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61.
Egg shell thickness, egg volume, clutch size and hatching success of Parus major and Ficedula hypoleuca were studied at 14 study sites around a copper smelter complex in Harjavalta, south-west Finland, in 1991–1993. In 1991–1992 unhatched eggs were collected to measure shell quality. F. hypoleuca was more susceptible to pollutants than P. major, the response of which was weaker in all aspects studied. Egg shells of F. hypoleuca were about 17% thinner and eggs were about 8% smaller in volume near the factory than at a distance of 10 km. The clutch size of F. hypoleuca was significantly smaller and hatching success markedly lower at a study site next to the factory complex than at all other sites. In P. major, variation in shell thickness and egg volume was not significantly related to the distance from the pollution source. Clutch size and hatching success of P. major did not significantly differ among study sites, although the trend in hatching success was in the same direction as in F. hypoleuca. Clutches of both species contained less shell material and both species had more nests without eggs near the factory than further away. The surface structure of the eggshells was studied by scanning electron microscope. Especially in F. hypoleuca, the egg shell surface was more rough and porous near the factory. The roles of Ca and heavy metals in shell thinning are discussed. 相似文献
62.
Surface soil (0–20 cm) samples were collected from four chronological sequences of wetlands (i.e., >50-yr-old wetlands, 40-yr-old wetlands, 30-yr-old wetlands and 10-yr-old wetlands) in the Yellow River Delta of China in May and June of 2007. Total contents of Al, As, Cd, Cr, Cu, Ni, Pb and Zn were determined using inductively coupled plasma atomic absorption spectrometry (ICP-AAS) to investigate the levels, sources and toxic risks of heavy metals in these wetlands. Our results showed an increasing trend for Pb, Cu and Zn along the wetland-forming chronosequence although their pollution levels were low. Both As and Cd exhibited significant enrichment due to their high enrichment factor (EF) values (EF > 5), especially in older wetlands (i.e., >50-yr-old and 40-yr-old wetlands), whereas other heavy metals were minimally or moderately enriched in this region. The results of principal component analysis showed that 83.09% of total variance based on eigenvalues (eigenvalue > 1) could be explained by three principal components (PCs) in four wetlands. The source of Al, Cu, Pb and Zn was different from Cd, Cr and Ni. According to the sediment quality guidelines (SQGs) of China, soil samples in the younger wetlands, especially the 10-yr-old wetlands, were moderately polluted by As, Cd and Ni. According to the SQGs of US EPA, all soil samples were heavily polluted by As and moderately polluted by Ni and soil samples in the older wetlands were moderately polluted by Cr. However, with the exception of As and Ni, the contents of other heavy metals in the four wetlands did not exceed the probable effect level (PEL) values. As, Cd and Ni were identified as heavy metals of primary concerns in four wetlands, Cr were of moderate concern in older wetlands, and Pb, Cu and Zn should be paid more attention in younger wetland (i.e., 10-yr-old and 30-yr-old wetlands). A new and sensitive toxic risk index (TRI) is developed for the accurate assessment of toxic risk for heavy metals in wetland soils compared with the sum of the toxic units (∑TUs), and As, Cr, Ni and Cd showed higher contributions to TRI. 相似文献
63.
Louise Kiel Jensen Gunnar Pedersen Salve Dahle 《Journal of experimental marine biology and ecology》2006,333(1):71-78
Crustacean zooplankton form the keystone link between primary producers and fish stocks along the Norwegian shelf and in the southern part of the Barents Sea. We have established a multi-generation cultivation system for zooplankton in order to perform future experiments on the biological effects of drilling discharges from the offshore petroleum industry. A population of the cold-water species, Calanus finmarchicus, was collected in March 2004 and maintained in a static system of 100 l polypropylene containers through all stages (Eggs-CVI). The population exhibited an average developmental time of 105 days which corresponds to realistic sub-Arctic to Arctic conditions (water temperatures = 5 °C (spring) and 8 °C (late summer)). A series of experiments was performed to examine copepod egg production as a function of different food sources and feeding concentrations. Only minor differences in egg production were observed for C. finmarchicus females fed with varying concentrations of the two diatom species Chaetoceros socialis and Thalassiosira weissflogii. In a separate experiment, the response to food availability was examined over time by tracking egg production and fecal pellet production (used as an indicator of food ingestion). Both hatching success and food ingestion were positively correlated with the food concentrations offered to adult females. Through this work we have demonstrated that C. finmarchicus populations can be maintained in the laboratory through multiple generations. In addition, methods to control egg production through changes in food availability have been established making it feasible to control the start date of exposure experiments or the timing of the collection of eggs to initiate a new generation. 相似文献
64.
Griselda Margarita Rodríguez-Figueroa Evgueni Shumilin Ignacio Sánchez-Rodríguez 《Journal of applied phycology》2009,21(1):19-26
The coastal marine sediments near Santa Rosalía on the eastern coast of the Baja California Peninsula (Mexico) are heavily
polluted by metals due to copper mining and smelting over the past century (up to 1984). The present study compares the accumulation
of metals in the brown seaweed Padina durvillaei from the central segment of the coast of Santa Rosalía (polluted by Co, Cu, Mn and Zn) and from two segments north and south
of the known “hot spot”. The seaweed samples were collected in May and August 2004 and June 2005 at 13 stations located along
the Santa Rosalía mining region. Heavy metal concentrations were measured by instrumental neutron activation analysis (Co
and Fe) directly in dried homogenized subsamples or by flame atomic absorption spectrophotometry (Cd, Cu, Mn, Ni, Pb and Zn)
after complete strong acid digestion of sub-samples. The means and standard deviations of the concentrations in dry tissues
of Padina durvillaei specimens for all the studied metals and stations lie in the following sequence: Cd (3.6 ± 1.6 mg kg−1) < Co (6.5 ± 6.1 mg kg−1) < Pb (7.8 ± 6.2) < Ni (9.96 ± 5.28 mg kg−1) < Cu (53 ± 38 mg kg−1) < Zn (63 ± 43 mg kg−1) < Mn (295 ± 269 mg kg−1) < Fe (2243 ± 2325 mg kg−1). This increase of the average concentrations was statistically significant. Principal Component Analysis showed that Factor
1 (36.46%) displays high positive loadings for Co, Cu, Mn and Zn, reflecting the influence of local anthropogenic pollution
on the seaweed composition, while Factor 2 (26.91%) is important for Co, Fe and Ni and probably corresponds to the adsorption
or accumulation of terrigenous elements of the regional origin, while Factor 3, with a high positive loading for Pb and a
high negative loading for Cd, is probably controlled by local and regional anthropogenic input of Pb and episodic supply of
Cd by local upwellings. The results of ANOVA for each element do not show any significant differences between the average
concentrations for Cd, Fe, Ni and Pb in the seaweed of the three segments, or between the central and southern segments for
Cu, Mn and Zn. Cobalt contents in the seaweed from the northern and central segments are, however, significantly different
from the southern segment. This indicates that element concentrations in Padina durvillaei generally do not follow the drastic increases and gradients of Cu, Co, Mn and Zn contents detected in surface sediments.
The apparent contradiction could be explained by a low geochemical mobility of these metals in the polluted sediments, composed
mainly of stable residues of smelter wastes, with very low content of organic matter usually driving diagenetic mobilization
of some metals into interstitial waters and then to the overlying water. 相似文献
65.
J. M. Tobin C. White Dr. G. M. Gadd 《Journal of industrial microbiology & biotechnology》1994,13(2):126-130
Summary Fungi can accumulate metal and radionuclide species by physico-chemical and biological mechanisms including extracellular binding by metabolites and biopolymers, binding to specific polypeptides and metabolism-dependent accumulation. Biosorptive processes appear to have the most potential for environmental biotechnology. Biosorption consists of accumulation by predominatly metabolism-independent interactions, such as adsorptive or ion-exchange processes: the biosorptive capacity of the biomass can be manipulated by a range of physical and chemical treatments. Immobilized biomass retains biosorptive properties and possesses a number of advantages for process applications. Native or immobilized biomass can be used in fixed-bed, air-lift or fluidized bed bioreactors; biosorbed metal/radionuclide species can be removed for reclamation and the biomass regenerated by simple chemical treatments. 相似文献
66.
North Lake, a small (330 ha. surface area) southwestern U.S.A. cooling water reservoir was found to contain less phytoplankton
production (104.0 mg C m−3 day−1), lower annual mean total organic carbon (3.7 mg l−1) and phytoplankton standing crops (0.9 ml m−3) than other local area reservoirs. Concentrations of inorganic P and N were at or below test detection limits during the
study year 1973–1974.In situ
14C non-filtration primary productivity techniques demonstrated significant (≃13 percent) stimulation of planktonic primary
productivity due to power plant entrainment. Optical counts showed no destruction of entrained phytoplankters. Populations
of Cyanophyta were never dominant, although they frequently bloom in most other local reservoirs. Thermal loading at North
Lake is thought to ultimately depress phytoplankton primary production and standing crop by causing nutrient limitation. 相似文献
67.
G. Nakos 《Plant and Soil》1982,66(2):271-277
Summary The Thriasian Plain near Athens in Greece is a site of concentrated industrial development. Total concentrations of Pb, Cd and extractable SO4
2– in surface soil samples collected from this area, were found to be, respectively, 2–7, 6–34 and 2–20 times higher than those in similar soil samples from parts of the country remote from industrial activity.Total concentrations of Pb, Cd, Zn, Cr and S in samples of olive leaves from the same area were found to be, respectively, 4–40, 3–10, 3–9, 2–6 and 17–21 times higher than those found in samples of olive leaves from rural sites. Leaves of cabbages growing in the area contained between 0.82 and 40 g/g (wet weight) of Pb.Addition of Cd, Ni and Cu to a calcareous potted soil at concentrations of 100, 200 and 200 ppm increased the concentrations of the metals in the needles of Aleppo pine (Pinus halepensis) seedlings to 4.5, 3.5 and 10 ppm, respectively, after 7 months growth in the nursey. 相似文献
68.
Santosh?Kumar?SarkarEmail author Asokkumar?Bhattacharya Sankar?Giri Badal?Bhattacharya Dipak?Sarkar Dulal?Chandra?Nayak Asish?Kumar?Chattopadhaya 《Wetlands Ecology and Management》2005,13(1):55-67
Annelida constitute a dominant functional component in soft-bottom macrobenthic communities and reveal a wide range of adaptability to different marine and coastal habitats. Analyses in different polychaete assemblages and their responses to habitat conditions reflect the biological effects of marine pollution and habitat disturbance. The present study is designed to study colonization and community structure of polychaetes in two ecologically distinct locations of the Sundarban Biosphere Reserve on the northeast coast of India. Polychaete assemblages are characteristically different at the two sites in the extreme northern (Ghusighata) and southern (Gangasagar) portions of the Biosphere Reserve. Levels of heavy metals in polychaete body tissues also reveal interspecific and regional variations. The predominant polychaete fauna exhibited a distinct and unique assemblage of two types: (i) Mastobranchus indicus – Dendronereides heteropoda in the sewage-fed substratum at Ghusighata and (ii) Lumbrinereis notocirrata – Ganganereis sootai – Glycera tesselata at Gangasagar at the mouth of the Hugli estuary where chronic anthropogenic stress and contamination with agricultural and industrial effluents occur. The faunistic composition of polychaetes and their potential for the accumulation of heavy metals from the ambient medium are distinctly different. The study demonstrates that textural composition of the sediments, together with hydrodynamic and geotechnical properties, seem to have the greatest control to quantify the differences of the polychaete community in the two study stations. An in-depth comparative study of polychaete community structure at multiple spatial scales is strongly recommended for future environmental impact assessment in this fragile environment. 相似文献
69.
70.
本研究以水培的烤烟给予不同浓度的Cd、Pb及其复合物处理10d后的烟叶为材料,分析了烟叶过氧化氢酶、硝酸还原酶的活性变化,测试了烟叶可溶性糖含量的变化情况,通过透射电子显微镜观察到了Cd和Pb对烟地肉细胞亚显微结构的改变,特别是对叶绿体、线粒体和细胞核结构的损伤情况进行了详细观察。并探讨其毒害机理。研究结果表明:1)烟叶过氧化氢酶的活性剧烈地被Cd抑制;而随着Pb浓度的增加,其活性则表现为先增加后 相似文献