| Abstract | Prekomjerna kiselost tla je faktor ograničenja koji određuje učinkovitost biljno-uzgojnih zahvata na mnogim poljoprivrednim gospodarstvima u Hrvatskoj. Kao rješenje provodi se vapnjenje koje uz pozitivne strane (ovisno o podrijetlu vapnenih materijala) može imati i negativne implikacije na okoliš, osobito s aspekta akumulacije teških metala u tlu. Cilj diplomskog rada bio je utvrditi utjecaj šestogodišnje primjene rastućih doza različitih materijala za vapnjenje na akumulirani sadržaj kroma, bakra, nikla, olova, cinka i kobalta u tlu. Istraživanje je uključivalo analizu 20 arhiviranih uzoraka tla (5 tretmana i 4 ponavljanja) prikupljenih 2020. godine sa stacionarnog poljskog pokusa smještenog u središnjem dijelu Hrvatske (lokalitet Popovača) nakon šestogodišnje primjene rastućih doza (0, 2 i 4 t/ha) različitih vapnenih materijala (agrovapno i hidratizirano vapno). Sadržaj Cr, Cu, Ni, Pb, Zn i Co utvrđen je pXRF metodom, reakcija tla se utvrdila potencijometrijom, a metodom po Sokolovu sadržaj mobilnog aluminija. Nakon šestogodišnje primjene materijala za vapnjenje, reakcija tla (pH vrijednost) značajno se povisila s 4,53 na 5,85, dok se istovremeno sadržaj mobilnog aluminija smanjio s 2,28 mg/100 g tla na 0,23 mg/100 g tla. Sadržaj promatranih metala u tlu dodatkom primijenih materijala za vapnjenje nije značajno varirao u odnosu na kontrolu i kretao se u rasponu od: 99,3 mg Cr/kg do 115,5 mg Cr/kg; 18,8 mg Cu/kg do 23,3 mg Cu/kg; 31,8 mg Ni/kg do 40,8 mg Ni/kg; 18,8 mg Pb/kg do 20,8 mg Pb/kg; 81,5 mg Zn/kg do 87,0 mg Zn/kg; 28,4 mg Co/kg do 23,1 mg Co/kg. Ukupna šestogodišnja primjena agrovapna i hidratiziranog vapna u rasponu od 10-30 t/ha mogla je doprinijeti neznatnim količinama akumuliranih metala u tlu (0,027-0,082 mg Cr/kg; 0,006-0,018 mg Ni/kg; 0,008 – 0,024 mg Cu/kg; 0,014 – 0,041 mg Pb/kg; 0,024-0,071 mg Zn/kg) i rezultati ukazuju da je primjena materijala za vapnjenje doprinijela relativnom smanjenju sadržaja olova, cinka i kobalta tlu. Istraživano tlo u cijelosti je onečišćeno kromom, a dijelovi pokusne površine pod kontrolnim tretmanom i tretmanom s ukupno primijenjenih 10 t/ha agrovapna onečišćeni su niklom i cinkom. |
| Abstract (english) | Excessive soil acidity is a limiting factor that affects the effectiveness of agricultural practices on many farms in Croatia. As a solution, liming is implemented, which can have both positive (depending on the origin of the liming materials) and negative implications for the environment, especially regarding the accumulation of heavy metals in the soil. The aim of the research was to determine the six years impact of application of increasing doses of different liming materials on the accumulated content of chromium, copper, nickel, lead, zinc, and cobalt in the soil. The study included 20 archived soil samples (from 5 treatments and 4 replication) collected in 2020 from a stationary field experiment located in central Croatia (Popovača site) after six years of applying increasing doses (0, 2, and 4 t/ha) of various liming materials (agricultural lime and hydrated lime). The content of Cr, Cu, Ni, Pb, Zn, and Co was determined using pXRF (portable X-ray fluorescence) method, soil reaction (pH value) was assessed by potentiometric method, and the mobile aluminium content was determined by the Sokolov method. After six years of liming materials application, the soil pH significantly increased from 4.53 to 5.85, while the mobile aluminium content simultaneously decreased from 2.28 mg/100 g soil to 0.23 mg/100 g soil. The content of observed metals in the soil did not significantly vary compared to the control and ranged as follows: 99.3 mg Cr/kg to 115.5 mg Cr/kg; 18.8 mg Cu/kg to 23.3 mg Cu/kg; 31.8 mg Ni/kg to 40.8 mg Ni/kg; 18.8 mg Pb/kg to 20.8 mg Pb/kg; 81.5 mg Zn/kg to 87.0 mg Zn/kg; 28.4 mg Co/kg to 23.1 mg Co/kg. The total six-year application of agricultural lime and hydrated lime in the range of 10-30 t/ha could contribute to minimal amounts of accumulated metals in the soil (0.027-0.082 mg Cr/kg; 0.006-0.018 mg Ni/kg; 0.008 – 0.024 mg Cu/kg; 0.014 – 0.041 mg Pb/kg; 0.024-0.071 mg Zn/kg), and the results indicate that liming materials application led to a relative reduction in lead, zinc, and cobalt content in the soil. The soil in investigation location is contaminated with chromium, while parts of the experimental area under control treatment and treatment with a total application of 10 t/ha of agricultural lime are contaminated with nickel and zinc. |
