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1.
Morpho-physiological and biochemical parameters were determined in Scorpion fish Scorpaena porcus L. from two bays in the area of Sevastopol, which experience a high anthropogenic load. The effect of natural and anthropogenic factors on the size, weight, and age composition, as well as on the sex ratio of the fish from both populations, was studied. The relationships between the concentrations of chlororganic substances in the water of the bays, their accumulation in the liver and gonads of the fish, the activity of antioxidant enzymes in the blood, and the fractional composition of serum proteins were determined. A possibility for the use of the Scorpion fish as a indicator species for the biomonitoring and assessment of the environmental conditions in the coastal waters of the Black Sea was considered.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 238–246.Original Russian Text Copyright © 2005 by Rudneva, Shevchenko, Zalevskaya, Zherko.  相似文献   

2.
Results of hydrochemical and microbiological studies of five largest water bodies belonging to the Gusino-Ubukunskaya group are presented. Present-day environmental state of the ecosystem subject to anthropogenic load is described. The possibility of using water quality parameters of the investigated lakes as indicators of the degree of contamination of waters flowing into the Baikal Lake is shown.Translated from Vodnye Resursy, Vol. 32, No. 1, 2005, pp. 79–84.Original Russian Text Copyright © 2005 by Khakhinov, Namsaraev, Ulzetueva, Barkhutova, Abidueva, Banzaraktsaeva.  相似文献   

3.
Data on the composition and content of plant pigments in water of the Cheboksary Reservoir collected in 1985–2005 are used to analyze the seasonal dynamics and spatial distribution of phytoplankton at different stages of reservoir life. A trophic burst could be distinctly seen in the reservoir in 1985, manifesting itself in exceedingly high (198 ± 41 μg/l) concentrations of photosynthetic pigment chlorophyll. In the process of ecosystem stabilization, chlorophyll concentration significantly dropped to vary from 8.2 ± 1.5 to 45.1 ± 21.0 μg/l in 1989–2005. The reservoir, located in a region subject to high anthropogenic load, has acquired the features of an eutrophic water body immediately after its creation and its trophic status remains unchanged all over its existence.  相似文献   

4.
The characteristics of spatial and temporal distribution of tropospheric NO2 column density concentration over China are presented, on the basis of measurements from the satellite instruments GOME and SCIAMACHY. From these observations, monthly averaged tropospheric NO2 variations are determined for the period of 1997 to 2006. The trend and seasonal cycle are also investigated. The possible source of tropospheric NO2 over megacity area is discussed in this paper. The results show a large growth of tropospheric NO2 over eastern China, especially above the industrial areas with a fast economical growth, such as, Yangtze Rive Delta region and Pearl River Delta region because of the prominent anthropogenic activity. There is a rapid increase of tropospheric NO2 over megacities in China. For instance, Shanghai had a linear significant increase in NO2 columns of ～20% per year (reference year 1997) in the period of 1997-2006, which is the rapidest increase among all the selected cities. The seasonal pattern of the NO2 concentration shows a difference between the east and west in China. In the eastern part of China, an expected winter maximum in seasonal cycle is found because of the prominent anthropogenic activity and meteorological conditions. In the western part this cycle shows a NO2 maximum in summer time, which is attributed to natural emissions, especially soil emissions and lightning. A quickly increasing vehicle population may contribute to the increase of tropospheric NO2 over megacities in China for the remarkable correlation for vehicle population with tropospheric NO2.  相似文献   

5.
The formation of the fresh groundwater natural resources of the platform territories is analyzed. It is shown that within the artesian areas of platforms, the formation of the fresh groundwater natural resources is governed by the following main factors: the climatic conditions of the territory; the geological-structural features of the basin, substantially different in its peripheral and central parts; the structure of the zone of intense water exchange; the type of the water-bearing rocks and the character of the spatial variability of their hydraulic parameters; the aeration zone composition; the specific features of interaction between the groundwater and the hydrographic network and micro-relief of the territory. It is emphasized that the formation of the fresh groundwater natural resources within the hydrogeological massifs is governed not only by the physical-geographical conditions, but by the geological-structural factors as well. The formation and distribution of groundwater resources are governed by numerous natural and anthropogenic factors [11]. The combination of these factors and the significance of each factor are not constant but considerably vary in space, depending on the physical-geographical, geological, and hydrogeological conditions.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 146–153.Original Russian Text Copyright © 2005 by Vsevolozhskii, Kochetkova.  相似文献   

6.
The spatial distribution of aliphatic and polycyclic aromatic hydrocarbons (PAHs) was investigated in sediments from the Cienfuegos bay. The highest anthropogenic hydrocarbon inputs were found near the city of Cienfuegos with an unresolved complex mixture (UCM) of aliphatic hydrocarbons and alkylated PAHs, indicative of petrogenic inputs. Parent PAHs, which are typical of high-temperature combustion processes, were evenly distributed in the whole basin and largely prevailing in the southern part of the Cienfuegos city. Biomarker fingerprints assign the sources of pollution to mixes of national and non-national crude oils. The overall levels of anthropogenic hydrocarbons are relatively high compared to relevant areas worldwide and reveal a moderate/high level of hydrocarbon pollution. The Cienfuegos bay sediments received over a period of 5 yr, 50 T/yr of petrogenic unresolved hydrocarbons (UCM) and 2 T/yr of PAHs, being deposited the 80% in the sediments of the north basin.  相似文献   

7.
Results of studying the concentration of total, dissolved, and suspended organic matter in the water of the Amur and its main tributaries (the rivers of Bureya, Songhua, etc.) in 2005–2006 are presented. A high concentration of organic matter of anthropogenic origin was recorded in the water of the Songhua River, which has a significant effect on the Amur water quality. The export of organic matter with the Amur River water into the Amur Liman was accessed.  相似文献   

8.
Liu X  Xu L  Sun L  Liu F  Wang Y  Yan H  Liu Y  Luo Y  Huang J 《Marine pollution bulletin》2011,62(10):2205-2212
We reconstructed the first long-term (∼400 years) records of black carbon (BC) deposition flux from three ornithogenic sediment profiles, which were collected from three remote, isolated islets of the Xisha archipelago, South China Sea. The significant correlations between black carbon, organic matter and excess 210Pb suggested that black carbon was mainly derived from atmospheric deposition, and further enriched by plant-derived organic matter in sediments. During the past 400 years, the BC flux remained relatively low before the onset of 20th century; it started to increase from approximately 1900 AD, and peaked around the 1970s. In the recent 30 years, the BC flux seemed to display decreasing trend, very likely due to the change of energy structure and development of pollution control techniques. In comparison with marginal sea regions that are greatly impacted by anthropogenic activities, these pristine Xisha islands were not significantly influenced by black carbon of anthropogenic origin.  相似文献   

9.
The active crater of Nakadake at Aso Volcano, southwestern Japan, has been occupied by a lake during its dormant periods. Multiple ash emissions were observed from the crater lake between July 2003 and August 2005. The largest events occurred on 10 July 2003 and 14 January 2004. On 10 July 2003, ash (41 tons) was dispersed throughout an area extending 14 km east-northeast of the vent, and on 14 January 2004 ash (32 tons) extended 8 km to the east-southeast. Thereafter, small ash emissions were frequent at the crater lake, in which the water level fell considerably from April to August 2005. During this period major ash emitting events, producing mostly white aggregated ash, occurred on June 10–12, June 21 (4.2 tons) and July 25 (1.2 tons). Ash emissions at the Nakadake crater in 2003–2005 were classified into three types: gentle release of white aggregated ash from fumaroles inside the crater lake (e.g. daytime of 14 April, 10–12 June and 25 July 2005); emission of black ash from an almost dried-up vent (21 June 2005); and short-time (ca. 20 s) small-explosion-triggered gas-and-ash emission through the crater lake (10 July 2003, 14 January 2004 and 14 April 20h41m 2005). All products from these ash emissions consisted of fine-grained (< 1 mm) glass shards, crystals and lithic fragments, and contained neither lapilli nor blocks. Although the glass shards show varying degrees of crystallization and alteration, clear glass shards, which appear fresh, are probably juvenile materials. These observations suggest that the 2003–2005 ash emissions from the crater lake of Nakadake Volcano are related to newly ascending magma.  相似文献   

10.
Summary The nighttime LF radio wave absorption in the lower ionosphere measured at two frequencies in central Europe over 1963–1985 is used to infer planetary wave activity and its long-term trend in the upper middle atmosphere (∼90–100 km). The observed positive trend is roughly consistent with results based on daytime absorption. Nighttime results are less pronounced and less statistically significant probably due to perturbing effects of geomagnetic activity. The observed trends, which are probably of anthropogenic origin, are together with the daytime results [3,4] the first evidence of long-term trends in planetary wave activity in the upper middle atmosphere.  相似文献   

11.
Low-flow is widely regarded as the primary flow conditions for the anthropogenic and aquatic communities in most rivers, particularly in such an arid and semi-arid area as the Yellow River. This study presents a method integrating Mann–Kendall trend test, wavelet transform analysis and spatial mapping techniques to identify the temporal and spatial patterns of low-flow changes in the Yellow River (1955–2005). The results indicate that: (1) no trend can be identified in the major low-flow conditions in the upper Yellow River, but downward trends can be found in the middle and lower Yellow River; (2) similar periodic patterns are detected in the 7-day minima (AM7Q) in the upper and middle Yellow River, while different patterns are found in the lower Yellow River; (3) the increasing coefficients of variance in the primary low-flow conditions suggest that the variability of the low-flow is increasing from the upper to lower stream; (4) climate change and uneven temporal-spatial patterns of precipitation, jointly with highly intensified water resource utilization, are recognized as the major factors that led to the decrease of low-flow in the lower Yellow River in recent decades. The current investigation should be helpful for regional water resources management in the Yellow River basin, which is characterized by serious water shortage.  相似文献   

12.
Coral reefs in Jakarta Bay have been subjected to scientific studies since the 1920s. Also from that time on biological collections were made. The reefs in the Jakarta Bay have been under long-term natural and anthropogenic stress. With the biological collections and historical documents the coral species richness in Jakarta Bay around 1920 was reconstructed. New data from this bay and the adjacent offshore Thousand Islands archipelago were obtained during a 2005 research expedition. A comparison of the coral assemblages between 1920 and 2005 reveals a clear decline in species numbers. The most prominent results include the near-shore disappearance of species belonging to the families Acroporidae, Milleporidae, and to a lesser extent Poritidae. The overall coral species composition of the reefs has changed considerably, which is partly reflected in a strong decline in coral species richness. About half the number of species recorded in 1920 was found again in 2005.  相似文献   

13.
《国际泥沙研究》2022,37(5):563-575
Lacustrine sediment preserves high-resolution biogeochemical records of past variations in watershed processes controlling lake sedimentation. The current study explores historical variations in autochthonous and allochthonous sediment supplies to a large tropical freshwater lake system (Upper Lake, Bhopal) protected under the international Ramsar Convention of 2002 against anthropogenic pressures. For this purpose, multi-proxy biogeochemical data are presented for organic matter (total organic carbon, total nitrogen, phosphorous, and loss on ignition [LOI] at 550 °C), carbonate (LOI at 950 °C), lithic sediment (aluminum, titanium, iron, calcium, magnesium, sodium, potassium, manganese, zirconium, niobium, hafnium, tantalum, thorium, uranium, and rare earth elements), and anthropogenic inputs (lead) measured in a 38 cm long sediment core retrieved from the lake. In addition to the lacustrine sediment core, the samples of catchment bedrock, surface soils, major stream sediment, and eolian dust collected from the lake periphery also are analyzed. The systematic biogeochemical excursions in the upper core section (top ～8 cm) indicate increased anthropogenic inputs, watershed denudation by agricultural activities, artificially reduced fluvial sediment supply, relatively increased dust inputs and lake eutrophication in the last few decades. The current study underscores the roles of anthropogenic land-use and wetland conservation practices in the rapid alteration of autochthonous and allochthonous sediment supplies to open aquatic ecosystems. Further, rising lake eutrophication levels despite a managed reduction in allochthonous sediment supplies seem challenging to control due to dissolved nutrient supply from urban sewage discharge and runoff from agricultural land in the watershed.  相似文献   

14.
This work tests the capability of a recently published topographic index, the Slope Local Length of Auto‐correlation (SLLAC), to portrait and delineate anthropogenic geomorphologies. The patterns of the anthropogenic pressure are defined considering the road network density and the Urban Complexity Index (UCI). First, the research investigates the changes in the SLLAC in two derived parameters (average SLLAC and the SLLAC surface peak curvature – Spc – per km2) connected to the increasing of the anthropogenic structures. Next, natural and anthropogenic landscapes are clustered and classified. The results show that there is a direct correlation between the road network density and the UCI, and the mean SLLAC per km2. However, the Spc is inversely correlated with the anthropogenic pressure (network density and urban complexity). This shows that the surface morphology (slope) of regions presenting anthropogenic structures tends to be well organized (low Spc) and, in general, self‐similar at a long distance (higher average SLLAC). The results of the clustering approach show that the procedure can correctly depict anthropogenic landscapes having a road network density greater than about 3 km/km2, also in areas covered by vegetation. This latter result is promising for the use of such a procedure in regions that cannot be seen directly from orthophotos or satellite images. The proposed method can actively capture the alteration produced by road networks on surface morphology identifying different signatures of urban development: exploration and densification networks that are responsible for increasing the local density of the network and expanding the network into new areas, respectively. The effects of this alteration on surface processes could be significant for future research, creating new questions about differences due to human or landscape forcing on Earth surface processes. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

15.
A comparative study of the dynamics of Heterotrophic bacteriocenoses was carried out in three springs in the territory of Krylatskie Kholmy reserve in Moscow. The effect of abiotic (including anthropogenic) factors was assessed. Overall, the abundance of heterotrophic bacteria in springs in Krylatskie Kholmy reserve is at the level common for spring water. However, despite the relative closeness of springs, the microbiological characteristics of the “Svyatoi istochnik” spring radically differed from those in the other two springs. In particular, the number of bacteria by inoculation in this spring was always lower. This suggests the higher quality of water in the “Svyatoi istochnik” spring in terms of microbiological characteristics, which is likely due to a lesser anthropogenic effect.  相似文献   

16.
Analysis of Long-Term Variations in the Volga Annual Runoff   总被引：2，自引：0，他引：2  
Ismaiylov  G. Kh.  Fedorov  V. M. 《Water Resources》2001,28(5):469-477
The stability of sample estimates of statistical parameters was analyzed for segments of the initial time series of annual runoff volumes of the Volga River at Volgograd for 1881/1882–1994/1995. The segments of series considered in this study differ in the extent of anthropogenic impact on the runoff and the type of atmospheric circulation and correspond to characteristic periods in the Caspian Sea level variations. The conclusion is made that there are statistically significant variations in the annual runoff of the Volga, caused by both natural–climatic and anthropogenic variations in the hydrological cycle.  相似文献   

17.
Previous works have shown that ground deformation and seismicity in the Cerro Prieto geothermal field (CPGF) are due to both tectonics and field exploitation. Here, we use information about current tectonics and data from precision leveling surveys, to model tectonic and anthropogenic subsidence. Our results show that tectonic subsidence constitutes only ∼4% of the measured subsidence. Anthropogenic subsidence was evaluated using a model of rectangular tensional cracks, based on the hydrological model of the field, together with the Coulomb 2.0 program. From the resulting values of the fissure parameters and from extraction and injection data, we calculate that the volume changes caused by closure of the geothermal and cold water reservoirs account for only ∼3% and ∼7%, respectively, of the volume change which should occur due to extraction. Since 18% of the extracted fluids are reinjected, external recharge must compensate for about 72% of the expected volume reduction. An analysis of the changes in Coulomb stress caused by exploitation of the geothermal field suggest that even though the anthropogenic stresses account for only a fraction of tectonic stresses, they are large enough to trigger seismicity.  相似文献   

18.
Organic compounds were evaluated in March 2010 at 22 stations in Barkley Sound, Vancouver Island Canada and at 66 locations in Puget Sound. Of 37 compounds, 15 were xenobiotics, 8 were determined to have an anthropogenic imprint over natural sources, and 13 were presumed to be of natural or mixed origin. The three most frequently detected compounds were salicyclic acid, vanillin and thymol. The three most abundant compounds were diethylhexyl phthalate (DEHP), ethyl vanillin and benzaldehyde (∼600 ng L−1 on average). Concentrations of xenobiotics were 10-100 times higher in Puget Sound relative to Barkley Sound. Three compound couplets are used to illustrate the influence of human activity on marine waters; vanillin and ethyl vanillin, salicylic acid and acetylsalicylic acid, and cinnamaldehyde and cinnamic acid. Ratios indicate that anthropogenic activities are the predominant source of these chemicals in Puget Sound.  相似文献   

19.
The discharge of organic and biogenic substances by Russian rivers into the Arctic and Pacific seas, their anthropogenic component, and the trends in variations in the runoff of some components in individual periods of 1981–2000 are estimated.  相似文献   

20.
Arsenic(As) in natural hydrological systems is known as a worldwide major environmental concern. A geochemical and sedimentological study was done to ascertain the origin and geographical distribution of As in surface water and fluvial sediment collected from the floodplains/basins of the River Indus and its four major tributaries that drain through the northern Pakistan. The hydrogeochemical compositions of all five rivers were similar with calcium(Ca2+) and bicarbonate(HCO3  相似文献   

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