A method for monitoring slope lands and buildings on the slope lands
includes installing a light transceiver on a slope land and a light
emission device on a location or a building corresponding to the light
transceiver. When light emitted from the light emission device is
received by the light transceiver, the light transceiver does not output
signals. The light transceiver does not receive the light emitted from
the light emission device when the dislocation or inclination occurs to
the slope land and the light transceiver outputs a signal to alert a
monitor center.