scholarly journals Analysis Of Reed Resource Dynamics In Water Bodies Of Eastern Latvia

Author(s):  
E. Čubars ◽  
G. Noviks

The paper shows the results obtained during the research of reed dynamics revealing that in Eastern Latvia 20 lakes and pisciculture farms are potentially important for the reed extraction. In 2008, the reed resources there covered a territory of approximately 2300 ha. The ortophoto images of potentially important water bodies made in 1997, 2005 and 2008 were analyzed using the computer program ArcMap. The reed growth develops differently in every water body, but in general the eutrophication of water bodies and the enlargement of reed-covered areas can be observed. The most rapidly the reed occupies new territories in pisciculture farms and shallow lakes. The analysis of reed resource dynamics show that reed-covered areas in this region are expanding every year. The main factors that influence the distribution of reed growths refer to human activities, climatic conditions, hydrological regime in water bodies and natural processes of eutrophication.

2022 ◽  
Vol 14 (1) ◽  
pp. 200
Author(s):  
Lingjun Wang ◽  
Wanjuan Bie ◽  
Haocheng Li ◽  
Tanghong Liao ◽  
Xingxing Ding ◽  
...  

Small water bodies ranging in size from 1 to 50,000 m2, are numerous, widely distributed, and have various functions in water storage, agriculture, and fisheries. Small water bodies used for agriculture and fisheries are economically significant in China, hence it is important to properly identify and analyze them. In remote sensing technology, water body identification based on band analysis, image classification, and water indices are often designed for large, homogenous water bodies. Traditional water indices are often less accurate for small water bodies, which often contain submerged or floating plants or easily confused with hill shade. Water quality inversion commonly depends on establishing the relationship between the concentration of water constituents and the observed spectral reflectance. However, individual variation in water quality in small water bodies is enormous and often far beyond the range of existing water quality inversion models. In this study, we propose a method for small water body identification and water quality estimation and test its applicability in Wuhan. The kappa coefficient of small water body identification is over 0.95, and the coefficient of determination of the water quality inversion model is over 0.9. Our results show that the method proposed in this study can be employed to accurately monitor the dynamics of small water bodies. Due to the outbreak of the COVID-19 pandemic, the intensity of human activities decreased. As a response, significant changes in the water quality of small water bodies were observed. The results also suggest that the water quality of small water bodies under different production modes (intensive/casual) respond differently in spatial and temporal dimensions to the decrease in human activities. These results illustrate that effective remote sensing monitoring of small water bodies can provide valuable information on water quality.


2019 ◽  
pp. 257-266
Author(s):  
A.I. Shishkin ◽  
L.A. Mosur

In the paper is used the systems approach to justification and optimization ofnorms of the load on the transboundary water bodies. Special attention was given to evaluation of the factors determining the norms of load on the natural water systems for individualtransboundary water bodies. The effects of the pollutant transformation in the water bodiesare taken into account. The algorithm of attribution of quotas to various kinds of man-causedload along entire length of the water body in question is offered. The concrete methods ofmeeting the environmental norms for the priority-driven types of pollutants. It is offered tointroduce the norms attribution basing on environmental and emission approaches and takinginto account the use of the best technologies for industrial and natural systems.


2018 ◽  
Author(s):  
S.V. Maltsev

Отражены результаты исследования основных факторов (сорт, почвенно-климатические условия выращивания, фон минерального питания, температура хранения сырья и готового продукта, срок переработки), определяющих пригодность картофеля к вакуумной упаковке и быстрой заморозке без применения консервантов.The article reveals main factors (such as potato variety, soil and climatic conditions, doses of mineral fertilizers, store temperatures, different timelines of processing) determining the suitability of potatoes for vacuum packaging and fast freezing without usage of chemicals.


1989 ◽  
Vol 21 (12) ◽  
pp. 1821-1824
Author(s):  
M. Suzuki ◽  
K. Chihara ◽  
M. Okada ◽  
H. Kawashima ◽  
S. Hoshino

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.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Hendri Irwandi ◽  
Mohammad Syamsu Rosid ◽  
Terry Mart

AbstractThis research quantitatively and qualitatively analyzes the factors responsible for the water level variations in Lake Toba, North Sumatra Province, Indonesia. According to several studies carried out from 1993 to 2020, changes in the water level were associated with climate variability, climate change, and human activities. Furthermore, these studies stated that reduced rainfall during the rainy season due to the El Niño Southern Oscillation (ENSO) and the continuous increase in the maximum and average temperatures were some of the effects of climate change in the Lake Toba catchment area. Additionally, human interventions such as industrial activities, population growth, and damage to the surrounding environment of the Lake Toba watershed had significant impacts in terms of decreasing the water level. However, these studies were unable to determine the factor that had the most significant effect, although studies on other lakes worldwide have shown these factors are the main causes of fluctuations or decreases in water levels. A simulation study of Lake Toba's water balance showed the possibility of having a water surplus until the mid-twenty-first century. The input discharge was predicted to be greater than the output; therefore, Lake Toba could be optimized without affecting the future water level. However, the climate projections depicted a different situation, with scenarios predicting the possibility of extreme climate anomalies, demonstrating drier climatic conditions in the future. This review concludes that it is necessary to conduct an in-depth, comprehensive, and systematic study to identify the most dominant factor among the three that is causing the decrease in the Lake Toba water level and to describe the future projected water level.


2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Xianghong Che ◽  
Min Feng ◽  
Hao Jiang ◽  
Jia Song ◽  
Bei Jia

Inland surface water is essential to terrestrial ecosystems and human civilization. Accurate mapping of surface water dynamic is vital for both scientific research and policy-driven applications. MODIS provides twice observation per day, making it perfect for monitoring temporal water dynamic. Although MODIS provides two bands at 250 m resolution, accurately deriving water area always depends on observations from the spectral bands with 500 m resolution, which limits its discrimination ability over small lakes and rivers. The paper presents an automated method for downscaling the 500 m MODIS surface reflectance (SR) to 250 m to improve the spatial discrimination of water body extraction. The method has been tested at Co Ngoin and Co Bangkog in Qinghai-Tibet plateau. The downscaled SR and the derived water bodies were compared to SR and water body mapped from Landsat-7 ETM+ images were acquired on the same date. Consistency metrics were calculated to measure their agreement and disagreement. The comparisons indicated that the downscaled MODIS SR showed significant improvement over the original 500 m observations when compared with Landsat-7 ETM+ SR, and both commission and omission errors were reduced in the derived 250 m water bodies.


Polar Record ◽  
1996 ◽  
Vol 32 (180) ◽  
pp. 43-50 ◽  
Author(s):  
Z. Wang ◽  
F.I. Norman ◽  
J.S. Burgess ◽  
S.J. Ward ◽  
A.P. Spate ◽  
...  

AbstractBreeding activity of pairs of south polar skuas (Catharacta maccormicki) in the eastern Larsemann Hills, Princess Elizabeth Land, East Antarctica, was recorded in five of six austral summers between 1988 and 1994. More detailed observations of breeding success were made in the 1989/90 and 1993/94 summers. Although relatively few skuas nest in the study area, data suggest that there was inter-annual variation in numbers and locations of territories and chicks fledged. This variation is discussed in relation to increased human activities in the area (development of a summer base and more permanent stations) and to an enhanced access to human-derived foods. It is concluded that there has been some human impact on this species in the Larsemann Hills.


Author(s):  
K.B. Isbekov ◽  
E.V. Kulikov ◽  
S.Zh. Asylbekova

The article deals with the relationship between the hydrological regime of water bodies and the efficiency of fish reproduction. The hydrological regime of water bodies in years of different water content influences the reproduction and, accordingly, the quantitative and qualitative composition of ichthyocenoses. The easiest way to assess the efficiency of fish reproduction is by such an indicator as the productivity of juveniles, i.e. the number of juvenile fish per unit area or volume. The material for this work was carried out in large fishing reservoirs of the Republic of Kazakhstan in the process of fishery research (2013–2018). Comparison of hydrological parameters and productivity of juveniles by years shows their relationship. Correlation coefficient between water content (runoff) of the river Zhaiyk and juvenile yield +0.73 (data set for 11 years, reliable for the level of significance p = 0.01). The yield of juvenile fish from Lake Balkhash has a high correlative dependence on the inflow of water into the lake (r = +0.826) (massif 2013–2018, reliable for the level of significance p = 0.05). Correlation analysis showed that the productivity of juvenile fish in the Kapshagai reservoir has an average degree of dependence on water content (average annual level) (r = +0.641, reliable for the level of significance p = 0.05). Regular relationships between the water regime and the efficiency of reproduction (productivity of juveniles) of fish have been established. The efficiency of natural reproduction of commercial fish species in modern conditions of the water regime, water withdrawal for economic needs and the impact of fishing is significantly reduced, but with the implementation of the reclamation measures proposed in the work, its partial restoration is possible.


2021 ◽  
Vol 10 (1-2) ◽  
pp. 138-152
Author(s):  
Viktoriia O. Khomenko ◽  
Leonid V. Efimenko ◽  
Valentyna A. Vasilyeva

Abstract Entrepreneurial activity is one of the main factors in the development of the market economy of the state, the internal and external markets of Ukraine and innovative industries. Therefore, the main purpose of this article is to analyse the peculiarities of the legal position of a company after a decision has been made to terminate it. It is established that the liquidation of legal entities is performed without the transfer of the rights and obligations of the liquidated enterprise to other persons, i.e. without succession. Upon liquidation of the enterprise, its rights and obligations are terminated. The current civil legislation does not provide for the limitation of the powers of the liquidation commission in cases of liquidation based on a court decision. It is argued that the liquidation commission be terminated when an entry on termination of the activity of a legal entity is made in the unified state register.


Sign in / Sign up

Export Citation Format

Share Document