Synthesis of polymer intermediates containing the bicyclo[3.2.2]nonane ring
作者:Ludek Taimr、James G. Smith
DOI:10.1139/v70-201
日期:1970.4.15
The preparation of 1,5-biscarbethoxybicyclo[3.2.2]nonane and 1,5-bis(hydroxymethyl)bicyclo[3.2.2]nonane is described. The procedure generally followed that reported for the analogous bicyclo[2.2.2]...
High mountain psychro-xerophilous calcicolous pastures of the Iberian Peninsula:Minuartio-Poion ligulatae
作者:Julio Peñas、Javier Cabello、Francisco Valle、Juan F. Mota
DOI:10.1007/bf02899986
日期:2001.12
A syntaxonomical review of the Minuartio-Poion ligulatae (Festuco hystricis-Ononidetea striatae) in the Iberian Peninsula, supported by numerical classification (complete linkage clustering) and ordination (correspondence analysis), is presented. Communities of psychro-xerophilous calcicolous plants occur in the high mountains and "parameras" of the south and central western Iberian Peninsula, areas which suffer from severe frosts. The data collected point to three large groups of communities: those of the chorological Carpetano-lberico-Leonesa Province; those of the Castellano-Maestrazgo-Manchega Province; and those of the Mica Province. Within the latter group, similarities and differences between the communities were analyzed and two new associations (Herniario boissieri-Festucetum hystricis and Pimpinello gracilis-Festucetum nevadensis) were described. In addition, data clearly support the existence of a humidity-xericity gradient responsible for the distinction of the communities into different syntaxonomic units.