Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Forest carbon sequestration and climate change
Document related concepts
no text concepts found
Transcript
Forest carbon sequestration and climate change Dr Brian Tobin University College Dublin Overview • • • • • Sequestration –what is it & why important? Role of forests in climate change CARBiFOR research project Forest biomass and carbon Role of afforestation & sequestration Context: Climate change –increasing rate driven by anthropogenic emissions • Increasing atmospheric carbon dioxide concentration • leading to global warming No longer any doubt –proof all around us Carbon sequestration Proof of global warming! The net removal from the atmosphere of carbon dioxide, and storage in plant biomass (e.g. in the form of increasing forests or in other reservoirs such as soil, geological formations, oceans, wood products, etc.) Photosynthesis – Respiration = Sequestration Tree growth Solar radiation Carbon dioxide Oxygen Water Carbon dioxide Nutrients Wood/Timber Mitigation of climate change? To decrease sources and increase sinks! Options: • Renewable energy • Energy efficiency & conservation • Nuclear power • Transport, urban planning and design • Carbon air capture, CCS and scrubbers in factory chimney stacks • Societal and population control • Reforestation and avoided deforestation • Forest carbon sequestration Role of forests in climate change mitigation: • Sequestration in new forest stocks (5 pools) • Conservation of existing forests (avoiding degradation and deforestation) • HWP stock pool (life span important) • Energy source (carbon neutral) • Substitution for other fossil fuels Harvested Wood Products Climate change & Irish forestry Impacts •Species distribution / suitability •Productivity •Pests and diseases •Frequency of extreme climatic events Understanding of effects required before suitable adaptive strategies can be developed Species suitability Black et al., 2010 Species suitability Black et al., 2010 CARBiFOR • Carbon sequestration in Irish Forest ecosystems • Common species, typical of commercial forestry • Chronosequence approach • Focus on the ecosystem Web: http://www.ucd.ie/carbifor/index.html Ecosystem approach Measuring forest productivity Eddy covariance Biomass sampling Soil sampling Litter collection sampling Respiration chambers Chronosequence of sites Biomass Sampling • Sample trees: ‐ Stem Different components or tissue types ‐ ‐ ‐ ‐ Bark Dead branches Live Foliage Roots • Component samples used to determine: Moisture content, basic density and carbon content Root Excavation: Biomass distribution Per tree… Biomass allocation (% dry biomass) to tree components across the chronosequence. Carbon fraction Tree Component Total tree Root Stem wood Bark Branches Dead branches Needles Stem & Bark Foliage IPCC GPG default = 50% Mean 50.24 48.99 49.90 51.30 51.06 51.31 51.57 50.16 51.39 C-fraction (%) 95% Confidence interval 0.14 0.19 0.24 0.25 0.17 0.29 0.16 0.21 0.14 Forest ecosystem carbon balance Units of NEP: T C ha‐1 year‐1 5 carbon pools: • Aboveground • Belowground • Deadwood • Litter • Soil Black & Farrell, 2006 Other land‐uses Forests in Ireland • Forests cover 10% of total land area – Public 57%; Private 43% • Total stocked forest area 625,750 ha – Conifer 73.9% – Broadleaf 24.3% – Temporarily unstocked 1.8% • 2/3 of estate 20‐years‐old or less NFI, 2007 Carbon uptake in Irish forests • 6.2 MT CO2 ha per year (1.96 T CO2 per second) • Harvest removals 2.6 MT • Net removal from atmosphere of 3.6 MT CO2 • Kyoto forests ‐2.63 MT CO2 for 2010 (valued at €40M) BUT Sequestration through afforestation is finite, potentially short term, and reversible. One rotation 5 rotations After one rotation C‐sequestration reaches ± steady state. Therefore afforestation effect is once‐off Is it worth it??? Is it sustainable? Mitigation of emissions Sustainable? Bioenergy and products Forestry Commission, 2003 19 21 19 25 19 29 19 33 19 37 19 41 19 45 19 49 19 53 19 57 19 61 19 65 19 69 19 73 19 77 19 81 19 85 19 89 19 93 19 97 20 01 20 05 20 09 Annual afforestation (ha) Afforestation rates Age distribution of forest estate 25,000 Total 20,000 State Private 15,000 10,000 5,000 0 Dependant on afforestation rate Hendrick & Black, 2009 Conclusions Mitigation –forests contributing significantly Age distribution a challenge Adaptation required Anticipatory policy strategies Modelling of outcomes/senarios and climate change • Sustainable development across the industry (production and use of forest bio‐products) • • • • • Acknowledgments • COFORD • Coillte & private forest owners • CARBiFOR project team Thanks for your attention!
