Razvoj metodologije praćenja višegodišnjeg zagađenja životne sredine preko akumulativnosti elemenata u prstenovima prirasta i kori drveta ariša (Larix europaea Lam.) i duglazije (Pseudotsuga menziesii Mirb.)

Abstract

Biljni pokrivač, naročito šumsko drveće, se javlja kao aktivni faktor u procesu prihvatanja zagadjenja iz atmosfere, i predstavlja prvi nivo taloženja atmosferskih zagadjivača, a zemljište krajnji receptor. Kod šumskih ekosistema postoji samo jedan tip ulaska elemenata, ali postoji više puteva transfera zbog prisustva prizemne flore i spratova drveća. Drveća koja rastu u umerenoj klimatskoj zoni, gde su izražene sezonske promene, imaju osobinu da formiraju po jedan prsten prirasta godišnje. Prstenovi prirasta ili godovi su približno koncentrični slojevi drveta, koji nastaju radom kambijuma u jednoj vegetacionoj sezoni drveta. Prstenovi prirasta predstavljaju široko dostupan izvor dugogodišnjih podataka o prošlim vremenima i kao takvi su jedinstven svedok stanja životne sredine. Hemijski sastav drveta stoga može odražavati sastav sredine u kojoj je drvo raslo. Mnoge studije u urbanim i idustrijskim sredinama, otkrile su da hemijski sadržaj drveta može ukazati na promene u životnoj sredini tokom vremena i omogućiti rekonstrukciju zagadjujućih epizoda. Malo toga se zna o koncentraciji elemenata u prstenovima prirasta drveća ruralnih sredina i šumskih ekosistema, a još manje o koncentraciji elemenata u prstenovima prirasta u SR Srbiji. U okviru ovih istraživanja koturovi dve četinarske vrste: ariša (Larix europaea Lam.) i duglazije (Pseudotsuga menziesii Mirb.) sa tri lokacije u Republici Srbiji (Avala, REIK-Kolubara i Kučevo) su uzorkovani i razvrstani u periode od po tri godine. Merene su koncentracije makro (Ca, Mg, K, P) i mikro (Fe, Mn, Cu, Zn, Al, Cd, Pb i Sr) elemenata u prstenovima prirasta, kori i zemljištu optički emisionim spektrometrom sa induktivno spregnutom plazmom (ICP-OES). Uzorci zemljišta su prethodno pripremani sekvencijalnom ekstrakcijom u cilju dobijanja ukupne, dostupne i potencijalno dostupne koncentracije elemenata u zemljištu...

Plant cover, particularly forest trees, is emerging as an active factor in the acceptance of pollution from the atmosphere, and plants form the first level of deposition of these pollutants, while soil is the ultimate receptor. In forest ecosystems, there is only one type of elements entry, but there are multiple transfer pathways due to the presence of ground flora and tree floors. Trees that grow in temperate regions, where the seasonal changes are pronounced, usually form visible annual growth ring. Growth rings or tree-rings are approximately concentric wood layers, which are the result of cambium work in one growing season. Tree-rings are widely available source of long-term data about past times and as such are unique witness of the environment condition. The chemical composition of wood may therefore reflect the environment composition in which the tree grew. Many studies in urban and industrial areas revealed that wood chemical content can point on changes in the environment through time and allow the reconstruction of pollution episodes. Little is known about the tree-ring element concentrations in rural and forest ecosystems, and even less about the element concentrations in tree- rings in Serbia. In this study stem disks of two coniferous species: larch (Larix europaea Lam.) and Douglas-fir (Pseudotsuga menziesii Mirb.) from three locations in the Republic of Serbia (Avala, REIK-Kolubara and Kučevo) were sampled and divided into periods of three years. Macro (Ca, Mg, K, P) and micro (Fe, Mn, Cu, Zn, Al, Cd, Pb and Sr) element concentrations in tree-rings, bark and soil were measured by inductively coupled plasma atomic emission spectrometry (ICP-OES). Soil samples were previously prepared by a sequential extraction method in order to obtain total, available and potentially available element concentrations in soil. The analysis of the measured macro and micro element concentrations in the tree vegetative parts is of great importance for assessing observed ecosystem as a whole...