Data from: Strategic tillage of no-till decreased surface and subsurface losses of dissolved phosphorus
Data files
This dataset is embargoed and will be released on Jul 23, 2025 . Please contact Risto Uusitalo at if.ekul@olatisuu.otsir with any questions.
Lists of files and downloads will become available to the public when released.
Abstract
No-till is a cultivation practice in which plant seeds are applied in soil without completely breaking up the surface of agricultural fields as, e.g., in plowing. When growing annual crops, no-till is considered the most effective way of controlling erosion and associated nutrient losses to surface waters. The downside of long-term no-till, especially in soils with modest inherent erosion, is phosphorus (P) enrichment of the uppermost soil surface layer that causes an increase in dissolved P loss, i.e., the most potent fraction of P losses causing eutrophication of surface waters. As a remedy to dissolved P losses, occasional tillage, also termed strategic tillage, of long-term no-till fields has been suggested. We made strategic tillage of clay soil that has been under no-till management for a decade and measured surface and subsurface P losses during the following 4 yr. The study was made on a field, divided into four 0.5-ha plots, in SW Finland. Surface and subsurface (tile drainage) waters are collected and sampled for analyses flow-propositionally. These supplemental data contain a description of the field site and quarter-year sums of surface and subsurface discharges of water, dissolved P, particulate P, and total P. Also, the outcomes of statistical testing of the data are included. We found that strategic tillage effectively (by about 60%) decreased the losses of dissolved P via surface and subsurface discharge pathways. When the strategic tillage was done in summer and a new crop was sown a week later, erosion-associated particulate P losses only increased by about 10%. At the study site, strategic tillage was preferred over continuous no-till and annual plowing when searching for the least water eutrophication-fuelling tillage methods.
These datasets accompany the above publication, presenting details on the field setup, numbers behind the data presented in figures and statistical analyses, and details on statistical testing results. Files are ordered in four folders:
- Figures FigS1_FigS3 and captions:
-- FigS1 (jpg) shows the Jokioinen/Kotkanoja fields’s subsurface drainage layout, dimensions of the field, and a photo showing how flow-proportional water samples are collected
-- FigS2 (jpg) shows quarter-year sums of precipitation and mean air temperature during the study, number of successive days with at least 10 cm of snow cover each winter during the study, and maximum snow depth (with date)
-- FigS3 (jpg) presents the cumulative discharge of total P during the study; shown are surface, subsurface, and their summed losses
-- Figure captions (txt) explain data shown in the figures S1, S2, and S3 included in this folder - Weather data referred to in the article is not included here (due to conflicting license) but can be downloaded at the website of the Finnish Meteorological Institute: https://en.ilmatieteenlaitos.fi/download-observations (choose site: Jokioinen, Ilmala).
- Tables S5_S8 Water and P discharges:
-- Table S5 (CSV) gives quarter-year sums of surface and subsurface (tile drainage) water discharges from the four 0.5-ha plots during the study (2018-2022)
-- Table S6 (CSV) gives quarter-year sums of surface and subsurface losses of dissolved reactive phosphorus (DRP) from the field plots during the study
-- Table S7 (CSV) gives quarter-year sums of surface and subsurface losses of particulate phosphorus (PP) from the field plots during the study
-- Table S8 (CSV) gives quarter-year sums of surface and subsurface losses of total phosphorus (TP) from the field plots during the study - Tables S9_S11 Statistical testing:
-- Table S9 (CSV) shows differences in slope estimates for water discharge and P losses (summed surface and subsurface losses) during the control (Sept 2008 - May 2018) and study (Jul 2018 - Aug 2022) periods
-- Table S10 (CSV) lists slope estimates for water discharge and P losses (summed surface and subsurface losses) during the control (2008-2018) and study (2018-2022) periods
-- Table S11 (CSV) gives adjusted p-values of cross-comparisons of slope differences (Supplemental Table S10) in the control (2008-2018) and study (2018-2022) periods
Used units:
Precipitation and water discharges are given in mm
Temperatures are given in degrees Celsius
Phosphorus losses are given in grams per hectare
Description of the data and file structure
Weather data are linked with water and nutrient discharges as the study was conducted field-scale under natural precipitation. To obtain these data, go to https://en.ilmatieteenlaitos.fi/download-observations (site: Jokioinen, Ilmala).
Data are given as continuous quarter-year sums of water and P discharges for the period Sept 2008 to Aug 2022. These can be used, e.g., for the evaluation of phosphorus loss models.
Sharing/Access information
Weather data (not included in this zip file) were derived from the open database of the Finnish Meteorological Institute and their Jokioinen observatory located about 600 m from the study site. Other data were produced by the Natural Resources Institute Finland, Jokioinen unit.
The data are from a 2-ha field in SW Finland where surface and subsurface discharges are measured and sampled. In the field, three tillage options were applied: annual plowing, continuous no-till, and no-till that was plowed one time in the summer of 2018. Included in the data are discharge water volumes and P losses via surface and subsurface pathways during four years. The data are calculated as quarter-year sums from Aug 2018 to Aug 2022.