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Full-Text Articles in Life Sciences

Biochar As A Soil Amendment For Willow And Cottonwood Plantings In A Riparian Restoration, Brian Clyde Sechler Jan 2018

Biochar As A Soil Amendment For Willow And Cottonwood Plantings In A Riparian Restoration, Brian Clyde Sechler

Ecology & Evolutionary Biology Graduate Theses & Dissertations

Riparian areas provide some of the most valuable ecosystem services of any habitat type, both for native flora and wildlife, as well as human society. The global degradation of these critical systems makes their restoration imperative for the preservation of overall ecological integrity since depleted riparian corridors will have cascading effects that pervade upland and downstream regions alike. In western river systems there are two key limiting factors that can lead to failures during re-vegetation efforts along riparian stream banks: one is a lack of available soil nutrients, and the other is a lack of soil moisture. Biochar has been ...


Global Primate Species Decline In The Anthropocene: Threats And Triage, Kevin Bracy Knight Jan 2017

Global Primate Species Decline In The Anthropocene: Threats And Triage, Kevin Bracy Knight

Ecology & Evolutionary Biology Graduate Theses & Dissertations

The Anthropocene mass extinction, or sixth mass extinction, represents a threat to global biodiversity. The only precedents for extinction at this pace are events similar to the K-Pg extinction of the non-avian dinosaurs and over 75% of the other species on Earth at the time. To be effective, conservation science needs to rapidly change focus to a larger scale. In this dissertation, I explore several conservation avenues through the lenses of ecology and economics using global primate species to examine my hypotheses. In Chapter II, I assess shared traits among primates that may indicate increased extinction risk using a hierarchical ...


Genomics Of Adaptation And Diversification, Ryan C. Lynch Jan 2015

Genomics Of Adaptation And Diversification, Ryan C. Lynch

Ecology & Evolutionary Biology Graduate Theses & Dissertations

Recent and ongoing advances in DNA sequencing, coupled with computational developments, have opened new frontiers for understanding the structure and function of biological diversity. For my dissertation, I first addressed questions related to a low diversity community of un-cultured Atacama Desert bacteria, using a variety of sequencing approaches. The principal goal was to infer what metabolic traits these bacteria possess, which allows them to survive harsh desert conditions that other bacteria could not. Through detailed genome assembly, annotation and comparative analyses I developed a working hypothesis that trace gas metabolism (H2, CO and several organic C1 compounds) may sustain these ...


Age-Related Reproduction: Conceptual Revisions And Empirical Tests Written By Rachel Joan Wildrick, Rachel Joan Wildrick Jan 2013

Age-Related Reproduction: Conceptual Revisions And Empirical Tests Written By Rachel Joan Wildrick, Rachel Joan Wildrick

Ecology & Evolutionary Biology Graduate Theses & Dissertations

Improvement in reproductive performance with age, up to a point of senescence, is a predominant pattern among vertebrates. The proximate underpinnings of such patterns are of increasing interest to evolutionary biologists, although they are not well characterized in the literature. To facilitate greater understanding of this topic, I (1) derived a hypothesis-testing framework to delineate six social and ecological factors thought to underlie within- individual improvements in age-related reproduction (ARR), organized the current literature on this topic to summarize the support for each factor and suggested future experimental and statistical approaches. I next (2) applied this framework to identify both ...


Biogeochemical Couplings Among Earth’S Ecosystems: A Focus On Old-Growth Tropical Rainforest, Philip Graham Taylor Jan 2012

Biogeochemical Couplings Among Earth’S Ecosystems: A Focus On Old-Growth Tropical Rainforest, Philip Graham Taylor

Ecology & Evolutionary Biology Graduate Theses & Dissertations

This dissertation explores how physical and biological processes organize the interaction of carbon and nutrient cycles, which underpin life on Earth. In Chapter 2, I establish that ecosystem nitrate accrual exhibits consistent and negative nonlinear correlations with organic carbon availability along a hydrologic continuum from soils, through fresh- water systems and coastal margins, to the open ocean. Across this diversity of environments, we find evidence that resource stoichiometry strongly influences nitrate accumulation by regulating a suite of microbial processes that couple dissolved organic carbon and nitrate cycling.

In Chapter 3, I address the climate sensitivity of carbon cycling in old-growth ...