. 2021 Aug 19;29(3):4654–4667. doi: 10.1007/s11356-021-15161-1

Table 2.

Standards for identifying the coupling coordination between urbanization and water environment

Primary division	Coupling coordination (D)	Secondary division	Comparison between f(x) and g(y)	Tertiary division
Balanced development (acceptable interval)	0.85<D≦1	Superiorly balanced development	f(x) > g(y) f(x) = g(y) f(x) < g(y)	Superiorly balanced development with environment lagging behind Superiorly balanced development of urbanization and environment Superiorly balanced development with urbanization lagging behind
Balanced development (acceptable interval)	0.7<D≦0.85	Coordinated development	f(x) > g(y) f(x) = g(y) f(x) < g(y)
Transitional development (transitional interval)	0.5<D≦0.7	Barely coordinated development	f(x) > g(y) f(x) = g(y) f(x) < g(y)	Superiorly balanced development with environment lagging behind Superiorly balanced development of urbanization and environment Superiorly balanced development with urbanization lagging behind
Imbalanced development (unacceptable interval)	0.25<D≦0.5 0<D≦0.25	Slightly imbalanced development Severely imbalanced development	f(x) > g(y) f(x) = g(y) f(x) < g(y)	Superiorly balanced development with environment lagging behind
				Superiorly balanced development of urbanization and environment
				Superiorly balanced development with urbanization lagging behind