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Charrey Sur, France

Bastien J.-C.,French National Institute for Agricultural Research | Marron N.,French National Institute for Agricultural Research | Berthelot A.,FCBA station nord est | Leplus A.,Association dInitiatives Locales pour lEnergie et lEnvironnement
Revue Forestiere Francaise | Year: 2011

Biomass enjoys special status amongst the sources of renewable energy because it is a source both of energy vectors and of carbonaceous molecules. According to European directives, the contribution of the biomass to the production of energy will triple in the next ten years. Faced with this challenge, it is commonly accepted that the main potential for growth comes from agriculture via dedicated production systems. Research in France on the use of perennial woody plants as crops dedicated to biomass production was conducted by INRA, FCBA and the AILE association several decades ago, in the wake of the first oil shocks. Trials were carried out in intensive forestry using stump sprouting trees: short and very short rotation coppices (SRC and VSRC, respectively). These trials showed that with productive varieties of species such as poplar, willow or eucalyptus grown by rotations of 2 to 7 years depending on the initial planting density, biomass output can reach between 8 and 15 metric tons of dry material per hectare per annum. Based on the results obtained by these three organisations on the basis of several dozen hectares of experimentally grown crops, the influence of a few cropping factors on the productivity of SRCs and VSCRs and the impact of the latter on site fertility were demonstrated. Some data concerning the energy and financial balances for these crops is also presented. Finally, some insight is provided about the role of SRCs and VSCRs in the area of environmental engineering (remediation, phytoextraction). By way of conclusion, a non-exhaustive list of ongoing research projects relating to dedicated systems for producing woody biomass is drawn up. Three main areas are currently apparent: improving the productivity and quality of the products derived from the biomass, acquiring better knowledge of the impact on the physical environment and biodiversity, and defining the criteria that determine their acceptability. Source

Berthelot A.,FCBA station nord est | Chevalier R.,IRSTEA | Archaux F.,IRSTEA | Gaudin S.,CRPF de Champagne Ardenne
Revue Forestiere Francaise | Year: 2011

This article essentially presents findings in the area of floristic biodiversity associated with poplar plantations in the large valleys of the Champagne area as compared to those in meadows and sub-natural forests. In addition to the current use of the soil, this study considers various factors of variation for poplar stands such as age, the presence of an understory and cropping history. The strongest effects relate to the age of the poplar stand and the presence or absence of an understory. The poplar stands of Champagne-Ardenne show significant floristic biodiversity due to their rapid dynamics ('nested' succession) and the divergences of plant communities depending on whether or not an understory is present. Poplar stands that have an understory are more favourable to forest communities, while poplars stands with no understory are more favourable to the flora typical of magnophorba. Source

Archaux F.,IRSTEA | Chevalier R.,IRSTEA | Berthelot A.,FCBA station nord est
Forest Ecology and Management | Year: 2010

Much research effort is being devoted to developing forest management practices with limited impacts on biodiversity. While the impact of poplar Populus sp. plantations on biodiversity is relatively well-known at the landscape scale, the impact of alternative management practices at the plantation scale has received much less attention. Yet biodiversity is likely to be impacted by the choice of the poplar clone, stem density at plantation, type and duration of the understory control, and age at which the poplars are harvested. In this study, we investigated the impact of these factors on herbaceous plant communities with data from plant surveys conducted in 85 young (2-5 years) and 96 mature (11-17 years) hybrid poplar high-forest plantations in northern France. On average, ruderal or generalist plants contributed to 40.5% of the plot species richness; tall herbs (60.2%), forest (26%) and meadow plants (13.8%) contributed to the remaining 59.5% more specialised species. Soil moisture and soil nitrogen were major determinants of plant communities: wet soils were favourable to tall herbs, while meadow and forest species preferred moist soils; a significantly lower diversity of the three species groups was reported in the nutrient richer soils (in mature plantations only for forest plants). Mean species richness decreased with plantation age except for forest species. Plant communities in young plantations showed little differences in composition according to the type of understory control (chemical, mechanical or both). The development of a shrubby layer in mature plantations was restricted to the drier soils and was detrimental to both meadow plants and tall herb species. Effects of previous land use on forest and tall herb species were found only in young plantations, suggesting a rapid reset of plant communities for these two groups. This may not be the case for meadow species as the influence of previous land use was significant in mature plantations only. Finally, clone type and stem density at plantation had no significant impact on plant communities. Adjusting age at which the poplars are harvested seems the only effective way to drive plant communities in high-forest poplar plantations: delaying poplar harvest (probably beyond 15-20 years) would benefit forest plants, while advancing poplar harvest (about 10 years) would benefit tall herbs, especially in wet soil conditions. © 2010 Elsevier B.V. All rights reserved. Source

Pinon J.,FCBA station nord est | Berthelot A.,FCBA station nord est | Fabre B.,French National Institute for Agricultural Research
Revue Forestiere Francaise | Year: 2011

Between 1987 and 2010, more than one hundred poplar cultivars were tested in order to assess their behaviour towards larch rust (Melampsora larici-populina). For most of them, we determined in the laboratory the virulences required to infect them. Then all clones were submitted to infection in three nurseries with a selected inoculum that reflected the diversity of the pathogen races. Susceptibility levels are provided for two periods and the virulences required for infection are given. Almost all the clones selected for complete resistance have lost this characteristic and the resulting infection level is often heavy, especially on inter-American clones. Source

De Morogues F.,Grenoble Institute of Technology | The N.N.,Grenoble Institute of Technology | Berthelot A.,FCBA station nord est | Melun F.,FCBA station sud ouest
Revue Forestiere Francaise | Year: 2011

Based on the experience of the FCBA institute of technology in the area of short rotation coppice (SRC) of poplar and eucalyptus and French and foreign technical reference material in the area of very short rotation coppice (VSRC), we were able to identify and estimate four standard scenarios for these two species ranging from the lowest densities (SRC 1,000 stems/ha) to the highest densities (VSRC for 10,000 stems/ha). Each planting density is associated with a given rotation time that varies from 2 to 10 years. The cost for these scenarios was reconstructed and compared to the cost of harvesting and the average sales price for the chips produced. With this data, a tentative assessment of the profitability of the SRC and VSRC scenarios was made. The results show that for these two species the profitability level for coppice increases the longer the harvesting cycles. The overall profitability for coppicing schemes appears to be moderate. Nonetheless, for players on the biomass market (industry, landowners and farmers) the return on investment in SRC/VSRC varies considerably. Profitability is achieved in practically every scenario depending on who implements it. Source

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