Mineralogical, geochemical, micromorphological and agroecological properties of Monte Coronichi (Istria) paleosol : master’s thesis

Cilj ovog rada bio je istražiti mineraloške, geokemijske, mikromorfološke i agroekološke karakteristike pedosedimentnog crveničnog kompleksa na lokaciji Monte Coronichi.Terenskim istraživanjima u sklopu bilateralnog projekta „Usporedba terroira Istre, Beča i Wachaua“ izuzeta su tri seta uzoraka duž pedosedimentnog kompleksa do dubine 3m. Fokus istraživanja ovog rada bili su uzorci za pedološku i mikromorfološku analizu. Laboratorijskim istraživanjima napravljena je detaljna kemijska analiza, pedološka analiza tla, mikromorfološka analiza preparata, napravljene su i SEM fotografije na izuzetim uzorcima tla te Mikro CT fotografije izuzetih uzoraka korijenja. Najvažniji zaključci ovog rada su: (1) pedosedimentni crvenični kompleks formiran je na karbonatnoj podlozi te se sastoji od površinskog horizonta (P) i pet B – iluvijalnih horizonata, a nastao je nizom procesa trošenja, erozije te pedogentskim procesima. U kompleksu se jasno uočavaju tri ciklusa s generalnim trendom povećanja udjela čestica glina s dubinom. (2) crvenični kompleks je dominantno izgrađen od čestica dimenzije gline, što je potvrđeno imineraloškom analizom - minerali glina (kaoliniti i illitični materijal) dominantni su uz kvarc čiji udio pada s porastom dubine. Minerale glina potvrdila je i mikromorfološka analiza - nalaze se unutar mikromase i intruzivnih glinovitih prevlaka, a analizom uz pomoć SEM – a vidljivi su nanostrukturirani mikroagregati minerala glina; (3) mikromorfološkom analizom utvrđeno je da svi preparati imaju razvijen pedalitet, prevladavaju subpoliedrični do poliedrični agregati. Od osnovnih mineralnih komponenata preparati sadrže kvarc, tinjce, alkalijske feldspate, plagioklase te rijetke mineralne faze, cirkon i kijanit (disten). Glavni litoklasti su fragmenti kvarcita, rožnjaka i boksita. U gornjem dijelu profila dominira spužvasto-vagi mikrostruktura, a c/f distribucija mikromase je dvostruka-razmaknuta. Mikrostruktura donje dijela profila je šupljikasto-pukotinasta, a c/f distribucijamikromase je otvorena porfirna. Glavni tipovi b-građe u preparatima su točkasto-pjegasti, porostrijasti, granostrijasti, a uočen je i srpastostrijasti, unakrsnostrijasti, monostrijasti te paralelnostrijasti tip b-građe mikromase. Preparatima dominiraju intruzivne pedotvorevine (nodule, litorelikti i glinoviti klasti) te impregnativne matriks pedotvorevine, a u pojedinim preparatima uočene su i teksturne i deplecijske pedotvorevine.The aim of this Master’s Thesis was to investigate mineralogical, geochemical, micromorphological and agroecological properties of paleosoil located at Monte Coronichi in Istria. During the field work investigation carried out for the project entitled "Comparison of terroir Istria, Vienna and Wachau", three sets of samples were taken along around 3 meters of the pedosediment complex. This Master’s Thesis focused on pedological and micromorphological analysis samples. Laboratory work consisted of a detailed chemical, pedological and micromorphological analysis of the paleosols, as well as soil samples, which were analyzed using SEM. Root samples were analyzed using a micro CT. The most important conclusions of this Master’s Thesis are: (1) pedosediment terra rossa complex was formed on carbonate basement, it contains surface horizon (P) and five B (illuvial) horizons and it was formed by intensive weathering, erosion and pedogenic processes. Three cycles are clearly visible in the complex and a general trend of increasing clay fraction content with depth can be observed, (2) pedosediment terra rossa complex consists of a clay particles which was confirmed by mineralogical analysis – clay minerals (kaolinite and illitic material) are dominant alongside quartz, whose content is reduced with depth. Micromorphological analysis confirmed the presence of clay minerals. They fill the area within the micromass and intrusive clay coatings. SEM analysis also confirms the presence of clay minerals, which occur as nanostrucurated microagregates of clay minerals (3) micromorphological analysis established that all thin sections present developed pedality, mostly subangular and angular peds. In coarse material of groundmass thin sections contain quartz, mica, feldspars and zircon and kyanite in heavy mineral fraction. Lithic material consists of quartzite, chert and bauxite. In the upper part of profile spongy-vughy microstructure is dominant, and c/f distribution of micromass is double-spaced porphyric. In the lower part of profile, channel-chamber microstructure is dominant, and c/f distribution of micromass is open porphyric. Main types of b-fabric are stipple-speckled, porostriated, granostriated, while crescent striated, cross-striated, monostriated and parallelstrated are also present. Intrusive pedofeatures (nodules, lithorelicts, and clay clasts) and impregnative matrix pedofeatures are dominant in thin sections, while fabric and depletion pedofeatures are present in some thin sections