Land use change in Heihe catchment on loess tableland based on CA-Markov model

Studying the land use changes in the Loess Plateau can provide important information for decision-making of ecologic construction. Using CA-Markov (Celluar Automata) model, the trend, rate, type of land use change from 1985 to 2000 and their relations with terrain in the Heihe watershed in the tableland-gully region of the Loess Plateau were analyzed, and the land use scenario in 2015 was simulated. Results showed that farmland and medium density grassland were the dominant land use types. Forest and farmland decreased, grassland and construction land increased while other land use types changed little from 1985 to 2000. The major transformation types were mutual conversion between forest and grassland, and farmland conversion to other land use types. Land use changes mainly occurred in the gully regions. The simulated result by CA-Markov model indicated that each land use type from 2000 to 2015 would keep the change trend from 1985 to 2000. Therefore, it is urgent to protect farmland, impel the Grain for Green Project and promote regional sustainable development.