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Basic Technical IVT Commonly tested

Leaf Area Index (LAI)

noun

Pronunciation: /liːf ˈɛəriə ˈɪndɛks/

The ratio of total leaf surface area to ground area occupied by a plant or plant community, expressed as a dimensionless number. LAI is a key structural parameter that determines light interception capacity and is significantly affected by stress-induced leaf loss.

Plain English

A measurement comparing total leaf area to the ground area a plant covers.

Etymology & History

Origin languageOld English, Latin, Latin
Rootleaf (foliage) + area (space) + index (indicator)
First recorded use1960s
Usage frequencyVery common

Usage

"Severe drought reduced leaf area index by 40%, limiting light capture and biomass production."

Style guide notes: Express LAI as dimensionless number; specify measurement method when comparing studies.

Also known as

leaf area ratio canopy density foliar coverage

Contrasted with

bare soil ratio senescent canopy

Related Terms

Frequently Asked Questions

What is a typical LAI value for healthy crop plants?

Healthy crops typically have LAI values between 3 and 6, varying by species and growth stage.

How does stress affect LAI measurements?

Stress-induced leaf senescence and abscission decrease LAI, reducing photosynthetic surface area and productivity.

Why Test Candidates on This?

Important agronomic measure for predicting crop productivity and assessing severity of environmental stress impacts.

Required skill level: Mid

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