Short rotation coppice trees in contaminated sites: A study of wood characteristics for bio-concrete applications

Digging deeper - soil water availability reshapes fine root distribution in hybrid Poplar (Populus Nigra × P. maximowiczii) short-rotation coppice plantation

Effective water resource management in agriculture is a pivotal challenge for environmental sustainability and the economic viability of crop production. The present study, conducted at the CREA research station (Monterotondo, Italy), analyzed a precision irrigation strategy based on an automated drip irrigation system with soil moisture sensors, applied to a 15-year-old high-density poplar plantation for energy production. Five treatments were compared: a non-irrigated control (T0) and four irrigation levels based on soil moisture thresholds (T1 ≤ 20%, T2 ≤ 30%, T3 ≤ 40%, T4 ≤ 50%). The aim of this study was to assess the economic feasibility of irrigated poplar plantations, considering expected increases in biomass production and related environmental impacts. The economic evaluation used the Life Cycle Costing (LCC) method, while the environmental assessment applied Life Cycle Assessment (LCA) with the AWARE indicator to quantify the water scarcity footprint. Finally, an integrated assessment using the TOPSIS multi-criteria method was performed to identify the most sustainable treatment. Over the 15-year period, T0 (no irrigation) was the preferred option (Preferred Index Pi = 1.000), followed by T3 (Pi = 0.637) and T4 (Pi = 0.586), considering equal weighting of economic and environmental impacts. Conversely, the low irrigation treatment (T1) was the least sustainable (Pi = 0.379), followed by T2 (Pi = 0.486). While irrigation appears unviable if environmental impacts are prioritized, higher biomass value can improve the economic sustainability of treatments with greater water use (T3 and T4) when economic factors dominate.

Importance of short rotation coppice strips within a modern alley cropping agroforestry system as habitat and potential biotope network element for forest carabids (Coleoptera: Carabidae) – Alley cropping agroforestry systems with short-rotation coppice strips (CS) are novel land use systems in which rows of fast-growing trees are integrated between arable fields to simultaneously produce woody bio- mass and crops. CS introduce new structures and habitats into intensively used agricultural landscapes. We investigated the habitat function of two CS-variants for carabid beetles on an experimental site in Lower Sa- xony (Northern Germany) with a particular focus on their potential as habitat and biotope network element for forest species. The CS-variants included (1) CS-K: conventional variant with poplar clones harvested in short intervals, and (2) CS-A: incorporating aspen trees with longer rotation periods in addition to poplar clones. In addition, we surveyed various woody habitats in the surrounding landscape (woodland, tree row, hedgerow, short-rotation coppice (SRC) plantation) to determine the forest species inventory and potential source habitats/populations of forest carabids, and to compare their habitat function with the CS-variants. Carabid beetles were sampled with pitfall traps from late March to early October 2024. Both CS variants, like the hedgerow and the SRC, were dominated by eurytopic species. Among the total of 11 forest species detected in the reference habitats forest and tree row (including Carabus glabratus and Abax parallelus, two relict species of ancient woodland), only two species associated with light and open forests (Carabus coria- ceus and Limodromus assimilis) were recorded in low numbers within the CS, the hedgerow, and the SRC. The carabid beetle assemblages of the two CS-variants were similar in terms of species richness and com-po- sition. We conclude that the studied CS currently hold no significant value as habitat and potential biotope network element for forest carabids in the considered landscape. We consider their potential to develop into suitable habitat or ecological corridors for forest species to be low, as their already limited habitat potential is regularly reduced by harvesting at short intervals, and the CS will be removed as planned in 10–15 years due to the declining resprouting capacity of the trees. However, we assume that CS can enhance carabid beetle diversity compared to arable fields lacking woody structures and may enhance landscape permeability for species that tend to avoid intensively used, structurally simplified agricultural landscapes.

The incorporation of cattle slurry in soil in short-rotation-cycle poplar cultivations can be a win–win strategy, insofar as a main feedstock derived from local intensive dairy cattle breeding can be used as a natural fertilizer and in bioenergy produced in the same region. The circularity of this process can contribute to boosting local socio-economic value. In this context, this work involved the installation of a poplar SRC plantation with a density of 5330 trees ha−1 in a 4000 m2 moderately fertile flat site, which was formerly used as a vineyard. Mechanical dosages of slurry of 0, 26.6, 53.2, and 106.5 Mg ha−1, designated as treatments T0, T1, T2, and T3, were applied three times per year during 2019, 2020, and 2021. The variables quantified were related to plant growth, biomass productivity and mass balances of K, P, Cu, Zn, Mg, and N, and organic matter in the whole soil, plant, and slurry system during the first rotation cycle. For treatments T0 and T1, all these seven chemical components showed positive balances in the system, with cumulative demand by soil and biomass being higher than cumulative supply by slurry. Negative balances occurred for P with T2 and T3 and for Zn with T3, so that an overall condition of nutrient saturation of the whole system was not achieved. A no-slurry application, or at most a moderate application equivalent to T1, in the second rotation cycle should therefore be prescribed to allow a nutrient equilibrium status to be achieved through internal seasonal recycling mechanisms. The biomass average productivities ranged from 6.1 to 11.8 Mg ha−1 y−1, peaking under treatment T2, and are within the typical values for a first rotation cycle for poplar SRCs. The biomass fuel quality was not affected by the slurry treatments. A good performance of plant total height and growth in diameter at breast height suggested that poplar trees were not stressed by the applied slurry. Only treatment T1 could assure that cattle CO2-eq methane emissions were overall equilibrated by the carbon sequestration from poplar cultivation, with an absence of climatic-warming impacts. Treatments T2 and T3 could only partially minimize that impact, which would always exist. Globally, this site-specific analysis showed that, under moderately fertile conditions, controlled cattle slurry fertilization of poplar SRC cultivations, which would assure a long-term steady-state equilibrium, can be a viable option to contribute to decentralized production of bioenergy in rural communities.

Background and AimsThe establishment of bioenergy plantations as short-rotation coppice poplar systems has been proposed as a sustainable strategy to mitigate climate change through carbon capture. This study evaluates changes in soil organic carbon (SOC) after 12 years of poplar cultivation on former cropland and grassland in Belgium using repeated soil sampling to assess SOC stock changes and in-growth cores to identify carbon input pathways.MethodsUsing isotope tracing and in-growth cores with treatments excluding roots, mycorrhizae and above-ground inputs, we quantified the contributions of roots, mycorrhizae, and dissolved organic matter to new SOC formation and their interaction with the mineralization of native SOC.ResultsResults showed a significant increase in SOC in former croplands while grasslands experienced a slight SOC reduction, highlighting the influence of previous land use on SOC accrual potential. Root-derived inputs surpassed mycorrhizal contributions to SOC formation although both played a role in achieving a positive SOC balance.ConclusionThis study underscores the critical role of roots in SOC accumulation and the importance of initial soil conditions when designing SOC accrual strategies through bioenergy plantations.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11104-025-07995-2.

Coarser root residues are a major subsoil carbon sink after re-conversion of poplar short rotation coppice plantation to cropland

Willow stands (Salix spp.) are an essential part of riparian ecosystems, as they sustain biodiversity and provide bioenergy solutions. The present review synthesizes the global scientific literature about the management of willow stands. In order to achieve this goal, we used a dual approach combining bibliometric analysis with traditional literature review. As such, we consulted 416 publications published between 1978 and 2024. This allowed us to identify key species, ecosystem services, conservation strategies, and management issues. The results we have obtained show a diversity of approaches, with an increase in short-rotation coppice (SRC) systems and the multiple roles covered by willow stands (carbon sequestration, biomass production, riparian restoration, and habitat provision). The key trends we have identified show a shift toward topics such as climate resilience, ecological restoration, and precision forestry. This trend has become especially pronounced over the past decade (2014–2024), as reflected in the increasing use of these keywords in the literature. However, as willow systems expand in scale and function—from biomass production to ecological restoration—they also raise complex challenges, including invasive tendencies in non-native regions and uncertainties surrounding biodiversity impacts and soil carbon dynamics over the long term. The present review is a guide for forest policies and, more specifically, for future research, linking the need to integrate and use adaptive strategies in order to maintain the willow stands.

ABSTRACTShort rotation coppice (SRC) willow is a second‐generation lignocellulosic energy crop with a background of research and breeding programmes carried out globally for more than three decades. While commercial standards include planting in mixtures of 6–8 willow genotypes of genetic diversity, much research to date has focused on monoculture trials. Research has found significant differences in willow performance through different management methods, soil properties and environmental interactions (GxE), when applied locally. However, global analysis of these interactions remains a challenge. We present a global SRC willow dataset to facilitate researchers and growers with a resource not available to date to help in closing the gap between research and industry. Data has been collected through literature review and personal communications with key researchers on willow in the United Kingdom. Global annual average yield is 9 Mg Dry Matter (DM) ha−1 year−1 with 17 genotypes, including two types of mixtures, above the economic threshold of 10 Mg DM ha−1 year−1. Canada and the United States are the best and worst performers with 10.6 and 6.7 Mg DM hr−1 year−1, respectively. We expect this dataset to provide an efficient way of estimating yields at a smaller scale by multiple combinations of GxE interactions. Biomass production from 1‐year‐old stems in the first harvest cycle is significantly lower than for the second and third year of the first harvest cycle (ANOVA, p < 0.001). Harvest cycles of 2 and 3 years did show significant but small differences in final yield (t = 3.87, p < 0.001). A random forest statistical procedure was applied to test for the association of the predictor variables with biomass production. The model explained up to 63.65% of the variance observed in yield for all genotypes and sites, with genetic diversity among the most important variables.

Utilisation of wood stove fuels produced by washing and torrefaction of short rotation coppice willow grown on contaminated land

Alley cropping agroforestry systems (ACS) integrate rows of trees with rows of crops, creating diverse cropping systems. This study compared the dry matter yields of two winter crops, i.e. winter wheat and winter oilseed rape, and two spring crops, i.e. silage maize and spring barley, in a temperate ACS that integrates rows of short rotation coppice trees with 48 m wide crop alleys with the yields of treeless open cropland as a function of tree height and distance from the tree row. Our study used generalised linear mixed effects models to analyse yield data generated in Wendhausen, northern Germany, from 2016 to 2024. Relative crop yields in the ACS were significantly reduced at a distance of 1 m from tree rows for all crops and at a distance of 4 m for silage maize, suggesting that competitive effects influencing yield are limited to a zone immediately adjacent to the tree rows. Mean relative ACS crop yields were always lower than those at the corresponding distances in the reference crop, except for maize at 24 m. Overall, tree height had a negative effect on the relative crop dry matter yield at 1 m from the tree row. A significant negative effect of increasing tree height on dry matter yield was only detected for spring barley, whereas no effect was observed for silage maize and winter wheat. If possible, poplar harvesting intervals should be adapted to prevent trees from growing too tall.

Pellets can be produced not only from forest dendromass but also from agricultural dendromass derived from short rotation coppice (SRC) plantations, as well as surplus straw from cereal and oilseed crops. This study aimed to determine the thermophysical properties and elemental composition of 16 types of pellets produced from four types of forest biomass (Scots pine I, alder, beech, and Scots pine II), four types of agricultural biomass (SRC willow, SRC poplar, wheat straw, and rapeseed straw), and eight types of pellets from mixtures of wood biomass and straw. Another aim of the study was to demonstrate which pellet types met the parameters specified in three standards, categorizing pellets into thirteen different classes. As expected, pellets produced from pure Scots pine sawdust exhibited the best quality. The quality of the pellets obtained from mixtures of dendromass and straw deteriorated with an increase in the proportion of cereal straw or rapeseed straw in relation to pure Scots pine sawdust and SRC dendromass. The bulk density of the pellets ranged from 607.9 to 797.5 kg m−3, indicating that all 16 pellet types met the requirements of all six classes of the ISO standard. However, it was determined that four types of pellets (rapeseed, wheat, and two others from biomass mixtures) did not meet the necessary requirements of the Premium and Grade 1 classes. The ash content ranged from 0.44% DM in pellets from pure Scots pine sawdust to 5.00% DM in rapeseed straw pellets. Regarding ash content, only the pellets made from pure Scots pine sawdust met the stringent requirements of the highest classes, A1, Premium, and Grade 1. In contrast, all 16 types of pellets fulfilled the criteria for the lower classes, i.e., Utility and Grade 4. Concerning the nitrogen (N) content, seven types of pellets met the strict standards of classes A1 and Grade 1, while all the pellets satisfied the less rigorous requirements of classes B and Grade 4.

Life cycle assessment of bioenergy production from short-rotation coppice plantation in Hungary

Abstract In times of insect decline, sampling programmes are fundamental for monitoring and protecting insect populations. Different types of traps are currently used for insect monitoring, which makes trap selection more challenging and impedes the comparability of results among methods. Trap comparisons, which reveal the species richness, complementarity and costs for the materials and operation of different trap types, help identify sampling designs that ensure (cost‐)efficient insect capture. For our study, we selected five sampling techniques for flying insects: canopy Malaise traps (CAMTs), caterpillar traps, branch sampling and white and blue pan traps. We compared them across four habitats (forest, margin and centre of short rotation coppices and maize fields) using detected Barcode Index Numbers (BINs). Comparisons were performed for the total arthropod community and separately for the Coleoptera, Diptera, Lepidoptera and Hymenoptera orders. Our trap selection demonstrated high complementarities of 66–77% depending on the habitat. Our findings indicate that, in most cases, CAMTs, branch sampling and caterpillar traps were the most effective and cost‐efficient options when used individually or in combination. Caterpillar traps were particularly effective in forests and detected far more taxa than only lepidopterans. Pan traps demonstrated the lowest species richness and poorest cost efficiency. Nevertheless, it is important to consider individual groups and habitats, such as Diptera, Coleoptera and maize fields, for which pan traps can also be an effective method.

As warm season droughts increase in frequency due to climate change, causing severe yield losses especially among cereal crops, European agriculture is in dire need of adaptation. While agroforestry is widely regarded as a key adaptation measure, little is known on how yield performance is influenced by changing water availability in temperate regions. Therefore, we assessed the yield dynamics of five winter crops (winter wheat, triticale, winter barley, winter pea, and rapeseed) during seven growing seasons (2012 to 2023) in a well-established (since 2007) alley cropping agroforestry trial site in Southwestern Germany. The trial integrated three different agroforestry practices in a randomized block design: (i) willow short-rotation coppice, (ii) walnut trees for nut production, and (iii) diverse hedgerows. The relationship between crop yield and climatic water balance was analyzed using a linear mixed-model. In this unique long-term comparison, we demonstrate that individual alley cropping practices exhibited distinct yield patterns with increased distance to tree rows. In contrast to the willow short rotation coppice, walnut and hedgerows did not evoke significant winter crop yield declines at proximity. While in the walnut plots yields did not significantly vary with distance to tree rows, yields adjacent to hedge rows declined significantly towards the alley center. Moreover, tree rows contributed to stable crop yields under fluctuating water availability in their proximity and up to the alley center on their leeward side while yields significantly varied with changing climatic water balance on the windward side. Our results underline the potential of agroforestry to sustain yields in the face of increasingly variable water availability, further substantiating the contribution of alley cropping agroforestry for farming systems’ resilience to increasingly variable weather conditions. They moreover contribute to planning and policy support for advancing agroforestry as a climate smart solution in temperate regions.

Model-based analysis of the impact of an eco-scheme premium on the climate protection potential of short rotation coppice in Baden-Württemberg

Mixing-in native thorny shrubs greatly improves the habitat quality of short rotation coppice strips within a modern agroforestry system for breeding birds

Silvoarable agroforestry systems (AFS) with short rotation coppice strips (CS) combine fast-growing trees with croplands, offering potential biodiversity benefits in agricultural landscapes. However, their actual impact on biodiversity remains underexplored. This study investigated the use of CS within a modern silvoarable AFS in northern Germany by large and medium-sized mammals in different seasons (winter, summer) and various tree strip variants (Conventional, Aspen, Ecological). A total of ten species were detected during camera trapping surveys, including farmland (European hare) and forest species (e.g. pine marten, wildcat) along with generalists (e.g. beech marten, raccoon). The European hare showed the highest activity (detected on nearly 90% of days in winter and on all days in summer), followed by roe deer (almost 40% of days in winter and 80% in summer) and red fox (about 60% resp. 40% of days in winter/summer), while most other species were detected sporadically or only in one season. Mammal activity was higher in summer than in winter, with minor differences between the tree strip variants in both seasons. The results indicate that CS in modern AFS are used by a wide range of mammal species and could especially benefit the threatened European hare, while potentially supporting forest species like the strictly protected wildcat with regard to woodland connectivity. However, this study does not provide information on the habitat function and quality of CS compared to other habitats like hedgerows. Therefore, and due to the spatial and temporal limitations of the study, there is a great need for further research on the use of CS by mammals.

Willow short rotation coppice. Energy and environmental assessment

Properties of Indonesian short rotation coppice (Calliandra calothyrsus) biochar as a coal substitute in the steelmaking process