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1.
The state of the immune system was studied in the women working at the OAO Uralkalii (Berezniki) and OAO Sil'vinit (Solikamsk), where they were permanently exposed to salts and halite waste, and their children born after at least three years of such exposure. The control group consisted of women who had no occupational contact with salts and halite wastes and of their children. No significant differences between the differential leukocyte counts and immunograms of the women working at the OAO Uralkalii and OAO Sil'vinit and their children were found. The main parameters of the immune system of women and their children both in the first and second groups were within the norm.  相似文献   

2.
Ramsar, a northern coastal city of Iran, overlooking the Caspian Sea, has some high level natural radiation areas (HLNRAs) as well as over 50 hot springs with low and high radium contents used as spas by the public and vacationers. The average whole body dose received by population in these areas is about 5 times higher than the normal background radiation level. Studies on the long-term effects of high level natural radioactivity on some immunological and cytogenetical parameters, in the Ramsar inhabitants are summarized in this paper. Our results showed a significant increase of CD69 expression on TCD4+ stimulated cells (P < 0.004) and a significant increase of total serum IgE (P < 0.05), and also higher incidence of stable and unstable chromosomal aberrations in the HLNRA group compared to the control group with normal background radiation (P < 0.05).Other humoral immune parameters, did not show significant differences between the two groups.  相似文献   

3.
Hematological parameters of green frogs from populations exposed to the influence of urbanization and pollution were studied from 1999 to 2004. Manifestations of an adaptive response to a complex of corresponding ecological factors were observed, including the development of immune response and the enhancement of the protective function of peripheral blood. A negative correlation was revealed between the integrated index of the immune status and the number of T cells in the peripheral blood. This is evidence that parameters of the T-cell subpopulation are most informative and, therefore, have special significance for assessing the balance of immune system components.  相似文献   

4.
通过降低巢湖上覆水pH值以模拟限定条件的酸雨,旨在探究模拟酸雨对巢湖底泥营养盐和重金属释放的影响,以期预测酸雨或者酸性废水对湖泊生态系统稳定性的影响。结果表明:模拟酸雨过后上覆水的pH值均有回升,但强酸性模拟酸雨(pH 4.0)的恢复力较差;试验期间水体中的DO大小顺序始终为对照组试验组(pH 5.5)试验组(pH 4.0);模拟酸雨促进了底泥中氮和磷的的释放,且试验组(pH 4.0)上覆水中TN和TP含量显著高于试验组(pH 5.5)(p0.05);弱酸性模拟酸雨条件下以Fe/Al-P释放为主,强酸性模拟酸雨作用下以Ca-P释放为主;对照组的微囊藻生物量显著高于模拟酸雨组,说明模拟酸雨抑制微囊藻生长;pH值、TN、TP和Fe/Al-P均与底泥中四种主要重金属Pb、Zn、Cd和Cu含量显著相关(P0.05),说明酸雨和营养盐均是影响底泥中重金属赋存形态和释放性的重要因子。  相似文献   

5.
The effect of rearing conditions for gypsy moth larvae on parameters of their development (its duration and mortality) was studied in experiments with early instar larvae reared singly or in groups. The manifestation of the group effect was analyzed depending on the choice of experimental unit (the larva or the rearing container) and the amount of volume per larva. The observed effects were evaluated quantitatively.  相似文献   

6.
BACKGROUND: Against increasing environmental adverse effects on human health such as those associated with water and ground pollution, as well as out- and indoor air conditions, trials were conducted to support and promote human health by improving the indoor air atmosphere. This study was performed to estimate the effect of negatively-charged air conditions on human biological markers related to the psycho-neuro-endocrino-immune (PNEI) network. OBJECTIVES: After construction of negatively-charged experimental rooms (NCRs), healthy volunteers were admitted to these rooms and control rooms (CTRs) and various biological responses were analyzed. METHODS: NCRs were constructed using a fine charcoal coating and applying an electric voltage (72 V) between the backside of walls and the ground. Various biological markers were monitored that related to general conditions, autonomic nervous systems, stress markers, immunological parameters and blood flow. RESULTS: Regarding the indoor environment, only negatively-charged air resulted in the difference between the CTR and NCR groups. The well-controlled experimental model-room to examine the biological effects of negatively-charged air was therefore established. Among the various parameters, IL-2, IL-4, the mean RR interval of the heart rate, and blood viscosity differed significantly between the CTR and NCR groups. In addition, the following formula was used to detect NCR-biological responses: Biological Response Value (BRV)=0.498+0.0005 [salivary cortisol]+0.072 [IL-2]+0.003 [HRM-SD]-0.013 [blood viscosity]-0.009 [blood sugar]+0.017 [pulse rate]. CONCLUSIONS: Negatively-charged air conditions activated the immune system slightly, smoothened blood flow and stabilized the autonomic nervous system. Although this is the first report to analyze negatively-charged air conditions on human biological responses, the long-term effects should be analyzed for the general use of these artificial atmospheres.  相似文献   

7.
The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study area.The vegetation distribution was mapped in 1994 and 2007 based on TM remote sensing images by object-oriented interpretation method.We overlaid the two maps to find out the vegetation patches which have not changed,and took them as stable types.Fifty per cent of the stable patches were randomly sampled to operate the logistic regression with related environmental parameters;others were used as test data of simulated results.Seven environmental parameters were mapped,including elevation,slope,aspect,surface curvature,solar radiation,temperature and precipitation,based on DEM data and meteorological site data by GIS technology.The relationship between the spatial distribution of vegetation and environmental variables were quantified by logistic regression.The distribution probabilities of each vegetation type were calculated.Finally,the spatial distribution of potential vegetation was simulated.This research can provide a scientific basis for vegetation restoration and ecological construction in this area.  相似文献   

8.
The distribution of chemical elements in plants was studied in natural and technogenic ecosystems of the southern Baikal region. Basic statistical parameters characterizing the contents of a wide range of elements in different soil horizons and plants of the region and the “world land” (average for all the continents) were compared. On the basis of data on the distribution of chemical elements in the soil-plant system, groups of elements differing in the coeffient of biological absorption (C b) were distinguished. Evidence of antagonism between the main biophilous elements and heavy metals accumulating in plants was obtained. Interrelations of K and Na, which play an important role in the regulation of osmotic processes in plants, were analyzed. The phenomenon of potassium replacement by sodium in plants of technogenic ecosystems may serve as a criterion for assessing the phytotoxicity and environmental quality.  相似文献   

9.
The effect of complexing anion and adsorbate-adsorbent contact mode (static equilibrium or dynamic non-equilibrium) on binding and partition of Cu(2+), Cd(2+) and Zn(2+) onto organic matter (exemplified in a low-moor peat) was studied. The study comprised comparative batch and column flow-through sorption experiments on monometallic solutions of Me-Cl and Me-SO(4) salts, at pH 4.0, and sequential fractionation of sorbed metals with respect to binding strength. Both the presence of an anion having complexing properties (Cl(-)) as well as a contact mode was found to quantitatively and qualitatively affect the sorption capacity and binding strength of organic matter (peat) for metal ions. Complexing effect of Cl(-) on metal ions resulted mostly in reduction of metal ability to form strongly bound metal-organic compounds, in accordance with the order of stability constant of complex ions log K: Cd>Zn>Cu. Flow-through (dynamic) contact mode, which is the most appropriate to simulate environmental conditions, appeared to strongly attenuate the complexing effect of chloride ions on Cd and Zn sorption, and significantly enhance sorption capacity also in the absence of complexing ions. For Cd, it was mainly due to the enrichment in the strongly bound "insoluble organic" fraction, while for Zn the quantitative increase of sorption capacity did not alter significantly its partitioning. Neither a quantitative nor qualitative effect of contact mode on Cu binding was observed. Complex and diverse effects of different environmental parameters on metal sorption capacity and binding strength onto organic matter, which strongly influence metal mobility, leads to the conclusion that the correct simulation of these parameters for ecotoxicological testing is crucial for the reliable predicting of metal bioavailability under actual terrestrial environmental conditions.  相似文献   

10.
Young (1 month old) and mature (2 years old) constructozems (artificial soils) were supplemented with individual heavy metal salts or diesel fuel at different concentrations. The polluted and control constructozem variants were incubated and sampled at different time points to determine microbial biomass carbon (Cmic) and microbial respiration (MR). These parameters were found to be almost twice higher in the young than in the mature constructozem, with all pollutants causing an increase in Cmic, MR, and MR/Cmic = qCO2 values. The pollutant type had an effect on MR and qCO2 variances, and the time of exposure, on Cmic. The qCO2 value showed a strong positive correlation with pollutant concentrations, allowing this parameter to be regarded as a suitable indicator of urban environmental pollution.  相似文献   

11.
以长江下游典型平原河网地区苏州市为例,基于1970s、1990s、2010s的遥感影像以及1960s、1980s、2010s水系数据,构建水系结构参数指标,重点探讨不同城市扩张方式对不同等级水系的干扰程度,以揭示城市空间扩展与水系结构演变的关系。结果表明:(1)城市扩展具有阶段性、趋向性,且受到自然环境和社会经济的影响与制约。(2)河网水系的改造和演化在不同城市化进程下表现出区域差异:近年来快速城市化区域的河网密度、水面率等水系结构指标变幅较大;80年代城市化区域变幅次之;进入高度城市化阶段的老城区,变化最小且稍有增加,其中近50年来河网密度在上述3个区域总体变幅为-21.06%、-16.23%以及1.88%。(3)河流结构发育受城市化进程显著影响,自然状态下河流长度与面积之比较大,河流结构更为稳定,而进入城市化阶段后,河流结构稳定性随之降低。该研究为城市化地区河流水系保护、城市规划及防洪减灾提供参考与理论支撑。  相似文献   

12.
Mechanisms of changes in the numbers of red deer in the Caucasian State Biosphere Reserve (the northwestern Caucasus) were studied from 1958 to 2004 using simulation models developed on the basis of concepts concerning the combined effect of density-dependent and density-independent factors. The results show that changes in population numbers are accounted for by larger (more numerous) local subunits, with small groups remaining relatively stable. In the periods of depression, such a mechanism provides for the maintenance of the spatial population structure.  相似文献   

13.
目前国内外关于排污权交易方面的研究很多,但是大多数学者在排污权交易的理论研究和实践讨论中忽略了排污权交易对产品市场结构的影响问题.实际上,在中国市场体制并不完善的条件下实施排污权交易制度,有可能导致排污权交易市场以及产品市场的扭曲,必须对此加以研究.文章建立了排污权交易条件下的古诺离散动态系统模型,分析了排污权交易条件下古诺市场动态均衡及其稳定性问题.理论研究和数值模拟的结果表明:当排污权交易价格、厂商调整产量的相对速度、边际污染治理成本以及边际生产成本等参数发生变化时,纳什均衡点失去稳定性,经倍周期分叉后出现混沌状态.厂商调整产量的相对速度越慢,厂商的利润越稳定;厂商的边际生产成本、边际污染治理成本、污染排放系数以及排污权交易价格等参数越大,厂商要承受的风险也就越大,厂商对产量的调整余地也越小,厂商的利润相对稳定.  相似文献   

14.
Cytogenetic variation was analyzed in daughter populations of Scotch pine from the Voronezh Forestry. The dependence of the variation on the method of seed collection (the commercial method; the population method, when seeds from a group of phenotypically normal trees in the center of the forest are collected; or the individual method, when seeds from plus trees are collected) and on the ecological situation at the sampling site (ecologically safe conditions or chemical or physical pollution) was studied. The parameters of the mitotic rate and mitotic pathology were estimated at 7–9% and up to 5%, respectively. These parameters may be considered as normal when estimating the quality of seed progeny in pine and when pine is used as a test object in cytogenetic monitoring. The limits of variation and the spectra of cytogenetic characteristics allowing the pine populations to maintain their homeostasis were also determined.  相似文献   

15.
采用野外调查和取样分析相结合的方法,对武汉市郊部分设施蔬菜栽培地土壤盐分特征进行了研究。结果表明:(1)在研究区,轻度盐化土壤占5263%,中度盐化土壤占2105%,重度盐化土壤占526%,另有1579%的设施土壤盐分含量超过了10 g/kg,达到盐土〖JP+1〗的标准。(2)设施栽培土壤的可溶性盐含量与电导率(EC)均明显高于露天栽培菜地及植棉地土壤,且变化幅度大,平均值分别为66 g/kg〖JP〗和031 mS/cm。其中,10.5%的设施土壤表层EC值达到了作物生长障碍临界点(>06 mS/cm)。表层土壤中以NO-3和Ca2+的相对富集为主要特征。(3)盐分的运移同时存在着向下迁移和向表层聚集两种方式,且以表聚为主。除HCO-3外,其它盐分离子的含量随土层深度的增加而有所降低,其中,NO-3、Ca2+累积迁移量较大,在0~100 cm各土层内的含量都高于露天菜地和植棉地,硝酸盐的大量累积和向下迁移势必对地下水造成不利影响。(4)设施地栽培的土壤水溶性盐含量与电导率(〖WTBX〗r=0.951 2*〖KG-*3〗*)以及硝态氮含量(r=0.644 2*)分别呈极显著和显著正相关。〖  相似文献   

16.
Foliar damage to aspen from leaf-chewing insects and miners has been assessed during a 4-year period in the environs of a large copper smelter in the Middle Urals. It has been shown that the total area removed, proportion of damaged leaves, and average area removed per damaged leaf are considerably smaller near the smelter than in the background zone. The degree of the effect is similar for all three parameters and remains stable with time. Both groups of leaf pests display lower trophic activity in the impact zone, but the effect of pollution on leaf-chewing insects is greater than on miners, while individual features of the tree and its environment affect miners more strongly than leaf-chewing insects.  相似文献   

17.
流域水资源丰富度评价的MFP模型及应用   总被引:1,自引:0,他引:1  
水资源系统与许多因素有关,如各种水资源量、人口、社会经济发展指标等,它们共同组成了一个典型的复杂非线性系统。以最大流原理为基础,导出了描述水资源系统的信息动力学演化方程,建立了水资源评价的信息动力学模型,运用信息动力学模型建立了评价标准。该模型无需人为给定参数,客观性强,操作简便。最后运用理论模型对辽西沿海诸河流域水资源丰富度进行评价分析,得到各流域的丰富度状况,并与其它模型评定结果做出了比较,结果表明该方法具有较好的合理性和可操作性。由于该模型从一定程度上体现了水资源丰富度系统的演化动力学机理和水资源系统时空演变特性。因此,不仅在评价上有较大的优越性,在水资源丰富度发展变化状态的预测上也具有潜力。  相似文献   

18.
Glycine uptake by an isolated Pseudomonas species as a sole nitrogen source was studied in the presence of inorganic particulate. A pure culture of Pseudomonas species was grown in a continuous culture apparatus using a nitrogen-limited medium. The biomass from the chemostat was used in batch studies to evaluate the effects of alumnia or kaolinite on the glycine uptake rate. Stimulation and inhibition were dependent on the surface area of the particles added to the system. Stimulation occurred at low particle concentrations, while inhibition occurred at higher particle concentrations. Enhanced glycine uptake is attributed to an “adsorption” mechanism which may associate with the removal of toxic inhibitors from solution by adsorption onto the particle surface. Inhibition by these particles at high surface area densities may involve the removal of required compounds, as a factor of the particle surface area and not its size or type.  相似文献   

19.
It is well known that the structure of leaves plays an important role in adaptation, but there are still no accurate structural criteria to indicate ecological characteristics of the species. We have studied parameters of leaves in 100 herbaceous plant species growing in the southern taiga subzone that belong to different ecological groups in relation to irradiance and moisture supply. The results show that leaf area, thickness, and anatomical type are less correlated with ecological characteristics of the species than structural parameters of photosynthetic tissues. In the series shade-loving mesophytes—light-loving hygromesophytes—mesophytes—xeromesophytes—mesoxerophytes, the concentration of cells and chloroplasts in the leaf gradually increases by a factor of up to 7–10, their size decreases two-to threefold, and the ratio of mesophyll surface area to leaf surface area increases fourto fivefold. It is concluded that characteristics of mesophyll are of adaptive significance. A system of characters is proposed for identification of ecological groups of plants growing in the boreal zone.  相似文献   

20.
Biosphere dose conversion factors are computed for the French high-level geological waste disposal concept and to illustrate the combined probabilistic and deterministic approach. Both 135Cs and 79Se are used as examples. Probabilistic analyses of the system considering all parameters, as well as physical and societal parameters independently, allow quantification of their mutual impact on overall uncertainty. As physical parameter uncertainties decreased, for example with the availability of further experimental and field data, the societal uncertainties, which are less easily constrained, particularly for the long term, become more and more significant. One also has to distinguish uncertainties impacting the low dose portion of a distribution from those impacting the high dose range, the latter having logically a greater impact in an assessment situation. The use of cumulative probability curves allows us to quantify probability variations as a function of the dose estimate, with the ratio of the probability variation (slope of the curve) indicative of uncertainties of different radionuclides. In the case of 135Cs with better constrained physical parameters, the uncertainty in human behaviour is more significant, even in the high dose range, where they increase the probability of higher doses. For both radionuclides, uncertainties impact more strongly in the intermediate than in the high dose range. In an assessment context, the focus will be on probabilities of higher dose values. The probabilistic approach can furthermore be used to construct critical groups based on a predefined probability level and to ensure that critical groups cover the expected range of uncertainty.  相似文献   

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