Modeliranje toka vode i pronosa nitrata u nesaturiranoj zoni tla

master's thesis

• Title (english): Modeling water flow and nitrate transport in unsaturated soil zone
• Author: Mario Maloić
• Mentor: Vilim Filipović (mentor)
• Committee member: Vilim Filipović (predsjednik povjerenstva)
• Committee member: Ivan Mustać (član povjerenstva)
• Committee member: Vedran Rubinić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Soil Amelioration); Zagreb
• Defense date and country: 2018-09-19, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Na poljoprivrednim tlima se dušična gnojiva nerijetko koriste u velikim količinama koje biljke ne mogu u potpunosti usvojiti. Zbog navedenog može doći do ispiranja nitrata u dublje slojeve tla i/ili podzemne vode, a što je usko povezano s tokom vode u tlu. Budući da računalni modeli postaju sve važniji za procjenu onečišćenja podzemnih voda, cilj ovog istraživanja bio je procijeniti tok vode i transport nitrata na glejnim tlima i validirati model HYDRUS-1D na temelju prikupljenih podataka na lizimetrima instaliranim na Biđ polju. Podaci na terenu prikupljeni su na 6 lokacija (12 lizimetara) koji obuhvaćaju detaljna fizikalna svojstva tla, prikupljanje procjedne vode iz lizimetara i određivanje koncentracije nitrata, klimatske podatke, plodored uzgajanih kultura i informacije o primjeni gnojiva. Dobiveni rezultati su potvrdili dobru pouzdanost modela koji odgovara promatranom isteku vode iz lizimetara i dinamici nitrata tijekom razdoblja 2016. godine. Povećane koncentracije nitrata uočene su pretežno tijekom razdoblja bez usjeva ili tijekom zimskog / proljetnog razdoblja s povećanim količinama oborina. Rezultati ukazuju da intenzivna poljoprivreda može imati značajnu ulogu u onečišćenju podzemnih voda nitratima, čak i na teksturno težim tlima. Uz navedeno, model se može koristiti kao alat za predviđanje i sprečavanje onečišćenja podzemnih voda, omogućujući optimizaciju primjene gnojiva (količina, vrijeme, oblik).

Abstract (english)

Nitrogen fertilizers are frequently used on agricultural soils in large amounts which cannot be completely absorbed by plants and therefore leaching, usually closely linked with the soil water flow, is likely to occur. As computer models are becoming more important in the assessment of groundwater pollution, the objectives of this research were to assess water flow and nitrate transport in gley soils and to validate HYDRUS-1D model based on collected field data from lysimeters installed at the Biđ field (12 lysimeters at 6 locations). Extensive measurements of soil physical properties, lysimeter outflow and nitrate concentration were performed and coupled with the climatic data and collected information about the crop rotation and fertilizer application. Results confirmed good reliability of a model to fit the observed lysimeter water outflow and nitrate dynamics during 2014-2016 period. Increased nitrate concentrations were observed mostly during the period without crop, or during winter/spring period with a large amount of rainfall. Results suggest that groundwater nitrate concentration may significantly increase due to agricultural practices, even in soils with heavier texture. Results also show that the tested model, by indicating optimal application of different fertilizer (amount, timing, type), can be used as a tool for prevention of groundwater pollution.

• Keywords: kakvoća vode; numeričko modeliranje; pronos nitrata
• Keywords (english): water quality; numerical modeling; nitrate transport
• Language: croatian
• URN:NBN: urn:nbn:hr:204:777669
• Study programme: Title: Agricultural Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka poljoprivredne tehnike (magistar/ magistra inženjer/inženjerka poljoprivredne tehnike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-10-01 10:17:39