Maria Speranza

A phylogeographic study of the cosmopolitan genus Phragmites (Poaceae) based on AFLPs

Within the genus Phragmites (Poaceae), the species P. australis (the common reed) is virtually cosmopolitan, and shows considerable variation in ploidy level and morphology. Genetic variation in Phragmites was studied using AFLPs, and analysed with parsimony and distance methods. Groups of P. australis strongly supported in the analyses include one that comprises all South American clones, a distinct group from the US Gulf Coast, and a group of E. Asian and Australian octoploids. Among the other species, the paleotropical P. vallatoria is supported as monophyletic and most closely related to the paraphyletic P. mauritianus and to the Gulf Coast and S. American groups. The E. Asian species P. japonicus is closely related to a group of P. australis clones mostly from central North America. Tetraploidy predominates in the genus, and optimisation of chromosome numbers onto the phylogeny shows that higher ploidy levels have evolved many times.

Natura 2000 Network: A Comparison of the Italian and Dutch Implementation Experiences

The implementation of Natura 2000, Ecological Network of protected areas established in the European territory under Council Directive 92/43/EEC, has encountered serious problems in many European States. This is proven by conspicuous juridical interventions initiated by the European Union against Member States failing to comply with the Directives requirements; by the aversion of stakeholders involved in the use of protected areas and by the criticisms that environmental non-governmental organizations expressed about the governmental approaches towards the networks realization. This paper presents a critical reflection on the problems in the realization of Natura 2000 Network, by analysing and comparing the experiences of two Member States: the Netherlands and Italy. Despite the differences in national natural heritages and nature conservation policy traditions, the two Natura 2000 implementation processes present interesting similarities. These allowed the authors to identify theoretical and practical obstacles that are making the networks implementation problematic and to reflect on the most important challenges to the realization of Natura 2000 Network in the two countries, as well as in other Member States that experienced similar implementation problems.

The genus Dactylis L. in Italy. 1. The tetraploid entities

Summary Dactylis L. is present in Italy with some diploid (2n = 14) entities and a broad complex of tetraploids (2n = 28). The latter are the large majority of Italian populations. A biometrical and biochemical analysis on herbarium material and on specimens sampled from natural populations, showed that the characters concerning size and shape of the inflorescence form a continuous series, are strongly correlated among themselves, but do not correlate with other characters. The presence and dimensions of lobes on the lemma is variable on the same specimens and is more frequent on the western side of the Apennines than on the eastern side. The presence of papillae and of a smooth margin on the leaves have a weak mutual correlation, are more frequent in western populations, and are exclusive of coastal stands. Other characters vary irregularly, and do not correlate with the characters above. Protein characters also present some differences among the samples studies, but do not correlate with morphological c...

Conservation and recreational values from semi-natural grasslands for visitors to two Italian parks

According to integrated natural resources management, interrelated resources have to be managed by maintaining their environmental quality, and visitors are stakeholders who have to be involved in natural park management decisions. In this paper we simultaneously examine the conservation and recreational values from grasslands for visitors to two Italian Regional Parks. A contingent valuation survey was carried out in 2007 for estimating non-use benefits to visitors from a grasslands conservation project in these parks. Two scenarios were considered: the present landscape composed of grasslands and forests, and a hypothetical scenario of forests without grasslands. Respondents were asked the quality rating of the parks as places for recreational activities, and their willingness to donate (WTD) per year to a project for maintaining the status quo. Results show that the majority of respondents give a high rating to these parks, are in favour of the project implementation, and willing to donate mainly for the benefit of future generations. Among the WTD determinants, by estimating a Tobit model and a two-stage model, giving a high quality rating to the park for recreational activities corresponds to a higher WTD for grassland conservation. This seems to suggest that the recreational motivation tends to coincide with the need to conserve habitats and biodiversity, and that the decision maker should pay specific attention to the maintenance of the quality of the recreational activities as well as the maintenance of a diversified landscape in these parks.

The genus Dactylis L. in Italy. 2. The diploid entities

Two diploid subspecies of Dactylis glomerata L. are recognized to be present in Italy. D. glomerata subsp. aschersoniana is present in mesic mixed broadleaved forests of Friuli (North-eastern Italy); its occurrence in other parts of the territory is questioned. D. glomerata subsp. reichenbachii is an endemic of Pinus sylvestris woods of Alto Adige. Furthermore, diploid individuals have been observed irregularly scattered through Northern Italy. Such individuals are morphologically very variable, and do not deserve a particular taxonomic treatment. Biological and evolutionary relationships within the species are discussed. An analytical key to the italian entities of Dactylis is given.

Genetic variation for aerenchyma and other root anatomical traits in durum wheat (Triticum durum Desf.)

Variation in root anatomical traits influences whole plant physiology and crop adaptation to adverse soil conditions and thus impacts yield and its stability. A typical component of anatomical root traits is the arrangement of cells and tissues as observed by microscopy sections. In this study, we investigated the phenotypic variation of 11 root anatomical traits including aerenchyma-like features in ten elite durum wheat cultivars and found significant differences among cultivars for several traits. Trait heritability ranged from 0.12 (number of xylem vessels) to 0.72 (number of aerenchyma-like lacunae). While area and number of aerenchyma-like lacunae were highly correlated, neither trait correlated with other root features, suggesting an independent physiological and/or genetic control in respect to the other root anatomical traits. The old Italian founder cultivar Cappelli was shown to have a significantly higher portion of root aerenchyma-like structures of all the modern cultivars. These results show for the first time the presence of sizeable genetic variation in root anatomical traits in cultivated tetraploid wheats, prompting for additional studies aimed at mapping the quantitative trait loci governing such variation and to test their role in the adaptive response of durum wheat to abiotic stresses as related to soil conditions.

Land use transformations, territory naturalness and ecological planning

An analysis is made of the land use transformations over the last sixty years, as well as the consequences of these transformations on the naturalness of the territories of three municipalities of the “Nuovo Circondario Imolese” (Bologna, Italy). The selected municipalities are: Medicina, Borgo Tossignano and Castel del Rio, which represent the main territorial aspects of the “Nuovo Circondario Imolese”.The land use transformations are quantified through the GIS comparison of the land use maps of the years 1995, 1976, 1994 and 2003. The corresponding legends are transformed into the five categories of the first level CORINE Land Cover classes. The naturalness increases in the three territories throughout the period 1955-2003, but with different quantitative importance: limited for the territory of Medicina and progressively increasing from Borgo Tossignano to Castel del Rio. Urban areas increase too, but following a gradient opposite to the one concerning naturalness. The land use transformations in the “Nuovo circondario imolese” are similar to the trends reported for the same period in Italy as a whole and in many other European countries. Concerning the effects of land use transformations on the territory naturalness and biodiversity, our results highlight the critical state of the intensively used areas and the marginal areas. Some lines of action for a correct ecological planning of these different situations are suggested.

Numerical studies of compositional gradients in oreophilous vegetation (northern Apennines, Italy)

A numerical study of a set of phytosociological data from oreophilous vegetation in the Apennines (Italy) has been performed. Ranking, classification and ordination methods have been used. The advantages of the joint use of the different methods is diseussed. The results confirm a compositional gradient related to degradation due to grazing, and another, related to base-richness in the soil. Compositional variation does not appear strongly disjointed.