東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Understanding Poorly-characterized I...

Dynarski, Katherine Annette.

FindBook

Google Book

Amazon

博客來

Understanding Poorly-characterized Inputs of Nitrogen to Terrestrial Ecosystems at Ecosystem and Global Scales.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Understanding Poorly-characterized Inputs of Nitrogen to Terrestrial Ecosystems at Ecosystem and Global Scales./
作者:	Dynarski, Katherine Annette.
出版者:	Ann Arbor : ProQuest Dissertations & Theses, : 2018,
面頁冊數:	161 p.
附註:	Source: Dissertations Abstracts International, Volume: 80-05, Section: B.
Contained By:	Dissertations Abstracts International80-05B.
標題:	Ecology. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=10931876
ISBN:	9780438629097

Understanding Poorly-characterized Inputs of Nitrogen to Terrestrial Ecosystems at Ecosystem and Global Scales.
Dynarski, Katherine Annette.

Understanding Poorly-characterized Inputs of Nitrogen to Terrestrial Ecosystems at Ecosystem and Global Scales. - Ann Arbor : ProQuest Dissertations & Theses, 2018 - 161 p.

Source: Dissertations Abstracts International, Volume: 80-05, Section: B.

Thesis (Ph.D.)--University of California, Davis, 2018.

This item is not available from ProQuest Dissertations & Theses.

Nitrogen (N) availability regulates ecosystem and structure and function, and questions regarding patterns of N availability and limitation remain central in terrestrial biogeochemistry. N enters terrestrial ecosystems via three main input pathways: biological N fixation, bedrock N weathering, and atmospheric N deposition. My dissertation addresses key uncertainties regarding these N input pathways and their interactions on ecosystem and global scales, with particular emphasis on temperate forests. Through a meta-analysis, I investigated global patterns of nutrient constraints to free-living N fixation. I showed that across diverse terrestrial ecosystems from tropical forests to the boreal, free-living N fixation is strongly suppressed by N deposition and stimulated by Mo fertilization. Additionally, free-living N fixation is stimulated by P additions in tropical forests. These findings suggest that nutrient limitation is an intrinsic property of the biochemical demands of N fixation, which has implications for understanding the causes and consequences of N limitation in coupled nutrient cycles, as well as modeling and forecasting nutrient controls over carbon-climate feedbacks. Next, I examined the interaction between free-living N fixation and bedrock N inputs in forest ecosystems in northern California and southern Oregon. I showed that forests underlain by N-rich bedrock paradoxically also exhibit higher rates of free-living N fixation. I demonstrated that these forests accumulate significantly more soil N and C, leading to increased retention of Mo and P and explaining the observed N fixation patterns. Thus, bedrock N weathering acts as an N input that is directly coupled to the forest C cycle. Finally, I investigated the influence of soil N availability on plant reliance on symbiotic N acquisition pathways, including symbiotic N fixation and mycorrhizal partnerships. I demonstrate that in N-depleted soils, many plants obtain the vast majority of their tissue N via symbiotic pathways, despite the resource cost involved. My dissertation findings highlight the importance of interactions between plants, soil nutrients, geology, and microbes in driving ecosystem and global patterns of N input pathways, and demonstrate the need for a more nuanced representation of these relationships in order to accurately represent N cycling in global models.

ISBN: 9780438629097Subjects--Topical Terms:

516476
Ecology.

Understanding Poorly-characterized Inputs of Nitrogen to Terrestrial Ecosystems at Ecosystem and Global Scales.
LDR:03683nmm a2200361 4500 001 2207372
005 20190920101644.5
008 201008s2018 ||||||||||||||||| ||eng d
020 $a 9780438629097
035 $a (MiAaPQ)AAI10931876
035 $a (MiAaPQ)ucdavis:18153
035 $a AAI10931876
040 $a MiAaPQ $c MiAaPQ
100 1 $a Dynarski, Katherine Annette. $3 3434359
245 1 0 $a Understanding Poorly-characterized Inputs of Nitrogen to Terrestrial Ecosystems at Ecosystem and Global Scales.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2018
300 $a 161 p.
500 $a Source: Dissertations Abstracts International, Volume: 80-05, Section: B.
500 $a Publisher info.: Dissertation/Thesis.
500 $a Advisor: Houlton, Benjamin Z.
502 $a Thesis (Ph.D.)--University of California, Davis, 2018.
506 $a This item is not available from ProQuest Dissertations & Theses.
506 $a This item must not be added to any third party search indexes.
506 $a This item must not be sold to any third party vendors.
520 $a Nitrogen (N) availability regulates ecosystem and structure and function, and questions regarding patterns of N availability and limitation remain central in terrestrial biogeochemistry. N enters terrestrial ecosystems via three main input pathways: biological N fixation, bedrock N weathering, and atmospheric N deposition. My dissertation addresses key uncertainties regarding these N input pathways and their interactions on ecosystem and global scales, with particular emphasis on temperate forests. Through a meta-analysis, I investigated global patterns of nutrient constraints to free-living N fixation. I showed that across diverse terrestrial ecosystems from tropical forests to the boreal, free-living N fixation is strongly suppressed by N deposition and stimulated by Mo fertilization. Additionally, free-living N fixation is stimulated by P additions in tropical forests. These findings suggest that nutrient limitation is an intrinsic property of the biochemical demands of N fixation, which has implications for understanding the causes and consequences of N limitation in coupled nutrient cycles, as well as modeling and forecasting nutrient controls over carbon-climate feedbacks. Next, I examined the interaction between free-living N fixation and bedrock N inputs in forest ecosystems in northern California and southern Oregon. I showed that forests underlain by N-rich bedrock paradoxically also exhibit higher rates of free-living N fixation. I demonstrated that these forests accumulate significantly more soil N and C, leading to increased retention of Mo and P and explaining the observed N fixation patterns. Thus, bedrock N weathering acts as an N input that is directly coupled to the forest C cycle. Finally, I investigated the influence of soil N availability on plant reliance on symbiotic N acquisition pathways, including symbiotic N fixation and mycorrhizal partnerships. I demonstrate that in N-depleted soils, many plants obtain the vast majority of their tissue N via symbiotic pathways, despite the resource cost involved. My dissertation findings highlight the importance of interactions between plants, soil nutrients, geology, and microbes in driving ecosystem and global patterns of N input pathways, and demonstrate the need for a more nuanced representation of these relationships in order to accurately represent N cycling in global models.
590 $a School code: 0029.
650 4 $a Ecology. $3 516476
650 4 $a Biogeochemistry. $3 545717
650 4 $a Soil sciences. $3 2122699
690 $a 0329
690 $a 0425
690 $a 0481
710 2 $a University of California, Davis. $b Soils and Biogeochemistry (formerly Soil Science). $3 3434360
773 0 $t Dissertations Abstracts International $g 80-05B.
790 $a 0029
791 $a Ph.D.
792 $a 2018
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=10931876