Hydrology — Canopy Processes What do we call the process by which precipitation is captured by a plant canopy and then returned to the atmosphere (without reaching the ground)?

Introduction / Context:
In the hydrologic cycle, not all precipitation that falls over vegetated terrain reaches the ground. Some is caught by leaves, branches, and stems and then evaporates directly back to the atmosphere. Quantifying this pathway is important in watershed water-balance studies and ecohydrology.

Given Data / Assumptions:

• Precipitation can be partitioned into interception, throughfall, and stemflow.
• The question specifies capture by canopy and subsequent return to atmosphere.
• We require the correct hydrologic term for that pathway.

Concept / Approach:
Interception is the fraction of precipitation retained on plant surfaces and lost via evaporation or sublimation without reaching the ground. Throughfall is precipitation that passes through the canopy (including drip) to the ground. Stemflow is water that runs down stems/trunks to the ground. Sublimation is a phase change (solid to vapor) and is not the canopy-capture process itself.

Step-by-Step Solution:

Verification / Alternative check:
Hydrology texts define interception loss as the evaporative loss from wetted canopies. Field methods (e.g., throughfall gauges) partition precipitation accordingly.

Why Other Options Are Wrong:

• sublimation: A phase change process; too general and not limited to canopy capture.
• stem flow: Water reaching ground via stems, not returned to atmosphere.
• throughfall: Water that reaches the ground through the canopy.

Common Pitfalls:
Confusing interception (a storage-and-evaporation process) with throughfall or stemflow (delivery processes to the ground surface).

Final Answer:
interception