| Row | E (Harvested) | F (Natural) | G (Total) | E+F-G |
|---|---|---|---|---|
| 12 | 183,322 | 5,366 | 188,688 | 0 |
Chapter 1 — Practice Demo Lab: Reference Solution
Lab: Inspect a real BC dataset together
Note
This is the reference solution for the Chapter 1 Practice Demo Lab (the five Tasks in Lab: Inspect a real BC dataset together). Use it to check your own attempt. The graded Canvas lab has its own private answer key — do not copy this into a Canvas submission.
Dataset: bc_disturbance_reforestation.xlsx (sheets About / ReadMe / Data). On the Data sheet the columns sit in these Excel columns: A Fiscal_Year, B Clearcutting_ha, C Clearcutting_with_reserves_ha, D Partial_cutting_ha, E Harvested_ha, F Natural_Disturbance_ha, G Total_Disturbance_ha, H Reforestation_ha. Data rows are 2–38 (row 1 is the header).
Task 1 — Inspect the workbook
- Where did the file come from? Environmental Reporting BC — Trends in Silviculture in B.C., published by the BC Ministry of Forests and distributed through the BC Data Catalogue. Licence: Open Government Licence — British Columbia.
- What does each column measure? One row per fiscal year; every area column is in hectares (ha).
Harvested_hais the total of the three cutting types (B+C+D);Total_Disturbance_hais harvest + natural disturbance (E+F);Reforestation_hais area reforested. - How many rows? 37 rows of data (fiscal years 1987–2023), 8 columns. (Read it off with
Ctrl+End, which jumps to the last cell, H38.)
Task 2 — Small data dictionary (two columns)
Example descriptions in plain language (yours may differ in wording):
| Column | Type | Unit | Description (own words) |
|---|---|---|---|
Reforestation_ha |
number | hectares | Area reforested (planted or naturally regenerated) in that fiscal year. |
Natural_Disturbance_ha |
number | hectares | Area disturbed by natural causes — fire, insects, wind — in that fiscal year. |
Compared with the ReadMe sheet, the meanings should match; the ReadMe may add that reforestation includes both planting and natural regeneration.
Task 3 — Compute a summary value (all three options worked)
Option A — Mean Reforestation_ha. Formula =AVERAGE(H2:H38) → 223,353 ha. Sanity check: must fall between MIN (189,394) and MAX (274,616) — it does. ✔
Option B — Maximum Natural_Disturbance_ha and its year. =MAX(F2:F38) → 218,275 ha; the year with =INDEX(A2:A38, MATCH(MAX(F2:F38), F2:F38, 0)) → 2017 (the record BC wildfire season). Sanity check: equals the single largest value in the column and is ≥ every other row. ✔
Option C — Total Harvested_ha. =SUM(E2:E38) → 7,364,971 ha. Sanity check: at least as large as MAX(E2:E38) (251,557) and never negative — it is. ✔
Task 4 — Verify one formula
Pick any data row — take row 12 (fiscal year 1997). The identity is Harvested_ha + Natural_Disturbance_ha = Total_Disturbance_ha, so =E12 + F12 - G12 should return 0.
The result is 0 (allowing a hectare of rounding), so the file is internally consistent for that row. A quick TRUE/FALSE version: =ROUND(E12+F12,0)=ROUND(G12,0) → TRUE.
Task 5 — Submit
Hand in one of: a one-page worksheet with your group’s answers to Tasks 1–4, or a screenshot of the Data sheet showing your formulas — with all group members’ names. (In the graded Canvas lab, follow the Canvas submission instructions instead.)