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 23 for “"hydrologic variability"”.
-
Microbial community assembly and hydrologic variability as controls on potential denitrification rates in restored freshwater wetlands
Made available in DSpace on 2018-09-27T16:30:16Z (GMT). No. of bitstreams: 3 COHEN-DISSERTATION-2018.pdf: 16901181 bytes, checksum: 054fea42926998dd176783c0ceada556 (MD5) LICENSE.txt: 4207 bytes, checksum: cf01f0a3e7002722d46489a4ebca992a (MD5) PROQUEST_LICENSE.txt: 4553 bytes, checksum: …
-
A Reconstruction of Precipitation and Hydrologic Variability on the Peruvian and Bolivian Altiplano During the Late Quaternary
… Peruvian/Bolivian Altiplano is an important hydrologic system for paleoclimate reconstruction because it is unique in its ability to record climate variability associated with the near-continental scale South American summer monsoon (SASM), which is responsible for much of the precipitation …
-
A 1400 Year Multi-Proxy Record of Hydrologic Variability in the Gulf Of Mexico: Exploring Ocean-Continent Linkages During the Late Holocene
Late Holocene climate variability includes the Little Ice Age (LIA, 450-150 BP) and the Medieval Warm Period (MWP, 1100-700 BP) that are characterized by contrasting hydrologic and thermal regimes. The degree of interaction between the North American continent and the ocean during these two abrupt …
-
Late Quaternary climate variability and terrestrial carbon cycling in tropical South America
Characterizing global and regional climate variability and climate-carbon cycle interactions in the past provides critical context for evaluating present and future climate trends. In this thesis, I use stable isotope and radiocarbon analysis of vascular plant biomarkers in lacustrine and marine …
-
Late Quaternary climate variability and terrestrial carbon cycling in tropical South America
Characterizing global and regional climate variability and climate-carbon cycle interactions in the past provides critical context for evaluating present and future climate trends. In this thesis, I use stable isotope and radiocarbon analysis of vascular plant biomarkers in lacustrine and marine …
-
Complexity, Emergence, and Self-Similar Organization in River Networks
Hydrologic predictions lie at the core of a variety of environmental studies. Often these predictions need the specification of geomorphologic properties. However, geomorphologic properties themselves change in response to hydrologic variability. Therefore, for the long term prediction we need a …
-
Landscape structure, regimes, and the co-evolution of hydrologic systems
… dissertation I discuss approaches to building hydrologic understanding in a changing world that go beyond the construction of models of ever-greater complexity. These approaches aim to develop insight into the relationship between catchment properties and hydrologic dynamics using …
-
Geochemistry of karst deposits in Borneo detailing hydroclimate variations in the Warm Pool across the late Pleistocene
Variability in the tropical ocean-atmospheric system causes global scale climate anomalies, most evident in the El Niño-Southern Oscillation’s coupled climate feedbacks. Despite being an area of high interest, many questions still remain regarding the west Pacific warm pool’s response to external …
-
Infrastructure investment and policy management of water resources for small-scale irrigated agriculture
… alternatives. The farm-level model combines hydrologic, economic, and agronomic features since it considers how hydrologic variability affects crop yield, which in turn affects the farmer's utility. Policy decision variables considered in the government subsidy/pricing model include 1) water …
-
Rivers With Borders: Bi-National Water Management Model for the St. Mary-Milk Basins
… basins is increasingly challenged by climate variability, aging infrastructure, and rigid allocation frameworks. The St. Mary and Milk River Basin, shared by Canada and the United States, is governed by the 1909 Boundary Waters Treaty and the 1921 International Joint Commission Order, which …
-
Location, location: Factors influencing greenhouse gas fluxes from the Mississippi Delta agricultural region
… habitat. This study assessed gas emission variability from the Mississippi Delta agricultural landscape and explored the effects of hydrology and hydrophytic vegetation on gas emissions.</p><p>Gas collection chambers were utilized to make gas measurements from soybean and corn farmland, …
-
QUANTIFYING EFFECTS OF SEASONAL INUNDATION ON METHANE FLUXES FROM FORESTED FRESHWATER WETLANDS
… is unclear how to relate aspects of a wetland’s hydrologic regime to the timing, magnitude, and spatial extent of its methane emissions. Furthermore, discrepancies between the magnitude of global methane emissions calculated using different techniques indicate that current methods for measuring …
-
CONTINENTAL SCALE DIAGNOSTIC EVALUATION OF MONTHLY WATER BALANCE MODELS FOR THE UNITED STATES
… models are important for the characterization of hydrologic systems, to help understand regional scale dynamics, and to identify hydro-climatic trends and systematic biases in data. Because existing models have, to-date, only been tested on data sets of limited spatial representativeness and …
-
Isotope Systematics of Gypsum and its Hydration Water
… in gypsum can provide a direct measure of past hydrologic variability. This thesis presents the development of the water extraction and isotopic measurement procedures, the calculation of the gypsum-water isotope fractionation factors, and the application of the method to constrain the …
-
Hydrologic and topographic analyses of bog turtle (Glyptemys muhlenbergii) wetlands
… knowledge gaps regarding spatial variation in hydrologic regimes and associated habitat features. Building from that research, we integrated monitoring well data, delineated habitat patches, and computed terrain-based variables from 28 bog turtle-inhabited wetlands spanning both their northern …
-
An ephemeral perspective of fluvial ecosystems: Viewing ephemeral rivers in the context of current lotic ecology
Hydrologic and material dynamics of ephemeral rivers were investigated in the Namib Desert to assess how hydrologic regimes shape the physical habitat template of these river ecosystems. An analysis of long-term hydrologic records revealed that the variation in mean annual runoff and peak discharge …
-
Archives of climate variability on Kiritimati: lacustrine, aeolian and remote sensing perspectives
… Pacific islands, together with records of modern hydrological processes, can provide information on past changes in tropical hydroclimate and test island landscape sensitivity to changes in the hydrologic cycle. For small tropical islands in particular, insight into past and present hydroclimate …
-
Temporal and spatial scaling of coupled hydrological and biogeochemical processes in river basins
… focuses on how soil moisture and the dominant hydrological processes change across a climate gradient, the factors governing these spatio-temporal patterns, and in particular, the effects of climate (i.e. aridity, seasonality). Analysis of the flow regime curves reveals the dominant runoff …
-
Legacy Nutrient Management and Remediation in Diverse Agricultural Watersheds
… with a disproportionate contribution from hydrologically connected, high-risk landscape units. Soil phosphorus accumulation remains stable or increases in many areas, indicating limited natural drawdown of legacy P under baseline conditions and underscoring the challenge of achieving …
-
Spatially variable hydrologic regimes in relation to bog turtle (Glyptemys muhlenbergii) population density
… being typified by precipitation as the major hydrologic input. Groundwater inputs are not only important in taxonomically classifying wetland type, but also contribute in important ways to bog turtle natural history. Bog turtles ectothermically regulate body temperature by utilizing thermally …
Page 1 of 2