|dc.contributor.author||Sebastià, Ma. T.||
|dc.description.abstract||1. The consequences of global warming and changes in resource availability were investigated
in subalpine grasslands in the Pyrenees. These communities are considered to
be especially vulnerable to climate change because of their position at the south-western
edge of the semi-natural grassland biome in Europe.
2. Changes in patterns of above- and below-ground biomass were assessed for different
plant guilds in two experiments, in which turves were transplanted from upland to
lowland locations. The first experiment aimed to evaluate general responses to warming
and drought, and the second to disentangle the effects of possible underlying mechanisms
through resource manipulation by means of a nitrogen × phosphorus fertilization
3. The increased above-ground biomass in grassland turves transplanted to lowlands
suggested that biomass production was more temperature-limited than water-limited.
The enhancement effect found in the upland turves following phosphorus addition supported
the hypothesis of a strong limitation arising from reduced nutrient availability,
confirming the central role played by phosphorus in these grasslands and its potential
importance in the response to global change.
4. Nitrogen addition did not stimulate total biomass but affected guild composition.
Grasses dominated the uplands and at high resource levels, while forbs dominated the
lowlands and when water and nutrients decreased. The counterintuitive effect of increased
biomass with decreased water in the lowlands was related to shifts in dominance from
grasses to forbs, probably enabled by decreased nutrient availability under drought
5. Synthesis and applications. Environmental factors interacted in complex ways, producing
changes in biomass distribution and guild proportions in subalpine grassland.
In addition, the results suggested that the capability of high-altitude grasslands to
provide quality forage in summer time could be threatened in the northern Mediterranean
region under climate change conditions because of: (i) a decrease in their reliability as a
result of complex biomass interactions with temperature, water and nutrient dynamics;
(ii) expected feedback mechanisms; and (iii) compositional shifts.||ca_ES
|dc.description.sponsorship||This research was partially supported by the Catalan Government and the Thematic Catalan Network of Climate Change (CARBOCAT project), the Fundació Territori i Paisatge, the Paeria of Lleida and the Technological Forestry Centre of Catalonia. The manuscript was initially developed while the author was a visiting professor at the University College Dublin, with a fellowship from the Government of Catalonia.||ca_ES
|dc.relation.isformatof||Reproducció del document publicat a https://doi.org/10.1111/j.1365-2664.2006.01232.x||ca_ES
|dc.relation.ispartof||Journal of Applied Ecology, 2007, vol. 44, núm. 1, p. 158-167||ca_ES
|dc.rights||(c) British Ecological Society, 2007||ca_ES
|dc.title||Plant guilds drive biomass response to global warming and water availability in subalpine grassland||ca_ES