Water Body Extraction Research Based on S Band SAR Satellite of HJ-1-C

The problem of Lake Nieuwe Meer (area = 1.3 km2, max. depth 30 m, Ptot = 500 mg/m3) was extensive growth of Microcystis with disturbing scum forming. Since 1993 the lake has been artificially mixed in summer by a bubble plume installation. The result is quite successful since the mass of Microcystis is up to 20 times lower than in the years before mixing and no scum is present any more. The study in Lake Nieuwe Meer showed a shift from cyanobacterial dominance (mainly Microcystis) to flagellates, green-algae and diatoms when artificial mixing was applied. Total phosphorus and nitrogen concentrations did not change as a result of mixing and had apparently no effect on the shift in the phytoplankton composition. The chlorophyll-a concentration was much lower in the mixed lake as a result of dilution. The total algae biomass decreased. The transparency did not improve. The total heat energy of the lake is slightly higher than before mixing but still remains in the range of annual fluctuation. The temperature on the surface is approximately 2°C lower. In the whole water-body oxygen was always higher than 5 mg/l. Living space for fish is therefore wider. The installation in Lake Nieuwe Meer consists of flexible pipes near the sediment, built in a way to prevent sediment erosion and transport into the water. There are no constructions in the water-body. All mechanical parts are on land. The layout of the installation is shown in Fig. 1. Installed compressor energy is 85 kW. This is equivalent to an upper middle-class motor-car. The design was made specifically for this problem. It is based on the physical data of the algae and the plant. It would be beneficial to use this 7 year's experience for further applications e.g. elimination of toxic algae in drinking-water reservoirs.

Download Full-text

Development of Dialog System Model for Eutrophication Control between Discharging River Basin and Receiving Water Body – Case Study of Lake Sagami (Japan)

Water Science & Technology ◽

10.2166/wst.1989.0178 ◽

1989 ◽

Vol 21 (12) ◽

pp. 1821-1824

Author(s):

M. Suzuki ◽

K. Chihara ◽

M. Okada ◽

H. Kawashima ◽

S. Hoshino

Keyword(s):

Water Management ◽

Water Quality ◽

Expert System ◽

River Basin ◽

Water Body ◽

Water Bodies ◽

Quality Data ◽

Pollution Load ◽

Water Quality Data ◽

Receiving Water

A computer program based on expert system software was developed and proposed as a prototype model for water management to control eutrophication problems in receiving water bodies (Suzuki etal., 1988). The system has several expert functions: 1. data input and estimation of pollution load generated and discharged in the river watershed; 2. estimation of pollution load run-off entering rivers; 3. estimation of water quality of receiving water bodies, such as lakes; and 4. assisting man-machine dialog operation. The program can be used with MS-DOS BASIC and assembler in a 16 bit personal computer. Five spread sheets are utilized in calculation and summation of the pollutant load, using multi-windows. Partial differential equations for an ecological model for simulation of self-purification in shallow rivers and simulation of seasonal variations of water quality in a lake were converted to computer programs and included in the expert system. The simulated results of water quality are shown on the monitor graphically. In this study, the expert system thus developed was used to estimate the present state of one typical polluted river basin. The river was the Katsura, which flows into Lake Sagami, a lake dammed for water supply. Data which had been actually measured were compared with the simulated water quality data, and good agreement was found. This type of expert system is expected to be useful for water management of a closed water body.

Download Full-text

Assessment of Turbulent Processes in Lake Kinneret by the Two-Dimensional Reservoir Water Quality Model “Better”

Water Science & Technology ◽

10.2166/wst.1993.0573 ◽

1993 ◽

Vol 27 (7-8) ◽

pp. 381-385 ◽

Cited By ~ 1

Author(s):

Y. Oziransky ◽

B. Shteinman

Keyword(s):

Water Body ◽

River Mouth ◽

Temporal Distribution ◽

Lake Kinneret ◽

Toxic Substances ◽

Two Dimensional ◽

Quality Model ◽

Reservoir Water ◽

The North ◽

Longitudinal Gradients

Data of high spatial and temporal resolution, and a special sampling program are essential for successful application of mathematical models designed to reproduce observed seasonal patterns of temperature, dissolved oxygen, nutrients, pH, and algal biomass for both vertical and longitudinal gradients in a water body. Lake Kinneret suspended solids are of great potential value for estimating transport, exposure to water body elements, and fate of many toxic substances. Therefore the distribution of admixtures in two longitudinal and five vertical segmentation schemes were examined with the two-dimensional water body quality box model “BETTER” (Bender et al, 1990). The transects were taken in the north-western part of Lake Kinneret close to the Jordan River mouth and the National Water Carrier (NWC) head pumping station. The outflow volumes were given according to regular sampling of natural speed of water outflow from different lake layers under calm conditions. Temporal distribution of mixing concentrations as well as turbulent diffusion horizontal coefficients due to the spatial distribution of turbulent scale were obtained during the model's run with the December 1991 data.

Download Full-text

AMEBAS PATÓGENAS DE VIDA LIBRE DEL GÉNERO ACANTHAMOEBA EN AGUAS RECREATIVAS EN LA HUASTECA POTOSINA, MÉXICO

BIOCYT Biología Ciencia y Tecnología ◽

10.22201/fesi.20072082.2014.7.76134 ◽

2014 ◽

Vol 7 ◽

Author(s):

Ricardo Ortiz Ortega ◽

Alonso Vilches Flores ◽

Marco Aurelio Rodríguez Monroy ◽

Patricia Bonilla Lemus

Keyword(s):

High Temperature ◽

Water Body ◽

Tropical Climate ◽

Dry Season ◽

Thermal Waters ◽

Free Living ◽

Severe Infections ◽

Amebic Encephalitis ◽

Animal Tests

Studies accomplished in freshwater demonstrate the importance of identify the presence of protozoa like free living amoebae (FLA). In particular, the genera Acanthamoeba is associated with severe infections in man, as the Granulomatous Amebic Encephalitis (GAE). The most important factor for the development of these organisms is the high temperature of the water body. The region of the Huasteca Potosina in Mexico, with a tropical climate and great aquatic resorts, like rivers, waterfalls and pools of thermal waters, that allows the development of amoebae. In this study we evaluated the presence of amoebas in the most visited places on the Huasteca Potosina. Samples of a liter were taken in nine sites during the rainy and dry season. 54 strains of amoebas were identify, 46 belong to the genera Acanthamoeba, resulting 30 of them pathogenic in the animal tests. The pathogenic isolated amoebas were present in the most attended resorts by the people in the waterfalls or pools of the places sampling. Temperature turned out to be the most important factor for the presence of amoebae.

Download Full-text

Spatial-Temporal Change of Land Use and Its Impact on Water Quality of East-Liao River Basin from 2000 to 2020

Water ◽

10.3390/w13141955 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1955

Author(s):

Mingxi Zhang ◽

Guangzhi Rong ◽

Aru Han ◽

Dao Riao ◽

Xingpeng Liu ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

Land Use Change ◽

Point Source ◽

Water Body ◽

Forest Land ◽

Point Source Pollution ◽

Construction Land ◽

Unused Land ◽

Non Point Source Pollution

Land use change is an important driving force factor affecting the river water environment and directly affecting water quality. To analyze the impact of land use change on water quality change, this study first analyzed the land use change index of the study area. Then, the study area was divided into three subzones based on surface runoff. The relationship between the characteristics of land use change and the water quality grade was obtained by grey correlation analysis. The results showed that the land use types changed significantly in the study area since 2000, and water body and forest land were the two land types with the most significant changes. The transfer rate is cultivated field > forest land > construction land > grassland > unused land > water body. The entropy value of land use information is represented as Area I > Area III > Area II. The shift range of gravity center is forest land > grassland > water body > unused land > construction land > cultivated field. There is a strong correlation between land use change index and water quality, which can be improved and managed by changing the land use type. It is necessary to establish ecological protection areas or functional areas in Area I, artificial lawns or plantations shall be built in the river around the water body to intercept pollutants from non-point source pollution in Area II, and scientific and rational farming in the lower reaches of rivers can reduce non-point source pollution caused by farming.

Download Full-text