Nitrogen form and concentration interact to affect the performance of two ecologically distinct Mediterranean forest trees

Most studies examining inorganic N formeffects on growth and nutrition of forest trees have beenconducted on single species from boreal or temperateenvironments, while comparative studies with species fromother biomes are scarce. We evaluated the response of twoMediterranean trees of contrasting eco...

ver descrição completa

Detalhes bibliográficos
Autores: Uscola Fernández, María Mercedes|||0000-0002-6922-2889, Oliet Palá, Juan Antonio, Villar Salvador, Pedro|||0000-0001-9338-4530, Díaz Pinés, Eugenio, Jacobs, Douglass F.
Tipo de documento: artigo
Data de publicação:2014
País:España
Recursos:Universidad de Alcalá (UAH)
Repositório:e_Buah Biblioteca Digital Universidad de Alcalá
Idioma:inglês
OAI Identifier:oai:ebuah.uah.es:10017/37430
Acesso em linha:http://hdl.handle.net/10017/37430
https://dx.doi.org/10.1007/s10342-013-0749-3
Access Level:Acceso aberto
Palavra-chave:Ammonium
Ecophysiology
Growth
Nitrate
Pinus halepensis
Quercus ilex
Medio Ambiente
Environmental science
Descrição
Resumo:Most studies examining inorganic N formeffects on growth and nutrition of forest trees have beenconducted on single species from boreal or temperateenvironments, while comparative studies with species fromother biomes are scarce. We evaluated the response of twoMediterranean trees of contrasting ecology, Quercus ilex L.and Pinus halepensis Mill., to cultivation with distinctinorganic N forms. Seedlings were fertilized with differentNH4?/NO3- proportion at either 1 or 10 mM N. In bothspecies, N forms had small effects at low N concentration,but at high N concentration they markedly affected theplant performance. A greater proportion of NH4? in thefertilizer at high N caused toxicity as it reduced growth andcaused seedling death, with the effect being greater in Q.ilex than in P. halepensis. An increase in the proportion ofNO3- at high N strongly enhanced growth relative to lowN plants in P. halepensis but had minor effects in Q. ilex.Relatively more NH4? in the fertilizer enhanced plant Pconcentration but reduced K concentration in both species,while the opposite effect occurred with NO3-, and these effects were enhanced under high N concentration. We conclude that species responses to inorganic N forms were related to their ecology. P. halepensis, a pioneer tree, had improved performance with NO3 - at high N concentration and showed strong plasticity to changes in N supply. Q. ilex, a late successional tree, had low responsiveness to N form or concentration.