“…Their presence can cause disadvantageous changes in paper as it ages and is exposed to mould, high relative humidity, light, and pollution or/ and some conservation treatments (e.g., oxidative and reduction bleaching) (Leponiemi et al, 2010;Sridach, 2010;McKean et al, 1997). From all nutrients, Si is the most damaging element in the raw material for pulping, because it complicates the recovery of chemicals, wears out the installations of paper factories and can affect the paper quality (Saijonkari-Pahkala, 2001; Gonzalez et al, 2008;Sotannde et al, 2014 ). According to gained results of straw chemical composition analysis (Table 3), it could be concluded that barley straw contains the highest concentration of all analysed microelements.…”