1 Ecological studies on Carya cathayensis and C.dabieshanensisOn Carya cathayensis: The environmental conditions were obviously different in Carya cathayensis distribution areas.Ecological factors, such as climate, soil, terrain and topography had significant influence on growth ,development,fruit yield and quality of C.cathayensis.Crude fat content in kernel of C.cathayensis elite trees was not closely related with readily available N,P,K and pH value of elite trees' soil, readily available P and pH valu...