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A reduction in energetic and economic costs is key to the sustainable development of Short Rotation Coppices (SRC) for energy purposes. During their cultivation, the highest costs are incurred during the planting and harvesting phases. A new planting method, which involves the horizontal disposition of stems or cuttings 120 cm long, at a depth of 5–10 cm, could provide energy and cost savings during planting. The results of three experimental plots in Casale M. to (AL), one in Cannara (PG) and one in Chioggia (VE) are shown: horizontal stems and long cuttings were able to produce from 1 to 5 sprouts per meter (sp m −1 ), depending on the genotype and environmental conditions. Willow was able to produce on average from 2.1 to 4.8 sp m −1 and between poplars, the species P. ×canadensis produced more sprouts that Populus deltoides (3.9 sp m −1 compared with 1.9 sp m −1 ). Yields reached a maximum in a Casale M. to trial with 12.7 oven dry tons per hectare (Odt ha −1 ) for poplar ‘Orion’ and 12.3 Odt ha −1 for willow ‘Levante’ at the end of first year. The variability of sprouts production and growth of trees makes this method suitable for SRC or stool-beds. [ABSTRACT FROM AUTHOR]

Abstract: Eucalyptus plantations in the Southern United States offer a viable feedstock for renewable bioenergy. Delivered cost of eucalypt biomass to a bioenergy facility was simulated in order to understand how key variables affect biomass delivered cost. Three production rates (16.8, 22.4 and 28.0 Mg ha−1 y−1, dry weight basis) in two investment scenarios were compared in terms of financial analysis, to evaluate the effect of productivity and land investment on the financial indicators of the project. Delivered cost of biomass was simulated to range from $55.1 to $66.1 per delivered Mg (with freight distance of 48.3 km from plantation to biorefinery) depending on site productivity (without considering land investment) at 6% IRR. When land investment was included in the analysis, delivered biomass cost increased to range from $65.0 to $79.4 per delivered Mg depending on site productivity at 6% IRR. Conversion into cellulosic ethanol might be promising with biomass delivered cost lower than $66 Mg−1. These delivered costs and investment analysis show that Eucalyptus plantations are a potential biomass source for bioenergy production for Southern U.S. [ABSTRACT FROM AUTHOR]

Abstract: This case study has been carried out as a comparison between two different land-use strategies for climate change mitigation, with possible application within the Clean Development Mechanisms. The benefits of afforestation for carbon sequestration versus for bioenergy production are compared in the context of development planning to meet increasing domestic and agricultural demand for electricity in Hosahalli village, Karnataka, India. One option is to increase the local biomass based electricity generation, requiring an increased biomass plantation area. This option is compared with fossil based electricity generation where the area is instead used for producing wood for non-energy purposes while also sequestering carbon in the soil and standing biomass. The different options have been assessed using the PRO-COMAP model. The ranking of the different options varies depending on the system boundaries and time period. Results indicate that, in the short term (30 years) perspective, the mitigation potential of the long rotation plantation is largest, followed by the short rotation plantation delivering wood for energy. The bioenergy option is however preferred if a long-term view is taken. Short rotation forests delivering wood for short-lived non-energy products have the smallest mitigation potential, unless a large share of the wood products are used for energy purposes (replacing fossil fuels) after having served their initial purpose. If managed in a sustainable manner all of these strategies can contribute to the improvement of the social and environmental situation of the local community. [Copyright &y& Elsevier]

Above-ground biomass production was estimated for Gmelina arborea (Roxb) plantations (ages 5–21 years) in Oluwa Forest Reserve, Nigeria. A total of 120 trees were harvested and weighed to provide data for the estimation of biomass as well as for developing biomass equations. The results showed that Gmelina has high biomass yield, ranging from 83.2 t ha−1 (5 years) to 394.9 t ha−1 (21 years). Mean annual biomass increment varied from 16.2 to 20.9 t ha−1 yr−1. Average biomass allocations to different components of the tree were as follows: Stem about 84%; branch 13% and foliage 3%. The high biomass values were attributed to fast growth, high stand density (range: 837–1275 stems ha−1) and good site conditions in the study area. Biomass values of the various tree components (stem, branch and foliage) as well as total above-ground biomass (TAGB) were regressed with diameter at breast height (dbh) on the one hand (equation form 1), and with dbh and total height (in the form of D2H) on the other (equation form 2), with the aim of choosing the most suitable equation form. All equations generated had very high adjusted R2 and very low standard error of estimate. Residuals for both equation forms were normally and randomly distributed. Only little improvement in the ability of the equations to explain the variations in biomass was achieved by including the variable of total height. Considering the ease and accuracy in obtaining dbh data and the enormous time, errors and difficulty in obtaining height data, the equation form involving only dbh data as independent variable was recommended for use in estimating biomass for Gmelina in Oluwa forest reserve. [Copyright &y& Elsevier]

This paper presents a synthesis of assessment of sustainable biomass production potential in six Asian countries—China, India, Malaysia, Philippines, Sri Lanka and Thailand, and is based on the detailed studies carried out in these countries under the Asian Regional Research Programme in Energy, Environment and Climate (ARRPEEC). National level studies were undertaken to estimate land availability for biomass production, identify and evaluate the biomass production options in terms of yield per hectare and financial viability, estimate sustainable biomass production for energy, and estimate the energy potential of biomass production in the six Asian countries. Sustainable biomass production from plantation is estimated to be in the range of 182.5–210.5, 62–310, 0.4–1.7, 3.7–20.4, 2.0–9.9 and 11.6–106.6 Mt yr−1 for China, India, Malaysia, Philippines, Sri Lanka and Thailand, respectively. The maximum annual electricity generation potential, using advanced technologies, from the sustainable biomass production is estimated to be about 27, 114, 4.5, 79, 254 and 195 percentage of the total electricity generation in year 2000 in China, India, Malaysia, Philippines, Sri Lanka and Thailand, respectively. Investment cost for bioenergy production varies from US$381 to 1842 ha−1 in the countries considered in this study; investment cost for production of biomass varies from US$5.1 to 23 t−1. [Copyright &y& Elsevier]

Biomass for energetic use can be procured from various sources including willow short rotation crops (WSRC). The feasibility of willow crops, however, is dependent on the costs incurred by operations such as the plantation, maintenance, harvesting and transport. In small scale applications, cost balancing often results in the use of equipment designed for general agricultural purposes to carry on the operational management of WSRC. This study evaluated the productive performance in planting operations of WSRC for a planting equipment consisting of regular farming tractors used to propel machines designed to support planting on single twin rows. Planting equipment consisting of 4 different types of farming tractors fitted with willow planting equipment was tested in 14 filed plots to be able to compute the main performance indicators such as the net and gross productivity rates. An evident variability in terms of time consumption on categories was observed at plot-level, and the planting time was related to a great extent to the operated area. The size of areas subjected to planting operations was the most important factor that affected productive performance. Variation of net productivity rate was explained largely by the ratio of the length of headland returning maneuvers to total length covered in a given plot. The model developed for the total study time shows that, in the observed conditions, it may take more than 7 h to plant one hectare. The equipment taken into study stands for a flexible option for small-scale farmers which could increase the utilization rates of their farming tractors by using them in other agricultural operations when needed. In addition, the studied equipment fits well to very narrow and small-sized plots, as such situation is typical to Romania and other European countries. • Planting performance was strongly affected by the size of operated area. • Variability in size of operated area resulted in a variability of performance. • Operational speed has a low potential for improvement by its increment. • Re(engineering) the organization of work is more likely to improve the performance. • The analyzed system is flexible and can be adapted to small-size wide-spread plots. [ABSTRACT FROM AUTHOR]