A method of controlling the relative humidity in an environment and apparatus for accomplishing such method.

摘要

Method and apparatus are disclosed for controlling the relative humidity of a soil environment at a pre-set value using an enclosed volume (6) of a water-soluable or water-swellable material (14), said enclosed volume (6) separated from the external environment by a relatively stiff and strong semipermeable membrane (4) and separated from a pressurized irrigation water supply (36) by a water-impermeable constictable flexible section (8) or diaphragm in the supply line. When the soil is more moist than the pre-set value, intake of water through the membrane (4) causes expansion of the water-swellable material (14) which in turn contricts the flexible section (8) of the water supply line to interrupt the flow of water to the soil. When the soil mixture falls below the pre-set value, egress of water from the water-swellable material (14) releases the constricting force on the flexible section (8) thereby allowing increased flow of water through the flexible section (8) of supply line to the soil.