Sökning: "Detrital"
Visar resultat 31 - 35 av 39 avhandlingar innehållade ordet Detrital.
31. Reef biostromes and related facies from the Middle Silurian of Gotland, Sweden
Sammanfattning : Reef biostromes and related facies from the upper part of Wenlock and from Ludlow were investigated in order to account for their formation, their palaeoecology and biology. In the Hemse Group of Ludlow age, all studied biostromes comprise a low diversity fauna where one or few species dominates. LÄS MER
32. Hydrogeochemical effects of hydropower regulation on river-aquifer continuum in boreal rivers
Sammanfattning : Hydropower infrastructure affects many large rivers worldwide, threatening riverine and coastal ecosystems by fragmenting flow, disturbing landscapes and water retention and altering sedimentation and primary production. This thesis investigated major impacts of hydropower regulation on hydrological and geochemical processes in large boreal rivers. LÄS MER
33. Food Quality for Zooplankton in Humic Lakes
Sammanfattning : Food quality affects growth, reproduction and community structure of zooplankton, and has implications for nutrient cycling and the transfer of energy and matter in aquatic food chains. While the issue of food quality in clear water lakes has received great recent attention, studies on food quality for zooplankton in humic lakes are scarce. LÄS MER
34. Iron in the Lena River basin, NE Russia : Insights from microscopy, spectroscopy and isotope analysis
Sammanfattning : Iron is an important mediator of biotic and abiotic processes on the Earth’s surface, being an electron acceptor in organic matter degradation, a surface for organic matter and trace element adsorption, and a required element for enzymatic processes during primary production. Yet, the role of iron as a mediator of carbon and trace element cycling in high latitude, permafrost-dominated regions remains poorly investigated. LÄS MER
35. Evolution of continental crust in the Proterozoic : growth and reworking in orogenic systems
Sammanfattning : To understand the growth of continental crust, the balance between juvenile mantle derived extraction, infracrustal reworking and crustal recycling, needs to be estimated. Since the beginning of the century, the use of coupled in situ zircon U–Pb, Lu–Hf and O isotope analyses as a tool to address these questions have increased exponentially. LÄS MER