Enhanced woody biomass production in a mature temperate forest under elevated CO₂

Enhanced CO2 assimilation by forests as atmospheric CO2 concentration rises could slow the rate of CO2 increase if the assimilated carbon is allocated to long-lived biomass. Experiments in young tree plantations support a CO2 fertilization effect as atmospheric CO2 continues to increase. Uncertainty exists, however, as to whether older, more mature forests retain the capacity to respond to elevated CO2. Here we show, aided by tree-ring analysis and canopy laser scanning, that a 180-year-old Quercus robur L. woodland in central England increased the production of woody biomass when exposed to free-air CO2 enrichment (FACE) for seven years. Further, elevated CO2 increased exudation of carbon from fine roots into the soil with likely effects on nutrient cycles. The increase in tree growth and allocation to long-lived woody biomass, demonstrated here, substantiates the major role for mature temperate forests in climate change mitigation

Creating positive environmental impact through citizen science

Interest in citizen science is growing, including from governments and research funders. This interest is often driven by a desire for positive environmental impact, and the expectation that citizen science can deliver it by engaging the public and simultaneously collecting environmental data. Yet, in practice, there is often a gap between expected and realised impact. To close this gap, we need to better understand pathways to impact and what it takes to realise them. We articulate six key pathways through which citizen science can create positive environmental change: (1) environmental management; (2) evidence for policy; (3) behaviour change; (4) social network championing; (5) political advocacy; and (6) community action. We explore the project attributes likely to create impact through each of these pathways and show that there is an interplay between these project attributes and the needs and motivations of target participant groups. Exploring this interplay, we create a framework that articulates four citizen science approaches that create environmental impact in different ways: place-based community action; interest group investigation; captive learning research; and mass participation census

Revaluating forest drought experiments according to future precipitation patterns, ecosystem carbon and decomposition rate responses: a meta-analysis

Moisture availability is a strong determinant of decomposition rates in forests worldwide. Climate models suggest that many terrestrial ecosystems are at risk from future droughts, suggesting moisture limiting conditions will develop across a range of forests worldwide. The impacts of increasing drought conditions on forest carbon (C) fluxes due to shifts in organic matter decay rates may be poorly characterised due to limited experimental research. To appraise this question, we conducted a meta-analysis of forest drought experiment studies worldwide, examining spatial limits, knowledge gaps and potential biases. To identify limits to experimental knowledge, we projected the global distribution of forest drought experiments against spatially modelled estimates of (i) future precipitation change, (ii) ecosystem total above-ground C and (iii) soil C storage. Our assessment, involving 115 individual experimental study locations, found a mismatch between the distribution of forest drought experiments and regions with higher levels of future drought risk and C storage, such as Central America, Amazonia, the Atlantic Forest of Brazil, equatorial Africa and Indonesia. Decomposition rate responses in litter and soil were also relatively under-studied, with only 30 experiments specifically examining the potential experimental impacts of drought on C fluxes from soil or litter. We propose new approaches for engaging experimentally with forest drought research, utilising standardised protocols to appraise the impacts of drought on the C cycle, while targeting the most vulnerable and relevant forests

Furoic acid and derivatives as atypical dienes in Diels-Alder reactions

The furan Diels-Alder (DA) cycloaddition reaction has become an important tool in green chemistry, being central to the sustainable synthesis of many chemical building blocks. The restriction to electron-rich furans is a significant limitation of the scope of suitable dienes, in particular hampering the use of the furans most readily obtained from biomass, furfurals and their oxidized variants, furoic acids. Herein, it is shown that despite their electron-withdrawing substituents, 2-furoic acids and derivatives (esters, amides) are in fact reactive dienes in Diels-Alder couplings with maleimide dienophiles. The reactions benefit from a substantial rate-enhancement when water is used as solvent, and from activation of the 2-furoic acids by conversion to the corresponding carboxylate salts. This approach enables Diels-Alder reactions to be performed under very mild conditions, even with highly unreactive dienes such as 2,5-furandicarboxylic acid. The obtained DA adducts of furoic acids are shown to be versatile synthons in the conversion to various saturated and aromatic carbocyclic products

Outcomes of press-fit uncemented versus cemented hip arthroplasty in the oncologic patient

© 2020 Professor P K Surendran Memorial Education Foundation Background and objectives: Cemented hip arthroplasty is considered the standard of care for treating both osteoporotic femoral neck fractures and pathologic disease of the proximal femur due to the ability to achieve strong fixation in poor quality bone. There is minimal literature evaluating uncemented arthroplasty for pathologic disease of the proximal femur. This objective of this study is to compare outcomes of patients undergoing cemented and uncemented arthroplasty of the proximal femur for an oncologic indication. Methods: Patients who underwent hip arthroplasty procedures in one health system for an oncologic indication were identified. Demographics, cancer history, operative history, and complications were collected retrospectively. Harris Hip Scores (HHS) and Musculoskeletal Tumor Society Scores (MSTS) were prospectively collected via telephone. Results: 41 patients met criteria for review. 18 underwent cemented and 23 underwent uncemented arthroplasty. There were no significant differences in age, demographics, complications, 30-day mortality, intraoperative blood loss, transfusion requirements, average HHS, or average MSTS. Conclusion: No significant differences were found for patients undergoing hip arthroplasty for an oncologic indication regardless of whether or not the femoral component was cemented. Our results suggest that cemented and uncemented techniques are both safe and effective methods to be used at the oncologic surgeon\u27s discretion

Furoic acid and derivatives as atypical dienes in Diels-Alder reactions

The furan Diels-Alder (DA) cycloaddition reaction has become an important tool in green chemistry, being central to the sustainable synthesis of many chemical building blocks. The restriction to electron-rich furans is a significant limitation of the scope of suitable dienes, in particular hampering the use of the furans most readily obtained from biomass, furfurals and their oxidized variants, furoic acids. Herein, it is shown that despite their electron-withdrawing substituents, 2-furoic acids and derivatives (esters, amides) are in fact reactive dienes in Diels-Alder couplings with maleimide dienophiles. The reactions benefit from a substantial rate-enhancement when water is used as solvent, and from activation of the 2-furoic acids by conversion to the corresponding carboxylate salts. This approach enables Diels-Alder reactions to be performed under very mild conditions, even with highly unreactive dienes such as 2,5-furandicarboxylic acid. The obtained DA adducts of furoic acids are shown to be versatile synthons in the conversion to various saturated and aromatic carbocyclic products