Sadržaj Cd i pb u nerazvijenim zemljištima na serpentinitu i biljnom materijalu na području Nnacionali park Tara

Abstract

Ultramafiti (serpentiniti) predstavljaju grupu magmatskih ili metamorfnih stena, koje se karakterišu visokim koncentracijama Mg, Fe, Ni, Cr i Co, kao i niskim koncentracijama Ca, P i K, sadrže manje od 45 % silicijuma (SiO2). Planina Tara predstavlja prirodno bogatsvo zapadne Srbije gde površine pod serpentinitima zauzimaju 28%. Istraživači se slažu da je flora serpentinskih područja jedinstvena i botanički veoma važna. Specifičnost flore i razvoj vegetacije na serpentinitima karakterišu posebni mehanizmi prilagođavanja biljnih vrsta na povećanu koncentraciju nekih teških metala u zemljištu sa niskim sadržajem esencijalnih elemenata (hranljivih materija). Cilj ovog rada je da se ispita uticaj serpentinske geološke podloge na pojavu određenih biljnih vrsta u početnim fazama razvoja biljnih zajednica. Zemljište je uglavnom uzorkovano iz stenskih pukotina što predstavlja rane faze razvoja zemljišta (Litosol) gde se uticaj i poreklo metala iz stene mogu smatrati najočiglednijim. Analiziran je sadržaj kadmijuma (Cd) i olova (Pb) u geološkoj podlozi, zemljištu i biomasi biljaka, kako bi se odredio nivo i opseg prirodnog i antropogenog zagađenja kao i podaci o depoziciji iz EMEP programa (European Monitoring and Evaluation Programme). Rezultati pokazuju da je sadržaj olova i kadmijuma u uzorcima zemljišta i biljaka veći od sadržaja u odgovarajućem uzorku stena, što ukazuje da je poreklo povećanog sadržaja Pb i Cd može biti iz antropogenih izvora. Depozicija (podaci iz EMEP programa) Pb i Cd, koja je analizirana za period od 1990. do 2018. godine, ukazuje na značajan kumulativni efekat. Kumulativne vrednosti na istraživanom području iznose 91,51 kg/km2 olova, dok je vrednost kadmijuma 1665 g/km2 , što NP Tara svrstava u natprosečno zagađeno područje u R. Srbiji.

Ultramafic (serpenites) are a group of igneous or metamorphic rocks, which are characterized by high concentrations of Mg, Fe, Ni, Cr, and Co, along with low concentrations of Ca, P, and K, contain less than 45% silicon (SiO2). Tara Mountain is natural good of western Serbia where areas under serpentinites occupy 28%. Researchers agree that the flora of serpentine areas is unique and botanically very important. The specificity of the flora and the development of vegetation on serpentinites are characterized by special mechanisms of plant species adaptation to increased concentrations of some heavy metals in the soil with low content of essential elements (nutrients). This paper examines the influence of serpentinite geological substrate on the occurrence of certain plant species in the initial stages of plant community development. The soil was mainly sampled in rock crevices in the early phases of soil development (Lithosols) where the influence and origin of the metals from the rock can be considered the most obvious. Content of cadmium (Cd) and lead (Pb) in geological substratum, soil and plants biomass is analysed in order to differentiate levels and extents of natural and anthropogenic pollution and also deposition data from the EMEP program (European Monitoring and Evaluation Programme). Results show that the content of lead and cadmium in the soil and plant samples are higher than the content in the corresponding rock sample, except for two soil samples, in which the content of Cd is lower. Thissuggest that the origin of the increased Pb and Cd content might be from anthropogenic sources. Deposition (data from EMEP program) of Cd and Pb, which was analysed for the period from 1990-2018, indicate significant cumulative effect. The values of cumulative deposition in research area have a value of 91,51 kg/km2 lead, while the value of cadmium is 1665 g/km2 , which classifies NP Tara in above-average polluted area in R. Serbia.