The study highlights the changes occurred in 10 homogeneous stands both of Vaccinium and Nardus communities of the Emilian Apennines after 30 years from the first surveys. The stands were sampled by phytosociological and phenological methods in the years 1981-1984 (Puppi, Zanotti & Speranza, 1994 - Phenological studies on Vaccinium and Nardus communities. Fitosociologia) near the mount “Corno alle Scale” (BO). In that time, the locations of the stands were exactly recorded (CRT map 1:10000) and documented by series of photos. In 2011 and 2012 the original sites were found again and the same types of surveys were repeated, with the aim to detect any change and to investigate its possible causes. Main results are here summarized. Community’s structure has become more complex: in particular, Juniperus nana cover is significantly increased; moreover, among Vaccinium species, V.gaultheriodes is going to prevail on V. myrtillus, probably damaged by the shortening of the snow cover duration. In general, species richness is lower than 30 years ago. Many herbaceous species are rarefied or disappeared: in particular Caricetea curvulae and Nardo Callunetea species become reduced in abundance and number. On the other side, only few new species appeared ( e.g. Veratrum album, Maianthemum bifolium, etc.). Changes in vegetation features seem to be due in part to natural dynamics (lighter grazing) and in part to climatic stress. In fact, the climate of the area has become warmer and drier (less snow and less rainfalls in winter, spring and summer) over the last 2 decades, as deduced from data of Marletto et al., 2010 (Atlante idroclimatico dell’Emilia-Romagna 1961-2008. ARPA). Aridity periods (P/T<2), recently occurred in several summers, may be the main causal factor of the population declines in sensitive species; in fact, drought can affect the primary productivity, the reproductive success (most declining species are summer-flowering) and the survival rate.
Bonafede F., Puppi G., Ubaldi D., Vignodelli M., Zanotti A.L (2012). Vegetation changes during a 30 years period in several plant communities above the forest line (Emilian Apennines). PERUGIA : Università Di Perugia.
Vegetation changes during a 30 years period in several plant communities above the forest line (Emilian Apennines)
PUPPI, GIOVANNA;UBALDI, DAVIDE;ZANOTTI, ANNA LETIZIA
2012
Abstract
The study highlights the changes occurred in 10 homogeneous stands both of Vaccinium and Nardus communities of the Emilian Apennines after 30 years from the first surveys. The stands were sampled by phytosociological and phenological methods in the years 1981-1984 (Puppi, Zanotti & Speranza, 1994 - Phenological studies on Vaccinium and Nardus communities. Fitosociologia) near the mount “Corno alle Scale” (BO). In that time, the locations of the stands were exactly recorded (CRT map 1:10000) and documented by series of photos. In 2011 and 2012 the original sites were found again and the same types of surveys were repeated, with the aim to detect any change and to investigate its possible causes. Main results are here summarized. Community’s structure has become more complex: in particular, Juniperus nana cover is significantly increased; moreover, among Vaccinium species, V.gaultheriodes is going to prevail on V. myrtillus, probably damaged by the shortening of the snow cover duration. In general, species richness is lower than 30 years ago. Many herbaceous species are rarefied or disappeared: in particular Caricetea curvulae and Nardo Callunetea species become reduced in abundance and number. On the other side, only few new species appeared ( e.g. Veratrum album, Maianthemum bifolium, etc.). Changes in vegetation features seem to be due in part to natural dynamics (lighter grazing) and in part to climatic stress. In fact, the climate of the area has become warmer and drier (less snow and less rainfalls in winter, spring and summer) over the last 2 decades, as deduced from data of Marletto et al., 2010 (Atlante idroclimatico dell’Emilia-Romagna 1961-2008. ARPA). Aridity periods (P/T<2), recently occurred in several summers, may be the main causal factor of the population declines in sensitive species; in fact, drought can affect the primary productivity, the reproductive success (most declining species are summer-flowering) and the survival rate.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
