The non-native vascular flora of Campania (southern Italy)

We discuss several aspects of the alien flora of Campania (southern Italy), on the basis of an updated and annotated checklist. The non-native flora includes at present 346 taxa in 231 genera, representing 82 families. However, other 55 taxa were not found later than 1950. Trends in alien plants invasion throughout the investigated area are discussed. Results are therefore compared with similar data from other Italian regions and other European countries. In the Appendix, taxa are listed with essential synonymy, local and general distribution, status, biological form, habitat, diffusion mechanisms, potential threats, literature data, voucher specimens, and miscellaneous ethnobotanical, chronological and taxonomical notes. In addition, 49 escaped taxa are known only for Botanical and private gardens, while 66 taxa are regarded as doubtful aliens. By including also these two categories, the non-native flora of Campania reaches 516 taxa. In addition, numerous doubtful and erroneous indications were discussed. Finally, a reference list for the exotic regional flora from 1500 C.E. to present is proposed.     

Identity and taxonomic affinity of some members of the Amaranthaceae from the Galápagos Islands

ELIASSON, U. H. 1985. Identity and taxonomic affinity of some members of the Amaranthaceae from the Galápagos Islands. The type species of Pleuropetalum, P. DarwiniI, is endemic to the Galápagos and is morphologically closer to P. pleiogynum than to P. sprucei. Pleuropetalum pleiogynum has a wider distribution than previously assumed, ranging from Costa Rica to Peru. Amaranlhus anderssonii is closely related to A. urceolatus, a species of the Pacific coast of S America, and to A. berlandieri, a species of Texas and NE Mexico. Amaranlhus squamulatus, previously regarded as endemic to the Galápagos, is reported from the Guayas province of Ecuador. The genus Galápagosus, proposed for Amaranlhus sclerantoides, is rejected. Lithophila scirpoides, an overlooked taxon from the Galápagos, is believed to be an aberrant specimen of L. radicala. Lithophila subscaposa from the islands of Santiago and Pinzon differs morphologically from the specimens of Floreana. Iresine edmonstonii, probably erroneously reported from the Galápagos, is conspecific with J. angusti/olia. Blutaparon rigidum is morphologically divergent from other members of the genus, being adapted to arid conditions, and is assumed to be extinct.     

Secondary dune succession on Inhaca Island,Mozambique

Old field succession was studied on coastal dunes supporting tropical evergreen forest on Inhaca Island, Mozambique. Plots of 10×10 m were sited in three early successional stages and in relatively undisturbed forest. Woody species increased in number during succession; leptophylls were most frequent in younger vegetation, whereas microphylls and mesophylls were most frequent in forest. Grasses, shrubs and forbs dominated initially following abandonment, and shrubs persisted as dominants in the three early successional stages. The initial floristic composition model was generally supported by the pattern of species sequences, with many forest species entering early in the succession. Of the few species conforming to the relay floristic model, many were grasses and forbs of the forest understorey. Similarity between plots of equivalent vegetation age indicated that, at least in early succession, there was linearity in the successional pathway; there was no evidence for divergence or multiple pathways. In early succession, no accumulation was detected in either soil organic matter or extractable nutrients, thus providing little support for the facilitation model of succession. It is stressed that the findings are probably scale-dependent.     

惠州西湖风景名胜区维管植物资源与多样性研究

为了明确惠州西湖风景名胜区维管植物资源及多样性特征,该研究通过野外实地调查和文献查阅,统计惠州西湖风景名胜区维管植物种类构成及其科、属、种层面的具体组成,并分析其分布区类型、濒危物种、药用植物和水生植物状况。结果表明:(1)惠州西湖风景名胜区共有维管植物169科650属1 061种,其中被子植物种类最丰富,有145科613属1 002种,科、属、种数分别占总数的85.80%、94.30%、94.44%;裸子植物9科20属36种,科、属、种数分别占总数的5.33%、3.10%、3.39%;蕨类植物15科17属23种,科、属和种数分别占总数的8.88%、2.60%、2.17%。(2)惠州西湖风景名胜区植物资源的优势科明显,含10种及以上的科有29科653种,占总种数的61.55%,其中菊科最多(有63种),禾本科次之(有60种);研究区有单属、种的植物442种,表明单种或少数种的科在研究区维管植物中占大多数。(3)惠州西湖风景名胜区有种子植物154科,分属13个分布区类型,其中泛热带分布区类型有60科,所占的比例最高(55.56%),表明该区种子植物具有明显的热带特性,其种子植物区系以热带分布为主。(4)惠州西湖风景名胜区有珍稀濒危植物29种(其中国家保护植物26种),药用植物702种,水生植物150种。研究表明,惠州西湖风景名胜区维管植物资源种类丰富,多样性程度高,应特别加强植物资源的保护和利用以及生态景观的建设。     

Effects of fire frequency on plant species composition of sandstone communities in the Sydney region: Combinations of inter-fire intervals

Abstract Fire frequency is the number of fires experienced by a particular community within a given time period. This variable can potentially be resolved into a number of interacting components, including time since the most recent fire, and the length of the inter-fire intervals. We estimated the effects of inter-fire intervals and sequences of inter-fire intervals, independently of time-since-fire, on the floristic composition of 26 samples from dry sclerophyll vegetation with different fire histories in Brisbane Water National Park near Sydney. In particular, we examined the effects in the recent fire history of: the length of the shortest inter-fire interval (1–26 years); repetition of very short (1–3 years) and medium (7–14 years) inter-fire intervals; and recovery from very short (1–3 years) and short (4–6 years) inter-fire intervals. Our analyses suggest that inter-fire interval may account for about 55% of the floristic variation among our samples, which were taken at a uniform 18 months after the most recent fire. There appear to be at least three general and unrelated effects of the recent history of inter-fire intervals on the floristic composition of this vegetation: (i) shorter inter-fire intervals were associated with a reduction in the number of species present in the community, along with a more unequal abundance of the remaining species, particularly of those large Proteaceae shrubs that often dominate the community biomass in dry sclerophyll shrublands of southeastern Australia; (ii) the presence of an inter-fire interval that is 1–6 years long was associated with an additional reversible reduction in the number of fire-sensitive species present in the community, particularly those common shrub species with a canopy-stored seed-bank and non-leguminous species with a soil-stored seed-bank; and (iii) repetition of inter-fire intervals that are 1–5 years long was associated with an increase in the abundance of herbaceous fire-tolerant species. This means that variation in these characteristics is associated with changes in abundance of different plant species, and that the floristic composition of any one area can be influenced in three different ways by these variables. Management of fire for plant species conservation must therefore be based on both length of time-since-fire and length of inter-fire intervals if it is to be effective.     

湖南猕猴桃属植物地理分布及其区系特点研究

湖南猕猴桃属植物有２１种１３变种,主要分布于湘南和湘西两地区,经分析研究,湖南猕猴桃属植物区系有如下特点：１、种类比较丰富,是构成湖南森林植物区系林间植物的主要成分之一;２、地理成分比较复杂,种的分析显示出以中国特有分布为主的特点;３、种间、种内分化强烈;４、特有种较多;５、与邻近地区猕猴桃属植物区系的关系密切,最后,作者对湖南猕猴桃属植物的起源问题进行了分析和推测。     

浙江武义木本植物区系的研究

武义位于浙江中西部,共有木本植物９２科２６８属６８０种,本文对该区木本植物的科、属、种进行了详细的分析统计,将该区木本植物区系的基本特点归纳如下,１）植物种类丰富;２）古老和孑遗植物,珍稀植物,单型属和少型属较多;３）各类地理成分复杂,与世界各地联系广泛,以温带成分为主;４）区系过渡性明显。     

浙江天台山七子花群落特征的初步研究

天台山的七子花林,常见的种子植物有１２５种,隶属５１科,１０２属。其中热带类型３６属,温带类型５２属。按Ｒａｕｎｋｉａｅｒ生活型统计,高位芽植物占７０．８％,地面芽植物占２２．３％,地下芽植物占４．６％,一年生植物占２．３％,高位芽植物的比例与本省常绿落叶阔叶混交林的生活型谱近似。叶级以小型叶为主,占５３．１％。叶型以单叶比例最大,占７８．５％。群落结构可分为乔木层、灌木层、草本层和地被层。