Waterbody loss due to urban expansion of large Chinese cities in last three decades

Abstract

Urban waterbodies are one of the most pertinent issues involved in multiple aspects of Sustainable Development Goals (SDGs). However, waterbodies in large Chinese cities are highly vulnerable to urban-land expansion, which is mostly due to economic development, population growth, and rural–urban migration. In this work, we selected 159 Chinese cities of over one million in population to investigate the encroachment on waterbodies due to rapid urbanization from 1990 to 2018. Overall, 20.6% of natural waterbody area was lost during this period to urban expansion, and this fraction varied from city to city which was related to waterbody abundance. With the acceleration of urbanization, waterbody occupation is becoming more serious (P < 0.01). However, in all cities, this encroachment has eased since 2010, which justifies the effective implementation of national-scale policies to conserve urban waterbodies. Meanwhile, gains have occurred during urbanization, in addition to the loss of waterbodies. Especially, cities lacking waterbody placed a greater emphasis on ecological factors, whose urban waterbody areas showed an increasing trend. In the future, ecological resources, including waterbody, should be considered in urban planning to provide reasonable protection to waterbodies in the quest for urban sustainability.

Measuring Urban Expansion and Land Use/Land Cover Changes Using Remote Sensing and Landscape Metrics: A Case of Rewari City, India

“…As urban areas expand and encroach upon the surrounding suburban and rural territories, essential land use categories like agricultural lands, forests, and shrubs are diminishing. Several studies worldwide have reported that urban expansion is happening at the cost of agricultural lands (Seto et al, 2011;Shi et al, 2016;d'Amour et al, 2016), grasslands (Gibson et al, 2015;Kantakumar et al, 2016), forests (Van Vliet, 2019;Lacerda et al, 2021), as well as water bodies (Xiao et al, 2022;Marufuzzaman et al, 2019).…”