Search results for " spruce"
showing 5 items of 15 documents
Statistical upscaling of ecosystem CO2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertainties
2021
The regional variability in tundra and boreal carbon dioxide (CO2) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990–2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to a…
Fast pyrolysis of hot-water-extracted and delignified Norway spruce (Picea abies) sawdust by Py-GC/MS
2019
The thermochemical behavior of Norway spruce (Picea abies) sawdust as such and after various chemical treatments (hot-water extraction, delignification, and hot-water extraction followed by delignification) was investigated by analytical pyrolysis–gas chromatography–mass spectrometry. In each case, the yields of major GC-amenable condensable products were semi-quantitatively measured, and the individual compounds were classified into several compound groups. The formation of these groups from feedstock samples with varying mass portions of their structural constituents (carbohydrates and lignin) was determined at 500 °C and 700 °C with a residence time of 5 s and 20 s. The formation of pyro…
Availability of extractives from various Norway spruce (Picea abies) stumps assortments
2022
Stumps and knotwood of Norway spruce (Picea abies) are valuable sources of wood extractives. Although lignans from knotwood have already been utilized in value-added products, the behavior and valorization of stump-derived extractives are less studied. In this study, the composition of lipophilic and hydrophilic extractives, particularly lignans, from various spruce stump samples (stump bottom, stump heart, and crushed stump samples) stored outside were studied. Lipophilic and hydrophilic extracts were separated with an accelerated solvent extraction (ASE) apparatus using n-hexane and hot water, respectively. The detailed extractives content of samples was then determined by gas chromatogra…
Analytical pyrolysis of wood and non-wood materials from integrated biorefinery concepts
2019
Wood and non-wood differ with respect to their anatomical, physical, and chemical properties, even among their species, resulting in different behaviors during thermal conversion. Hence, understanding the degradation of these feedstocks by pyrolysis is attractive to establish biorefinery possibilities for renewable resources. Additionally, biomass pretreatment technology plays an important role in many biorefinery processes. Therefore, an approach that integrates such pretreatment with pyrolysis offers an attractive, novel method for improving the end-product spectrum (e.g., enriched either with aliphatic or aromatic constituents). Furthermore, a rapid analytical method for biomass feedstoc…
Survival, Growth and Mycorrhization of Containerised Pinus sylvestris and Picea abies Seedlings of Different Provenances Outplanted in a Forest Clear…
2017
Abstract We studied field performance of containerised Pinus sylvestris and Picea abies seedlings of different provenances. Shoot height, needle chemical composition, root collar diameter, root mycorrhization and mycorrhizal species composition were evaluated after four growing seasons following outplanting. The results showed that in general spruce had better survival than pine. Ectomycorrhizas on spruce were dominated by Wilcoxina, Amphinema and Tylospora, while on pine — by Suillus and Thelephora species. Spruce and pine showing best growth rates were colonised by ectomycorrhizal fungus Amphinema sp. In conclusion, the results demonstrated that forest nursery practices as well as provena…