Linked Life Data

12125733

Source:http://linkedlifedata.com/resource/pubmed/id/12125733

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-7-19
pubmed:abstractText
The marker variables, Ellenberg Nitrogen Index, nitrous oxide and nitric oxide fluxes and foliar nitrogen, were used to define the impacts of NH3 deposition from nearby livestock buildings on species composition of woodland ground flora, using a woodland site close to a major poultry complex in the UK. The study centred on 2 units in close proximity to each other, containing 350,000 birds, and estimated to emit around 140,000 kg N year(-1) as NH3. Annual mean concentrations of NH3 close to the buildings were very large (60 microg m(-3)) and declined to 3 microg m(-3) at a distance of 650 m from the buildings. Estimated total N deposition ranged from 80 kg N ha(-1) year(-1) at a distance of 30 m to 14 kg N ha(-1) year(-1) at 650 m downwind. Emissions of N2O and NO were 56 and 131 microg N m(-2) h(-1), respectively at 30 m and 13 and 80 microg N m(-2) h(-1), respectively at 250 m downwind of the livestock buildings. Species number in woodland ground flora downwind of the buildings remained fairly constant for a distance of 200 m from the units then increased considerably, doubling at a distance of 650 m. Within the first 200 m downwind, trends in plant species composition were hard to discern because of variations in tree canopy composition and cover. The mean Ellenberg N Index ranged from 6.0 immediately downwind of the livestock buildings to 4.8 at 650 m downwind. The mean abundance weighted Ellenberg N Index also declined with distance from the buildings. Tissue N concentrations in trees, herbs and mosses were all large, reflecting the substantial ammonia emissions at this site. Tissue N content of ectohydric mosses ranged from approximately 4% at 30 m downwind to 1.6% at 650 m downwind. An assessment of the relative merits of the three marker variables concludes, that while Ellenberg Index and trace gas fluxes of N2O and NO give broad indications of impacts of ammonia emissions on woodland vegetation, the application of a critical foliar N content for ectohydric mosses is the most useful method for providing spatial information which could be of value to policy developers and planners.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0269-7491
pubmed:author
pubmed:issnType
Print
pubmed:volume
119
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9-21
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Defining the spatial impacts of poultry farm ammonia emissions on species composition of adjacent woodland groundflora using Ellenberg Nitrogen Index, nitrous oxide and nitric oxide emissions and foliar nitrogen as marker variables.
pubmed:affiliation
Centre for Ecology and Hydrology, Penicuik, Midlothian, UK. cerp@ceh.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't