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1.
BackgroundFish are an important source of nutrition for humans. Artisanal fishing plays a fundamental role in Brazil fish production. In Brazil, the unrestrained increase, diffusion, and little importance for environmental causes of other economic activities, such as the agricultural industry, has caused irreparable damage, leading to the contamination of water bodies. Among the countless pollutants that reach water bodies, trace metals are extremely problematic. Here, we evaluated the bioaccumulation and health risk of trace metal contamination in the musculature of the trahira fish (Hoplias malabaricus), collected from two rivers in southeastern Brazil.MethodsDuring the period from May 2017 to November 2019, 90 fish were collected, 45 from each river. River water samples were also taken during the same collection periods. From fish, muscle tissue samples were taken, and together with river water samples, analyzed for the recovery of trace metals (Al, Cr, Mn, Fe, Ni, Cu, As, Cd, and Pb) through the technique of Inductively Coupled Plasma Mass Spectrometry (ICP-MS).ResultsIn general, fish as well as the waters of the Jacaré-Guaçú River had higher concentrations of metals. The elements Al, Cr and Cd stood out from the others analyzed metals for having a hazard index (HQ) above 1 (Al), for being up to 10 times above the concentrations allowed by Brazilian legislation (Cr) and for having a high bioconcentration factor (Cd), indicating a biomagnification process through the food chain.ConclusionIn general, trace metal concentrations in the waters and fish of the Jacaré‐Guaçú were higher than in the Jacaré-Pepira, which shows that the Jacaré‐Guaçú is the one that suffers more anthropogenic action between the two rivers. In addition, some elements such as Al, Cr and Cd, due to its high concentrations, should receive some attention as they can pose risks to the health of fish, which can jeopardize the survival of their populations, and especially to humans who use these animals as a food source.  相似文献   

2.
Limited studies have been conducted on atmospheric dust pollution due to high cost of instrumental monitoring and difficulties in associated sampling methods. In this study, the possibility of using leaves of plane tree (Platanus orientalis L.) as a bioindicator of atmospheric pollution was evaluated by determining the composition of heavy elements in both the tree leaves and the atmospheric dust. Plane tree leaves were sampled monthly for 7 consecutive months (May to Nov.; T1–T7) from 21 different sites in the city of Isfahan, central Iran. Atmospheric dust samples were also collected from the same sites on glass trays simultaneously, except for T1. Concentrations of Cu, Fe, Mn, Ni, Pb, and Zn were determined in both the washed (WL) and unwashed leaves (UL) as well as in the atmospheric dust samples. Elemental concentrations in the dust samples deposited on the leaves were determined by subtracting metal concentrations in UL from those in WL. Significant amounts of heavy metals were detected in UL taken from all sites at all the sampling times except for T7 before which time a heavy rain had fallen. Statistically significant correlations were found between the heavy metal concentrations in the atmospheric dust and the dust deposited on the leaves (UL–WL) except for Pb in T4 and T5 sampling times. The spatial distribution maps of heavy metal concentrations in atmospheric dust followed almost the same pattern as those in plant leaf dust. The results showed that plane tree leaves have a great potential for use as an indicator of air pollution for all the heavy metals investigated except for Pb. This passive dust sampling and pollution accumulating method appears to be an easy, inexpensive, and accessible approach for the detection of atmospheric heavy metals.  相似文献   

3.
A floristic survey has been carried out in a peri-urban forest, the Sonian Forest in Brussels, to identify indicator plant species in the herbaceous layer, which could be used as an aid within the framework of a more sustainable management of the forest. Three hundred and seventy two (372) taxa have been identified, 33 of which are non-native (i.e. non-indigenous species regarding the study area, whether invasive or not). Criteria of habitat quality that have been chosen are the species richness, the commonness of the habitat, based on constitutive species, and its invasibility (vulnerability for invasion). On the basis of a comparison of the value of these criteria when each considered (potential indicator) species is present or not, 17 species have been recognised as reliable indicators of at least one of these three criteria. In particular, vegetation types containing either Anthriscus sylvestris, Galeopsis tetrahit or Senecio ovatus were found to be more susceptible to invasion than other habitats. The way to how the predictability of invasions might be effectively used as a management tool is discussed. Furthermore, we found a positive significant correlation (Bonferroni corrected probabilities) between the species richness and luminosity factor (derived from Ellenberg's indices), and the proportion of grassland and wetland species. The species richness was significantly negatively correlated with the proportion of woodland species. An increase in commonness was significantly correlated with a decrease in the proportion of geophytes. The usefulness of these results as an ecological basis for forest management is discussed.  相似文献   

4.
《Ecological Indicators》2008,8(5):454-461
In order to evaluate the dispersal pattern of airborne fluoride emissions, from a single source in the city of Ouro Preto, Brazil, the fluoride impact on some herbaceous plant species was studied using the plants as passive bioindicators. Foliar fluoride contents of eight species collected at different distances from an aluminium smelter were analyzed. The plant species were: Baccaharis dracunculifolia, Bidens pilosa, Borreria verticillata, Calopogonium mucunoides, Erigeron bonariensis, Hedychium coronarium, Ipomoea purpurea and Ipomoea cairica. In all species the fluoride accumulation decreased exponentially with the distance from the emission source. There was specific and distinct variation in fluoride accumulation among the species, a group of high-accumulator species (B. dracunculifolia and Bidens pilosa) and a group of low-accumulator species (I. cairica, H. coronarium and Borreria verticillata). C. mucunoides and E. bonariensis occupied an intermediate position. There was a pattern of plant contamination response during the periods analyzed. The plants nearest to the emission source, between 0.4 km northwest and 1.1 km east, showed fluoride contamination traits in leaves reaching values between 100 and 500 μg g−1. Moreover, fluoride contents higher than 1000 μg g−1 were found in these plants. At the most distant stations, situated 2.9 km northwest and 6 km east from the factory, the fluoride content of the dry matter was less than 10 μg g−1 showing that plants at those distances were submitted to minimum contamination. There were different patterns of tolerance among the species analyzed. While B. dracunculifolia accumulated fluoride up to 1500 μg g−1 in dry matter without any signs of injury, Borreria verticillata showed severe necrosis in leaves, but the fluoride content found was not higher than 120 μg g−1.  相似文献   

5.
1. Earthworms (Annelida: Oligochaeta) were sampled on four occasions (spring, summer, autumn and winter) at 14 sites along two transects from a primary lead/ zinc/cadmium smelting works at Avonmouth, UK.
2. Total abundance and biomass of earthworms decreased with proximity to the smelter. No worms were collected from the two sites closest to the factory (<0·6 km) and catches were significantly lower than controls at a further five sites (<3 km).
3. Seasonal composition of sampled communities differed only for summer with lower numbers of individuals and species collected at all sites. Reduced catches in the summer sample is a response to drought.
4. Species richness was lowest at sites close to the factory. For example, worms such as Aporrectodea caliginosa (Savigny) and Allolobophora chlorotica (Savigny) that were dominant at relatively clean sites further from the smelter are absent from the most contaminated soils.
5. Reduced species richness resulted in lower Shannon–Weiner diversity and higher Berger–Parker dominance. Multivariate cluster analysis for spring, summer and winter indicated that sites could be split into three groups based upon relative species composition. In autumn, two clusters were identified.
6. The absence of sensitive species from sites close to the smelting works supports the inclusion of earthworms as a key group in a terrestrial prediction and classification scheme for quantifying the effects of pollutants on soil biodiversity. However, sampling should be carried out in spring or autumn to obtain an accurate picture of community structure.  相似文献   

6.
The present paper aims to perform a screening of native plants growing in Kettara mine-Marrakech (Southern Morocco) for its phytoremediation. Plants and soil samples were collected and analyzed for Pb, Zn, Cu and Cd concentrations at several sites in the mine. The results showed that the soil in the vicinity of Kettara mine is deficient in major elements and contain toxic levels of metals. Spontaneously growing native plants were botanically identified and then classified into 21 species and 14 families. Significant difference was observed among the average concentrations of four heavy metals (Pb, Zn, Cu and Cd) in plants (p ≤ 0.05). Six plants of 21 species namely Hammada scoparia (Pomel) Iljin, Hirschfeldia incana (L.) Lagreze-Fossat, Lamarckia aurea (L.) Moench, Calendula algeriensis Boiss. & Reuter, Aizoon hispanicum L. and Melilotus sulcata Desf. were considered as the best-performing specimens due to their high ability to accumulate multiple metals in their shoots and roots without sustaining toxicity. This was confirmed by the transfer factors generally higher than 1. Using the most common criteria to classify the hyperaccumulator plants, these species can be classified as new accumulator plants of many heavy metals and be potentially used as remediation tools of metal-contaminated sites.  相似文献   

7.
Abstract

Our study had the objective to examine whether the number of forest vascular plants in a forest-poor region may be indicative of total plant species richness and of the number of threatened plant species. We also related forest plant species richness to geological and soil variables. The analysis was based on a regional flora atlas from the Weser-Elbe region in northwestern Germany including incidence data of species in a total of 1109 grid cells (each ca. 2.8 × 2.8 km2). All taxa were classified either as forest or non-forest species. Total species richness in the grid cells ranged from 65 to 597, with a mean value of 308. The number of forest species varied between 20 and 309 (mean 176). Grid cells with or without particular geological units differed in total and forest species richness, with those containing peatland and marshland being particularly species-poor. Indicator value analysis showed that both total and forest species richness in the grid cells were related to soil acidity and nitrogen in a hump-backed manner, with the highest number of species found at moderately low values for nitrogen and at intermediate values of pH. Forest species richness was highly positively correlated with the number of non-forest species and threatened non-forest species. Indicators for high species richness were primarily those species that are confined to closed semi-natural forests with a varied topography and relatively base- and nutrient-rich soils. Grid cells including historically ancient forest exhibited a higher species richness than grid cells lacking ancient forest, indicating the importance of a long habitat continuity for a high phytodiversity. The “habitat coincidence” of high species richness is best explained by similar responses of forest species and species of other habitats to the main environmental gradients. It is suggested that the regional patterns found for the Weser-Elbe region can be transferred also to other forest-poor regions in Central Europe.  相似文献   

8.
A 2-D reference map in pI range 3-10 was constructed for the soluble protein fraction of Phanerochaete chrysosporium growing vegetatively under standard conditions. Functional annotation could be made for 517 spots out of 720 that were subjected to MALDI-TOF-MS analysis, according to the specific accession numbers from the P. chrysosporium genomic database. Further analysis of the data revealed 314 distinct ORFs, 118 of which yielded multiple spots on the master gel. Functional classification of the proteins was made according to the eukaryote orthologous groups defined in the organism's genome website. The functional class of PTMs, protein turnover and chaperones was represented with the highest number (63) of the identified ORFs. Six proteins were assigned to the hypothetical proteins and 29 were predicted to have a signal peptide sequence. Subcellular localization predictions were also made for the identified proteins. Of the protein spots detected on the master gel, 380 were found to be probably phosphorylated and 96 of these matched to the identified proteins. The reference map was efficiently used in the identification of the proteins differentially expressed under cadmium and copper stress. Three new ribosomal proteins as well as zinc-containing alcohol dehydrogenase, glucose-6-phosphate isomerase, flavonol/cinnamoyl-CoA reductase, H+-transporting two-sector ATPase, ribosomal protein S7, ribosomal protein S21e, elongation factor EF-1 alpha subunit were demonstrated as the most strongly induced.  相似文献   

9.
The indicator value (IV) of Macaranga and Mallotus species (Euphorbiaceae) for different types of disturbance in lowland dipterocarp forest was assessed by counting and identifying all individuals of species of these genera taller than 30 cm in 45 (10 m×300 m) plots at nine locations. Twelve Macaranga and nine Mallotus species were found. The main forest disturbance types (primary forest, secondary forest, selectively logged forest, forest burned once, and repeatedly burned forest used for shifting-cultivation) each had their own set of indicator species. The level of disturbance in the forest types was assessed by measuring nine forest structural parameters. The occurrence of Macaranga and Mallotus species was closely related to the level of disturbance in a forest. Most Macaranga species were characteristic of high disturbance levels, while most Mallotus species preferred intermediate to low levels of disturbance. However, both genera had species at both disturbance extremes. Using multiple regression analysis, combinations of Macaranga and Mallotus species were formed and used to predict the separate forest structural parameters and the general level of disturbance of a forest. The Macaranga and Mallotus species could be grouped into (1) primary forest ‘remnant’ species; (2) generalist pioneer species; and (3) high disturbance pioneer species.  相似文献   

10.
The dose responses of 14 wild plant species (two grasses, two legumes, one annual and nine perennial dicotyledons), not usually recognised as weeds, to four herbicides (asulam, glyphosate, MCPA and mecoprop) were measured in glasshouse experiments. Glyphosate was the most toxic; seven of the species tested had EDu, values (measured as shoot dry weight) of < 1.0 μg/plant, compared with only one species for MCPA and mecoprop. Asulam was the least toxic. Results were used to indicate the risk to each species from drift damage. A model of spray drift, based on that developed by Thompson & Ley (1982) for evaporating droplets, was rescaled to allow for field application rates and used to predict the distances travelled by given doses of herbicide. This gave acceptable agreement with reports for drift damage in the field, and predicted that only glyphosate sprayed at the highest recommended concentration might be unsafe to some of the species examined. The two herbicides sometimes used as volatile formulations (MCPA and mecoprop) did not cause damage at the small doses likely to result from exposure to vapour in the field.  相似文献   

11.
In The Netherlands the decline of some phanerogamic species cannot be readily explained from obvious factors such as lowering of the groundwater table, eutrophication or land reclamation. For a number of species the hypothesis was tested that the decline is partly due to air pollution. A two-factor model was made in which decline is accounted for by (a) habitat destruction assessed from topographic maps and (b) air pollution measured as the SO2 95-percentile over the winter period 1978/1979. Effects of both factors were assumed to follow a sigmoid dose-effect curve. For a number of species decline proved to be significantly correlated with air pollution. These are notably species from the syntaxon Violion caninae. A comparison was made with results obtained for epiphytic lichens. It appears that for some phanerogamic species sensitivity is about the same as for moderately sensitive lichens.Nomenclature follows Heukels & van der Meijden (1983).Thanks are due to the Rijksherbarium, for providing some of their unpublished data; and to Ada Groeneveld, for technical assistance.  相似文献   

12.
Question: What is the role of Stipa tenacissima as a nurse plant of the rare and threatened endemic species Haplophyllum bastetanum? Location: Semi‐arid steppe of the Guadix‐Baza basin (SE Spain). Methods: In the two H. bastetanum populations known, we (1) estimated the number of individuals and (2) analysed the influence of the factors ‘site’ (S1 = Hernán Valle, S2 = Alicún), ‘microhabitat’ (inside and below the canopy of the S. tenacissima tussocks vs. open areas), ‘life stage’ (vegetative, reproductive), ‘aspect’ (N, S, E, W, flat) and ‘damage’ (yes or no), in relation to the distribution of individuals and to the height, number of flowers, number of capsules, and edaphic variables. Results: The total number of individuals was estimated at 3135. S. tenacissima was found to have a positive and significant effect on the distribution of H. bastetanum, more pronounced in the sample taken at S2 than S1, where 83.8% of the plants were growing in association with S. tenacissima. Similarly, there were more H. bastetanum individuals that became reproductive inside S. tenacissima tussocks than in the open areas, and H. bastetanum individuals had a greater production of flowers and fruits, especially in the sample taken at S1. Organic carbon, nitrogen, and carbon:nitrogen ratio were related to the height and number of flowers and capsules of the plants. Conclusion: Although new patches were established, with a larger number of individuals, H. bastetanum continues to be Critically Endangered (CR). The results support the hypothesis of the facilitation effect of S. tenacissima on this rare, endemic species. Facilitation of species of interest in conservation is an aspect that has not previously been clearly reported. We propound this important process as a valuable tool for rehabilitation of populations of threatened plant species in conservation biology projects.  相似文献   

13.
Teleocichla preta nov. sp. inhabits the rapids along the Rio Xingu and lower portion of the Rio Iriri. It is the largest species in the genus, reaching 121·3 mm standard length (LS) while others do not reach more than 87·8 mm LS. Teleocichla preta is distinguished from all other species of Teleocichla by the unique blackish (in live specimens) or dark brown (preserved specimens) overall colouration of the body, which masks the faint vertical bars or zig‐zag pattern of blotches on the flanks. Teleocichla preta also has a deeper body and a deep laterally compressed caudal peduncle, unlike any other congener, as well as a stout lower pharyngeal tooth plate bearing molariform teeth on its median area.  相似文献   

14.
The bee genus Chilicola Spinola (Xeromelissinae) is recorded from the State of Bahia, Brazil for the first time, based on a new species of the megalostigma group of the subgenus Hylaeosoma Ashmead. Chilicola (Hylaeosoma) kevani sp. n. is described and figured from males collected in Wesceslau Guimarães, Bahia. The species can be distinguished on the basis of coloration, size, integumental sculpturing, and structure of the hidden metasomal sterna and genitalia. A revised key to the species of the megalostigma group is provided.  相似文献   

15.
A new barbine cyprinid fish, Acrossocheilus multistriatus sp. nov., is described from the Zhujiang River(Pearl River) basin in South China. It is separated from all other barred congeners except A. monticola by its unique coloration pattern of 8–12 vs. 5–7 vertical dark bars on the dorsum and flank. Although 8 vertical black bars are also present in specimens of A. monticola, the new species is distinct from it by having a well-developed(vs. poor-developed) lower lip, with or without a median interruption(vs. with a median interruption which wider than 1/2 mouth width) on lower jaw, the lower jaw entirely covered(vs. uncoverd) by the lower lip, body depth 22.57%–25.22% SL(vs. 25.64%–32.26% SL). Additional characteristices as follows: last simple dorsal-fin ray soft without serration; dark stripes on membranes between dorsal-fin rays; dark stripes absent on membranes between anal fin rays; maxillary barbels longer than eye diameter, extending to posterior edge of eyes.  相似文献   

16.
17.
A new species, Isolepis namaquana Muasya & J.Viljoen, is described and illustrated. It is known from two localities in Namaqualand: near Kamieskroon and at the foot of the Matsikammaberge, where it grows in ephemeral wetlands. The tufted annual species is diagnosed by floral and fruit characters including glume size, bifid stigma and colliculate nutlet surface ornamentation.  相似文献   

18.
Two new species of harpacticoid copepod belonging to the families Ameiridae and Ancorabolidae are fully described and illustrated. Pseudameria signyensis sp. nov. is very similar to P. crassicomis Sars but is distinguished from it by the presence of an extra seta on the inner border of the terminal segment of the endopodite of the fourth swimming leg. Laophontodes macropodia sp. nov. is distinguishable from all other species in the genus by the setal formula of the first four swimming legs but more particularly by the unique shape of the fifth leg. Idyellopsis typica Lang is by far the most abundant harpacticoid inhabiting sublittoral fine sand in Borg Bay, Signy Island, Antarctica. The female of this species is redescribed and the male described and illustrated for the first time.  相似文献   

19.
The first record of two trichomycterid species from the thermal waters of a small stream in Miraflores, north of Potosí, Bolivia is given. The reported species are Trichomycterus therma n. sp. and Trichomycterus tiraquae . The new species differ from all congeners in the possession of thickened transverse skin on the ventral surface of the head. They are further distinguished from all congeners by the following combination of characteristics: presence of spatulate incisiform premaxillary teeth; presence of large and rounded papilla-like structures on trunk of body; continuous segment of the laterosensory canal within the frontal with the presence of a segment between pores 2 and 6; long laterosensory canal with four to six pores; maxilla with a short anterior process that is smaller than the main axis of the bone, and has an anterior orientation; mesethmoid shaft narrower than the width of the lateral cornua; prepelvic length 58·7–61·0% of standard length ( L S); head width 19·1–22·8% of L S; submaxillary barbel length 23·9–37·5% of head length ( L H). Two derived characters, namely the presence of spatulate incisiform premaxillary teeth and large and rounded papilla-like structures, define a monophyletic group within Trichomycterus , comprising T. therma , T. corduvensis and T. tiraquae .  相似文献   

20.
This contribution describes a new species of Litopeltis from Brazil, L. teresopolitensis sp. n., which shows similarities with L. paineirensis Lopes & Oliveira, 2010 and L. ribeiropretano Lopes & Oliveira, 2010. It differs in characters of morphology genitalia and configuration, with the median sclerite bearing microspines on the sclerotic apex. A map showing the geographic distribution of the Brazilian species and a key to males of the other species of the genus are also presented.  相似文献   

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