Abstract:

By integrated use of the transfer matrix of land use, land-use change atlas model, the dynamic correction methods of ecosystem services value model, the changes of grain output and ecosystem service value profit and loss caused by the change of arable land utilization in major grain-producing areas were measured from 2000 to 2018, and the main arable land use change types restricting the promotion of grain output and ecologial service abilities was figured out, and a targeted optimization path was proposed. The results showed that, the arable land area in major grain-producing areas showed the spatial differentiation of “north increased and south reduced” and the quantity change of “reduced more than increases”. The net transfer of arable land was 205.98×10⁴ hm², and construction land was the main type of arable land transfer. The output effects of arable land use change could be divided into four types, namely, ecological appreciation-grain yield increase type (type Ⅰ), ecological impairment-grain yield reduction type (type Ⅱ), ecological appreciation-grain yield reduction type (type Ⅲ) and ecological impairment-grain yield increase type (type Ⅳ). The area proportion of type Ⅰ-Ⅳ in major grain-producing areas was 18.30%, 13.36%, 33.19% and 35.05%, respectively, at the provincial level and resulted in a total of 4.171×10¹⁰ yuan of ecosystem service value loss and 9.253×10⁶ t of grain production. The arable land occupied by construction land and the arable land supplemented by unused land were the most harmful and most beneficial types of arable land use change, respectively. Therefore, it was suggested to strictly control the “non-agricultural” and “non-grain” of arable land, strengthen the ecological improvement of unused land, and actively develop complex economic agriculture such as under-forest economy and grassland economy.

Key words: cultivated land use change, food security, ecosystem service value, major grain-producing areas