Agro-Environmental Evaluation of Irrigation Water from Different Sources, Together with Drainage and Escape Water of Rice Irrigation Systems, According to its Impact on Maize

摘要

Water supply deficit requires agro-environmental rationale for the use of alternative water sources to feed agricultural crops, viz.: industrial wastes, municipal drains, farm animal waste, drainage and escape water of rice irrigation systems. We have analyzed the quality of irrigation water from different sources, with regard to the content of cations, anions, water-soluble salts, power of hydrogen (рН), sodium adsorption ratio (SAR), etc. in it. In the course of greenhouse trial, we diagnosed its impact on the indicator crop (maize) (Zea mays L.) with its herbage crop stage of 10 leaves, supplied with water of varied quality. We proved the viability of improved drainage and escape water of rice irrigation systems in irrigated agriculture, owing to which maize herbage had been diminished, at an average, by 5.82 %. We verified the negative impact of irrigation water, which contains effluent disposals of metallurgical production, on croppers – it had contributed to diminishing the watered maize herb, at an average, by 39.27 %. Correlation analysis of the test data proved the closely interrelated feedback between the maize herbage amount and the content of cations, anions and water-soluble salts in irrigation water (coefficient of correlation r varied between 0.88 and 0.98). The worked-out linear regressive model for maize herbage, based on the content of water-soluble salts in irrigation water, together with SAR index (Y=2342.71-1.82×x1+366.78×x2), affirmed the validity of the pattern, discovered by means of correlation analysis.