Spatial distribution of Si in Pinus Insigne (Pinus radiata) Wood using micro XRF by Synchrotron Radiation

Abstract

Silicon, while not an essential element, is known to have positive roles in certain vegetable species. For instance, it has been recognized to protect them from biotic and abiotic stress. Due to the fact that certain species accumulate the aforementioned element in their tissues, the determination of its concentration is of importance in different disciplines, such as dendrology, plant physiology, forest management, agroecology, and also in the wood industry. Usually, its quantification is preceded by a series of digestion steps that, aside from been time-consuming, and contamination-prone, prevents from conducting a spatial distribution of the element on the sample. In this research, samples of Pinus radiata wood were studied using a synchrotron radiation source that allowed direct scanning of its surface without any treatment, and the determination of silicon as a function of the position and the tree rings, using micro X-ray fluorescence (µXRF). A quantification method based in the fundamental parameters approach was evaluated. It was found that silicon concentration increases near the latewood ring zones, showing a periodical behavior, related to seasonal environmental events.