Analysis of droughts due to the operation of water structures: Gidra river case study

The paper deals with an analysis of a drought in the small basin of the Gidra River in Slovakia due to problems with the abstraction of water from small reservoirs and ponds. A detailed hydrological assessment of the M-daily discharges for a long-term period was based on a dataset from the only gauging station on the upper part of the river. Because of the existing water structures with prescribed operations during the year, hydrometric and geodetic measurements were taken by the authors. The solution to this problem represents the conditions for the minimum required Q355 discharge in the river anytime and anywhere. This can only be solved with a master operational manual for the whole river to be able to flexibly react to the current hydrological situation.

Evaluation of Catchments’ Similarity by Penalization in the Context of Engineering Tasks—A Case Study of Four Slovakian Catchments

The present study deals with the similarity of catchments, which is a preliminary investigation before performing various water resource analyses and computations regarding other catchments, e.g., catchments’ similarity may be utilized in the context of analogous calculations of river flows in catchments without measured flows. In this paper, the penalization method of evaluating similarity is proposed; this method is appropriate for tasks in which fewer catchments are analyzed for engineering purposes. In addition to the various physical characteristics of the catchment, the “catchment’s calibrability” property is also formulated and evaluated. A methodology that used specific flows from catchments in a case study from Slovakia successfully verified the proposed penalization method. This verification confirmed that physical similarity, as evaluated using the proposed penalization methodology, also helps to identify hydrological similarity, i.e., finding the most similar catchment to a given catchment in terms of the rainfall-runoff process. Such a finding can be helpful, e.g., in the computation of the mentioned flows in ungauged catchments. Determining unmeasured flows can help to solve many engineering tasks, such as various technical calculations during the design of small reservoirs, defining the potential of a given stream for supplying irrigation, flood protection, etc.

POPULATIONS OF ARTEMIA CRUSTACEANS OF KARABASSKY FLOODS OF PRIBALKHASHYE

The article presents the analysis of biological parameters of parthenogenetics of Artemia crustaceans of the hypergaline reservoirs of Kazakhstan. In the lakes under study there are shown the changes of the total crustacean biomass decreasing from high-productive to low-productive. Most of the reservoirs with Artemia in Kazakhstan are characterized by the presence of Artemia parthenogenetic populations with the absence or extremely small presence of males. The aggregation of males in significant numbers may indicate the tension of the ecological situation in the reservoirs and the desire of the population to increase the survival and stability of the offspring. It has been stated that all age periods of crustacean maturation are found in the reservoirs. At the same time, the basis of Artemia populations in all studied lakes are the youngest stages - nauplius, which form 53-86% of the total number of Artemias. In lakes Artemia crustaceans are presented by bisexual parthenogenetic race, with all age stages of development during the summer - autumnal period of observations. The hydrochemical mode of hypergaline lakes of Karabassky floods is favorable for activity of Artemia Branchiopoda crustaceans. The size of crustacean biomass populations in Lake Balhash change on seasons ranging from low to very high. Lake No. 1 is highly productive in Artemias in the summer, and lake No. 2 - in the spring. Such difference in temporary aspect is caused by existence of various generations in the populations of the crustaceans on seasons. The data obtained prove the high potential of the studied small reservoirs of the Balkhash region in relation to autumn plankton cysts

Macrozoobenthos communities of small reservoirs of the Zhambyl region of the Republic of Kazakhstan

The benthic fauna of 15 reservoirs located in the territory of the Zhambyl region in the Baizak, Zhambyl, Sarysu and Ryskulovsky districts is characterized. Based on the results obtained, it can be concluded that the benthic fauna of the studied reservoirs is heterogeneous, the species composition of zoobenthos in various reservoirs ranged from 1 (Kosheney reservoir) to 6 (Kenes Lake) taxa. The number was in the range 40–480 copies/m², with a biomass 0.03–27.22 mg/m². The bioproductivity of reservoirs in the Baizak district varied from a very low class of α-oligotrophic type to a high class of β-eutrophic type, the number was in the range 160–480 specimens/m², with a biomass 0.76–27.22 mg/m². In the Zhambyl region, from 3 to 6 invertebrate species were identified as part of the macrozoobenthos. The abundance varied 340–360 specimens/m², with a biomass 7.0–17.99 mg/m². Based on the average indicators of the zoobenthos biomass, the level of productivity of the reservoirs of the Zhambyl district varied from the middle class of the β-mesotrophic type to the elevated class of the α-eutrophic type. The zoobenthos of the reservoirs of the Sarysu district varied from 3 to 6 taxa, the number of zoobenthos in the reservoirs ranged from 80 to 160 specimens/m², the biomass 0.36–1.1 mg/m². The value of the biomass of zoobenthos in the reservoirs of the Sarysu district is characteristic of lakes of a very low productivity class, alpha-oligotrophic type. The species diversity of zoobenthos in the reservoirs of the Ryskulovsky district varied from 1 to 3 species. The number varied 40–80 copies/m², the biomass 0.03–17.33 mg/m². The productivity of the reservoirs of the Ryskulovsky district varied from a very low class of α-oligotrophic type to an increased class of α-eutrophic type. According to the frequency of occurrence in all reservoirs, the class of oligochaetes dominated — 20% of the total number of taxa. The Serensen coefficient of species similarity between benthic communities in the districts was 56%.

Data bank of irrigation ponds of the Saratov region

The article is devoted to the issue of improving the quality of operation of small reservoirs of the left-bank districts of the Saratov region through the development and implementation of an automated data bank of their safety parameters. It provides a generalized scheme for the functioning of an automated databank, as well as the structure of the database, which should include 27 relational files containing all the necessary information for declaring the safety of hydraulic structures of reservoirs and calculating the harm to the population and subjects of economic and economic activity, various natural and man-made objects in case of accidents. The creation of such an automated data bank will improve the quality of monitoring the condition and management of hydraulic structures of the reclamation systems of the Saratov Trans-Volga region and will pay off in 5 years.