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The main goal in this research is study of impacts of various likelihood functions on DREAM(zs) (Differential Evolution Adaptive Metropolis) method results in simulation-optimization model of aquifer. In this study, DREAM(zs) algorithm has been developed to study aquifer simulationoptimization model uncertainties. DREAM(zs) is used to investigate uncertainty of parameters of the simulation-optimization model in Isfahan-Barkhar aquifer, Isfehan province, Iran. This study is carried out on an aquifer simulation model of MODFLOW that is coupled with MOPSO (multi-objective particle swarm optimization) optimization. Three likelihood functions, L1, L2, and L3, are considered as informal and the remaining (L4 and L5) are represented as formal categories. Likelihood function L1 is Nash-Sutcliffe efficiency and L2 is based on minimum mean square error. L3 uses estimation of model error variance and L4 focuses on the relationship between the traditional least squares fitting and the Bayesian inference. In likelihood function L5 the serial dependence of residual errors is calculated using a first-order autoregressive model of the residuals. Results suggested that the parameters sensitivity depend on the likelihood function selection, and sensitivity of all parameters is not similar in different likelihood functions. MOPSO algorithm outputs indicated that likelihood function No. 5 has a higher speed in reaching convergence and this function also showed that objective functions had a better performance compared to the other likelihood functions. [ABSTRACT FROM AUTHOR]

This paper intends to assess the seasonal demand for nitrogen discharge permits and its influence on waste load allocation (WLA) strategies. For this purpose, the Sefidrud catchment is analyzed, where the agricultural demands for discharge permits and reclaimed water (RW) are significant and also intermittent. The paper discusses using variable total maximum daily loads and a transferable discharge permit (TDP) with respect to the farming and non-farming seasons to achieve annual economic benefits. However, an integrated TDP and RW market can considerably increase these revenues. Moreover, the latter may provide the flexibility required for practical dynamic WLA and makes it compatible with seasonal demands. The optimal WLA also determines the required wastewater treatment processes. Here, some should be designed and equipped with flexible operational processes. As a result, the novel integrated management approach saves 25% and 13% in comparison with the conventional TDP market in the short and long term, respectively. This framework also recommends the pricing for permits in a year to enhance stakeholders' motivation for active participation. It is concluded that the integrated TDP and RW market, using the recommended treatment processes and dynamic pricing, is an economically attractive and practical policy for seasonal WLA. [ABSTRACT FROM AUTHOR]