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21.
Minerals can enter the food chain through industrial and mining activities. Soil-to-vegetable transfer is higher than soil-to-cereal, but human consumption of metals is attributable to balanced diets containing both vegetables and cereals and drinking water. However, the impact of location on intakes of metals from predominantly cereal-based Indian diets is not clear. Hence, the present study was undertaken in selected Agricultural, Industrial, and Coal Mining Areas (AA, IA, CMA) around the Allahabad District in Northern India to compare transfer of toxic metals, Pb, Cd, Cr and essential metals, Fe, Zn, Cu, Co in soil and water to common crops: cereals (rice, wheat, maize) and vegetables (spinach, potato), and to assess Daily Intake of Metal (DIM) and consequent Health Risk Index (HRI). The overall content of all metals, except Cu, in water, soils, and crops followed the pattern CMA > IA > AA. Transfer factors (TFs) followed the sequence spinach > potato > cereals. Quantitatively, however, cereals contribute maximally to a balanced diet, so DIM and HRI were higher from cereals than vegetables. Even though spinach had the highest TFs, cereals contributed maximally to HRI. CMA had the highest metal content so locally grown cereals contributed significantly to intake of both toxic and essential metals.  相似文献   
22.
Green algal communities were investigated in clean and pollution-impacted tundra soils around the large coal mine industrial complex of Vorkuta in the E. European Russian tundra. Samples were collected in three zones of open-cast coal mining with different degrees of pollution-impacted soil transformation. A total of 42 species of algae were found in all zones. The species richness decreased from 27 species in undisturbed zones to 19 species in polluted zones. Under open-cast coal mining impacts the community structure simplified, and the dominant algae complexes changed. Algae that are typical for clean soils disappeared from the communities. The total abundance of green algae (counted together with Xanthophyta) ranged between 100–120 × 103 (cells/g dry soils) in undisturbed zones and 0.5–50 × 103 in polluted zones. Soil algae appear to be better indicators of coal mine technogenic pollution than flowering plants and mosses. Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.  相似文献   
23.
东北老工业基地煤炭矿区环境问题与生态对策   总被引:7,自引:1,他引:6  
在对我国东北老工业基地煤炭矿区环境问题进行分析的基础上,提出了解决该地区煤炭矿区环境问题的生态对策,包括着重强调煤炭矿区的生态可持续发展对于采矿工业的复兴具有重要推进作用,而澳大利亚关于最佳实践的经验对于今后采煤矿区的发展具有重要借鉴意义。推行生态多元综合治理的土地复垦一修复模式是今后煤炭矿区环境保护的方向。  相似文献   
24.
描述了一种产自山东省南部的陶枣煤田和兖州煤田太原组煤核中的鳞木类茎的解剖构造特征.根据叶座的形态,该种茎曾被归入大青山"鳞木"("Lepidodendron"tachingshanense Lee)种,但此次重新仔细研究后转归三点"鳞木"("Lepidodendron",tripunctatum Stock.et Math.)种内.与欧美植物区和华夏植物区已有的具解剖构造的鳞木类茎进行了详细对比,认为与奇木属Diaphorodendron很接近,但叶座的形态和解剖差别较大.此外,当前标本的分枝方式还不清楚,因此,还不能将当前标本归入奇木属内.当前标本与奇木属的关系及其分类位置有待于今后对更多更好的标本进行深入研究.  相似文献   
25.
龙健  冉海燕 《生态科学》2019,38(2):212-218
对贵阳花溪区麦坪乡煤矿废弃地进行了野外调查, 对该地优势植物和土壤进行了采样, 测定样品As、Cd、Cu、Hg、Pb和Zn的含量, 发现当地优势植物雀稗(Paspalum thunbergii Kunth ex Steud.)地上部分Cu含量达到1058.12 mg•kg-1, 转移系数2.89, 富集系数16.07。研究了雀稗在铜离子胁迫实验中的根系活力变化和叶绿素浓度变化, 雀稗根系活力随实验进行而逐渐降低, 铜离子浓度为500 µg•mL-1的实验进行到第四周时TTC还原量达到最低值; 叶绿素浓度随着铜离子浓度的增加而缓慢降低, 进一步确认当地土著植物雀稗对铜离子有一定的耐受性。  相似文献   
26.
Two new species ( Neuropteris terminiscus and N. kneuperi ) are described from the Bolsovian ('Westphalian C') of Saarland. N. terminiscus had previously been misidentified as Paripteris pseudograndinioides , but the pinnae are clearly imparipinnate and thus cannot belong to that morphogenus. N. kneuperi had previously been misidentified as Neuropteris obliqua and N. heterophylla , both which appear to be absent from Saar-Lorraine. This is considered further evidence of the distinctive nature of the Westphalian vegetation of the Saar-Lorraine Basin, especially among the seed-plants.  © 2002 The Linnean Society of London , Botanical Journal of the Linnean Society , 2002, 139 , 193–205.  相似文献   
27.
A distinctive kind of anatomically preserved cardiocarpalean ovule is described from the Early Permian Taiyuan Formation of northern China. Ovules are small, have 180° rotational symmetry, and possess variably thick integuments with prominent secretory cavities that may be empty, filled with resinous materials and in several instances appear to contain animal coprolites. Comparisons show that (where known) these features conform to those of Callospermarion undulatum (Neely) Rothwell, to which they are assigned, previously only known from the Pennsylvanian of Euramerica. These fossils represent the first indisputable occurrence of the genus Callospermarion in the Early Permian Cathaysian floras, and show the presence of callistophytalean seed-ferns in this palaeofloristic realm for the first time. These data combined with results from previous investigations now support the Early Permian northern Cathaysian flora including the Taiyuan Formation having evolved from the Late Carboniferous and earliest Permian Euramerican flora, with which it shares far too many generic level similarities for these co-occurrences to be coincidental. Our hypothesis is therefore that the Early Permian flora of the northern Cathaysian realm represents the continued evolution of wetland Euramerican-type coal-swamp floras, and as such is likely to present a model for evolutionarily driven floral change as opposed to the climatically driven floral changes observed in the Euramerican flora after the demise of coal-swamp environments. The distribution of coprolites in and immediately around glandular cavities in this species suggests specialised syndromes of herbivory existed in Early Permian Cathaysian ecosystems, with herbivores preferentially selecting these areas of the ovule integument.  相似文献   
28.
徐州王庄煤矿山西组孢粉植物群及其地层意义   总被引:1,自引:0,他引:1  
徐州王庄煤矿山西组中、下部产有丰富的孢粉化石,保存完好,共计55属132种(包括3新种)2个未定型孢子及1个疑源类未定类型。根据孢粉属种组成及其含量的变化,自下而上分为两套组合:Cyclogranisporites-Gulisporites-Laevigatosporites-Florinites组合(简称组合1)和Calamospora-Gulisporites-Vesiculatisporites-Florinites组合(简称组合2)。根据组合内一些重要分子的地质时限讨论及其与相关组合的对比,将组合1的地质时代归为早二叠世早期,组合2的时代归为早二叠世晚期。文中描述孢子3新种,图示孢子花粉91种。  相似文献   
29.
Algal communities were investigated in two contrasting chronosequences established on reclaimed spoils in the west Bohemian brown coal mining district near Sokolov (Czech Republic) and in the Lusatian lignite mining district near Cottbus (Germany). The Sokolov chronosequence was characterized by tertiary cypric clay substrate, afforestation with Alnus glutinosa (L.) Gaertn., and high pH of deposited spoil material, Cottbus chronosequence by tertiary carboniferous and pyritic sand of extremely low pH ameliorated by fly ash, and afforestation with Pinus sylvestris L. and P. nigra Arnold. A total of 122 species of algae was found in both areas. Although the same species number (80) was identified from Sokolov and Cottbus, both proportion of individual algal groups and species composition were different. Green algae prevailed in both areas, but in Sokolov cyanobacteria and diatoms were also quite diverse, and in younger sites they were also abundant. Total abundance of algae ranged mostly between 104–107 cells/g dry soil, and was one order higher in Cottbus than in Sokolov. Species number was high in young sites, decreased with increasing age, and was the lowest in control forests. In Sokolov, the highest abundance was recorded in the youngest alder plantation. In Cottbus, sludge and compost fertilization used in the youngest pine plantations resulted in rapid formation of visible algal crusts dominated by Klebsormidium crenulatum (Kütz) Lokhorst.  相似文献   
30.
Publicly available databases are analysed to demonstrate their relevance to life cycle inventory for energy production in the Canadian context. Site specific emissions along with sectoral emissions data are combined with production data to construct an energy production model, which has been applied to air emissions. The allocation procedure leads to reasonable results for coal, natural gas and electricity. The detailed allocation of the inventory among petroleum co-products is outside the scope of this study as it requires incorporating knowledge of physical relationship (unit process) or using economic data.  相似文献   
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