Search results for "Biomas"
showing 10 items of 980 documents
Salmu granulu ražošanas uzņēmuma izveide Siguldas novadā
2020
Maģistra darbā “Salmu granulu ražošanas uzņēmuma izveide Siguldas novadā” tiek izstrādāts projekts uzņēmējdarbības uzsākšanai ar mērķi veicināt biomasas nozares attīstību Latvijā. Maģistra darbā tiek veikta kurināmās biomasas attīstības analīze un piedāvāts risinājums salmu granulu ražošanas uzsākšanas iespējai, kā alternatīvu malkai, lai samazinātu mežu izciršanu un koksnes patēriņu apkures vajadzībām. Problēmas risināšanai tiek veikts pētījums par biomasas attīstības tendencēm, un veikta privātmāju īpašnieku aptauja par kurināmā izvēles paradumiem. Darbs sastāv no 81 lappusēm, 22 attēliem, 10 tabulām un 21 pielikumiem. Atslēgas vārdi: projekta vadīšana, biomasa, salmu granulas.
First Retrievals of ASCAT-IB VOD (Vegetation Optical Depth) at Global Scale
2021
Global and long-term vegetation optical depth (VOD) dataset are very useful to monitor the dynamics of the vegetation features, climate and environmental changes. In this study, the radar-based global ASCAT (Advanced SCATterometer) IB (INRAE-BORDEAUX) VOD was retrieved using a model which was recently calibrated over Africa. In order to assess the performance of IB VOD, the Saatchi biomass and three other VOD datasets (ASCAT V16, AMSR2 LPRM V5 and VODCA LPRM V6) derived from C-band observations were used in the comparison. The preliminary results show that IB VOD has a promising ability to predict biomass $(\mathrm{R}=0.74,\ \text{RMSE} =44.82\ \text{Mg}\ \text{ha}^{-1})$ , which is better …
Lead concentrations in feathers and blood of common blackbirds (Turdus merula) and in earthworms inhabiting unpolluted and moderately polluted urban …
2006
9 pages; International audience; Despite the dramatic decrease of atmospheric lead (Pb) concentrations in urban areas of most industrialised countries, we hypothesised that urban common blackbirds (Turdus merula) may still be contaminated by Pb concentrations of toxicological concern due to transfer from soil through the food chain. We sampled blackbirds and earthworms, one of their main preys, in Besan?, a middle-size city of Eastern France (where atmospheric Pb concentrations decreased from 0.5 microg/m(3) in 1987 to nearly 0 in 2002) and in a rural reference site. Lead concentrations were determined in the tissues of the different functional groups of earthworms (anecic, epigeous and end…
Emerging techniques in bioethanol production: from distillation to waste valorization
2019
Ethanol production from biomass, especially waste biomass, and the use of such ethanol as fuel can reduce fossil fuel consumption and ameliorate the hidden costs of burning fossil fuels such as its environmental impact. However, bioethanol production suffers from several limitations such as being energy-intensive and generating a sizeable amount of waste. This review briefly describes the aspects related to bioethanol production and focuses on both theoretical and practical approaches for process improvements. Several green emerging distillation techniques, such as ohmic-assisted hydrodistillation, membrane-assisted distillation, and heat integrated techniques, are shown to be energy-saving…
From wood pellets to wood chips, risks of degradation and emissions from the storage of woody biomass – A short review
2016
Abstract The compounds in stored woody biomass degrade as a result of chemical and/or biological processes during storage. These processes produce gaseous emissions. Recent studies concerning gaseous emissions from wood pellet storages are reviewed herein. The applicability of the results from pellet research to wood chips is discussed. Thorough scientific understanding on the storage phenomena of wood chips is extremely important as the threat of climate change and the need to reduce greenhouse gas emissions have led to an increased need to large scale wood chip storage to ensure supply. Typically the gases produced from stored woody biomasses are carbon monoxide (CO), carbon dioxide (CO 2…
Measurement methodology for greenhouse gas emissions from storage of forest chips–A review
2015
Abstract Research on greenhouse gas emission related to solid biofuels has focused mainly on the emissions from end use and the production chain. GHG emissions from the storage of forest chips have not received much attention in recent literature. In order for EU emission reduction targets to be fully understood, emissions from solid biofuel storage needs to be better described. Usually emissions from chip piles have been modelled using studies from organic waste composting but these two materials can differ appreciably; for example the C/N-ratio and moisture content. Herein, previous studies on greenhouse gas emissions from forest chips piles during storage are reviewed. The objective is t…
Sustainable Energy Supply Based on Sunflower Seed Husk for Oil mills
2019
The use of biomass, including sunflower husk, for in-situ energy generation has undergone a development in Ukraine last decades. Within this work, four combined heat and power technologies based on oil utilization, husk combustion, gasification, and methanization have been investigated. Their electricity and heat potential has been determined. Criteria for techno-economical assessment of CHP technologies have been suggested. Husk biogas and gasification technologies are not mature. CHP plants based on husk combustion are competitive. Steam turbine generators with a nominal electric capacity higher 1.5 MW may be profitable too.
Spatial models for monitoring the spatio-temporal evolution of ashes after fire-a case study of a burnt grassland in Lithuania
2013
Ash thickness is a key variable in the protection of soil against erosion agents after planned and unplanned fires. Ash thickness measurements were conducted along two transects (flat and sloping areas) following a grided experimental design. In order to interpolate data with accuracy and identify the techniques with the least bias, several interpolation methods were tested in the grided plot. Overall, the fire had a low severity. However, the fire significantly reduced the ground cover, especially on sloping areas, owing to the higher fire severity and/or less biomass previous to the fire. Ash thickness depended on fire severity and was thin where fire severity was higher and thicker in lo…
Spatial distribution of phytoplankton and picocyanobacteria in Lake Tanganyika in March and April 1998
2003
The spatial distribution of phytoplankton and picocyanobacteria was studied in Lake Tanganyika in relation to environmental factors. Sampling was conducted within three weeks during the wet season of 1998 when the water column stratification was most stable. The secchi depth varied between 11 and 16 m, except off the river Malagarasi (3 m). The depth of the euphotic zone was 33 to 56 m. Altogether, 218 phytoplankton taxa were identified. Their total biomass varied between 13 and 88 mg m−3 fresh weight. Picocyanobacteria were present at very high densities (104 to 6 × 10 5 cells ml−1). The influence of the river Malagarasi appeared to spread along the water surface because of the lower densi…
Cross-hemispheric transport of central African biomass burning pollutants: implications for downwind ozone production
2010
Pollutant plumes with enhanced concentrations of trace gases and aerosols were observed over the southern coast of West Africa during August 2006 as part of the AMMA wet season field campaign. Plumes were observed both in the mid and upper troposphere. In this study we examined the origin of these pollutant plumes, and their potential to photochemically produce ozone (O<sub>3</sub>) downwind over the Atlantic Ocean. Their possible contribution to the Atlantic O<sub>3</sub> maximum is also discussed. Runs using the BOLAM mesoscale model including biomass burning carbon monoxide (CO) tracers were used to confirm an origin from central African biomass burning fires. The…