Abstract:Natural organic matter is an important component in terrestrial surface environment. More and more researches indicatedthat it plays an important role in physical, chemical and biological processes of terrestrial ecosystem;it is the important cycling routesof matter and energy and relates with nearly all the important links of ecosystem. Natural organic matter is not only the importantstudy field of biogeochemistry, ecology and environment sciences, but also a basic theoretical area in the assessment, prediction andcontrol of environment pollution. Natural organic matter now becomes the focus of environment quality, toxicology, environment lawand management. Using fresh lake and river as examples, this article briefly summarizes the study results of sources, chemicalstructure, cycling characteristics, coupling relations with nutrients cycling, and its effects on mobility and transformafion of toxicmetals and organic pollutants, and expounds the possible right research directions and contents referring to water eutrophication andenvironment pollution. This article also makes a prospect about modern organic environment and biogeochemistry.

Abstract:Stable isotope analysis is commonly used in studying flows of mass and energy through food webs and trophicrelationships in aquatic ecosystems. However, different sample processing methods can influence the measurement of these stableisotope rates, which may result in errors in the resulting food web models and the comparing results between different studies. Inparticular, errors may result from four different sources, that is, preservation, separation, acidification and dehydration. The collecttedparticulate/dissolved organic matter, bacteria, zooplankton, algae, hydrophyte, fish and zoobenthos were rinsed with deionized waterto clean off epibionts, and then stored at ?20℃. Acidification by adding 1mol/L HCl drop-by-drop was needed for carbon isotopeanalysis in samples of sediment organic matter, invertebrates with calcareous structures, and plankton. For nitrogen analysis,acidification should be avoided. Finally, dehydration was required by the analytical methods used in the determination of isotopicabundance. Both freeze-drying and drying at 40?70℃ were acceptable. In addition, materials preserved with formalin and ethanolstocks was suitable for current ecological applications of isotopic analysis and open up the possibility to reconstruct food webs andbiogeochemical changes at scales of tens or hundreds of years. In this review we summarize different sample processing prior to theanalytical determination of stable isotope ratios and the influence mechanism of some processing methods, which are fundamentalfor further methodology research.

Abstract:As the third largest freshwater lakes of China and seriously suffered by Microcystis algal bloom in recent 20 years, LakeTaihu's eutrophic status had been analyzed based on the monthly monitoring data in recent 5 years. The analysis indicated thateutrophication of Lake Taihu became more and more serious since 2000. Comparing to the mean values in recent 5 years, the waterquality variables like total nitrogen, total phosphorus, and transparency, water quality of Lake Taihu were worse than that between1991 and 2001. The summer mean of TN between 2002 and 2006 was significantly higher than that of between 1992 and 2001 (p =0.005). And the transparency mean of summer of 2002-2006 in center of Lake Taihu was only 0.34 m, which was significantly lowerthan that of 1992-2001 with a mean 0.63 m (p = 0.003). Moreover, Microcystis blooming areas in summer increased from about onefourth of the lake before 2000 to over half of the lake in 2006. Blooming season from June to October before 2000 also extend fromMay to December in 2006. Microcystis blooms occur more and more regularly in the lake. And dominant areas of submergedmacrophytes decreased quickly. The deteriorate trend of eutrophication in Lake Taihu may partly due to the abnormal dry and hotclimate in recent 2 years. However, destroy of submerged macrophytes also possibly contributed to the fast widespread of bloom.

Abstract:This paper presents investigations on geochemical species of phosphorus in sediments and vertical distributions of PO₄^3--Pin interstitial waters of Fubao Bay in Lake Dianchi. The sediments of Fubao Bay had high TP contents, with the maximum value of(5630.59±424.25)mg/kg. I-P(inorganic phosphorus) was the major part of TP, which was about 55%-74% of TP. Fe/Al-P (P bound to Al, Fe and Mn oxides and hydroxides) was the major part of I-P, which was about 90% of I-P. The contents of L-P(labile phosphorus)were very low, which was about 0.5％of TP. The Fe/Al-P contents in sediments were very high, which were highly correlated withhigh eutrophication phenomenon and algae blooming events in Fubao Bay, implying a strong diffusion trend for sediment phosphorusin Fubao Bay. Vertical distributions of sediment phosphorus species were complicated, exhibiting a little disorder in both increasedand decreased trends with the depth. This feature was related to the ecosystem conditions, pollutant discharge and sediment dynamicconditions in Fubao Bay. Peeper technique (in situ dialysis membrane samplers) was used to sample interstitial waters in sediments, andvertical distributions of PO₄^3--P were achieved in the waters. The results showed that concentrations of PO₄^3--P in interstitial waters hadgeneral increases followed by decreases with the depth, reflecting a possible diffusion trend for PO₄^3--P from interstitial waters to overlyingwaters. Regression analyses showed that concentrations of PO₄^3--P in the interstitial waters were positively correlated with L-P contents

Abstract:Changqiao Stream is one of the four upper streams of West Lake. The ecological remediation of Changqiao Streamcreatively integrated sewage disposal technique and landscape garden. Via underground sewage disposal system and artificialwetland, sewage in catchment of Changqiao Stream was disposed physically, chemically and biologically, so as to reduce thepollutant discharge into West Lake. After two years running, the concentration of TP, TN, NH₄⁺-N and COD_Mn were reduced to 0.067±0.041mg/L, 3.54±1.23 mg/L, 0.59±0.46 mg/L and 2.11±0.38 mg/L respectively in 2006, decreasing by 88.5%、 68.8%、 89.1% and 68.0% compared with 2003..

Abstract:The object of research is Chaping River which flows over Anxian County in Mianyang City, Sichuan Province. Based on agreat number of investigations on the load of water pollutants, the situation and function of water environment of the river, theriver-basin hydrological character, the river draining plan, and observation date at environmental monitoring station of MianyangCity Sichuan Province in 2005, two-dimensional hydrodynamic shallow-water model equations were used for monitoring COD and NH₃-N concentrations in section of the Chaping River and the simulations were compared. A one-dimensional model was used tocalculate the water volume capacity of the river's water environments and the ways controlling the total quantity were provided.Results indicated that using two-dimensional hydrodynamic shallow-water model equations to calculate the monitoring sectionshowed a small measured difference for COD and NH₃-N. For the water environmental capacity of Chaping River, COD was 123.96t/a and NH₃-N 42.95 t/a. The COD and NH₃-N emission volume would exceed the capacity in the basin, and the quality of outputwater would exceed the III grades of water protecting standards.

Abstract:By testing a series of solution ³¹P-NMR spectroscopy of model phosphorus compounds including inorganic phosphate,orthophosphate monoesters and diesters, and organic polyphosphate(determined in 1mol/L NaOH and 16.7% D2O), standard phosphorusspectra were obtained as references for solution ³¹P-NMR studies of sediment phosphorus. The results showed that the ³¹P-NMRsignals of phosphorus compounds interested in environmental studies generally fall between 6.5×10^-6 and -25×10^-6, includingorthophosphate at 6.412×10^-6, pyrophosphate at -4.353×10^-6, polyphosphate at -18.159×10^-6 to -20.246×10^-6 (middle group P) and-3.53×10^-6 to -4.40×10^-6 (terminal P), orthophosphate monoesters at 4.3540×10^-6 to 6.3652×10^-6, orthophosphate diesters at-0.107×10^-6 to 2.195×10^-6, and organic polyphosphate at -8.833×10^-6 to 9.499×10^-6 for the α-P. Structure surroundings effect thechemical shifts of phosphorus compounds.

Abstract:Biodegradation of anion-surfactant (LAS) and non-ion surfactant (NIS) in water of Lake Dianchi under the different incubationconditions were studied by the ‘river die-away' method in this paper. The results showed that LAS and NIS could be biodegradated bymicroorganisms in the water of Lake Dianchi. The percentages of degradation of LAS and NIS were more than 95% and 92% after 30days respectively. The biodegradation of LAS and NIS fitted the second kinetic model and the correlation coefficient values were among0.956 to 0.999. Incubation temperature, initial concentrations of surfactants, pH value and nutrients (glucose or Na2HPO4) could affect thebiodegradation of LAS and NIS, Incubation temperature was the major factor influence on biodegradation of surfactant in water of LakeDianchi. When the incubation temperature increased from 20 to 30, the biodegradation rate of LAS increased from 0.73 d^-1 to 2.10d^-1 and the degradation half-life of NIS reduced from 11.5 d to 4.4 d. Increased the initial concentrations of surfactants led to a littleincrease of the degradation half-life of LAS and NIS. The biodegradation of surfactants at pH 7 was slightly easier than that of at pH 10.The degradation of NIS and LAS could be inhibited by added glucose but be promoted by added Na2HPO4. Aeration could accelerate thedegradation of LAS but had limited promotion on the degradation of NIS.

Abstract:Comprehensively sorting out, sifting and analyzing multi-year monthly data of hydrographical, meteorological, water andland uses, social economy, remote sensing from Yanji Basin, this paper simulated and analysed conditions of water-salt balance ofLake Bosten from 1960 to 2003 using Water-Salt Balance Model. Based on these studies, two projects were provided for developmentplanning of Yanji Basin in the near future. And then, it forecasted and analysed water environments of Lake Bosten in future 40 years.According to the simulation results, some conclusion was following: Though there was exporting salt in an accumulation of average306000t/a that made desalination in the lake, it might increase freshwater and decrease input-salt to reduce the degree ofmineralization of Lake Bosten. After the construction projects in recent years were implemented in Yanji Basin, the degree ofmineralization of Dahu would be limited between 0.84g/L and 1.38g/L according to scenarios of Project B. Under such circumstances,the degree of mineralization of Dahu could be adjusted and controlled under 1.00g/L. The degree of mineralization of Dahu coulddecrease to 1.00g/L in 2040 according to the simulation. Water quality of Kongque River was difficult to restore to original state, butits degree of mineralization could be controlled under 0.60g/L because of the improved water environments of Lake Bosten. Forecastanalysis of Project B showed that it was beneficial to water environments of Lake Bosten when the construction project in the nearfuture was completed in Yanji Basin. And water environments of Lake Bosten would tend to a well-ordered circle.

Abstract:High-resolution grain size records from Maogou section in Linxia Basin were characterized with relative stable fluctuationfrom 29Ma and 7.4 Ma, and changes in several sedimentary facies responded to Tibetan uplift in some short intervals. At about 7.4Ma,aeolian dusts gradually entered into Linxia Basin, and input fluxes of aeolian dusts had two rapid increased phases respectively atabout 6.4Ma and 5.3Ma, suggesting that NW China drying climate began at 7.4 Ma and strengthened rapidly at 6.4Ma and 5.3Ma.Comparing of our records with the Tibetan uplift and global climatic records, we found that the gradual uplift of the Tibetan Plateauand global cooling, especially the onset of Arctic ice sheet, since about 9-8 Ma, may be the two important forcing mechanisms for thefast aridification of Asian inland

Abstract:To evaluate the environmental change of Meiliang Bay of Lake Taihu, the elemental geochemical records of the sedimentcore were analyzed by the element enrichment factors and multivariate statistical methods like hierarchical cluster and fuzzy cluster.The results of element enrichment factors showed the enrichment of heavy metals in surface layers. Hierarchical cluster analysismade it possible to separate several groups of elements with different sources or geochemical behaviors. Moreover, fussy C-meansclustering method was applied to divide geochemical records of the sediment into several segments and separate natural factors fromanthropogenic. The enrichment of heavy metals and nutrients above 6cm depth was dominated by human activities. Both lower levelsbetween 25 and 50cm depth and higher levels between 55 and 72cm depth of most elements had been driven by natural processes andbeen affected by catchment sources, and that discrimination between them indicated lacustrine environmental change driven bydifferent natural processes. The transition periods on environment were reflected in other segments. Integrating these multivariatestatistical methods is an efficient tool in achieving better understanding on the quantitative analysis for the complex factors thatinfluence lakes, and helpful to reconstruct the history of environmental change in lakes.

Abstract:The lacustrine sediments deposited between the present water level and the high perched lake shoreline in Lake Jiezechakalocated in the northwestern Tibet provided good records of the lake evolution history. The three U series ages of the lacustrine sedimentsalong the bank are 14.2±1.2kaBP, 38.0±3.5kaBP and 41.6±3.2 kaBP, respectively. The contents of CaO, MgO, NaCl, LiCl and B₂O₃ in sixshallow wells are related to the age and environment when the sediments were deposited. In the end of middle Pleistocene, the lakeshoreline lied in the high perched position probably. From the early period of the Late Pleistocene, the levels of the lake began fallingbecause of the dry climate. The lake shrank gradually and the salinity was increased. Ca and Mg also increased correspondingly. However,around 30kaBP, there was a short wet period when the lacustrine water became less salty. Then, the lake water was further condensed withthe increases in the content of Na, B, and Li significantly. The present salt lake was formed at about 15 kaBP.

Abstract:Sedimentary cores were taken from the center part of Lake Gucheng, Jiangsu in 2005. The total organic carbon, totalnitrogen, phosphorus, metals were analyzed. Calculations of sedimentation rates were achieved using ²¹⁰Pb CRS method. The resultsdemonstrated that average sedimentation was 0.067 cm/a after 1980s corresponding to that from Chernobyl accident marker occurredat 1986. During the period of 1920s and 1980s, the sedimentation rates varied between 0.056 and 0.167cm/a. The high sedimentationrates found in 1960s may be associated with the intense reclamation since 1960s. Cu, Pb, Zn, Cr showed up-core increase in the to p30 cm sediment. Combined with the ratio of these elements to Ti it was concluded that the origin of Cu, Pb, Zn, Cr was not whollyfrom natural processes. The age was between 6500-8000a BC based on AMS ¹⁴C results from depth 0.5 m to 1.78 m, which wascomparable with OSL age of 7-8 ka from the same depth. Sharp transition of index including TOC, TN and metals emerged at depthof 0.3 m may indicate that sediments could be eliminated due to erosion or human impact such as cultivation. It was reported thatLake Gucheng was isolated from Lake Taihu due to establishment of Xiaba at 1556 A.D. Taken the depth of 30 cm as the timewhen Xiaba was established, the average sedimentation rate was calculated to be 0.067cm/a which was in agreement with theresults of ²¹⁰Pb and ¹³⁷Cs method. Therefore, continual deposition may occur after the isolation of Lake Gucheng from LakeTaihu.

Abstract:To evaluate the fish diversity of Yangtze River-connected lakes, a monthly survey of fish assemblage was carried out in theLake Dongting in the middle basin of the Yangtze River in March-December, 2004 and May, 2005. Three sampling areas along atransect from the Yangtze River mainstream to the lake center, i.e. from lake mouth (Chenglinji) to East Lake Dongting (Yueyang)and South Lake Dongting (Yuanjiang) were selected. Totally 69 fish species belonging to 6 orders, 14 families and 44 genera wererecorded. Cyprinids were the richest, accounting for 59.4% of total fish species. Species numbers and diversity indices showed thatfish diversity of the lake was high, with great spatial and temporal variations. Generally, higher diversities occurred in spring andsummer than in autumn and winter, and in South Lake Dongting than in the other areas. With regard to species numbers, the smallerthe distance between sampling area and Yangtze River mainstream was, the earlier the diversity peak was reached. Dominant specieswere determined as species with the value of dominance over 5000. There were 17 dominant species in the lake among which 80.0% were limnicolous species. With regard to ecological groups, limnicolous species dominated the lake, accounting for 74.0% of the totalspecies, while river-lake migratory species was the least, being 13.0% of the total. In comparison with that of 1970s, fish diversity ofLake Dongting had been dramatically decreased, especially for migratory species, and it was mainly due to the loss of habitats, decreasedfry resource and over-fishing. Analysis also showed that fish diversities in Yangtze River-connected lakes were much higher than thoseof disconnected lakes, indicating that river-lake isolation results in species decreasing. Thus, increasing river-lake connectivities isimportant to the conservation of fish diversity in the Yangtze River floodplain.

Abstract:Present/absence method(observed chlorophyll-a content of nature lake phytoplankton with and without addition of Daphnia)wereused to estimate grazing capacity of Daphnia longispina grazing on phytoplankton in Lake Taihu in April, 2006. The results showed thatthe ingesting rate was 0.0011-0.0245μg/(ind·h). There was very nice regression connection between density of D. longispina andingesting rate(R²=0.8836). It was parabola which had maximum value. The ingesting rate of D. longispina and food concentration had alinearity connection(R²=0.8586). The ingesting rate of D. longispina in the present experiments was higher in the dark groups than that ofthe light groups(P<0.05, test).D. longispina grazed most effectively on phytoplankton such as Scenedesmus and Cyclotella, the selectivefeeding indices were 0.5425 and 0.5079. However, D. longispina did not like to eat Ulothrix, the selective feeding index was -0.7039.

Abstract:Viable But Non-Culturable (VBNC) is a special state of bacteria for survival. It is a conventional state for bacteria innatural water body. Complicated environment factors may be the rational reason of the interchange. In this study, the effects ofcyanobacterial media and crude microcystin on the VBNC state of A. sobria were conducted by incubating Aeromonas sobria into asterile lake water. The results showed that some bacteria were in the VBNC state while others in culturable state;both cyanobacterialmedia and crude microcystin could improve the change of A sobria from VBNC state to culturable state. It revealed that microcystinmight be an important environmental factor involved in the VBNC state transfering in aquatic environment. More research concernedabout molecular mechanism was undergoing.

Abstract:On August 2006, grave soils from organic and conventional farming were sampled within the watershed of Fuxian Lake inYunnan Province. Soil granule composition, heavy metal contents and nutrition accumulation in the soil profile were determined.Nitrogen and phosphorus losses from the soils were assessed by the in-door rainfall simulation. The results were as below: 1) bothorganic and conventional farming practices significantly lower the soil sand content on the 0-20 cm soil profile;2) all soil heavymetal contents met the Class A standard of National Environment Quality Standard for Soils (GB/15618-1995) except Cd which onlymet Class B standard;3) soil total nitrogen and organic matter accumulated in the 0-20 cm soil profile, and showed no significantdifferences between organic and conventional farming practices. The accumulation of soil total phosphorus, NO3-N and waterdissolved phosphorus (WSP) under the organic farming practice is significantly higher than those under conventional farmingpractice;and 4) under the condition of 780 mm rainfall simulation, the risk of nitrogen and phosphorus losses from the organicfarming soil is higher than that from the conventional farming. Total amount of nitrogen and phosphorus losses from the organicfarming soil were 1.9 and 19.8 times higher than those from the conventional farming soil, respectively.

Abstract:On the basis of measured data about wave in Lake Taihu, the calibrated wave model which was described by thethird-generation spectral action balance equation was obtained. The several key wave's factors were considered in SWAN model suchas bottom topography, wave refraction, depth-induced dissipation, wave break, lake current, etc. The wave in Lake Taihu wassimulated and the main influence factors of wave were analyzed by this model. The results showed that the SWAN model can welldescribe the process of wave's growth and propagation in Lake Taihu. The distribution of wave heights, wave lengths, wave periods,etc, were closely related to wind speed, wind direction, water depth, etc. On the condition of the same direction and different windspeed, the required time from wave growth to wave stabilization was different;However, On the condition of the different directionand same wind speed, the required time was nearly the same. Therefore wave's growth were not only depended on wind speed, butalso depended on the wind's sustained action and fetch.

Abstract:Based on daily precipitation data of 147 stations in the Yangtze River Basin during the flood season (April to September)for 1960-2005, extreme high precipitation (percentile >95th) and its time gap, days with precipitation <1.27mm/d and its durationwere calculated. Accordingly, spatial distributions and temporal sequences of extreme precipitation events had been analyzed, and theprobability model was established. Research results showed that Sichuan Basin in the upper reaches and southeastern Lake PoyangCatchment in the mid-lower reaches were the high precipitation center of the Yangtze River Basin with centralized extreme event.Total number of days with precipitation <1.27mm/d is more in the mainstream section, Minjiang-Tuojiang Catchment and upperWujiang Catchment than any other area of the Yangtze River Basin. However, due to shorter lasting period of events with < 1.27mm/d,it did not create serious drought situation in theses areas. Whereas, areas in the upper and lower Jinshajiang(upper reaches of theYangtze River) Catchment, Lake Dongting Catchment, southeastern Lake Poyang Catchment, and lower main stream section, weremore likely to be stricken by prolonged events with <1.27mm/d and droughts caused. By applying Weibull model with the method ofmaximum likelihood estimator on the time gap of extreme high precipitation and lasting period of <1.27mm/d, it was proved thatWeibull-Ⅱ can simulate well the probability distribution of timing of extreme precipitation events over the Yangtze River Basin.Changes of Weibull-Ⅱ parameter can reflect well the spatial and temporal variation of timing of extreme precipitation events.

Abstract:Based on the relationship between regional development and water environment protect and affection of water environmentquality of river and lake on regional development, the paper analysed regional disparity of water environmental risk and controllingof water pollution discharge in regional development. Taking Wuxi as a case, comprehensively considering physical geographicalfactors such as river and lake hydrological condition, watershed geomorphic condition etc, the whole city had been divided into twosections of the first grade environmental cells, thirty four sections of the second grade environment sub-cells, as estimating cells ofwater environmental risk. According to the relationships between land development and change of water environments, severalfactors had been selected, such as function of water utilization, connecting condition to water body (Lake Taihu, Yangtze River, etc)outside, water quality needs and the channels of leading water, and geomorphic condition for evaluating and regionalize the risk ofwater environments for four grads by using GIS spatial analyzing and statistic analyzing methods. As a result, the area with big riskof water environments would not allow the development of water polluting factory and inhabitant quarter. It could be the one ofguidances for the spatial development.

Abstract:The water areas of Lake Qinghai in the past twenty years have been identified using NOAA/AVHRR satellite data. Theresults show that the area of Lake Qinghai has been decreased in these years, and the area of decreasing is mainly in the north of LakeQinghai. To find out the climate elements which affect the area of Lake Qinghai, precipitation, temperature and evaporation in theregion of Lake Qinghai are analyzed. The results show that increasing in temperature and evaporation, and the decreasing inprecipitation are the main reasons for the decreasing in the area of Lake Qinghai.