uid=KBS,o=lter,dc=ecoinformatics,dc=orgalluid=sbohm,o=lter,dc=ecoinformatics,dc=orgallpublicreadhttps://lter.kbs.msu.edu/datasets/24.emlNicholasHaddadMichigan State University

3700 E Gull Lake DriveHickory Corners49060US

haddad@kbs.msu.edu0000-0002-1591-9322StaceyVanderWulpMichigan State University

3700 East Gull Lake DriveHickory CornersMI49060US

(269) 671-2339(269) 671-2333vanderws@msu.eduprincipal contactG.RobertsonMichigan State University

3700 East Gull Lake DriveHickory CornersMI49060US

(269) 760-8364(269)671-2351robert30@msu.edu0000-0001-9771-9895original investigator2026-10-05

original data source http://lter.kbs.msu.edu/datasets/24

LTERKBSKellogg Biological StationHickory CornersMichiganGreat LakessoilnitrogennitrateammoniumcationsanionsinorganicnutrientsagricultureInorganic NutrientsDisturbanceLTER Core Research Areaanions nitrate inorganic nutrients soil cations nitrogen ammonium agriculturefarmingbiotahttps://apps.usgs.gov/thesaurus/thesaurus-full.php?thcode=15Data in the KBS LTER core database may not be published without written permission of the lead investigator or project director. These restrictions are intended mainly to preserve the primary investigators' rights to first publication and to ensure that data users are aware of the limitations that may be associated with any specific data set. These restrictions apply to both the baseline data set and to the data sets associated with specific LTER-supported subprojects.All publications of KBS data and images must acknowledge KBS LTER support.The areas around the Kellogg Biological Station in southwest Michigan-85.404699-85.36685742.42026542.3910191989-01-012022-01-01Kellogg Biological StationData Managerlter.data.manager@kbs.msu.eduhttp://lter.kbs.msu.edu02vkce854KBS LTERAmmonium (NH4 ) and nitrate (NO3-) are the predominate forms of inorganic N in soils; their availability affects rates of N transformation, plant uptake, and N leaching. To measure the nutrient pool of NH4 and NO3- in soils, a subsample of a fresh, sieved composite sample is extracted, filtered, and the extract then analyzed using colorimetric techniques. Concentrations of NH4+ and NO3- are typically expressed as element mass of N per gram of dry soil, but conversion to an areal basis is possible if the soil bulk density and sample depth are known. Sampling frequency: Depends on experiment, time of year, and research objective. Soil inorganic N is routinely measured as part of our LTER and GLBRC soil sampling programs.Data Managerhttp://lter.kbs.msu.edu/protocols/33Composite soil samples are made by physically mixing individual soil cores taken within a specific area into one homogenous sample. Compositing reduces the number of analyses to be performed and is designed to provide a representative sample of the area or treatment. Soils of the Main Cropping System Experiment (MCSE) are sampled throughout the growing season by taking soil cores at each of 5 sampling stations per plot. Samples are then composited by plot. Composite samples are sieved and then subsampled for soil moisture and inorganic N analysis, and annually subsampled for determination of N mineralization potential. Samples may also be subsampled for other analyses as requested by various investigators. Sampling frequency: minimum of once per month throughout the growing season (March–November), typically biweekly from April–September.Data Managerhttp://lter.kbs.msu.edu/protocols/188The nitrogen mineralization potential of soils is an estimate of the net production of inorganic N under given conditions and provides a means to assess soil N availability. To measure in situ N mineralization potentials subsamples of a sieved, composite soil sample are placed in polyethylene bags, reburied in the field, incubated for 21 days (short-term), retrieved and resampled for soil inorganic N. Polyethylene bags allow diffusion of oxygen but not moisture. The N mineralization potential is the difference between the final and the initial total inorganic N (nitrate + ammonium) concentration and is expressed on a gravimetric basis (microgram N/g dry soil/day), which can be converted to an areal basis (microgram N/m2/day) if the soil bulk density is known. Sampling frequency: Depends on experiment and research objective. N mineralization potential is measured once annually (since 1996) as part of our soil sampling program of the LTER Main Cropping System Experiment, less frequently than earlier in the project.Data Managerhttp://lter.kbs.msu.edu/protocols/34programNational Science Foundationhttp://dx.doi.org/10.13039/100000001DEB 2224712https%3A%2F%2Fnsf.gov%2Fawardsearch%2FshowAward%3FAWD_ID%3D2224712%26HistoricalAwards%3Dfalsehttps://lter.kbs.msu.edu/datatables/53Kellogg Biological Station LTER: Soil Inorganic Nitrogen by Treatment (KBS021-001)Average concentrations of nitrate (NO3-N) and ammonium (NH4-N), expressed as micrograms N per gram dry soil, in surface soils (0-25 cm) of MCSE treatments. Treatment averages are derived from datatable KBS021-002.Soil+Inorganic+Nitrogen+by+Treatment.csvNone281\ncolumn,no"\https://lter.kbs.msu.edu/datatables/53.csvYearYear in which the date occursYYYY11987-4-18CampaignThe sampling campaignThe sampling campaignsample_datedate of samplingYYYY-MM-DD11987-4-18Treatmenttreatmenttreatmentsub_plotthe sub_plot if any. On T3 and T4 these are mainly the strip plots 'ST'the sub_plot if any. On T3 and T4 these are mainly the strip plots 'ST'Nitratesoil nitrate pool averaged within treatment across replicatesmicrogramsPerGramrealAmmoniumsoil ammonium pool averaged within treatment across replicatesmicrogramsPerGramrealtop_depth_cmtop depth of the soil sample measured from the soil surfacecentimeterrealbottom_depth_cmbottom depth of the soil sample as measured from the soil surfacecentimeterrealhttps://lter.kbs.msu.edu/datatables/55Kellogg Biological Station LTER: Soil Inorganic Nitrogen (KBS021-002)Concentration of nitrate (plus nitrite) and ammonium (in micrograms N per gram dry soil) in surface soil (0-25 cm) samples, composited by replicate (R1-R6) for all MCSE treatments. Since 2019, also includes samples collected 3-4 times over the growing season from T3 and T4 sampling stations (1-5) and prairie strips (ST).Soil+Inorganic+Nitrogen.csvNone371\ncolumn,no"\https://lter.kbs.msu.edu/datatables/55.csvYearyear in which the date occursYYYY11987-4-18Campaignsampling effort with which the data is associatedsampling effort with which the data is associatedDatedate of soil samplingYYYY-MM-DD11987-4-18Treatmentmain LTER treatmentmain LTER treatmentReplicatereplicate blockreplicate blockstationstation id if the samples were not compositedstation id if the samples were not compositedsub_plotThe treatment sub_plot. The prairie strips (ST) in T3 and T4The treatment sub_plot. The prairie strips (ST) in T3 and T4dry_soil_gdry soil weight used in the extractiongramrealsolution_mlml of KCL solutionmilliliterrealno3_ppmmeasured NO3-N concentration in solution (ppm)milligramsPerLiterrealnh4_ppmmeasured NH4-N concentration in solution (ppm)milligramsPerLiterrealNitratesoil extractable nitrate plus nitrite, as N (average of analytical replicates, screened for outliers and corrected for soil moisture)microgramsPerGramrealAmmoniumsoil extractable ammonium, as N (average of analytical replicates, screened for outliers and corrected for soil moisture)microgramsPerGramrealtop_depth_cmtop depth of the soil sample as measured from the soil surfacecentimeterrealbottom_depth_cmbottom depth of the soil sample as measured from the soil surfacecentimeterrealhttps://lter.kbs.msu.edu/datatables/56Kellogg Biological Station LTER: Soil Nitrogen Mineralization (KBS021-004)Net nitrogen mineralization, nitrification and ammonification potentials of surface soils (0-25 cm) for all MCSE treatments, as determined by changes in nitrate and ammonium content over short term (~21 days) field incubations of subsamples from composite soil samples. Since 2019, also includes samples collected from T3 and T4 sampling stations (1-5) and prairie strips (ST).Soil+Nitrogen+Mineralization.csvNone331\ncolumn,no"\https://lter.kbs.msu.edu/datatables/56.csvYearyear in which the initial sample date occursYYYY11987-4-18Campaigneffort with which the sample is associatedeffort with which the sample is associatedTreatmenttreatmenttreatmentDescriptionTreatment descriptionTreatment descriptionReplicatereplicate blockreplicate blockstationsample station if sampled by stationsample station if sampled by stationsub_plotsub plot (ie main plot as indicated by an empty string or the prairie strip as indicated by 'ST')sub plot (ie main plot as indicated by an empty string or the prairie strip as indicated by 'ST')T0_Datedate on which the soil sample was initially analyzedYYYY-MM-DD11987-4-18T21_Datedate on which the buried sample was retrievedYYYY-MM-DD11987-4-18NetNitrificationdifference in nitrate levels (final minus the initial nitrate), divided by duration of the incubation. A positive sign means that there is more nitrate at the end of the incubation than at the beginning.microgramsPerGramPerDayrealNetMineralizationdifference in nitrate + ammonium levels (final - initial nitrate + ammonium), divided by duration of the incubation. A positive sign means that there is more nitrogen at the end of the incubation than the beginning.microgramsPerGramPerDayrealNetAmmonificationthe difference in ammonium levels (final - initial) devided by the duration of the incubation. A positive value means that there was more ammonium at the end of the incubation than at the beginning.microgramsPerGramPerDayreal@article{citation_3835, author = {Sarah Cusser and Christie A Bahlai and Scott M Swinton and G Philip Robertson and Nick M Haddad}, title = {Long-term research needed to avoid spurious and misleading trends in sustainability attributes of no-till}, year = {2020}, journal = {Global Change Biology}, pages = {3715-3725}, volume = {26}, doi = {10.1111/gcb.15080} } @article{citation_3572, author = {I Gelfand and I Shcherbak and N Millar and A N Kravchenko and G P Robertson}, title = {Long-term nitrous oxide fluxes in annual and perennial agricultural and unmanaged ecosystems in the upper Midwest USA}, year = {2016}, journal = {Global Change Biology}, pages = {3594-3607}, volume = {22}, doi = {10.1111/gcb.13426} } @article{citation_3572, author = {I Gelfand and I Shcherbak and N Millar and A N Kravchenko and G P Robertson}, title = {Long-term nitrous oxide fluxes in annual and perennial agricultural and unmanaged ecosystems in the upper Midwest USA}, year = {2016}, journal = {Global Change Biology}, pages = {3594-3607}, volume = {22}, doi = {10.1111/gcb.13426} }