This BrunnHafner_NewPhytologist2022_readme.txt file was generated on 2022-04-07 by Sarah J. Wright, edited by Benjamin D. Hafner on 2022-04-07, last updated by Sarah J. Wright on 2023-03-10 CHANGELOG Fixed 20230310 METHODOLOGICAL INFORMATION >> 2. Methods for processing the data: >> Exudates: Raw values in mg L-1 were multiplied by sample volume (40 mL) and normalised as per 24 hr (samples comprised of 48hrs of exudate collection). Blind control samples were then subtracted. The displayed exudation data are presented in ug C day-1. Replaces Exudates: Raw values in mg L-1 were multiplied by sample volume (40 mL) and normalised as per hr (samples comprised of 48hrs of exudate collection). Blind control samples were then subtracted. The displayed exudation data are presented in ug C hour-1. DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Ex_Roots_Properties.csv >> Variable List >> Npoc - non-purgeable organic carbon, ug d-1 replaces Npoc - non-purgeable organic carbon, ug hr-1 GENERAL INFORMATION 1. Title of Dataset: Data from: Carbon allocation to root exudates is maintained in mature temperate tree species under drought 2. Author Information Co-first authors: Benjamin D Hafner, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA (https://orcid.org/0000-0003-2348-9200) Melanie Brunn, iES Landau, Institute for Environmental Sciences, University of Koblenz-Landau, 76829 Landau, Germany (https://orcid.org/0000-0002-5692-8575) Co-authors: Marie J Zwetsloot, Soil Biology Group, Wageningen University, 6708 PB Wageningen, Netherlands (https://orcid.org/0000-0002-9392-213X) Fabian Weikl, Institute of Biochemical Plant Pathology, Helmholtz Zentrum München GmbH - German Research Center for Environmental Health, 85764 Neuherberg, Germany & Technical University of Munich, TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, 85354 Freising, Germany (https://orcid.org/0000-0003-3973-6341) Karin Pritsch, Institute of Biochemical Plant Pathology, Helmholtz Zentrum München GmbH - German Research Center for Environmental Health, 85764 Neuherberg, Germany (http://orcid.org/0000-0001-6384-2473) Kyohsuke Hikino, Technical University of Munich, TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, 85354 Freising, Germany (https://orcid.org/0000-0002-6981-3988) Nadine K Rühr, Institute of Meteorology and Climate Research – Atmospheric Environmental Research (IMK-IFU), Karlsruhe Institute of Technology (KIT), 82467 Garmisch-Partenkirchen, Germany ( https://orcid.org/0000-0001-5989-7463) Emma J Sayer, Lancaster Environment Centre, Lancaster University, LA1 4YQ Lancaster, UK (https://orcid.org/0000-0002-3322-4487) Taryn L Bauerle, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA ( https://orcid.org/0000-0003-2741-2593) 3. Date of data collection (range): 2019-05-26 - 2019-06-26 4. Geographic location of data collection (latitude, longiute, city, State, Country): N 48° 25.2’, E 11° 39.7’, Freising, Bavaria, Germany 5. Information about funding sources that supported the collection of the data: German Research Foundation (DFG), grant numbers: PR555/2-1, PR292/22-1, GR 1881/5-1, MA1763/7-1, MA1763/10-1 Bavarian State Ministry for Nutrition, Agriculture and Forestry and Bavarian State Ministry for Environment and Consumer Protection, grant number: W047/Kroof II. SHARING/ACCESS INFORMATION 1. Links to publications that cite or use the data: Melanie Brunn, Benjamin D Hafner, Marie J Zwetsloot, Fabian Weikl, Karin Pritsch, Kyohsuke Hikino, Nadine K Ruehr, Emma J Sayer, Taryn L Bauerle. (2022) Carbon allocation to root exudates is maintained in mature temperate tree species under drought. New Phytologist (in press) 2. Recommended citation for this dataset: Benjamin D Hafner, Melanie Brunn, Marie J Zwetsloot, Fabian Weikl, Karin Pritsch, Kyohsuke Hikino, Nadine K Ruehr, Emma J Sayer, Taryn L Bauerle. (2022) Data from: Carbon allocation to root exudates is maintained in mature temperate tree species under drought. [dataset] Cornell University eCommons Repository. https://doi.org/10.7298/6r80-8a15 DATA & FILE OVERVIEW 1. File List: BrunnHafner_Ex_Roots_Properties.csv - root characteristics (mass, tips, area) and exudation rates of sampled root branches. BrunnHafner_Soil_Moisture_KROOF.csv - volumetric soil moisture in 2 soil depth increments BrunnHafner_Root_Properties_KROOF.csv - root characteristics (mass, tips, area) and core volume of cores taken for tree level root area estimation BrunnHafner_Photosynthesis.csv - photosynthesis and stem respiration rates BrunnHafner_Soil_Respiration.csv - soil respiration rates BrunnHafner_Climate.csv - climate data (temperature, humidity and radiation) in 10 min intervals BrunnHafner_Rainfall.csv - precipitation data on a daily basis 2. Relationship between files, if important: Data were collected from the Kroof drought experiment. METHODOLOGICAL INFORMATION 1. Description of methods used for collection/generation of data: Data were collected from the Kroof drought experiment on six plots, three control (plots III, V and VII) and three drought (plots IV, VI and VIII) plots from two species, Fagus sylvatica L. and Picea abies (L.) Karst. in two soil depths (0-7 cm and 7-30 cm). The experimental setup of the KROOF experiment is described in detail in Grams T.E.E., Hesse B.D., Gebhardt T., Weikl F., Rötzer T., Kovacs B., … Pritsch K. (2021) The Kroof experiment: realization and efficacy of a recurrent drought experiment plus recovery in a beech/spruce forest. Ecosphere 12. https://doi.org/10.1002/ecs2.3399 Root exudates were sampled from individual root branches (1st–3rd order roots attached to a single transport root). Collected exudates were analysed for non-purgeable organic carbon (npoc) with a multi N/C 2100 S (Analytik Jena GmbH, Jena, Germany). Root mass, number of tips and root area (divided in total root area and root area ≤2 mm) were assessed with WinRhizo (WinRHIZO Pro 2016a, Regent Instruments Inc., Quebec, Canada). Soil moisture was measured with time-domain reflectometry probes TDR, (Campbell Scientific, Logan, USA) in vol-%. Fine-root biomass, surface area, and number of tips per plot were assessed using two soil cores (34 mm diameter) per species and plot in October 2018. Cores were divided into two depth increments. Fine roots (≤ 2 mm) were extracted from cores by washing with tap water and separated by species under a stereomicroscope. Fine roots were scanned and analysed for surface area and the number of tips using WinRhizo (WinRHIZO Pro 2016a, Regent Instruments Inc.), and subsequently dried to assess dry fine-root biomass. To quantify C assimilation, light-saturated (Photosynthetically active Photon Flux Density: 1500 umol m-2 s-1) gas exchange rates (Asat) were determined at 400 ppm carbon dioxide (CO2) concentration for two trees per species and plot using an open gas-exchange system (LI-6800, Li-Cor Inc., Lincoln, NE, USA) over two weeks in June 2019. Stem respiration (umol CO2 m-2 stem area and s-1) was measured using custom-built chambers (60-204 cm2) that were sealed to the stem at 1-m height with Terostat-IX (Henkel AG & Co. KGaA, Duesseldorf, Germany). Soil CO2 efflux (umol m-2 plot area and s-1) was measured via permanent soil collars (PVC pipe, 20-cm inner diameter, 12 cm height), which were inserted c. 2 cm deep into the soil (n = 1-3 per species and plot) with a multiplexed automated soil-chamber system (LiCor-8100M, LiCor Biosciences, Lincoln, NE, USA), and the daily sum was calculated per plot. Temperature and humidity were measured in 2m height and photosynthetically active radiation above the canopy in 10 min intervals. Rainfall data was collected daily above the canopy. 2. Methods for processing the data: Exudates: Raw values in mg L-1 were multiplied by sample volume (40 mL) and normalised as per 24 hr (samples comprised of 48hrs of exudate collection). Blind control samples were then subtracted. The displayed exudation data are presented in ug C day-1. Stem and soil respiration: Daily average values are displayed in umol m-2 s-1 3. Instrument- or software-specific information needed to interpret the data: All data analyses were done in R (version R 3.6.3) in the RStudio environment (version 1.2.1335). For specific testing the following packages were used: lme function in the nlme package; version 3.1-137; emmeans function in the emmeans package version 1.5.2-1; leveneTest function in the car package, version 2.1-2; optimize function in stats package, version 4.0.4 DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Ex_Roots_Properties.csv 1. Number of variables: 9 2. Number of cases/rows: 36 3. Variable List: Treatment - control/drought Plot - three control (plots III, V and VII) and three drought (plots IV, VI and VIII) plots Species - two species, Fagus sylvatica L. and Picea abies (L.) Karst Depth_increment - two soil depths, A (0-7 cm) and B (7-30 cm) Root_mass_g - dry root biomass, g Tips_n - number of root tips Root_area_total_cm2 - total root surface area, cm squared Root_area_fine_cm2 - Fine root (≤ 2 mm) surface area, cm squared Npoc - non-purgeable organic carbon, ug d-1 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Soil_Moisture_KROOF.csv 1. Number of variables: 6 2. Number of cases/rows: 24 3. Variable List: Date - format dd.mm.yy Treatment - control/drought Plot - three control (plots III, V and VII) and three drought (plots IV, VI and VIII) plots Species - two species, Fagus sylvatica L. and Picea abies (L.) Karst Depth_increment - two soil depths, A (0-7 cm) and B (7-30 cm) Soil_water_content - volumetric soil water content, vol-% 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Root_Properties_KROOF.csv 1. Number of variables: 8 2. Number of cases/rows: 48 3. Variable List: Treatment - control/drought Plot - three control (plots III, V and VII) and three drought (plots IV, VI and VIII) plots Species - two species, Fagus sylvatica L. and Picea abies (L.) Karst Depth_increment - two soil depths, A (0-7 cm) and B (7-30 cm) Core_volume_cm3 - volume of sampled soil core, cubic cm Root_mass_mg - dry root biomass, mg Tips_n - number of root tips Root_area_fine_cm2 - Fine root (≤ 2 mm) surface area, cm squared 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Photosynthesis.csv 1. Number of variables: 7 2. Number of cases/rows: 24 3. Variable List: Date - format dd.mm.yy Treatment - control/drought Tree_id - Identification of single tree numbers Plot - three control (plots III, V and VII) and three drought (plots IV, VI and VIII) plots Species - two species, Fagus sylvatica L. and Picea abies (L.) Karst Asat - Photosynthesis rate all measured between 8am - 3pm, umol m-2 s-1 Stem_respiration - Stem respiration rate as daily average, umol m-2 s-1 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Soil_Respiration.csv 1. Number of variables: 5 2. Number of cases/rows: 70 3. Variable List: Doy - Day of year in the year 2019 Treatment - control/drought Plot - three control (plots III, V and VII) and three drought (plots IV, VI and VIII) plots Species - two species, Fagus sylvatica L. and Picea abies (L.) Karst Soil_respiration - Soil respiration rate as daily average, umol m-2 s-1 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Climate.csv 1. Number of variables: 4 2. Number of cases/rows: 1426 3. Variable List: Date - format yyyy-mm-dd hh:mm:ss UTC Temperature - air temperature measured in 2m height, degree Celsius Relative_humidity - relative air humidity measured in 2m height, % Par - Photosynthetically active radiation measured above the canopy, umol m-2 s-1 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA DATA-SPECIFIC INFORMATION FOR: BrunnHafner_Rainfall.csv 1. Number of variables: 2 2. Number of cases/rows: 15 3. Variable List: Date - format dd.mm.yy Precipitation_mm - precipitation measured above the canopy, mm 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: NA