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1.
Ermolaeva  N. I. 《Water Resources》2020,47(1):113-121
Water Resources - The species diversity and the quantitative characteristics of zooplankton in the Vatinskii Egan River have been studied in its middle and lower reaches. The river suffers...  相似文献   

2.
Stream pollution by industrial wastes is posing a problem in Uttar Pradesh. In the present investigations an attempt has been made to study the ecological features of a section of the Kalinadi so as to find out the cumulative or detrimental effect of pollution on fish and fisheries by the effluent discharge of sugar factory and distillery wastes near Mansurpur (District Muzaffarnagar), U. P. This paper is part I of the project. The liquid wastes produced by the sugar factory vary from 66 × 106 to 88 × 106 litres/day excluding condenser water and contain variable quantities of cane fibres, cellulose, lime, waxes, fermented sugar juice, mollasses, and some quantities of sulphate, phosphate, and nitrogen, the oxygen being nil with high values of B. O. D. and C. O. D. The liquid waste from the distillery is called spent wash. The spent wash (62 × 104 litres/day) is highly coloured and acidic (pH 4.3 … 2.9). The B. O. D. and C. O. D. values were very high in the order of 28,526 mg/1 … 45,146 mg/1 and 52,516 mg/1 to 66,862 mg/1. Thus total waste of about 17.3 × 106 litres with no oxygen and high B. O. D. (9,600 mg/1 … 10,116 mg/1) is let off into the Kalinadi. Hydrometric observations on the Kalinadi show that the pollutional hazard is appreciable during the low flow period of the river. The wastes affect the river in a number of ways:
  • - The deposition of cellulose fibres, organic and inorganic matter affects the substratum adversely. The blackish brown colour of the wastes affects the light penetration by limiting the growth of phytoplankton.
  • - There appears to be no potential danger to the river from the electrolyte pollution as the specific conductivity lies below limiting values.
  • - Changes in pH in river water due to the acidic nature of the wastes do not affect directly the fauna and flora, but the acidic condition becomes lethal in the presence of low oxygen and high temperature values.
  • - The high load of organic matter present in the wastes draws heavily on the oxygen budget of the river and adversely changes the water and bottom quality of the river for a stretch of 10 km, which adversely affects the environmental condition of both fish and fish food.
  • - The presence of sulphuric acid in distillery waste and hydrogen sulphide in river water is toxic to fish and fish food.
  • - The decomposition of organic matter in an anaerobic condition and in another favourable environment, as with a low redox potential, the presence of sufficient organic matter and a constant supply of sulphur-reducing bacteria, produces more hydrogen sulphide which may be detrimental or sublethal in the presence of a low oxygen saturation and high temperature.
  • - The oxygen level increases at each succeeding station through reaeration and dilution with the lowering of B. O. D. and C. O. D. The oxygen-sag curve is like a typical spoon with handle-shape.
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3.
The aim of this research was to assess the impact caused by a long‐term pollution by fluoride and heavy metals in two soils (PS1 and PS2) near an aluminium smelter in Slovakia, on soil microbial biomass C (MBC), basal respiration, metabolic quotient (qCO2) water‐soluble organic C (WSOC) and enzymes activities involved in the C, N and P biogeochemical cycles. An unpolluted soil was used as control (C0). Results obtained for soil fluoride content reflected a gradient of fluoride exposure in topsoils of contaminated sites. Decreases in microbial and enzymatic activities and in MBC to organic C ratio were found in PS2 site, which is closer to the smelter and exhibited the highest fluoride content. PS1‐soil showed an extreme alkaline pH caused by leaching of waste effluents from the smelter dumping site, higher contents of Zn, Cu, Pb and Cd, significantly larger MBC, qCO2 and catalase and urease activities, and much larger basal respiration and dehydrogenase activity than PS2 and C0‐soil. Phosphatase, β‐glucosidase and BAA‐protease were negatively correlated with WSOC, basal respiration and dehydrogenase activity, and showed some degree of inhibition in polluted sites. These results may indicate different responses of microbial communities to ecosystem disturbances, caused by the drastic changes in soil's physicochemical properties as result of the long‐term emissions of fly ash with high levels of contaminants that are still affecting soil microbial and enzymatic activities.  相似文献   

4.
Zooplanktonic fauna of waste water from the industrial complex at Birla Nagar, Gwalior alongwith its seasonal abundance have been studied. In all, 16 species have been identified, viz. Arcella discoides, Lesquereusia modesta, Difflugia corona, D. muriformes and Acanthocystis spinibera under protozoa, Brachionus calyciflorus, Br. caudatus, Br. falcatus and Keratella tropica under rotifera, Daphnia (Daphnia) carinata and Daphnia (Daphnia) lumholtzi under cladocera, Cypris sp. and Cyprinotus qunninqi under ostracoda and Spicodiaptomus chelospinus and Mesocyclops leuckarti under copepoda. In their seasonal abundance members of protozoa showed the maxima in the month of April while the minima were observed in the month of July with an irregular trend of fluctuation. Rotifers, however, exhibited two maxima, one each during winter and early summer. Cladocera were maximum in February, while minimum in October. Ostracodes were maximum during May and June. Copepods were highest in the months of August and lowest in February. The total zooplankton population presented a clear-cut bimodal pattern of their seasonal fluctuation with the first peak appearing in the month of April and the other one in November. Lowest counts were obtained in the month of February. The zooplanktonic organisms belonging to rotifera were relatively abundant, followed by protozoa, copepoda, ostracoda and cladocera in a sequence.  相似文献   

5.
Zooplankton of the lake Jaisamand was represented by 50 taxa out of which 22 were Rotifera, 18 Cladocera, 5 Protozoa, 3 Copepoda and 2 Ostracoda. The total zooplankton exhibited a bimodal pattern with the first peak occurring in December and the second of a little less magnitude in June. The perennial zooplankters were Keratella valga, Brachionus falcatus from Rotifera, Ceriodaphnia spec. from Cladocera and Mesocyclops and Heterocyclops spp. from Copepoda. Considering surface zooplankton as a whole, Rotifera dominated the planktonic biomass followed by Copepoda, Cladocera, Ostracoda, Protozoa and Insecta. The species composition of the mid-stratum zooplankton was not much different from that of the surface. Interestingly, there was a presence of Cladocera in the anoxic bottom waters. The low and occasional presence of Calanoid copepods, the abundance of Cyclopoids and Cladocerans point to the eutrophication in the lake.  相似文献   

6.
不同污染程度湖泊底栖动物群落结构及多样性比较   总被引:34,自引:5,他引:34  
首次对湖北梁子湖水系污染程度不同(中营养型、中富营养型、富营养型)的4个湖泊的底栖动物群落结构和物种多样性进行了周年研究,结果表明,底栖动物种类数、物种多样性与湖泊受污染程度呈负相关系,密度与污染程度大体上呈正相关.还讨论了底栖动物环境指示种生态特性,研究表明中国长足摇蚊的密度与水体营养水平呈正相关,软体动物种类数与湖泊污染程度呈负相关.通过对软体动物、寡毛类及摇蚊类密度和生物量在不同湖泊之间的差异的分析,表明湖泊水体污染导致了底栖动物多样性明显降低.  相似文献   

7.
The effect of anthropogenic pollution on the structure of benthic animal communities in the Barnaulka R. (Ob tributary) has been studied. Statistical analysis was used to assess the effect of habitat factors on macrozoobenthos structure. The structure characteristics of benthic macroinvertebrate communities and the bioindication indices calculated from them are shown to depend on the hydrophysical and hydrochemical characteristics of water and bottom sediments.  相似文献   

8.
From the biological data presented here it is difficult to define any species of fish as an indicator of pollution in the strict sense. Nevertheless, the following generalizations are possible.
  • - Species as Wallago attu, Clarias batrachus, Heteropneustes fossilis, Ophiocephalus striatus and Oph. punctatus occur in good number in the polluted stretch and seem to be tolerant species.
  • - The species as Esomus danrica, Labeo rohita, Labeo gonius, L. bata, Catla catla, Cirrhina mrigala, Barbus chagunio, Barbus spec., Notopterus notopterus and Mugil corsula are most sensitive and disappear first in the polluted stretch.
  • - The species as Barilius bola, B. bendelisis, Nemacheilus latius, Notopterus chitala, Collichrous bimaculatus, and Nandus nandus are moderately sensitive.
  • - It appears that the main damage is caused to carp and feather-back fishes. The whole stretch of heavy pollution is almost devoid of carp and featherback.
The following important conclusions can be drawn from the distribution of plankton and bottom organisms:
  • - The higher number of protozoans, chironomids, maggots and the decrease in the number of mollusca can be considered as the indicator of pollution, because of their abundance in polluted zones.
  • - Chlorella, Lyngbya, Gyrosigma and Euglena (algae), Viviparius (mollusc) and Bosmina (crustacea) are very sensitive to pollution.
  • - Oscillatoria, Pandorina, Anabaena, Nitzschia, Closterium (algae), Branchionus, Rotatoria (rotifers) and Naidium (annelid) are moderately sensitive.
  • - Synedra, Spirogyra, Desmidium, Rivularia, Navicula, Fragillaria Phacus, Arcella and Vorticella are fairly tolerant forms.
  • The stretch studied has been subdivided into five zones with characteristic features:
  • - The Oligosaprobic Zone - characterized by a sufficient oxygen saturation, low B. O. D. and C. O. D., with a good fauna and flora.
  • - The Polysaprobic Zone - with low oxygen saturation, high B. O. D. and C. O. D. and hydrogen sulphides with a restricted fauna and flora.
  • - The α-Mesosaprobic zone - with moderate oxygen saturation, moderate B. O. D. and C. O. D. traces of hydrogen sulphide with the improvement of the fauna and flora.
  • - The β-Mesosaprobic Zone - with fair oxygen saturation, low B. O. D. and C. O. D., with the reappearence of fauna and flora.
  • - The Oligosaprobic Zone - similar to the zone of low pollution in all characteristics.
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9.
10.
Water Resources - The formation and distribution of river flow characteristics in the Don basin have been catholically analyzed, depending on the present-day climatic conditions in the central...  相似文献   

11.
为了探明百花湖麦西河后生浮游动物的群落组成及动态特征,于2009年8月至2011年8月对百花湖麦西河河口后生浮游动物进行调查研究.结果表明:百花湖麦西河河口共监测到轮虫29种,丰度为0.16~837.80 ind./L;桡足类浮游动物仅检测到了温中剑水蚤(Mesocyclops thermocyclopoides)和猛水蚤(Harpacticella sp.)2种,以无节幼体和桡足幼体为主,其丰度为0~642.75 ind./L;枝角类浮游动物9种,丰度为0~31.20 ind./L.后生浮游动物的丰度主要由轮虫和桡足类组成,轮虫丰度比例为4.09%~100%,桡足类丰度比例为0~95.64%.前节晶囊轮虫(Asplanchna priodonta)、卜氏晶囊轮虫(Asplanchna brightwelli)、裂足臂尾轮虫(Brachionus diversicornis)为轮虫类的主要优势种,最高丰度分别达到424.88、392.20和61.99 ind./L;长额象鼻溞(Bosmina longirostris)为枝角类优势种,最高丰度达到27.93 ind./L.轮虫丰度与透明度、总氮、硝态氮呈极显著正相关;枝角类丰度与透明度、硝态氮呈极显著正相关,与温度呈极显著负相关.  相似文献   

12.
—?During 1997 and 1998, twelve chemical explosions were detonated in boreholes at the former Soviet nuclear test site near the Shagan River (STS) in Kazakhstan. The depths of these explosions ranged from 2.5 to 550 m, while the explosive yield varied from 2 to 25 tons. The purpose of these explosions was for closure of the unused boreholes at STS, and each explosion was recorded at local distances by a network of seismometers operated by Los Alamos National Laboratory and the Institute of Geophysics for the National Nuclear Center (NNC). Short-period, fundamental-mode Rayleigh waves (Rg) were generated by these explosions and recorded at the local stations, resultingly the waves exhibited normal dispersion between 0.2 and 3 seconds. Dispersion curves were generated for each propagation path using the Multiple Filter Analysis and Phase Match Filtering techniques. Tomographic maps of Rg group velocity were constructed and show a zone of relatively high velocities for the southwestern (SW) region of the test site and slow propagation for the northeastern (NE) region. For 0.5?sec Rg, the regions are separated by the 2.1?km/sec contour, as propagation in the SW is greater than 2.1?km/sec and less in the NE region. At 1.0 sec period, the 2.3?km/sec contour separates the two regions. Finally, for 1.5 and 2.0 sec, the separation between the two regions is less distinct as velocities in the NE section begin to approach the SW except for a low velocity region (<2.1?km/sec) near the center of the test site. Local geologic structure may explain the different regions as the SW region is composed predominantly of crystalline intrusive rocks, while the NE region consists of alluvium, tuff deposits, and Paleozoic sedimentary rocks. Low velocities are also observed along the Shagan River as it passes through the SW region of the test site for shorter period Rg (0.5–1.0?sec). Iterative, least-squares inversions of the Rg group velocity dispersion curves show shear-wave velocities for the southwestern section that are on average 0.4?km/sec higher than the NE region. At depths greater than 1.5?km the statistical difference between the models is no longer significant. The observed group velocities and different velocity structures correlate with P-wave complexity and with spatial patterns of magnitude residuals observed from nuclear explosions at STS, and may help to evaluate the mechanisms behind those observations.  相似文献   

13.
于2008-2009年按照季节调查西藏地区尼洋河浮游动物群落的组成、丰度和多样性,并运用多元统计方法定量分析浮游动物的空间和季节变化特征及其与主要环境因子之间的关系.结果显示,尼洋河浮游动物包括原生动物、轮虫、枝角类和桡足类,其中原生动物9目13科14属,轮虫1目7科17属,枝角类仅1目1科1属,桡足类2目2科2属.原生动物以砂壳虫和瞬目虫属为主,轮虫则以橘轮虫属和单趾轮虫属为主.尼洋河浮游动物的物种丰富度和生物量随尼洋河海拔高度不断提升呈现递减的趋势,夏季浮游动物生物量、物种丰富度、总丰度较低,其中夏季浮游动物物种丰富度最低,而浮游动物生物量和总丰度则仅高于冬季.受到水体稳定性的影响,尼洋河浮游动物Shannon-Wiener多样性指数和均匀度指数在交汇处较低;季节方面,夏季最低,冬季次之.尼洋河原生动物和轮虫总丰度在季节方面存在相似的演替规律,即出现2次高峰和2次低谷,2次高峰分别出现在春季和秋季,2次低谷分别出现在夏季和冬季.尼洋河浮游动物沿程变化方面,浮游动物群落4个指标不存在显著差异.尼洋河浮游动物季节变化方面,仅总丰度秋季和冬季之间存在显著差异,其他3个指标在各个季节之间均不存在显著差异.典范对应分析表明,原生动物类群里,砂壳虫属丰度受水体溶解氧浓度的影响较大,前管虫、袋座虫、肾形虫、瞬目虫和斜口虫属丰度受水体矿化度的影响较大,鳞壳虫属丰度则主要与水体中氨氮浓度关联较大;轮虫类群里,单趾轮虫、无柄轮虫、枝胃轮虫、囊足轮虫属丰度与水体的矿化度关联较大,龟甲轮虫属丰度则与总磷浓度有着较大的关联.分类回归树模型预测了尼洋河浮游动物时空分布与主要环境因子之间的定量关系,结果表明尼洋河浮游动物总丰度受到硬度、季节、海拔以及河道底质等因素的影响,Shannon-Wiener多样性指数受到总碱度、季节、硬度和水温的影响,均匀度指数受到总碱度、总磷浓度和水温的影响.这些关键环境因子对尼洋河水域浮游动物的时空变化有着重要的指示作用,建议加强对浮游动物及这些环境因子的关注,推动尼洋河水域生态环境的可持续发展.  相似文献   

14.
In the past 30 to 40 years, floodplain areas of large rivers, such as the Missouri River, have been extensively used for large industrial and municipal landfills. Many of these sites are now causing varying degrees of ground water contamination. Rapid geophysical characterization techniques have proven useful for delineation of anomalous areas indicative of potential contaminant plumes. These methods have also resulted in a cost effective approach to the location and number of monitoring wells.
An effective technique to initially characterize ground water contamination at such landfills along the Missouri River in northwestern Missouri involved a combination of electrical resistivity and electromagnetic conductivity methods. Resistivity was used to obtain soundings of the alluvium by using a modified Wenner array and to corroborate shallow electromagnetic conductivity measurements by using short Wenner array electrode spacings.
Upon confirmation of similar measurements of the upper soils for the two methods, numerous electromagnetic conductivity traverses were made at each landfill site. The data generated from these surveys were graphed and contoured to delineate anomalous areas. Based on the geophysical study, a ground water monitoring well network was then designed for each landfill.
As a result, a minimal number of wells were required to initially characterize the ground water quality at these two sites. In general, analysis of water samples from these wells displayed good correlation with the geophysical results.  相似文献   

15.
Krupa  E. G.  Barinova  S. S.  Romanova  S. M. 《Water Resources》2019,46(3):403-414
Water Resources - The size structure of zooplankton in Kolsay Lakes was characterized with the use of the values of Clarke W-statistic, ?-Shannon–Weaver, and the average individual mass...  相似文献   

16.
2009年7月至2010年6月,以每月一次的频率对百花湖(水库)麦西河河口浮游植物群落结构和环境因子进行调查.监测到浮游植物66种(属),浮游植物主要由绿藻、硅藻和蓝藻组成,夏秋季湖泊假鱼腥藻(Pseudanabaena limnetica)为优势浮游植物,而冬春季梅尼小环藻(Cyclotella meneghinia...  相似文献   

17.
We applied the 3D first arrival travel time tomography method to the Anhui active seismic source experiment data,and obtained the imaging of the upper crust velocity structure beneath the Yangtze River from Ma'anshan,Tongling to Anqing. Data fitting reveals the tomographic model fits the data with uncertainties, without overfitting, and with a minimum of complexity. The tomographic result shows an obvious heterogeneous upper crust which consists of a series of uplifts and depression basins. The velocity model and region imply that this region has experienced crustal uplift and extensional tectonism with concomitant magmatism since the Cenozoic.  相似文献   

18.
Ermolaeva  N. I. 《Water Resources》2022,49(1):109-121
Water Resources - It is shown that the presence of petroleum hydrocarbons in water may have both a depressing and a stimulating effect on the development of certain species of zooplankton. The...  相似文献   

19.
陈越  潘保柱  吴利  胡恩  赵耿楠  张森 《湖泊科学》2022,34(5):1630-1641
浮游动物作为食物链中重要的初级消费者,其群落结构特征是水生态系统健康评价的重要指标之一.本研究于2017年秋季和2018年春季对渭河干流及秦岭北麓五条典型支流开展了系统的水环境及浮游动物群落调查.结果表明,渭河干流营养盐浓度整体高于秦岭北麓支流,干流浊度远高于支流.两次调查共鉴定出浮游动物种类数136种(原生动物65种,轮虫44种,枝角类15种,桡足类12种),其中2017年秋季渭河干流浮游动物种类数、密度和生物量分别为14种、9.02 ind./L和0.0051 mg/L,秦岭北麓支流为37种、42.78 ind./L和0.0229 mg/L;2018年春季渭河干流浮游动物种类数、密度和生物量分别为52种、292.89 ind./L和0.1734 mg/L,秦岭北麓支流为68种、70.15 ind./L和0.0508 mg/L.秋季渭河干流下游浮游动物种类数、密度和生物量最低,而春季随上、中、下游三者均依次增大;秋季秦岭支流中罗敷河浮游动物密度和生物量最高,而春季灞河最高.春、秋两季干支流间浮游动物优势种差异较小,但秋季优势种种类数少于春季.秋季渭河干流中游Shannon-Wiene...  相似文献   

20.
近场震级起算函数确定与爆炸余震震级计算   总被引:1,自引:2,他引:1  
李学政  王海军  雷军 《中国地震》2003,19(2):117-124
在天然地震背景下,由于现有的起算函数在0—5km范围内是一个常数,因此,对于震源深度较浅的小地震震级的测定遇到了困难,本文通过理论计算和爆炸地震波实际测量两种方法,确定了近场0—5k瑚范围内的震级起算函数。用本文确定的震级起算函数计算了两次爆炸余震序列事件的震级,绝大多数的余震震级非常小,主要分布在-0.5—1.0级之间,余震序列的M-t图与一般强余震M-t图明显不同,它不仅存在反映较大震级的正向柱状线,而且还存在反映较小震级的负向短柱状线。  相似文献   

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