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

Photodegradation Stimulates Microbia...

Romich, Trevor L.

FindBook

Google Book

Amazon

博客來

Photodegradation Stimulates Microbial Activity Through Enhanced Water Solubility of Grass Litter Carbon.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Photodegradation Stimulates Microbial Activity Through Enhanced Water Solubility of Grass Litter Carbon./
作者:	Romich, Trevor L.
出版者:	Ann Arbor : ProQuest Dissertations & Theses, : 2020,
面頁冊數:	59 p.
附註:	Source: Masters Abstracts International, Volume: 81-11.
Contained By:	Masters Abstracts International81-11.
標題:	Biogeochemistry. -
電子資源:	https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=27828959
ISBN:	9798643196532

Photodegradation Stimulates Microbial Activity Through Enhanced Water Solubility of Grass Litter Carbon.
Romich, Trevor L.

Photodegradation Stimulates Microbial Activity Through Enhanced Water Solubility of Grass Litter Carbon. - Ann Arbor : ProQuest Dissertations & Theses, 2020 - 59 p.

Source: Masters Abstracts International, Volume: 81-11.

Thesis (M.A.)--University of California, Santa Barbara, 2020.

This item must not be sold to any third party vendors.

Solar radiation is an important contributing factor to decomposition in drylands. Research suggests that in the presence of water, previously irradiated plant litter experiences greater microbial decay than litter which was not exposed to radiation. It is unclear how exactly radiation alters litter to allow this photopriming of microbial decomposition. However, the relationship to water suggests that radiation may make litter more water-soluble, and therefore more accessible to decomposers once water enters the system. I tested the hypothesis that the abiotic impact of solar radiation on grass litter would (1) increase the production of dissolved organic carbon (DOC) when litter is subsequently extracted with water, and (2) produce DOC that stimulates more microbial activity compared to unexposed litter. Dried senesced grass litter from three species, Bromus diandrus, Avena fatua, and Hordeum murinum, were placed in sealed bags and subjected to abiotic decomposition in either an outdoor experiment or an indoor experiment. Treated litter was then soaked in water, and the extract was analyzed to determine the dissolved organic carbon concentration and its bioavailability. Exposure to radiation resulted in more DOC for all species in both the indoor and outdoor experiments, suggesting that solar radiation does enhance solubility of grass litter. During a microbial incubation, I observed a significant increase in CO2 production and a marginally significant increase in DOC consumption for samples exposed to more radiation in the indoor experiment. However, as a fraction of initial DOC available, radiation reduced these measures of microbial activity. This indicates that photodegradation produces compounds which are relatively difficult for microbes to decompose, but photodegradation can still stimulate microbial activity by increasing the total amount of available dissolved carbon. Taken together, these results suggest a possible mechanism for observed increases in mass loss due to photopriming: litter carbon is made more soluble by radiation, and is mobilized in the presence of water, allowing for increased microbial decomposition. This insight into decomposition mechanisms could aid in developing more mechanistic models of carbon cycling that include photopriming.

ISBN: 9798643196532Subjects--Topical Terms:

545717
Biogeochemistry.
Subjects--Index Terms:

Decomposition

Photodegradation Stimulates Microbial Activity Through Enhanced Water Solubility of Grass Litter Carbon.
LDR:03503nmm a2200385 4500 001 2279687
005 20210823083418.5
008 220723s2020 ||||||||||||||||| ||eng d
020 $a 9798643196532
035 $a (MiAaPQ)AAI27828959
035 $a AAI27828959
040 $a MiAaPQ $c MiAaPQ
100 1 $a Romich, Trevor L. $3 3558157
245 1 0 $a Photodegradation Stimulates Microbial Activity Through Enhanced Water Solubility of Grass Litter Carbon.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2020
300 $a 59 p.
500 $a Source: Masters Abstracts International, Volume: 81-11.
500 $a Advisor: King, Jennifer Y.
502 $a Thesis (M.A.)--University of California, Santa Barbara, 2020.
506 $a This item must not be sold to any third party vendors.
520 $a Solar radiation is an important contributing factor to decomposition in drylands. Research suggests that in the presence of water, previously irradiated plant litter experiences greater microbial decay than litter which was not exposed to radiation. It is unclear how exactly radiation alters litter to allow this photopriming of microbial decomposition. However, the relationship to water suggests that radiation may make litter more water-soluble, and therefore more accessible to decomposers once water enters the system. I tested the hypothesis that the abiotic impact of solar radiation on grass litter would (1) increase the production of dissolved organic carbon (DOC) when litter is subsequently extracted with water, and (2) produce DOC that stimulates more microbial activity compared to unexposed litter. Dried senesced grass litter from three species, Bromus diandrus, Avena fatua, and Hordeum murinum, were placed in sealed bags and subjected to abiotic decomposition in either an outdoor experiment or an indoor experiment. Treated litter was then soaked in water, and the extract was analyzed to determine the dissolved organic carbon concentration and its bioavailability. Exposure to radiation resulted in more DOC for all species in both the indoor and outdoor experiments, suggesting that solar radiation does enhance solubility of grass litter. During a microbial incubation, I observed a significant increase in CO2 production and a marginally significant increase in DOC consumption for samples exposed to more radiation in the indoor experiment. However, as a fraction of initial DOC available, radiation reduced these measures of microbial activity. This indicates that photodegradation produces compounds which are relatively difficult for microbes to decompose, but photodegradation can still stimulate microbial activity by increasing the total amount of available dissolved carbon. Taken together, these results suggest a possible mechanism for observed increases in mass loss due to photopriming: litter carbon is made more soluble by radiation, and is mobilized in the presence of water, allowing for increased microbial decomposition. This insight into decomposition mechanisms could aid in developing more mechanistic models of carbon cycling that include photopriming.
590 $a School code: 0035.
650 4 $a Biogeochemistry. $3 545717
650 4 $a Physical geography. $3 516662
650 4 $a Soil sciences. $3 2122699
653 $a Decomposition
653 $a Dissolved organic carbon
653 $a Lignin
653 $a Photodegradation
653 $a Photopriming
653 $a Plant litter
690 $a 0425
690 $a 0368
690 $a 0481
710 2 $a University of California, Santa Barbara. $b Geography. $3 1025686
773 0 $t Masters Abstracts International $g 81-11.
790 $a 0035
791 $a M.A.
792 $a 2020
793 $a English
856 4 0 $u https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=27828959