Chemical properties of Terra rossa under different land use types

Crvenica je rezidualno kambično tlo crvene boje nastalo na vapnencima i dolomitima pod utjecajem mediteranske klime. Različiti načini korištenja zemljišta, tj. načini obrade, gnojidbe i primjene zaštitnih sredstava, rezultiraju promjenama kemijskih, fizikalnih i bioloških svojstava tla. Cilj ovog istraživanja bio je utvrditi odabrana svojstva crvenica pri različitom korištenju (maslinarstvo, vinogradarstvo) i pod prirodnom vegetacijom kao kontrolom, usporediti analitičke podatke za svaki način korištenja zemljišta s kontrolom i međusobno, te utvrditi promjene. Istraživanje je provedeno tijekom travnja 2017. godine, na sedam lokacija s područja općine Primošten u Šibensko‐kninskoj županiji. Na svakoj lokaciji uzeti su prosječni uzorci površinskog horizonta tla u vinogradu, masliniku i pod makijom (kontrola), što čini ukupno 21 uzorak tla. U tlu je određivana reakcija (HRN ISO 10390:2005), količina humusa (metoda po Tjurinu), te fiziološki aktivni fosfor i kalij (AL‐metodom). Reakcija istraživanih tala bila je slabo kisela do neutralna (pH‐H2O = 6,88‐7,85; pH‐KCl = 6,28‐7,21). Tlo pod maslinama imalo je prosječno niži pH (KCl) 6,80, a tlo pod vinogradom prosječno viši (7,11) u odnosu na izvorno tlo (7,06). Sadržaj humusa varirao je od 2,53 do 9,80%, odnosno tla su bila slabo do jako humozna. U antropogeniziranim crvenicama utvrđeni su prosječno niži sadržaji humusa (pod vinogradima 5,14%; pod maslinicima 7,42%) u odnosu na kontrolu (8,75%). Sadržaj fiziološki aktivnog fosfora varirao je od 1,21 do 41,05 mg P2O5/100g tla. Opskrbljenost fiziološki aktivnim fosforom kretala se od slabe u tlu pod makijom (3,80 mg P2O5/100g tla) i vinogradom (9,03 mg P2O5/100g tla) do dobre u tlu pod maslinikom (31,49 mg P2O5/100g tla). Sadržaj fiziološki aktivnog kalija je varirao od 26,5 do preko 40 mg K2O/100g tla, te je opskrbljenost fiziološki aktivnim kalijem bila vrlo dobra do bogata. Tla pod vinogradom i maslinicima imala su prosječno viši sadržaj kalija (35,0 mg K2O/100g tla, odnosno >40 mg K20/100 g tla) u odnosu na izvorne crvenice pod makijom (30,7 mg K2O/100g tla). Vinogradarska i maslinarska proizvodnja povisile su sadržaj fiziološki aktivnih hraniva, a smanjile sadržaj humusa u tlu. Vinogradarska proizvodnja povisila je pH izvornog tla, a maslinarska ga snizila.Terra rossa is a red cambic soil that develops on limestones and dolomites under the influence of Mediterranean climate. Different land use types, namely different types of cultivation, fertilization and application of protective agents, are resulting in changes of chemical, physical and biological properties of soil. The aim of this study was to determine some selected properties of terra rossa under different land use types (olive grove and vineyard) and under natural vegetation as control, to compare the analytical data for every land use type with control and each other, and to identify changes. The study was conducted during April 2017 on seven locations in Primošten district in the Šibenik‐Knin county. Average soil samples were taken from surface horizons in vineyard, olive groves and under macchia (as control) on every location, 21 samples of soil in total. The samples were analyzed for soil reaction (HRN ISO 10390:2005), humus content (Tjurin method) and content of physiologically active phosphorus and potassium (AL‐method). Soil reaction was slightly acid to neutral (pH‐H2O = 6.88‐7.85; pH‐KCl = 6.28‐7.21), Soil under olive groves had lower pH(KCl) 6.80, while soil under vineyards had higher pH (7.11) in comparison to control (7.06). Humus content ranged from 2.53% to 9.80%. Under vineyards and olive groves, lower humus contents were determined (5.14 and 7.42%, respectively) in comparison to control (8.75%). Physiologically active phosphorus content varied from 1.21 to 41.05 mg P2O5/100g of soil. Supply of physiologically active phosphorus varied from low in control and vineyards (3.80 and 9.03 mg P2O5/100g of soil, respectively) to good in olive groves (31.49 mg P2O5/100g of soil). Physiologically active potassium content ranged from 26.5 to over 40 mg K2O/100g of soil, which made physiologically active potassium supply very good to rich. Soils under vineyards and olive groves had in average higher K2O content (35.0 and >40 mg K20/100 g of soil, respectively) in comparison to control (30.7 mg K2O/100g of soil). Olive and vine growing had enriched soils with physiologically active nutrients, but decreased their humus content. Vineyard production increased pH of soil, while olive production decreased it