Potential bioethanol and biogas production using lignocellulosic biomass from winter rye, oilseed rape and faba bean

To meet the increasing need for bioenergy several raw materials have to be considered for the production of e.g. bioethanol and biogas.In this study, three lignocellulosic raw materials were studied, i.e. (1) winter rye straw (Secale cereale L), (2) oilseed rape straw (Brassica napus L.) and (3) faba bean straw (Viciafaba L.). Their composition with regard to cellulose, hemicellulose, lignin, extractives and ash was evaluated, as well as their potential as raw materials for ethanol and biogas production. The materials were pretreated by wet oxidation using parameters previously found to be optimal for pretreatment of corn stover (195 1C, 15 min, 2 g l_1 Na2CO3 and 12 bar oxygen). It was shown that pretreatment was necessary for ethanol production from all raw materials and gave increased biogas yield from winter rye straw. Neither biogas productivity nor yield from oilseed rape straw or faba bean straw was significantly affected by pretreatment. Ethanol was produced by the yeast Saccharomyces cerevisiae during simultaneous enzymatic hydrolysis of the solid material after wet oxidation with yields of 66%, 70% and 52% of theoretical for winter rye, oilseed rape and faba bean straw, respectively. Methane was produced with yields of 0.36, 0.42 and 0.44 l g_1 volatile solids for winter rye, oilseed rape and faba bean straw, respectively, without pretreatment of the materials. However, biogas productivity was low and it took over 50 days to reach the final yield. It could be concluded that all three materials are possible raw materials for either biogas or ethanol production; however, improvement of biogas productivity or ethanol yield is necessary before an economical process can be achieved. 2007 Elsevier Ltd. All rights reserved

Närhet och fredagsmys : Familjens betydelse för ungdomar

The aim of this study was to examine how young people define their family and how they describe their own family relations. What makes the family a family from the perspective of a youth? The questions posed were: Who do you include in your family? and What makes family important?. Utilizing a qualitative method known as self-documentary data compilation, young people, aged 15, have written essays to answer the questions in focus. Selection was based on voluntary participation at three public schools in Malmö, Sweden. The background for this study was a 1 year master’s thesis presented in 1995. The study directed attention toward a massmedial discussion during the mid-1990´s focusing parental withdrawal from the guidance of young people, leaving the family arena open for peer regulation. The conclusions from the 1995 study contradicted media reports. The family was highly respected and deemed beneficial to participant young people. Further, no difference could be shown relating to such factors as socioeconomic standard or gender. The current study replicates the 1995 study, representing a period 15 years later In focus was whether youth have changed in their way to define the family. The result shows that young people today tend to be more open-minded as to whom they include when defining the family. Conventional family members, such as siblings, may be excluded from the core group. Important today is constancy; that those who belong to the family, whether relative or not, are unceasingly available. Young people also seem to be aware of their decision-making capacity regarding curfews, clothing choices, etc. The subject is complex and there remains more to discover

Green house gas (GHG) emissions from Danish bioethanol production and choice of biomass raw materials

It is very much debated whether bioethanol is a sustainable energy resource that can offer environmental and long-term economic advantages over fossil fuels, like gasoline or die-sel. From the present first generation bioethanol technology focusing on starch (from grain) fermentation GHG savings are only modest. The Danish Integrated Biomass Utili-sation System (IBUS) has developed both first generation and second generation princi-pal bioethanol technologies characterised by integration with an existing coal-fired Com-bined Heat and Power (CBH) plant. To secure that bioenergy is produced from local adapted raw materials with limited use of non-renewable fossil fuels there is a need for integrating the biomass starting point into the energy manufacturing steps. Substitution of fossil fuels by crop biomass requires the right selection of plant species according not only to chemical quality for efficient con-version but also to secure the development of ecologically benign farming system includ-ing biomass for energy. The aim of the present study was to question how to optimise GHG savings for bioetha-nol production using the IBUS technology

Pollen-Based Maps of Past Regional Vegetation Cover in Europe Over 12 Millennia-Evaluation and Potential

Realistic and accurate reconstructions of past vegetation cover are necessary to study past environmental changes. This is important since the effects of human land-use changes (e.g. agriculture, deforestation and afforestation/reforestation) on biodiversity and climate are still under debate. Over the last decade, development, validation, and application of pollen-vegetation relationship models have made it possible to estimate plant abundance from fossil pollen data at both local and regional scales. In particular, the REVEALS model has been applied to produce datasets of past regional plant cover at 1 degrees spatial resolution at large subcontinental scales (North America, Europe, and China). However, such reconstructions are spatially discontinuous due to the discrete and irregular geographical distribution of sites (lakes and peat bogs) from which fossil pollen records have been produced. Therefore, spatial statistical models have been developed to create continuous maps of past plant cover using the REVEALS-based land cover estimates. In this paper, we present the first continuous time series of spatially complete maps of past plant cover across Europe during the Holocene (25 time windows covering the period from 11.7 k BP to present). We use a spatial-statistical model for compositional data to interpolate REVEALS-based estimates of three major land-cover types (LCTs), i.e., evergreen trees, summer-green trees and open land (grasses, herbs and low shrubs); producing spatially complete maps of the past coverage of these three LCTs. The spatial model uses four auxiliary data sets-latitude, longitude, elevation, and independent scenarios of past anthropogenic land-cover change based on per-capita land-use estimates ("standard" KK10 scenarios)-to improve model performance for areas with complex topography or few observations. We evaluate the resulting reconstructions for selected time windows using present day maps from the European Forest Institute, cross validate, and compare the results with earlier pollen-based spatially-continuous estimates for five selected time windows, i.e., 100 BP-present, 350-100 BP, 700-350 BP, 3.2-2.7 k BP, and 6.2-5.7 k BP. The evaluations suggest that the statistical model provides robust spatial reconstructions. From the maps we observe the broad change in the land-cover of Europe from dominance of naturally open land and persisting remnants of continental ice in the Early Holocene to a high fraction of forest cover in the Mid Holocene, and anthropogenic deforestation in the Late Holocene. The temporal and spatial continuity is relevant for land-use, land-cover, and climate research

Pollen-Based Maps of Past Regional Vegetation Cover in Europe Over 12 Millennia-Evaluation and Potential

Realistic and accurate reconstructions of past vegetation cover are necessary to study past environmental changes. This is important since the effects of human land-use changes (e.g. agriculture, deforestation and afforestation/reforestation) on biodiversity and climate are still under debate. Over the last decade, development, validation, and application of pollen-vegetation relationship models have made it possible to estimate plant abundance from fossil pollen data at both local and regional scales. In particular, the REVEALS model has been applied to produce datasets of past regional plant cover at 1 degrees spatial resolution at large subcontinental scales (North America, Europe, and China). However, such reconstructions are spatially discontinuous due to the discrete and irregular geographical distribution of sites (lakes and peat bogs) from which fossil pollen records have been produced. Therefore, spatial statistical models have been developed to create continuous maps of past plant cover using the REVEALS-based land cover estimates. In this paper, we present the first continuous time series of spatially complete maps of past plant cover across Europe during the Holocene (25 time windows covering the period from 11.7 k BP to present). We use a spatial-statistical model for compositional data to interpolate REVEALS-based estimates of three major land-cover types (LCTs), i.e., evergreen trees, summer-green trees and open land (grasses, herbs and low shrubs); producing spatially complete maps of the past coverage of these three LCTs. The spatial model uses four auxiliary data sets-latitude, longitude, elevation, and independent scenarios of past anthropogenic land-cover change based on per-capita land-use estimates ("standard" KK10 scenarios)-to improve model performance for areas with complex topography or few observations. We evaluate the resulting reconstructions for selected time windows using present day maps from the European Forest Institute, cross validate, and compare the results with earlier pollen-based spatially-continuous estimates for five selected time windows, i.e., 100 BP-present, 350-100 BP, 700-350 BP, 3.2-2.7 k BP, and 6.2-5.7 k BP. The evaluations suggest that the statistical model provides robust spatial reconstructions. From the maps we observe the broad change in the land-cover of Europe from dominance of naturally open land and persisting remnants of continental ice in the Early Holocene to a high fraction of forest cover in the Mid Holocene, and anthropogenic deforestation in the Late Holocene. The temporal and spatial continuity is relevant for land-use, land-cover, and climate research

Mid-Holocene European climate revisited: New high-resolution regional climate model simulations using pollen-based land-cover

Land-cover changes have a clear impact on local climates via biophysical effects. European land cover has been affected by human activities for at least 6000 years, but possibly longer. It is thus highly probable that humans altered climate before the industrial revolution (AD1750-1850). In this study, climate and vegetation 6000 years (6 ka) ago is investigated using one global climate model, two regional climate models, one dynamical vegetation model, pollen-based reconstruction of past vegetation cover using a model of the pollen-vegetation relationship and a statistical model for spatial interpolation of the reconstructed land cover. This approach enables us to study 6 ka climate with potential natural and reconstructed land cover, and to determine how differences in land cover impact upon simulated climate. The use of two regional climate models enables us to discuss the robustness of the results. This is the first experiment with two regional climate models of simulated palaeo-climate based on regional climate models.Different estimates of 6 ka vegetation are constructed: simulated potential vegetation and reconstructed vegetation. Potential vegetation is the natural climate-induced vegetation as simulated by a dynamical vegetation model driven by climate conditions from a climate model. Bayesian spatial model interpolated point estimates of pollen-based plant abundances combined with estimates of climate-induced potential un-vegetated land cover were used for reconstructed vegetation. The simulated potential vegetation is heavily dominated by forests: evergreen coniferous forests dominate in northern and eastern Europe, while deciduous broadleaved forests dominate central and western Europe. In contrast, the reconstructed vegetation cover has a large component of open land in most of Europe.The simulated 6 ka climate using reconstructed vegetation was 0-5 degrees C warmer than the pre-industrial (PI) climate, depending on season and region. The largest differences are seen in north-eastern Europe in winter with about 4-6 degrees C, and the smallest differences (close to zero) in southwestern Europe in winter. The simulated 6 ka climate had 10-20% more precipitation than PI climate in northern Europe and 10-20% less precipitation in southern Europe in summer. The results are in reasonable agreement with proxy-based climate reconstructions and previous similar climate modelling studies. As expected, the global model and regional models indicate relatively similar climates albeit with regional differences indicating that, models response to land-cover changes differently.The results indicate that the anthropogenic land-cover changes, as given by the reconstructed vegetation, in this study are large enough to have a significant impact on climate. It is likely that anthropogenic impact on European climate via land-use change was already taking place at 6 ka. Our results suggest that anthropogenic land-cover changes at 6 ka lead to around 0.5 degrees C warmer in southern Europe in summer due to biogeophysical forcing. (C) 2022 The Authors. Published by Elsevier Ltd

Mid-Holocene European climate revisited: New high-resolution regional climate model simulations using pollen-based land-cover

Land-cover changes have a clear impact on local climates via biophysical effects. European land cover has been affected by human activities for at least 6000 years, but possibly longer. It is thus highly probable that humans altered climate before the industrial revolution (AD1750-1850). In this study, climate and vegetation 6000 years (6 ka) ago is investigated using one global climate model, two regional climate models, one dynamical vegetation model, pollen-based reconstruction of past vegetation cover using a model of the pollen-vegetation relationship and a statistical model for spatial interpolation of the reconstructed land cover. This approach enables us to study 6 ka climate with potential natural and reconstructed land cover, and to determine how differences in land cover impact upon simulated climate. The use of two regional climate models enables us to discuss the robustness of the results. This is the first experiment with two regional climate models of simulated palaeo-climate based on regional climate models.Different estimates of 6 ka vegetation are constructed: simulated potential vegetation and reconstructed vegetation. Potential vegetation is the natural climate-induced vegetation as simulated by a dynamical vegetation model driven by climate conditions from a climate model. Bayesian spatial model interpolated point estimates of pollen-based plant abundances combined with estimates of climate-induced potential un-vegetated land cover were used for reconstructed vegetation. The simulated potential vegetation is heavily dominated by forests: evergreen coniferous forests dominate in northern and eastern Europe, while deciduous broadleaved forests dominate central and western Europe. In contrast, the reconstructed vegetation cover has a large component of open land in most of Europe.The simulated 6 ka climate using reconstructed vegetation was 0-5 degrees C warmer than the pre-industrial (PI) climate, depending on season and region. The largest differences are seen in north-eastern Europe in winter with about 4-6 degrees C, and the smallest differences (close to zero) in southwestern Europe in winter. The simulated 6 ka climate had 10-20% more precipitation than PI climate in northern Europe and 10-20% less precipitation in southern Europe in summer. The results are in reasonable agreement with proxy-based climate reconstructions and previous similar climate modelling studies. As expected, the global model and regional models indicate relatively similar climates albeit with regional differences indicating that, models response to land-cover changes differently.The results indicate that the anthropogenic land-cover changes, as given by the reconstructed vegetation, in this study are large enough to have a significant impact on climate. It is likely that anthropogenic impact on European climate via land-use change was already taking place at 6 ka. Our results suggest that anthropogenic land-cover changes at 6 ka lead to around 0.5 degrees C warmer in southern Europe in summer due to biogeophysical forcing. (C) 2022 The Authors. Published by Elsevier Ltd

European pollen-based REVEALS land-cover reconstructions for the Holocene: methodology, mapping and potentials

Quantitative reconstructions of past land cover are necessary to determine the processes involved in climate-human-land-cover interactions. We present the first temporally continuous and most spatially extensive pollen-based land-cover reconstruction for Europe over the Holocene (last 11 700 cal yr BP). We describe how vegetation cover has been quantified from pollen records at a 1 degrees x 1 degrees spatial scale using the "Regional Estimates of VEgetation Abundance from Large Sites" (REVEALS) model. REVEALS calculates estimates of past regional vegetation cover in proportions or percentages. REVEALS has been applied to 1128 pollen records across Europe and part of the eastern Mediterranean-Black Sea-Caspian corridor (30-75 degrees N, 25 degrees W-50 degrees E) to reconstruct the percentage cover of 31 plant taxa assigned to 12 plant functional types (PFTs) and 3 land-cover types (LCTs). A new synthesis of relative pollen productivities (RPPs) for European plant taxa was performed for this reconstruction. It includes multiple RPP values (>= 2 values) for 39 taxa and single values for 15 taxa (total of 54 taxa). To illustrate this, we present distribution maps for five taxa (Calluna vulgaris, Cerealia type (t)., Picea abies, deciduous Quercus t. and evergreen Quercus t.) and three land-cover types (open land, OL; evergreen trees, ETs; and summer-green trees, STs) for eight selected time windows. The reliability of the REVEALS reconstructions and issues related to the interpretation of the results in terms of landscape openness and human-induced vegetation change are discussed. This is followed by a review of the current use of this reconstruction and its future potential utility and development. REVEALS data quality are primarily determined by pollen count data (pollen count and sample, pollen identification, and chronology) and site type and number (lake or bog, large or small, one site vs. multiple sites) used for REVEALS analysis (for each grid cell). A large number of sites with high-quality pollen count data will produce more reliable land-cover estimates with lower standard errors compared to a low number of sites with lower-quality pollen count data. The REVEALS data presented here can be downloaded from https://doi.org/10.1594/PANGAEA.937075 (Fyfe et al., 2022)