Method for intercropping remediation of medium-low-concentration cadmium-arsenic composite polluted farmland soil by using pumpkin and Amaranthus mangostanus L

The invention discloses a method for intercropping remediation of medium-low-concentration cadmium-arsenic composite polluted farmland soil by using pumpkin and Amaranthus mangostanus L. The method comprises: planting pumpkin and Amaranthus mangostanus L in cadmium-arsenic-polluted farmland soil in an intercropping planting manner, wherein an intercropping plant line number ratio of pumpkin to Amaranthus mangostanus L is 1:2-3; during remediation, maintaining the field moist, and maintaining the soil moisture content at 58-80%; applying 250-550 kg of a compound fertilizer and 5500-7500 kg of an organic fertilizer on per hectare of the soil; after the pumpkin matures, simultaneously harvesting the pumpkin and the Amaranthus mangostanus L, and obtaining the pumpkin fruits; and transferring the roots, the stems and the leaves of the pumpkin and the whole Amaranthus mangostanus L out of the field, and carrying out sanitary landfill or being used as a garden and park composting raw materialso as to transfer heavy