Acute and Chronic Toxic Effects of Cadmium on some Haematological,Biochemical, and Enzymological Parameters in the Fresh Water Teleost Fish Channa punctatus Akute und chronisch toxische Wirkungen von Cadmium auf einige hämatologische,biochemische und enzymologische Parameter im Süßwasserfisch Channa punctatus

The haematological, biochemical, and enzymological alterations produced on exposure of Channa punctatus to LC₅₀ (11.2 mg/L) for 96 h and to a sublethal concentration (1.12 mg/L) of cadmium (Cd²⁺) for 15, 30, 60, and 120 days have been studied. The fish were hypoglycemic and hypolactemic. The pyruvate content of blood and liver decreased in acute and all stages of chronic exposure except for 30 days where significant increase was recorded. Depletion was noted in the total protein and glycogen content of liver and muscle, and the level of lactate in liver in the two types of exposure. The levels of muscle lactate and pyruvate increased in both exposures. The activities of hexokinase, glucose-6-phosphatase, and lactate dehydrogenase decreased in liver after 96 h and all stages of chronic exposure except 30 days. The activities of hexokinase and lactate dehydrogenase in muscle and glutamate-oxalacetate transaminase and glutamate-pyruvate transaminase in serum, liver, and muscles increased in all exposures. The activities of succinate and malate dehydrogenases in liver and muscles decreased after acute and all stages of chronic exposure. The above results suggest that glycolysis and gluconeogenesis were impaired in liver but glycolysis prevailed in muscle. Aerobic oxidation is adversely affected in metal exposed fish, while proteolysis was increased.     

Deleterious effects of Malathion on survivality and growth of the fingerlings of Channa punctatus (BLOCH.), a freshwater murrel

The LC₅₀ of Malathion for Channu punctatus is determined for 24… 96 h of exposure as 10.95… 3.22 mg/l. At exposure to 2.5 mg./l Malathion, growth–measured by increase in weight–is significantly reduced from the 19th day and reduced by 10 % till the 31st day. During the same period of time, the RNA and protein contents of the muscle is lowered by 10 and 15 %, respectively, as compared with the control. In addition to an acute toxic effect, in sublethal concentrations Malathion has also pronounced effects on growth and metabolism.     

Zinc Induced Changes in the Nucleic Acids and Protein Metabolism in the Fingerlings of a Freshwater Murrel,Channa punctatus

Fingerlings of Channa punctatus, a freshwater murrel, when subjected to a sublethal concentration of 12 mg l^?1 zinc for 20 days elicited a significantly decreased (P<0.01) RNA content and hypoproteinemia in their liver. However, an exposure for 10 days under the same condition did not produce a significant alternation (P>0.05) neither in the nucleic acids (RNA – DNA) nor in the protein content. Results are discussed in relation to the pollutional stress of this heavy metal.     

Acute Toxicity of Some Industrial Effluents in Relation to the Fish Size of Cyprinus carpio (HAM.) and Channa punctatus (BLOCH)

The fish Cyprinus carpio (HAM.) and Channa punctatus (BL.) of the size ranging between 6.0 ± 1.2 cm and 28.0 ± 1.6 cm were exposed to different concentrations of industrial effluents from M/s Punjab Tannery Ltd. (Jalandhar), M/s Spinning Mill Ltd. (Hoshiarpur) and M/s Food Specialist Ltd. (Moga) for evaluating the influence of fish size on the acute toxicity of these effluents. Results indicate that the relative toxicity of the effluents decreased with the increase in fish size from 6.0 ± 1.2 cm to 20.6 ± 1.5 cm. However, for specimens of the size of 28.0 ± 1.6 cm and more, the toxicity of the effluents increased with an increase in fish size. On the basis of the relative toxicity to fish, effluent from Punjab Tannery was found highly toxic and from Food Specialist Industry, the least toxic.     

Varied impact of land use on water and sediment parameters in fish ponds of the Dombes agro-ecosystem,France

Abstract

Agricultural land use in the area of water bodies is generally considered to increase the nutrient status of the water body water and sediments, but is this also the case for already nutrient-rich fish ponds? We studied 83 fish ponds in the Dombes region, France, where 1100 ponds are located in a heterogeneous agricultural landscape. Different water and sediment parameters were analysed for ponds and in ditches after rainfall events. Land use was studied in the primary catchment of ponds and in a 100-m zone around ponds. Soil parameters of different land-use types were analysed and farmers interviewed about agricultural practices. Increasing cropping area in the catchment of the ponds is significantly correlated to higher PO₄ ^3- concentration of pond water and to a lower degree, also to NO₃ ^?, but only in certain years with higher rainfall and with a more uneven distribution in spring. Sediment parameters were not significantly influenced. High NO₃- concentration in the water of a ditch during significant rainfall events was found for a cropland dominated catchment.

Citation Wezel, A., Arthaud, F., Dufloux, C., Renoud, F., Vallod, D., Robin, J., and Sarrazin, B., 2013. Varied impact of land use on water and sediment parameters in fish ponds of the Dombes agro-ecosystem, France. Hydrological Sciences Journal, 58 (4), 854–871.     

Explaining the thinness of the fresh water lens in the Pleistocene carbonate aquifer on Andros Island, Bahamas

Two hypotheses are explored to explain the thinness of the fresh water lens on Andros Island, Bahamas. The lens is an order of magnitude thinner than predicted by the Ghyben-Herzberg theory. One hypothesis previously posed in the literature is that the base of the lens is governed by the contact between the Lucayan Formation and the pre-Lucayan limestones. An alternate hypothesis, posed here, is that thinning is caused by the hydraulic influence of low-permeability paleosols in the Lucayan Formation. These hypotheses were explored, along with the influence of recharge and other factors, using a numerical model for variable-density flow and salt transport. In the layered system of grainstones/packstones and paleosols within the Lucayan Formation itself, the velocity vectors are nearly horizontal in the grainstones/packstones, and they are nearly vertical in the paleosols. These strata above the pre-Lucayan, all lower than it in permeability, draw the base of the lens upward to a position well above the contact by significantly reducing pressure within and below the strata relative to hydrostatic pressure. It is the loss of pressure across the paleosols that dramatically thins the fresh water lens, and thus the predominant hydraulic control on lens thickness arises from the existence of paleosols.     

Determination of petroleum hydrocarbons in water, fish and sediments following the Ekofisk blow-out

Samples of fish, water and sediment were collected during the Ekofisk ‘Bravo’ blow-out and analysed for specific aliphatic and aromatic hydrocarbons. Analyses showed the presence of petroleum hydrocarbons from the blow-out in some of the water samples, but fish and sediments, collected up to a week after it began, showed no evidence of a contribution from the blow-out.     

Caffeine and agricultural pesticide concentrations in surface water and groundwater on the north shore of Kauai (Hawaii, USA)

Caffeine has been associated with wastewater pollution in temperate and subtropical locations, but environmental caffeine concentrations in tropical locations have not been reported. The objectives of this study were to measure caffeine and agricultural pesticide (carbaryl, metalaxyl, and metribuzin) concentrations in environmental waters on the tropical north shore of Kauai (Hawaii, USA) and assess whether patterns in caffeine concentration were consistent with a wastewater caffeine source. Groundwater, river, stream and coastal ocean samples were collected in August 2006 and February 2007. Caffeine was detected in all August 2006 samples and in 33% of February 2007 samples at concentrations up to 88 ng L⁻¹. Metribuzin was detected in five samples collected in February 2007. Carbaryl and metalaxyl were not detected in any sample. Caffeine was not detected in offshore ocean samples or river samples upstream of human development. A positive correlation between caffeine and enterococci suggested a possible wastewater caffeine source.     

Distribution of polychlorinated biphenyls in the water, sediment and fish from the Pearl River estuary, China

The concentrations and distribution of polychlorinated biphenyls were determined in water, surface sediments and fishes from the estuaries of Pearl River, PR China. The results showed that the concentrations ranged from 2.47 ng l-1 to 6.75 ng l-1 in water, from 11.13 ng g-1 to 23.23 ng g-1 in sediments (dry weight) and from 68.64 ng g-1 to 316.85 ng-1 in fish (lipid weight). It was found that the feeding habits of fish were very significant in the accumulation of polychlorinated biphenyls and pattern of congeners. Carnivorous and benthic fishes such as eel (Anguilla japonica) and Chinese sea catfish (Arius sinensis) were found to have high concentrations of polychlorinated biphenyls and of high-chlorinated congeners, while herbivores such as shad (Clupanodon punctatus) and mullet (Mugil cephalus) exhibited an opposite trend. Congeners IUPAC Nos. 153, 138, 118, 87/81, 170 and 52 were found frequently in most samples (both sediment and fish). In comparison with other places in the world, the concentration of polychlorinated biphenyls in sediment and fish from the estuary of Pearl River were low.     

低头坝养鱼对上下游局域栖息地和鱼类群落时空格局的影响

河流鱼类的群落特征会随栖息地环境的变化而发生变化.为了解鱼类群落对低头坝养鱼的响应程度,2013—2014年共6次调查了乌龙河(长江下游支流)两个可涉水河段样点(上游坝和下游坝)的环境因子、鱼类多样性及其群落结构.共采集到5目10科21属24种鱼类,以鲤形目鲤科最多,占总数的58.3%.通过解析时空动态变化与局域栖息地条件对鱼类群落的影响,发现季节因素对鱼类群落结构无显著影响,而鱼类群落所在空间位置(上游坝,下游坝)对群落结构差异具有较显著影响,其中上游中华鳑鲏(Rhodeus sinensis)、(Hemiculter leucisculus)、棒花鱼(Abbottina rivularis)、大鳍鱊(Acheilognathus macropterus),下游食蚊鱼(Gambusia affinis)的多度决定了这种差异;而3个栖息地变量(溶解氧浓度、电导率和流速)均对鱼类群落特征具有显著性影响.栖息地环境差异对河流上、下游鱼类群落的影响较大,具体体现在下游样点鱼类的捕获重量、捕获数量、密度、多样性明显下降,推测利用低头坝养鱼是造成这些现象的重要原因.     

Changes in algal, coral and fish assemblages along water quality gradients on the inshore Great Barrier Reef

Macroalgae, hard corals, octocorals, and fish were surveyed on 10 to 13 inshore coral reefs of the Great Barrier Reef, along a water quality gradient in two regions with contrasting agricultural land use. A water quality index was calculated for each reef based on available data of particulate and dissolved nutrients, chlorophyll and suspended solids. Strong gradients in ecological attributes occurred along the water quality gradient. Macroalgae of the divisions Rhodophyta and Chlorophyta increased with increasing nutrients, while Phaeophyta remained similar. Octocoral richness and abundances of many hard coral and octocoral taxa decreased, and none of the hundreds of species increased. At reefs in higher nutrient environments, hard coral and octocoral assemblages were composed of subsets of the many species found in lower nutrient environments, whereas fish and macroalgal assemblages consisted of contrasting suites of species. The study identifies species groups that are likely to increase or decrease in abundance with changing water quality.     

Application of food waste based diets in polyculture of low trophic level fish: Effects on fish growth,water quality and plankton density

Food waste was collected from local hotels and fish feed pellets were produced for a 6 months long field feeding trial. Three types of fish feed pellets (control diet: Jinfeng® 613 formulated feed, contains mainly fish meal, plant product and fish oil; Diet A: food waste based diet without meat and 53% cereal; Diet B: food waste based diet with 25% meat and 28% cereal) were used in polyculture fish ponds to investigate the growth of fish (grass carp, bighead and mud carp), changes in water quality and plankton density. No significant differences in the levels of nitrogen and phosphorous compounds of water body were observed between 3 fish ponds after the half-year feeding trial, while pond receiving Diet A had the highest density of plankton. The food waste combination of Diet B seems to be a better formulation in terms of the overall performance on fish growth.     

Seasonal and spatial variability of water quality parameters in the Port of Genoa, Italy, from 2000 to 2007

This paper presents the results of the statistical analysis of a set of physico-chemical and biological water quality parameters, monthly collected from 2000 to 2007 in the Genoa Harbour area (Ligurian Sea). We applied multivariate methods, such as principal component analysis (PCA) and dynamic factor analysis (DFA) for investigating the spatial and temporal variability and for providing important background information on pollution problems in the region. PCA evidenced the role of the sewage and river discharges and of the exchanges with the open sea in determining the harbour water quality. DFA was used to estimate underlying common trends in the time series. The DFA results partly show a general improvement of water quality over the 8-years period. However, in other areas, we found inter-annual variations but no significant multi-annual trend. Furthermore, we included meteorological variables in our statistical analyses because of their potential influence on the water quality parameters. These natural forcings explain part of the variability in water quality parameters that are superimposed on the dominating anthropogenic pollution factors.     

The effects of soil organic matter on soil water retention and plant water use in a meadow of the Sierra Nevada,CA

Tuolumne Meadows is a groundwater dependent ecosystem in the Sierra Nevada of California, USA, that is threatened by hydrologic impacts that may lead to a substantial loss of organic matter in the soil. In order to provide a scientific basis for management of this type of ecosystem, this paper quantifies the effect of soil organic content on soil water retention and water use by plants. First, we show a substantial dependence of soil water retention on soil organic content by correlating Van Genuchten soil water retention parameters with soil organic content, independent of soil texture. Then, we demonstrate the impact of organic content on plants by simulating the degree to which root water uptake is affected by soil water retention with the use of a physically based numerical model of variably saturated groundwater flow. Our results indicate that the increased water retention by soil organic matter contributes as much as 8.8 cm to transpiration, or 35 additional water‐stress free days, during the dry summer when plants experience increased water stress.     

Evaluation of building fundamental periods and effects of local geology on ground motion parameters in the Siracusa area,Italy

The Siracusa area, located in the southeastern coast of Sicily (Italy), is mainly characterized by the outcropping of a limestone formation. This lithotype, which is overlain by soft sediments such as sandy clays and detritus, can be considered as the local bedrock. Records of ambient noise, processed through spectral ratio techniques, were used to assess the dynamic properties of a sample survey of both reinforced concrete and masonry buildings. The results show that experimental periods of existing buildings are always lower than those proposed by the European seismic code. This disagreement could be related to the role played by stiff masonry infills, as well as the influence of adjacent buildings, especially in downtown Siracusa. Numerical modeling was also used to study the effect of local geology on the seismic site response of the Siracusa area. Seismic urban scenarios were simulated considering a moderate magnitude earthquake (December 13th, 1990) to assess the shaking level of the different outcropping formations. Spectral acceleration at different periods, peak ground acceleration, and velocity were obtained through a stochastic approach adopting an extended source model code. Seismic ground motion scenario highlighted that amplification mainly occurs in the sedimentary deposits that are widespread to the south of the study area as well as on some spot areas where coarse detritus and sandy clay outcrop. On the other hand, the level of shaking appears moderate in all zones with outcropping limestone and volcanics.     

Quantifying the effects of climate change and human activities on runoff in the water source area of Beijing,China

Abstract

Quantitative assessment of the effects of climate change and human activities on runoff is very important for regional sustainable water resources adaptive management. In this study, the non-parametric Mann-Kendall test is used to identify the trends in and change points of the annual runoff with the aim of analysing the changing characteristics of the hydrological cycle. The study presents the analytical derivation of a method which combines six Budyko hypothesis-based water–energy balance equations with the Penman-Monteith equation to separate the effects of climate change and human activities. The method takes several climate variables into consideration. Results based on data from the Yongding River basin, China, show that climate change is estimated to account for 10.5–12.6% of the reduction in annual runoff and human activities contribute to 87.4–89.5% of the runoff decline. The results indicate that human activities are the main driving factors for the reduction in runoff.

Editor Z.W. Kundzewicz; Associate editor C.Y. Xu     

A terrestrial observatory approach to the integrated investigation of the effects of deforestation on water,energy,and matter fluxes

Integrated observation platforms have been set up to investigate consequences of global change within a terrestrial network of observatories(TERENO)in Germany.The aim of TERENO is to foster the understanding of water,energy,and matter fluxes in terrestrial systems,as well as their biological and physical drivers.Part of the Lower Rhine Valley-Eifel observatory of TERENO is located within the Eifel National Park.Recently,the National Park forest management started to promote the natural regeneration of near-natural beech forest by removing a significant proportion of the spruce forest that was established for timber production after World War II.Within this context,the effects of such a disturbance on forest ecosystem functioning are currently investigated in a deforestation experiment in the Wüstebach catchment,which is one of the key experimental research sites within the Lower Rhine Valley-Eifel observatory.Here,we present the integrated observation system of the Wüstebach test site to exemplarily demonstrate the terrestrial observatory concept of TERENO that allows for a detailed monitoring of changes in hydrological and biogeochemical states and fluxes triggered by environmental disturbances.We present the observation platforms and the soil sampling campaign,as well as preliminary results including an analysis of data consistency.We specifically highlight the capability of integrated datasets to enable improved process understanding of the post-deforestation changes in ecosystem functioning.     

海南琼海加积井水温同震效应特征和机理初探

基于海南加积井数字化水温2007年1月-2010年4月震中距小于8 000 km、Ms≥7.8大震的同震响应资料,系统分析水温年月日正常动态特征,发现远震引起的水温同震效应特征为上升脉冲,与以往的非自流井水温同震效应以下降为主的认识不一致;水温变化幅度与震中距、震级有一定关系,加积井水温同震效应成因,可用“层内混合”作...