Assessing landscape eco-risk associated with hilly construction land exploitation in the southwest of China: Trade-off and adaptation

Choosing a suitable low-risk location by multi-criteria methods is commonly accepted in landscape planning. However, the low risk place demonstrated on spatial patterns may not completely satisfy the urbanization requirement. In this article, we consider that except for avoiding the risks by site selection on the map, risk adaptation methods should be adopted at landscape scale. Eight ecological risk indicators were defined under the hilly construction land exploitation policy in the southwest of China. Spearman's rank correlation was then used to ascertain if there were contradictions between hilly construction land exploitation induced ecological risk and present construction land distribution. The results showed a strong positive relevance between construction land and farmland occupancy risk at all such three scales as grid, watershed, and town, which meant a low farmland occupancy risk region may not be suitable for human dwellings. Three basic farmland adjustment scenarios were put forward as the risk adaptation to reduce human construction induced ecological risk instead of changing the building site. It was found that the function adjustment scenario, which focuses on landscape connectivity, was acceptable; and the integrated adjustment scenario, which focuses on the total ecological risk and landscape connectivity, was the most advisable. The structure adjustment scenario, which only focuses on the ecological risk for construction, was less fitted. In this way, it is suggested that besides risk avoidance measures, a reasonable integration of risk adaptation approaches is required in landscape ecological risk assessment. Both concepts of risk avoidance and adaptation should be combined and emphasized in landscape planning and management.