Agronomic Soil Chemistry — Switchgrass Nitrogen Fixation Experiment
Data in the KBS LTER core database may not be published without written permission of the lead investigator or project director Full terms of use
Agronomic chemistry of surface (0-25 cm) soils of the Switchgrass Nitrogen Fixation Experiment (plots 1-16) planted to switchgrass in 2016. Soils are occasionally collected in the fall (usually after harvest) for fertilizer and liming recommendations and analyzed for pH, lime index, phosphorus, potassium, calcium, magnesium, and cation exchange capacity by an analytical service laboratory.
This datatable is part of the Switchgrass Nitrogen Fixation Experiment dataset.
This dataset contains data from the Switchgrass Nitrogen Fixation Experiment established in 2016 after conversion of the historically tilled plots (1-16) of the Interactions Experiment from annual crops to switchgrass (Cave-in-rock). The experiment maintained the fertilizer treatment (fertilized and not fertilized) of the Interactions Experiment, but the tillage treatment was discontinued because switchgrass is a perennial crop that is not tilled. From 2018-2022, a rainout shelter experiment that also used buried mesocosms was conducted in the legacy no-till, no fertilizer plots (3, 6, 8, and 9) to examine the effect of soil wetting/drying regimes on the relationship between associative nitrogen fixation (ANF) and switchgrass phenology, diazotroph communities, and nifH expression. The experiment was retired after the 2022 growing season in order to establish the Switchgrass Biodiversity Experiment.
Note
| Experiment: | Switchgrass Nitrogen Fixation Experiment |
| Data available from: | October 2018 |
| Dataset: | KBS152 |
| Datatable ID: | KBS128-001.12 |
| Core Areas | Inorganic Nutrients |
| Repository link: | |
| Related Tables: | |
| Personnel: |
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| Last Updated | 2024-04-30 |
| Variate | Description | Units |
|---|---|---|
| sample date | sample date | |
| legacy tillage treatment | CT = Conventional tillage, NT = No-till, F = fertilized, N = unfertilized | |
| fertilization | F: fertilized; N: not-fertilized | |
| replicate | replicate block | |
| plot | whole plots (1-16), and plot id+MO (2, 6, 9, 13) stands for plots that have monoliths installed within. | |
| depth | depth of soil sampled | |
| pH | pH | |
| cec | cation exchange capacity (meq/100g) | meq/100g |
| phosphorus | Bray P1 phosphorus (ppm) | µg/kg |
| potassium | Potassium (ppm) | µg/kg |
| calcium | Calcium (ppm) | µg/kg |
| magnesium | Magnesium (ppm) | µg/kg |
| lime index | Lime Index | |
| comment | ||
| year | Sample year |
| Protocols |
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Data Excerpt
| sample_date | legacy_tillage_treatment | fertilization | replicate | plot | depth | ph | cec | phosphorus | potassium | calcium | magnesium | lime_index | comment | year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2018-10-15 | NT | F | 2.0 | 0-25 cm | 6.2 | 6.8891025 | 30.0 | 90.0 | 1015.0 | 190.0 | 70.0 | 2018.0 | ||
| 2018-10-15 | CT | N | 3.0 | 0-25 cm | 6.7 | 7.041282 | 37.0 | 85.0 | 1038.0 | 196.0 | 71.0 | 2018.0 | ||
| 2018-10-15 | CT | F | 1.0 | 0-25 cm | 6.0 | 5.844359 | 31.0 | 68.0 | 879.0 | 153.0 | 70.0 | 2018.0 | ||
| 2018-10-15 | CT | N | 2.0 | 0-25 cm | 6.5 | 6.749615 | 58.0 | 98.0 | 983.0 | 190.0 | 71.0 | 2018.0 | ||
| 2018-10-15 | NT | F | 4.0 | 0-25 cm | 6.2 | 5.931923 | 37.0 | 56.0 | 901.0 | 154.0 | 70.0 | 2018.0 |