Device and method for analyzing mechanical properties of soil under action of plant root system

The invention discloses a device and a method for analyzing mechanical properties of soil under the action of a plant root system. The device comprises a cultivation container and a cultivation control system, a water permeable plate is arranged in the cultivation container, and a casing pipe for cultivation is arranged on the water permeable plate; the cultivation control system comprises a first water level sensor, a temperature sensor, a timer, a controller, a first electromagnetic valve, a second electromagnetic valve, a third electromagnetic valve, a water pumping device, a nutrient solution pumping device, a water tank, a nutrient solution tank and a heating piece; and an infusion hose is arranged on the cultivation container. The invention also provides a method for testing by adopting the analysis device. The method comprises the following steps: cultivating a root-soil complex sample, taking out the root-soil complex sample, carrying out a triaxial compression test, carrying out a direct shear test a