The invention discloses a
pollution control and emission reduction method for farmland drainage. The
pollution control and emission reduction method comprises the following steps: arranging a
drainage ditch on the drainage side of the farmland, arranging a solidifying protective slope on the side slope of the
drainage ditch, planting hygrophyte on the protective slope, and arranging submerged alga plants inside the
drainage ditch; arranging
water level control gates inside the drainage
ditch in a segmented way and controlling the height of the
water level of each segment inside the drainage
ditch according to the field elevation change status; connecting a drainage river way at the downstream of the drainage
ditch, and arranging a flow division control valve at the connected part of the drainage ditch and the drainage river way, wherein the flow division control valve comprises a water inlet, an overflow port and a water
permeation hole, wherein a water
permeation tube is connected to the water
permeation hole; and the water permeation tube is embedded inside the
bank slope of the drainage river way. Compared with the prior art, the
pollution control and emission reduction method for farmland drainage effective retains and purify the draining water of the farmland, so that on one hand, the effect of
precipitation is exerted and the planted hygrophyte can also sufficiently absorb
nitrogen and
phosphorus contaminant ions in the water, and on other hand, the rice can use part of underground water due to elevation of the underground
water level to improve the utilization efficiency of the water.