Linked Life Data

19085012

Source:http://linkedlifedata.com/resource/pubmed/id/19085012

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2009-2-16
pubmed:abstractText
Variation in the stable N isotope ratio (delta15N) of plants and soils often reflects the influence of environment on the N cycle. We measured leaf delta15N and N concentration ([N]) on all individuals of Prosopis glandulosa (deciduous tree legume), Condalia hookeri (evergreen shrub), and Zanthoxylum fagara (evergreen shrub) present within a belt transect 308 m long x 12 m wide in a subtropical savanna ecosystem in southern Texas, USA in April and August 2005. Soil texture, gravimetric water content (GWC), total N and delta15N were also measured along the transect. At the landscape scale, leaf delta15N was negatively related to elevation for all the three species along this topoedaphic sequence. Changes in soil delta15N, total N, and GWC appeared to contribute to this spatial pattern of leaf delta15N. In lower portions of the landscape, greater soil N availability and GWC are associated with relatively high rates of both N mineralization and nitrification. Both soil delta15N and leaf [N] were positively correlated with leaf delta15N of non-N2 fixing plants. Leaf delta15N of P. glandulosa, an N2-fixing legume, did not correlate with leaf [N]; the delta15N of P. glandulosa's leaves were closer to atmospheric N2 and significantly lower than those of C. hookeri and Z. fagara. Additionally, at smaller spatial scales, a proximity index (which reflected the density and distance of surrounding P. glandulosa trees) was negatively correlated with leaf delta15N of C. hookeri and Z. fagara, indicating the N2-fixing P. glandulosa may be important to the N nutrition of nearby non-N2-fixing species. Our results indicate plant 15N natural abundance can reflect the extent of N retention and help us better understand N dynamics and plant-soil interactions at ecosystem and landscape scales.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1432-1939
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
159
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
493-503
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Spatial variation of the stable nitrogen isotope ratio of woody plants along a topoedaphic gradient in a subtropical savanna.
pubmed:affiliation
Department of Ecosystem Science and Management, Texas A&M University, College Station, TX 77843-2138, USA. ebai@ucdavis.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.