The occurrence of several microbial groups in different soil types

Abstract

Microorganisms are a heterogeneous group of organisms whose enzymatic systems take 60-90% of the total metabolic activity in soil. Dominance of certain groups of microorganisms affects the processes of soil synthesis and decomposition and it determines the quality of soil and its applicability for the production of safe food. Soil tillage can affect microbial activity both positively and negatively, and it can have an indirect influence on the fertility of the soil as well. Microbiological properties were examined according to profile depth in the following five soil types: fluvisol hydromorphic gley soil, colluvium, solonetz, and chernozem. Soil samples for microbiological analyses were taken in June of 2005. Overall soil biological activity was monitored based on total microbial abundance and the number of diazotrophs, ammonifiers, actinomycetes and fungi. In all of the soil types biological value was high down to 30 cm depth. Total microbial abundance decreased with increasing soil depth and no fungi or actinomycetes were found in the deeper layers. Total microbial abundance and the number of ammonifiers and free M-fixing bacteria were the highest in solonetz. The most azotobacters were found in the hydromorphic gley soil, while fungi and actinomycetes were the most abundant in fluvisol.

Mikroorganizmi su veoma heterogena grupa organizama i sa svojim enzimatskim sistemima učestvuju sa 60-90% u celokupnoj metaboličkoj aktivnosti zemljišta. Dominantnost pojedinih grupa mikroorganizama usmerava procese ka sintezi ili razgradnji i time određuje kvalitet zemljišta za proizvodnju zdravstveno ispravne hrane. Obrada zemljišta može uticati pozitivno ili negativno na mikrobiološku aktivnost, što se neposredno odražava i na plodnost. Mikrobiološka svojstva ispitana su na pet tipova zemljišta (fluvi - sol močvarno-glejno, koluvium, solonjec i černozem), po dubini profila. Uzorci zemljišta za mikrobiološke analize uzeti su u junu 2005. godine. Opšta biološka aktivnost zemljišta određena je na osnovu ukupnog broja mikroorganizama, zastupljenosti diazotrofa, amonifikatora, aktinomiceta i gljiva. Biogenost na svim tipovima zemljišta visoka je na dubini do 30 cm. Brojnost mikroorganizama opadala je sa dubinom profila, a u dubljim slojevima nisu konstatovane gljive i aktinomicete. Ukupan broj mikroorganizama, broj amoni fikatora i oligonitrofila bio je najveći u zemljištu tipa solonjec azotobaktera na močvarno-glejnom, dok su gljive i aktinomicete bile najbrojnije na fluvisolu.