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Research about diversity in Construction and Civil Engineering (CCE) has been conducted from both the academic and industrial points of view. Researchers have suggested several strategies to further attract women and ethnic minorities (WEMs) to CCE at both academic and industry levels, mainly due to the skilled labor shortage, as well as to preserve the future success of the U.S. economy. Accordingly, this literature review aims to present the current levels of diversity and inclusion of minorities in CCE at academic and industry levels, while it identifies effective strategies for increasing diversity, recognizes knowledge gaps, and suggests recommendations for future research. The review is conducted by searching relevant papers from leading construction management and engineering education peer-reviewed publications. The findings indicate that although the low participation of minorities in CCE industries and education has been studied a few times from a gender point of view, it has not received adequate attention from the ethnicity perspective, especially at the academic level. This paper contributes to the body of knowledge by bringing together information related to the underrepresentation of WEMs in CCE academia and workforce environments and identifying the potential reasons for this low participation. 

The heavy reliance on compost inputs in urban gardening provides opportunities to recycle nutrients from the urban waste stream, but also creates potential for buildup and loss of soil phosphorus (P). We previously documented P in leachate from raised-bed garden plots in which compost had been applied, but the fate of this P is not known. Here, we measured P concentrations in soils below four or six-year-old urban garden plots that were established for research. We hypothesize that the soil P concentration and depth of P penetration will increase over time after gardens are established. Soil cores were collected in five garden plots of each age and quantified for inorganic weakly exchangeable P. Inorganic weakly exchangeable P was significantly elevated in native soil below garden plots (>35 cm deep) relative to reference soil profiles, and excess P decreased with increasing depth, although differences between garden plots of different ages were not significant. Our analysis shows that excess P from compost accumulates in native soil below urban garden plots. While urban agriculture has the potential to recycle P in urban ecosystems, over-application of compost has the potential to contribute to soil and water pollution. 

Cities are increasingly making decisions related to sustainability, and information from the field of urban ecology may be useful in informing these decisions. However, the potential utility of this information may not translate into it actually being used. We surveyed municipal sustainability staff through the Minnesota GreenStep Cities program documenting their information needs and information sources, and used these results to identify the frequency with which urban ecologists are publishing studies of potential relevance to practitioners. We also quantified funded awards from the U.S. National Science Foundation in urban ecology that explicitly describe active partnerships with city policy makers. Our results show that urban ecologists are increasingly generating information of potential relevance to city sustainability efforts, with rapid increases in the number of articles published and grants funded on areas identified as key information needs. Our results also suggest that the transmission of information from academic urban ecologists to practitioners occurs mostly through indirect pathways, as municipal sustainability staff reported relying heavily on general web searches and government agency websites to find information. We found evidence of an increasing frequency of active collaborations between urban ecologists and policy makers from NSF grant abstracts. Our findings are consistent with previous findings that traditional models of passive communication to practitioners through academic journals results in a low efficiency of use of this knowledge, but that the potential for urban ecologists to help inform municipal sustainability initiatives through active collaborations with practitioners is great. 

The composition of bioretention soil media (BSM) is among the most critical design attributes contributing to the water quality performance of bioretention systems, as various amendments may increase the capacity for chemical sorption of certain nutrient pollutants. We investigated the spent lime (a calcium-based water treatment residual) as BSM amendments for nutrient retention. The study was conducted in two parts: the first was a field-based mesocosm experiment in which we assessed the effect of spent lime amendments on leachate nutrient concentration for treatments receiving different levels of phosphorus and nitrogen loading (simulated by different levels of compost added to the substrate). The second was a laboratory study comparing various levels of spent lime and coir on leachate nutrient concentration at two different simulated loading rates. Effluent water was collected and analyzed for PO43−, NH4+ and NO3− concentrations in the field and lab. Spent lime significantly reduced leachate PO43− concentrations (upwards of 50%) in both the field and lab mesocosm studies compared to treatments without spent lime. Reductions in NH4+ concentrations were also observed due to spent lime but with variable significance across the different compost levels, whereas NO3− concentrations were higher in plots with spent lime than plots without spent lime. In the lab, columns with coir had significantly higher leachate PO43− concentrations compared to spent lime-treated columns, however, leachate NH4+ and NO3− concentrations did not significantly differ between treatments at the same compost levels. This study shows that spent lime, which is a waste product, is effective in significantly reducing leachate PO43− concentrations from BSM, while be a cost-effective substitute to engineered proprietary media that is expensive to acquire; however, future studies must also evaluate its potential for clogging.