Search for dissertations about: "Systems Ecology"

Showing result 11 - 15 of 336 swedish dissertations containing the words Systems Ecology.

  2. 11. Irrigation with saline water using low-cost drip-irrigation systems in sub-Saharan Africa

    Author : Louise Karlberg; Per-Erik Jansson; Reinder Feddes; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Water use efficiency; Radiation use efficiency; Management techniques; Modelling; Tomato; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Abstract : In the scope of future population support, agricultural productivity, in particular in sub-Saharan Africa, has to increase drastically to meet the UN’s millennium development goals of eradicating extreme poverty and hunger by 2015. Water availability in the root-zone limits crop production in large parts of the developing world. READ MORE

  4. 12. Network Based Tools and Indicators for Landscape Ecological Assessments, Planning, and Design

    Author : Andreas Zetterberg; Berit Balfors; Ulla Mörtberg; Jan Bengtsson; KTH; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Least-cost modeling; Functional connectivity; Environmental planning tool; Resilience; Spatial redundancy; Ecological integrity; Landscape Ecology; Graph Theory; Ecological Network Graphs; Biodiversity; Conservation Biology; Urban Planning; Regional Planning; EIA; SEA; Environmental Assessment; Ecological Indicator; Impact prediction; Habitat suitability; Species distribution; Urban ecology; GIS; Urbanization; Miljöbedömningsverktyg; Landskapsplanering; Resiliens; Ekologisk integritet; Landskapsekologi; Grafteori; Ekologiska nätverk; Biologisk mångfald; Bevarandebiologi; Urban planering; Regional planering; MKB; SMB; Miljöbedömning; Ekologisk indikator; Konsekvensbedömning; Habitatmodellering; GIS; Urbanisering; Nature conservation and landscape management; Natur- och landskapsvård; Environmental engineering; Miljöteknik; Terrestrial ecology; Terrestisk ekologi;

    Abstract : Land use change constitutes a primary driving force in shaping social-ecological systems world wide, and its effects reach far beyond the directly impacted areas. Graph based landscape ecological tools have become established as a promising way to efficiently explore and analyze the complex, spatial systems dynamics of ecological networks in physical landscapes. READ MORE

  5. 13. The aquatic microbial food web and occurence of predation-resistant and potentially pathogenic bacteria, such as Francisella tularensis

    Author : Johanna Thelaus; Agneta Andersson; Mats Forsman; Farooq Azam; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; bacteria; protozoa; ecology; predation; nutrient-availability; microbial food web; model; predation-resistance; Francisella; reservoir; biofilm formation; Freshwater ecology; Limnisk ekologi;

    Abstract : All natural aquatic systems harbour a vast variety of microorganisms. In the aquatic microbial food web, the larger microorganisms (i.e. protozoa) feed on the smaller microorganisms (i. READ MORE

  6. 14. Direct and indirect effects of fish predation and excretion in aquatic food webs

    Author : José Luiz Attayde; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; zooplankton; resilience; predation; phytoplankton; nutrient enrichment; nutrient recycling; interaction strength; herbivory; food webs; food chain; excretion; fish; detritus; detritivory; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

    Abstract : The aim of this thesis was to elucidate the mechanisms by which planktivorous fish can affect planktonic communities in lakes and how they may affect benthic communities through their effects on planktonic communities. In a laboratory experiment, nutrients released by fish increased algal biomass and altered phytoplankton community structure, suggesting that fish can affect phytoplankton by directly releasing nutrients. READ MORE

  7. 15. The role of young-of-the-year fish in lake ecosystems

    Author : Pia Romare; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; Rutilus rutilus; Perca fluviatilis; diet-dependent growth; density dependent growth; behavioural cascade; 0 fish behaviour; horizontal echo sounding; biomanipulation; trophic cascade; predation pressure; young-of-the-year fish; trophic interactions; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

    Abstract : Food chain theory is based on consumption; that is, presupposing that the only important interaction between organisms is that they actually meet in an unstructured environment and that one of them is consumed. Recently, studies, including biomanipulation projects, have indicated that trophic interactions are more complex than predicted by food chain theory. READ MORE