UK PubMed Central (United Kingdom)

Poplar (Populus tremula × alba) lignins with exceedingly high syringyl monomer levels are produced by overexpression of the ferulate 5-hydroxylase (F5H) gene...Full Text Available

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Short rotation trials using cuttings poplar (Populus x rasumowskyana) in Southern Finland investigated the establishment of poplar plantations and the effects of spacing and application of nitrogen fertilizer on biomass production over a period of 6 years. Thicker cuttings grew better whilst those of less than 1 cm diameter grew only moderately. Nitrogen fertilization improved height and diameter growth and above-ground dry mass yield. Woody biomass production was 4.2 dry tons/ha per year, at 300 kg/ha nitrogen. A spacing of 15 000 stems/ha gave the best yield after 4 years, but 5000 stems/ha was more productive spacing in the next 2 years. (author).

Energy Technology Data Exchange (ETDEWEB)

The Bioenergy Feedstock Development Program, Environmental Sciences Division, Oak Ridge National Laboratory is developing poplars (Populus species and hybrids) as sources of renewable energy, i.e., ethanol. Notable increases in adaptability, volume productivity, and pest/stress resistance have been achieved via classical selection and breeding and intensified cultural practices. Significant advances have also been made in the efficiencies of harvesting and handling systems. Given these and anticipated accomplishments, program leaders are considering shifting some attention to genetically modifying feedstock physical and chemical properties, so as to improve the efficiency with which feedstocks can be converted to ethanol. This report provides an in-depth review and synthesis of opportunities for and feasibilities of genetically modifying feedstock qualities via classical selection and breeding, marker-aided selection and breeding, and genetic ...

UK PubMed Central (United Kingdom)

Background and AimsPopulus alba is a thermophilic forest tree present in the Mediterranean basin. Its habitat is highly fragmented and its distribution range has...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Short communication. 4 refs.

Energy Technology Data Exchange (ETDEWEB)

Poplar breeding in Europe is in a more advanced state than breeding programmes of other species. In Europe, poplars are part of the scenery and are integrated in the economy. Traditionally poplar stands are established in lowland areas. But an increasing interest in their use moved them to upland sites. Poplar uses are multiple: lumber, industrial wood, wind-breaks and landscape plantations, etc. Selection characteristics are classified in different groups: vegetative propagation ability, vigor, adaptation to sites and climate, resistance to diseases and insect pests, wood quality, and coppicing ability. Strategies have improved with time. The most efficient strategies for the long term involve constitution of base populations, selection of parents for intra- and interspecific hybridizations, selection within the progenies, and vegetative propagation. Short term strategies are also applied ...

UK PubMed Central (United Kingdom)

The level of indole-3-acetic acid (IAA) was locally modified in cambial tissues of transgenic aspen (Populus tremula L. × Populus tremuloides Michx.). We also...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Production costs for commercial-sized Populus plantations were developed from a series of research programs sponsored by the US Department of Energy's Short Rotation Woody Crops Program. Populus hybrid planted on good quality agricultural sites at a density of 2100 cuttings ha{sup {minus}1} was projected to yield an average of 16 Mg (OD) ha{sup {minus}1}yr{sup {minus}1}. Discounted cash flow analysis of multiple rotations showed pre-harvest production costs of $17 (US) Mg{sup {minus}1}(OD). 19 refs., 1 fig., 3 tabs.

UK PubMed Central (United Kingdom)

Vulnerability to xylem embolism by freeze-thaw cycles and water stress was quantified in ring-porous (Quercus gambelii Nutt.), diffuse-porous (Populus tremuloides Michx.,...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

A new stem taper function was established for individual trees of two poplar hybrid clones grown on a short-rotation coppice. The model could be easily fitted and required three parameters to be estimated. It can be used to estimate both diameter at a given height and height for a given top diameter. Two of the three parameters controlled the conical and the neiloid parts of the stem. Significant differences in these parameters were observed between the two clones even if no differences were observed for diameter at breast height or total height of the stem. The model could not be integrated to calculate volumes (total volume, merchantable volume), which were estimated by numerical integration. However, use of this new model allows the optimal length of billets to be determined and thus maximizes the merchantable biomass of poplar in short-rotation coppice by minimizing the biomass of residues.

Energy Technology Data Exchange (ETDEWEB)

The experiment was carried out on a short rotation coppice culture of poplars (POP-EUROFACE, Central Italy), growing in a free air carbon dioxide enriched atmosphere (FACE). The specific objective of this work was to study whether elevated CO{sub 2} and fertilization (two CO{sub 2} treatments, elevated CO{sub 2} and control, two N fertilization treatments, fertilized and unfertilized), as well as the interaction between treatments caused an unbalanced nutritional status of leaves in three poplar species (P. x euramericana, P. nigra and P. alba). Finally, we discuss the ecological implications of a possible change in foliar nutrients concentration. CO{sub 2} enrichment reduced foliar nitrogen and increased the concentration of magnesium; whereas nitrogen fertilization had opposite effects on leaf nitrogen and magnesium concentrations. Moreover, the interaction between elevated CO{sub 2} and N fertilization amplified some element unbalances such ...

International Nuclear Information System (INIS)

The possible contribution of short rotation cultures (SRC) to carbon sequestration in both current and elevated carbon dioxide concentrations was investigated using the free-air carbon dioxide enrichment (FACE) technique. Three poplar species were grown in an SRC plantation for three growing seasons. Above-ground and below-ground biomass increased by 15 to 27 per cent and by 22 to 38 per cent, respectively; light-efficiency also increased as a result. Depletion of inorganic nitrogen from the soil increased after three growing seasons at elevated carbon dioxide levels, but carbon dioxide showed no effect on stem wood density. Stem wood density also differed significantly from species to species. These results confirmed inter-specific differences in biomass production in poplar, and demonstrated that elevated carbon dioxide enhanced biomass productivity and light-use efficiency of a poplar short rotation cultivation ecosystem ...

Energy Technology Data Exchange (ETDEWEB)

In May 1985, a National Pollutant Discharge Elimination System permit was issued for the Oak Ridge Y-12 Plant, a nuclear weapons components production facility located in Oak Ridge, Tennessee, and operated by Martin Marietta Energy Systems, Inc., for the US Department of Energy. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Oak Ridge Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek), in particular, the growth and propagation of fish and aquatic life, as designated by the Tennessee Department of Health and Environment. A second purpose for the BMAP is to document the ecological effects resulting from implementation of a water pollution control program that will include construction of nine new wastewater treatment facilities over the next 4 years. Because of the complex nature of the effluent discharged to East ...

Energy Technology Data Exchange (ETDEWEB)

Propagation costs could be cut by replacing part of the micropropagation process with steps involving more traditional techniques. This study explored possibilities for improving existing vegetative propagation techniques for aspen using stem cuttings obtained from micropropagated plants. Vegetative propagation through stem cuttings was studied in 10 micropropagated hybrid aspen clones (Populus tremula L. x P. tremuloides Michx). Cuttings containing one axillary bud were harvested from the same donor plants twice during the growing season: the first harvest in May and the second harvest in July. Rooting percentage was correlated positively with root length, number of roots and height of cutting plant but negatively with length of rooting. The average rooting percentage was 53% in the first harvest and 27% in second harvest. Indole-3-butyric acid treatments (1.2 mM) significantly improved rooting in the second harvest, but not in the first harvest, suggesting ...

Science.gov (United States)

Sulfur dioxide emissions from an iron ore sintering plant have severely damaged vegetation up to 16 km northeast of the source. Concentric zones of increasing vegetation loss have formed around the point of maximum ground level concentration of the gas. Species diversity, sulfur and heavy metal concentrations in vegetation and soil amount to SO/sub 2/ injury were measured along a transect through the injury zones. Surrounding a central denuded area were zones dominated respectively by tussock-forming hair grass (Deschampsia flexuosa); low-growing shrubs and trailers (Sambucus pubens, Polygonum cilinode); higher-growing shrubs and suckering Populus tremuloides and Betula papyrifera) stunted forest tree species (Populus, Betula, Picea glauca, Abies Balsamea), and finally, normal boreal forest flora. Although SO/sub 2/ injury is continuing in this area, these zones now appear to be maintained primarily by severe erosion and destruction of suitable ...

International Nuclear Information System (INIS)

In this article the results of a study on sustainability of energy crops are discussed. Contribution to the reduction of the greenhouse effect and other environmental effects were investigated for the Netherlands. The study assumed that energy crops are grown on set-aside land or grain land. Generating electricity and/or heat from hemp, reed, miscanthus, poplar and willow show the best prospects. These crops are sustainable and may in the future be economically feasible. Ethanol from winter wheat shows the most favourable environmental effects, but is not economically efficient. Liquid fuels from oil seed rape and sugar beet are not very sustainable. 2 tabs., 4 refs.

Energy Technology Data Exchange (ETDEWEB)

Growth dynamics and biomass production in short-rotation poplar plantations were evaluated at Hanyuan Forestry Farm, Baoying County, P.R.C. Experimental treatments applied in a split-plot design included: four planting densities (1111, 833, 625 and 500 stems ha{sup -1}); three poplar clones (NL-80351, I-69 and I-72) and three rotation lengths. Survival of all three clones was excellent at the experimental site under the imposed management regime. Differences in DBH, height, LAI and above-ground biomass production, however, were manifested among the treatments. Overall the clonal ranking was in the order NL-80351 {>=}I-69 > I-72 by age 6. LAI values ranged from 0.6 to 4.4 m{sup 2} m{sup -2} and differences among four planting densities and three clones were significant throughout the first six years. Above-ground biomass productivity was affected considerably by planting density, clone and rotation length. Within the four ...

Energy Technology Data Exchange (ETDEWEB)

Canadian-based Anderson Group Company has developed an innovative round baler for harvesting a large variety of woody biomass. The baler was initially developed in 2005 in collaboration with the University Laval and Agriculture and Agri-Food Canada. The third generation BIOBALER{sup TM} is currently built, engineered and commercialized by Anderson. It can produce up to 40 bales/hr in short rotations woody crops such as willow and hybrid poplar. The unit can harvest brushes up to 125 mm in diameter. A standard tractor can pull the BIOBALER in fallow or abandoned land, under power transmission lines, and between planted trees. The patented BIOBALER includes a mulcher head attachment, a choice of long or short swivel tongue, a fixed chamber and an undercarriage frame.

Energy Technology Data Exchange (ETDEWEB)

Lower East Fork Poplar Creek (LEFPC) and its floodplain are contaminated with mercury (Hg) from ongoing and historical releases from the US Department of Energy (DOE) Oak Ridge Y-12 Plant. A remedial investigation and feasibility study of LEFPC resulted in the signing of a Record of Decision (ROD) in August 1995. In response to the ROD, soil contaminated with mercury above 400 mg/kg was removed from two sites in LEFPC and the floodplain during a recently completed remedial action (RA). The Postremediation Monitoring Program (PMP) outlined in the LEFPC Monitoring Plan was envisioned to occur in two phases: (1) a baseline assessment prior to remediation and (2) postremediation monitoring. The current report summarizes the results of the baseline assessment of soil, water, biota, and groundwater usage in LEFPC and its floodplain conducted in 1995 and 1996 by personnel of the Oak Ridge National Laboratory Biological Monitoring and Abatement Program (BMAP). This report ...

Energy Technology Data Exchange (ETDEWEB)

This study presents and applies a coherent methodological framework to compare biomass cascading chains, i.e. the subsequent use of biomass for materials, recycling and energy recovery, considering land use, CO2 emission reduction and economic performance. Example cascading chains of short rotation poplar wood are compared with each other on the basis of literature data. Results for these chains vary strongly, namely, from CO2 mitigation benefits of 200 euro/Mg CO2 to CO2 mitigation costs of 2200 euro/Mg CO2, and from net CO2 emission reductions per hectare of biomass production of 28 Mg CO2/(ha yr) to net CO2 emissions of 8 Mg CO2/(ha yr). Using a present-value approach to determine CO2 emissions and costs affects the performance of long-term cascading chains significantly, i.e. cost and CO2 emission reduction are decreased. In general, cascading has the potential to improve both CO2 emission reduction per hectare and CO2 mitigation costs of biomass usage. ...

Energy Technology Data Exchange (ETDEWEB)

The automotive paints could be generally differentiated by color, layer sequence and chemistry of the paint layers comprising each of the topcoat and the primer system. The successful identification of hit-and-run a and traffic accidental vehicles from evidential paint fragments is greatly facilitated with a comprehensive laboratory collection of reference paint samples and the technique for direct analysis without sample preparation. The Pyrolysis-Gas Chromatography(PGC) is a precise and reliable method for performing both quantitative and qualitative analysis of polymeric materials and forensic samples. Our Forensic Laboratory is conducting the examination and identification of 73 reference paint samples; 4 colors of each domestic automotive make that is poplar in Korea, by Curie Point Pyrolyzer(JHP-3) and GC with capillary column(ultra alloy-5). This method can be used not only to compare paint traces with their suspected sources, but also to identify the type, ...

Energy Technology Data Exchange (ETDEWEB)

Results are presented of trials in W. Germany involving Populus tremula X P. tremuloides. In a nursery in late August - early September 1971, some 1300 buds from 38 selected 3-yr-old hybrid aspen seedlings were grafted into T-slits at nodes 10-20 cm above root' collars of 1 and a half yr-old hybrid aspen stock (products of controlled crossings, and in some cases of similar parentage to the transplanted buds). In spring 1972, each stock (from which its own buds were removed) was cut back to a 'peg' 15-20 cm above the level of the graft; the 'peg' was later used to support the new shoot developed from the transplanted bud. By Sept. 1972, 33% of grafts were successful, the success rate being significantly different (3-67%) within clones; average height of scion shoots ranged from 79 to 375 cm (no significant difference between clones). In spring 1973, some 190 grafts from 35 clones were row-planted in the open (3 m between ...

Energy Technology Data Exchange (ETDEWEB)

The overall purpose of this project is to evaluate the biological and economic feasibility of restoring high-quality forests on mined land, and to measure carbon sequestration and wood production benefits that would be achieved from forest restoration procedures. In this quarterly report, we present a preliminary comparison of the carbon sequestration potential of forests growing on 14 mined sites in a seven-state region in the Midwestern and Eastern Coalfields. Carbon contents of these forests were compared to adjacent forests on non-mined land. The study was installed as a 3 x 3 factorial in a random complete block design with three replications at each location. The treatments include three forest types (white pine, hybrid poplar, mixed hardwood) and three silvicultural regimes (competition control, competition control plus tillage, competition control plus tillage plus fertilization). Each individual treatment plot is 0.5 acres. Each block of nine plots ...

Energy Technology Data Exchange (ETDEWEB)

The biobaler was originally developed for short-rotation willow plantations, but can currently harvest a wide range of woody crops with a basal diameter up to 150 mm. The biobaler is an alternate approach to harvest woody crops as round bales, generally 1.2 m wide by 1.5 m diameter. In addition to harvesting trees, it can improve management of wild brush, forest understory vegetation and encroaching small trees on abandoned land. It allows easy handling, storage and transportation to sites where the biomass can be used for energy use or other applications. This paper reported on a study that was conducted in the fall of 2009 in which a third generation biobaler was used on 8 different sites across Minnesota, notably Waseca, Madelia, Faribault, Afton, Ogilvie, Hinckley, Aurora and Hibbing. A total of 160 bales were harvested from these sites. The average bale mass was 466 kg and average bale density was 296 kg/m{sup 3}. The moisture content averaged 44.9 per cent and the bale dry matter ...

Energy Technology Data Exchange (ETDEWEB)

The initial development of additives to stabilize the viscosity of biocrude during long-term storage has produced dramatic results. The additives investigated were ethyl acetate, methyl isobuyl ketone and methanol, acetone, methanol, acetone and methanol, and ethanol. These additives represent three chemical families, which all demonstrated the ability to drastically reduce the aging rate of biocrude, as defined by the increase in viscosity with time. Accelerated aging tests were run at 90{degree}C to screen the additives. The additives not only lowered the initial viscosity at 40{degree}C by half but also reduced the aging rate of a hot gas filtered pyrolysis oil made from hybrid poplar (NREL run 175) by factors of 1-18 compared to the original pure oil. With the best additive, methanol, at a 10 wt% level in the pyrolysis oil, the modified biocrude was still a single-phase liquid and still met the ASTM no. 4 diesel fuel specification for viscosity even after 96 h ...

Energy Technology Data Exchange (ETDEWEB)

The central research question of this thesis is: What is the potential of multi-functional biomass systems to improve the costs and the land use efficiency of saving non-renewable energy consumption and reducing GHG (greenhouse gases) emissions in quantitative terms? Therefore, in the following chapters the performance of multi-functional biomass systems is quantified. Biomass system costs are investigated from a societal perspective using e.g. low discount rates. A main focus will be on the review of methodologies for accounting GHG emissions, non-renewable energy consumption, agricultural land use and costs as well as the adaptation of these methodologies to special aspects of multifunctional biomass use. The analysis of the potential benefits of multi-functional biomass systems is carried out by several case studies of biomass systems including various waste treatment technologies for the short term that appeared promising after a first review. Because at present the shift of ...