MODERN STATE, DYNAMICS OF CHANGES AND PROSPECTS FOR THE DEVELOPMENT OF HYDROTECHNICAL RECLAMATIONS IN DNIPROPETROVSK REGION
Authors: Rudakov L. M. , Hapich H. V. 
Published: November 2019

Formulation of the problem. Irrigation is one of the priority areas of agricultural development for Ukraine. According to numerous studies, it has been determined that restoration of irrigated agriculture is a prerequisite for adapting the agricultural sector of the economy to climate change and ensuring Ukraine's food security. Dnipropetrovsk region was among the territories with the largest area of irrigated land. The vast majority of irrigation systems in the region were built in the 70-80's of the last century and operated for about 50 years, and the last reconstruction of the capital reconstruction was carried out more than 30 years ago. About 198.7 thousand hectares of irrigated land are recorded on the territory of the region, of which 163 thnd ha (82% of available capacity) are not used as irrigated. At the same time, operating systems on the area of 35,7 thnd ha (18% of available) are not working at full capacity. Under the condition of reconstruction of the internal irrigation network, it is promising to restore irrigation on an area of 80.4 thnd. ha.

Research results. Irrigation of agricultural crops in the Dnipropetrovsk region occurs on the right and left bank of the Dnipro River in 18 administrative districts. An analysis of the dynamics of the change on the right-bank part indicates a trend of reduction of irrigated land by 1.3 times in 2014 as compared to the same indicator in 2004. The irrigated areas of the left-bank part of the Dnipropetrovsk region have a positive tendency to build up. The dynamics of the change in the period of 2004-2014 indicates that the irregular area is slightly but gradually increased 1.36 times.For the purpose of determining the quality of irrigation water and its suitability for irrigation by structural subdivisions subordinated to the regional office of water resources in the Dnipropetrovsk region, 130 samples were sampled at 56 stationary observation points for chemical analysis. Samples of water were selected near the main pumping stations and control basins, in the heads of main channels, from large and small rivers and ponds.The analysis of the results testifies to the threatening tendency of gradual deterioration of the quality of irrigation water. For example, in comparison with the figures for 2004 in relation to 2014, the area of irrigation with water of the 1st class decreased by 2.7 times from 16.85 thnd ha to 6.34 thnd ha. Almost stable trend has the irrigation area, which was watered with 2nd grade water, which increased by 1.35 times and, with the exception of the indicators in 2010, averaging about 12 thnd ha. The most threatening trend is the increase in areas of irrigated water that is not suitable for irrigation without the prior improvement of its physical and chemical parameters. Such territories have grown almost 3 times from 2,2 thnd ha to 6,1 thnd ha.

Conclusions. The unsatisfactory technical condition of the conducting network of most canals and drainage systems, violation of irrigation regime and outdated irrigation technique, worsens the reclamation state of a significant part of the irrigated lands of the Dnipropetrovsk region. In this regard, it is necessary to introduce a system of detailed monitoring of land prone to secondary salinity, based on technologies of remote mapping WL-methods. In addition, it is necessary to widely apply methods of field simplified operational control of the technical state of the components of irrigation networks. It is necessary to perform repair and renovation works in a timely manner that will reduce unproductive water losses for filtration from irrigation systems and prevent soil salinization, as well as rational use of water resources. Due to the threatening trend, particular attention should be paid to the quality and quantity of irrigation water. In the absence of control by the authorities on volumes, concentrations and major sources of pollution of surface and groundwater, it is possible that irrigation systems in the future should include technological lines to improve the physical and chemical parameters of irrigation water. The economic feasibility of the issue requires further study.