Abstract:The levee project around Taihu Lake is one of the ten key projects of comprehensive management in Taihu Basin. The principles of planning and designing of the project are presented. Also the function of multi-purpose development of comprehensive management in Taihu Basin is described.

Abstract:The factor which influences floods of river reaches on lakeshore plain is very complicated and the stage-discharge relation varies greatly. It is very difficult to forcast the water level in this area-This paper proposes a water level forcasting method suitable to the river reaches on lakeshore plain, on the basis of the characteristics of the floods. It is comfirmed to be one reasonable method through the case study.

Abstract:Lake survey shows that Hanas Lake, with maximun water depth of 188. 5m, mean water depth of 120.1m and excellent fresh water capacity of 5.378km³, is one of very prominent lakes in China. The cross section of the lake bottom shows an unusual chest-like form and the lake faults are still in intensive action now. The grain size distribution is controlled chiefly by longitudinal transportation, and influnced by traverse transportation in the local area with quite low concentration of the most nutrient elements in the sediments. Minerals and chemical elements of the sediments are obviously under the control of sedimentary environments, with quite low concentration of the most elements in the sediments. Its sedimentary rate is measured 0.52mm/a by ²¹⁰Pb,but insufficient to compensate the lake faulting,as a result,the lake depth will get increased even more.

Abstract:Lakes in the plain and desert area in Xinjiang autonomous region have been shrinking greatly due to irrigation since the 1950s,and some lakes have even dried up,resulting in such environmental effects as land desertization, fauna-flora degradation, fish-yield reduction and the local climate changes. Since these effects were overestimated and the main causes to arise effects mentioned above were confused, further discussion is made on these effects comprehensively.

Abstract:Sheyang Lake was a famous large lake in North Jiangsu in historical period. During the early Holocene, it was transgressed and reduced into a part of Lixahe bay. During the middle Holocene, an old lagoon was formed as the result of the formation of offshores. Later,due to eastward movement of the coastline and flushing action of freshwater, the old lagoon turned into a freshwater lake gradually. As the Yellow River captured the Huaihe River in 1128, a great quantity of sand was carried into the lake and piled up there swiftly. A lot of marshlands were formed in the lake. In addition to man's remarkable influence, it became a part of the Lixiahe Plain.

Abstract:According to the field observation and the results of chemical analysis,this paper deals with the hydrochemical character of the Aibi Lake water from the following three aspects; (1) Salinity and pH value of the lake water, (2)Chemical composition of the lake water, and (3) The latteral distribution of chemical components in the lake water which reveal laws of hydrochemical changes and the migration and accumulation of main elements in the lake water. The carbonate minerals compositions in the lake sediments and their geochemical nature reflect the variation of the chemical composition in the lake water. This case is obvionsly influenced by the climate environment. Thereby, the carbonate sediments in the drilling hole CK4 and recorded information from the lake bottom may be as the indicators df chemical evolution of the lake water and the paleoclimate variation. According to the content of carbonate,the content of calcite,MgC0₃ in calcite crystal skeleton,the content of Sr, Sr X 1000/Ca ratio and so on, as combined with sedimental character, geochemical evolution of carbonate and evolution of palaeosandspit, the trend in chemical evolution of lake water has been illustrated further. On the basis of the above mentioned,the chemical evolution of lake water can be divided into three stages:J. The first stage(45000-23000 a B.P.):the lake water underwent two fluctuations and caused two lower levels with its carbonate mainly consisting of calcite. This stage belongs to fresh water deposition; 2. The second stage(23000-12000 a B.P.): the lake water level was higher than that of the first stage,the salinity of lake water is lower than that, the content of calcite appeared to decrease with MgC0₃ in calcite crystal skeleton equal to zero; 3. The third stage (12000 a B. P. to present): the lake water level was the lowest. Some aragonite was separated out from the lake water, gradually being at its dominant position,and exceeded calcite in content.

Abstract:Experiments in intensive fish culture have been conducted in both Waguo Reservoir of 8.9 hm² and Shishantou Reservoir of 17.3 hmz in Jiangsu Province since 1984. This technique involves: reforming of traditional way to culture fish adopting various stocking models of mixed species and of high stocking density, improving food basis by increasing artificial feeding, shortening fish culture period by increasing stocking size, self-sufficiency in fish fingerling production by various nursing methods such as caves in reservoir and ponds, adopting of cage culture, interval fish catching with cage weirs, paying special attention to ecological fish culture by rearing poultry and livestock as well as greenfeed.With the results of application of the new technique, the fish yield of Waguo Reservoir increased from 195 kg/hm² in 1983 to 4176 kg/hm² in 1986, that of Shishantou Reservoir increased from 86 kg/hm² in 1984 to 7822 kg/hm² in 1989, an economic benefit of RMB 10140 per hm². This technique has already been applied in 51 small reservoirs in Jiangsu Province.

Abstract:Seasonal changes of number and biomass of zooperiphyton on suspended substrates in' Xuanwu Lake were studied. The main species are Epistylis plvcatdis,VoHicella convallaria, V orlicella campanula, Brachionus urceus and Brachionus cap suliflous. The number and the biomass of perihytic protozoan are large in summer and fall with their maximum number being 19952 ind. /cm² and the maximum biomass 296.6/ig/cm² in Station I, and with maximum number being 16393 ind. /cm² and the maximum biomass 246.5pg/cm² in Station II. The number of periphytic rotifera is large in fall and winter,with their maximum number being 873 ind. /cm² and the maximum biomass 958.3 ng/cm² in Station I in October and with their maximum number being 201 ind. /cm² and the maximum biomass 257 p.g/cm² in Station II in February. The yearly mean number for zooperiphyton is 4661 ind. /cm² and the yearly mean biomass is 391 /ig/cm² in Station I. The yearly mean biomass is 3037 ind. /cm² and the yearly mean biomass is 150.6jxg/cm² in Station II. So both the number and the biomass are larger in Station I than in Station II. According to indicative organism, the eutrophication has been very serious in Xuanwu Lake.

Abstract:According to “the protective mothed of water pollution” an emission licence system of water pollutant, and lake water pollution situation, the technical principle, work programme and calculated methods of water pollutant emission standards were put forward with some calculated samples in different typical lakes for the use of local lake management departments in making the local water pollutant emission standards.

Abstract:The trophic levels of 19 reservoirs have been classified by using Q-matrix in cluster analysis and its comparison with fuzzy cluster analysis has also been made, and a new 0-1 higher index discrimination for the trophic level classification of one reservoir has been established. All methods are transferred into computer programmes and the impending problems of the trophic level classification are put forward.

Abstract:According to the recent research literatures on saline lakes, the conception of saline lake, geographical distribution and lake basin origin is introduced. The physical research realms of saline lake are illustrated from both optical properties (transparency, colour, turbidity, attenuation) and thermal characteristics, contemporaneously, the chemical features of saline lakes are mentioned from salinity, evaporation and salinity, salt sources,chemical composition and types of saline water and evolution of saline lakes. From the viewpoint of relationship between salty deposits and paleoclimate, it is evident that the paleolimnological studies of saline lakes show a great potantiality for reconstructing the history of past global change, an important part in global research system.