Graduate Thesis Or Dissertation
 

Autonomous in situ measurements of estuarine surface PCO₂ : instrument development and initial estuarine observations

公开 Deposited

可下载的内容

下载PDF文件
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/zg64tr497

Descriptions

Attribute NameValues
Creator
Abstract
  • A novel, low-cost instrument capable of measuring surface water PCO₂ was designed for use in dynamic, shallow-water environments. The instrument was tested in the Yaquina River Estuary, a macrotidal estuary known to experience a wide range of conditions ranging from dominance by the coastal ocean during summer upwelling to substantial freshwater discharge events resulting from winter storms. This instrument depends on gas equilibration by the diffusion of CO₂ molecules through a microporous, hydrophobic membrane between the aqueous environment and an enclosed gaseous volume, and subsequent quantification of the concentration of CO₂ molecules in the equilibrated air via Non-Dispersive Infra-Red (NDIR) absorbance technology. The field-testing occurred between January and December 2013, collecting over 200 discrete samples and 30 hours of in situ data. The data collected by this instrument was compared to discrete samples analyzed in the laboratory and found to have an absolute average deviation, or imprecision, of 7%. Preliminary area-weighted average air-sea CO₂ flux estimations for the Yaquina River Estuary (3 mol C m⁻² y⁻¹) show the same order of magnitude as other estuarine studies where comparable PCO₂ measurement techniques were used, but significantly lower than studies where PCO₂ was not directly measured. The discrete sampling program executed in combination with the instrument development process allowed a closer look at the seasonality of this ecosystem. This study discusses the evidence of both physical and biogeochemical processes occurring in the study area.
License
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
权利声明
Publisher
Peer Reviewed
Language
Replaces

关联

Parents:

This work has no parents.

属于 Collection:

单件

缩略图 标题 上传日期 公开度 行动
file details WallColleenM2014.pdf 2017-11-13 公开 下载