NATURAL RESOURCE MANAGEMENT • INTERACTIVE MODEL

🌳 Urban Green Cover Simulator

Explore how changes in urban green cover can influence estimated stormwater runoff and vegetation-related cooling services. Adjust the parameters and compare different urban scenarios.

⚙️ Simulation Parameters

Total Urban Area

Enter total study area in square metres.

Urban Green Cover

40%

Percentage of the study area covered by vegetation.

Rainfall Event

Rainfall depth for the selected event in millimetres.

📊 Simulation Results

Current scenario: 40% green cover over 100,000 m² during a 50 mm rainfall event.

🌿

GREEN AREA

40,000 m²

Area represented by urban vegetation

💧

ESTIMATED RUNOFF

3,000 m³

Modelled direct surface runoff

📉

RUNOFF REDUCTION

50%

Compared with 0% green cover baseline

🌡️

RELATIVE COOLING INDEX

0.64

Simplified vegetation-related indicator

📈 Green Cover vs Estimated Runoff

The orange point represents your selected green-cover scenario. Change the slider or rainfall value and run the simulation to see the point move and the curve update.

🔬 Scenario Comparison

The table compares several green-cover scenarios under the current urban area and rainfall conditions.

Green Cover	Green Area	Estimated Runoff	Runoff Reduction

🔎 Interpretation

Increasing green cover in the model decreases estimated surface runoff because vegetated areas are assigned a lower runoff coefficient than impervious urban surfaces. This illustrates one ecosystem-service function of urban vegetation: contributing to stormwater management. The model also represents vegetation-related cooling using a simplified relative indicator. It should not be interpreted as a direct prediction of actual air temperature.

🌍 Natural Resource Management Link

Urban vegetation is treated as a natural resource providing ecosystem services.
Green infrastructure can be considered alongside conventional urban drainage approaches.
Scenario modelling can help visualize possible consequences of changing land-cover composition.
The simulator demonstrates how environmental variables can be incorporated into a simple decision-support model.

🧮 Model Methodology

This simulator uses a simplified land-cover runoff model. The model separates the study area into vegetated and non-vegetated surfaces.

Rainfall volume
Rainfall volume = rainfall depth × study area

Weighted runoff coefficient
C = (green fraction × 0.20) + (non-green fraction × 0.80)

Estimated runoff
Runoff = rainfall volume × weighted runoff coefficient

For this educational model, runoff coefficients of 0.20 for vegetated surfaces and 0.80 for highly impervious surfaces are used as simplified assumptions. Actual coefficients vary with soil, vegetation, surface characteristics, rainfall intensity, slope and drainage conditions.

⚠️ Model Limitations

The model is a simplified educational simulation and is not a city-scale hydrological prediction.
Actual runoff depends on rainfall intensity and duration, soil infiltration, slope, drainage infrastructure and surface characteristics.
Different vegetation types and canopy structures can have different effects on urban microclimate.
The cooling indicator is illustrative and does not predict actual temperature reduction at a specific location.
The model does not represent spatial distribution of green areas, only their percentage of total study area.