Explanatory variable	（SYS-GMM two step method）
Explanatory variable	Aggregate investment for industrial treatment/GDP	The investment for treating the industrial waste gas/GDP	Investment for treating the industrial waste water/GDP	Investment for treating the industrial solid wastes/GDP
The first order lag of each variable being explained	0.244^***	0.166^***	0.259^***	0.0500^***
The first order lag of each variable being explained	(0.0540)	(0.0308)	(0.0414)	(0.0185)
Degree of fiscal decentralization	−655.9^***	−441.2^***	−316.6^***	22.90
Degree of fiscal decentralization	(80.72)	(68.43)	(67.12)	(31.90)
The quadratic term of degree of fiscal decentralization	586.4^**	335.9^*	650.4^***	0.300
The quadratic term of degree of fiscal decentralization	(232.8)	(177.4)	(235.9)	(104.7)
Economic development level (taking the logarithm)	22.16^***	20.68^***	1.027	−1.600^***
Economic development level (taking the logarithm)	(5.986)	(6.217)	(2.373)	(0.522)
Industrial structure	12.41	−19.17^***	20.93^***	−2.572^*
Industrial structure	(23.01)	(5.724)	(2.343)	(1.521)
Intensity of competition between governments	−152.3^*	−207.9	−89.25	−7.818
Intensity of competition between governments	(377.0)	(343.2)	(100.3)	(34.75)
Degree of opening to the outside world	46.29^*	−23.28	5.371	3.584^**
Degree of opening to the outside world	(24.65)	(21.69)	(5.513)	(1.517)
Population density	−19.35	−10.98^***	−5.925	−3.093^***
Population density	(14.52)	(3.183)	(4.539)	(0.337)
Constant term	47.87	34.18	41.51	30.58^***
Constant term	(88.58)	(25.57)	(28.37)	(2.564)
Over-distinguished P value (Sargan test )	1	1	1	1
Second order serial correlation testing P value	0.1512	0.5532	0.3299	0.2710
Sample number	480	480	480	480