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21.
The principal objective of this study was to compare bioaccumulative properties of two terrestrial moss species Hylocomium splendens and Pleurozium schreberi from the Kielce area (south-central Poland), using various statistical techniques. Forty-six moss samples from 23 sampling sites located within the city limits were analyzed for 33 trace elements. The results indicated that 17 elements (Ba, Ce, Co, Cu, Eu, Fe, Gd, Hg, La, Mo, Nd, Ni, Pb, Pr, Sm, V, Y) dominated in H. splendens, whereas only three elements (Mn, Sr, Zn) occurred in excessive amounts in P. schreberi. No differences in the distribution pattern of Dy, Er, Ho, Sn, Tb, Th and Yb were observed. The element concentration ratio (PI/Hy) varied from 0.50 to 1.19. For 14 elements (Ce, Co, Cu, Fe, Gd, Hg, La, Mo, Nd, Ni, Pb, Sm, Th, V), PI/Hy < 1; for 4 elements (Cd, Mn, Sr, Zn), PI/Hy > 1; for 7 elements (Ba, Dy, Er, Eu, Pr, Y, Yb), PI/Hy = equalled 1. Czekanowski’s method showed similarities in rare earth element concentrations for both moss species. The cluster analysis exhibited three significant clusters at D link /D max × 100 < 50 for both moss species. Strong positive Spearman correlations between both moss species were recorded for the following pairs:Ba-Ba, Co-Co, Er-Er, Eu-Eu, Gd Gd, Mn-Mn, Ni-Ni, Pb-Pb, Pr-Pr, Sm-Sm, Th-Th, Y-Y, and Yb-Yb. Nonparametric tests (Sign test, Wilcoxon tests) showed statistically significant differences only for Cd, Ce, Co, Cu, Hg, Mo, Ni, Pb and Sr. The scanning electron microscope study of H. splendens and P. schreberi revealed a different morphology of these species with no injuries.  相似文献   
22.
用 Moss Bag 富集研究汞矿附近元素汞的沉降   总被引:3,自引:0,他引:3  
应用MossBag监测元素汞的干湿沉降.结果表明:矿区大气汞浓度200—1135ng·m-3时汞的湿沉降为1700μg·m-2·a-1;干沉降987μg·m-2·a-1.而当距矿区67km,大气汞浓度3.4—4.0ng·m-3时,其干沉降21μg·m-2·a-1,湿沉降33μg·m-2·a-1,湿沉降占总沉降61%—63%,干沉降占37%—39%,元素汞的干湿沉降与距汞源的距离明显相关  相似文献   
23.
The Ozegahara peatland, in the Nikko-Oze National Park in Japan, is ecologically significant because of its oligotrophic environment; it is one of the most strictly preserved areas in the country. The isotope ratio of nitrogen (15N/14N) and carbon (13C/12C) and C/N ratio of peat moss (Sphagnum spp.) and sundew (Drosera rotundifolia) in the peatland were analyzed. The correlation of the isotope ratio with some parameters (sundew population density, number of trapped insects, water level, bog myrtle coverage, and visitor density) was investigated. The nitrogen isotope ratio of sundew showed the most significant covariation with visitor density, where sundew from lunch areas or along busy walkways showed a higher nitrogen isotope ratio. The nitrogen isotope ratio of peat moss covaried, not only with route traffic frequency but also with water level, bog myrtle coverage, and number of trapped insects by sundew, indicating that factors other than the visitor level influence the local nitrogen cycle. This study suggests that the nitrogen imported into the peatland by visitors is a principal factor to be monitored for the maintenance of the natural environment.  相似文献   
24.
A biomonitoring of airborne trace elements was performed in 2006 in Naples urban area through the exposure of devitalised Hypnum cupressiforme for 10 weeks at 4 m height. In one street, the moss was exposed at different heights to assess vertical gradients of element concentrations. Results were compared with those of a 1999 biosurvey. Correlations among Al, Fe and Ti suggested a soil particles contribution to element uptake. Cu, Mo and Fe were related with traffic flows. Long-range transport contributed to Cd, Cu and Mo accumulation in moss at higher heights. As in 1999, the airborne element load was higher in coastal sites, more affected by marine aerosols and traffic. In all sites, contents of Cd, Fe, Pb, Ni and V in moss were remarkably lower than in 1999, indicating a positive effect of actions set up in recent years to reduce the traffic and to improve the city air quality.  相似文献   
25.
Productivity of the moss cover and necromass accumulation in the litter of a sphagnum larch forest have been estimated on the basis of tree age. It has been shown that the total carbon stock in the litter of a 100-year-old stand, including organic matter not destroyed by fire, exceeds the corresponding value for the tree stand itself by more than an order of magnitude. The accumulation of organic matter on the soil surface inhibits the growth of larch. In particular, this factor impairs hydrothermal conditions in the soil and causes a rise of the permafrost table; as a consequence, lower layers of the root system die off.  相似文献   
26.
BACKGROUND, AIMS AND SCOPE: Over the last few years there has been extensive research for new indicators providing information about deposition resulting from road traffic and tunnel experiments received special attention in emission research. Mosses have been used for the estimation of atmospheric heavy metal and PAH depositions for more than three decades, although they were used only a few times for estimating ambient air pollution caused by traffic. In the current study, the suitability of using a moss species for monitoring road traffic emissions inside a tunnel was evaluated. This was a first-time ever attempt to use plants (mosses) as bioindicators in a tunnel experiment. Specifically, two relevant questions were examined: 1) Do mosses accumulate toxic substances derived from road traffic emissions under the extremely adverse conditions which can be found in a tunnel, and 2) Which substances can mainly be attributed to road traffic emissions and therefore be taken as efficient and reliable indicators for motor vehicles? METHODS: For the first time a biomonitor (the moss species Hylocomium splendens (Hedwig) B.S.G.) was used in a road tunnel experiment to analyse emissions from road traffic. Moss samples were exposed for four weeks in wooden frames (size 10 cm x 10 cm), covered by a thin plastic net with a mesh size of 1 cm x 1 cm. 17 elements, mainly heavy metals, and the 16 EPA-PAHs together with coronene were analysed by ICP-AES, AAS and GC-MSD. RESULTS: Enrichment factors, calculated by comparing post-experiment concentrations to those of a background site, were high for most PAHs, especially benzo(g,h,i)perylene (150.7), coronene (134.7), benzo(a)anthracene (125.0), indeno(1,2,3-c,d)pyrene (79.8), chrysene (78.1), pyrene (69.6) and benzo(b)-fluoranthene (67.4), and among the other elements for Sb (73.1), Mo (59.6), Cr (33.9), As (24.1), Cu (19.6), and Zn (17.1). All these substances can thus be taken as indicators for road traffic pollution. Concentrations were also significantly higher in the tunnel mosses for all investigated substances than along busy roads outside tunnels. Cluster analysis revealed groups of substances which could sensibly be attributed to various sources (abrasion processes, Diesel combustion) and enrichment in the various particle size classes. DISCUSSION: The extreme high concentrations in the analysed moss samples from inside the tunnel were due to higher concentrations in the ambient tunnel air, and the fact that already deposited chemical substances are not lost by rain, as well as efficient uptake capacities even under the extremely adverse conditions in a tunnel. In accordance with previous studies our results suggest that PAHs are better indicators for emissions from the burning process than heavy metals. CONCLUSIONS: As in open fields, mosses are suitable indicators for monitoring traffic emissions in tunnels. In addition to biomonitoring in open fields, in tunnel experiments mosses are even better indicators, because the confounding effects of other sources of pollution and the 'noise' in the accumulation process (e.g. washout through wet deposition) are minimised. The results of our study demonstrate the usefulness of mosses for surveying heavy metals and PAH emissions and deposition arising from road traffic sources, even under the extremely adverse conditions of the tunnel environment. RECOMMENDATION: It can be considered that biomonitors like mosses are a suitable alternative to technical particle filters inside tunnels. They are easy to handle, low in costs and valuable information regarding traffic emissions can be obtained. PERSPECTIVE: The results of this pilot-study proved the feasibility of the method, however, should be corroborated by further investigations based on a sample set that allows for generalization of the findings and might even include other moss species. A comparison of technical measurements with the biomonitoring method could lead to a more general acceptance of the results.  相似文献   
27.
川西亚高山人工针叶林枯枝落叶及苔藓层的持水性能   总被引:38,自引:0,他引:38  
亚高山针叶林作为”长江上游生态屏障”的主体 ,具有重要的水源涵养和水土保持作用 .本文作者对川西地区典型的不同恢复阶段的人工云杉林、迹地、次生林和原始林下苔藓与枯枝落叶层贮量和持水性能进行了试验研究 .结果表明 ,人工云杉林在生态恢复过程中 ,苔藓与枯枝落叶层的贮量和持水性能均呈现出波动式递增 ,表现为 30a <4 0a <6 0a<5 0a,5 0a云杉林达到最大值 ,苔藓、枯枝落叶层的贮量分别为 10 .96× 10 3 kg/hm2 、76 .9× 10 3 kg /hm2 ,最大持水量分别为 4 4 .77× 10 3 kg /hm2 、182 .5× 10 3 kg /hm2 ,以后略有下降 .枯枝落叶层持水性能优于苔藓 ,说明枯枝落叶层在森林的水源涵养方面发挥了更为重要的作用 .人工林枯枝落叶层贮量和持水性能较天然林有所降低 ,反映了该地区在人工林的建设中应注意其生态功能的恢复 .图 2表 2参 8  相似文献   
28.
苔藓是生态系统的重要组分和自然保护区的重点保护对象之一,在物种资源和生态系统功能维护中具有重要作用.通过野外标本采集和室内鉴定,对九寨沟国家级自然保护区的藓类植物的物种组成和分布特点进行研究.结果表明:(1)九寨沟共有藓类植物38科90属211种(含变种),其中优势科为青藓科(Brachytheciaceae)、丛藓科(Pottiaceae)、灰藓科(Hypnaceae)、金灰藓科(Pylaisiaceae)、提灯藓科(Mniaceae)、真藓科(Bryaceae)和羽藓科(Thuidiaceae);并且调查发现两种濒危级别的珍稀藓种.(2)九寨沟藓类植物的区系地理成分可划分为10个,优势成分为东亚分布,占34.2%,其次为北温带分布,占30.9%.(3)通过与西南地区5个自然保护区藓类植物的相似系数和区系谱主成分分析发现,九寨沟藓类植物种类与贡嘎山的共有种最多,达到94种,在区系成分上也与贡嘎山和王朗相近.本研究表明九寨沟高原喀斯特生境藓类植物物种资源丰富,虽然区系地理成分具有多样和复杂性,但主要还是以东亚分布和温带分布为主,在物种相似度和区系成分上与贡嘎山和王朗的藓类植物一致性更高.(图3表6参47)  相似文献   
29.
Abstract: Our knowledge of cryptogam taxonomy and species distributions is currently too poor to directly plan for their conservation. We used inventory data from four distinct vegetation types, near Hobart Tasmania, to address the proposition that vegetation type, vascular plant taxon composition, and environmental variables can act as surrogates for mosses and macrofungi in reservation planning. The four vegetation types proved distinct in their taxon composition for all macrofungi, mosses, and vascular plants. We tested the strength of the relationships between the composition of cryptogam taxonomic groups and vascular plant composition and between the environmental variables and canopy cover. Taxon composition of woody vascular plants and vascular plants was the best predictor of the taxon composition of mosses and macrofungi. Combinations of environmental variables and canopy cover were also strong predictors of the taxon composition of mosses and macrofungi. We used an optimization routine for vascular plant taxa and woody plant species and determined the representation of cryptogam taxa in these selections. We identified sites with approximately 10% and 30% of the greatest proportions of vascular plants and woody vascular plants and calculated representation of mosses and macrofungi at these sites. We compared the results of these site selections with random site selections and random selections stratified by vegetation type. Random selection of sites by vegetation type generally captured more cryptogams than site selection by vascular plants at the 10% level. Vascular plant and woody plant taxon composition, vegetation type, and environmental and structural characteristics, all showed promise as surrogates for capturing common cryptogams in reserve systems.  相似文献   
30.
本文探讨了离子色谱法分析海苔食品中的碘含量的分析方法,采用戴安IGC-1500型,RFC-30淋洗液发生器,直接电导检测(电位:0.15V),对海苔进行定性,定量分析。该方法相对标准偏差RSD<0.8%(n=8),碘的回收率在94.0%~106.7%之间。方法简便、快速。  相似文献   
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