uid=KBS,o=lter,dc=ecoinformatics,dc=orgalluid=sbohm,o=lter,dc=ecoinformatics,dc=orgallpublicreadhttps://lter.kbs.msu.edu/datasets/226.emlG.RobertsonMichigan State University

3700 East Gull Lake DriveHickory CornersMI49060US

(269) 760-8364(269)671-2351robert30@msu.edu0000-0001-9771-9895StephenHamiltonMichigan State University

3700 East Gull Lake DriveHickory CornersMI49060

(269) 671-2231(269)671-2104hamilton@msu.edu0000-0002-4702-90172026-08-19

original data source http://lter.kbs.msu.edu/datasets/226

LTERKBSKellogg Biological StationHickory CornersMichiganGreat LakesleafareaindexLAIfoliagedensityfarmingbiotahttps://apps.usgs.gov/thesaurus/thesaurus-full.php?thcode=15This information is released under the Creative Commons license - Attribution - CC BY (https://creativecommons.org/licenses/by/4.0/). The consumer of these data ("Data User" herein) is required to cite it appropriately in any publication that results from its use. The Data User should realize that these data may be actively used by others for ongoing research and that coordination may be necessary to prevent duplicate publication. The Data User is urged to contact the authors of these data if any questions about methodology or results occur. Where appropriate, the Data User is encouraged to consider collaboration or co-authorship with the authors. The Data User should realize that misinterpretation of data may occur if used out of context of the original study. While substantial efforts are made to ensure the accuracy of data and associated documentation, complete accuracy of data sets cannot be guaranteed. All data are made available "as is." The Data User should be aware, however, that data are updated periodically and it is the responsibility of the Data User to check for new versions of the data. The data authors and the repository where these data were obtained shall not be liable for damages resulting from any use or misinterpretation of the data. Thank you.Creative Commons Attribution 4.0 Internationalhttps://creativecommons.org/licenses/by/4.0/CC-BY-4.0The areas around the Kellogg Biological Station in southwest Michigan-85.404699-85.36685742.42026542.391019Kellogg Biological StationData Managerlter.data.manager@kbs.msu.eduhttp://lter.kbs.msu.edu02vkce854KBS LTERThe Leaf Area Index (LAI) is a measurement of the amount of foliage in a plant canopy and is often incorporated into studies on primary production, water and nutrient use, carbon balance, and understory development. The LAI 2000 Plant Canopy Analyzer by LI-COR, Inc. calculates LAI from light measurements taken above and below the canopy with a “fish-eye” optical sensor which simultaneously measures light interception at five zenith angles. LAI is then computed using a model of radiative transfer and is reported as m2 m-2 (area of leaves per unit area of ground). In 2012, we started using an LAI AccuPAR LP-80 Ceptometer. In order to compare these measurements with those from the LAI 2000 Plant Canopy Analyzer, we made simultaneous measurements with both instruments, including across-row and along-row measurements for corn and soybean, in fall 2012 and throughout 2013. These data are available for comparison in the datatable at https://data.sustainability.glbrc.org/datatables/312. Frequency: depends on research purpose; we measured LAI every two weeks throughout the growing season in Block 1 (R1) for all treatments of the GLBRC Biofuel Cropping System Experiment (BCSE).Data Managerhttp://lter.kbs.msu.edu/protocols/118The Leaf Area Index (LAI) is a measurement of the amount of foliage in a plant canopy and is often incorporated into studies on primary production, water and nutrient use, carbon balance, and understory development. LAI is often used in models as an index of canopy biomass and hence aboveground production. We started using the LAI AccuPAR LP-80 Ceptometer in 2012. In order to compare and convert our previous measurements with the LAI 2000 Plant Canopy Analyzer, we made simultaneous measurements with both instruments in fall 2012 and various times throughout 2013. These comparisons included across-row as well as along-row measurements for corn and soybean. For along-row measurements, the ceptometer sensor array was placed at such an angle that it crossed the space between rows, but did not cross a row. These data are available in the datatable at https://data.sustainability.glbrc.org/datatables/312. Starting in 2014, LAI measurements were made with a ceptometer only. The concurrent point/ceptometer measurements may be used to convert previous point measurements to ceptometer measurements. Frequency: depends on research purpose; we measured LAI every two weeks throughout the growing season in Block 1 (R1) for all treatments of the GLBRC Biofuel Cropping System Experiment (BCSE).Data Managerhttp://lter.kbs.msu.edu/protocols/167Board of Regents of the University of Wisconsin System, operating as University of Wisconsin-Madison, Madison, WIprogramU.S. Department of Energyhttp://dx.doi.org/10.13039/100000015DE-SC0018409https%3A%2F%2Fpamspublic.science.energy.gov%2FWebPAMSExternal%2FInterface%2FCommon%2FViewPublicAbstract.aspx%3Frv%3Dadb8e0e1-b281-416b-9ad7-18f5a6f94739%26rtc%3D24%26PRoleId%3D10https://lter.kbs.msu.edu/datatables/312Kellogg Biological Station LTER: Leaf Area Index (LAI) (GLBRC082-007)Leaf Area Index (LAI) measurements for all BCSE treatments (G1-G10) at KBS. From 2009 to 2013, LAI was measured with a Licor LAI-2000 meter and from 2013 to 2017 with an AccuPar LP-80 Ceptometer. Dual measurements using both meters were conducted in 2013 in order to compare results.Leaf+Area+Index+(LAI).csvNone391\ncolumn,no"\https://data.sustainability.glbrc.org/datatables/312.csvsample_datetimedate and time of measurement, the plus sign indicates the time relative to Universal Coordinated Time (UCT).YYYY-MM-DD hh:mm:ss+hh11987-4-18local_datetimethe time in the eastern time zone either standard time or daylight saving time depending on the date.YYYY-MM-DD hh:mm:ss11987-4-18treatmentexperimental treatmentexperimental treatmentreplicatereplicate nested within treatmentreplicate nested within treatmentdirectiondirection and plant numberdirection and plant numberlaileaf area indexmeterSquaredPerMeterSquaredrealselstandard error of laimeterSquaredPerMeterSquaredrealdifnfraction of sky visiblenumberrealmtamean tilt angledegreeintegersemstandard error of MTAdegreeintegersmpnumber of sample pairs usednumberintegercommentsnotes about the data rownotes about the data rowinstrumentthe instrument used to measure LAIthe instrument used to measure LAImean_above_parmean PAR above the canopy in micromoles/(m^2 s)micromolePerMeterSquaredPerSecondrealmean_below_parmean PAR below the canopy in micromoles/(m^2 s)micromolePerMeterSquaredPerSecondrealtauratio between the above and below canopy PARdimensionlessrealchi(leaf distribution parameter): ratio of the projected area of an average canopy element (a leaf, for example) on a horizontal plane to its projection on a vertical plane; the default value for χ is 1.0, which assumes the canopy angle distribution to be spherical.dimensionlessrealfb (fractional beam radiation): ratio of direct beam radiation coming from the sun to radiation gathered from all ambient sources, like the atmosphere, or reflected from other surfacesdimensionlessrealzenith_angleangle between the point in the sky directly overhead vertical, called the zenith (0°), and the position of the sun. The angle is calculated based on the global position, time of day, and locationdegreereal