Fluorine content in soils of Northern Pomoravlje

Abstract

Soil sampling was carried out in the Velika Morava river valley, covering the area from Velika Plana to the mouth of Morava to the Danube. The composite soil samples, representing alluvial soils (22 samples), cambisols (14) and smonitzas (4), were taken from plough layers, based on a regular square grid with intervals set at 5x5 km, covering total area of 100,000 ha. The total and available fluorine contents were determined in the soils samples. The highest average amount of total fluorine was found for alluvial soils (391 mg kg-1), then for smonitzas (348 mg kg-1) and the lowest one for cambisols (285 mg kg-1). These amounts are within normal fluorine content for soils (150-400 mg kg-1), although the maximum found levels were even about 500 mg kg-1. The available fluorine content was very low ( lt 1 mg kg-1), being mostly less than 0.2 % from its total amount, so it could be concluded that there was no danger from fluorine accumulation in the plants. Statistically significant correlation coefficient between total and available fluorine contents was not obtained. The total and available fluorine contents have mostly been in the correlation (with positive sign) with soil pH and the content of mechanical fraction silt+clay. Significant correlation coefficients between total fluorine content and the content of some heavy metals (Cr, Ni, Co, Cu, As) were also found, which indicated their mutual geochemical origin.

U dolini reke Velike Morave, u delu od Velike Plane do njenog ušća u Dunav uzeti su reprezentativni uzorci zemljišta iz orničnog sloja, po mreži kvadrata veličine 5x5 km. U njima su odredjeni ukupni i pristupačni sadržaji fluora. Istraživanjem su obuhvaćena aluvijalna zemljišta (22 uzorka) gajnjače (14) i smonice (4), što odgovara površini od 100. 000 ha. Za ukupni fluor najviše srednje vrednosti su nadjene u aluvijumima (391 ppm), zatim u smonicama (348 ppm) i najmanje u gajnjačama (285 ppm). Ove vrednosti se nalaze u granicama normalnih sadržaja za zemljišta (150-400 ppm), mada se maksimalne vrednosti kreću i oko 500 ppm. Pristupačni sadržaj fluora je u ispitivanim zemljištima jako nizak ( lt 1 ppm), što najčešće čini ispod 0,2 % od ukupnog fluora, pa se može zaključiti da ne postoji opasnost od akumulacije fluora u biljkama koje se gaje na ispitivanom području. Nije nadjena korelativna veza ukupnog sa pristupačnim fluorom. Sadržaji ukupnog i pristupačnog fluora su najčešće bili u korelaciji (pozitivnoj) sa pH vrednošću zemljišta, i sadržajem frakcije prah+glina. Nadjene su i korelativne veze ukupnog fluora sa sadržajima nekih teških metala (Cr, Ni Co, Cu, As), što ukazije na njihovo zajedničko geohemijsko poreklo.