Carbon accretion in unthinned and thinned young-growth forest stands of the Alaskan perhumid coastal temperate rainforest.

BACKGROUND: Accounting for carbon gains and losses in young-growth forests is a key part of carbon assessments. A common silvicultural practice in young forests is thinning to increase the growth rate of residual trees. However, the effect of thinning on total stand carbon stock in these stands is uncertain. In this study we used data from 284 long-term growth and yield plots to quantify the carbon stock in unthinned and thinned young growth conifer stands in the Alaskan coastal temperate rainforest. We estimated carbon stocks and carbon accretion rates for three thinning treatments (basal area removal of 47, 60, and 73 %) and a no-thin treatment across a range of productivity classes and ages. We also accounted for the carbon content in dead trees to quantify the influence of both thinning and natural mortality in unthinned stands. RESULTS: The total tree carbon stock in naturally-regenerating unthinned young-growth forests estimated as the asymptote of the accretion curve was 484 (±26) Mg C ha-1 for live and dead trees and 398 (±20) Mg C ha-1 for live trees only. The total tree carbon stock was reduced by 16, 26, and 39 % at stand age 40 y across the increasing range of basal area removal. Modeled linear carbon accretion rates of stands 40 years after treatment were not markedly different with increasing intensity of basal area removal from reference stand values of 4.45 Mg C ha-1 year-1to treatment stand values of 5.01, 4.83, and 4.68 Mg C ha-1 year-1 respectively. However, the carbon stock reduction in thinned stands compared to the stock of carbon in the unthinned plots was maintained over the entire 100 year period of observation. CONCLUSIONS: Thinning treatments in regenerating forest stands reduce forest carbon stocks, while carbon accretion rates recovered and were similar to unthinned stands. However, that the reduction of carbon stocks in thinned stands persisted for a century indicate that the unthinned treatment option is the optimal choice for short-term carbon sequestration. Other ecologically beneficial results of thinning may override the loss of carbon due to treatment. Our model estimates can be used to calculate regional carbon losses, alleviating uncertainty in calculating the carbon cost of the treatments

Developing an input-output based method to estimate a national-level energy return on investment (EROI)

Concerns have been raised that declining energy return on energy investment (EROI) from fossil fuels, and low levels of EROI for alternative energy sources, could constrain the ability of national economies to continue to deliver economic growth and improvements in social wellbeing while undertaking a low-carbon transition. However, in order to test these concerns on a national scale, there is a conceptual and methodological gap in relation to calculating a national-level EROI and analysing its policy implications. We address this by developing a novel application of an Input-Output methodology to calculate a national-level indirect energy investment, one of the components needed for calculating a national-level EROI. This is a mixed physical and monetary approach using Multi-Regional Input-Output data and an energy extension. We discuss some conceptual and methodological issues relating to defining EROI for a national economy, and describe in detail the methodology and data requirements for the approach. We obtain initial results for the UK for the period 1997–2012, which show that the country’s EROI has been declining since the beginning of the 21st Century. We discuss the policy relevance of measuring national-level EROI and propose avenues for future research

Pilot study of rosiglitazone as an in vivo probe of paclitaxel exposure: Short report

To evaluate the use of rosiglitazone and the erythromycin breath test (ERMBT), as probes of CYP2C8 and CYP3A4, respectively, to explain inter-individual variability in paclitaxel exposure

Energy consumption-based accounts : A comparison of results using different energy extension vectors

Increasing attention has been focussed on the use of consumption-based approaches to energy accounting via input-output (IO) methods. Of particular interest is the examination of energy supply chains, given the associated risks from supply-chain issues, including availability shocks, taxes on fossil fuels and fluctuating energy prices. Using a multiregional IO (MRIO) database to calculate energy consumption-based accounts (CBA) allows analysts to both determine the quantity and source of energy embodied in products along the supply chain. However, it is recognised in the literature that there is uncertainty as to the most appropriate type of energy data that should be employed in an IO framework. Questions arise as to whether an energy extension vector should show where the energy was extracted or where it was used (burnt). In order to address this gap, we undertake the first empirical MRIO analysis of an energy CBA using both vectors. Our results show that both the energy-extracted and energy-used vectors produce similar estimates of the overall energy CBA for the UK—notably 45% higher than territorial energy requirements. However, at a more granular level, the results show that the type of vector that should be employed ultimately depends on the research question that is considered. For example, the energy-extracted vector reveals that just 20% of the UK's energy CBA includes energy extracted within the UK, an issue that is upmost importance for energy security policy. At the other end, the energy-used vector allows for the attribution of actual energy use to industry sectors, thereby enabling a better understanding of sectoral efficiency gains. These findings are crucial for users and developers of MRIO databases who undertake energy CBA calculations. Since both vectors appear useful for different energy questions, the construction of robust and consistent energy-used and energy-extracted extension vectors as part of commonly-used MRIO model databases is encouraged

Carbon accretion in unthinned and thinned young-growth forest stands of the Alaskan perhumid coastal temperate rainforest.

BACKGROUND: Accounting for carbon gains and losses in young-growth forests is a key part of carbon assessments. A common silvicultural practice in young forests is thinning to increase the growth rate of residual trees. However, the effect of thinning on total stand carbon stock in these stands is uncertain. In this study we used data from 284 long-term growth and yield plots to quantify the carbon stock in unthinned and thinned young growth conifer stands in the Alaskan coastal temperate rainforest. We estimated carbon stocks and carbon accretion rates for three thinning treatments (basal area removal of 47, 60, and 73 %) and a no-thin treatment across a range of productivity classes and ages. We also accounted for the carbon content in dead trees to quantify the influence of both thinning and natural mortality in unthinned stands. RESULTS: The total tree carbon stock in naturally-regenerating unthinned young-growth forests estimated as the asymptote of the accretion curve was 484 (±26) Mg C ha-1 for live and dead trees and 398 (±20) Mg C ha-1 for live trees only. The total tree carbon stock was reduced by 16, 26, and 39 % at stand age 40 y across the increasing range of basal area removal. Modeled linear carbon accretion rates of stands 40 years after treatment were not markedly different with increasing intensity of basal area removal from reference stand values of 4.45 Mg C ha-1 year-1to treatment stand values of 5.01, 4.83, and 4.68 Mg C ha-1 year-1 respectively. However, the carbon stock reduction in thinned stands compared to the stock of carbon in the unthinned plots was maintained over the entire 100 year period of observation. CONCLUSIONS: Thinning treatments in regenerating forest stands reduce forest carbon stocks, while carbon accretion rates recovered and were similar to unthinned stands. However, that the reduction of carbon stocks in thinned stands persisted for a century indicate that the unthinned treatment option is the optimal choice for short-term carbon sequestration. Other ecologically beneficial results of thinning may override the loss of carbon due to treatment. Our model estimates can be used to calculate regional carbon losses, alleviating uncertainty in calculating the carbon cost of the treatments

MOESM2 of Carbon accretion in unthinned and thinned young-growth forest stands of the Alaskan perhumid coastal temperate rainforest

Additional file 2: Appendix B. Estimating biomass for small trees

Who emits most? Associations between socio-economic factors and UK households' home energy, transport, indirect and total CO2 emissions

Does the association between household characteristics and household CO2 emissions differ for different areas such as home energy, transport and indirect emissions? This question is policy relevant because distributional implications of mitigation policies may vary depending on the area of emissions that is targeted if specific types of households are likely to have higher emissions in some areas than in others. So far, this issue has not been examined in depth in the literature on household CO2 emissions. Using a representative UK expenditure survey, this paper compares how household characteristics like income, household size, education, gender, worklessness and rural and urban location differ in their association with all three areas as well as total emissions. We find that these associations vary considerably across emission domains. In particular, whilst emissions in all areas rise with income, low income, workless and elderly households are more likely to have high emissions from home energy than from other domains, suggesting they may be less affected by carbon taxes on transport or total emissions. This demonstrates that fairness implications related to mitigation policies need to be examined for separate emission domains