QGIS · Thurston Garden, Suva · Coursework, USP

A thematic map of tree health and leaf density in Thurston Garden, Suva. The job was to put two attributes on one sheet without making the garden unreadable.

Data

The survey came as a CSV: species, coordinates, health, leaf density, canopy size. I imported it into QGIS as a point layer, set the CRS, and checked the attribute table before any symbology.

Two variables on one map

Health is colour. Leaf density is size.

Health — Healthy green. Moderate yellow. Poor orange. Damaged red.

Leaf density started as text. I added a numeric field, LeafDensityNum: Sparse = 1, Moderate = 2, Dense = 3. QGIS could then scale the points. Sparse stays small. Dense reads from across the sheet.

White outlines and a little opacity keep the points clear of the basemap.

Basemap and boundary

Satellite underlay was too busy. I switched to CartoDB Positron so the colours carry the map. I digitised the garden edge as a polygon: transparent fill, green outline, so the study area is obvious.

Layout

Print Layout holds the title, legend, scale, north arrow, CRS, sources, author line, and a locator map in the lower right. The locator is quiet — no labels — so it only says where Suva sits.

What I would keep

Colour plus size on one point layer. A pale basemap. A drawn boundary. Fewer labels. That is enough for a garden this size.