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Freshwater resources are vital for human and natural systems. However, anthropogenic activities, such as agricultural practices, have led to the degradation of the quality of these limited resources through pollutant loading. Agricultural Best Management Practices (BMPs), such as wetlands, are recommended as a valuable solution for pollutant removal. However, evaluation of their long-term impacts is difficult and requires modeling since performing in-situ monitoring is expensive and not feasible at the watershed scale. In this study, the impact of natural wetland implementation on total phosphorus reduction was evaluated both at the subwatershed and watershed levels. The study area is the Saginaw River Watershed, which is largest watershed in Michigan. The phosphorus reduction performances of four different wetland sizes (2, 4, 6, and 8 ha) were evaluated within this study area by implementing one wetland at a time in areas identified to have the highest potential for wetland restoration. The subwatershed level phosphorus loads were obtained from a calibrated Soil and Water Assessment Tool (SWAT) model. These loads were then incorporated into a wetland model (System for Urban Stormwater Treatment and Analysis IntegratioN-SUSTAIN) to evaluate phosphorus reduction at the subwatershed level and then the SWAT model was again used to route phosphorus transport to the watershed outlet. Statistical analyses were performed to evaluate the spatial impact of wetland size and placement on phosphorus reduction. Overall, the performance of 2 ha wetlands in total phosphorus reduction was significantly lower than the larger sizes at both the subwatershed and watershed levels. Regarding wetland implementation sites, wetlands located in headwaters and downstream had significantly higher phosphorus reduction than the ones located in the middle of the watershed. More specifically, wetlands implemented at distances ranging from 200 to 250 km and 50-100 km from the outlet had the highest impact on phosphorus reduction at the subwatershed and watershed levels, respectively. A multi criteria decision making (MCDM) method named VIKOR was successfully executed to identify the most suitable wetland size and location for each subwatershed considering the phosphorus reduction and economic cost associated with wetland implementation. The methods introduced in this study can be easily applied to other watersheds for selection and placement of wetlands while considering environmental benefits and economic costs.

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Purpose – This paper aims to empirically explore the effects of intellectual capital (IC) on supplier selection (SS) and, consequently, investigates the consecutive impacts on an Asian automotive supply chain performance (SCP). Design/methodology/approach – A questionnaire-oriented survey obtained from top managers and expert employees from three different Asian automotive industries, all of which exist in the same supply chain, was utilized for factor analysis and structural equation modeling (SEM). Findings – The findings indicate that some dimensions of IC containing human capital, relational capital and structural capital sufficiently influence evaluation and selection of optimal suppliers which lead to more efficient performance of the supply chain. Research limitations/implications – First, as the research analyzes the findings extracted from three important Asian automotive companies which exist in the same supply chain, the results may not be applicable to other industries in different countries. Second, gathering data from other elements of the supply chain like wholesalers and retailers could enrich the research conducted. Besides, more advanced statistical methods could be utilized to evaluate the regression equations and SEM. Practical implications – With a comprehensive view on IC that takes into account its creation, protection and utilization, IC plays an essential role in selecting and assessing optimal suppliers which enhance competitive advantage, especially in knowledge-based organizations. IC will also increase the SCP efficiently and effectively. Originality/value – This study develops an integrated knowledge model for a SS issue based on IC, and focuses on the effects of its various elements. It offers assistance to managers who tend to select optimal suppliers effectively.