Sökning: "sea urchins"

Hittade 5 avhandlingar innehållade orden sea urchins.

  1. 1. Anthropogenic Disturbances and Shifts in Tropical Seagrass Ecosystems

    Detta är en avhandling från Stockholm : Systemekologiska institutionen

    Författare :Johan S. Eklöf; Nils Kautsky; Patrik Rönnbäck; Teresa Alcoverro; [2008]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Aquaculture; feedback mechanisms; Kenya; management; overgrazing; regime shift; resilience; seagrass; seaweed farming; sea urchins; Tanzania; trophic cascades; Zanzibar; NATURAL SCIENCES; NATURVETENSKAP; Marine Ecotoxicology; marin ekotoxikologi;

    Sammanfattning : Seagrasses constitute the basis for diverse and productive ecosystems worldwide. In East Africa, they provide important ecosystem services (e.g. fisheries) but are potentially threatened by increasing resource use and lack of enforced management regulations. LÄS MER

  2. 2. Macroalgal community dynamics on coral reefs Implications for management

    Detta är en avhandling från Stockholm : Department of Systems Ecology, Stockholm University

    Författare :Erik Mörk; Nils Kautsky; Magnus Nyström; Tim R. McClanahan; Stein Fredriksen; [2011]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Macroalgae; Coral Reefs; Herbivory; Nutrients; Ecosystem change; Fish; Sea Urchins; East Africa; Marine Ecotoxicology; marin ekotoxikologi;

    Sammanfattning : Although rather inconspicuous on healthy coral reefs, macroalgae form the basis of coral food webs. Today, macroalgae are generally increasing and many reefs undergo transitions from coral to macroalgal dominance resulting from e.g. enhanced nutrient loading or increased fishing. LÄS MER

  3. 3. The role of the jelly coat and the block to polyspermy in the fertilazation os sea urchins

    Detta är en avhandling från Uppsala : Almqvist & Wiksell

    Författare :Berndt E. Hagström; [1956]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : .... LÄS MER

  4. 4. Improving and inhibiting agents acting on the gametes and on their interaction at fertilization in sea urchins

    Detta är en avhandling från Uppsala : Almqvist & Wiksell

    Författare :Elsa Wicklund; [1954]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : .... LÄS MER

  5. 5. Exploring the resilience in coral reefs

    Detta är en avhandling från Stockholm : Department of Systems Ecology, Stockholm University

    Författare :Jerker Lokrantz; Magnus Nyström; Morgan Pratchett; [2009]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Coral Reefs; Resilience; Functional Groups; Vulnerability; Overfishing; Ecosystem Indicators; Tanzania; Zanzibar; NATURAL SCIENCES Biology Terrestrial; freshwater and marine ecology Marine ecology; NATURVETENSKAP Biologi Terrestisk; limnisk och marin ekologi Marin ekologi; Natural Resources Management; naturresurshushållning;

    Sammanfattning : Considering the unprecedented global decline of coral reefs concerns about their future existence are well-justified. Safeguarding ecological resilience (i.e. the capacity of ecosystems to absorb disturbance without changing their identity) has become a prime goal for management in order to combat further degradation of coral reefs. LÄS MER