Ecological features affect patterns of plant communities in Mediterranean temporary rock pools

In this paper, the results of a study on the ecology, floristic composition and spatial assemblages of temporary limestone rock pool plant communities of a central Mediterranean area (S Sicily, the Maltese Islands and Lampedusa) are presented. A total of 76 temporary pools were studied, distributed between the infra-mediterranean and thermo-mediterranean bioclimatic belt. For each temporary rock pools, the floristic composition and cover of the species were determined using standard relevé methods. Moreover, for 50 of these pools, pH, conductivity, soil depth, water-level, altitude and floristic richness and diversity index were assessed. The plant communities were analysed using unweighted pair group method using arithmetic averages and Euclidean distance classification and ordination methods such as canonical correspondence analysis (CCA). A total of four plant communities with specific floristic composition were established, each one with a different dominant species: Callitriche truncata; Elatine gussonei; Tillaea vaillantii and Lythrum hyssopifolia. According to the CCA, the spatial patterns of plant communities follow an ecological gradient related to water level and depth/size of the rock pools: these are the main ecological features affecting the distribution of the plant communities of rock pools. In addition, floristic richness and diversity index showed a slight increase in trend from temporary pools submerged for long periods towards pools submerged for short periods.     

The effects of some soil properties (soil nitrogen forms and moisture) on community structure in Mediterranean plant communities in the Black Sea region

Mediterranean ecosystems comprise the second biodiversity hotspot area after tropical rain forests and will be most affected by global climate change. Therefore, it is important to understand community dynamics for effective conservation in this region. We investigated the relationships between soil moisture, nitrogen forms and community structuring in Quercus ilexL., Erica arborea L. and Sarcopoterium spinosum (L.) Spach communities, representing different successional stages, distributed as Mediterranean enclaves on the Sinop Peninsula (Turkey). The soil moisture, ammonium, nitrate and nitrite content were measured seasonally. Differences in these abiotic parameters within and between communities over seasons were tested. Previously collected biotic data were then used to analyze the relationship between soil parameters and community structure. Significant differences in soil parameters within and between seasons were found within and between communities. Our results show that there are different relationships between soil moisture, nitrogen forms and community structure in Mediterranean plant communities representing different successional stages. Differentiation in vegetation structure during succession cause changes especially in the water and nitrate content of the soil, and these changes in turn affect the continuity of community structure in Mediterranean plant communities.     

Impact of grazing on the species richness of plant communities in Mediterranean temporary pools (western Morocco)

The impact of grazing on the vegetation of Moroccan temporary pools has been studied at 2 scales: regional (inter-pools) and local (intra-pools). Half of the 16 forest pools studied is located in a reserve and ungrazed. The other half, located within public forest, is grazed. Vegetation relevés coupled to water-depths measurements were carried out in each pool. The results showed a significant effect of grazing on both scales of analysis. This effect was found in the species composition of the vegetation, which differed between the 2 types of pools, and in the lower species richness and abundance of plant species in the grazed pools. These differences are interpreted as resulting from the selection by herbivores and the differential tolerance of species to disturbance. These impacts are likely to expose certain species to local extinction by reducing their populations.     

Size-fractionated phytoplankton chlorophyll in an Eastern Mediterranean coastal system (Maliakos Gulf, Greece)

The dynamics of phytoplankton biomass were studied in an Eastern Mediterranean semi-enclosed coastal system (Maliakos Gulf, Aegean Sea), over 1 year. In particular, chlorophyll a (chl a) was fractionated into four size classes: picoplankton (0.2–2 μm), nanoplankton (2–20 μm), microplankton (20–180 μm) and net phytoplankton (>180 μm). The spatial and temporal variation in dissolved inorganic nutrients and particulate organic carbon (POC) were also investigated. The water column was well mixed throughout the year, resulting in no differences between depths for all the measured parameters. Total chl a was highest in the inner part of the gulf and peaked in winter (2.65 μg l^–1). During the phytoplankton bloom, microplankton and net phytoplankton together dominated the autotrophic biomass (67.2–95.0% of total chl a), while in the warmer months the contribution of pico- and nanoplankton was the most significant (77.5–93.4% of total chl a). The small fractions, although showing low chl a concentrations, were important contributors to the POC pool, especially in the outer gulf. No statistically significant correlations were found between any chl a size fraction and inorganic nutrients. For most of the year, phytoplankton was not limited by inorganic nitrogen concentrations. Electronic Publication     

The role of competition by dominants and temperature in the foraging of subordinate species in Mediterranean ant communities

In this paper we test the influence of temperature and interference competition by dominant species on the foraging of subordinate species in Mediterranean ant communities. We have analyzed the changes in resource use by subordinate species in plots with different abundances of dominant ants, and in different periods of the day and the year, i.e., at different temperatures. The expected effects of competition by dominant species on foraging of subordinates were only detected for two species in the number of baits occupied per day, and for one species in the number of foragers at pitfall traps. In all three cases, subordinate species were less represented at baits or in traps in plots with a high density of dominants than in plots with a medium or low density of dominants. The number of workers per bait, and the foraging efficiency of subordinate species did not differ in plots differing in dominant abundance. Daily activity rhythms and curves of temperature versus foraging activity of subordinate species were also similar in plots with different abundance of dominant species, indicating no effect of dominants on the foraging times of subordinates. Instead, temperature had a considerable effect on the foraging of subordinate species. A significant relationship was found between maximum daily temperature and several variables related to foraging (the number of foragers at pitfall traps, the number of baits occupied per day, and the number of workers per bait) of a number subordinate species, both in summer and autumn. These results suggest that the foraging of subordinate ant species in open Mediterranean habitats is influenced more by temperature than by competition of dominants, although an effect of dominants on subordinates has been shown in a few cases. In ant communities living in these severe and variable environments, thermal tolerance reduces the importance of competition, and the mutual exclusion usually found between dominant and subordinate species appears to be the result of physiological specialization to different temperature ranges. Received: 8 May 1998 / Accepted: 30 July 1998     

Profile of cancer in the Eastern Mediterranean region: The need for action

BackgroundMany countries in the Eastern Mediterranean region (EMR) are undergoing marked demographic and socioeconomic transitions that are increasing the cancer burden in region. We sought to examine the national cancer incidence and mortality profiles as a support to regional cancer control planning in the EMR.MethodsGLOBOCAN 2012 data were used to estimate cancer incidence and mortality by country, cancer type, sex and age in 22 EMR countries. We calculated age-standardized incidence and mortality rates (per 100,000) using direct method of standardization.ResultsThe cancer incidence and mortality rates vary considerably between countries in the EMR. Incidence rates were highest in Lebanon (204 and 193 per 100,000 in males and females, respectively). Mortality rates were highest in Lebanon (119) and Egypt (121) among males and in Somalia (117) among females. The profile of common cancers differs substantially by sex. For females, breast cancer is the most common cancer in all 22 countries, followed by cervical cancer, which ranks high only in the lower-income countries in the region. For males, lung, prostate, and colorectal cancer in combination represent almost 30% of the cancer burden in countries that have attained very high levels of human development.ConclusionsThe most common cancers are largely amenable to preventive strategies by primary and/or secondary prevention, hence a need for effective interventions tackling lifestyle risk factors and infections. The high mortality observed from breast and cervical cancer highlights the need to break the stigmas and improve awareness surrounding these cancers.     

塔里木河流域荒漠河岸林群落的多元分析与环境解释

应用无偏对应分析（DCA）及二歧指示种分析（TWINSPAN）对塔里木河流域荒漠河岸林33个植物群落方资料进行了多元分析－排序和数量分类,并应用植物群落的排序值与环境参数的多元回归分析给出各群落类型的定量环境解释,探讨了该区植物群落的基本类型,生态梯度及其与环境因子的定量关系,结果表明,塔里木河流域漠河岸林的群落类型及其分布主要取决于土壤湿度和盐分含量,并可通过环境参数的数字表达式定量的确定。     

Messinian vegetation maps of the Mediterranean region using models and interpolated pollen data

This study proposes to compare the outputs from the CARAIB vegetation model forced by results from the LMD General Circulation Model with interpolated pollen data (Kriging method) from the Mediterranean region during the Messinian. The vegetation maps that have been obtained represent distinct phases of the salinity crisis: before the crisis and during the marginal evaporitic phase (interpolated map), and during the complete desiccation phase (simulated map). However, they are comparable in terms of vegetation density and agree on a strong contrast between the Northern (forest vegetation) and Southern (open vegetation) Mediterranean regions. Main differences concern the type of forests in the northern Mediterranean region, which are explained by discrepancies between precipitation amount predicted by the model and that calculated by a transfer function using pollen records. The interpolation method has been successfully tested in France using interpolated current pollen records by comparison with the present-day potential vegetation map. The resulting Messinian map is useful to validate or improve model simulation which does not take into account the depth of the Mediterranean Basin when it dried up. The Southern Mediterranean landscapes were open, with a steppe-like vegetation to the West and a savannah-like vegetation to the East. Forests prevailed to the North, organized in a mosaic system mainly controlled by relief. Such a contrast provides some explanation of the large number of deep fluvial canyons cut on the Northern margin at opposed to the South during the Mediterranean desiccation.     

天津近岸海域夏季大型底栖生物群落结构变化特征

近年来,天津海岸带区域经济发展迅速,污染物排放量及污染海域面积持续增加,特别是2004年以来,天津港和临港工业区进行了大规模的海洋工程建设。由于具有迁移能力差、随季节波动不明显、生命周期相对较长等优点,大型底栖生物作为重要的人类干扰的反应指标,被广泛的应用于河口和海岸带生态系统对人类干扰的环境响应评价。为研究遭受人类干扰活动的天津近岸海域大型底栖生物群落结构的时空变化特征,分别于2004年和2007年夏季对渤海湾天津近岸海域进行了大面积的底栖生物群落调查。运用聚类分析、多维标度(MDS)及相似性分析(ANOSIM)等多元统计方法,分析了该区域底栖生物丰度、优势种、群落结构及生物多样性的时空变化特征。结果表明:1)2004年夏季底栖生物调查获得底栖生物29种,平均丰度为402.8个/m²,优势种为日本鼓虾、脆壳理蛤;2007年夏季底栖生物调查获得底栖生物36种,平均丰度为120.27个/m²,优势种为脆壳理蛤、小胡桃蛤、绒毛细足蟹、涡虫4种。2)2004年,调查区域底栖生物丰度空间分布呈现北低南高特征,2007年,则呈现中间低南北高的空间分布特征。3)2004年到2007年,位于大沽河口的19号站点底栖生物群落结构与其它站点存在显著性差异,生物群落受冲淡水影响明显,具有河口生物群落结构的独特性。2004年调查区域中的塘沽断面的底栖生物群落结构与其它四个断面存在显著性差异,而到2007年,五个断面底栖生物群落结构整体趋向一致。4)2004年,北部北塘、汉沽及南部岐口断面具有较高的丰富度、均匀度、多样性及较低的优势度指数,而到2007年,南部岐口、北部汉沽区域丰富度、均匀度和多样性指数均呈现下降趋势,而优势度指数则有所上升。中部区域特别是塘沽断面在丰富度、均匀度、多样性指数上有所增加,且越靠近中心区域增加程度越大。海岸工程、污染物排放、围垦养殖等人为干扰因素可能是造成天津近岸海域底栖生物丰度降低及其群落结构和多样性指数空间分布不均匀变化的主要原因。     

Relationship between freshwater gastropods and plant communities reflecting various trophic levels

Plant communities were examined in ponds in Brittany (north-west France) and then classified into six types reflecting different trophic levels: oligotrophic, oligodystrophic, mesotrophic, meso-dystrophic, meso-eutrophic an eutrophic. In 45 of these ponds, aquatic snails were sampled in order to determine the relationship between the gastropod species richness and the water trophic levels as indicated by plant community types. The second aim of this study was to determine whether some gastropod species were characteristic of a particular trophic level. The number of plant communities in the ponds was also taken into consideration.A trophic gradient was found along the F1 axis on the principal plane of the correspondence analyses. The species richnesses low or zero and especially the lymneid, Lymnaea glabra were close to the oligo-dystrophic and oligotrophic communities. In contrast, the highest numbers of snail species (5 and above) were found in the most eutrophic ponds where Hippeutis complanatus, Planorbis planorbis, Lymnaea stagnalis and Planorbarius corneus were particularly common. The latter species inhabited the ponds including on average the greatest number of macrophyte communities but no significant differences were found between snail species. The ponds which contained the greatest numbers of plant communities included the richest gastropod communities (7 and more) but also the poorest ones (0 or 1 species). Relationships between freshwater snails, macrophytes and trophic levels are discussed.Laboratoire de Zoologie et d'Ecophysiologie     

Phenological and biogeographical aspects of coastal dune plant communities in southern Brazil

The coastline of southern Brazil is characterized by vast sand dunes. From March 1982 to April 1984 the dune vegetation was sampled along a transect between the Atlantic shore and an inland freshwater marsh, and phenological cycles of plant species were observed at monthly intervals.The occurrence of 23 annual species in the local dunes and peak germination, growth and flowering of 21 perennial species during spring, summer and fall, suggest that unfavourable temperatures and inundation of slacks during winter are seasonally limiting factors for this flora.Differences in the floristic composition between this region and its southern and northern extremes in the southwestern Atlantic together with a marked seasonality of the total species number and of germination and flowering periods, suggest that this area corresponds to a warm temperate biogeographic transition zone between northern tropical and southern cold temperate regions.     

Changing assembly processes during a primary succession of plant communities on Mediterranean roadcuts

Aims Studying plant ecological succession provides insights into the spatiotemporal processes underlying community assembly and is of primary importance for restoration ecology. We investigate here colonization events and local community assembly over an original primary succession occurring on roadcuts after roadwork. For this, we addressed both the changes in species presence-absence (incidence data) to highlight pre-establishment filters and in species relative abundances to further assess the influence of local biotic processes.Methods We studied 43 limestone roadcuts in Mediterranean France, covering five age classes up to an age of 80 years, along with 13 natural cliffs as a reference, and we counted 14322 plant individuals on these sites. We applied a constrained nonsymmetric correspondence analysis of both the incidence (presence-absence) and abundance data to assess the variation of these data along the chronosequence.Important findings Along the first 30 years, the initially abundant short-lived species declined both in terms of incidence and abundance and were replaced by longer lived herbaceous and woody species. This first phase was characterized by species that are widespread in the surrounding scrublands and was comparable to an early secondary succession there. After 30 years, there were continuing changes in incidence data with age, but no more significant change in species' abundances. This second phase was marked by the late colonization of specialists that did not become dominant. Although colonization and establishment limitation was thereby apparent for specialist species, a slow convergence of community composition toward the situation of natural cliffs could be detected in the older stages of the chronosequence. These findings convey insights into the natural dynamics of man-made outcrop plant communities and may be useful for the ecological management and restoration of such contexts. It also illustrates the interest of comparing incidence and abundance data to investigate the relative influence of ecological determinants on the assembly of plant communities.     

Biogeographical network analysis of plant species distribution in the Mediterranean region

The delimitation of bioregions helps to understand historical and ecological drivers of species distribution. In this work, we performed a network analysis of the spatial distribution patterns of plants in south of France (Languedoc‐Roussillon and Provence‐Alpes‐Côte d'Azur) to analyze the biogeographical structure of the French Mediterranean flora at different scales. We used a network approach to identify and characterize biogeographical regions, based on a large database containing 2.5 million of geolocalized plant records corresponding to more than 3,500 plant species. This methodology is performed following five steps, from the biogeographical bipartite network construction to the identification of biogeographical regions under the form of spatial network communities, the analysis of their interactions, and the identification of clusters of plant species based on the species contribution to the biogeographical regions. First, we identified two sub‐networks that distinguish Mediterranean and temperate biota. Then, we separated eight statistically significant bioregions that present a complex spatial structure. Some of them are spatially well delimited and match with particular geological entities. On the other hand, fuzzy transitions arise between adjacent bioregions that share a common geological setting, but are spread along a climatic gradient. The proposed network approach illustrates the biogeographical structure of the flora in southern France and provides precise insights into the relationships between bioregions. This approach sheds light on ecological drivers shaping the distribution of Mediterranean biota: The interplay between a climatic gradient and geological substrate shapes biodiversity patterns. Finally, this work exemplifies why fragmented distributions are common in the Mediterranean region, isolating groups of species that share a similar eco‐evolutionary history.     

Environmental science and management of coastal lagoons in the Southern Mediterranean Region: key issues revealed by the MELMARINA Project

Lagoons in the heavily populated, semi-arid coastal zone of the Southern Mediterranean Region exemplify the conflict between human utilisation of water and related resources and aquatic ecosystems. Having recognised the requirement to improve understanding of the functioning of the region’s coastal wetlands, the MELMARINA Project undertook integrated hydro-ecological monitoring and modelling within lagoons in Morocco, Tunisia and Egypt. This article highlights some key issues regarding environmental science and management of the region’s coastal lagoons revealed during the course of the project. It stresses the importance of hydrology as a key control upon lagoon functioning and ecosystem dynamics. Hydrological modifications due to water resource management schemes are the cause of many recent changes experienced within lagoons. Linkages between water quality, water availability, human activities and biological characteristics of coastal lagoons are discussed with particular reference to the controls upon vegetation within the MELMARINA lagoons. A series of methodological advances are reviewed which have potential for wider application within coastal lagoons. It is suggested that the use of lagoon sediment for environmental reconstruction can be invaluable, especially when monitoring data are lacking. Recent advances in instrumentation technologies make long-term continuous monitoring more feasible although these approaches can be combined with more traditional site surveys to provide wider spatial coverage at the expense of temporal resolution. Wider spatial coverage can also be achieved through the use of space-borne or aerial remote sensing imagery whilst longer-term trends in site characteristics can be assessed through historical map analyses. Geographical Information Systems, which facilitate the storage and interrogation of large and varied datasets, have enormous potential. Similarly, coupled hydro-ecological models can inform understanding of lagoon functioning and can assess scenarios associated with environmental change or alternative management approaches. The application of integrated, basin-wide approaches to the management of water resources and aquatic ecosystems in the Southern Mediterranean Region is advocated. This includes the application of principles from the EU’s Water Framework Directive. Finally, the need to place management in the context of climate change and associated sea level rise is stressed. Emphasis should be placed on the development of adaptation strategies designed to minimise the effects of these changes. Guest editors: J. R. Thompson & R. J. Flower Hydro-ecological Monitoring and Modelling of North African Coastal Lagoons     

Refinements of calcareous nannofossil biostratigraphy at the Miocene/Pliocene Boundary in the Mediterranean region

The high-resolution quantitative study of the calcareous nannofossil assemblages in two Mediterranean deep-sea successions (ODP Sites 969B and 975B) encompassing the Miocene/Pliocene boundary allows the recognition of a set of reliable bioevents useful to detecting the base of the Zanclean stage. The results have been successfully compared with two on-land sections (Cava Serredi, Tuscany, and Montepetra borehole, Marche Region, Central Italy). This study confirms that Ceratolithus acutus and Triquetrorhabdulus rugosus, the markers traditionally used for identifying the Miocene/Pliocene Boundary are very rare in the Mediterranean area and cannot be used for biostratigraphic correlation. Conversely, the absence interval (paracme) of Reticulofenestra pseudoumbilicus and the distribution range of a new species belonging to the Reticulofenestra genus (Reticulofenestra zancleana nov. sp.) show high biostratigraphical potential. The position of the new biohorizons has been compared to those of the planktonic foraminifers events, and correlated to the CaCO₃ cycles reconstructed for the two sections. On the basis of these new nannofossil bioevents, Rio et al.’s (1990) MNN12 biozone is subdivided into three subzones, thus improving the biostratigraphic resolution of the Early Pliocene.     

Biogeographic and demographic changes in the distribution and abundance of scorpions inhabiting the Mediterranean region in northern Israel

A recent survey of the scorpion fauna in the Mediterranean region of northern Israel, has shown that the desert buthid, Leiurus quinquestriatus, formerly restricted to the arid and semi-arid regions in southern and eastern Israel, has penetrated through the Jordan Valley deep into the Mediterranean region, reaching into the northern Galil Mountains. At the same time, the oakwood scorpionid, Scorpio maurius fuscus, formerly the most abundant scorpion in the Mediterranean region, showed a marked decline in numbers. Various aspects of this apparent colonization and replacement in the scorpion fauna are discussed.     

The chironomid fauna of the Mediterranean region reviewed

From the Mediterranean countries, Italy, France (southern), Spain, Portugal, Morocco, Algeria, Tunisia, Lebanon, Syria, Turkey, Greece and Yugoslavia and according to published and as yet unpublished data, about 703 Chironomid species are known. 97 of the species are exclusive to the Mediterranean region. For three speciesCricotopus beckeri, Eukiefferiella bedmari andParatanytarsus mediterraneus a pointdistribution map is given.29 species listed with an Afrotropical distribution also reach into various parts of the Mediterranean area. As an example, a point-distribution map ofParatrichocladius micans is given. Seven species with a Panpalaeotropical distribution are known in the Mediterranean region. The great majority of the other 570 species (81%) most likely have a Palaearctic distribution. However, accurate distribution data of many species are as yet not available. This holds in particular for species with an assumed Southpalaearctic distribution. For chironomids of the Mediterranean fauna a differentiation into Circum- and West-Mediterranean subgroups is not yet possible. The Afrotropical species reach the Mediterranean region chiefly by the Nile valley. Nevertheless, some apparently relict Afrotropic species in the South of Morocco may suggest a West-African progression towards the Mediterranean. The Syrian-East African rift valley may also be considered as a migration path for West Palaearctic and especially Oriental chironomids into the Afrotropic region.     

Structure of ground-foraging ant assemblages in relation to land-use change in the northwestern Mediterranean region

The abandonment by humans of marginal and less productive zones signifies an important change in land use in North Mediterranean agroecosystems. Human perturbations have led to a highly diversified landscape, with a mosaic made up of patches of land at different stages of succession, from cultivated fields to closed forest. Our aim here is to characterize ant assemblages and their functional groups in response to these land-use changes. This progressive abandonment results in an initial increase in ant richness and abundance, which can reach high levels if the succession proceeds as far as woodland. In terms of the ant functional groups, this land-use change implies: (1) the appearance of Subordinate Camponotini; (2) an increase in Generalized Myrmicinae, Cryptics and Cold-climate specialists in terms of ant species richness, overall abundance and, for Generalized Myrmicinae and Cryptics, an increase in abundance percentage; (3) a decrease in percentage abundance of Opportunists; (4) a progressive decrease in species richness as well as overall and percentage abundance of Hot-climate Specialists throughout the transformation from crops to woodlands; and (5) an initial increase of Dominant Dolichoderinae followed by a decrease in ant species richness, overall abundance and percentage abundance. Using the ant functional group approach for the clearly separate stages of the regeneration process is a promising method for comparing responses of ant communities to human land use.