Table of Contents

This is an attempt to characterise the Mediterranean region in biogeographic-historic terms, and not the usual climatic ones. "Mediterraneis "is a province contained between the Sahara and the Alpine mountain ridges, with the Mediterranean Sea, the only remnant ofthe Mesozoic Tethys as its core. The fauna and flora of the province is composed of Palearctic and some Ethiopian biota which evolved during the late Neogene, in the refuges of the sea shore and on the many islands. There has been a tight relation with the hydrological evolution of the Mediterranean sea, culminating with the paroxysm of the Messinian event. Information on floristics and faunistics is being compared. Characteristically foro this province, ear1y seafaring co-existed already with post-Glacial climate fluctuations and tectonic conflagrations Peculiar circumMediterranean distribution areas resulted from prolonged human impact. Cycles of frequent and sudden altemations of humid to arid climates, jointly with the anthropic impact moulded this province. The modem Suez Canal and river-damming have al so radically changed marine life.

Definition ofthe Mediterranean ecosystem based on climate, characterized by an arid peri od in sllmmer. Main composition of the flora and relationships with the fl ora of the region with Mediterranean type vegetation in W.AlIstralia. Adaptations to fire. Man - Vegetation relationships: Man as a factor of evollltion - Vegetation as food reserve. Coevollltion. Weeds of Mediterranean origin invading other continents.

Monte Pisano includes a group of hills spreading from NW to SE between the Lucca and Pisa plains in NW Tuscany, Centrai ltaly. In spite of its modest height (max . 9 17 m a.s.l.) and size (20 x IO km), Monte Pisano shows a rugged morphology with numerous peacks, va lIeys, siopes and piains, springs and streams. Its geological history, Iinked to that one of the Apuan Alps, dates back to Palaeozoic era. A wide variety oflithological types, stones ("verruca no" and Saint Giuliano "marble" were used to build the medieval Lucca and Pisa towns), substrates and habitats is offered to visitors, as well as numerous aspects of the anthropic history, i.e. ancient settlements, casti es, fortresses, villas and churches remains. During last decades fieid investigations carried out by many researchers of Pisa University enlarged the knowledge of several naturalistic aspects ofMonte Pisano, includind the geobotanical ones. Special attention was recentIy payed to the pteridology of the area. The main result of these investigations may be summarized as follows. Nine species previously documented in PI, FI, SIENA and other Herbaria may be considered as extinct for the area. Among them, Hymenophyllum tunbrigense, Phegopteris connectilis, Marsilea quadrifolia, Sa/vinia na/ans. The presence of Dryop/eris oreades is confirmed, together with those of Oreopteris limbosperma, Cheilantes tinaei, Asp/enium foreziense and çJphiog/ossum azoricum. A decaploid cytotype (2n= 11 O) of lsoetes duriei w...

HackeI's Monographia Festucarum Europaearum (1882) can be considered the starting point of modem systemati c studies on this criticaI genus in Europe. After his work, almost one hundred years of infonnation was summed up by Markgraf-Dannenberg (1980) in her treatment of the genus in Flora Europaea. Here, the total number of species had increased from 28 (Hacke1 (882) to 170. However, this was due more to the raising to the rank of species of many infraspecific taxa, than to the recognition of new enti ti es as a result of taxonomic investigations. During these hundred years, the increase of knowledge on the systematic of this genus was very unequal in different European countries: in some of them like France, many in-depth investigations were carried out, while in other countries Iike Italy, studies started Iater and were much Iess exhausti ve. Our research team has been carrying out taxonomic investigations on the genus Festuca in Italy for several years, making use of modem systematic tooIs, among which typification and study of type material play an important role. In many instances, the results of our researches Ied to remarkable taxonomic rearrangements within criticaI groups. Some examples are illustrated, conceming the F violacea group, the endemic F robustifolia, and the relations between F gracilior and F inops.

The paper describes and critically analyses the distribution in Sardinia of the species of the genus Quercus L., their main morphological, biological and ecological traits. Particular emphasis is addressed toward the Q. pubescens Willd. s.l. complex and toward the evergreen Q. coccifera L. s.l., aiming to highlight the great variability of ali traits, as well known from the literature conceming other oak populations of diverse geographical regions.

On trouvera ici une sélection de 26 espèces ligneuses cultivées comme plantes ornementales dans le nord-est de la Péninsule Ibérique et représentatives des cinq continents. Certaines sont très abondantes (Platanus xacerifolia, Celtis australis), tandis que pour d' autres on ne dénombre que peu d'exemplaires cultivés (Erythrinafalcata, E. lysistemon). Bien que le climat soit méditerranéen il existe d' importantes variations climatiques ce qui conditionne mais aussi diversifie le catalogue des espèces à utiliser. On cultive aussi bien des espèces indigènes qu 'exotiques. La grande majorité des espèces sélectionnées ici ont une origine exotique, bien que, actuellement elles sont très communes pour nous. La flore ornementale du nord-est de la Péninsule Ibérique est très riche et variée, et comprend plus de 600 espèces ligneuses, qui permettent d'orner les différentes situations d' une façon très diversifiée, en jouant sur les différentes formes, coul eurs, textures, floraisons, parfums, etc.

First data on the adventive plants in Serbia date from XIX century, but the intensive studies begin in the lasl fifty years. At the beginning the records of new ad venti ve species were commented as one way of enriching flora. It was, however, noted that some species spread sub spontaneously, and rarely even spontaneously, but that was not considered very important. Today, when we know how important it is to preserve the natural diversity ofthe autochthonous flora and vegetation, the presence of the adventive plants must be considered to be a threatening factor. As a rule, these plants come from the remote biogeographic areas, -and in the new habitats have neither natura I enemies nor competition. They mostly have the low ecological requirements and the high level of ability to adjust. Some of these species spread very aggressively, especially in areas where the natural vegetation is disturbed or destroyed, and habitats devastated. By occupying that space, they disable the natural reversible processes of the autochthonous flora. After they enter the natural vegetation, they cause the relationship changes within communities, and lead to the serious disturbance ofthe natural succession. Factor ofthe introduction and further spreading of the adventive plants, both direct and indirect, is always anthropogenous. The urban and periurban areas, where the anthropogenous influence is most intensive and diverse, are the real "nurseries" ofthe adventive plants. From these ha...

This study aims to analyse the role played by some physiographic and ecologic variables such as area, isolation, altitude and substratum type on the bryophyte species richness of 49 small ltalian islands. Both floristic similarity between islands and bryophyte species richness depend above ali on the island size. The other variables, i.e. the prox imity to the c10sest continent or major island, the distance between islands and the type of substratum, account for only small differences between the island bryofloras. Unexpectedly, the number of bryophyte species in these islands is not negatively related to the distance fTom the continent. This outcome is due to the confounding effect of island size and age, as well as to the stronger human impact that is likely to occur in close-to-eontinent islands. The high slope of the speeies-area curve indieates a very scarce bryophyte immigration, even trom the closest islands. The low dispersion ability is partly related to some life history traits of the xerophilous mosses. The only two endemi e species (Rhynchoslegium strongylense and Thamnobryum cossyrense) that oeeur in no more than five islands were not suffiei ent to test whether the isolati on from the eontinent has favoured the differentiation of new species. The outeome of the analyses performed refleets the current bryo-chorological knowledge coneerning the small Italian islands, and thus it is likely that reports of new species could change some bryogeograp...

The results of a recent bryophyte collection from Cyprus in 1997 are presented and discussed. 24 bryophytes are reported new to the island, including Petalophyllum ralfsii, Aschisma carniolicum, Syntrichia minor, Gigaspermum mouretii, Orthotrichum acuminatum and O. tortidontium.

This research has been carri ed out to provide an evaluation ofthe bryophyte diversity ofSicilian urban areas. For this purpose, the bryophyte flora of the coastal towns of Agrigento and Siracusa (S and SE Sicily, respectively) was studied. These data has been analysed together with those of the towns of Enna (C Sicily), Catania (E Sicily) and Palermo (N Sicily), published previously. The bryophyte flora of Sicilian urban areas has also been compared to other Italian and Spanish ones. A database with chorological, ecological and biological data has been set up and a cluster analysis has been carri ed out. The results show that the urban bryoflora is rich and diversified in Sicily. Besides a high number of taxa, it is characterized by a high number of urbaniphilous taxa, a higher value of hepatics/mosses ratio, and, from a chorological point of view, by lower and higher incidence of temperate and oceanic-Mediterranean taxa respectively, than that of the other considered cities. Although the presence of green areas and of poorly disturbed habitats greatly affects species diversity, geographical and climatic factors mainly influence bryoflora composition and richnesso

Recent bryologica l research in Egypt, resulted in a relllarkabie eni argelllent of our knowledge about the IllOSS flora o r this country which constitutes part o r Arr I and part of As 5. The distribution of the 175 IllOSS taxa, hithelto, repolted frolll Egypl, .in the world, indicates the existence of various bryofloristi c elelllents reAecting the di versity or the flora. The 175 taxa represent 145 species be longing to 45 genera, 14 fal11ili es and nine orders; al i under class Bryopsida and ali are reported l'rolll 12 oul or the 15 phytogeographical terrilori es lo whi ch the country is di vided. References to vari alions in Aoristic aspects of IllOSS flora s o r studied phylogeographic territories as we ll as lO paral11 eters be li eved to be responsibl e 10 1' these variations are l11ade.

One of the expeeted eonsequences of global change (due to elimatie ehange or to human aetivities, such as ehanges in land use) is the fragmentation of plant populations in small and isolated units moresuitable to disappear beeause the possibilities of gene fiow are interrupted and the redueed number of individua1s is not enough to faee environmental, genetie or demographie stoehastie events. These effeets are expeeted to be higher in rare or endemie speeies with a Iimited distribution, sinee these organisms are more sensitive to this kind of ehanges. In the present work, we studied the effeets of fragmentation of populations in three endemie plants from the Mediterranean region: Delphinium bolosii (Ranunculaceae), Pelrocoplis monlsicciana (Caryophyllaceae) and Seselifarrenyi (Apiaceae). They are threatened plants and proteeted by law. They also have different degree offioral complexity and different degree ofpollinator speeialization. We analyzed the effeets offragmentation using eomparisons ofpairs ofpopulations (Iarge-small) at two levels: the reproduetive sueeess (measured through pollinator visitation rates, quantity and quality of pollination services and seed set) and the parameters of genetic diversity (using allozyme eleetrophoresis). Results ofthis study will allow postulate bases for the management and eonservation ofthese speeies.

The relevance of spatiall y explicit studies of genetie diversity in threatened taxa along with the importance of understanding that biologica I proccesses and environmental factors that determine the genetic structure is examplified in the study case of Antirrhinum microphyllum Rothm. (Scrophulariaceae) an endangered narrow endemie ofCentral Spain. The approaeh al a regional scale including ali known populations was based in allozyme analysis of 184 individuals (46 individuals per population) and showed little differentiation among populations. [n a second step Bolarque population was approaehed through RAPO analysis. The study showed that the population was genetically structured in neighborhoods. Pollen transport may be responsible far the maintenance of geneti c vicinities whereas sporadic long-distance seed dispersal is IikeIy to explain the relatedness among certain patches. Ali these features carry aut important implications far conservation.

Current distributions of many European plants are reduced to a mosaic of small isolated populations which have to face the demographic and genetic consequences ofhabitat fragmentation. Apart from environmental and demographic stochasticity, inbreeding depression is considered as an important fa et or determining extinction risks offragmented plant populations. Despite the important theoretical background rega rding the evolutionary dynamics of inbreeding, there is a considerable lack of empirical data to understand how real plant populations respond to inbreeding. In this paper, we suggest that individuai-leve I va riati on in inbreeding depression may play a significant role in decreasing extinction probabi lities of fragmented plant populations, as not ali individuals within a population can be negatively affected by inbreeding depression . We present an overview about conservation genetics, paying special attention to the theoretical significance of family-Ievel variation in inbreeding depression for plant conservation biology. We illustrate theory with preliminary resu lts oftwo ongoing research projects focusing on the conse rvation of plant species in fragmented habitats.

The surface of the Mediterranean Sea represents only a small percentage (0.8%) of World Ocean surface; but the biodiversity is paradoxically rather high (12%). Both biodiversity and structure ofbenthic assembl ages are reall y reduced proceeding l'rom west to east. The low va lues or biodiversity occurring in the eastern basi n are Iinked lO severa I factors among which microplates tectonic, paleoclimatic and meteorological evenls and especiall y geodynamic events or South Aegean Illicroplate, Sapropel Crises occurred during last 30,000 years, Indian Illonsoon depending clilllate in the easte rn basin and in the Ni le Oood, opening Bosphorus Straits during Pleistocene and Holocene and excavating of Suez Canal just a century and half ago.

Most taxonomists have moved to systematics in our days, but this does not apply for the Mediterranean workers who stili are confronted with the inheritance of a large number of poorIy known taxa and a complex flora that inc1udes elements of several different origins. The first task will keep its byzantine status as long as no serious attempt is made to catalogue the literature published in some ten languages and start the typification of the hundreds of val id names described since the Linnean periodo The second task, to identify and circumscribe the taxa, necessitates a broad comparative approach that local workers have only recently realised. The taxonomy of red algae, having its roots in the Mediterranean and being mainly based on features of the gonimoblast development and the presence/absence of an auxiliary cell, as originally founded by Schmitz and Oltmanns and later refined by Kylin and his students, remains a challenge. While molecular systematics straggle to guide us in the complex world ofthese over a billion years old organisms, our understanding of taxon relationships will remain based on structural diversity for many years to come. Such data range from thallus morphology and reproduction to ultrastructure of cell components. We need to enrich and update this enormous bank of information continuously, applying modern technologies but also keeping the Linnean c1assification system that has prove n efficient and on which taxonomy relies upon.

At present the taxonomy of Phaeophyceae is based not only on morphological characters, but also in uItrastructural and biochemical characters and in molecular data. Although molecular techniques have allowed us to clariry the taxonomy of brown algae, many problems remain unresolved. The main changes that the taxonomy of Phaeophyceae has undergone in recent years, particularly conceming Mediterranean taxa, and the problems that remain without solution are presented.

A présent peu de travaux sont consacrés aux algues rouges calcaires (Corallinales, Rhodophytes) des mers italiennes. Pour la plupart il s'agit de signalisations tloristiques, concentrées là où ces espèces sont les plus fréquentes. Les espèces recensées sont au nombre de 54, elles appartiennent à 2 familles (Corallinaceae et Sporolithaceae), à 6 sous-familles (Corallinoideae, Austrolithoideae, Choreonematoideae, Lithophylloideae, Mastophoroideae, Melobesioideae) et à 18 genres. D'un point de vue phytogéographique, on peut noter que la distribution de Corallinales dans les mers italiennes n'est pas homogène, car il y a un certain nombre d'espèces plus présentes que d'autres, probablement plus connues ou faciles à recueillir, com me d'autre part il y a un certain nombre de mers italiennes qui semblent plus ou moins riches d'espèces. 22% des attributions chorologiques ont été ici mis àjour en fonction d'une information de plus en plus rapide et pandémique, qui exige globalement plus d'attention. En fonction de la distribution spatiale, géographique (globale) et de la bathymétrie, ainsi que de la distribution temporelle et de leur présence dans la nature pendant plusieurs années (vivantes), décennies, siècles ou ères (fossiles) les Corallinales peuvent représenter un instrument naturel utile pour l'enregistrement des changements environnementaux aujourd'hui plus que jamais actuels (global change), tels de véritables "indicateurs biologiques". On justifie ainsi la m...

Both floristic and geobotanic characteristics of the benthic macroalgal flora of Italy are discussed. The flora, obtained from Iiterature records since 1950, consists of 869 (510 Rhodophyta, 205 Phaeophyta and 154 Chlorophyta) taxa accepted under current taxonomy. Ceramiales, Fucophyceae and Chlorophyceae of such a flora were separately compared with corresponding taxonomic lists of the following Mediterranean regions: Spain; France; Greece and Turkey; Libya, Egypt and Levant States (Syria, Lebanon and Israel); Morocco, Algeria and Tunisia. From that comparison it appears that the benthic macroalgal flora of the Italian coast is the richest in species, probably because it was the most studied especially in the last years. Hierarchical c1ustering of the above lists based on both floristic and phytogeographic characteristics were carried out and the results were expressed in dendrograms from which a noti ceable floristic similarity among the lists can be drawn since the lists are Iinked above the 50% level of importance excepting those of the Libya, Egypt and Levant States (30 to 50%), which could represent a floristic discontinuity. However, such a discontinuity, due to the low number of species recorded in that area, could depend besides on the insufficient floristic knowledge, on both geomorphologic characteristics of coast and paleoclimatic events like sapropel crises. But, from dendrograms based on chorological spectra, it results a more marked degree of simila...

The Tuscan Archipelago, with its seven main islands, is one of the most interesting areas in the northern Tyrrhenian Sea from the naturalistic point ofview. Botanical studies ofthis area began in the XIX century; in particular, the intensive floristic work of Sommier pointed out the high floristic diversity ofthe Archipelago. The level of insularity varies from island to island, especially in relation to the paleogeographic history of the region as a whole. The past and present role played by human activity in this area of study has influenced floristic and vegetational dynamics, so this aspect is one of the most important fields of interest. A revision of the flora of each island proved necessary for the purpose of conservation, especially after the consti tution of the National Park of the Tuscan Archipelago in 1996. Our floristic researches are based on field investigations and on the revision of originai collections housed in FI, plus all the ava ilab le bibliography. The floristic diversity for each island is reported in relation to morphological, ecological and chorological aspects. In particular, the floristic relationships with the CorsoSardinian sector and the Tuscan mainland area are examined, together with the role of endemics. This study is only the first part of a study on botanical aspects of the Tuscan Archipelago, currently in progress at the University of Florence.

The area known as 'Cilento' is located in southern Italy, south of Salerno, on the west (Tyrrhenian) coast of the peninsula. Knowledge of its flora has always been very scanty. A review on the available knowledge from the first studi es by Tenore (about 1810-1840) up to the year 2000 has shown how the information has changed during two centuries and what can be its future developments. ln particular, it is worth mentioning that at the time when Tenore published his researches, the number of vascular plant species Iisted for the Cilento was 444, whereas Lacaita, in a catalogue published in 1921 , recorded for this area 934 different species. To date the number of spontaneous (or naturalized) vascular plant species mentioned for the Cilento is 1940, with the assumption that this figure is going to increase in the near future following the floristic research presently carri ed out in the area.However, it is remarkable how 91 species among those mentioned by Tenore have no longer been found since 1850; it is reasonable to think that many of these are actually vanished, since typical of areas (such as sandy coastal dunes, humid areas) heavily modified by the human impact during the past 100 years.The study of the Cilento flora deserves, with no doubt, an adequate investigation, since this area, because of its typical geographical position and its litological and geomorphological variety, served as a hinge in the diffusion of species between the north and the south of l...

In agreement with other authors, Ornithogalum L. is considered as a distinct genus in respect to Honorius S. F. Gray and Loncomelos Raf. Accordingly, the ltalian taxa of Ornithogalum s. str. are here listed and briefly commented in a frame of their classical morphological and karyological characters. o. umbellalum L. is represented by different polyploid cytotypes ( 2n= 27, 36, 45, 54, 90 and 108, with or without B chromosomes). Doubts about the possibility to discriminate o. vulgare Sailer in such a variable complex are expressed. o. divergens Boreau (2n=54 + B), o. orthophyllum Ten. (2n=I8), o. exscapum Ten. (2n=I8) and o. ambiguum Terracciano (2n= I8) are probably in relation with o. corsicum Jordan & Fourr. (2n=18). o. adalgisae Groves (2n=45, 54), o. refractum Kit. (2n=54) and O. brulium Terracciano (2n=36, 45,54 + B, 72) constitute a group ofunits whose affinity and distribution must be further evaIuated. o. kochii ParI. (2n=I8 + B), looks very similar to o. monticolum Jordan. & Foun·. (2n=20). o. collinum Guss. (2n=18), according with our records, is present only in Sicily. o. comosum L. (2n=18), belonging to sect. Obtusangula Zahar., is distributed from north-eastem Italy to Sicily. o. monlanum Cyr. (2n= 18 + B), the only representative of subgen. Oreogalum (Zahar.) Tomadore & Garbari, is present from southem Italy to Sicily. o. gussonei Ten. (2n=14

• B) of subgen. Hypogaeum Zahar. grows in Apulia and Sicily. A new specific unit will be described for some...

The Mediterranean region houses ssome 25-30000 species of vascular plants and the herbarium collections that have been made of this flora are widely scattered not only in institutions within the region but important collections may be found in herbaria in non-Mediterranean Europe and other parts of the world, reflecting the range of botanists who have been involved in the study of the flora of this area. These herbaria range trom major world class institutions with severa I million specimens to small barely adeguate collections of the local flora. Most floristic work is undertaken today on a national basis and it is a mater of concern that National herbaria in several countries of the region are small and poorly supported. On the other hand, much of the floristic exploration and taxonomic studies on Mediterranean plants has been carri ed out by botanists foreign to the region, both professional and amateur. AIso, a number of major Floras has been written by botanists from outside the country concerned and the collections on which they are based are also largely housed outside the Mediterranean region. Conseguently much ofthe type materia I is to be found in other countries. The significance and implications of this historical inheritance will be considered and suggestions made for remedial action.

The collections made by George E. Post (and containing many ofhis type specimens) were augmented by Mrs W. S. Edgecombe with local Lebanese ones and together form the majority of the herbarium of the American University of Beirut. These have remained in the sequence of the second edition of Post's Flora in a locked room, somewhat unavailable. Recently, considerable attention has been given to this collection and work is in progress to make the collection of use to statI, students and visitors. The types are being located, scanned and placed in protective folders. Recent collections made by the ongoing U.K. Darwin lnitiative for the Survival of Species are being added. The nomenclature used is gradually being brought up-to-date.

This study fumishes a synthetic picture of the typus materia I held in the Herbarium centrale Italicum (H. C. I.) and particularly on those of Mediterranean origin collected in Italy. This material has been analysed for rank, geographical distribution, chorological and biological categories. The results have been put in relation with originaI collections and with their history (chronology, collectors and donors).

Most ofprevious plant collecting and floristic studies were carried out by foreigners. The resulting collections including type specimens are housed in herbaria abroad. Moreover, they are in many instances difficult to use by researchers on the Moroccan flora.During the last two decades active plant collecting expeditions have taken piace in the- major regions of Morocco, leaded by IAV in conjunction with other national and foreign institutions.The creation of a Botanic Garden (BG) at IAV has stimulated further dry and living collections for ex-situ conservation of rare and endangered plants that are of actual or potential economie value or of interest from medicinal or nutritional aspects. These joined efforts have resulted in the collec- . tion of thousands of herbarium specimens and over 700 living plants for the Botanic Garden. Thus, the IAV herbarium has joined lndex Herbariorum community and the BG has become a model for ex-situ conservation of endangered plants in North Africa and the Arab world. lt is also meant to play a leading role in the country in the field of environmental education through its newly built Environmental Education Centre

The biodiversity of the Sicilian plant heritage is examined as far as the occurrence of the cultivated plants of agricultural interest in ancient collections and illustrations is concerned. With this aim, collections dating back to XVIII and XIX centuries are taken into account, starting from the foundation of the Prince of Cattolica botanical garden, in 1690. The features of this heritage and their consistence with the past are considered referring to Arabian-Norman and previous times. Finally, the value of ancient collections in the agricultural heritage finding and conservation is examined.

The representation of habitats against axes of relative stress and relative disruption of growth opportunities, as conceived by Southwood and by Grime, provide helpful templates to which organisms may be fitted according to their abilities to cope with the habitat constraints. More than that, the template may be developed as a kind of"filter", whose porosity is set by the habitat, and the species whose traits allow them to pass the filter will be candidate components of the community structures likely to emerge.

Cyanoprokaryotes have had a chance to colonise almost ali biotopes over the biosphere during their long existence from early Precambrian till present time, without lost of their vitality and diversity. Their evolution is a continuai and rapid process of adaptation to changing environmental conditions, but in the range of the certain cyanobacterial genetic and structural pattern. As a consequence ofthis process, numerous genotypes and morphotypes (morphospecies) ari se, which are strictly ecological delimited. In principle, they did not were found any ubiquitous species within cyanobacteria. The cosmopolitan species exist, but only these ones, which are ecologically connected with corresponding cosmopolitan distributed biotopes (saline coastal swamps, eutrophic freshwater reservoirs, soil biotopes, etc.). And, of course, numerous species exist restricted in specialised and extreme biotopes and endemie in various local biotopes with specific conditions. - Numerous ecological types of cyanobacterial microflora are present in Mediterranean region. Cosmopolitan and wide-spread species occur particularly in plankton of eutrophic reservoirs and in soils. Special cyanobacterial assemblages are present in other habitats (sometimes microhabitats). Marine calcareous coasts (with endolithic types), saline and minerai inland waters (sometimes hypersaline localities), deserts, calcareous subaerophytic and wetted rocks, and volcanic substrates (wetted vo1canic rocks, vo1canic l...

This report provides a summary of the current knowledge about the species composition of freshwater phytoplankton assemblages in the major man made and natural lakes of Sicily. The development of freshwater phytoplankton studi es in Sicily starts in 1979 and is carried out on 33 water bodies. The distribution of the major taxonomic groups (Cyanophyceae, Chlorophyceae, Trebouxiophyceae, Ulvophyceae, Charophyceae, Chrysophyceae, Synurophyceae, Tribophyceae, Bacillariophyceae, Dinophyceae, Euglenophyceae, Cryptophyceae) and the frequency of the most important taxa are reported. Blooming and uncommon species are highlighted. Moreover, the chlorophyte Botryococcus terribilis, the cyanophyte Microcystis panniformis, and the tribophyte Pseudostaurastrum limneticum are recorded for the first time in Italy.

A brief review is carri ed out of the most common or interesting macroscopic and microscopic benthic algae occurring in Italian rivers, in particular those inhabiting the centrai Apennine watercourses. They be long above ali the following classes: Cyanophyceae (Cyanoprokariota), Chrysophyceae, Xanthophyceae, Bacillariophyceae, Rhodophyceae, Chlorophyceae, Zygophyceae and Charophyceae. All the algae of the running waters, thanks to their sensitivity towards physical and chemical conditions of the water, contribute useful information about the processes of eutrophication and pollution. In order to assess the biologica I river quality, two different indices have been proposed for monitoring rivers in Italy, one based on macroalgae and named EPI-M, the other based on diatoms and named EPI-D. The former is more rapid, the latter is without doubt more accurate; then the choice depends upon aim of the research.

Global change is frequently considered a major conservation threat. The Earth's c1imate has already warmed by 0.5 °C over the past century and Global Climate Models (GCM) have suggested a generai pattern of global warming over the next century or two. Some features of this warrning include a maximum warming in high latitudes, a displacement ofthe subtropical belt, in each hemisphere, a greater temporal and spatial variability in both temperature and precipitation, with stronger and more frequent violent storms and a reduced predictability of weather patterns. Recent studies show that it is possible to detect the effects of a changing climate on ecological systems. Most of approaches are based on models but experimental also exists. In order to know the vulnerability of specie s, climatic and biological boundaries are criticai data. For instance, plants in the Mediterranean region are mainly limited by moisture, so it is expected that a increase in atmospheric CO2 has a high effect on biodiversity in those biomes. Respect to vegetation types if their main structural elements have wide tolerance limits, they may be in the least danger of breakup. Vulnerability may also be reduced by greater diversity in main structural elements of a community. Models have shown that Quercus ilex s.l. community seems to be one of the most vulnerable vegetation types under a warming scenario. However the lack of knowledge concerning boundaries, i.e. the upper temperature limits of s...

Conséquences écologiques possibles des changements c1imatiques sur la flore et la végétation du bassin méditerranéenLes écosystèmes du bassi n méditerranéen constituent de remarquables ensembles-modèles pour l'étude des changements globaux, car la région méditerranéenne est une zone de transition sur le pIan bioclimatique, et selon plusieurs études prospectives récentes les changements climatiques devraient avoir là des effets majeurs,. \I est cependant très difficile, voire artificiel, de séparer les effets écologiques engendrés par les changements c1imatiques et atmosphériques de ceux occasionnés par les modifications du mode d' usage des terres, très variables selon les régions péri-méditerranéennes suite aux pressions anthropiques. Néanmoins, divers signaux c1imatiques et biologiques montrent que ce réchauffement dimatique est déjà bien perceptible en région méditerranéenne. L' extension de végétaux indigènes thermophiles dans la partie septentrionale et d'espèces sahariennes au sud, conjointement à celle d'exotiques doit ainsi s'expliquer en partie par l'amélioration des conditions thermiques, et par l' augmentation des taux de CO2 et d'azote atmosphériques. Au niveau des populations végétales, des changements phénologiques pourront modifier les interactions insectes-plantes et de nouvelles relations de prédation surviendront. La réponse des communautés végétales face à ces modifications environnementales ne sera pas univoque, mais il est probable que l'emprise...

El Omayed ' ROSELT' Observatory adopted a thematic procedure of evaluating and monitoring changes in natural resources. Data from previous studies was reworked to fit into the concerned themes. The trends of temporal change in the different va riables were evaluated using polynomi al curve fi tting confirmed by statisti cal analyses. The extracted trends indicate a steady increase in air temperature, re lative humidity and annual rain fa ll, while wind speed is declining. The standardi zed seasonal rainfa ll results in an autumn trend that approximates annual trend with amplitude of five years, while that during winter season is dec lining and that of spring is inclining above the long-term average starting mid nineti es. Concurrently, sodium, sulfate and chloride contents increased rapidly late in the nineti es joined with increasing the very fine sand fraction that refl ects the acti ve erosion and deposition processes associating recent human interference in the area. The temporal changes in the soil properties define the inland ridges as having the most stable conditions. The long-tenn records report 122 perenni als and 104 annuals of pl ant species residing in the observatory. Except for the inland plateau, there is a process of recharging the species di versity late in the nineties a l'ter experiencing a former sizable decline. Aiso detected is a change in the life-form spectrum towards larger woody component. Moreover and at the closing of the decade, the per...

Le vingtième siècle restera marqué dans l'histoire botanique récente des pays d'Afrique du Nord par l'ampleur des phénomèmes de dégradation qu'ont connus les écosystèmes de ces pays. Aucun milieu n'a échappé à ce fl éau. Trois principaux facteurs ont fait aboutir la situation à l'état dramatique actuel: pression anthropozoogène démesurée par rapport à la productivité et à la capacité de résilience des écosystèmes, stress c1imatique très fort et mauvaise gestion humaine. De nos jours, mis à part quelques rares exceptions, la meme tendance évolutive persiste et risque meme de s'aggraver dans le futur sous l'effet du "Changement climatique global" prédit par beaucoup d'études et de spécialistes. Comme ailleurs dans le monde, le "Changement global" aura des conséquences très importantes sur la végétation au Sud de la Méditerranée. Le bilan général reste difficile à évaluer; il dépendra beaucoup du sens et de l'intensité des variations de la pression anthropozoogène elle meme fonction de l'évolution socioéconomique des pays concernés.

The authors examined the relationship between the amount of geneti c diversity and some biological and populational characteristics (ploidy level, ratio of allogamy vs. autogamy, population size, existence and distance of other populations of the same species). Some case studies served to demonstrate that genetic diversity cannot be re liably predi cted a-priori, because it depends on the interaction of several factors. The importance of historical factors in determining infraspecific diversity is stressed. The authors conclude that reliable (i.e. directly measured) estimates of genetic diversity, both within populations and within individuals, are necessary in order to determine if a plant species is in need of conservation, to de fine conservation strategies, and to select germplasm sources for in situ or ex situ conservation.

Astragalus peterfii lav., a narrow endemie species, currently occurs in on ly 2 close localities and has been classified as endangered and/or rare in different Romanian and European red lists of plants. The goal of this study has been the evaluation of differences in terms of resource allocation between two populations located in contrasting habitats (near-closed meadows, within the Suatu 1 Natural Reserve and open vegetation on eroded soils) and the influence of community structure on the distribution pattern of ramets. The Astragalus ramets from the eroded, open lands invest much resource in vegetative regeneration by sprouting, but are fonned of small shoots. On the contrary, the ramets developed in near-close grasslands tend to produce taller shoots, more flowers and a larger proportion of fertile shoots, whereas a trade-off is reached by minimizing the resource investment in vegetati ve reproduction (growth of new shoots). The spatial aggregation of ramets is probably a consequence of both vegetati ve spreading and short-range dispersal of seeds. The differences in scale of aggregation detected along a coenocline from Stipa-rich grasslands (Stipion lessingianae) to Carex humilis-dominated lawns (Festuca rupicalae-Caricetum humilis) are due to a dramatic decline in ramets density. This observed pattern along with the negative correlation between the cover values of A. peterfii and C. humilis support the hypothesis that the forrner species multiplica...

This paper presents a review ofrare and endangered plant species in Rila mountain. Some relict and rare phytocoenosis with rare species for Bulgaria as well as Balkan Peninsula are described. The most endangered factor for the biodiversity in Rila mountain are noticed.

The study of genetic diversity, based on allele frequency has allowed to select the Sicilian wild populations of Brassica deserving conservation priority. The measurement of allele richness and the prcsence of local alleles have been used in order to describe genetic variation patterns belonging to different hierarchicallevels. The allele structure at subspecies level contributes to the total genetic diversity, the absolute contribution of a single population decreases with the increase of the number of sampled populations. Planning conservation at section level is of great advantage as regards conservation at subspecies level and can form the basis for the realization of the core collection. In order to preserve 37 all eles found in the Sicilian populations studied, priority has been given to al B. rupestris subsp hispida (Borgetto) and of B. incana (Gonato) popùlations for their allele richness b) B. macrocarpa population for the presence of the rare and local all ele 5 at locus Lap-l. c) B. incana (Longi) e B. villosa subsp bivoniana (Caltabellotta) for the presence of common and widely distributed alleles not captured in the populations already described in a and b. The survi val percentage ofthe seedlings of B. macrocarpa in nature is very low, this fact doesn 't allow the fruiting planls to produce a population able to maintain and preserve genetic diversity, for this reason ex situ conservation and reintroduction in the native habitat is...

The conservation biology is a multidisciplinary science that has developed in response to environmental changes that occurred during the last century and the need to propose effective measures ofconservation with a scientific background. It has conservation goals on the level ofpopulation, species, community and ecosystem. One of the most complex environmental problem is that ofthe plant community conservation. In order not to interrupt the evolutive processes, it is indispensable for each plant community type to maintain fragments that are in size and number sufficiently representative and that are able of self-organisation, self-regulation and selfregeneration. Unlike species, plant communities can only be conserved in situ (in their natural environment) and their preservation depends almost exclusively on the possibility of direct or indirect control by mano