Simulation of greenhouse gases following land-use change to bioenergy crops using the ECOSSE model : a comparison between site measurements and model predictions

This work contributes to the ELUM (Ecosystem Land Use Modelling & Soil Carbon GHG Flux Trial) project, which was commissioned and funded by the Energy Technologies Institute (ETI). We acknowledge the E-OBS data set from the EU-FP6 project ENSEMBLES (http://ensembles-eu.metoffice.com) and the data providers in the ECA&D project (http://www.ecad.eu).Peer reviewedPublisher PD

Establishment, growth and yield potential of the perennial grass Miscanthus x giganteus on degraded coal mine soils

BBS/E/W/10963A01Miscanthus x giganteus is a giant C4 grass native to Asia. Unlike most C4 species, it is relatively cold tolerant due to adaptations across a wide range of altitudes. These grasses are characterized by high productivity and low input requirements, making them excellent candidates for bioenergy feedstock production. The aim of this study was to investigate the potential for growing Miscanthus on extremely marginal soils, degraded by open lignite (brown coal) mining. Field experiments were established within three blocks situated on waste heaps originating from the lignite mine. Analyses were conducted over the first 3 years following Miscanthus cultivation, focusing on the effect of organic and mineral fertilization on crop growth, development and yield in this extreme environment. The following levels of fertilization were implemented between the blocks: the control plot with no fertilization (D0), a plot with sewage sludge (D1), a plot with an identical amount of sewage sludge plus one dose of mineral fertilizer (D2) and a plot with an identical amount of sewage sludge plus a double dose of mineral fertilizer (D3). Crop development and characteristics (plant height, tillering, and biomass yield [dry matter]) were measured throughout the study period and analyzed using Analysis of Variance (ANOVA). Significant differences were apparent between plant development and 3rd year biomass production over the course of the study (0.964 kg plant-1 for DO compared to 1.503 kg plant-1 for D1). Soil analyses conducted over the course of the experiment showed that organic carbon levels within the soil increased significantly following the cultivation of Miscanthus, and overall, pH decreased. With the exception of iron, macronutrient concentrations remained stable throughout. The promising yields and positive effects of Miscanthus on the degraded soil suggests that long term plantations on land otherwise unsuitable for agriculture may prove to be of great environmental and economic significancepublishersversionPeer reviewe

Consensus, uncertainties and challenges for perennial bioenergy crops and land-use

Perennial bioenergy crops have significant potential to reduce greenhouse gas (GHG) emissions and contribute to climate change mitigation by substituting for fossil fuels; yet delivering significant GHG savings will require substantial land-use change, globally. Over the last decade, research has delivered improved understanding of the environmental benefits and risks of this transition to perennial bioenergy crops, addressing concerns that the impacts of land conversion to perennial bioenergy crops could result in increased rather than decreased GHG emissions. For policymakers to assess the most cost-effective and sustainable options for deployment and climate change mitigation, synthesis of these studies is needed to support evidence-based decision making. In 2015, a workshop was convened with researchers, policymakers and industry/business representatives from the UK, EU and internationally. Outcomes from global research on bioenergy land-use change were compared to identify areas of consensus, key uncertainties, and research priorities. Here, we discuss the strength of evidence for and against six consensus statements summarising the effects of land-use change to perennial bioenergy crops on the cycling of carbon, nitrogen and water, in the context of the whole life-cycle of bioenergy production. Our analysis suggests that the direct impacts of dedicated perennial bioenergy crops on soil carbon and nitrous oxide are increasingly well understood and are often consistent with significant life cycle GHG mitigation from bioenergy relative to conventional energy sources. We conclude that the GHG balance of perennial bioenergy crop cultivation will often be favourable, with maximum GHG savings achieved where crops are grown on soils with low carbon stocks and conservative nutrient application, accruing additional environmental benefits such as improved water quality. The analysis reported here demonstrates there is a mature and increasingly comprehensive evidence base on the environmental benefits and risks of bioenergy cultivation which can support the development of a sustainable bioenergy industry

Breeding progress and preparedness for mass‐scale deployment of perennial lignocellulosic biomass crops switchgrass, miscanthus, willow and poplar

UK: The UK‐led miscanthus research and breeding was mainly supported by the Biotechnology and Biological Sciences Research Council (BBSRC), Department for Environment, Food and Rural Affairs (Defra), the BBSRC CSP strategic funding grant BB/CSP1730/1, Innovate UK/BBSRC “MUST” BB/N016149/1, CERES Inc. and Terravesta Ltd. through the GIANT‐LINK project (LK0863). Genomic selection and genomewide association study activities were supported by BBSRC grant BB/K01711X/1, the BBSRC strategic programme grant on Energy Grasses & Bio‐refining BBS/E/W/10963A01. The UK‐led willow R&D work reported here was supported by BBSRC (BBS/E/C/00005199, BBS/E/C/00005201, BB/G016216/1, BB/E006833/1, BB/G00580X/1 and BBS/E/C/000I0410), Defra (NF0424) and the Department of Trade and Industry (DTI) (B/W6/00599/00/00). IT: The Brain Gain Program (Rientro dei cervelli) of the Italian Ministry of Education, University, and Research supports Antoine Harfouche. US: Contributions by Gerald Tuskan to this manuscript were supported by the Center for Bioenergy Innovation, a US Department of Energy Bioenergy Research Center supported by the Office of Biological and Environmental Research in the DOE Office of Science, under contract number DE‐AC05‐00OR22725. Willow breeding efforts at Cornell University have been supported by grants from the US Department of Agriculture National Institute of Food and Agriculture. Contributions by the University of Illinois were supported primarily by the DOE Office of Science; Office of Biological and Environmental Research (BER); grant nos. DE‐SC0006634, DE‐SC0012379 and DE‐SC0018420 (Center for Advanced Bioenergy and Bioproducts Innovation); and the Energy Biosciences Institute. EU: We would like to further acknowledge contributions from the EU projects “OPTIMISC” FP7‐289159 on miscanthus and “WATBIO” FP7‐311929 on poplar and miscanthus as well as “GRACE” H2020‐EU.3.2.6. Bio‐based Industries Joint Technology Initiative (BBI‐JTI) Project ID 745012 on miscanthus.Peer reviewedPostprintPublisher PD

Modelling the impact of forest management and CO2-fertilisation on growth and demography in a Sitka spruce plantation

Abstract Afforestation and reforestation to meet ‘Net Zero’ emissions targets are considered a necessary policy by many countries. Their potential benefits are usually assessed through forest carbon and growth models. The implementation of vegetation demography gives scope to represent forest management and other size-dependent processes within land surface models (LSMs). In this paper, we evaluate the impact of including management within an LSM that represents demography, using both in-situ and reanalysis climate drivers at a mature, upland Sitka spruce plantation in Northumberland, UK. We compare historical simulations with fixed and variable CO2 concentrations, and with and without tree thinning implemented. Simulations are evaluated against the observed vegetation structure and carbon fluxes. Including thinning and the impact of increasing CO2 concentration (‘CO2 fertilisation’) gave more realistic estimates of stand-structure and physical characteristics. Historical CO2 fertilisation had a noticeable effect on the Gross Primary Productivity seasonal–diurnal cycle and contributed to approximately 7% higher stand biomass by 2018. The net effect of both processes resulted in a decrease of tree density and biomass, but an increase in tree height and leaf area index