Stimulation of soil microbiological activity by clinoptilolite: The effect on plant growth

Abstract

Zeolites can mitigate ammonium losses to the environment by taking up the ions from sources such as farmyard manure and ammonium-bearing fertilizers. This ability can improve nitrogen fertilizing practice given that ammonium ions loaded onto zeolite are available for plant uptake. The main goal of this study was to assess the influence of zeolite (clinoptilolite) and ammonia-loaded clinoptilolite on growth and yield of red clover (Trifolium pratense L.), as well as their influence on the microbial dynamics in soil. Plants sown in pots were cut four times, and dry matter yield (DM) of each harvest was weighed. The number of culturable bacteria, moulds, ammonifiers, Azotobacter sp. and actinomycetes was determined at the beginning of the experiment, and after each harvest. Two control treatments (soil without fertilizer and soil supplemented with mineral fertilizer - CAN) were included in the study. The application of ammonia-loaded clinoptilolite positively and significantly affected the microbial activity and provided higher yields (from 4.9 g/pot in ammonia-loaded clinoptilolite treatment to 4.3 g/pot in soil with zeolite treatment). Our results suggest that the addition of clinoptilolite to organic fertilizers (manure, composts) could be recommended. The increase of microbial communities’ abundances and their activity represented the key benefit from clinoptilolite application.

Zeoliti mogu ublažiti otpuštanje amonijaka u prirodu preko uzimanja jona iz izvora kao što su stajnjak i đubriva bogata amonijakom. Ova sposobnost može unaprediti đubrenje azotom preko zeolitom usvojenih amonijum jona koji bi tako postali dostupni za usvajanje biljkama. Cilj ovih ispitivanja je bio procena uticaja zeolita (klinoptilolita) i zeolita obogaćenog amonijakom na rast i prinos crvene deteline (Trifolium pratense L.), kao i na njihovu ulogu u mikrobiološkoj dinamici zemljišta. Biljke sejane u sudovima su košene četiri puta i meren je prinos suve materije (SM) svakog otkosa. Broj bakterija, plesni, amonifikatora, Azotobacter sp. i aktinomiceta je utvrđen na početku ogleda i nakon svakog košenja. U istraživanja su uključena dva kontrolna tretmana (zemljište bez đubriva i zemljište sa dodatim mineralnim đubrivom - KAN). Primena klinoptilolita obogaćenog sa amonijakom je pozitivno i značajno uticala na mikrobiološku aktivnost i povećala je prinos (od 4,9 g po sudu kod tretmana sa klinoptilolitom obogaćenim amonijakom do 4,3 g po sudu u zemljištu sa zemljištem i zeolitom zajedno). Naša istraživanja sugerišu da se može preporučiti dodavanje klinoptilolita organskim đubrivima (stajnjaku, kompostu). Ključna dobit od primene klinoptilolita bi se ogledala u povećanju zastupljenosti mikrobioloških zajednica i njihove aktivnosti.