Analysis of water supply of ameliorated lands within the drainage system “Marianivka” of Rivne region

Abstract

Goal. To analyze the water security of reclaimed lands of the drainage system “Marianivka” for the possibility of conducting efficient agricultural production. Methods. Field, information-analytical, computational, mathematical, and statistical. Results. The results of field surveys and research conducted in 2020 are presented. Hydrological calculations were performed based on river analogs during the entire observation period by the generally accepted methodology and current standards. According to the results of the analysis of the primary documentation and visual inspection, it was established that the current technical condition of the drainage system “Marianivka” did not allow to regulate the water-air regime of reclaimed lands. The need for bilateral regulation is stipulated by the insufficient water supply of agricultural land in low and very low water years due to significant uneven intra-annual distribution of runoff, in particular very small volumes of runoff during the growing season. Conclusions. The water flow on the drainage system “Marianivka” is characterized by significant unevenness. In high- and middle-water years, the spring flood period accounts for almost half of the annual runoff, and in low- and very low-water years, spring runoff can exceed 80% of runoff per year. In low-water years, the runoff in May is about 10% per annum, and in the next 4 months — in the amount of only 2.5% in low-water years and 1.6% in very low-water years. Accordingly, in low-water years, the volume of runoff for the same 4 months is 39100 m3, and in very low water — only 14700 m3. Ensuring the watering of reclaimed lands within the drainage system “Marianivka” and regulation of groundwater levels in the summer is possible only through the accumulation of runoff in May and partial accumulation of flood runoff by arranging additional tanks in areas where there is no threat of flooding.