A regional assessment of land‐based carbon mitigation potentials: Bioenergy, BECCS, reforestation, and forest management

Abstract

Land-based solutions are indispensable features of most climate mitigation scenarios. Here we conduct a novel cross-sectoral assessment of regional carbon mitigation potential by running an ecosystem model with an explicit representation of forest structure and climate impacts for Bavaria, Germany, as a case study. We drive the model with four high-resolution climate projections (EURO-CORDEX) for the representative concentration pathway RCP4.5 and present-day land-cover from three satellite-derived datasets (CORINE, ESA-CCI, MODIS) and identify total mitigation potential by not only accounting for carbon storage but also material and energy substitution effects. The model represents the current state in Bavaria adequately, with a simulated forest biomass 12.9 ± 0.4% lower than data from national forest inventories. Future land-use changes according to two ambitious land-use harmonization scenarios (SSP1xRCP2.6, SSP4xRCP3.4) achieve a mitigation of 206 and 247 Mt C (2015-2100 period) via reforestation and the cultivation and burning of dedicated bioenergy crops, partly combined with carbon capture and storage. Sensitivity simulations suggest that converting croplands or pastures to bioenergy plantations could deliver a carbon mitigation of 40.9 and 37.7 kg C/m 2 , respectively, by the year 2100 if used to replace carbon-intensive energy systems and combined with CCS. However, under less optimistic assumptions (including no CCS), only 15.3 and 12.2 kg C/m 2 are mitigated and reforestation might be the better option (20.0 and 16.8 kg C/m 2 ). Mitigation potential in existing forests is limited (converting coniferous into mixed forests, nitrogen fertilization) or even negative (suspending wood harvest) due to decreased carbon storage in product pools and associated substitution effects. Our simulations provide guidelines to policy makers, farmers, foresters, and private forest owners for sustainable and climate-benefitting ecosystem management in temperate regions. They also emphasize the importance of the CCS technology which is regarded critically by many people, making its implementation in the short or medium term currently doubtable. K E Y W O R D S afforestation, BECCS, climate mitigation, land management, land-use change, negative emissions | 347 KRAUSE Et Al.

Putting Bioenergy With Carbon Capture and Storage in a Spatial Context: What Should Go Where?

“…The spatial resolution of BECCS studies has increased over time with the development and popularization of high spatial resolution mapping of the technology. Most high spatial resolution studies opt to use small spatial blocks, ranging from 1 to 2 km, to differentiate resources within the countries (Donnison et al, 2020;Krause et al, 2020;Rosa et al, 2021). The Freer et al (2021) study is currently the only geospatial analysis BECCS study that has achieved a higher spatial resolution down to the plot of land.…”

Accounting for forest management in the estimation of forest carbon balance using the dynamic vegetation model LPJ-GUESS (v4.0, r9710): implementation and evaluation of simulations for Europe

“…Historic monthly temperature, radiation, and precipitation data at 0.5 • × 0.5 • resolution were taken from the station-based CRU-NCEP climate dataset (Wei et al, 2014) and atmospheric CO 2 concentration data from the global carbon project (Le Quéré et al, 2018). Nitrogen deposition data for 1850-2009 were taken from Lamarque et al (2011). Simulations began with a 1300-year spin-up to initialise PNV species composition and soil and plant carbon pools.…”

“…Atmospheric CO 2 concentration data for 1850-2100 consistent with the CMIP5 GCM forcing were used. During a 1250year spin-up, the detrended 1850-1879 climate was recycled and the 1850 CO 2 and nitrogen deposition data (Lamarque et al, 2011) were used. After 2100, the 2071-2100 detrended climate data were recycled and the 2100 CO 2 data and the 2090-2099 nitrogen deposition data were used.…”

“…It has been used to estimate forest vulnerability to climate change (Seiler et al, 2015) and carbon mitigation potential of regrowth forests and forests under alternative management scenarios (Pugh et al, 2019;Krause et al, 2020). Earlier versions of LPJ-GUESS have been modified to enable analysis of clear-cut forest management and the effects of wind damage and insect outbreaks (Lagergren et al, 2012;Jönsson et al, 2012). In this study, we describe the implementation of expanded forest management capabilities including even-age and clear-cut as well as uneven-age and continuous-cover management in LPJ-GUESS v4.0.…”

Accounting for forest management in the estimation of forest carbon balance using the dynamic vegetation model LPJ-GUESS (v4.0, r9333): Implementation and evaluation of simulations for Europe

“…been used to estimate forest vulnerability to climate change (Seiler et al, 2015) and carbon mitigation potential of regrowth forests and forests under alternative management scenarios (Pugh et al, 2019;Krause et al, 2020). Earlier versions of LPJ-GUESS have been modified to enable analysis of clearcut forest management and the effects of wind damage and insect outbreaks (Lagergren et al, 2012;Jönsson et al, 2012). In this study, we describe the implementation of forest management capabilities in LPJ-GUESS v.4.0, which considers, in addition to detailed carbon-and water-cycle processes, nitrogen-cycling and nitrogen-limitation (Smith 70 et al, 2014).…”