Abstract:Statistics on the status and trends in numbers of waterbirds are necessary for the conservation of their wetland habitats.Waterbirds are also considered as one of the indicators of habitat quality of wetlands.We reviewed the studies on the ecological relationships between waterbirds and lake ecosystems, and found that abundance and species richness of waterbirds could respond quickly to the biomass change of macrophytes and fishes, as well as variation of water level, trophic status of lakes, and colonial fish-eating birds could be used to monitor the level of persistent toxic substances in lakes.In turn, waterbirds could impose a significant impact to lakes through grazing on aquatic vegetation, and nutrient load by faecal deposition.In addition, management of lake ecosystems related to waterbirds was suggested accordingly.In order to have a better understanding of the factors that lead to switches between multiple stable states in eutrophic lakes, and on the restoration progress eutrophic lakes, waterbirds should be incorporated into monitoring of eutrophic lakes in the process of lake restoration in China, and additional studies to quantify the relationships between waterbirds and macrophytes, fish and environmental variables of lakes are necessary.

Abstract:Riverine transport is the principal pathway of dissolved elements from land to the sea.Based on the quantitative analysis of human effects on the phosphorus cycling within the Yangtze River basin, we estimated the exports of dissolved inoiganic phosphorous (DIP) from the Yangtze River to the estuary for the period 1970-2003, by using the Global NEWS-DIP model.Modeled DIP export increased from 2.45kg/km² in 1970 to 14.05kg/km² in 2003 under the enhancing anthropogenic activities.No significant difference between the modeled and measured values at the level of P=0.05 is observed, and the average model error is 12.29%.Diffuse sources (including chemical fertilizer application and animal manure P input) had contributed the most in DIP export since 1993.The contribution varied between 58.60% and 75.48%.Sewage discharge was the major source of river DIP export before 1993, with the contribution varying between 99.98% and 45.21%, while the contribution decreased rapidly since then until to 24.81% in 2003.We also discussed possible future trajectories of DIP export based on the MEA scenarios.How to control the diffuse nutrient inputs under enhancing human pressures will be a long-term and urgent task.

Abstract:The Laoha River catchment, Liaohe River Basin in the semi-arid region of northern China is selected for study.The interception evaporation, canopy transpiration and soil evaporation are computed by a physically-based two-source potential evapo-transpiration model in each grid cell of the basin.The calculated potential evapotranspiration is regarded as the input of the hybrid runoff model instead of the pan evaporation.Then the grid-based distributed hydrologic model is built for daily runoff simulation during 1970-1979 in the target basin by coupling the two-source PET model in the hybrid runoff model framework.The results show that the two-source PET model can reflect the effects of vegetation type, vegetation physiological features and phonological characteristics on the evapotranspiration.And the grid-based distributed hydrologic model which can illuminate the rule of runoff generation and runoff routing is applicable for runoff simulation in the target basin.

Abstract:The currently global climate changes characterized by increasing temperature have the potential to alter the hydrological cycle in regional and global scale.The intensifying meteor-hydrological extremes should be due to altered hydrological cycle.Sound understanding and good knowledge of probability behaviors of meteor-hydrological extremes are the first step into effective management of resources and enhancement of human mitigalion to natural hazards.In this case, the multivariate analysis method and the Copula function are used in this study with aim to investigate joint probability behaviors of high flow and low flow of the major tributaries of the Lake Poyang, the largest freshwater wetland in China.The results indicate that:(1) The joint return periods (JP) of high and low flows are shorter than the designed ones.However, the joint return periods given X>x and Y>y (JPS) are much longer than the designed ones.(2) Given the same designed return periods, the JPs of high flow at the Waizhou and Lijiadu stations are larger than those of low flow events.Besides, the JPSs of high flow are usually shorter than those of low flow, implying higher probability of high flow events at the Waizhou and Lijiadu stations.The probability of concurrent occurrence of high flow with return periods of < 10 years is larger than that of > 10 years.The JPs and JPSs of high flow and low flow events at the Hushan and Lijiadu stations are approximately similar, implying the similar probability of concurrent occurrence of high and low flow e-vents.(3) Given the same designed return periods, the JPs (JPSs) of high flow events at the Waizhou and Lijiadu stations are larger (smaller) than those at the Hushan and Dufengkeng stations.The JPs (JPSs) of low flow events at the Waizhou and Lijiadu stations are smaller (larger) than those at the Hushan and Dufengkeng stations.

Abstract:Operation of the Hiree Gorge Project will change the hydrological processes and affect the ecosystem of lake wetland.The two time periods, i.e.water storage after flood season and water emptying before flood season, with highly changed water regime are selected to evaluate the effects of the Three Gorge Reservoir regulation by using the hydrodynamic method.The lake water levels and discharge variations are computed under the different regulation c￡ discharge values.Gombined with lake level variations and the elevation-area curve, the wetland exposure area are also analyzed.Results show that lake level of the Lake Poyang (at Duchang Station) would decrease 0.09-1.11m for steady flow condition if the discharge of Yangtze river decreases 1000-7653m³/s after flood season, whereas lake level will increase 0.15-0.94m if the dischaige increases 1000-6500m³/s before flood season.The effect of Three Gorge Reservoir on lake levels varies significantly from northern to southern part of the lake, which are depended on the hydrodynamic cainectivity conditions.

Abstract:Lake Xingkai is a boundary lake between China and Russia.Based on monitoring and statistical data in the Big Lake Xingkai, the average value of COD_Mn was 5.42mg/L, B0D₅ was 1.59-2.91 mg/L, TP was 0.35mg/L during the 1994-1998 period, which was meso-eutrophic lake.Based on the monitoring report in the Big Lake Xingkai in 2009, the average value of C0D_Mn was 4.09mg/L, the average of NH₄-N was 0.466mg/L.The water quality standard decreased from Grade Ⅱ to Grade Ⅲ and was further degraded.During the 2005-2009 period based on monitoring data from Astrakhanka of Russia, the major pollution was organic pollutants, in which COD_Mn was 11.5-16.2mg/L and TP was 0.046-0.266mg/L.The results indicated that water quality was deteriorated and had eutrophication tendency.The industrial and tourism sewage seriously influenced on water environment, and the water environment safety faces certain pressures.This article analyzed the threats and provided the feasibility countermeasures for protecting waters of Lake Xingkai.

Abstract:Five kinds of wetland plants, including reed (Phragmites australis), oriental cattail (Typha orientalis), calamus (Zizania aquatica), wildrice stem (Acorns calamus), Iris (Iris temufolia), and one kind of shrub of willow (Salix viminalis) were selected to study the growth characteristics of plants and the role of removing nitrogen and phosphorus in severe eutrophic waters.The study showed that the six kinds of plants in experiments grew well and steadily.After 105 days, the total biomass ranged from 424 to 1772g/m².Ratios of most plant biomass above/below ground (A/U) varied between 0.63 and 1.49, except for oriental cattail (A/U:3.23).Concentrations of nitrogen and phosphorus in the biomass of above ground ranged from 13.12 to 28.83mg/g and frwn 1.55 to 3.77mg/g, respectively.Concentrations of nitrogen and phosphorus in the biomass below ground ranged from 7.76 to 15.60mg/g and from 1.70 to 2.71mg/g, respectively.The concentrations of nitrogen and phosphorus between alaove and below ground biomass differed significantly.The average plant accumulations of nitrogen and phosphorus were 20.60g/m² and 3.08g/m², which the above ground accounted for 66.60% and 58.22%, respectively.Purification efiect of the plants on dififerent pollutants was different.The best purification effects for TN in Iris and TP in reed were found.Plant accumulations of nitrogen and phosphorus displayed significantly positive linear correlation with plant biomass and concentrations of nitrogen and phosphorus.

Abstract:Lakes in desert areas are very different from large lakes in the eastern part of China, like Lake Taihu.The objective of this study was to find out the optical properties of desert lakes.Reflectance spectra were measured in October 2009 with ASD Field-Spec spectrometer.Concurrently, water samples were collected directly from the lake to be analyzed in laboratory.After correlation analysis between the TDS and concentration of chlorophyll-a, DOC, TSM, comparing absorption spectra of NPSS, CDOM, chlorophyll-a, and discussion of the remote sensing reflectance in different wave bands, the result shows TDS and water depth are the main influence of IOPs and AOPs.The TDS has influenced the absorption properties remarkably and has high correlation coefficient with the concentration of DOC and with absorption of CDOM in 240-300nm.Water depth is most important factor of remote sensing reflectance, and TDS plays a major role in 550-720nm within the same water depth ranges.These conclusions may provide useful RS basis to estimate water quality parameters in desert iakes.

Abstract:Both radiative transfer model and bio-optical model can be used to simulate the remote sensing reflectance for waters.Generally, the radiative transfer model is of high accuracy, but it is too sophisticated to retrieve water quality parameters (WQPs).The bio-optical model is simple and easy to be implemented in retrieving WQPs, but its accuracy in simulating turbid case Ⅱ waters is still unknown.In this study, the radiative transfer model (i.e.Hydrolight model) and bio-optical model (i.e.Lee model) were both used to generated a large number of spectra data with different combinations of WQPs.Using the spectra yielded by Hydrolight model as true value, we assessed the simulation accuracy of the Lee model in turbid case Ⅱ waters.Results show that (1) except for the non-phytoplankton suspended substance dominated waters, results of Lee model can be acceptable with overall relative error less than 10%;(2) larger errors in Lee model occurred in the bands for Chl.a estimation than other bands;(3) simulation accuracy of remote sensing reflectance just below water surface is consistent with thal just above surface.

Abstract:An experiment that Microcystis aeruginosa was exposed to short-term (0-24h) simulated UV-B radiation was carried out to determine the effect of increased UV-B radiation on the phytoplankton growth in lakes, especially lakes in the mountain and plateau.By measuring the biomass, physiological and ultrastructural indices, the response of M.aeruginosa to UV-B radiation was analyzed.When the UV-B radiation exposure time reached to lh, the M.aeruginosa began to die, but the protein concentration increased and chlorophyll-a concentration remained stable.When the UV-B radiation exposure time was less than 4h, the activity of superoxide dismutase (SOD) enzyme remained high, the cell membrane was in good condition, and the number of thylokoids and cyanophycin granules remained stable.When the UV-B radiation exposure time was more than 4h, chlorophyll-a concentration and the activity of SOD enzyme of M.aeruginosa started to rapidly drop.The UV-B continuous radiation exposure time reaching to 4h was the maximum resistance of M.aeruginosa.

Abstract:According to the in situ measured data on 32 sampling sites in Lake Chaohu in June 2009, the spectral characteristics of diffuse attenuation coefficient (K_d), dominant factors, spatial distribution, as well as the relationship between K_d and K_d (490) in 400-700nm bands were analyzed.On the basis of these analysis, remote sensing inversion model was developed to calculate K_d (490).The results indicate that presented the consistent spectral characteristics.The K_d in 400-600nm showed a exponential decay trend, but K_d from 600nm to 700nm didn't correlate with wavelength.Due to the higher concentration of phytoplankton in some locations, peak values of K_d appeared at 675nm;but K_d showed a feature that was similar to that of pure water in 700-900nm.The dominant factor of diffuse attenuation coefficient was inorganic particles in Lake Chaohu, organic particles took the second place, and CDOM held a minimal impact.In general, K_d(490) in the eastern part of the Lake Chaohu was higher than that in the western part.In the central part, the contour lines of K_d(490) were denser than those in other parts of the lake.K_d(490) was inversed by multivariate linear regression model established with R_rs(591), R_rs(702) and R_rs(842).And the average relative error between measured and in versed K_d (490) was 7.85%.At the same time, the relationship between K_d(λ, λ≠ 490nm) and K_d(490) could be parameterized with wavelength by linear formula in 400-550nm.From 550nm to 700nm K_d(λ, λ≠490nm) was obtained from multiplying K_d(490) by a constant.The relative error between the observed K_d and the K_d(λ), which was calculated by K_d(490) by inversing of the R_rs, was 6.14%.

Abstract:Species composition, cell density, Shannon-Weaver diversity index, community structures of benthic diatoms and standing crops of benthic algae were investigated in the littoral zone of 21 shallow lakes in Hubei Province, and the water quality was evaluated combined with chemical parameters.The standing crops(Chl.a) of benthic algae and the density of benthic diatoms, with the range of 1.01-40.82μg/cm² and 0.09 ×l0⁶-14.20×10⁶cells/cm², respectively, exhibited higher values in eutrophic lakes during the studying period.Among the 181 taxa (variety) of benthic diatom observed, Achnanthes minulissima distributed widely and was absolutely dominant or sub-dominant species in mesotrophic and meso-eutrophic lakes.The results of two-way indicator species analysis and detrended correspondence analysis catalogued these lakes into three groups:the dominant species were taxa of Achnanthes genus in meso-eutrophic lakes of the first group;several dominant species existed at the same time in mesotrophic lake of the second group;the third group were the city eutrophic lakes.Nanhu was hyper-eutrophic lake, Gomphonema parvulum was dominant indictor(43% of relative abundance).

Abstract:The fish species diversity and community structure in Hukou area of Lake Poyang were investigated from October 2006 to March 2009.A total of 50 species was classified into 6 orders, 12 femilies and 42 genus.Eesis fish was dominated in the fish species, and none of migration diadromous fish.Among the composition of catches collected in Hukou area of Lake Poyang, Pelteobagrus nitidus, Hemiculter leucisculus and Coilia brachygnathus were the most abundant species.Seasonal variations of average fish amounts captured by set nets were ranked from higher to lower as follows:summer, autumn, spring and winter.Generally, the changes of species abundance and quantity were positively correlated with water level and water temperature.Shannon-Wiener index was relatively lower, ranged from 1.16 to 2.58, and below 2 in most months.At the present time, fishing operation by set nets was very widespread in Hukou area of Lake Poyang, Commercial species had a lower proportion in catches and most of them were small individuals.Thus the management and protection of fish resources should be strengthened immediately in the area.

Abstract:Fifteen species of planktonic crustaceans, including 7 species of copepod and 8 species of cladoceran, were identified in an investigation for seven reservoirs of Hainan Island in the dry season (December, 2006) and flooding season (May, 2007).All the species were eurythermal or mesophilic, and their communities were dominated by small-sized species.Mesocyclops thermocyclopoides, Bosmina fatali and Bosminopsis deitersi were common species in all the reservoirs.The species richness, in the oligotrophic and oligo-mesotrophic reservoirs were much higher in flooding season than in dry season, but had a reverse pattern in the eutrophic reservoirs.The abundance of Bosmina fatali and Diaphanosoma dubium was positively related with majority of species, and Thermocyclops taihokuensis and Mesocyclops thermocyclopoides were negatively but weakly related with the cladoceran species in correlation analysis.This weak correlations indicated a weak interaction between the species and other influence factors existed, such as fish predation affected coexistence of planktonic zooplankton species.

Abstract:Lake Dishui is a man-made lake which was excavated in the reclaimed beach land, Shanghai.The study analyed monthly sampled rotifer from the lake between 2008 and 2009 to understand the dynamic features of planktonic rotifer.We also studied the specific composition, abundance and related ecological variables of rotifers.Altogether 33 species of rotifers, belonging to 12 genera were identified.The dominant species were including Brachionus calyciflorus, B.angularis, Trichocerca rousseleti and Polyarthra sp.The rotifer abundance of annual varying was 58.3-1829.2ind./L.There was an extremely significant difference among the four seasons, but no significant difference among the sample stations.Apparently the abundance of rotifers in summer and autumn was higher than those in spring and winter, particularly the value in autumn was a maximum, averaged 1087.5 ind./L, The change of rotifer-abundance was mainly related to the variables, such as Chlorophyta biomass and temperature.

Abstract:The morphological variations of the reciprocal F₁ hybrids between Pelteobagrus vachelli and Pseudobagrus ussuriensis were analyzed by Chi-square analysis and multivariate data analysis methods based on the parameters of morphometric characters.The results of Chi-square analysis indicated that there were no significant differences between the reciprocal F₁ hybrids and their parents, except for the number of pectoral fin.The number of pectoral fin can be used as an important parameter to discriminate the reciprocal F₁ hybrids from their parents.In aspect of the characters of anal fin and caudal fin, there were significant differences between the reciprocal F₁ hybrids and their parents of P.vachelli, but not significant between reciprocal F₁ hybrids and their parents of P.ussuriensis.The results of cluster analysis have revealed that the morphometric characters of two female parent fish groups were much closer to the two male parent fish groups, as well to the reciprocal F₁ hybrids groups.Principal component analysis showed that the morphological differences of six experimental fish groups were induced by length discrepancy of fish body depth.Discriminant analysis indicated that the total discriminant accuracy of the discriminant functions was 97.9% in the six experimental fish groups.All results showed that the reciprocal F₁ hybrids appeared morphological diversity to some extent compared with their parents, and the reciprocal F₁ hybrids were much closer to P.ussuriensis in the aspect of morphology.

Abstract:The internal transcribed spacer 1 (ITS-1) of four common carp populations were amplified and sequenced.The result showed that the average contents of GC were obviously higher than that of AT in the aligned sequences of 370bp.Total 34 variable sites were detected, and 14 haplotypes were recovered.The haplotype diversity and nucleotide diversity were 0.637±0.055 and 0.00857±0.00200, respectively.The genetic distance between Heilongjiang carp and Jian carp displayed the highest, up to 0.10129, while that between Heilongjiang carp and Yellow River carp peculations was the lowest to 0.02305.The fixation indices (F_st) of analysis of molecular variance (AMOVA) among populations was 0.05373, which showed no significant population structure.Tlie phylogenetic tree of ITS-1 built with MEGA 4.1 showed that four common carp populations were clustered into two major clades based on genetic distance.Populations of Heilongjiang carp and Yellow River carp were clustered in northern clade, while Jian carp and Hebao red carp were clustered in southern clade.

Abstract:In order to study the reproductive biology of Gymnocypris waddellii Regan, we collected 225 fishes in Karuxung River and Rongbuk Zangbo River which are located in Yanmdrok region from March to July in 2006.The results show that G.waddellii Regan has anadromous habit and reproduces from May to August with water temperature of 9.5-18.5℃, flow rate of 0.3-0.8m/s and depth of 15-50cm.All female and male firstly start to reproduce at 5 ages and their secondary sexual features are significantly different between male and female.The smallest sex mature male with 80 g weight has mature coefficient of 4.6% with body length of 19.5cm.The smallest sex mature female with 95 g weight has mature coefficient 6.3% with body length of 21cm.Tile mature eggs are orange and round balls with diameter ranging from 1.92 to 3.32mm, and the mean diameter of mature eggs is 2.22mm.The number of eggs within one gram varies from 63 to 214 eggs with mean of 115 eggs.The absolute fecundity of brood stocks varies from 1086 to 11400 eggs and the mean is 4446 eggs.The relative fecundity varies from 6.2 to 36.1 eggs/g with mean of 18.0 eggs/g.The mature coefficient varies from 5.7% to 25.8% with mean of 16.2%.The brood stocks are composed mainly of individuals aged 8, 9 and 10 with sex ratio of females to males of 1:1.16.Fecundity was positively correlated with body length and weight, respectively.

Abstract:Callus of Alternanthera philoxeroides was cultured by tissue culture technique, which was used as experimental material.This paper studied the toxic effects of Pb²⁺ gradient concentrations (0, 0.2, 0.4, 0.8 and 1.6 mmol/L) on the contents of photosynthetic pigments and soluble protein, the level of active oxygen, activities of antioxidase(GAT, SOD and POD) and changes of ultrastructure in callus of Alternanthera philoxeroides.Tlie results indicated that, with the increasing of Pb²⁺ concentration, the contents of photosynthetic pigments and soluble protein decreased gradually.The contents of O₂^- and H₂O₂ increased gradually, while the content of MDA increased at first and then decreased.TTie changes of SOD and POD activities were the same as MDA, but CAT activity decreased gradually.Transmission electron microscopy observation showed that the chloroplast, mitochondria and nucleus suffered serious damages under Pb²⁺ stress, and the concentration of 0.8-1.6mmol/L generated the fateful poisons to ultrastructure.It was concluded that Pb²⁺ stress induced not only destruction of physiological function and structural foundation of Alternanthera philoxeroides callus, but also the disorder of physiological metabolism, which led to the death of the callus at last.

Abstract:Using an X-ray Fluorescence (XKF) core scanner, chemistry features of bulk sediment can be measured directly which does not destruct sediment surface nor split sediment cores.Tliis method has been potentially and widely applied to ewe sediment analysis, but little is known about the effects of sediment physical properties on XRF core scanner measurements.Comparison of intensities obtained by XRF and the chemical concentration measured by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), indicates effects of physical properties varied from different elements on elemental intensities in the lacustrine sediments of a core from Zigetang Co in the central Tibetan Plateau.Correlation among elements K, Ca, Ti, Cr, Mn, Fe and Sr between the two measurement methods of the XRF and the ICP-OES is high, but the correlation is low for element sulfur.This indicates that XRF measurements for non-metal elements such as sulfur, which has a multi-chemical valence, could be strongly affected by sediment properties.Comparing the ratios between element intensities and concentration, we found that the lower XRF element intensities were related to the amount of water.Using the intensity of Cl as an indicator of water content, the element intensities of K, Ca, Ti and Fe in the core samples were corrected.TTie correlation coefficients of each pairs of the two datasets among K, Ca, Ti and Fe were significantly raised.These data sets with highly correlations were used to produce a transfer function to relate XRF element intensity with element concentration.Calculated element concentrations from the intensities show only minor differences from concentrations obtained by ICP-OES, indicating XRF core scanners are a very useful tool for measuring element concentration in lacustrine sediments.

Abstract:We hand-excavated a profile named QTH02 in a terminal lake in Shiyang River, Lake Zhuye.The QTH02 was sampled at 2cm intervals in which 368 samples were yielded for analysis of grain-size, and sampled at 10cm intervals in which 74 samples were yielded for pollen analysis.Based on the correlation analysis, the results showed that the variables between sensitive components of the grain-size and pollen assemblages are related with each other.The total pollen concentration and percentages of Ephedra, Nitraria, Chenopodiaceae, Typha and Picea are positively correlated with the grain-size sensitive components that the sizes are less than 89.31μm, and negatively correlated with the grain-size sensitive components that the sizes are larger than 89.31 μm.The percentages of Betula, Quercu, and Urtica are positively correlated the grain-size sensitive components that the sizes are more than 89.31μm.The correlation between the pollen assemblages and grain-size sensitive components is mainly controlled by the moisture conditions of the basin and water level of the Lake Zhuye, which is also affected by wind transportation.The pollen proxies which are correlated with the fine components are mainly affected by the hydrodynamics of the drainage basin and high lake-level, and the pollen proxies which are correlated with the coarse components are mainly affected by low lake-level and eolian activities.While the drainage basin is relatively humid and the lake-level is relatively high, the total pollen concentration and percentages of river-transported pollen are relatively high.While the drainage basin is relatively arid, the total pollen concentration is relatively low, but the percentages of wind-transported pollen are relatively high.Then, based on the relationships between the grain-size sensitive components and polien assemblages, we divided the climatic and environmental changes in Lake Zhuye since the Late Clacial into six stages.The climate is moist in the Early and Middle Holocene but dry in the Late Clacial and Late Holocene.

Abstract:The Faiyum Depression, a flood plain of the Nile downstream, receives sediments from the Nile and the Sahara Desert.By means of grain size and magnetic susceptibility analysis of sediments from core FYAM (4.6m deep), combined with surficial characteristic of quartz grains, occurrence of gypsum and carbonate contents, the paper is aiming to reveal some indicators for eolian activity in the Faiyum sediments.The results suggest that there are totally seven patterns of sediment grain-size distribution, including unimodal and biomodal patterns composed of a fine-grain peak (6-20μm) and a coaree-grain peak (80-lOOμm).These patterns have a close relation to magnetic susceptibility except for the sediments of two layers with high or low magnetic susceptibility caused probably by human activity and carbonate content.When the coarse-grain peak appears as a major pattern, the sediments are characterized by low magnetic susceptibilities, implying eolian quartz content increased, and strong sandstorms.When the fine-grain peak is dominated, the sediments were consistent with high magnetic susceptibility and less eolian quartz grains, probably revealing increasing sediment supply from the Nile.