Impacts of urbanization at city cluster scale on ecosystem services along an urban-rural gradient: a case study of Central Yunnan City Cluster, China.

Urban agglomeration will be the main mode of future urbanization in China, greatly influencing social and economic development and ecosystem protection at the whole city cluster scale. It is important to analyze the impacts of large-scale, scattered land use and cover change (LUCC) consisting of one-pole-multi-point urbanization in city clusters on regional ecosystem services (ESs), so as to increase ecological security and maintain ES levels. Using the urban-rural gradient analysis method (UGAM), this study examined driver-response mechanisms of large-scale, scattered agglomeration urbanization on ESs along an urban-rural gradient and at a regional scale. This was done by simulating and analyzing tempo-spatial variations in ES characteristics along concentric ring gradients in the Central Yunnan City Cluster (CYCC) under its present urbanization path. The results showed that rapid urban sprawl is the main driver affecting the integral value of ESs in CYCC and that ES trade-offs (through LUCC caused by urbanization) between adjacent zones along the urban-rural gradient will particularly exacerbate the degradation of integral ES levels. Hence, CYCC should follow a sustainable, eco-friendly urbanization path and consider ecological principles and the impact of LUCC on regional ESs along the urban-rural gradient in top-level design and decision-making on urban planning and strategic land use management. Differentiated regional development policies should be formulated for each area, the urban-rural development pattern and layout optimized, the scale of construction land rationally controlled, and the overall efficiency of land use improved. Ecological buffers should be set up around areas with sharp and obvious changes in land use, to alleviate the negative impact of large-scale, decentralized city cluster urbanization on regional ESs.

Scale effects on the relationships between land characteristics and ecosystem services- a case study in Taihu Lake Basin, China.

It is generally recognized that marginal changes in landscape characteristics can influence multiple ecosystem services, but the causal relationships involved are still very unclear due to lack of knowledge and data gaps. Planners and managers need spatial information and evidence on these causal relationships for systematic and sound land planning. This study evaluated the effects of landscape characteristics on seven types of ecosystem services and the trade-offs among the ecosystem services by combining statistical data and the InVEST model with correlation analysis across Taihu Lake Basin, China. We found that all ecosystem services except food production increased from 2005 to 2015 in the whole basin. We also found that correlations between landscape characteristic metrics and ecosystem services indicators changed over time for different types of ecosystem service indicators at the county scale, and between county and pixel scale. The results demonstrated the effects of landscape characteristic metrics on multiple ecosystem services indicators and the tradeoffs among these ecosystem services indicators, and also revealed scale effects on correlations and tradeoffs. Therefore planners and managers need to consider both landscape characteristic metrics and scale effects for effective landscape management to improve ecosystem services and reduce unwanted tradeoffs.