Studies on the content and distribution of mineral substances including calcium (Ca), potassium (K), magnesium (Mg), manganese (Mn), iron (Fe), sodium (Na), zinc (Zn), aluminum (Al), lead (Pb) and strontium (Sr) were performed. Samples of Scots pine were gained from stems with Ist degradation degree of tree (considered to grow in the area with weak environmental pollution), IInd degradation degree (strong pollution) and IIIrd degradation degree (very strong pollution). Nitrogen industrial plant was acknowledged as the source of pollution. Samples were collected from butt-end, middle- and top sections of the stem in following zones: sapwood, heartwood adjacent sapwood, heartwood and bark. Results indicate that nitrogen industrial plant causes the decrease of mineral substances content in bark from butt-end section of stems with IInd and IIIrd degradation degree in relation to stems with Ist degradation degree. Calcium content is the highest in heartwood and decreases in the direction to stem perimeter, regardless of stem section and environmental pollution degree. Very strong pollution decreases potassium content in wood in comparison to samples collected in areas with strong and weak pollution. Environmental pollution also decreases sodium content in wood, and increases content of manganese, aluminum, lead and strontium.
Chosen metals contents were analyzed in Norway maple (Acer platanoides L.) in bark, roots and wood samples collected from the polluted environment. Samples were gained from three cca. 40-year old trunks, which were grown on Krakowskie Przedmieście st., next to the St. Anna church in Warsaw, Poland. Wood of trunk and the main roots, as well as bark from butt-end section were also sampled. Contents of Ca, Mg, Mn, Zn, Fe, Al, K, Na and Sr were examined with the application of spectrometric methods. The results show that environmental pollution significantly influences the content of examined elements. The change of Na content is the most spectacular. Its content is hundred times higher, in wood and bark, as well as in the main roots, in relation tree from non-polluted environment, what is probably caused by urban environment salinity.
The concentration of selected heavy metals: chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu) and zinc (Zn) in 5-year-old wood of Populus trichocarpa before and after steam explosion (SE) and liquid hot water (LHW) pretreatments was studied. The concentration of the above heavy metals in the liquid fraction obtained after pretreatments was also studied. The studied problem of heavy metals in lignocellulosic biomass is an interesting and important issue in the context of bioethanol production technology. An X-ray fluorescence spectrometer (XRF) was used to analyse the concentration of heavy metals. The change of concentration of the tested elements in wood biomass after pretreatment was small (except for iron). On the other hand, the average concentration of iron in wood biomass of a 5-year-old Populus trichocarpa, after SE and LHW with duration of the pretreatments 15 and 60 min, increased about 24-fold to 28-fold, comparing to its average concentration in native wood. During the pretreatment process, wood biomass absorbed the iron that at high temperatures passed from the pretreatment equipment to the solution. The average concentration of the elements under research in liquid fraction obtained during SE and LHW of wood biomass with duration of the pretreatments 15 and 60 min was at a low level.
The pine stems were cut from three different polluted environments – Ist trees degradation degree (weak pollution), IInd trees degradation degree (strong pollution) and IIIrd trees degradation degree (connected with very strong pollution). On the basis of obtained results it was stated that environmental pollution caused changes in late wood participation, as well as distribution of cellulose on the stem cross- and longitudinal section. It also changed cellulose content in bark from the butt-end section, which was about 26% regardless the degradation degree. The environmental pollution caused also an increase of viscometric average polymerization degree of cellulose in heartwood in relation to heartwood adjacent sapwood and sapwood from butt-end section. Regardless the degradation degree, cellulose polymerization degree in heartwood adjacent sapwood from the middle part of the stem was higher in comparison to sapwood and heartwood. Moreover, the environmental pollution caused the increase of viscometric average polymerization degree of cellulose in bark. The polymerization degree of cellulose in bark from the butt-end section of IIIrd degradation degree stems was 22% and 23% higher in comparison to the Ist and IInd degradation degree.