Plant Leaf Area Index Meter

Plant Leaf Area Index Meterintroduction

Leaf area meter/The plant canopy image analyzer is used for the study of plant canopies at various heights, utilizing fisheye lenses andCCDThe image sensor obtains images of the plant canopy, and through analysis software, relevant indicators and parameters of the plant canopy are obtained. By using fisheye lens imaging to measure plant canopy data, only one operation is required, simplifying the complex work of traditional measurement methods that require multiple measurements at fixed points per day. Moreover, using image method to measure canopy can actively avoid canopy gaps that do not comply with the calculated canopy structure parameters, as well as obstacles that do not comply with measurement calculations.

Plant Leaf Area Index MeterTesting principles and methods

Leaf area meter/The plant canopy image analyzer adopts the principle of correlation between canopy porosity and canopy structure. It is based on the Beer's law of attenuation of light passing through a medium, and defines a series of assumptions for the plant canopy. Using a semi theoretical and semi empirical formula, the canopy structure parameters are calculated by measuring the canopy porosity. This is the principle currently used by various canopy instruments around the world. Under the above principle, the plant canopy image analyzer adopts the method of analyzing and measuring the canopy porosity of the hemisphere image under the canopy, which is the most accurate, labor-saving, time-saving, fast and convenient method among various methods.

structural composition

Leaf area meter/The plant canopy image analyzer is equipped with a fisheye image capture probe (using a fisheye lens and...)CCDImage sensor composition), built-in25aPARThe sensor consists of a measuring rod (rocker arm), a laptop, image acquisition software and image analysis software, and a high-capacity rechargeable battery pack. The fisheye probe is installed at the top of a very light rocker arm, which can obtain150Fish eye image with a viewing angle of degrees. The display and storage of images are completed by the configured laptop computer.

Features

Fish eye lens can automatically maintain a horizontal state: a small fish eye camera lens specially designed for measuring plant canopy structure is installed on a handheld universal balance joint, which can automatically maintain the lens in a horizontal state without the need for a tripod;

Fisheye lenses can be extended into the canopy: the lens is installed at one end of the rocker arm, and due to its small size and measuring rod, it can be easily extended horizontally or vertically to different heights of the canopy for rapid layered measurement, measuring the vertical distribution of light transmittance and leaf area index within the population;

Image analysis software: Image analysis software can define any image analysis area (zenith angle can be divided)10Zone, azimuth can be divided10District).

Can block unreasonable canopy parts: When conducting regional analysis of canopies in different directions, it is possible to arbitrarily block ground features and unreasonable canopy parts (such as missing plants, edge row problems, etc.). The selection of starting and ending angles for different zenith angles can avoid canopy pore conditions that do not comply with the calculation of canopy structure parameters. By manually adjusting the threshold, parameters such as leaf area index can be measured more accurately;

Measurable indicators

Leaf area index

Average inclination angle of blades

Sky scattered light transmittance

Plant canopy direct radiation transmittance at different solar altitude angles

Extinction coefficient of canopy at different solar altitude angles

Directional distribution of leaf area density

Main technical parameters

Camera angle:150°

Resolution:768×494pix

Measurement range: zenith angle is determined by0°～75°(150Fish eye lens)Can be divided into ten regions with azimuth angles360° can also be divided into ten regions

PARSensing range: sensing spectrum400nm～700nm

measurement range0～2000μmol/㎡•S

Analysis software: Plant canopy analysis system

electricity Source:8.4vRechargeable lithium battery pack

Probe size: diameter6cm, high10cm

total heavy Quantity:500gram(Excluding laptops)

Transmission interface:USB

Operating Temperature0～55℃