Cilj je istraživanja bio utvrditi na hidromelioriranom tlu, na različitim razmacima drenažnih cijevi (15 m, 20 m, 25 m i 30 m) ukupni drenažni istek, njegovo trajanje te prinos uljane repice i soje. Istraživanja su obavljena u dvije klimatski različite vegetacijske sezone (godine). U 2009/10. godini, u izrazito vlažnoj vegetacijskoj sezoni (1002,9 mm oborina) uzgajana je uljana repica, dok je u 2011. godini u ekstremno suhoj vegetacijskoj sezoni (348,4 mm oborina) uzgajana soja. U vlažnoj vegetacijskoj sezoni kod uzgoja uljane repice različiti razmaci cijevne drenaže imali su različit učinak u odvodnji suvišnih voda tla i visinu prinosa uljane repice. Na varijanti odvodnje s razmakom cijevi od 15 m utvrđena je najveća količina drenažnog istjecanja (324 mm), najkraće njegovo trajanje (118 dana) i najveći prinos (3,3 t/ha), dok je na varijanti odvodnje s razmakom cijevi od 30 m utvrđena najmanja količina drenažnog istjecanja (297 mm), najduže trajanje istjecanja (140 dana) i najmanji prinos (2,38 t/ha). U sušnoj vegetacijskoj sezoni kod uzgoja soje razmaci cijevne drenaže nisu imali utjecaja na visinu prinosa. Utvrđeni su podjednaki prinosi na svim varijantama, od 2,29 t/ha na varijanti odvodnje s razmakom cijevi od 30 m do 2,40 t/ha na varijanti odvodnje s razmakom cijevi od 20 m. Drenažni isteci nisu zabilježeni niti na jednoj varijanti odvodnje.The research goal was to determine the total drainage discharge, its duration and oilseed and soybean yields on hydroameliorated soil, with different drainpipe spacing (15 m, 20 m, 25 m and 30 m). Investigations were conducted in two climatically different growing seasons (years). Oilseed rape was grown in the particularly wet growing season (1002.9 mm precipitation) of 2009/10, while soybean was grown in the extremely dry growing season (348.4 mm precipitation) of 2011. In the wet growing season, different drainpipe spacing had different effects on excess water drainage and oilseed rape yields. In the drainage variant with 15-m drainpipe spacing, the highest drainage discharge (324 mm), its shortest duration (118 days) and the highest rapeseed yield (3.3 t/ha) were determined whereas in the 30-m drainpipe spacing variant, the lowest drainage discharge (297 mm), its longest duration (140 days) and the lowest yield (2.38 t/ha) were recorded. In the dry growing season, drainpipe spacing had no effect on soybean yields. Approximately equal yields were obtained in all variants, from 2.29 t/ha in the drainage variant with 30-m drainpipe spacing to 2.40 t/ha in the variant with 20-m drainpipe spacing. Drainage discharge was not determined in either variant
