Uncertainty analysis for an effluent trading system in a typical nonpoint-sources-polluted watershed

Abstract

Conventional effluent trading systems (ETSs) between point sources (PSs) and nonpoint sources (NPSs) are often unreliable because of the uncertain characteristics of NPSs. In this study, a new framework was established for PS-NPS ETSs, and a comprehensive analysis was conducted by quantifying the impacts of the uncertainties associated with the water assimilative capacity (WAC), NPS emissions, and measurement effectiveness. On the basis of these results, the uncertain characteristics of NPSs would result in a less cost-effective PS-NPS ETS during most hydrological periods, and there exists a clear transition occurs from the WAC constraint to the water quality constraint if these stochastic factors are considered. Specifically, the emission uncertainty had a greater impact on PSs, but an increase in the emission or abatement uncertainty caused the abatement efforts to shift from NPSs toward PSs. Moreover, the error transitivity from the WAC to conventional ETS approaches is more obvious than that to the WEFZ-based ETS. When NPSs emissions are relatively high, structural BMPs should be considered for trading, and vice versa. These results are critical to understand the impacts of uncertainty on the functionality of PS-NPS ETSs and to provide a trade-off between the confidence level and abatement efforts.

An Improved Calibration and Uncertainty Analysis Approach Using a Multicriteria Sequential Algorithm for Hydrological Modeling

“…For hydrological studies, parameter uncertainty has always been given the most concerns. According to empirical estimations, the uncertainty of model parameters may compromise the reliability and precision of modeling results, such as physical significance, generalized inference, and observed data 21,22 . Moreover, the interactions between the parameters also cause uncertainties.…”

Understanding the behavior of an effluent generation indicator throughout uncertainty analysis

“…Unfortunately, the task of including uncertainties related to environmental performance indicators still remains an open issue. In fact, evaluating the impact of modeling uncertainties concerning to performance indicators seems to be in a mature stage, since the seminal work of Bertrand-Krajewski et al (2002), whose efforts are associated with the design and the operation of urban drainage systems, until recent developments, for instance, Chen et al (2016), which focuses on the evaluating of impacts of the uncertainties associated with the water assimilative capacity in conventional effluent trading system, and Azadeh et al (2017), which deals with a multi-objective mathematical model for integrating upstream and midstream segments of crude oil supply chain in the context of environmental indicators. Nonetheless, the explicit inclusion of measurement uncertainties following the internationally recognized framework, Guide to the Expression of Uncertainty in Measurement-GUM (BIPM et al 2008a) and its Supplement 1-GUM S1 (BIPM et al 2008b), is still incipient in this area of knowledge.…”