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Hydrologic and Landscape Controls on Organic Matter Dynamics in the Streams of the McMurdo Dry Valleys, Antarctica
Hydrologic and Landscape Controls on Organic Matter Dynamics in the Streams of the McMurdo Dry Valleys, Antarctica
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20260202104722
- ISBN
- 9798291574591
- DDC
- 551
- 서명/저자
- Hydrologic and Landscape Controls on Organic Matter Dynamics in the Streams of the McMurdo Dry Valleys, Antarctica
- 발행사항
- [Sl] : University of Colorado at Boulder, 2025
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2025
- 형태사항
- 237 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 87-02, Section: B.
- 주기사항
- Advisor: Gooseff, Michael.
- 학위논문주기
- Thesis (Ph.D.)--University of Colorado at Boulder, 2025.
- 초록/해제
- 요약Lotic systems are not simply passive pipes, but are active sites of biogeochemical cycling, playing a crucial role in the global carbon budget. In high latitude systems, understanding organic matter dynamics is especially important for understanding how these regions may respond to future climate and environmental change. In the McMurdo Dry Valleys (MDVs) of Antarctica, the intermittent streams offer a unique opportunity to study the role of autochthonous carbon in driving in-stream biogeochemical processes, even in the absence of substantial allochthonous inputs or continuous flow.The goal of my research is to explore how landscape and hydrologic connectivity shape organic matter cycling in MDVs streams, creating hotspots of biogeochemical activity within a barren desert landscape. I first challenged the long-held assumption that snow does not contribute to MDVs streamflow. Using remote sensing, satellite imagery, and field measurements, I found that snowmelt can account for 12-25% of annual streamflow and delivers nutrients that may fuel early-season algal productivity. Next, I quantified the organic matter budget of MDVs streams and found a distinct imbalance between inputs and outputs - with aeolian inputs averaging just 0.03 g/m2/year, while organic matter exports average 25 g/m2/year. This imbalance of inputs to outputs to the system emphasizes the substantial organic matter processing that is occurring within these streams, which I quantify by measuring gross primary production and ecosystem respiration, or GPP and ER. MDVs streams were found to often be net autotrophic, with GPP and ER comparable to other intermittent streams globally and greater than other areas of the MDVs landscape. Finally, while the initial chapters of this work clarify these streams as critical zones of organic matter processing across the MDVs landscape, I found that they are disproportionately left out of Antarctic protected area designations, leaving them vulnerable to future environmental change and human disturbance.Altogether, this research highlights the important role of hydrology and landscape connectivity in driving organic matter processing in polar desert streams. More broadly, this work emphasizes that while the productivity of many streams is attributed to the allochthonous inputs from the surrounding landscape, even isolated, intermittent, low-input systems can be dynamic components of ecosystem carbon cycling.
- 일반주제명
- Hydrologic sciences
- 일반주제명
- Biogeochemistry
- 일반주제명
- Ecology
- 일반주제명
- Microbiology
- 일반주제명
- Aquatic sciences
- 키워드
- Antarctica
- 키워드
- Organic matter
- 기타저자
- University of Colorado at Boulder Environmental Studies
- 기본자료저록
- Dissertations Abstracts International. 87-02B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
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■00520260202104722
■006m o d
■007cr#unu||||||||
■020 ▼a9798291574591
■035 ▼a(MiAaPQ)AAI32121593
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a551
■1001 ▼aWright, Anna Thrane.▼0(orcid)0009-0003-4709-151x
■24510▼aHydrologic and Landscape Controls on Organic Matter Dynamics in the Streams of the McMurdo Dry Valleys, Antarctica
■260 ▼a[Sl]▼bUniversity of Colorado at Boulder▼c2025
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2025
■300 ▼a237 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 87-02, Section: B.
■500 ▼aAdvisor: Gooseff, Michael.
■5021 ▼aThesis (Ph.D.)--University of Colorado at Boulder, 2025.
■520 ▼aLotic systems are not simply passive pipes, but are active sites of biogeochemical cycling, playing a crucial role in the global carbon budget. In high latitude systems, understanding organic matter dynamics is especially important for understanding how these regions may respond to future climate and environmental change. In the McMurdo Dry Valleys (MDVs) of Antarctica, the intermittent streams offer a unique opportunity to study the role of autochthonous carbon in driving in-stream biogeochemical processes, even in the absence of substantial allochthonous inputs or continuous flow.The goal of my research is to explore how landscape and hydrologic connectivity shape organic matter cycling in MDVs streams, creating hotspots of biogeochemical activity within a barren desert landscape. I first challenged the long-held assumption that snow does not contribute to MDVs streamflow. Using remote sensing, satellite imagery, and field measurements, I found that snowmelt can account for 12-25% of annual streamflow and delivers nutrients that may fuel early-season algal productivity. Next, I quantified the organic matter budget of MDVs streams and found a distinct imbalance between inputs and outputs - with aeolian inputs averaging just 0.03 g/m2/year, while organic matter exports average 25 g/m2/year. This imbalance of inputs to outputs to the system emphasizes the substantial organic matter processing that is occurring within these streams, which I quantify by measuring gross primary production and ecosystem respiration, or GPP and ER. MDVs streams were found to often be net autotrophic, with GPP and ER comparable to other intermittent streams globally and greater than other areas of the MDVs landscape. Finally, while the initial chapters of this work clarify these streams as critical zones of organic matter processing across the MDVs landscape, I found that they are disproportionately left out of Antarctic protected area designations, leaving them vulnerable to future environmental change and human disturbance.Altogether, this research highlights the important role of hydrology and landscape connectivity in driving organic matter processing in polar desert streams. More broadly, this work emphasizes that while the productivity of many streams is attributed to the allochthonous inputs from the surrounding landscape, even isolated, intermittent, low-input systems can be dynamic components of ecosystem carbon cycling.
■590 ▼aSchool code: 0051.
■650 4▼aHydrologic sciences
■650 4▼aBiogeochemistry
■650 4▼aEcology
■650 4▼aMicrobiology
■650 4▼aAquatic sciences
■653 ▼aAntarctica
■653 ▼aAutochthonous carbon
■653 ▼aOrganic matter
■653 ▼aAntarctic polar desert
■653 ▼aBiogeochemical cycling
■690 ▼a0388
■690 ▼a0425
■690 ▼a0410
■690 ▼a0329
■690 ▼a0792
■71020▼aUniversity of Colorado at Boulder▼bEnvironmental Studies.
■7730 ▼tDissertations Abstracts International▼g87-02B.
■790 ▼a0051
■791 ▼aPh.D.
■792 ▼a2025
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17358581▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
