Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
SU Wei-zhong1, YANG Gui-shan1, GU Chao-lin2
Under the background of globalization and informatization of the world economy, the
rapid economic growth and process of urbanization in Suzhou city in future will aggravate the
conservation pressure on cultivated land.It is time to consider and redefine the connotation of
current cultivated land conservation concept. ( 1)Based on domestic and foreign related researches
and the framework of PSR( Pressure-State-Response)model, this paper proposes the gradation
evaluation indicator system of cultivated land conservation in Suzhou city among which the
Pressure indicator is the environment pressure of cultivated land, and the State indicator is the
soil quality and land fragmentation, and the Response indicator is per unit area yield of grain.( 2)
Individual indicator evaluation results show that the environment pressure of cultivated land
caused by rapid population and economic growth, urban sprawl and freeway networks infrastructure
construction is very outstanding; the soil quality of cultivated land is very good, and the
land is fertile; the fragmentation is evident because of the division of urban, transport land,
lakes, rivers and highland terrain; the unit production ( 6683kg/ha) is higher than that of Jiangsu
Province ( 5954kg/ha) and the whole country ( 4399kg/ha) .( 3) The correlative analysis of these
individual indicators show that the correlative coefficient is very small, and the various
relationships between indicators are performed according to different regional characteristics, and
accordingly their weights are difficult to be defined.Based on the research result of correlative
analysis of indicators, the paper adopts the Hierarchical Cluster Analysis method for the general
gradation evaluation of cultivated land conservation.The results show that the ratio of the area of
the 4 ranks is 33.6 ∶32.4 ∶26.7 ∶7.3.The cultivated land of rank S1 is located in the rural areas
outside urbanization region and lake areas where four indicators are very good.The cultivated
land of rank S2 is located in the Yanjiang plains and the urbanized marginal areas where the soil
quality is good, and the level of food production is high.The cultivated land of rank S3 is
scattered in the urbanized marginal area and lake-hilly areas where four indicators are common.
The cultivated land of rank S4 is scattered in the areas around big cities and lakes hilly areas.
( 4) Then on the basis of regional characteristics and indicators relationships of each cultivated
land conservation rank, the gradation system of the 4 ranks is subdivided into 9 ranks, and some
conservation measures about cultivated land for each rank are also pointed out.