Forest Growth and Dendrometer Monitoring

Dendrolog: Growth Heatmap

This view shows daily stem growth patterns of a selected logger tree (one tree per forest plot) as a year calendar heatmap, complemented by a compact daily precipitation panel for the same year.

Selection

• Plot (forest observation area)
• Single logger tree (tree_number)
• Metric:
  • Growth (daily_inc): Difference of mean diameter d_avg to the previous day – irreversible daily increment.
  • Amplitude (daily_amp): Daily range d_max − d_min – short‑term reversible elastic change (turgor / hydration).

Visualization

• Calendar heatmap: cell color encodes growth or amplitude (robust scale using 5–95% percentiles).
• Precipitation: daily bars below the heatmap for meteorological context.
• Functions: year chips for selection; export PNG (heatmap) and CSV (growth/amplitude + rain).

Use Cases

• Phenology (start/end of growing season, growth pulses)
• Linking rainfall events to rehydration and growth
• Stress diagnostics (high amplitude with low growth may indicate water deficit)
• Data quality (missing days, outliers become visible)
• Multi‑year comparison (drought years, extremes)

Summary: The heatmap makes daily growth dynamics and weather context quickly interpretable for diagnostics, monitoring, and reporting.

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Dendrolog: Stem Elasticity

This view compares, per plot, two components of stem diameter over the full available time span:

• Irreversible Growth (Baseline): long‑term increment (derived via sliding minimum window, then monotonized).
• Elastic Component (Stem Elasticity / Turgor): short‑term reversible fluctuations (difference d_avg − baseline).

Shown Elements

• Two lines per plot (solid baseline, dashed elastic; same color).
• Legend: toggle each series (baseline / elastic per plot).
• Time window: slider dataZoom (x‑axis fixed to global min/max).
• Export: PNG (chart) and CSV (time series incl. tree cohort used).

Aggregation

• Per tree: baseline + elasticity; terminal jump artefacts removed.
• Per plot: daily trimmed mean (20% each side) over a dynamic cohort:
  • Trees must cover ≥90% of days; if too few, best coverage trees added until min. 2.
  • Intersection of common days ensures constant cohort composition.

Use Cases

• Assess seasonal / inter‑annual turgor and hydration dynamics.
• Compare growth vs. short‑term water reactions between plots (max. 2 simultaneously).
• Detect drought stress (high elasticity with low baseline; delayed recovery after rain).
• Monitoring, diagnostics, reporting, and quality assurance of logger data.