The concepts of minimum per capita cultivated area required,index of growing area size pressure and labor carrying capacity of land resources are put forward,and the amounts of surplus labor are computed for various counties.

This paper,helped by Excel software and based on the analysis of dynamic fluctuation of cropland,population and grain output since Henan Province opened to the outside world,analyzes variant characteristics of minimum cropland acreage per capita and pressure index on cropland.

By using regression analysis and prognostic theory,the minimum cropland acreage per capita,and cropland pressure index model were analyzed with the consideration of changes in cropland,population and grain output since enforcement of the reforming policy.

This paper discusses per-person cultivated land area of land expropriated unit, analyses the necessity of abolishing upper limit of compensation of land expropriation through mathematics model and contrastive analysis.

With the combination of GIS technology and remotely sensed data,cultivated land changing trend in regional scale can be easily traced and inventoried in time.

In Beijing, the cultivated land area has decreased from 456,040 ha in 1981 to 287,633 ha in 2001.