Allocating and mapping ecosystem service demands with spatial flow from built-up areas to natural spaces.

Co-urbanized areas around large cities in developing countries face the problem of spatial disconnection between supply and demand areas of ecosystem services (ES). To explore the reflection of human needs in the nonadjacent surrounding natural spaces and identify the response of the existing natural space system to the ES demand in terms of total amount and spatial distribution, a new method for ES demand mapping in co-urbanized areas was proposed. Based on the theory of the ES delivery chain, urban built-up areas are identified as service benefiting areas (SBAs) and the sources where demands are generated, natural spaces are regarded as service provision areas (SPAs) and the sinks and destinations where demands are satisfied, and ES spatial flow is considered as the delivery mechanism and ecological process that promotes the demand flow from sources to sinks.

Backcasting approach with multi-scenario simulation for assessing effects of land use policy using GeoSOS-FLUS software.

The method presented is helpful for assessing effects of land use policy and unfolding the action mechanism and implementation effect of policies on land use changes. The backcasting method is based on the re-simulation of the historical real changes of land use. By observing the error between the real and simulated states, adjust the parameters for many times, and a variety of land use scenarios are obtained, and the scenario with the minimum and acceptable error is selected to assess the effects of land use policy represented by its parameters.