Changes in version 0.1.0 (2026-03-23)                  

Initial CRAN release

New functions

Validation

  - validate_soil_data() — checks a data frame for missing columns,
    negative values, missing rows, and implausible year values before
    passing it to any analysis function.

Tillage analysis

  - summarise_tillage() — computes year × field summary statistics
    including number of operations, mean depth, maximum depth, total
    depth, and dominant operation type.
  - tillage_depth_trend() — calculates the year-on-year change in mean
    tillage depth per field and classifies each year as "baseline",
    "increasing", "decreasing", or "stable".
  - detect_compaction() — estimates compaction risk ("high", "moderate",
    "low") and plow pan depth from tillage records, using a
    user-specified depth threshold (default 20 cm).

Erosion analysis

  - track_erosion_depth() — tracks annual erosion depth, year-on-year
    change, and cumulative erosion loss per field; classifies trend as
    "baseline", "improving", "worsening", or "stable".
  - estimate_soil_loss() — estimates soil loss in t/ha using a standard
    mass-balance formula with an optional slope correction via the
    McCool et al. (1987) simplified LS factor: LS = (slope% / 9)^0.6.
  - compare_fields() — produces a wide-format year-by-year comparison of
    erosion depth and organic matter between two or more fields,
    including absolute difference columns.

Visualisation

  - plot_tillage_timeline() — line plot of mean annual tillage depth by
    field.
  - plot_erosion_trend() — line plot of annual erosion depth by field,
    with an optional second panel showing cumulative erosion
    (show_cumulative = TRUE).
  - plot_om_trend() — line plot of soil organic matter (%) by field with
    a 3.5% reference line.
  - plot_tillage_erosion() — dual-panel ggplot2 figure comparing mean
    tillage depth and erosion depth side by side.

Built-in datasets

  - tillage_operations — 20-row hypothetical tillage records for Field_A
    and Field_B across 2018–2023 (6 variables).
  - erosion_profile — 12-row hypothetical annual erosion and soil health
    measurements for the same fields (8 variables).

References

  - Lal, R. (2001). Soil degradation by erosion. Land Degradation and
    Development, 12(6), 519–539. https://doi.org/10.1002/ldr.472
  - McCool, D. K. et al. (1987). Revised slope steepness factor for the
    USLE. Transactions of the ASAE, 30(5), 1387–1396.
    https://doi.org/10.13031/2013.30576
  - Renard, K. G. et al. (1997). Predicting Soil Erosion by Water: A
    Guide to Conservation Planning with the Revised Universal Soil Loss
    Equation (RUSLE). USDA Agriculture Handbook No. 703.