Responses to ammonium and nitrate additions by boreal plants and their natural enemies.
Environ Pollut
; 141(1): 167-74, 2006 May.
Article
em En
| MEDLINE
| ID: mdl-16199116
ABSTRACT
Separate effects of ammonium (NH4+) and nitrate (NO3-) on boreal forest understorey vegetation were investigated in an experiment where 12.5 and 50.0 kg nitrogen (N) ha(-1) year(-1) was added to 2 m2 sized plots during 4 years. The dwarf-shrubs dominating the plant community, Vaccinium myrtillus and V. vitis-idaea, took up little of the added N independent of the chemical form, and their growth did not respond to the N treatments. The grass Deschampsia flexuosa increased from the N additions and most so in response to NO3-. Bryophytes took up predominately NH4+ and there was a negative correlation between moss N concentration and abundance. Plant pathogenic fungi increased from the N additions, but showed no differences in response to the two N forms. Because the relative contribution of NH4+ and NO3- to the total N deposition on a regional scale can vary substantially, the N load a habitat can sustain without substantial changes in the biota should be set considering specific vegetation responses to the predominant N form in deposition.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Monitoramento Ambiental
/
Ecossistema
/
Poluentes Atmosféricos
/
Desenvolvimento Vegetal
/
Compostos de Amônio Quaternário
/
Nitrogênio
País/Região como assunto:
Europa
Idioma:
En
Ano de publicação:
2006
Tipo de documento:
Article