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1.
The aim of this research was to evaluate plant diversity and the relationships between the distribution of Raunkiaer life forms and community structure, and species richness, at different successional stages in communities of Quercus ilex L., Erica arborea L. and Sarcopoterium spinosum (L.) Spach., distributed as enclaves in Sinop Province. Permanent sample plots were selected to determine plant diversity. The cover percentage of each plant species was recorded monthly during two vegetation periods. Raunkiaer life forms, and the Shannon–Wiener, Evenness, Simpson and Margalef indexes were determined. Twenty-three species in Quercus ilex, 96 species in Erica arborea, and 148 species in Sarcopoterium spinosum were identified. Hemicryptophyte dominancy was observed followed by phanerophytes in the Q. ilex community, and therophyte and hemicryptophyte dominancy in the E. arborea and S. spinosum communities, respectively. It was determined that the S. spinosum community was the most heterogeneous community while the Q. ilex community was more uniform than other communities. The variation in diversity indexes, homogeneity, and composition of life forms among communities adopting a similar climatic environment could result from a differentiation of environmental factors, which impact on community structuring, from biotic to abiotic at different successional stages of Mediterranean communities.  相似文献   

2.
Parietaria judaica (Urticaceae) grows abundantly in urban areas of the Mediterranean region. Its pollen is a major allergy source. We studied the species’ distribution and abundance in and around Thessaloniki (Greece), pollen production and pollen season. We also examined how urban pollution affects pollen viability. Our ultimate goal was to obtain an estimate of the species’ performance and ability to expand under different environmental conditions related to climate change. We mapped P. judaica and the other Urticaceae species. In a north- and a south-facing population, we recorded the progress of P. judaica flowering and estimated the pollen content per flower, shoot and surface unit. We concurrently assessed atmospheric circulation of Urticaceae pollen. We estimated P. judaica pollen viability and Cu, Pb and Zn concentrations in plants collected from sites differing in traffic intensity. P. judaica is the most abundant Urticaceae species in the area; its occurrence has increased dramatically over the last 100 years. Production of flowers is intense in spring and autumn. Flowering started 12 days earlier in the south-facing population in spring, and 3 days later in autumn. Pollen production was higher in spring and in the south-facing population. Flower and pollen production were positively correlated with the size of the plant and the flower, respectively. Copper and lead concentrations in plants were positively correlated with pollen viability, which was higher for plants collected from high-traffic sites. P. judaica has a high phenotypic plasticity; this is a feature that promotes success of expansive and invasive species. It is also well adapted to warm and polluted urban environments. The climatic change forecast for the Mediterranean region could provoke earlier, longer, and more pronounced flowering and, consequently, more P. judaica pollen in the air. In return, this would result in increased severity of Parietaria pollinosis.  相似文献   

3.
Particulate matter (PM) as an air pollutant can be harmful for human health through allergic, mutagenic and carcinogenic effects. Although the main focus is on decreasing air pollution, after PM has been emitted to the atmosphere, one of the realistic options to decrease it's concentrations in urbanized area will be phytoremediation. This study compared the capacity to capture PM from air of seven tree species commonly cultivated in Poland (Catalpa bignonioides Walter, Corylus colurna L., Fraxinus pennsylvanica Marsh., Ginkgo biloba L., Platanus × hispanica Mill. ex Muenchh., Quercus rubra L., Tilia tomentosa Moench ‘Brabant’) and six shrub species (Acer tataricum subsp. ginnala (Maxim.) Wesm., Sambucus nigra L., Sorbaria sorbifolia (L.) A.Br., Spiraea japonica L.f., Syringa meyeri C.K. Schneid. ‘Palibin’, Viburnum lantana L.). Significant differences were found between species in mass of total PM accumulation for two PM categories and three size fractions determined and in amount of waxes. A positive correlation was found between in-wax PM of diameter 2.5–10 μm and amount of waxes, but not between amount of waxes and amount of total PM or of any size fraction.  相似文献   

4.
M. Boi  L. Llorens 《Aerobiologia》2013,29(3):385-397
This aeropalynological study documented the pollen of 13 taxa with the highest concentration in the air of Palma de Mallorca during the years 2004–2010, using a Hirst-type volumetric spore trap. The taxa were Cupressaceae, Olea europaea, Platanus hispanica, Pinus spp., Parietaria judaica, Urtica membranacea, Quercus ilex, Poaceae, Chenopodiaceae/Amaranthaceae, Plantago spp., Castanea sativa, Pistacia lentiscus and Betula spp. These taxa accounted for 91.85 % of the total annual pollen recorded during the period. The mean annual pollen index was 20,027. The highest pollen counts occurred in February–June, representing 88.74 % of the annual total collected. Every year, there was a substantial increase in the concentration and types of pollen from March to May, followed by a decrease from July to January. The maximum annual total pollen count was recorded in 2005 with 25,870 and the minimum in 2009 with 14,726. The mean daily average pollen concentration count showed a declining trend over the study period. With respect to seasonal phases analysed, the later phase of the pollen season is more variable than the beginning. To observe the overall dynamics of the different pollen types better, a pollen calendar was established for Palma de Mallorca. The pollen calendar had typical Mediterranean features and is a useful tool for allergological and botanical awareness.  相似文献   

5.
A pollen analytical study of a 66-m long core from the Brague valley, Biot, Alpes-Maritimes, France, suggests that thalwegs in eastern Provence may have served as refugia for mesophilous trees such asTilia, Fagus andAbies during the last glacial period. During the Younger Dryas the vegetation was considerably less steppic in character than that described from western Provence. The varying role of taxa such asQuercus ilex-type in pollen profiles from the wider region suggests a longitudinal gradient in both climate and vegetation development in the French/Italian north-western meditcrranean region during the Holocene.  相似文献   

6.
ABSTRACT

Six species of the Quercus genus (Quercus ilex L., Q. coccifera L., Q. suber L., Q. trojana Webb, Q. macrolepis Kotschy, Q. cerris L.) have been screened for cytosolic ascorbate peroxidase (APX) by means of native polyacrylamide gel electrophoresis (PAGE). A single isozyme was found in five species (Q. trojana, Q. suber, Q. cerris, Q. macrolepis and Q. coccifera), while Q. ilex shows two different APX proteins. The data showed marked similarities among Q. trojana, Q. suber, Q. cerris and Q. macrolepis with respect to the electrophoretic mobility. The validity of APX electrophoretic patterns in systematic studies is discussed.  相似文献   

7.
Micronutrient concentrations in foliage and stemwood (including bark) of six European tree species (Betula pendula Roth., Quercus robur L., Fraxinus excelsior L., Fagus sylvatica L., Tilia cordata Mill. and Picea abies (L.) Karst.) planted on the same type of soil at six sites in three different countries were studied. Micronutrient concentrations in foliage were considerably higher than in stemwood for all elements and species studied, except for Fe in spruce. Interspecies comparisons revealed significant differences in concentrations both in foliar and stemwood biomass, as well as in stemwood:foliage nutrient ratios. Lime foliage showed a considerably higher concentration of B than all other species, while the stemwood concentration of this element was highest in ash. Mn concentration in both foliar and stemwood biomass of ash was extremely low compared with concentrations in other species. Birch stemwood showed nearly double the level of Zn in other species at all sites. Zn concentrations in the birch foliage were also higher than in other species, with the exception of the Lithuanian sites, which showed lower EDTA-extractable Zn concentrations in the soils. The concentration of Cu was lowest in spruce foliage, while Cu concentrations in stemwood were similar in all species. It was concluded that species-related differences in microelement nutrition must be taken into account when evaluating the nutrient status of common European forest tree species, and when using them as bio-indicators of the effects of environmental pollution.  相似文献   

8.
The vegetative resprouting of mediterranean maquis shrubby species was examined eight years after fire. Post-fire regeneration occurs through the resprouting of stumps. All species (Quercus ilex L., Phillyrea latifolia L., Arbutus unedo L., Erica arborea L., Pistacia lentiscus L.) show a rapid growth in the first years after fire, and a decrease already from 4th–5th year.All the species survived the fire and reconstituted a community similar to that unburned in a relatively short time span.  相似文献   

9.
This study examined the photosynthetic and growth performances of potted plants of Cistus albidus L. and Quercus ilex L. submitted either to natural Mediterranean winter conditions or to mild greenhouse conditions. Plants grown outdoors exhibited lower light and CO2-saturated CO2 assimilation rates (Asat) and apparent quantum yield (i) than those indoors. Until mid-winter, C. albidus had higher Asat than Q. ilex, but differences disappeared after a period of severe cold. Maximal photochemical efficiency of PSII (Fv/Fm) measured predawn was higher in C. albidus than in Q. ilex, and decreased throughout the season in outdoor plants. Fv/Fm also decreased at light saturation (Asat) in both species. Fv/Fm was correlated with photosynthetic capacity and efficiency (quantum yield), but the resulting regression slopes were different between the two species. At the physiological level, C. albidus seemed to cope better with cold stress than Q. ilex. However, winter stress induced reduction of leaf absorptance, increased leaf mass per area, extensive leaf damage and high plant mortality in C. albidus. This suggests that the high performance of C. albidus leaves is not likely to be maintained for long periods of cold stress, and may therefore depend on continuous leaf replacement. Quercus ilex showed a conservative behaviour, with low net assimilation rates but greater leaf and plant survival than C. albidus.  相似文献   

10.
Despite the huge biodiversity characterizing the Mediterranean environment, environmental constraints, such as high sunlight and high temperatures alongside with dry periods, make plant survival hard. In addition, high irradiance leads to increasing ozone (O3) concentrations in ambient air. In this era of global warming, it is necessary to understand the mechanisms that allow native species to tolerate these environmental constraints and how such mechanisms interact. Three Mediterranean oak species (Quercus ilex, Quercus pubescens and Quercus cerris) with different features (drought tolerant, evergreen or deciduous species) were selected to assess their biometrical, physiological and biochemical responses under drought and/or O3 stress (80–100 nl l?1 of O3 for 5 h day?1 for 77 consecutive days). Leaf visible injury appeared only under drought stress (alone or combined with O3) in all three species. Drought × O3 induced strong reductions in leaf dry weight in Q. pubescens and Q. cerris (?70 and ?75%, respectively). Alterations in physiological (i.e. decrease in maximum carboxylation rate) and biochemical parameters (i.e. increase in proline content and build‐up of malondialdehyde by‐products) occurred in all the three species, although drought represented the major determinant. Quercus ilex and Q. pubescens, which co‐occur in dry environments, were more tolerant to drought and drought × O3. Quercus ilex was the species in which oxidative stress occurred only when drought was applied with O3. High plasticity at a biochemical level (i.e. proline content) and evergreen habitus are likely on the basis of the higher tolerance of Q. ilex.  相似文献   

11.
The diverse pollutants emitted from automobiles can have adverse effects on the health and survival of plants, animals and human beings. Different plant species have been known to possess high potential of absorption, detoxification and tolerance of high levels of pollution. Considering this, the present study was carried out to assess the impact of automobile pollution on palynology of roadside plants. Three species, viz. Cannabis sativa, Cassia fistula and Thevetia peruviana growing along the roadsides of nine sites of Amritsar city under different levels of traffic stress were selected for the study. Pollen viability and pollen size were studied by staining pollen with 2,3,5-triphenyl tetrazolium chloride stain and observed under light microscope. Scanning electron microscope was used to study the changes in morphology of the pollen grains. It was observed that the percentage of pollen viability of three species was inversely proportional to the load of traffic at a particular site. Pollen viability was observed to be minimum (C. sativa—22.58 %; C. fistula—21.30 %; and T. peruviana—6.22 %) for the plants of the three species studied growing at traffic site I, site with heavy traffic load as compared to plants growing at sites with comparatively lesser traffic load. C. sativa growing at traffic site IV showed maximum pollen viability of 79.74 %, while C. fistula and T. peruviana growing at traffic site VIII exhibited maximum pollen viability of 83.32 and 68.78 %, respectively. Pollen size and morphology did not show any significant variation and remained unaffected with the increase in traffic stress.  相似文献   

12.
Abstract. Germination of Quercus ilex L. in coppice stands of this species in the western Mediterranean Basin was examined and a germination inhibitory process is proposed to explain some germination traits. Germination rate and seedling biomass of Q. ilex were greatly modified by watering acorns with various concentrations of aqueous soil extracts from a Q. ilex coppice stand but also when the acorns were sown in soil from Q. ilex coppice stands. In the aqueous extract experiment, Q. ilex germination and seedling weight both decreased as the aqueous extract concentration increased. In the soil type experiment, Q. ilex soil decreased the Q. ilex germination rate. Comparative studies with Q. pubescens germination (this species, replaced by Q. ilex around 5 000 B.P., is assumed to form the climax vegetation of the region) revealed that Q. pubescens was less sensitive to the aqueous extracts and soils of Q. ilex coppice stands. Inhibition of Q. ilex seed germination could be a major reason for the poor seed regeneration and suggested a possible comeback of Q. pubescens.  相似文献   

13.
European oaks have been reported to emit isoprene or monoterpenes derived from recently fixed photosynthetic carbon. The emission type is plant species specific and can be used as chemo‐taxonomic marker. In the present article the isoprenoid biochemical properties of mature Quercus × turneri‘Pseudoturneri’ hybrids resulting from a crossing of a Mediterranean evergreen monoterpene‐emitting species (subgenus Sclerophyllodrys; Quercus ilex L.) and an isoprene‐emitting deciduous oak species (subgenus Lepidobalanus; Quercus robur L.) are described. Both species are compared with respect to the capacity for isoprenoid synthesis and the actual isoprenoid emission pattern of different tree‐types. The analysis showed that the oak hybrid combines properties of both parental species. Furthermore, it could be shown that the enzyme activities of isoprene synthase and monoterpene synthases are reflected in the isoprenoid emission pattern of the hybrids as well as in the observed emission rates.  相似文献   

14.
Abstract

The xylem conduit dimensions (i.e. their width and length) have been measured in 1-year-old internodes, nodes and node-to-petiole (N-P) junctions of three species with diffuse-porous wood, namely Ceratonia siliqua L., Laurus nobilis L. and Olea europaea L. as well as of three species with ring-porous wood, namely Quercus ilex L., Q. suber L. and Q. pubescens Willd‥ The xylem conduit diameter and length distributions have been related to the drought resistance strategies adopted by the six species. C. siliqua and Q. ilex (drought avoiding water spenders) showed the widest xylem conduits (each species within its characteristic pattern of wood anatomy). This is consistent with their high demand of efficient water transport to leaves. L. nobilis (drought avoiding water saver) showed relatively narrow xylem conduits, efficient enough, however, to assure water supply to leaves at the reduced transpiration rate exhibited by the species. O. europaea, Q. suber and Q. pubescens (drought tolerants) showed the narrowest xylem conduits but also the longest ones. The xylem system of C. siliqua and Q. ilex represented a good compromise between efficiency and safety of the water transport, the former as due to wide xylem conduits, the latter to the reduced xylem conduit length as well as to the strong «hydraulic constrictions» at their nodes and N-P junctions. The ecological interpretation of such hydraulic architecture is discussed.  相似文献   

15.
Concentrations of Ni were determined in xylem and phloem of Quercus ilex trees growing on serpentine and sandy loam soils of northeast Portugal. Radial distribution patterns of Ni in stemwood were compared to variations in annual growth increments of the trees.Concentrations of Ni in xylem and phloem were higher in Q. ilex from serpentine soil, when compared with Q. ilex of a sandy loam soil.The radial distributions of Ni showed large variations among the trees, although they all grew in the same area within a short distance from each other. These differences can be caused by small-scale spatial variations in the soil. Therefore, the use of such radial Ni distributions for a retrospective biomonitoring of the Ni pollution of larger areas appears questionable.  相似文献   

16.
Resprout and mature plant shoot growth, leaf water status and gas exchange behavior, tissue nutrient content, flowering, and production were studied for co-occurring shallow-rooted (Arbutus unedo L.) and deeprooted (Quercus ilex L.) Mediterranean tree species at the Collserola Natural Park in Northeast Spain Resprouts showed higher growth rates than mature plant shoots. During fall, no differences in eco-physiological performance of leaves were found, but mobilization of carbohydrates from burls strongly stimulated growth of fall resprouts compared to spring resprouts, despite low exposed leaf area of the fall shoots. During summer drought, resprouts exhibited improved water status and carbon fixation compared to mature plant shoots. Shoot growth of Q. ilex was apparently extended due to deep rooting so that initial slower growth during spring and early summer as compared to A. unedo was compensated. Tissue nutrient contents varied only slightly and are postulated to be of minor importance in controlling rate of shoot growth, perhaps due to the relatively fertile soil of the site. Fall flowering appeared to inhibit fall shoot growth in A. unedo, but did not occur in Q. ilex. The results demonstrate that comparative examinations utilizing vegetation elements with differing morphological and physiological adaptations can be used to analyze relatively complex phenomena related to resprouting behavior. The studies provide an important multi-dimensional background framework for further studies of resprouting in the European Mediterranean region.  相似文献   

17.
Barberis  G.  Peccenini  S.  Paola  G. 《Plant Ecology》1992,99(1):35-50
The climatic characteristics of the Liguria region have been outlined by means of raw data and derived indices (water balance related to potential evapotraspiration, Rivas-Martinez's index of mediterraneity and thermicity, De Martonne's index of dryness, and Emberger's pluviothermic quotient and index of summer dryness). Their interpretation suggests that Liguria is a boundary region between two different climatic areas: the Mediterranean and that of Central Europe.The distribution of Quercus ilex communities in Liguria have suffered the heavy consequences of human activity on the coastal belt of the region. There is, however, sufficient evidence to show that their presence is closely linked to climatic conditions. Quercus ilex communities are absent from the western coastal belt where the annual water balance is below –50 mm and high mean temperatures occur. They are also absent from marly limestone dominated areas where annual water balance is below 300 mm. Quercus ilex woods show a preference for water balance values between 0 and 600, with the better developed forests being found in central and eastern coastal Liguria.The Ligurian Quercus ilex woods are ascribed to Quercetum ilicis Br.-Bl. 1915. Given that the presence within their floristic composition of a group of species of Querco-Fagetea (more species in eastern stands, few in western ones) is an almost constant characteristic, the subass. fraxino-ostryetosum Mariotti 1984 can be retained for many of them. Quercus ilex is not present in the initial succession stages of Mediterranean Liguria vegetation. It can be found in later stages when the vegetation is more fully developed towards a maquis type structure. In this case it tends to become dominant and the community develops (if no fire or other human interference occurs) into a Quercus ilex forest. Frequently, this succession takes place under an old tree layer cover (generally Pinus sp.), a remanant of man's past management of the vegetation in the area.  相似文献   

18.
The palynological analysis of the Burdigalian (Early Miocene) successions of the Güvem Basin (NW Central Anatoia, Turkey) has been carried out with the aim of reconstructing the palaeovegetation. The pollen spectra indicate a flora dominated by trees such as Quercus deciduous type, Carya, Carpinus, Ulmus/Zelkova, Engelhardia, Quercus ilex type and Pinaceae. Pterocarya, Juglans, Alnus, Salix, Liquidambar and Oleaceae are represented by lower percentages. Herbs and shrubs are represented by minor amounts of Poaceae, Amaranthaceae/Chenopodiaceae, Asteraceae/Asteroideae, Brassicaceae, and the aquatics Potamogeton, Sparganium and Typha. The Burdigalian flora reflects a mixed mesophytic forest with Quercus deciduous type, Quercus ilex type, pine species, Ulmus/Zelkova, Engelhardia, Carya, Carpinus, Pterocarya, etc., sparcely interspersed with open herbaceous areas. This flora reflects a warm-temperate climate. The fluctuations in abundances of broadleaved trees and xerophytes may represent fluctuations of relatively wet and dry periods. The overall composition of the flora of the Güvem Basin reflects cooler conditions compared with other Early Miocene floras in Europe, which is possibly due to intense volcanic activity of the area.  相似文献   

19.
Biosolids have been widely used for land reclamation, but information on their use in restoration, i.e., on less degraded areas, is scarce. Biosolids may be used to restore forest ecosystems by fostering tree establishment in degraded shrublands. Detailed knowledge on the effects of biosolid application is needed to optimize such practice. We evaluated the effect of different rates (0, 7.5 and 14.5 kg dry weight per plant) and types of biosolid application on the performance of Pinus halepensis and Quercus ilex seedlings, and operational costs. Biosolids increased seedling mortality in both species, particularly when seedlings were planted in direct contact with them. Mortality mostly occurred during the first year, and was probably favored by soil shrinking and salinity. Foliar and needle nitrogen concentration increased with biosolid rate in the short term, but biosolids affected negatively (P. halepensis), or had no effect (Q. ilex) on phosphorus and potassium concentration. Biosolids had a positive effect on P. halepensis growth, and a negative effect on Q. ilex growth at the highest rate when seedlings were in contact with biosolids. Cost of this type of biosolid application approximately doubled plantation cost, but were similar or cheaper that landfill disposal of biosolids. The lowest application rate showed the best balance between seedling response and costs for P. halepensis, whereas biosolid use cannot be recommended for Q. ilex.  相似文献   

20.
Gratani  L.  Marzi  P.  Crescente  M. F. 《Plant Ecology》1992,(1):155-161
The annual course of vegetative growth of the most representative species of a Quercus ilex L. forest in Castelporziano (Latium, Italy) was studied through periodical analysis of selected ecophysiological leaf indexes, for the period 1987–1990. The results demonstrate that the local climate facilitates continuous vegetative activity of the sclerophyllous species without a latent phase. The variable morphology of sun and shade leaves of Q. ilex illustrates the plant's response to environmental stress.  相似文献   

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