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9. Evaluation of kinetic effects on clumped isotope fractionation (δ47) during inorganic calcite precipitation

Author

Tang, J, Dietzel, M, Fernandez, A, Tripati, AK, and Rosenheim, BE

Subjects
Geochemistry, Geology, Physical Geography and Environmental Geoscience, Geochemistry & Geophysics
Abstract

Considerable efforts have been made to calibrate the δ47 paleothermometer, which derives from the quantity of 13C-18O bonds in carbon dioxide produced during acid digestion of carbonate minerals versus its expected stochastic abundance, in a range of materials. However the impacts of precipitation rate, ionic strength, and pH on carbonate δ47 values are still unclear. Here we present a set of 75 measurements of δ47 values from inorganic calcites grown under well-controlled experimental conditions, where we evaluate the impact on δ47 values of precipitation rate (logR=1.8-4.4μmol/m2/h), pH (8.3-10.5; NBS pH scale), and ionic strength (I=35-832mM). With the data available and at the current instrumental resolution, our study does not resolve any clear effects of pH, ionic strength, growth rate effects on measured δ47 when compared in magnitude to the effects on δ18O over most of the ranges of parameters sampled by our analyses. If these relationships exist, they must be smaller than our current ability to resolve them within our dataset. Under our experimental conditions, a δ47-temperature equation, which is apparently insensitive to variation in pH, precipitation rate, and ionic strength over the range of variables sampled, can be written asδ47=(0.0387±0.0072)×106/T2+(0.2532±0.0829)(r2=0.9998,p=0.009)where δ47 values were reported on the absolute δ47 reference frame after normalizing to conventional 25°C reaction temperature using an acid fractionation factor of -0.00141-°C-1. © 2014 Elsevier Ltd.

Published
2014

20. Early AMD

Author

Dietzel, M., Pauleikhoff, D., Holz, F. G., Bird, A. C., Holz, Frank G., editor, Pauleikhoff, Daniel, editor, Spaide, Richard F., editor, and Bird, Alan C., editor

Published
2013
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48. The PROFOUND Database for evaluating vegetation models and simulating climate impacts on European forests

Author

Reyer, C.P.O., Silveyra Gonzalez, R., Dolos, K., Hartig, F., Hauf, Y., Noack, M., Lasch-Born, P., Rötzer, T., Pretzsch, H., Meesenburg, H., Fleck, S., Wagner, M., Bolte, A., Sanders, T.G.M., Kolari, P., Mäkelä, A., Vesala, T., Mammarella, I., Pumpanen, J., Collalti, A., Trotta, C., Matteucci, G., D'Andrea, E., Foltýnová, L., Krejza, J., Ibrom, A., Pilegaard, K., Loustau, D., Bonnefond, J.-M., Berbigier, P., Picart, D., Lafont, S., Dietzel, M., Cameron, D., Vieno, M., Tian, H., Palacios-Orueta, A., Cicuendez, V., Recuero, L., Wiese, K., Büchner, M., Lange, S., Volkholz, J., Kim, H., Horemans, J.A., Bohn, Friedrich, Steinkamp, J., Chikalanov, A., Weedon, G.P., Sheffield, J., Babst, F., Vega del Valle, I., Suckow, F., Martel, S., Mahnken, M., Gutsch, M., Frieler, K., Reyer, C.P.O., Silveyra Gonzalez, R., Dolos, K., Hartig, F., Hauf, Y., Noack, M., Lasch-Born, P., Rötzer, T., Pretzsch, H., Meesenburg, H., Fleck, S., Wagner, M., Bolte, A., Sanders, T.G.M., Kolari, P., Mäkelä, A., Vesala, T., Mammarella, I., Pumpanen, J., Collalti, A., Trotta, C., Matteucci, G., D'Andrea, E., Foltýnová, L., Krejza, J., Ibrom, A., Pilegaard, K., Loustau, D., Bonnefond, J.-M., Berbigier, P., Picart, D., Lafont, S., Dietzel, M., Cameron, D., Vieno, M., Tian, H., Palacios-Orueta, A., Cicuendez, V., Recuero, L., Wiese, K., Büchner, M., Lange, S., Volkholz, J., Kim, H., Horemans, J.A., Bohn, Friedrich, Steinkamp, J., Chikalanov, A., Weedon, G.P., Sheffield, J., Babst, F., Vega del Valle, I., Suckow, F., Martel, S., Mahnken, M., Gutsch, M., and Frieler, K.

Abstract

Process-based vegetation models are widely used to predict local and global ecosystem dynamics and climate change impacts. Due to their complexity, they require careful parameterization and evaluation to ensure that projections are accurate and reliable. The PROFOUND Database (PROFOUND DB) provides a wide range of empirical data on European forests to calibrate and evaluate vegetation models that simulate climate impacts at the forest stand scale. A particular advantage of this database is its wide coverage of multiple data sources at different hierarchical and temporal scales, together with environmental driving data as well as the latest climate scenarios. Specifically, the PROFOUND DB provides general site descriptions, soil, climate, CO2, nitrogen deposition, tree and forest stand level, and remote sensing data for nine contrasting forest stands distributed across Europe. Moreover, for a subset of five sites, time series of carbon fluxes, atmospheric heat conduction and soil water are also available. The climate and nitrogen deposition data contain several datasets for the historic period and a wide range of future climate change scenarios following the Representative Concentration Pathways (RCP2.6, RCP4.5, RCP6.0, RCP8.5). We also provide pre-industrial climate simulations that allow for model runs aimed at disentangling the contribution of climate change to observed forest productivity changes. The PROFOUND DB is available freely as a “SQLite” relational database or “ASCII” flat file version (at https://doi.org/10.5880/PIK.2020.006/; Reyer et al., 2020). The data policies of the individual contributing datasets are provided in the metadata of each data file. The PROFOUND DB can also be accessed via the ProfoundData R package (https://CRAN.R-project.org/package=ProfoundData; Silveyra Gonzalez et al., 2020), which provides basic functions to explore, plot and extract the data for model set-up, calibration and evaluation.

Published
2020

49. The Decreasing Prevalence of Nonrefractive Visual Impairment in Older Europeans: A Meta-analysis of Published and Unpublished Data

Author

Delcourt, C., Le Goff, M., von Hanno, T., Mirshahi, A., Khawaja, A. P., Verhoeven, V. J. M., Hogg, R. E., Anastosopoulos, E., Cachulo, M. L., Hohn, R., Wolfram, C., Bron, A., Miotto, S., Carriere, I., Colijn, J. M., Buitendijk, G. H. S., Evans, J., Nitsch, D., Founti, P., Yip, J. L. Y., Pfeiffer, N., Creuzot-Garcher, C., Silva, R., Piermarocchi, S., Topouzis, F., Bertelsen, G., Foster, P. J., Fletcher, A., Klaver, C. C. W., Korobelnik, J. -F., Acar, N., Azuara-Blanco, A., Berendschot, T., Bergen, A., Binquet, C., Bird, A., Bobak, M., Boon, C., Bretillon, L., Broe, R., Buitendijk, G., Capuano, V., Chakravarthy, U., Chan, M., Chang, P., Colijn, J., Cougnard-Gregoire, A., Cree, A., Cumberland, P., Cunha-Vaz, J., Daien, V., De Jong, E., Deak, G., Delyfer, M. -N., den Hollander, A., Dietzel, M., Erke, M. G., Faria, P., Farinha, C., Fauser, S., Finger, R., Foster, P., Gorgels, T., Grauslund, J., Grus, F., Hammond, C., Hansen, M., Helmer, C., Hense, H. -W., Hermann, M., Hoehn, R., Hogg, R., Holz, F., Hoyng, C., Jansonius, N., Janssen, S., Kersten, E., Khawaja, A., Klaver, C., Lamparter, J., Lechanteur, Y., Lehtimaki, T., Leung, I., Lotery, A., Mauschitz, M., Meester, M., Merle, B., Meyer zu Westrup, V., Midena, E., Mohan-Said, S., Mueller, M., Muldrew, A., Murta, J., Nickels, S., Nunes, S., Owen, C., Peto, T., Prokofyeva, E., Rahi, J., Raitakari, O., Rauscher, F., Ribeiro, L., Rougier, M. -B., Rudnicka, A., Randjvar, Sahel, Salonikiou, A., Sanchez, C., Schmitz-Valckenberg, S., Schouten, J., Schuster, A., Schweitzer, C., Segato, T., Shehata, J., Silvestri, G., Simader, C., Souied, E., Speckauskas, M., Springelkamp, H., Tapp, R., van Leeuwen, E., Verhoeven, V., Verzijden, T., Von Hanno, T., Vujosevic, S., Wiedemann, P., Williams, K., Yip, J., and Zerbib, J.

Subjects
Europe, Aged, Humans, Prevalence, Vision, Low, Visually Impaired Persons, Visual Acuity, Vision, Low
Abstract

TOPIC: To estimate the prevalence of nonrefractive visual impairment and blindness in European persons 55 years of age and older. CLINICAL RELEVANCE: Few visual impairment and blindness prevalence estimates are available for the European population. In addition, many of the data collected in European population-based studies currently are unpublished and have not been included in previous estimates. METHODS: Fourteen European population-based studies participating in the European Eye Epidemiology Consortium (n = 70 723) were included. Each study provided nonrefractive visual impairment and blindness prevalence estimates stratified by age (10-year strata) and gender. Nonrefractive visual impairment and blindness were defined as best-corrected visual acuity worse than 20/60 and 20/400 in the better eye, respectively. Using random effects meta-analysis, prevalence rates were estimated according to age, gender, geographical area, and period (1991-2006 and 2007-2012). Because no data were available for Central and Eastern Europe, population projections for numbers of affected people were estimated using Eurostat population estimates for European high-income countries in 2000 and 2010. RESULTS: The age-standardized prevalence of nonrefractive visual impairment in people 55 years of age or older decreased from 2.22% (95% confidence interval [CI], 1.34-3.10) from 1991 through 2006 to 0.92% (95% CI, 0.42-1.42) from 2007 through 2012. It strongly increased with age in both periods (up to 15.69% and 4.39% in participants 85 years of age or older from 1991 through 2006 and from 2007 through 2012, respectively). Age-standardized prevalence of visual impairment tended to be higher in women than men from 1991 through 2006 (2.67% vs. 1.88%), but not from 2007 through 2012 (0.87% vs. 0.88%). No differences were observed between northern, western, and southern regions of Europe. The projected numbers of affected older inhabitants in European high-income countries decreased from 2.5 million affected individuals in 2000 to 1.2 million in 2010. Of those, 584 000 were blind in 2000, in comparison with 170 000 who were blind in 2010. CONCLUSIONS: Despite the increase in the European older population, our study indicated that the number of visually impaired people has decreased in European high-income countries in the last 20 years. This may be the result of major improvements in eye care and prevention, the decreasing prevalence of eye diseases, or both.

Published
2018

50. Early AMD

Author

Dietzel, M., primary, Pauleikhoff, D., additional, Holz, F. G., additional, and Bird, A. C., additional

Published
2012
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