Abstract:

The corn yield has much more relationship with the economic development， which will experience the period from low to high; and after the peak， it will become low. Households have different land use aims in different phases, showing the food first， the optimum of food and profit and profit ultimately. The food value of the land is super to any other land value to meet the food requirements of the family at the first phase. Household have no other means of production but the labour force. Household will introduce such extensive methods as increasing the sown area， reclaiming the margin arable land and decreasing the substance input. The main types of conversion is the land from the margin land to arable land; household will abandon the arable land to reclaim other margin land when they think the output of land is below the labor input. Households will keep the balance of food demand and the money pursuit at the second phase, in which they demand not only the food security but the money profit. Households will arrange the means of production such as labour forces， money and different proportion of land.And that leads to the increase of output ， the substitution of input and the increase of the economic cropping area . With the development of economic level， the cost of labor forces will increase. Households will make good use of the means of production. According to the return of different land use types, different land use types will keep balance under the conditions of equilibration of margin input and margin output; if not， transformation will occur. The arable land is maybe transformed into construction land. If the scale of food land is small， household will decrease the input or abandon the land to some extent. According to our analysis， households are experiencing the second phase in which they have enough food and work hard to make more money.

Key words: behavior of household, driving forces, intensive agricultural region, land use change