Abstract:Correlation fractal analysis and R/S analysis of four indexes from Core TS95, Tianshuihai Lake, western Tibetan Plateau, FeO, Fe₂O₃, the rat io of Fe₂O₃/FeO, and organic carbon, are conducted.It is found obviously that the 4 time series are chaotic and have Hurst phenomena. The chaotic or abnormal att ractors for FeO, Fe₂O₃, Fe₂O₃/FeO and organic carbon are 2.8, 3. 2, 2.9 and 2.5 respectively wi th saturated embedded dimensions ranging from 5 to 6, suggesting that the dynamic system cont rolling the local climatic and environmental evolution is chao tic.It has definte variables.To establish the system, at least 3 to 4 variables, at most 5-6 variables, are needed.This generally ag rees wi th deep-sea oxygen isotope and differs by large from some climatic indexes of loess profiles.The Hurst indexes of the four pro xies are FeO-0.85, Fe₂O₃-0.76, Fe₂O₃/FeO-0.65 and organic carbon-0.74 respectively, indicating that they have obviously longrun dependence-persistence.This is in acco rdance with previous studies^[13-15].The persistence results most probably from the uplift of Tibetan Plateau.This suggests that in addition to the global vacillation of climate and environment, some local factors such as the uplift of Tibetan Plateau and the change in Tianshuihai Lake drain age, have probably played a role on the pro xies of climate and environment.The differences between the four Hurst indexes result possibly from the relat ively easy mig ration of FeO that is influenced by the hydrological change of the drainage. The organic carbon and Fe₂O₃, the two of the four, are probably more sui table to ext ract the persistence component of environmental evolution.

Abstract:The Dabusu Lake, located in the Songnen (Songhuajiang River-Nenjiang River) Plain, northeastern China, is a closed tectonic fault lake.The investigation on the geomo rphology and depositional ty pes of the basin revealed that the evolution process of the Dabusu Lake was signif icant for interpreting regional envi ronmental evolution. On the basis of the investigat ion as well as ¹⁴C dating, we concluded that the Dabusu Lake was formed in late-Pleistocene.In early times of lake evolution, the Dabusu Lake was a deep lake.Since Holocene, the lake level fluctuated with two enlarging periods and two shrinking preiods, showing that the lake has undertaken two complete deposit ional cycles of lake advance and ret reat.Since mid-Holocene, due to the dryer climate and stronger wind force, the lake level dropped and lake shrank.From then on, the lake gradually turned into a salty lake, which was rare in Northeastern China.

Abstract:In this paper, many historical documents and local chronicles were analyzed to investigate the effects of human activities on evolut ions of Sheyang Lake, the results show ed that during the period from the Qin-Han Dy nasty to South Song Dynasty, the Fan'gong dike and the canals heavily affected the evolution of Shey ang Lake from lagoon to freshw ater lake, especially the Fan' gong dike.However, there were a few times of the canal dike bursting, resulting some silt brought by the river in the lake region that it did not heavily af fect the Sheyang Lake.Similarly, Reclaimation from lakes was minor, therefore the area of Sheyang Lake remained unchanged. In the past 700 years or so, the Huang he River Rad had captured Huaihe River for many times, especially after Jia-Long of the Ming Dynasty, the Sheyang Lake reduced extensively because it received a great quantity of silt which was brought in by Huang he River.As a result of the dike-const ruction of the canal and lakes, Sheyang Lake had frequent flood disasters which resulted in the acceleration of siltation.Channel dredging and reclamation around the lake made Sheyang Lake shrunk, disintegrated, and turned into a long strip one, most of which became marsh or farmland by the end of the Qing Dynasty.

Abstract:This paper deals with the use of correspondence analysis as an aid in paleoclimatic reco nst ruction based on modern and fossil pollen data.Modern pollen data from surface samples, ref lecting present vegetation ty pes across the eastern part of China, w ere used to set up pollen-climate transfer functions.The transfer functions were then applied to pollen-stratigraphic data from dated sediment core of Qingpu County of Shanghai to reconstruct the paleoclimate of Shang hai since 8.5 ka B.P..Result shows that since 8.5 ka B.P.the mean temperature and the precipitation had been increasing, betw een approximately 8.2-6.0 ka B.P., the paleoclimate becoming warmer and humid with high fluctuation, the maximum values of temperature and precipitation were 18.5℃ and 1575mm respectively;from 6.0 ka B.P.to 4.0 ka B.P., the climate was cool and dry, with the minimum value 13.5℃ and 827mm;during 4.0-2.0 ka B.P., it became warm and more humid;follow ed by tendency of cool and drier.The paleoclimatic change played an important role in the development of Neolithic culture in this area.

Abstract:The system of evaluating losses of flood disaster is one of important components of flood-proof decision-making system in Taihu Lake catchment and it can accurately forecast and evaluate the flood disaster in Taihu Lake catchment at the same time provide scientific foundation to flood-proof.This paper from GIS application & developmental point of view introduces the technique systems of GIS software, the frame of technology, the characteristic and effect of spatial database as well as main functions of the system.

Abstract:It has been measured that the pH value and concentrations of nutrients such as N and P etc. in the rain and runoff at the mouth of Meiliang Bay, Lake Taihu from January 1998 to June 2000. Due to the affection of rainfall, the TIN, PO₄^3- and CODMn are amounts to 10-15%, 2.0% and 4-6% of the total pollutes loads that was enter to the lake in the same period respectively. It was measured also that the total hard ions and alkalinity concentrations at the mouth of Meiliang Bay, Lake Taihu, in the March-June of 1999. According to the analysis with historic dada it has been found that the ratio of total hard ions over to the alkalinity in water of lake was raised with time. This phenomenon could reflect the response of aquatic ecosystem, Lake Taihu, to the deposition of acid rainfall in long term.

Abstract:The annual fluctuation of chlo rophyll-a concent rations and some chemical indicators were measured in the main areas of West Lake, Hangzhou during January-December 1999.The algal grow th potential test in water from West Lake were made.The relations between the chlo rophylla concent rations and various ecolog ical factors were discussed.The experimental results are as follows.The concent rations of chlorophyll-a in main Lake-areas appear in the same level.The range was 41.16-191.26mg/m³ and the annual average concent ration was 99.98mg/m³.The concentrations of chlo rophyll-a showed marked seasonal variation the highest in summer and early autumn and the low est in winter.The concent ration of chlorophyll-a has close relation with water temperature and TP.The West Lake is a typical Cyanophyta-pat tern lake in which the annual average concent rations of TN and TP were 2.08mg/L and 0.121mg/L respect ively.The ratio of TN to TP is more than 17 in West Lake, indicating TP's domination in the stimulation of algal growth.

Abstract:This paper presents a modified ecological model of algae growth in Taihu Lake and its novel numerical algorithm. In this model, many important factors, such as the water temperature total nitrogen total phosphor, the biomass of the zooplankton radiation etc., are taken into account for the growth rate of the algae. Moreover, the mortality rate of the algae is considered and modified according to the value of water temperature total phosphorus and the biomass of the algae.As a result, a more accurate description of the behavior of the algae is obtained. The performance of stability and accuracy is very important for the correct simulation procedure. A numerical algorithm that has the property of absolute stability and second-order accuracy is proposed and is used to solve the partial differentialequations in the ecological model. In order to perform a further validation of the modeL the field-measured data in Taihu Lake in 1998 are adopted in the simulation, Because only one set of the field-measured data per month i. e., total twelve sets of data are available estimated data of every day are required to perform the simulation correctly, In this paper the estimated data of the water temperature total nitrogen the biomass of the zooplankton and radiation are obtained by interpolation method, In the ecological model there is a direct coupling between the algae and totalphosphorus; therefore the estimated data of phosphorus can not be obtained by simple interpolation, A generalized fitting method is then developed to solve this problem. With this method, the characteristic of the totalphosphorus obeys the ecological model, Meanwhile the values of the simulated total phosphorus are approached to the field-measured data optimally. Basically, the simulated results fairly agree with the field-measured results.Explanations are given to some distinct differences between the simulated results and field-measured results, It is demonstrated that the ecological model and the algorithm are reliable and efficient for the simulation of the actual ecological behavior of algae.

Abstract:A st rain of Chlorella ellipsoidea with high tolerance to heavy metals was isolated. Grow th and heavy metals removal were studied on this alg a exposed to different heavy metal concent rations.The ef fect of heavy metal on grow th indicated that cells can live in higher Zn²⁺ and Cd²⁺ concent rations.The tolerant sequence to 4 kinds of metals for C.ell ipsoidea was Zn²⁺ > Cd²⁺ > Ni²⁺ > Cu²⁺.The content of chlo rophyll a decreased with the increase of heavy metal concent rations. In this ex periment, C.ellipsoidea also show ed its rather st rong ability to remove heavy metals from the medium.After 72-hour treatment, the removal rates of metals were 40.93%, 98.33%, 97.62%and 86.88% respectively, for 15 μmol/L Cu²⁺, 300μmol/L Zn²⁺, 100μmol/L Ni²⁺ and 30μmol/L Cd²⁺.These results suggested that the C.ellipsoidea strain could be applied to the treatment of heavy metal wastewater.

Abstract:The toxic effect of various concentrations of Hg²⁺ on the photosythentic O₂ evolution respiration rate the permeability of cell membrane nitrate reductase activity and the ultrastructure changes in leaf cells of Hydrocharis dubia were studied. The results showed that the photosythentic O₂ evolution decreased respiration rate and nitrate reductase activity first increased and then decreased while the permeability of cell membrane was increased. Lltrastructure observation revealed that the chromatin condensed the thylakoids of chloroplast and cristae of mitochondria swelled at the early stage when the leaves suffered the poison of Hg²⁺. With the increasing of the poison nuclear membrane disrupted the chromatin and nucleoplasm disappeared, chloroplast disintegrated and mitochondria vesiculated.

Abstract:This paper mainly deals with the changes of external morphology, the activity of peroxidase and nit rate reductase, the content of chlorophyll, O₂^-· and MDA in Brasenia schreberi by Cr⁶⁺ treatment.The results show ed the reason of Cr⁶⁺ injuring Brasenia schreberi w as that Cr⁶⁺ inhibited the activity of enzymes and damaged membrane.In the third day, the content of chlorophyll reduced with the increasing concent ration of Cr⁶⁺, the activity of peroxidase was the highest at 10 mg/L, the activity of nit rate reductase was a lit tle higher at 5mg/L, but reduced with the increasing concent ration of Cr⁶⁺ up to 40mg/L, the content of O₂^-· w as the highest at 5mg/L, and a little higher than control group at 10mg/L, then it reduced with the increasing culture concentration of Cr⁶⁺, the trend of changes in MDA was relatively similar with that of O₂^-·.

Abstract:Based on lake's main envi ronmental problems such as eut rophication, soil and water loss and the lack of water resource, series of projects for comprehensive pollution treatment for the whole Xinyun Lake catchments, Yunnan Province are put forw ard, which focuses on N, P and eutrophication cont rol.There are 11 projects in total, including treatment of industrial pollution source, treatment of domestic sewage, treatment of agriculture non point pollution, and restoration of lake ecosy stem, etc.Total investment for these project is expected to be about 464 million Yuan RMB.

Abstract:The fish productivity of Daihai Lake is low due to the poor species richness and low biomass of aquatic communities. The biomass and structure of biological structure evolution aswell as the impacts on the fishery development are analysed.For the sustainable development of fisheries in Daihai Lake some suggestions are put forward, i. e., introducing low-temperature-proof, salinity-proof aquatic plants and algae, regulating fish community structure improving environment quality for habitation and so on.

Abstract:Erhai Lake known as a "bright pearl" on Yunnan Plateau the second largest plateau lake in Yunnan is located in the central part of Dali prefecture. In 1996 blue agal bloom was first observed in Erhai Lake which showed that Erhai Lake had undergone overwhelming eutrophication.The possible causes of eutrophication in Erhai Lake were analysed in detail. Investigations revealed that the blue algal bloom was on the mid-trophic status indicating that nutrient accumulation was not the only factor. Some environmental and biological changes were observed especially in 1990s due much to the human activities interruption. Finally, some countermeasures for eutrophication control are put forward.