Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences

2016

Institution
Keyword
Publication
Publication Type
File Type

Articles 271 - 280 of 280

Full-Text Articles in Life Sciences

Migratory Bird Program At The U.S. Geological Survey Patuxent Wildlife Research Center/U.S. Fish And Wildlife Service Patuxent Research Refuge: Transformations In Management And Research, R. Michael Erwin, Robert Blohm Jan 2016

Migratory Bird Program At The U.S. Geological Survey Patuxent Wildlife Research Center/U.S. Fish And Wildlife Service Patuxent Research Refuge: Transformations In Management And Research, R. Michael Erwin, Robert Blohm

Publications of the US Geological Survey

The Patuxent Wildlife Research Center (Patuxent), first known as the Patuxent Research Refuge, has a long and rich history of participation in the Department of Interior’s (DOI) cooperative efforts to protect and conserve migratory birds in North America. This chapter describes many of the events and the people involved that constitute this important timeline for international conservation of a shared wildlife resource. The Patuxent Research Refuge, renowned worldwide, is part of the National Wildlife Refuge System of the U.S. Fish and Wildlife Service (USFWS) that has, at different times and under a variety of organizational iterations, provided the physical location …


Overview Of The Endangered Species Program, Glen Smart Jan 2016

Overview Of The Endangered Species Program, Glen Smart

Publications of the US Geological Survey

In the late 1950s and early 1960s, we became increasingly aware, as a Nation, of declining populations of birds and mammals. Rates of extinction appeared to be skyrocketing and the situation was becoming critical. The country needed to take action to reverse this trend. The Federal government began to show interest in the problem and acknowledged that it needed to intervene on a hands-on basis. The Washington, D.C., office of the U.S. Fish and Wildlife Service (USFWS) began to promote a program, championed by Dr. Ray Erickson, senior scientist at headquarters, to initiate captive research and propagation of birds and …


Recent Increases In Arctic Freshwater Flux Affects Labrador Sea Convection And Atlantic Overturning Circulation, Qian Yang, Tim Dixon, Paul G. Myers, Jennifer Bonin, Don Chambers, M.R. Van Den Broeke, Mads H. Ribergaard, John Mortensen Jan 2016

Recent Increases In Arctic Freshwater Flux Affects Labrador Sea Convection And Atlantic Overturning Circulation, Qian Yang, Tim Dixon, Paul G. Myers, Jennifer Bonin, Don Chambers, M.R. Van Den Broeke, Mads H. Ribergaard, John Mortensen

School of Geosciences Faculty and Staff Publications

The Atlantic Meridional Overturning Circulation (AMOC) is an important component of ocean thermohaline circulation. Melting of Greenland’s ice sheet is freshening the North Atlantic; however, whether the augmented freshwater flux is disrupting the AMOC is unclear. Dense Labrador Sea Water (LSW), formed by winter cooling of saline North Atlantic water and subsequent convection, is a key component of the deep southward return flow of the AMOC. Although LSW formation recently decreased, it also reached historically high values in the mid-1990s, making the connection to the freshwater flux unclear. Here we derive a new estimate of the recent freshwater flux from …


Earthworms In Vermont Forest Soils: A Study Of Nutrient, Carbon, Nitrogen And Native Plant Responses, Ryan Melnichuk Jan 2016

Earthworms In Vermont Forest Soils: A Study Of Nutrient, Carbon, Nitrogen And Native Plant Responses, Ryan Melnichuk

Graduate College Dissertations and Theses

Anthropogenic activities surrounding horticulture, agriculture and recreation have increased dispersal of invasive earthworms. The introduction of earthworms initiates many physical and chemical alterations in forest soils previously unoccupied by earthworms. Three trials were performed to assess the effects of earthworms on soil-water dynamics, C and N and defensive/storage compound production by a native plant.

The first trial was a greenhouse experiment, performed to assess the impact of two ecologically contrasting invasive earthworm species on percolate and evaporative soil water loss. Mesocosms were constructed to simulate a typical forest Entisol commonly penetrated by the species of interest, Lumbricus terrestris and Amynthas …


Seasonal Evolution Of Active Layer Formation In Subarctic Peat Plateaux And Implications For Dissolved Organic Matter Composition And Transfer, Jennifer L. Hickman Jan 2016

Seasonal Evolution Of Active Layer Formation In Subarctic Peat Plateaux And Implications For Dissolved Organic Matter Composition And Transfer, Jennifer L. Hickman

Theses and Dissertations (Comprehensive)

Peat-accumulating wetlands are ecosystems whose rate of photosynthetic production of organic matter is greater than that of its decomposition, resulting in a build up of soil organic matter that may take centuries to fully decompose. Carbon (C) stocks within these ecosystems are a function of inputs from photosynthesis, and losses from heterotrophic decomposition. Due to the short growing season and overall cold climate of boreal and tundra regions, C has been accumulating within these landscapes, mostly in soil organic matter, since the last glaciation. Climate change, predicted to result in rising temperatures and increased precipitation, has begun to degrade the …


Spanish River Carbonatite: Its Benefits And Potential Use As A Soil Supplement In Agriculture, James J Jan 2016

Spanish River Carbonatite: Its Benefits And Potential Use As A Soil Supplement In Agriculture, James J

Theses and Dissertations (Comprehensive)

A critical problem facing agriculture today is being able to consistently and sustainably provide plants with adequate nutrients for growth. With this problem being exacerbated by the ever-increasing human population, new perspectives and techniques are required to ensure global food security. In order to fully realize potential solutions, however, plant growth and nutrition cannot be exclusively focused upon. The soil-microorganism-plant system is comprised of many interconnected and interdependent processes that together support plant growth: it is upon these processes that the focus must be placed. In this work, the agromineral Spanish River Carbonatite (SRC) is characterized using the framework of …


Assessing Shoreline Change And Vegetation Cover Adjacent To Back-Barrier Shoreline Stabilization Structures In Georgia Estuaries, Katherine R. Wakefield Jan 2016

Assessing Shoreline Change And Vegetation Cover Adjacent To Back-Barrier Shoreline Stabilization Structures In Georgia Estuaries, Katherine R. Wakefield

Electronic Theses and Dissertations

Anthropogenic stabilization of erosional shorelines by hard-armoring structures is used for protection of property, especially if buildings, historical monuments, cultural resources, or other infrastructure are present. The post-installation effects of shoreline stabilization structures on adjacent shorelines in the back-barrier marshes of coastal Georgia are a concern, and interest in living shorelines as erosion control devices has increased because of their use of natural materials and vegetation. AMBUR shoreline analysis software was used to calculate pre-and post-installation shoreline change rates of shorelines adjacent to riprap and bulkhead structures. There was no significant difference between the post-installation shoreline change rates of the …


Land Use And Land Cover Classification And Change Detection Using Naip Imagery From 2009 To 2014: Table Rock Lake Region, Missouri, Dexuan Sha Sha Jan 2016

Land Use And Land Cover Classification And Change Detection Using Naip Imagery From 2009 To 2014: Table Rock Lake Region, Missouri, Dexuan Sha Sha

MSU Graduate Theses

Land use and land cover (LULC) of Table Rock Lake (TRL) region has changed over the last half century after the construction of Table Rock Dam in 1959. This study uses one meter spatial resolution imagery to classify and detect the change of LULC of three typical waterside TRL regions. The main objectives are to provide an efficient and reliable classification workflow for regional level NAIP aerial imagery and identify the dynamic patterns for study areas. Seven class types are extracted by optimal classification results from year 2009, 2010, 2012 and 2014 of Table Rock Village, Kimberling City and Indian …


Juvenile Survival And Adult Return As A Function Of Freshwater Rearing Life History For Coho Salmon In The Klamath River Basin, Molly Gorman Jan 2016

Juvenile Survival And Adult Return As A Function Of Freshwater Rearing Life History For Coho Salmon In The Klamath River Basin, Molly Gorman

Cal Poly Humboldt theses and projects

The Scott and Shasta rivers, Klamath River tributaries, experience spatial disparity in habitat quality in spring and summer as a result of historical and current land-use. Juvenile Coho Salmon (Oncorhynchus kisutch) born in the upper tributary reaches often rear in natal streams before migrating to sea. However, those born in the lower reaches often encounter unsuitable habitat and emigrate during their first spring to seek non-natal rearing habitats. It is assumed that these early outmigrants are population losses. This study evaluated first-summer survival, and contribution to the adult population, of non-natal rearing juveniles in the Klamath River Basin. …


Soil Organic Matter Distribution In A Douglas-Fir-Tanoak Forest, Humboldt County, California, Hollie A. Ernest Jan 2016

Soil Organic Matter Distribution In A Douglas-Fir-Tanoak Forest, Humboldt County, California, Hollie A. Ernest

Cal Poly Humboldt theses and projects

Soil carbon (C) affects the active gases in the atmosphere, nutrient cycling, and diversity of flora and fauna. Soil organic matter (SOM) is partially comprised of C, and a widely-accepted ratio of 0.58 organic carbon (OC) to organic matter (OM) is used to measure soil C on a landscape scale. However, this ratio varies according to vegetation, depth, hydrology, and may lead to miscalculations of soil C and SOM estimates. Soil C and SOM are inherently complex and it is not completely understood which environmental factors have the most influence in their formation, which occurs on a time scale of …