The potential land productivity and population carrying capacity of Liling city were calculated by environmental elements step up method.The results showed that there was still a large potential land productivity and land developmental ability in Liling City;the potential productivity indices of rice,maize and peanut were 74.28%,86.52% and 84.94%,respectively,which have a large potential land productivity to develop.At the current level of land productivity,the land resources of Liling City can satisfy the demands of people and reach the well-off standard according to the regional food securit...