2 research outputs found
Large delay in flowering in continental versus coastal populations of a Mediterranean shrub, Globularia alypum.
8 páginas, 5 figuras.t Mediterranean ecosystems are water limited and
the current general circulation Models (GCM) and ecophysiological models forecast a warming and a further
increase of drought in the next decades. A stronger water
stress can decrease the capacity for nutrient absorption by
plants. We conducted a field experiment to simulate
forecasted drought and warming in a Mediterranean
calcareous shrubland to assess the performance of rootsurface phosphatase activities of the dominant shrub
Globularia alypum. These enzyme activities were higher
in autumn and spring, when the climate conditions were
optimal for plant activity, than in summer or winter, when
there was either lack of water or cold temperatures. A
decrease in soil moisture in drought plots decreased rootsurface phosphatase activity (29% in summer and 25% in
autumn). The decrease in root-surface phosphatase activity
in drought plots coincided with a decrease in P leaf
concentrations and P accumulation in aboveground biomass
and loss of photosynthetic capacity of some dominant shrub
species of this ecosystem, and with a tendency to increase
total soil-P. These results suggest that the expected drier
conditions in this Mediterranean shrubland in the next
decades will slow down the P uptake by plants, thereby,
diminishing the P contents in biomass and increasing total
P contents in soil in non-available forms and that this can
be, in part, attributable to a result of the decrease in rootsurface phosphatase activityThis research was supported by Spanish Government grants REN2003-04871/GLO, CGL2004-01402/BOS, and
CGL2006-04025/BOS, the Catalan government grant SGR2005-
00312, the EC Integrated FP6 ALARM (GOCE-CT-2003-506675)
Project, and a Fundación BBVA 2004 grant.Peer reviewe