1,721,032 research outputs found
Il Parco Nazionale della ValGrande nell'ambito del progetto "Boschi vetusti nei parchi nazionali italiani"
No full textStria dei boschi del Parco nazionale della valGrande. Stato di fatto e dinamiche in atto. Definizione di "bosco vetusto" e nuclei "vetusti" individuat
Vegetazione "reale" e "potenziale": le serie dinamiche ed il ritorno del bosco perduto
No full textFormalizzazione e descrizione delle Serie dinamiche di vegetazione. Alcuni esempi per i boschi lombard
Inquadramento sintassonomico dei boschi di Ostrya carpinifolia Scop. delle Prealpi Lombarde
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Pioneer herbaceous vegetation on glacier forelands from the Italian Alps
No full textAbstract. The pioneer vegetation of the Holocene moraines of some Italian glaciers was
studied by a phytosociological approach. Particular attention was given to mid-successional
communities on stabilized terrains (19th century moraines). Sixty-seven releve ́s
were performed on the forelands of 8 glaciers from the central and western Italian Alps,
from continental inner alpine to oceanic prealpine areas. Early as well as late successional
stages were sampled. Releve ́s were analyzed by cluster analysis using the Jaccard index
and UPGMA as the clustering method.
Two main clusters could be separated: 1) pioneer, low cover communities of recent
and/or disturbed moraines; 2) high cover communities of already stabilized moraines,
mainly ice-free since the 19th century. The first group included the pioneer community
Sieversio-Oxyrietum digynae Friedel 1956, which can be divided into three subassociations:
typicum, androsacetosum alpinae subass. nov. and a subtype with Epilobium
fleischeri and Saxifraga aizoides. The second group includes species-rich coenoses
occurring on stable but gravel terrains, ascribed to the Saxifrago bryoidis-Poetum
alpinae ass. nov. (including subassociations trifolietosum pallescentis subass. nov.
and salicetosum retusae subass. nov.), and continuous grasslands dominated by Poa
alpina and Agrostis rupestris. The last type could be divided into a rankless Luzula alpinopilosa
community and a Trifolium pallescens grassland (Agrostio rupestris-Trifolietum
pallescentis ass. nov.). These plant communities are differentiated by many environmental
factors. Terrain age and related parameters seem to play the main role:
low-cover pioneer communities grow on 20th century deposits, whereas high-cover communities
occur mainly on already stabilized moraines dating back to the 19th century.
Altitude, aspect, insolation, morphology and parent material can also be determinant;
altitude should be taken into account considering the local context of the altitudinal belts,
which depends on the degree of continentality.
Although highly variable, the Sieversio-Oxyrietum digynae should not include
all the pioneer stages recorded from glacier forelands. This is supported by a synoptic
table based on our data and on published releve ́s from the Austrian, Swiss and Italian
Alps.
Keywords: Alpine Belt, Androsacion alpinae, primary succession, Sieversio-Oxyrietum
digynae
Filari nei paesaggi agricoli: variabili strutturali più influenti sul contenuto in specie erbacee nemorali indicatrici di qualità
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Boschi frammentati nei territori comasco, lecchese e milanese : problematiche fitosociologiche e stato di conservazione
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Serie dinamica del bosco a Rovere: il caso del Parco nazionale Val Grande (VCO)
No full textViene ricostruita la serie dinamica del bosco a rovere nel
Parco Nazionale Val Grande (VCO), quale caso di studio esportabile
a tutta l’area prealpina occidentale suboceanica, per analogia di clima
e substrato. Sono state cartografate, in ambiente GIS, le aree di pertinenza
della serie sulla base delle caratteristiche climatiche e fi siche del
territorio. Entro tali aree sono stati effettuati 48 rilievi fi tosociologici
che hanno compreso tutti gli stadi serali della vegetazione, per poi procedere
con l’analisi delle fi tocenosi individuate e la loro interpretazione
in chiave dinamica. Risultato dello studio è l’individuazione di sei fi -
tocenosi, quattro delle quali (pteridieti, calluneti, betuleti, rovereti) fra
loro collegate da un legame dinamico, suggerito da analisi fl oristiche
quali-quantitative sull’abbondanza delle specie e dall’analisi dei parametri
ecologico-stazionali tramite CCA.Ecological succession of sessile oak woods: Val Grande
National Park (Italian Western Alps) as a case study. We assessed the
ecological succession of sessile oak (Quercus petraea) woods in Val
Grande National Park (Verbano-Cusio-Ossola, Italian Western Alps), as
an example available for all the western prealpine insubric area. With
GIS we have deduced the map of the areas of pertinence of Quercus
petraea, based on climatic and physical characteristics of the territory.
Within these areas we carried out 48 phytosociological relevés according
to Braun-Blanquet method, assessing all stages of the ecological succession.
As a main result the Cluster Analysis individuated 6 phytocenoses
and 4 of the them (Pteridium aquilinum grasslands, Calluna vulgaris
moors, Betula pendula woods, Quercus petraea woods) have a dynamic
link suggested by quali-quantitative analysis about species ecology and
abundance and by several environmental parameters analyzed by CCA
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