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1.
The phytoremediation potential of the halophyte Limoniastrum monopetalum for the removal of Cd and Pb from polluted sites is assessed in this work. Two pot experiments were conducted; the first with wild L. monopetalum grown on soil polluted with Cd and Pb irrigated at different salinities, and the second with commonly cultivated ornamental L. monopetalum grown on soil polluted with Cd irrigated also at different salinities. The data revealed that wild L. monopetalum is a Cd and Pb tolerant plant able to accumulate at least 100 ppm of cadmium in its shoots without showing any significant decrease in terms of biomass production, chlorophyll content or water content suggesting that it could be an accumulator of Cd. Pb above-ground accumulation was kept at low levels with the majority of Pb localized in the roots. On the other hand, contrasting results were obtained for ornamental L. monopetalum which although it was found to be also Cd tolerant, Cd accumulation in its tissues was kept at significantly lower levels especially compared to that of the wild ecotype. In addition for ornamental L. monopetalum salinity did not have a positive effect on Cd accumulation and translocation as observed in the wild type and in other halophytes. Analysis of the salt excretion crystals on the leaf surface confirmed that wild and cultivated ornamental L. monopetalum excrete cadmium and lead through their salt glands as a possible metal detoxification mechanism, although the amount excreted by the ornamental L. monopetalum is significantly less.  相似文献   

2.
Salt marshes are ecosystems subjected to a variety of environmental stresses like high salinity, water deficit, intense radiation or high temperatures. Field measurements were conduced in two halophyte species, Atriplex portulacoides L. and Limoniastrum monopetalum L., in the Reserva Natural do Sapal de Castro Marim, to compare their physiological response, i.e., water potential (ψ), net photosynthetic rate (A), stomatal conductance (gs) under natural conditions. Both species demonstrated marked variations in ψ throughout the year, with very low values in the summer, the period of higher salinity, drought and temperature. Deficit water potential (Δψ = ψmidday − ψpredawn) was lower in the summer than in other seasons in A. portulacoides but not in L. monopetalum. The highest values for A and gs in L. monopetalum were observed in autumn and for A. portulacoides in winter, presenting both lowest values in spring and summer. Amax was particularly high for L. monopetalum than for A. portulacoides in summer and autumn, despite gsmax was similar in both species. Diurnal pattern of A and gs were similar in both species, with higher values in the morning, decreasing throughout the day.  相似文献   

3.
Changes in phenolic composition and biological activities were investigated in different Limoniastrum monopetalum L. organs. For that, 80% aqueous acetone extracts were used to estimate total phenolic contents and their antioxidant activities were evaluated using DPPH· and O2·− radical scavenging activities and reducing power. The efficiency of organ extracts was tested against human pathogen strains. Ultimately, acid hydrolysis of all organs was subjected to RP-HPLC for phenolic identification. Results showed that flower extracts exhibited the highest polyphenol (65.42 GAE/g DW) and flavonoid (35.36 CE/g DW) contents. Stems were enriched in condensed tannin content (21.4 mg CE/g DW) and displayed the best antiradical activities and the highest reducing power. Besides, stem and gall extracts showed the highest efficiency against pathogenic bacteria as compared with those of flower. Concerning the antifungal test, a slight activity was found in gall extracts. The RP-HPLC showed a difference in phenolic compounds that varied as function of organ. In fact, the major phenolic compound varied as function of organ. Results suggest that L. monopetalum could be a promising source of biomolecules for therapeutic and nutraceutical industries and the difference between organs may be related to their physiological role.  相似文献   

4.
The subtropical grapsid crab Percnon gibbesi (H. Milne Edwards, 1853) is one of the most recent alien decapods found in the Mediterranean, where it was discovered at Linosa (Pelagie Islands, Sicily Strait) in summer 1999. At present, the invasion of this species has been recorded in several other insular localities. We studied the feeding habits of the crab in an attempt to understand its success in the Mediterranean. The morphological characteristics of the chela, the feeding adaptations of the gastric mill and the analysis of stomach contents indicate that P. gibbesi is a strictly herbivorous species, a characteristic not shared with any other large-sized infralittoral Mediterranean crab.  相似文献   

5.
The present study consists in evaluating the inter- and intraspecific variability of phenolic contents and biological capacities of Limoniastrum monopetalum L. and L. guyonianum Boiss. extracts. Ultimately, they were subjected to HPLC for phenolic identification. Results showed a great variation of phenolic content as function of species and localities. In fact, L. guyonianum extracts (El Akarit) contained the highest polyphenol (57 mg GAE g?1 DW), flavonoid (9.47 mg CE g?1 DW) and condensed tannin contents (106.58 mg CE g?1 DW). These amounts were accompanied by the greatest total antioxidant activity (128.53 mg GAE g?1 DW), antiradical capacity (IC50 = 4.68 μg/ml) and reducing power (EC50 = 120 μg/ml). In addition, L. monopetalum and L. guyonianum extracts exhibited an important and variable antibacterial activity with a diameter of inhibition zone ranging from 6.00 to 14.83 mm. Furthermore, these extracts displayed considerable antifungal activity. L. monopetalum extracts (Enfidha) showed the strongest activity against Candida glabrata and C. krusei with a diameter exceeding 12 mm. The phytochemical investigation of these extracts confirmed the variability of phenolic composition, since the major phenolic compound varied as a function of species and locality. These findings suggest that these two halophytes may be a new source of natural antioxidants that are increasingly important for human consumption, as well as for agro-food, cosmetic and pharmaceutical industries.  相似文献   

6.
Abstract

The author reports the results of the herborizations carried out on the island Piana (northeastern Sardinia) located between Cape Ceraso and Cape Coda Cavallo. The flora consists of 250 entities distributed in 154 genera, inclusive of 54 families. The author gives information regarding the mail features of the vegetal coverage, and points out the presence of two species: Limonistrum monopetalum (L.) Boiss. and Omithoga-lum arabicum L., which are extremely rare in the little islands.  相似文献   

7.
8.
Use of Capsicum frutescens L. by the Indigenous Peoples of Taiwan and the Batanes Islands. The local nomenclature, use, and distribution of C. frutescens among indigenous peoples in Taiwan and the Batanes Islands were studied. Among Taiwanese indigenous peoples, the distribution, frequency of use, and importance of C. frutescens were found to increase with decreasing latitude, which appears to have affected the local names of Capsicum and C. frutescens. The local name for Capsicum in the Batanes Islands—“sili”—is used by several indigenous peoples in Taiwan, suggesting that Capsicum was brought from the south to the north. Indigenous peoples in Taiwan and the Batanes Islands used C. frutescens fruits as condiments, medicines, ornaments, or for ritual uses; also, they used its leaves for soup. A complex of both green and yellowish-green types possessing ShDH-B was introduced from Indonesia into the Batanes Islands and Taiwan, and later only the type with yellowish-green immature fruit was introduced to the Ryukyu Islands under the bottleneck effect.  相似文献   

9.
Abstract

We have completed a taxonomic revision of the New Zealand marbled skink (Cyclodina oliveri) species complex. Morphological analyses and mitochondrial sequence data (ND2, ND4, Cytochrome b; Total 1933 bp) are used to describe a new taxon (commonly known as the “Mokohinau” skink) and redefine C. oliveri. The morphological and molecular data indicate that C. oliveri is distributed on the Poor Knights Islands, Mercury Islands and Aldermen Islands. The new species is restricted to the Mokohinau Islands, Hen and Chickens group, Little Barrier Island and Great Barrier Island. Our data demonstrate that there is no support for the separation of the Poor Knights Islands population of C. oliveri from those on the Mercury Islands and Aldermen Islands. The genetic data indicate that C. whitakeri is part of the C. oliveri species group. Divergence time estimates indicate that the C. oliveri species complex diverged during the late‐Miocene, with further divergences among island groups in C. oliveri including the origin of the new taxon during the late‐Pliocene and mid‐Pleistocene. We present a diagnostic key for Cyclodina.  相似文献   

10.
The coastal shrub Limoniastrum monopetalum is capable of growth in soil containing extremely high concentrations of heavy metals. A greenhouse experiment was conducted in order to investigate the effects of a range of Zn concentrations (0–130 mmol l−1) on growth and photosynthetic performance, by measuring relative growth rate, total leaf area, plant height, gas exchange, chlorophyll fluorescence parameters and photosynthetic pigment concentrations. We also determined the total zinc, nitrogen, phosphorus, sulphur, calcium, magnesium, sodium, potassium, iron and copper concentrations in the plant tissues. The study species demonstrated hypertolerance to Zn stress, since survival was recorded with leaf concentrations of up to 1700 mg Zn kg−1 dry mass when treated with 130 mmol Zn l−1. L. monopetalum exhibited little overall effects on photosynthetic function at Zn levels of up to 90 mmol l−1. At greater external Zn concentration, plant growth was negatively affected, due in all probability to the recorded decline in net photosynthetic rate, which may be linked to the adverse effect of the metal on photosynthetic electron transport. Growth parameters were virtually unaffected by leaf tissue concentrations as high as 1400 mg Zn kg−1 dry mass thus indicating that this species could play an important role in the phytoremediation of Zn-polluted areas.  相似文献   

11.
In July 2003, the finding of a newly settled population of Siganus luridus at Linosa Island (Sicily Strait, Mediterranean Sea) gave us the unusual opportunity to examine the reproductive condition of a Lessepsian migrant during early phases of colonization. Aspects of gonad morphology, fecundity, atresia and oocyte dynamics were investigated by using 43 pioneer specimens collected in concomitance with their first record in the Pelagie Islands. Ovarian development was consistent with the group‐synchronous type, and testicular organization was of the unrestricted spermatogonial testis type, with cystic spermatogenesis. Both males and females had reached final stages of gonad maturation. The rates of follicular atresia were moderate: out of 17 adult females, 10 individuals did not present atretic oocytes; six exhibited <15.1% of secondary growth phase (SGP) oocytes in α‐atresia, while one female presented 45.7% of SGP in α‐atresia. Fecundity estimates did not diverge from what was observed in a reference population along the Lebanese coast. Absolute fecundity ranged from 115 739 to 740 433 oocytes per female (16.5–24.5 cm LT). Relative fecundity ranged from 1239 to 3162 oocytes g−1, with a mean of 1885 ± 868 oocytes g−1. Our observations indicated that these early settled siganids are reproductively active at Linosa and suggested the forthcoming of self‐maintaining populations across the central Mediterranean area.  相似文献   

12.
Abstract

Preliminary studies on the marine phythobenthic communities in the Straits of Sicily and adjacent islands. — The results of algological researches carried out by the Gruppo di Algologia of the S.B.I. in the Straits of Sicily and adjacent islands are reported. 288 species have been collected, 275 of which have been identified: 160 were Rhodophyta, 62 Phaeophyta, 32 Chlorophyta, 16 Cyanophyta and 2 Angiospermae. The vegetational research leads to the following conclusions: 1 - the harbour areas (Pantelleria, Malta: loc. 1 and 11) show a nitrophile vegetation, particulary near La Valletta where an almost pure population of Pterocladia pinnata is found; 2 - there are important biogeographical differences between Pelagie islands (Lampedusa, Linosa) and Pantelleria. In fact the former ones have an algal flora composed mostly of eastern mediterranean species, whilst the latter shows strong affinities with the north-african basin, as is demonstrated by the rich well developed belt of Cystoseira sedoides; 3 - several species of atlantic origin, such as Callophyllis laciniata, Peyssonnelia coriacea, P. inamoena and Castagnea chordariaeformis, have been found on the banks (loc. 3, 6, 7).  相似文献   

13.
Abstract

We describe a new skink species (Oligosoma taumakae sp. nov.) from the Open Bay Islands, New Zealand. This species is diagnosed on the basis of several morphological characteristics, and its specific status is supported by mitochondrial sequence data (ND2, ND4). The new species appears to be most closely related to O. acrinasum, O. infra‐punctatum, O. otagense and O. waimatense. The new taxon appears to be rare and endemic to the island of Taumaka in the Open Bay Islands (off the west coast of the South Island). Predation by a flightless rail (weka, Gallirallus australis), native to New Zealand but introduced to the Open Bay Islands, is a major conservation concern.  相似文献   

14.
Abstract

A new species of the lacazelline brachiopod genus Ospreyella is described from shallow cryptic habitats in Palau, western Caroline Islands and Arnd Atoll, Pohnpei, eastern Caroline Islands, north‐western Pacific Ocean. This new taxon, here named Ospreyella palauensis, and representing the third discovery of a species of Ospreyella from the Indo‐Pacific region, is compared with the other two recently described extant species of the genus, O. depressa Lüter from the Great Barrier Reef, Australia, and O. maldiviana Logan from the Maldive Islands, northern Indian Ocean. An ontogenetic sequence is described for the new species and compared with those previously described for other Holocene lacazellines. Additionally, a study of ontogenetic stages in Thecidellina congregata from Saipan in the Northern Mariana Islands shows early‐stage similarities to those of the new species and other lacazellines. These observations on development in extant forms provide important analogies for comparison with ontogenetic stages in ancestral fossil forms and information which may be useful in reconstructing thecideide phylogenetic history.  相似文献   

15.
ABSTRACT

The results of a floristic study of benthic marine macroalgae on rocky substrata from the Tremiti Islands (Adriatic Sea) are presented. The list of taxa at specific and infraspecific level consists of 226 Rhodophyceae, 59 Fucophyceae and 36 Chlorophyceae. Of these 321 taxa, 147 are newly reported from the Tremiti Islands. Data on the reproductive phenology of each species, and comments on some species of particular interest are also given.  相似文献   

16.
This study dealt with the decomposition and nutrient release from the halophytes Atriplex portulacoides, Arthrocnemum macrostachyum, Limoniastrum monopetalum, and Spartina densiflora, the dominant species in the Castro Marim salt marsh, Portugal. Environmental effects on decomposition were also assessed. The study was carried out for one year using the in situ litterbag technique. S. densiflora showed a lower decomposition rate (k = 0.003 day−1) than the other study species (k = 0.005-0.009). Study species showed similar decomposition patterns, that is, the weight loss mostly occurred during the autumn-winter period (study beginning in November). This indicates that temperature in this period did not hamper the decomposition process. The decomposition rate was positively affected by the initial N concentration (r2 = 0.87, P < 0.05) and negatively by the C:N ratio (r2 = 0.86, P < 0.05) in decomposing materials. At the end of the study, S. densiflora and L. monopetalum, the species with lower initial N concentrations, retained much higher proportion of initial N (89-109%) than the others (5-14%). Also, S. densiflora with the lowest P concentration retained higher proportion of initial P (48%) than the others (5-20%). Release of K and Mg were also slower from S. densiflora and was associated with their initial low concentration in this species. The lowest Mn release was observed from A. macrostachyum and also in relation to the lowest initial concentration. Our study supports the hypothesis that decomposition patterns of marsh species are mostly associated with differences regarding their morphology and chemical composition. Given the higher resistance of S. densiflora to decomposition, its progressive spreading may result in accumulation of organic detritus overtime in invaded salt marshes.  相似文献   

17.
A new West Palaearctic genus Achaiabracon gen. n. with the type species A. aenigmatus sp. n. is described and illustrated from the Greek Islands Crete and Corfu. The position of this genus in the cyclostome group of subfamilies of Braconidae and its possible relation with rhyssaline genera are discussed. A new tribe Achaiabraconini trib. n. is proposed.  相似文献   

18.
《Journal of bryology》2013,35(1):119-125
Abstract

The genus Thamnobryum is reviewed from Macaronesia (excludingthe Cape Verde Islands). In this area there are three species, T. alopecurum (Hedw.) Gang., T. maderense (Kindb.) Hedenäs, comb. nov. and T. fernandesii C. Sérgio. T. fernandesii is only known from Madeira; the other two also occur on the Canary Islands and the Azores. Thamnobryum canariense (Ren. & Card.) Long is transferred to Isothecium, as I. atlanticum Hedenäs, comb. et nom. nov.  相似文献   

19.
Summary

A commented check-list of the tachinid species inhabiting the Canary Islands (Spain) is provided, with special emphasis on hosts species and floral resources. Nine new local records are provided and Cylindromyia rufipes is reported for the first time for the Canary Islands, thus increasing the species number to 52. Zoogeographic analysis of the area revealed that there are differences in chorotype composition among islands, with the easternmost islands being richer in Mediterranean species and poorer in endemics. These differences may be due to ecological differences between the easternmost island and the remaining islands. Relevance regarding influence of tachinid as pollinators is discussed.  相似文献   

20.
ABSTRACT

Four observations of what was probably a single vagrant adult female whitetip reef shark Triaenodon obesus were made at Raoul and Meyer Islands, Kermadec Islands, New Zealand, over a 12 month period in 2014/15. This is the most southerly occurrence of the whitetip reef shark and ambient winter temperatures were close to the assumed thermal minimum for the species. The closest potential source population occurs at Minerva Reefs, about 598?km northwest of Raoul Island.  相似文献   

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