*4.3. Adjustment of USWS*

Figure 6 presents the values of solid waste production intensity (SPI) under 32 scenarios, showing the value of SPI was volatile. The SPI approached 0.487 (under S32) in 2012 and reached 0.228 (under S32) in 2017. The SPI decreased by 1.43% (under S4) to

18.89% (under S1) in 2012, and the SPI declined by 3.51% (under S6) to 17.98% (under S1) in 2017. Under S1, the strictest direct solid waste reduction policy was implemented in all sectors, while the sectoral direct consumption coefficients were maintained at high levels. Under S4 and S6, the loose direct solid waste reduction policy was implemented to PM, while the sectoral direct consumption coefficients of PM and AM were maintained at high levels. This implies that conducting strict environmental policy on AM and PM, as well as reducing the commodity consumption of CON, TRA, and OTH from other sectors (e.g., improve material usage efficiency and develop advanced material) would be useful for reducing SPI of the USWS.

**Figure 6.** The values of solid waste production intensity (SPI) under 32 scenarios: (**a**) 2012; (**b**) 2017. ("S" means "Scenario).

Figures 7–9 describe results of sectoral solid waste production and ecological network analysis under six scenarios in 2012 and 2017. Corresponding SPI values were lower than the actual values. In Figure 7, results showed that the amounts of solid waste production decreased by 3.82% (under S27) to 17.95% (under S1) in 2012 and decreased by 3.39% (under S27) to 16.30% (under S1) in 2017. The reduction of AM solid waste production was the highest among all sectors. In 2012, the amount decreased 34.438 <sup>×</sup> <sup>10</sup><sup>6</sup> t (under S27) to 49.834 <sup>×</sup> <sup>10</sup><sup>6</sup> t (under S1); in 2017, the amount reduced 1.511 <sup>×</sup> <sup>10</sup><sup>6</sup> t (under S27) to 13.885 <sup>×</sup> <sup>10</sup><sup>6</sup> t (under S1). These results reveal that the selected scenarios can effectively reduce solid waste production. In Figure 8, results indicate that the total weights of all sectors changed with the varied scenarios, implying that the system hierarchy structure was sensitive to the variations in factors. In 2012, the total weight of PM and AM were in the range of 61.47% (under S1) and 63.71% (under S4), an increase of −0.87% to 1.37% compared with that under S32. In 2017, the total weight of PM and AM was in the range of 53.53% (under S1) and 54.24% (under S6), a decrease by 0.75% to 1.46% compared with that under S32. According to former descriptions in status analysis, it was desired that the total weight of PM and AM should decrease. These results indicate that the selected designed scenarios could help adjust the hierarchical structure of USWS. In Figure 9, results show that the number of mutualistic, competitive, and exploitation relationships had no obvious changes; other measurements needed to be detected.

**Figure 7.** Sectoral urban solid waste production under different scenarios.

**Figure 8.** Sectoral total weight under different scenarios.

**Figure 9.** Pairwise sectoral relationships under different scenarios. (**a1**) 2012\_S1; (**a2**) 2012\_S6; (**a3**) 2012\_S7; (**a4**) 2012\_S26; (**a5**) 2012\_S27; (**a6**) 2012\_S29; (**b1**) 2017\_S1; (**b2**) 2017\_S6; (**b3**) 2017\_S7; (**b4**) 2017\_S26; (**b5**) 2017\_S27; (**b6**) 2017\_S29.
