The results showed that the basic cultivated farmland (17.59 104 hectares) in the whole city can be divided into 6 grades, among which the IFI (Integrated fertility index) of the cultivated land at the first grade was bigger than 0.85. Its area was 2.07 104 hectares, accounting for 11.8% of total cultivated area.
Our study indicates that the model can be applied to study the interaction between land surface processes and atmospheric boundary layers over various underlying surfaces and their regional climate effects.
Regularities of wind-erosion of different land-use types in Yongding River sandy land, Beijing
The threshold wind velocity of a number of variables was studied in four different land-use types: farm land, forestland, wild grassland and a flood plain in the Yongding River sandy land in Beijing.
The following conclusions were drawn: 1) The order of decreasing threshold of wind speed for sand displacement and surface roughness were forestland, wild grassland, farm land, sparse wild grassland and flood plain.
At a height of 0-20 cm, the height increased while the sediment discharge percent of sand flux decreased; there were significant differences in the sand flow formation under different land-use types.