Sökning: "avrinningsområde"

Visar resultat 16 - 20 av 28 avhandlingar innehållade ordet avrinningsområde.

  1. 16. Characterisation of Urban Rainfall in Kuala Lumpur, Malaysia

    Författare :Mohamed Nor bin Desa Mohamed; Avdelningen för Teknisk vattenresurslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; geographical and geological engineering; Hydrogeology; velocity; vector; monsoon; Malaysia; thunderstorm; Hydrogeologi; teknisk geologi; teknisk geografi; Geophysics; physical oceanography; meteorology; Geofysik; fysisk oceanografi; meteorologi;

    Sammanfattning : Rainfall characteristics of Kuala Lumpur, Malaysia, are studied in space and time; on a large scale, 550 km2, and long term scale to find out the monsoon influence, and on urban basin scale, 23 km2, to determine dynamic properties of rainfalls and spatial correlations, and on a point scale to determine the probabilities of very high rain intensities. The importance of spatial and temporal variability of rainfall was investigated applying cross correlation on long term historical rainfalls from Kuala Lumpur, Malaysia. LÄS MER

  3. 17. Observational Uncertainties in Water-Resources Modelling in Central America : Methods for Uncertainty Estimation and Model Evaluation

    Författare :Ida Westerberg; Sven Halldin; Jan Seibert; Lars-Christer Lundin; Chong-Yu Xu; Deliang Chen; Alberto Montanari; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Central America; Discharge; Flow-duration curve; Fuzzy regression; GLUE; Model evaluation; Non-stationarity; Observational uncertainty; Precipitation; Quality control; Rating curve; Regionalisation; Uncertainty estimation; Ungauged basins; Water resources; Avbördningskurva; Centralamerika; GLUE; icke-stationaritet; kvalitetskontroll; modellutvärdering; nederbörd; observationsosäkerheter; avrinningsområden utan vattenfö-ringsdata; oskarp regression; osäkerhetsuppskattning; regionalisering; varaktighetskurva; vattenföring; vattenresurser; Hydrology; Hydrologi; Hydrology; Hydrologi;

    Sammanfattning : Knowledge about spatial and temporal variability of hydrological processes is central for sustainable water-resources management, and such knowledge is created from observational data. Hydrologic models are necessary for prediction for time periods and areas lacking data, but are affected by observational uncertainties. LÄS MER

  4. 18. CO2 Emissions from Northern Lakes : Insights on regulation and spatiotemporal variability across contrasting lakes in Sweden

    Författare :David Rudberg; David Bastviken; Paul Hanson; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lake; CO2 flux; Spatiotemporal variability; Empirical models; Sjö; Koldioxid-flöde; Rumsliga och tidsmässiga variationer; Empiriska modeller;

    Sammanfattning : Lakes cover only ~2 % of the global land area, but their connections to the surrounding catchment make them important for the global carbon cycle. A considerable amount of the carbon input to lakes is emitted to the atmosphere as carbon dioxide (CO2) through diffusive flux. LÄS MER

  5. 19. Soil and stream water chemistry in a boreal catchment - interactions, influences of dissolved organic matter and effects of wood ash application

    Författare :Sara H Norström; Ulla Lundström; Dan Bylund; Mittuniversitetet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Boreal forest; catchment studies; dissolved organic carbon; soil solution; Chemistry; Kemi;

    Sammanfattning : Two small bordering catchments in Bispgården, Central Sweden, wereinvestigated in regard to soil solution and stream water chemistry during the frostfree seasons of 2003-2007. Both catchments were drained by first order streams,Fanbergsbäcken and Gråbergsbäcken, and in Fanbergsbäckens catchment anextensive investigation of the soil and soil solution chemistry was conducted bylysimeter and centrifugation sampling. LÄS MER

  7. 20. Treatment of arsenic contaminated drinking water from the sources around the gold mining areas of Geita and Mara, Tanzania : Removal efficiency of locally available materials, bauxite, gypsum and magnesite

    Författare :Regina Filemon Irunde; Prosun Bhattacharya; Felix Mtalo; Sudip Chakraborty; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arsenic; bauxite; gypsum; magnesite; natural water; removal; Visual MINTEQ; kinetic reaction; isotherms; Freundlich; Langmuir; Arseniki; bauxite; gypsum; magnesite; maji ya asili; kuondolewa; Visual MINTEQ; misuguano ya kinetic; isotherm; Freundlich; Langmuir; Arsenik; bauxit; gips; magnesit; naturligt vatten; rening; Visual MINTEQ; kinetisk reaktion; isotermer; Freundlich; Langmuir; Mark- och vattenteknik; Land and Water Resources Engineering;

    Sammanfattning : In recent years, high arsenic (As) levels of about 300 µg/L have been reported around the gold mining areas of Geita and Mara regions within the Lake Victoria basin (LVB) in Tanzania. During a sampling campaign at Geita and Mara, the groundwater and surface water samples revealed the presence of high As concentrations as well as Fe and sulfide. LÄS MER