Short Rotation Coppice Plantations Research Articles

Floristic diversity in Short Rotation Coppice (SRC)plantations: Comparison between soil seed bank and recent vegetation

In the near future an increase in Short Rotation Coppice (SRC) plantations is to be expected. The objective was to compare the recent vegetation and the soil seed bank in SRC plantations to reveal the functioning of the soil seed bank for phytodiversity and vegetation structure after reconversion of SRC plantations into arable land. For the analyses, above-ground vegetation surveys and soil seed bank samples of six German and four Swedish SRC plantations were used. Similarity in composition of soil seed banks and recent vegetation was low in terms of species, plant strategy types, species habitat preferences and seed longevity. On average, the proportion of common species of recent vegetation and soil seed bank was 8.4 % (± 6.7 % SD). The recent vegetation was dominated by competitive (c) plant species while in the soil seed banks highest proportions were detected for ruderals (r) and competitors (c). Species with long-term persistent seeds had the highest contribution to both the recent vegetation and the soil seed banks. Grassland species had highest species habitat preference proportion in the recent vegetation. The soil seed banks contained predominantly ruderal species and woodland species were almost absent. Due to the poor coherence of seed bank vs. recent vegetation, we conclude that the site history has only a minor influence on phytodiversity in SRC plantations, suggesting that recent vegetation composition is mainly due to the species pool of the adjacent vegetation and site conditions like below-canopy irradiance and site nutrition.

Assessment of variability in biomass yield and quality: what is an adequate size of sampling area for miscanthus?

To diversify energy crop production and improve its biodiversity and sustainability, there is currently a search for alternative energy crops. Many of the newly arising alternatives are perennial species such as the C4 grass miscanthus. The assessment of reliable data is a prerequisite for understanding the performance of these crops and developing corresponding management systems. However there is great uncertainty concerning research methodology for these crops. When data are collected from small plots of perennial crops, such as miscanthus or short rotation coppice plantations, a larger variability is expected than for cereals. A square meter cut, corresponding to harvest practice in cereals, is not sufficient for perennial C4 grasses and is not recommended for these species. The aim of this research was to identify an adequate size of sampling area for miscanthus to estimate the true biomass yield or quality. For this purpose, whole plots of 10- and 14-year old miscanthus stands were divided into smaller subplots. These were used to calculate variances for various sizes of simulated plots. The variances for all traits in the experiments were rather high when the sampling area was smaller than 2 m². A cutting regime of more than 5.6 m² would be advisable, but an area of 3 m² is sufficient to eliminate approximately 90% of the variances and is therefore an adequate size of sampling area.

Stand age characteristics and soil properties affect species composition of vascular plants in short rotation coppice plantations

Woody biomass plantations on agricultural sites are an attractive source of biomass for bioenergy, but their effects on local biodiversity are unclear. This study’s objective was to evaluate the influences of light availability, plantation age, and soil properties on phytodiversity in short rotation coppice (SRC) plantations. Ground vegetation mapping, irradiance measurement (PAR), and surface soil analyses were conducted in 15 willow and poplar SRC plantations in Central Sweden and Northern Germany. We performed different multivariate statistical methods like cluster analysis (CA), principal component analysis (PCA), and canonical correspondence analysis (CCA) in order to analyze species composition and the influence of irradiance, age, and soil properties on phytodiversity. CA revealed highest species composition similarities in SRC plantations in close proximity. PCA identified humus quality/essential plant nutrients, plantation age/irradiance effects, soil acidity and shoot age as the four principal components of the recorded parameters. The ground vegetation cover was negatively correlated with the plantation age component and positively with the nutrient component. With an increase in the plantation age component, a shift in species composition was proven towards more forest habitat species, more nutrient-demanding species, and increasing occurrence of indicator species for basic soils. Applying Ellenberg indicator values, basic soil indicator species corresponded in occurrence to increasing nutrient availability. However, species richness was not related to any of our studied site variables. Judged from CCA, species composition in SRC plantations was influenced by plantation age/irradiance, and nutrient availability; soil acidity and shoot age had no significant influence. Young poplar and willow SRC plantations showed greatest variation in photosynthetically active radiation (PAR). Our findings suggest that phytodiversity in SRC plantations depends mainly on plantation age and thus shifts over time.

Life cycle assessment: an application to poplar for energy cultivated in Italy

The development of the bioenergy sector has led to an increasing interest in energy crops. Short rotation coppices (SRC) are forestry management systems in which fast-growing tree species are produced under intensive cultivation practices to obtain high wood chips yields. In Italy, most SRC plantations consist of poplar biomass-clones. SRC plantations can be carried out with different management systems with diverse cutting times; consequently, the cultivation system can be crucial for attaining high yields depending on: i) short and ii) medium cutting frequency. Nowadays, the larger part of Italian SRC is based on 2-year cutting short rotation forestry (SRF) but the best quality of wood chips is linked to 5-year plantation medium rotation forestry (MRF). This work compares an SRF and an MRF poplar plantation located in the Po Valley in northern Italy. In particular, a life cycle assessment (LCA) was carried out to evaluate their energy demand and greenhouse gas emissions. The LCA software SimaPro 7.10 was used to create the LCA model and to assure an accurate impact assessment calculation. The analysis shows several differences between MRF and SRF in terms of fertiliser requirements and intensive agricultural activities. Results highlight that MRF produces a more sustainable wood chip production than SRF according to energy and environmental concerns. Furthermore, hot spots were identified in both SRF and MRF due to the high energy consumption and the related emissions. These hot spots were: i) mineral fertilisation; ii) mechanical weed-control; iii) harvesting and biomass transport.

Life cycle assessment: an application to poplar for energy cultivated in Italy

The development of the bioenergy sector has led to an increasing interest in energy crops. Short rotation coppices (SRC) are forestry management systems in which fast-growing tree species are produced under intensive cultivation practices to obtain high wood chips yields. In Italy, most SRC plantations consist of poplar biomass-clones. SRC plantations can be carried out with different management systems with diverse cutting times; consequently, the cultivation system can be crucial for attaining high yields depending on: i) short and ii) medium cutting frequency. Nowadays, the larger part of Italian SRC is based on 2-year cutting short rotation forestry (SRF) but the best quality of wood chips is linked to 5-year plantation medium rotation forestry (MRF). This work compares an SRF and an MRF poplar plantation located in the Po Valley in northern Italy. In particular, a life cycle assessment (LCA) was carried out to evaluate their energy demand and greenhouse gas emissions. The LCA software SimaPro 7.10 was used to create the LCA model and to assure an accurate impact assessment calculation. The analysis shows several differences between MRF and SRF in terms of fertiliser requirements and intensive agricultural activities. Results highlight that MRF produces a more sustainable wood chip production than SRF according to energy and environmental concerns. Furthermore, <em>hot spots</em> were identified in both SRF and MRF due to the high energy consumption and the related emissions. These <em>hot spots </em>were: i) mineral fertilisation; ii) mechanical weed-control; iii) harvesting and biomass transport.

Biomass Production with Willow and Poplar Short Rotation Coppices on Sensitive Areas—the Impact on Nitrate Leaching and Groundwater Recharge in a Drinking Water Catchment near Hanover, Germany

In a lowland drinking water catchment area, nitrate leaching as well as groundwater recharge (GWR) was investigated in willow and poplar short rotation coppice (SRC) plantations of different ages, soil preparation measures prior to planting and harvesting intervals. Significantly increased nitrate concentrations of 16.6 ± 1.6 mg NO3-N L−1 were measured in winter/spring 2010 on a poplar site, established in 2009 after deep plowing (90 cm) but then, subsequently decreased strongly to below 2 mg NO3-N L−1 in spring 2011. The fallow ground reference plot showed nitrate concentrations consistently below 1 mg L−1 and estimated annual seepage output loss was only 1.36 ± 1.1 kg ha−1 a−1. Leaching loss from a neighboring willow plot from 2005 was 14.3 ± 6.6 kg NO3-N ha−1 during spring 2010 but decreased to 2.0 ± 1.5 kg NO3-N ha−1 during the subsequent drainage period. A second willow plot, not harvested since its establishment in 1994, showed continuously higher nitrate concentrations (10.2 ± 1.7 NO3-N L−1), while a neighboring poplar plot, twice harvested since 1994 showed significantly reduced nitrate concentrations. Water balance simulations, referenced by soil water tension and throughfall measurements, showed that at 655 mm annual rainfall, GWR from the reference plot (300 mm a−1) was reduced by 40 % (to 180 mm a−1) on the 2005 willow stand, mainly due to doubled rainfall interception losses. However, transpiration was limited by low soil water storage capacities, which in turn led to a moderate impact on GWR. We conclude that well-managed SRC on sensitive areas can prevent nitrate leaching, while impacts on GWR may be mitigated by management options.

The economics of short rotation coppice in Germany

Abstract Short Rotation Coppice (SRC), which entails managing wood plantations as perennial energy crops on agricultural land, has the potential to contribute significant amounts of wooden biomass to Europe's energy mix. Yet, uncertainty prevails about the future of key economic variables determining the viability of SRC cultivations. Consequently, agriculturists face challenges when conducting ex-ante economic analyses of SRC projects and measuring performance against the alternative, agricultural crops. This paper scrutinises five key determinants of SRC economic viability: yield level, woodchip market price, subsidies, cost level and opportunity costs for conventional agricultural crops. By utilising site-specific conditions and different future scenarios we provide a comprehensive economic appraisal of SRC plantations for agriculturists. We focus our analysis on Germany. Our results show that SRC plantations are less profitable under the medium scenario when compared with agricultural crops. Notwithstanding, favourable political and economic conditions such as subsidies, lower costs and higher woodchip prices can lead to SRC's superior profitability. If the German government is serious about improving investments conditions for commercial SRC plantations, we recommend introducing sufficient, efficient and consistent subsidies.

Environmental Impacts of Short Rotation Coppice (SRC) Grown for Biomass on Agricultural Land

This issue of BioEnergy Research highlights the activitieswithin a European Union research project funded by ERA-NET Bioenergy, “Reducing environmental impact of SRCthrough evidence-based integrated decision support tools”(RATING-SRC). The project goal was to provide scientificevidence for evaluatingthe impacts —positiveandnegative—of short rotation coppice (SRC) plantations on soil, water,biodiversity, and landscape issues and also to propose waysto mitigate the negative and increase the positive impacts.Commercial SRC plantations are currently grown at limit-edscaleinsomecountries(e.g.,Sweden),buttheareaofSRCplantationshastoincreasedramaticallyinthefutureiftheyareto contribute significantly to the replacement of fossil energysources. Thus, a rapid increase of agricultural land dedicatedto SRC with willow (Salix spp.) or poplar (Populus spp.) forproduction of biomass for heat and/or electricity is projectedin the short-term in many regions of the world. A large-scaleshift from “conventional” arable crops to SRC will haveimplications on a range of environmental issues, and large-scale implementation of those crops for bio-energy purposemakes sense only if they prove to reduce negative effects onthe environment, especially when compared with other alter-natives for reduction of fossil energy sources. As a perennialcrop,SRCdiffersfrommostarablecropsinphysicaltraitsandmanagement practices. Results so far imply many positiveenvironmental benefits due to SRC implementation, but theeffects that SRC will have on the environment depend on theexisting or previous land use, the scale of planting and themanagement practices applied. In addition, SRC is a newproduction system for most regions in which it might begrown in future, and many uncertainties exist with respect tothe environmental impacts of those plantations on soil, water,biodiversity, and landscape issues.This special issue contains sevenpaperscoveringthetopicareasofSRCeffectsonissuesofwaterandsoil(twopapersbyDimitriou et al., Schmidt-Walter and Lamersdorf), biodiver-sity (Baum et al.), and the overall impact that these planta-tions may have on the environment and sustainability(Busch, Englund et al., Langeveld et al.). The paper on soilissues by Dimitriou et al. highlights the results for pH,organic carbon (C), and trace element concentrations in thesoil of 14 long-term (10–20 years) commercial willow SRCfields in Sweden when compared with those in adjacent,conventionally managed arable soils. The paper on waterissues by Dimitriou et al. reports the effects of SRC on waterquality by determining differences in leaching of nitrogenand phosphorus to groundwater of 16 commercial SRCstands in Sweden compared to adjacent arable fields grownwith “ordinary” crops. Schmidt-Walter and Lamersdorfdescribe effects on groundwater quality, specifically the po-tential effects of SRC grown under different managementregimes on groundwater recharge. Based on flora inventoriesin eight landscapes located in two European regions(Germany and Sweden), the paper by Baum et al. focus-es on the diversity of higher plants as an indicator ofbiodiversity in willow and poplar SRC, including variousscales ranging from habitat to landscape level diversity.The contribution by Busch is an attempt to assess theimpact of SRC on various landscape functions with thehelp of GIS-based tools. Englund et al. focus on thepotential effects of sustainability requirements within theEU Renewable Energy Directive (RED) on different stake-holders along SRC bioenergy supply chains, assessing theirusefulness in ensuring that SRC bioenergy is produced with

Changes in Organic Carbon and Trace Elements in the Soil of Willow Short-Rotation Coppice Plantations

Short rotation coppice (SRC) is a biomass production system for energy usually grown on former agricultural land with fast-growing tree species. In Sweden, willow SRC has been grown since the late 1980s. SRC on arable soils may induce changes in some soil quality parameters due to differences in crop characteristics and management practices. In this study, pH, organic carbon (C), and trace element concentrations in the soil of 14 long-term (10–20 years) commercial willow SRC fields in Sweden were compared with those in adjacent, conventionally managed arable soils. The results showed that organic C concentrations in the topsoil and subsoil of SRC fields were, on average, significantly higher (9 % in topsoil, 27 % in subsoil) than in the reference fields. When comparisons were made only for the ten sites where the reference field had a crop rotation dominated by cereal crops, the corresponding figures were 10 % and 22 %. The average concentration of cadmium (Cd), which is considered the most hazardous trace element for human health in the food chain, was 12 % lower in the topsoil of SRC fields than in the reference fields. In the corresponding comparison of subsoils, no such difference was found. For chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn), there were no significant differences in concentrations between SRC fields and the reference fields in either topsoil or subsoil. Negligible differences in pH in the same comparisons were found.

Short Rotation Coppice (SRC) Plantations Provide Additional Habitats for Vascular Plant Species in Agricultural Mosaic Landscapes

Increasing loss of biodiversity in agricultural landscapes is often debated in the bioenergy context, especially with respect to non-traditional crops that can be grown for energy production in the future. As promising renewable energy source and additional landscape element, the potential role of short rotation coppice (SRC) plantations to biodiversity is of great interest. We studied plant species richness in eight landscapes (225 km2) containing willow and poplar SRC plantations (1,600 m2) in Sweden and Germany, and the related SRC α-diversity to species richness in the landscapes (γ-diversity). Using matrix variables, spatial analyses of SRC plantations and landscapes were performed to explain the contribution of SRC α-diversity to γ-diversity. In accordance with the mosaic concept, multiple regression analyses revealed number of habitat types as a significant predictor for species richness: the higher the habitat type number, the higher the γ-diversity and the lower the proportion of SRC plantation α-diversity to γ-diversity. SRC plantation α-diversity was 6.9 % (±1.7 % SD) of species richness on the landscape scale. The contribution of SRC plantations increased with decreasing γ-diversity. SRC plantations were dominated more by species adapted to frequent disturbances and anthropo-zoogenic impacts than surrounding landscapes. We conclude that by providing habitats for plants with different requirements, SRC α-diversity has a significant share on γ-diversity in rural areas and can promote diversity in landscapes with low habitat heterogeneity and low species pools. However, plant diversity enrichment is mainly due to additional species typically present in disturbed and anthropogenic environments.

Establishment and two-year growth of a bio-energy plantation with fast-growing Populus trees in Flanders (Belgium): Effects of genotype and former land use

Abstract In April 2010, a large-scale Short Rotation Coppice (SRC) plantation was established with mainly poplar ( Populus spp.) on a former agricultural site (cropland and pasture) in Flanders. The 12 selected genotypes planted were assessed on establishment and production characteristics during the first two years of growth and were found highly productive, with a volume index ranging between 1.00 (±0.68) and 1.93 (±0.97) dm³ in growing season 1 (GS1) and between 2.75 (±1.70) and 11.91 (±6.33) dm³ in growing season 2 (GS2). Despite high survival rates of the cuttings after planting, competitive weeds and management operations increased tree mortality during the growing season from 3.4 % up to 18.2 % averaged over the entire plantation. Weed control therefore turned out to be the key factor in the establishment success. Only a minor influence of former land use was observed during GS1, which is explained by the non-limiting nutrient conditions on both former cropland and pasture, and which disappeared during GS2. These productive soils also explained the high growth rates, with an average tree height of 247 cm and 445 cm and stem diameter (at 22 cm height) of 25.21 mm and 40.73 mm after GS1 and GS2, respectively. Genotypic and parentage variations were found to be less pronounced during GS1, and increased during GS2 as expected. The maximum leaf area index and total leaf area duration were shown to be good indicators of production and growth performance. The results of this paper confirm the high potential of SRC with poplar on agricultural land for bio-energy purposes.

High value of short rotation coppice plantations for phytodiversity in rural landscapes

AbstractThe demand for wood from short rotation coppice (SRC) plantations as a renewable energy source is currently increasing and could affect biodiversity in agricultural areas. The objective was to evaluate the contribution of SRC plantations to phytodiversity in agricultural landscapes assessed as species richness, species–area relationships, Shannon indices, detrended correspondence analysis on species composition, Sørensen similarities, habitat preference proportions, and species proportions found in only one land use. Vegetation surveys were conducted on 12 willow (Salix spp.) and three poplar (Populus spp.) coppice sites as well as on surrounding arable lands, grasslands and forests in central Sweden and northern Germany. SRC plantations were richer in plant species (mean: 30 species per 100 m²) than arable land (10), coniferous forests (13) and mixed forests in Germany (12). Comparing SRC plantations with other land uses, we found lowest similarities in species composition with arable lands, coniferous forests and German mixed forests and highest similarities with marginal grassland strips, grasslands and Swedish mixed forests. Similarity depended on the SRC tree cover: at increased tree cover, SRC plantations became less similar to grasslands but more similar to forests. The SRC plantations were composed of a mixture of grassland (33%), ruderal (24%) and woodland (15%) species. Species abundance in SRC plantations was more heterogeneous than in arable lands. We conclude that SRC plantations form novel habitats leading to different plant species composition compared to conventional land uses. Their landscape‐scale value for phytodiversity changes depending on harvest cycles and over time. As a structural landscape element, SRC plantations contribute positively to phytodiversity in rural areas, especially in land use mosaics where these plantations are admixed to other land uses with dissimilar plant species composition such as arable land, coniferous forest and, at the German sites, also mixed forest.

Slow expansion and low yields of willow short rotation coppice in Sweden; implications for future strategies

About 16 000 ha of commercial willow Short Rotation Coppice (SRC) fields for production of biomass for energy were planted in the early 1990s in Sweden. The cultivated with SRC area has remained almost stable and was slightly decreased during the last years despite the incentives and predictions for drastic increases. Similar incentives and predictions in other countries have been lately launched. The bioenergy produced in the planted SRC areas in Sweden has been lower than anticipated, partly due to the lower than expected biomass yields and the termination of some willow SRC plantations. Explanations for the low yields are depicted based on analyzing the results of a survey where 175 willow SRC growers participated. Lower biomass yields are attributed to: (i) the low input in management activities; (ii) the choice of land for the willow SRC plantation; (iii) and the level of personal involvement of the farmer. Understanding the reasons to earlier years' performance of willow SRC is important for development of better performing systems in the future, in Sweden as well as in other countries. © 2011 Elsevier Ltd.

The carbon implications of large‐scale afforestation of agriculturally marginal land with short‐rotation willow in Saskatchewan

AbstractAfforestation with short‐rotation coppice (SRC) willow plantations for the purpose of producing bioenergy feedstock was contemplated as one potential climate change mitigation option. The objectives of this study were to assess the magnitude of this mitigation potential by addressing: (i) the land area potentially available for SRC systems in the province of Saskatchewan, Canada; (ii) the potential biomass yields of SRC plantations; and (iii) the carbon implications from such a large‐scale afforestation program. Digital soils and land‐use data were used to identify, map, and group into clusters of similar polygons 2.12 million hectares (Mha) of agriculturally marginal land that was potentially suitable for willow in the Boreal Plains and Prairies ecozones in Saskatchewan. The Physiological Principles in Predicting Growth (3PG) model was calibrated with data from SRC experiments in Saskatchewan, to quantify potential willow biomass yields, and the Carbon Budget Model of the Canadian Forest Sector (CBM‐CFS3), was used to simulate stand and landscape‐level C fluxes and stocks. Short‐rotation willow plantations managed in 3 year rotations for seven consecutive harvests (21 years) after coppicing at Year 1 produced about 12 Mg ha−1 yr−1 biomass. The more significant contribution to the C cycle was the cumulative harvest. After 44 years, the potential average cumulative harvested biomass C in the Prairies was 244 Mg C ha−1 (5.5 Mg C ha−1 yr−1) about 20% higher than the average for the Boreal Plains, 203 Mg C ha−1 (4.6 Mg C ha−1 yr−1). This analysis did not consider afforestation costs, rate of establishment of willow plantations, and other constraints, such as drought and disease effects on biomass yield. The results must therefore be interpreted as a biophysical mitigation potential with the technical and economic potential being both lower than our estimates. Nevertheless, short‐rotation bioenergy plantations offer one potential mitigation option to reduce the rate of CO2 accumulation in the earth's atmosphere and further research is needed to operationalise such a mitigation effort.

Genetic mapping of rust resistance loci in biomass willow

Rust diseases caused by Melampsora spp. represent a major threat to the productivity of short rotation coppice (SRC) willows grown for biomass, causing yield losses of up to 40%. The routine use of fungicide in SRC plantations is not a viable option because of economic and environmental considerations; thus, breeding for rust resistance is a major target for willow breeding programmes. To characterise the genetic basis of rust resistance in willow and provide targets for use in future marker-assisted selections, quantitative trait analyses were performed using a large full-sib mapping population (K8) which segregates for rust resistance and several other important agronomic traits. Rust resistance in field conditions was assessed in three consecutive years. For a more detailed genetic dissection, laboratory inoculation tests using isolates of two distinct and prevalent pathotypes (LET1 and LET5) were also performed. For field-based resistance, a major quantitative resistance locus, designated SRR1 (Salix Rust Resistance 1), was detected in addition to several quantitative trait loci (QTL) of more modest effect. Inoculation test data also supported an important role for SRR1. Specific interactions between particular rust isolates and different QTL were detected, and QTL that only influenced resistance in field conditions were identified. The QTL reported here represent an important basis for the future development of markers for use in willow breeding programmes. As the linkage map for the K8 population is anchored to the Populus trichocarpa genome sequence, a more efficient marker development for future fine-scale mapping and candidate gene identification is possible.

Sewage sludge and wastewater fertilisation of Short Rotation Coppice (SRC) for increased bioenergy production—Biological and economic potential

Application of municipal residues, e.g. wastewater or sewage sludge, to Short Rotation Coppice (SRC) is among the most attractive methods for attaining environmental and energy goals set for Europe. At current woodchip prices in Sweden, the gross margin for SRC cultivation is positive only if biomass production is >9 t DM/ha yr. The gross profit margin increases (by 39 and 199 €/GJ, respectively) if sewage sludge and wastewater are applied to SRC. Application of residues to SRC has proved to be an acceptable alternative treatment method, and the farmer’s profit can be markedly increased if compensation is paid for waste treatment. If all available sludge and wastewater were applied to SRC plantations, they could be grown on large agricultural areas in Europe, and c. 6000 PJ of renewable energy could be produced annually. However, a more economical landuse strategy, e.g. the use of more P-rich residues, appears more rational, and is biologically justifiable.

Relation between leaf rust (Melampsora epitea) severity and the specific leaf area in short rotation coppice willows

Willow leaf rust (Melampsora epitea) is an important leaf pathogen in short rotation coppice plantations. Although ecological factors influencing rust severity are rather well known, to date, the connections between leaf morphological traits and rust infections are poorly studied. The aim of this study was to examine the relation between rust severity and specific leaf area (SLA). Willow leaves of three different clones from waste-water-irrigated and non-irrigated plantation areas were used. The results revealed a significant positive correlation between SLA and rust severity. There were clone specific differences whereas more rust pustules were always accompanied with higher SLA. Waste-water-irrigated plants had higher SLA and always more rust damages. These results suggest that leaves with low SLA are less susceptible to leaf rust in various conditions.

Potentials and impacts of short-rotation coppice plantation with aspen in Eastern Germany under conditions of climate change

Woody biomass generated in short-rotation coppice (SRC) plantations with aspen (Populus tremula L.) has good properties for bioenergy crop production: annual yields are high, labour input per year is low, and it is ecologically valuable because of the multi-year rotation periods. Eastern Germany has a special advantage in producing bioenergy crops: the former “agricultural cooperatives” built up quite large farms with, compared to Western Germany, comparatively large fields. Therefore, a modelling study of the potential and the impacts of aspen SRC plantations in the five eastern federal states of Germany under the recent climate and future climate projections was conducted. The ecophysiological forest growth model 4C was used to simulate the growth of aspen SRC plantations and their impacts on carbon in soils, and groundwater recharge, on selected suitable areas currently under crops but with marginal site conditions for cropping. A clear signal to enhanced growth condition over the whole area can be seen in the simulation of the mean annual woody biomass yield under conditions of climate change, which increased from 7.47 t DW ha−1 a−1 under the recent climate to 9.26 t DW ha−1 a−1 at the end of the considered future period 2034–2055 under climate change. The mean soil carbon sequestration rate was 0.81 t C ha−1 a−1 under the recent climate and could rise up to 0.93 t C ha−1 a−1 under the assumption of climate change. On the other hand, the mean annual percolation rate, used as an indicator of impacts on the regional water budget, will diminish under future climatic conditions. The results suggest that aspen SRC plantations are a suitable contribution to regional CO2 mitigation and carbon sequestration under possible change of climate, but that negative impacts on the regional water budget are possible.

First Report of Phoma exigua var. populi Causing Canker of Twigs and Shoots of Poplar in the Czech Republic.

During 2007 and the spring of 2008, a disease of poplars (Populus spp.) resembling the Dothichiza canker was found in plantations of fast-growing trees in central Bohemia and in southern Moravia where it was more abundant. The yellowish brown-to-brown, round or elongated cankers occurred on damaged shoots and twigs. Tissues directly under the bark were discolored and turned black. As the cankers enlarged, infected shoots and twigs died after several months. Small, black, gregarious pycnidia were observed under the bark or in lenticels after several weeks. The disease occurred on Populus nigra, P. × euroamericana cvs. Regenerata, Robusta, Brabantica, Spreewald, CZ-425/58, Blanc du Poitou, and Flaschlanden, and other Populus spp. Isolates of a species of Phoma were acquired by culturing damaged tissues on agar plates containing 3% oatmeal agar (OA) and 2% malt agar. Initial identification of the isolates was done by cultural and morphological characteristics (1). Colonies were floccose, aerial mycelium was olivaceous gray to gray, reverse olivaceous gray sometimes with darker tones at the margins or in the colony center, and NaOH reaction was negative. The growth rate was 42 to 56 in diameter after 7 days at 20°C on OA (optimum temperature for growth was 22°C with a minimum of 1°C and a maximum of 28 to 29°C). Pycnidia in culture scattered, were globose or subglobose, obviously with one nonpapillate ostiolum, olivaceous black or black, 120 to 370 μm in diameter, and conidial exudate was whitish. Phialides were globose to ampulliform and 3 to 7 × 3 to 6 μm. Conidia were hyaline, ellipsoidal, often guttulate, 3.1 to 7.8 × 1.9 to 3.1 μm, and L/B ratio 1.4:3.1. Septate conidia occurred only on natural substrate up to 10.6 × 3.9 μm. Morphological and cultural characteristics resembled those of P. exiqua var. populi Gruyter & P. Scheer (1). The internal transcribed spacer (ITS) sequence (GenBank Accession No EU562206) for the representative isolate (CCF No 3759) confirmed 100% identity to P. exigua. Pathogenicity was confirmed with 1-year-old P. nigra plants during a 2-month greenhouse experiment at 15 to 20°C. Fifteen replicate plants were wounded (5-mm diameter), inoculated with 5-mm OA plugs from actively growing colonies (isolate CCF No 3759), and sealed by Parafilming. An additional 15 control plants following wounding were inoculated with a sterile agar plug. After 3 to 4 weeks, yellowish or brownish necrotic lesions ranging from 1 to 1.5 cm long developed on all inoculated plants. The pathogen was successfully reisolated from lesions and the control plants were asymptomatic. P. exigua var. populi is considered an opportunistic poplar and willow pathogen (2) that becomes more important in winter (1). The pathogen potentially invades host tissues damaged by frost, sun scald, or weakened by excessive transpiration during sunny winter days. To our knowledge, this is the first record of the pathogen on poplars in the Czech Republic, which may have an economic impact on short-rotation coppice plantations.

Supporting programmes of the growing of short rotation coppices in the Czech Republic

This article presents some partial conclusions from the solution to the Research Project QF 4142 Higher exploitation of non-food production in the industry. The funding and supporting programmes of the growing of short rotation coppices (SRC) are described. The establishment of short rotation coppices and the subsequent exploitation of wood mass are promising trends of diversification of farmers’ activities in the rural space. Plot sizes in ha and financial support to the establishment of the SRC plantations are given for 2001–2004, when a total of 166 ha of supported short rotation coppices was established. The establishment support is paid at a single installment while the amount paid for the establishment of the SRC production plantation is 60 000 CZK/ha and the amount paid for the establishment of mother plantation (reproduction plantation) is 75 000 CZK/ha.