Sökning: "invasive species"
Visar resultat 6 - 10 av 125 avhandlingar innehållade orden invasive species.
6. Seed mobility and connectivity in changing rural landscapes
Sammanfattning : The success or failure of many organisms to respond to the challenges of habitat destruction and a warming climate lies in the ability of plant species to disperse between isolated habitats or to migrate to new ranges. European semi-natural grasslands represent one of the world's most species-rich habitats at small scales, but agricultural intensification during the 20th century has meant that many plant species are left only on small fragments of former habitat. LÄS MER
7. The importance of biodiversity for ecosystem processes in sediments : experimental examples from the Baltic Sea
Sammanfattning : Aquatic sediments are, by surface, the largest habitat on Earth. A wide diversity of organisms inhabit these sediments and by their actions they have a large influence on and also mediate many ecosystem processes. LÄS MER
8. Invading Herbivory. Effects of the Golden Apple Snail (Pomacea canaliculata) in Asian Wetlands
Sammanfattning : The South American golden apple snail (Pomacea canaliculata) was intentionally introduced to aquacultures in South East Asia to produce snails for human consumption, but the aquatic snails soon escaped and started to consume large amounts of rice seedlings. The aim of this thesis was to quantify the effects of this invasive herbivore on aquatic plants in natural wetlands since previous research has focused on effects of the snail in rice fields. LÄS MER
9. The Invasion of the Zebra Mussel - Effects on Phytoplankton Community Structure and Ecosystem Function
Sammanfattning : Biological invasion has become a major threat to economy, ecology, global biodiversity and ecosystem function of aquatic ecosystems. The main aim of the thesis was to study the effects of the zebra mussel (Dreissena polymorpha), a versatile invasive species, on phytoplankton dynamics and ecosystem function of lakes. LÄS MER
10. Non-indigenous zooplankton : the role of predatory cladocerans and of copepods in trophic dynamics
Sammanfattning : Human-mediated introductions of non-indigenous species now threaten to homogenize the biota of the Globe, causing huge economic and ecological damage. This thesis studies the ecological role of 3 invasive planktonic crustaceans, the omnivorous copepod Acartia tonsa (western Atlantic and Indo-Pacific) and the predatory cladocerans, Cercopagis pengoi (Ponto-Caspian) and Bythotrephes longimanus (Eurasian). LÄS MER