The effect of poplar-crop intercropping space on wheat growth and yield The influence of poplar-crop intercropping on crop nutrient compositions STUDY ON POPLAR GROWTH UNDER AGRO-SILVICULTURAL INTERCROPPING CONDITIONS THE STUDY ON SHADING EFFECT UNDER POPLAR-CROP INTERCROPPING SYSTEM A STUDY ON LIGHT UTILIZATION OF POPLAR-CROP INTERCROPPING SYSTEM Relationship between Crop Productivity and Ecological Factors in Poplar-Crop Intercropping Systems in Haihe Lowland Area The shading and its effect on crop yield under poplar-crop intercropping system A study on microclimate under poplar-crop intercropping systems