Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 35 for “"paleolimnology"”.
-
The Paleolimnology of Sodus Bay
Assemblages of diatoms, microscopic golden algae with siliceous frustules, have been used to assess the trophic states of lakes, ponds and bays. The trophic history of Sodus Bay, Wayne County, New York was investigated through identification and enumeration of diatom valves preserved in a 1-meter …
-
Paleolimnology of selected Precambrian Shield lakes /
The analysis of fossil diatoms and Mallomonas assemblages in a 2.85 m sediment core revealed that a series of distinct floristic changes have occurred in the development of Found Lake, a small Shield lake in southern Ontario. Climatic and vegetational changes in the lake's watershed were closely …
-
Assessing Biological Recovery of Cladocera from Sudbury-Area Lakes Using Paleolimnology
Lakes near Sudbury, Ontario, experienced widespread acidification and metal-contamination beginning in the late-19th century. These stressors caused extreme damage to regional aquatic systems and their catchments, with aquatic biota experiencing reduced species richness and, in some cases, …
-
Paleolimnology and paleoecology of the Coal Valley region, Lincoln County, Nevada
During Pleistocene time, Coal Valley, Nevada, was situated between a pluvial climatic zone to the north and a non-pluvial climactic zone to the south. The Coal Lake section represents {dollar}>{dollar}20,000 years of continuous deposition, recording a saline lake phase (Early Coal Lake) present …
-
STRATIGRAPHIC FRAMEWORK AND QUATERNARY PALEOLIMNOLOGY OF THE LAKE TURKANA RIFT, KENYA
<p>Lake sediments are some of the best archives of continental climate change, particularly in the tropics. This study is focused on three ~10m sediment cores and high-resolution seismic reflection data from Lake Turkana in northern Kenya. Lake Turkana is the world's largest desert lake and the …
-
The Paleolimnology of Irondequoit Bay: Trophic History Inferred from Sedimentary Diatom Assemblages
This master thesis analyzes the condition of diatoms the Irondequoit Bay. The author was able to gather data from the past 150 years of the Bay’s history. Three core samples were taken from the bay, and each core was given a different test. These tests include diatom analysis, radiometric dating …
-
Lakes and Groundwater of the Rieti Basin, Central Italy: Hydrochemistry, Paleolimnology, and Seismologic Influences
… and analyzed to study the hydrochemistry and paleolimnology of two lakes in the Rieti Basin and adjacent groundwater springs. Chemical and stable isotopic tracers were used to characterize water samples and to examine downcore changes in sediment cores. The lakes, Lungo and Ripasottile (LUN …
-
High Resolution Paleolimnology of Lakes in the Athabasca Oil Sands Mining Region, Alberta, Canada
The Athabasca oil sands (AOS) represent one of Canada’s most economically important natural resources. Understanding the origin, fate and long-term impact of these industrial operations requires geoscientific knowledge of the potential environmental impacts. To quantify current impact an …
-
Late Pleistocene lithofacies, paleolimnology and ostracode fauna of kettles on the Illinoian till plain, Illinois, U.S.A
The response of sediment, vegetation and aquatic environments to climate change during the last glacial--interglacial--glacial intervals were investigated from fossiliferous successions in four breached kettle basins in south-central Illinois. The thickest measured successions of lacustrine/paludal …
-
Diatom-Inferred Changes in Effective Moisture From Gall Lake, Northwestern, Ontario, Over the Past Two Millennia
The boreal forest of Canada extends across 58% of Canada’s land area providing a large range of ecosystem services including flood control, water filtration, and carbon storage. Despite conservation efforts to protect this ecosystem, the boreal region is still under stress from global stressors …
-
Diatom Assemblages in Relation to Water-Depth Gradients in Eight Boreal Shield Lakes From Northwestern Ontario, Canada
The uncertainty surrounding the impact of future changes in climate and water resources has created renewed interest on how lakes have responded to drought in the past. There is a need to determine potential future available water by understanding past changes in water levels; the underlying …
-
Lacustrine Deltaic Deposits of the Sandstone Tongue of the Wasatch Formation, Fossil Basin, Wyoming
<p>Sedimentary structures and facies relations of the sandstone tongue of the Wasatch Formation in Fossil Basin, Wyoming are interpreted as indicative of a rapidly prograding bird's foot delta. Two upward coarsening siliciclastic sequences that contain bottomset, foreset, and topset beds were …
-
Paleolimnological Reconstruction of Long-Term Trends in Phototrophic Communities in Prairie Reservoirs
Anecdotal evidence suggested that Lake Diefenbaker, a large river-valley reservoir in Southern Saskatchewan, Canada, has been experiencing increased pelagic algal bloom frequency and intensity in recent years. This has raised concerns regarding possible deteriorating water quality, including taste …
-
THE RISE OF THE GREEN ALGAE: USING ALGAL PALYNOMORPHS AS PROXIES OF NATURAL EVENTS AND ANTHROPOGENIC ACTIVITIES
Anthropogenic activities can speed up eutrophication by increasing the rate of nutrient influx into lakes. Climate change threatens the health of freshwater ecosystems, increasing the frequency and intensity of harmful algal blooms and associated anoxia. The acid-resistant remains of freshwater …
-
A late Holocene paleoenvironmental reconstruction of a coastal lake in northeastern Dominican Republic
Coastal lakes, lagoons, and wetlands often provide excellent records of environmental change related to both marine and terrestrial processes. Although coastal paleoenvironments in the Caribbean have been a subject of increasing interest, long-term environmental reconstructions from lakes on the …
-
Assessing Thule Inuit impacts on High Arctic lakes and ponds : a paleolimnological approach
Until recently it has been widely believed that significant anthropogenic influences on the environment began in Canada following the onset of European colonization. However, our paleolimnological data indicate that centuries prior to European settlement, ponds on Ellesmere and Bathurst Island were …
-
The Response of Discostella Species to Climate Change at the Experimental Lakes Area, Canada
Global climate change is threatening both our water quality and quantity. Specifically, the influence of climate change on freshwater lakes includes decreased water availability, increased evapotranspiration, changes in nutrient availability, and shifts in species composition. Understanding the …
-
Assessing long-term changes in chironomid assemblages linked to past fluctuations in Leach’s Storm-Petrel populations on islands in the Western Atlantic Ocean
Nutrient loading is an important factor that can indirectly deplete dissolved oxygen concentrations in lakes. In environments where seabirds nest and breed, guano is a prominent source of nutrients that can eutrophy waterbodies. Such external nutrient inputs may deplete bottom-water oxygen, …
Page 1 of 2