Quadrat

[1][2] A quadrat is suitable for sampling or observing plants, slow-moving animals, and some aquatic organisms.

The systematic use of quadrats was developed by the pioneering plant ecologists Roscoe Pound and Frederic Clements between 1898[4] and 1900.

[9] A quadrat can be used by researchers to methodically count organisms within a smaller, representative area in order to extrapolate to a larger habitat when comprehensive sampling is impossible or not practical.

To avoid selection bias, researchers randomly distribute quadrats throughout the sampling area.

Methods of precisely relocating the area of study vary widely in accuracy and include measurement from nearby permanent markers, use of total station theodolites, consumer-grade GPS, and differential GPS.

A quadrat used to measure the percentage cover of certain species
Botanist and students examining the species distribution using a quadrat