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1.
This study examined the mercury concentration in the Grisette Amanita vaginata Fr. and soil below the fruiting bodies collected between 2000 and 2008 from the wild at seven distant sites across Poland. The Hg content in samples was determined by cold atomic absorption method (CV-AAS) at a wavelength of 253.7 nm. Mean Hg contents varied from 0.096 ± 0.052 to 0.48 ± 0.13 mg kg?1 dry matter (dm) in caps (range, 0.043–0.73 mg kg?1), from 0.047 ± 0.02 to 0.23 ± 0.07 mg kg?1 dm (range, 0.028–0.47 mg kg?1) in stipes, and in underlying soil were from 0.035 ± 0.018 to 0.096 ± 0.036 mg kg?1 dm (range, 0.017 to 0.16 mg kg?1). The median Qc/s values ranged from 1.2 to 2.2 (mean 1.2 ± 0.4 to 2.1 ± 0.5) indicating that Hg content in stipes was generally lower than in caps. This mushroom species has some potential to bioconcentrate Hg in the fruiting bodies, as the values of the bioconcentration factor (BCF) varied for the sites between 1.2 ± 0.6 to 11 ± 5 for caps and 0.61 ± 0.26 to 7.4 ± 3.9 for stipes. Also available literature data on Hg in A. vaginata are reviewed and discussed.  相似文献   

2.
This paper reports the results of the study of Hg contents of four species of Boletus mushroom (Boletus reticulatus Schaeff. 1763, B. pinophilus Pilát & Dermek 1973, B. impolitus Fr. 1838 and B. luridus Schaeff. 1774) and the surface soils (0–10 cm layer, ~100 g) samples beneath the mushrooms from ten forested areas in Poland and Belarus by cold-vapour atomic absorption spectroscopy. The ability of the species to bioconcentrate Hg was calculated (as the BCF) while Hg intakes from consumption of these mushroom species were also estimated. The median Hg content of the caps of the species varied between 0.38 and 4.7 mg kg?1 dm; in stipes between 0.13 and 2.5 mg kg?1 dm and in the mean Hg contents of soils varied from 0.020 ± 0.01 mg kg?1 dm to 0.17 ± 0.10 mg kg?1 dm which is considered as “background” Hg level. The median Hg content of caps of B. reticulatus and B. pinophilus were up to 4.7 and 3.6 mg kg?1 dm, respectively, and they very efficiently bioaccumulate Hg with median BCF values of up to 130 for caps and 58 for stipes. The caps and stipes of these mushrooms if eaten will expose consumer to elevated dose of total Hg estimated at 1.4 mg for caps of Boletus reticulatus from the Kacze ??gi site, which is a nature reserve area. Nevertheless, the occasional consumption of the valued B. reticulatus and B. pinophilus mushrooms maybe safe.  相似文献   

3.
The aim of the study was to estimate copper (Cu) accumulation efficiency in whole-fruiting bodies of 18 edible and non-edible wild growing mushrooms collected from 27 places in the Wielkopolska Voivodeship. Mushrooms were collected each time from the same places to estimate the diversity in Cu accumulation between tested mushroom species within 3 consecutive years of study (2011–2013). The study results revealed various accumulation of Cu in the whole-tested mushroom fruiting bodies. The highest mean accumulation of Cu was observed in Macrolepiota procera (119.4 ± 20.0 mg kg?1 dm), while the lowest was in Suillus luteus and Russula fellea fruiting bodies (16.1 ± 3.0 and 18.8 ± 4.6 mg kg?1 dm, respectively). Significant differences in Cu accumulation between mushroom species collected in 2011 and in the two following years (2012 and 2013) were observed. The results indicated that sporadic consumption of these mushrooms was not related to excessive intake of Cu for the human body (no toxic influence on health).  相似文献   

4.
Intensive agricultural land use imposes multiple pressures on streams. More specifically, the loading of streams with nutrient-enriched soil from surrounding crop fields may deteriorate the sediment quality. The current study aimed to find out whether stream restoration may be an effective tool to improve the sediment quality of agricultural headwater streams. We compared nine stream reaches representing different morphological types (forested meandering reaches vs. deforested channelized reaches) regarding sediment structure, sedimentary nutrient and organic matter concentrations, and benthic microbial respiration. Main differences among reach types were found in grain sizes. Meandering reaches featured larger mean grain sizes (50–70 μm) and a thicker oxygenated surface layer (8 cm) than channelized reaches (40 μm, 5 cm). Total phosphorous amounted for up to 1,500 μg?g?1 DW at retentive channelized reaches and 850–1,050 μg?g?1 DW at the others. While N-NH4 accumulated in the sediments (60–180 μg?g?1 DW), N-NO3 concentrations were generally low (2–5 μg?g?1 DW). Benthic respiration was high at all sites (10–20 g O2 m?2?day?1). Our study shows that both hydromorphology and bank vegetation may influence the sediment quality of agricultural streams, though effects are often small and spatially restricted. To increase the efficiency of stream restoration in agricultural landscapes, nutrient and sediment delivery to stream channels need to be minimized by mitigating soil erosion in the catchment.  相似文献   

5.
The aim of this study was to evaluate short-term concentration and time effects of cadmium on Kandelia obovata (S., L.) Yong root exudation, thereby evaluating and predicting the ecophysiological effects of mangrove to heavy metals at the root level. Mature K. obovata propagules were cultivated in a sandy medium for 3 months, and then six concentrations of Cd (0, 2.5, 5, 10, 20, and 40 mg L?1) were applied. After exposure time of 24 h and 7 days, respectively, the root exudates of K. obovata were collected and low molecular weight organic acids (LMWOAs) and amino acids of which were analyzed. In addition, we measured glutathione, soluble protein content, and Cd concentration in the plant. We found 10 and 15 types of LMWOAs and amino acids in root exudates of K. obovata with total concentrations ranging from 29.54 to 43.08 mg g?1 dry weight (DW) roots and from 737.35 to 1,452.46 ng g?1 DW roots, respectively. Both of them varied in quality and quantity under different Cd treatment strengths and exposure times. Oxalic, acetic, l-malic, tartaric acid, tyrosine, methionine, cysteine, isoleucine, and arginine were dominant. Both LMWOAs and amino acids excreted from K. obovata roots play a key role in Cd toxicity resistance. The responsiveness of amino acids was less than that of LMWOAs. We suggest that the ecological effect of root-excreted free amino acids in the rhizosphere is mainly based on the role of nutrients, supplemented with detoxification to heavy metals.  相似文献   

6.
The mushroom Macrocybe gigantea collected from the native stands in the Yunnan Province of China can be considered a species that efficiently bioconcentrates mercury (Hg) because the values of the bioconcentration factor (BCF) calculated for this element were well above unity, i.e., for caps, the BCF ranged from 4.8 to 24 and, for stipes, from 3.6 to 18. The Hg content of the composite samples of caps of the fruit bodies collected in the wild ranged from 0.48 to 1.78 mg kg?1 dry matter and of stipes from 0.36 to 1.70 mg kg?1 dry matter, whereas 0.37 and 0.25 mg kg?1 dry matter were observed for farmed specimens. M. gigantea, because of a large biomass of the fruit bodies that emerge in a cluster, is an important food item in Yunnan, but knowledge on mineral composition and content of this species is largely absent. This study estimated the lifetime average daily dose intake of Hg through mushroom as well as the incremental lifetime cancer risk and non-cancer health hazard to consumers of this mushroom.  相似文献   

7.
This investigation was performed to determine the effect of physicochemical soil properties on penoxsulam, molinate, bentazon, and MCPA adsorption–desorption processes. Four soils from Melozal (35° 43′ S; 71° 41′ W), Parral (36° 08′ S; 71° 52′ W), San Carlos (36° 24′ S; 71° 57′ W), and Panimavida (35° 44′ S; 71° 24′ W) were utilized. Herbicide adsorption reached equilibrium after 4 h in all soils. The Freundlich L-type isotherm described the adsorption process, which showed a high affinity between herbicides and sorption sites mainly because of hydrophobic and H-bonds interaction. Penoxsulam showed the highest adsorption coefficients (4.23 ± 0.72 to 10.69 ± 1.58 mL g?1) and were related to soil pH. Molinate showed Kd values between 1.72 ± 0.01 and 2.3 ± 0.01 mL g?1and were related to soil pH and organic matter, specifically to the amount of humic substances. Bentazon had a high relationship with pH and humic substances and its Kd values were the lowest, ranging from 0.11 ± 0.01 to 0.42 ± 0.01 mL g?1. MCPA Kd ranged from 0.14 ± 0.02 to 2.72 ± 0.01 mL g?1, however its adsorption was related to humic acids and clay content. According to these results, the soil factors that could explain the sorption process of the studied herbicides under paddy rice soil conditions, were principally humic substances and soil pH. Considering the sorption variability observed in this study and the potential risk for groundwater contamination, it is necessary to develop weed rice management strategies that limit use of herbicides that exhibit low soil adsorption in areas with predisposing conditions to soil leaching.  相似文献   

8.
The mass concentration of carbonaceous species, organic carbon (OC), and elemental carbon (EC) using a semicontinuous thermo-optical EC-OC analyzer, and black carbon (BC) using an Aethalometer were measured simultaneously at an urban mega city Delhi in Ganga basin from January 2011 to May 2012. The concentrations of OC, EC, and BC exhibit seasonal variability, and their concentrations were ~2 times higher during winter (OC 38.1?±?17.9 μg m?3, EC 15.8?±?7.3 μg m?3, and BC 10.1?±?5.3 μg m?3) compared to those in summer (OC 14.1?±?4.3 μg m?3, EC 7.5?±?1.5 μg m?3, and BC 4.9?±?1.5 μg m?3). A significant correlation between OC and EC (R?=?0.95, n?=?232) indicate their common emission sources with relatively lower OC/EC ratio (range 1.0–3.6, mean 2.2?±?0.5) suggests fossil fuel emission as a major source of carbonaceous aerosols over the station. On average, mass concentration of EC was found to be ~38 % higher than BC during the study period. The measured absorption coefficient (babs) was significantly correlated with EC, suggesting EC as a major absorbing species in ambient aerosols at Delhi. Furthermore, the estimated mass absorption efficiency (σabs) values are similar during winter (5.0?±?1.5 m2 g?1) and summer (4.8?±?2.8 m2 g?1). Significantly high aerosol loading of carbonaceous species emphasize an urgent need to focus on air quality management and proper impact assessment on health perspective in these regions.  相似文献   

9.
The aim of the study was to evaluate the possibility of supplementation with inorganic forms of selenium (Na2SeO4 and Na2SeO3) in concentrations of 0, 0.1, 0.2, 0.4, 0.6, 0.8, 1.0 and 1.5 mM of three medicinal mushroom species: Agrocybe aegerita, Hericium erinaceus and Ganoderma lucidum. Tested mushroom species grew in Se additions of 0–0.6 mM (A. aegerita and H. erinaceus), while growth of G. lucidum bodies was observed for 0–0.8 mM. For the latter mushroom species, the total Se content was the highest. Content of Seorg was diverse; for control bodies it was the highest for G. lucidum (only organic forms were present), lower for A. aegerita (84% organic forms) and the lowest for H. erinaceus (56% organic forms). Accumulation of Se(IV) was generally significantly higher than Se(VI) for all tested mushroom species. There was no significant decrease of A. aegerita or G. lucidum biomass with the exception of G. lucidum bodies growing under 0.8 mM of Se species addition (15.51 ± 6.53 g). Biomass of H. erinaceus bodies was the highest under 0.2 (197.04 ± 8.73 g), control (191.80 ± 6.06 g) and 0.1 mM (185.04 ± 8.73 g) of both inorganic salts. The addition to the medium of Se salts brought about macroscopic changes in the fruiting bodies of the examined mushrooms. Concentrations exceeding 0.4 mM caused diminution of carpophores or even their total absence. In addition, colour changes of fruiting bodies were also recorded. At Se concentrations of 0.4 and 0.6 mM, A. aegerita fruiting bodies were distinctly lighter and those of H. erinaceus changed colour from purely white to white-pink.  相似文献   

10.
The aim of the study was to compare accumulation efficiency of Al, Ba and nutritional elements (Ca, Fe, K, Mg, Mn, Na) exhibited by six edible mushrooms collected in particular regions of Poland during the last 20 years. The studied mushroom species were Boletus edulis, Cantharellus cibarius, Lactarius deliciosus, Leccinum aurantiacum, Suillus luteus and Xerocomus badius. The highest and the lowest concentrations of the elements in tested mushroom species were 11 – 410, 34 – 337, 16785 – 34600, 140 – 607, 12 – 75 and 16 – 143 mg kg?1d.m., respectively. The highest average concentrations of Al, Mg and Mn were observed in Suillus luteus fruiting bodies, while for Ba, Ca, K and Na it was in Lactarius deliciosus. BCF >1 was found for K and Mg in all tested mushroom species and additionally for the highest Ca and Na concentrations of all tested mushroom species except for C. cibarius and S. luteus, respectively. For the other tested elements (Al, Ba, Fe and Mn) BCF values < 1 were recorded.  相似文献   

11.
The content of arsenic (As) in mushrooms can vary depending on the concentration level of this metalloid in the soil/substrate. The present study evaluated the content of arsenic in Boletus badius fruiting bodies collected from polluted and non-polluted sites in relation to the content of this element in overgrown substrate. It was found that mushrooms from the arsenic-polluted sites contained mean concentrations from 49 to 450 mg As kg?1 dry matter (d.m.), with the greatest content found for specimens growing in close proximity of sludge deposits (490±20 mg As kg?1d.m.). The mean content of total arsenic in mushrooms from clean sites ranged from 0.03 to 0.37 mg kg?1 It was found that B. badius could tolerate arsenic in soil substrate at concentrations of up to 2500 mg kg?1, at least. In different years of investigation, shifts in particular arsenic forms, as well as a general increase in the accumulation of organic arsenic content, were observed. The results of this study clearly indicate that B. badius should not be collected for culinary purposes from any sites that may be affected by pollution.  相似文献   

12.
ABSTRACT

Lead (Pb), cadmium (Cd), and mercury (Hg) contents in ten species of edible mushrooms in Trako??an, Croatia were determined. In addition, the similarity between the studied species was determined by cluster analysis. The caps and stipes of the fruiting bodies were analysed separately. The analyses were carried out by inductively coupled plasma - optical emission spectrometry (ICP-OES). The greatest mean lead concentrations of 1.91 and 1.60 mg kg ?1 were determined in caps and stipes of Macrolepiota procera. The greatest mean concentrations of cadmium (3.23 and 2.24 mg kg?1) were determined in caps and stipes of Agaricus campestris and of mercury (2.56 and 2.35 mg kg?1) in Boletus edulis. In terms of the anatomical parts of the fruiting body (cap-stipe), a considerably greater concentration of the analysed elements was found in the cap for all mushroom species. According to calculated bio-concentration factors, all the examined species were found to be bio-accumulators of Cd and Hg. On the basis of the accumulation of the studied metals, great similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation was obtained by cluster analysis.  相似文献   

13.
Trichoderma species, the causal agents of green mould disease, induce great losses in Agaricus bisporus farms. Fungicides are widely used to control mushroom diseases although green mould control is encumbered with difficulties. The aims of this study were, therefore, to research in vitro toxicity of several commercial fungicides to Trichoderma isolates originating from Serbian and Bosnia-Herzegovina farms, and to evaluate the effects of pH and light on their growth. The majority of isolates demonstrated optimal growth at pH 5.0, and the rest at pH 6.0. A few isolates also grew well at pH 7. The weakest mycelial growth was noted at pH 8.0–9.0. Generally, light had an inhibitory effect on the growth of tested isolates. The isolates showed the highest susceptibility to chlorothalonil and carbendazim (ED50 less than 1 mg L?1), and were less sensitive to iprodione (ED50 ranged 0.84–6.72 mg L?1), weakly resistant to thiophanate-methyl (ED50 = 3.75–24.13 mg L?1), and resistant to trifloxystrobin (ED50 = 10.25–178.23 mg L?1). Considering the toxicity of fungicides to A. bisporus, carbendazim showed the best selective toxicity (0.02), iprodione and chlorothalonil moderate (0.16), and thiophanate-methyl the lowest (1.24), while trifloxystrobin toxicity to A. bisporus was not tested because of its inefficiency against Trichoderma isolates.  相似文献   

14.
The tissue and organs (muscle, brain, liver, and gill) of four species of freshwater fish from Lake Baiyangdian were analyzed for hexachlorocyclohexanes (HCHs) and dichloro-diphenyl-trichloroethanes (DDTs). The distribution characteristics were analyzed for HCHs and DDTs in various tissue and organs, which determined the health risks for humans. The research results showed that the wet weight content of all HCHs (∑HCHs) ranged from 0.05?~?14.53 ng?g?1, with a mean of 3.47 ng?g?1. The wet weight content of all DDTs (∑DDTs) ranged from ND to 8.51 ng?g?1, with a mean of 2.41 ng?g?1. For the various species of fish, the residual level of ∑HCHs was relatively higher in chub and grass carp and lowest in snakehead. The residual level of ∑DDTs was the highest in snakehead and did not exhibit a significant variance in the other three species. For the various tissues and organs, the contents of HCHs and DDTs were both highest in the fish liver, second highest in the fish gill, and lowest in the fish brain and muscle. Among the four types of isomers, the residual level of γ-HCH was relatively higher, while the residual level of α-HCH was the lowest. The content of p,p′-DDE was significantly greater to other forms of DDT and its isomer. The residual levels of HCHs and DDTs in fish were both below the national standard. However, the carcinogenic risk from the HCHs in parts of the tissue and organs of four fish species in Lake Baiyangdian exceeded the screen value threshold set by USEPA.  相似文献   

15.
Nine metals (Fe, Cu, Mn, Ni, Cd, Pb, Hg, Cr, and Zn) were determined in soil and Digitaria eriantha plants within the vicinity of three coal power plants (Matla, Lethabo, and Rooiwal), using ICP-OES and GFAAS. The total metal concentration in soil ranged from 0.05?±?0.02 to 1836?±?70 μg g?1, 0.08?±?0.05 to 1744?±?29 μg g?1, and 0.07?±?0.04 to 1735?±?91 μg g?1 in Matla, Lethabo, and Rooiwal, respectively. Total metal concentration in the plant (D. eriantha) ranged from 0.005?±?0.003 to 535?±?43 μg g?1 in Matla, 0.002?±?0.001 to 400?±?269 μg g?1 in Lethabo, and 0.002?±?0.001 to 4277?±?201 μg g?1 in Rooiwal. Accumulation factors (A) of less than 1 (i.e., 0.003 to 0.37) at all power plants indicate a low transfer of metal from soil to plant (excluder). Enrichment factor values obtained (2.4–5.0) indicate that the soils are moderately enriched with the exception of Pb that had significant enrichment of 20. Geo-accumulation index (I-geo) values of metals indicate that the soils are moderately polluted (0.005–0.65), except for Pb that showed moderate to strong pollution (1.74–2.53).  相似文献   

16.
Trifolium species, commonly known as clover species, have a cosmopolitan distribution and, as such, are used in many different traditional systems of medicine and consumed by many communities all over the world. In this study, the elemental distribution and nutritional value of five edible Trifolium species, namely, Trifolium africanum, Trifolium burchellianum, Trifolium repens, Trifolium dubium and Trifolium pratense were investigated to evaluate the potential of these plant species to alleviate malnutrition, thereby contributing toward the fight against food insecurity. Trifolium species were found to be a rich alternate source of essential nutrients with concentrations of elements being in decreasing order of Ca > Mg > Fe > Mn > Zn > Se > Cu > Cr > Pb > Ni > Co > Cd > As and with adequate levels of lipids (4.2 to 8.6%), proteins (35.1 to 45.4%) and carbohydrates (26.7 to 47.0%). Trifolium species were found to be rich in Se (contributing greater than 516% toward its RDA) with T. dubium having a concentration of 0.53 mg 10 g?1, dry mass, which is higher than Brazil nuts. T. pratense was found to be the most suitable species for human consumption due to it having low levels of toxic metals (As, Cd and Pb) while being rich in macro- and micro-elements, especially Fe (7.84 mg 10 g?1, dry mass) and Se (0.36 mg 10 g?1, dry mass).  相似文献   

17.
Leccinum scabrum is an edible mushroom common in European regions in the northern hemisphere. Macro and trace mineral constituents such as Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn were studied in L. scabrum and in the top soil collected from the same location underneath soil substratum. The “pseudo-total” and labile (extractable fraction of minerals) were measured to get insight into the levels, distribution between the morphological parts of fruiting bodies, potential for their bioconcentration by mushroom and evaluated for human exposure via consumption of the mushroom. The sampling sites include the Dar?lubska Wilderness, Trójmiejski Landscape Park, Sobieszewo Island, Wdzydze Landscape Park and outskirts of the K?trzyn town in Mazury from the norther part of Poland. Median values of K, Rb and P concentrations in dehydrated L. scabrum were for caps in range 27,000–44,000 mg kg?1, 90–320 mg kg?1 and 6,200–9,100 mg kg?1, and followed by Mg at 880–1,000 mg kg?1, Ca at 48–210 mg kg?1 and Al at 15–120 mg kg?1. The median concentrations of Cu, Fe, Mn and Zn in caps were in range 15–27 mg kg?1 db 38–140 mg kg?1, 5.3–27 mg kg?1 and 130–270 mg kg?1. For Ba and Sr, concentrations on the average were at ~1 mg kg?1, and almost equally distributed between the caps and stipes of the fruiting bodies. L. scabrum mushrooms were low in toxic Ag, Cd, Hg and Pb, for which the median values in dried caps from five locations were, respectively, in range 0.48–0.98 mg kg?1 (cap to stipe index, QC/S, was 2.5–4.1), 1.0–5.8 mg kg?1 (QC/S 2.9–3.8), 0.36–0.59 mg kg?1 (QC/S 1.6–2.7) and 0.20–0.91 mg kg?1 (QC/S 1.2–1.9). Substantial variations in the concentrations of the “pseudo-total” fraction (extracted by aqua regia) or labile fraction (extracted by 20% solution of nitric acid) of the elements determined in forest topsoils were noted between some of the locations examined. The elements K, P, Cd, Cu, Hg, Mn, Na, Rb and Zn can be considered as those which were bioconcentrated by L. scabrum in fruiting bodies, while the rates of accumulation varied with the sampling location.  相似文献   

18.
Sanitary landfill leachates are a complex mixture of high-strength organic and inorganic persistent contaminants, which constitute a serious environmental problem. In this study, trace contaminants present in leachates were investigated by gas chromatography-mass spectrometry and gas chromatography-flame ionization detector before and after a pre-oxidation step using a solar photo-Fenton process. More than 40 organic compounds were detected and identified as benzene (0.09?±?0.07 mg?L-1), trichlorophenol (TCP) (0.18?±?0.12 mg?L-1), phthalate esters (Di-n-butyl phthalate (DBP), Butyl benzyl phthalate (BBP), Di(2-ethylhexyl) phthalate (DEHP)) (DBP: 0.47?±?0.01 mg?L-1; BBP: 0.36?±?0.02 mg?L-1; DEHP: 0.18?±?0.01 mg?L-1), among others. Toluene, pentachlorophenol, dimethyl phthalate, diethyl phthalate, and Di-n-octyl phthalate were never detected in any of the samples. After the photo-Fenton treatment process, TCP decreased to levels below its detection limit, benzene concentration increased approximately three times, and DBP concentration decreased about 77 % comparatively to the raw leachate sample. The solar photo-Fenton process was considered to be very efficient for the treatment of sanitary landfill leachates, leading to the complete elimination of 24 of the detected micropollutants to levels below their respective detection limits and low to significant abatement of seven other organic compounds, thus resulting in an increase of the leachate biodegradability.  相似文献   

19.
Abstract

Fourteen cultivars of bai cai (Brassica campestris L. ssp. chinensis var. communis) were grown in the nutrient solutions containing 0–0.5 μg mL?1 of cadmium (Cd) to investigate genotypic differences in the effects of Cd exposure on the plant growth and uptake and distribution of Cd in bai cai plants. The Cd exposure significantly reduced the dry and fresh weights of roots and shoots, the dry weight ratio of shoot/root (S/R), total biomass, and chlorophyll content (SPAD value). Cd concentrations in bai cai ranged from 13.3 to 74.9 μg g?1 DW in shoots and from 163.1 to 574.7 μg g?1 DW in roots under Cd exposure, respectively. The considerable genotypic differences of Cd concentrations and accumulations in both shoots and roots were observed among 14 bai cai cultivars. Moreover, Cd mainly accumulated in the roots. Cd also caused the changes of uptake and distribution of nutrients in bai cai and under the influence of cadmium, the concentration of potassium (K) decreased in shoot and increased in root. However, the concentrations of magnesium (Mg), phosphorus (P), manganese (Mn), boron (B), and iron (Fe) increased in shoots and decreased in roots. In addition, Cd exposure resulted in an increase in calcium (Ca), sulphur (S), and zinc (Zn) concentrations in both shoots and roots but had no significant effects on the whole uptake of the examined mineral nutrients except for S.  相似文献   

20.
The ecotoxic effects of carbaryl (carbamate insecticide) were investigated with a battery of four aquatic bioassays. The nominal effective concentrations immobilizing 50% of Daphnia magna (EC50) after 24 and 48 h were 12.76 and 7.47 µg L?1, respectively. After 21 days of exposure of D. magna, LOECs (lowest observed effect concentrations) for cumulative molts and the number of neonates per surviving adult were observed at carbaryl concentration of 0.4 µg L?1. An increase of embryo deformities (curved or unextended shell spines) was observed at 1.8 and 3.7 µg L?1, revealing that carbaryl could act as an endocrine disruptor in D. magna. Other bioassays of the tested battery were less sensitive: the IC50-72h and IC10-72h of the algae Pseudokirchneriella subcapitata were 5.96 and 2.87 mg L?1, respectively. The LC50-6d of the ostracod Heterocypris incongruens was 4.84 mg L?1. A growth inhibition of H. incongruens was registered after carbaryl exposure and the IC20-6d was 1.29 mg L?1. Our results suggest that the daphnid test sensitivity was better than other used tests. Moreover, carbaryl has harmful and toxic effects on tested species because it acts at low concentrations on diverse life history traits of species and induce embryo deformities in crustaceans.  相似文献   

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