1 - 5 av 16 avhandlingar innehållade ordet semiarid.

  1. 1. Water erosion modeling using fractal rainfall disaggregation- a study in semiarid Tunisia

    Författare :Sihem Jebari; Avdelningen för Teknisk vattenresurslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reservoir siltation; regionalization; fractal analysis; Atlasic mountain range; erosive events; semiarid area; soil loss; Tunisia.; Soil erosion; semiarid; Tunisia; rainfall; fractal; diaggregation;

    Sammanfattning : In the Tunisian semiarid area, water erosion processes have led to negative economic and environmental consequences in a context of limited water resources. To characterize and predict these degradation phenomena, a comprehensive high-resolution data base on erosive rainfall, together with siltation records for 28 small reservoirs were analyzed. LÄS MER

  3. 2. Food insecurity and coping strategies in semiarid areas : the case of Mvumi in central Tanzania

    Författare :Emma T. Liwenga; Tor A Benjaminsen; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Food insecurity; semiarid; local knowledge; seasonality; coping strategies; livelihood strategies.; Human geography; Kulturgeografi; Human Geography; kulturgeografi;

    Sammanfattning : This study examines how people in dryland areas cope with food insecurity and adversities over time. It draws from the experience of the Gogo people living in Mvumi in the semiarid zone of central Tanzania, an area with a long history of food shortages. The study specifically examines the potential for dryland resources to sustain livelihoods. LÄS MER

  4. 3. Unsaturated Solute Transport in a Semiarid Catchment - Nonlinear Analyses and Modelling

    Författare :Pernilla Öhrström; Avdelningen för Teknisk vattenresurslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; teknisk geografi; Hydrogeologi; teknisk geologi; unsaturated zone; Hydrogeology; geographical and geological engineering; solute transport; scaling; soils; semiarid regions; heterogeneity; preferential flow; fractals;

    Sammanfattning : Unsaturated solute transport is highly variable and therefore difficult to predict. In semi-arid areas, where water resources are limited, the presence of macropores is of great importance for crop production. The bromide ion (Br-) and dye tracers are useful for studies of water movement. LÄS MER

  5. 4. The importance of tree cover for water resources in semiarid West Africa

    Författare :Aida Bargues Tobella; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : The current paradigm in forest hydrology implies that an increase in tree cover always leads to reduced water yields as a result of increased interception and transpiration (ET) losses. This trade-off theory, in which more trees mean less water, has led to concerns that the establishment of trees in drylands may jeopardize scarce water resources. LÄS MER

  7. 5. Sustainability of irrigated agriculture under salinity pressure – A study in semiarid Tunisia

    Författare :Fethi Bouksila; Avdelningen för Teknisk vattenresurslära; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES;

    Sammanfattning : In semiarid and arid Tunisia, water quality and agricultural practices are the major contributing factors to the degradation of soil resources threatening the sustainability of irrigation systems and agricultural productivity. Nowadays, about 50% of the total irrigated areas in Tunisia are considered at high risk for salinization. LÄS MER