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Wood-decaying fungi are essential components of degradation systems in forest ecosystems. However, their species diversity and ecological features are largely unknown. Three methods are commonly used to investigate fungal diversity: fruiting body collection, culturing, and environmental DNA analysis. Because no single method fully characterises fungal diversity, complementary approaches using two or more methods are required. However, few studies have compared the different methods and determined the best way to characterise fungal diversity. To this end, we investigated wood-decomposing Dacrymycetes (Agaricomycotina, Basidiomycota) using a complementary approach combining fruiting body collection, culturing, and environmental DNA analysis, thereby offering an effective approach for investigating the diversity of saprotrophic mushrooms. Fruiting body collection, culturing, and environmental DNA analysis detected 11, 10, and 16 operational taxonomic units (OTUs; 25 OTUs in total) and identified three, seven, and seven novel lineages, respectively. The three methods were complementary to each other to detect greater Dacrymycetes diversity. The culturing and environmental DNA analysis identified three early-diverging lineages that were not identified in the fruiting body collection suggesting that diverse lineages lacking observable fruiting bodies remain undiscovered. Such lineages may be important to understand Dacrymycetes evolution. To detect early branches of Dacrymycetes more efficiently, we recommend a combined approach consisting of a primary environmental DNA survey to detect novel lineages and a secondary culture survey to isolate their living mycelia. This approach would be helpful for identifying otherwise-undetectable lineages, and could thus uncover missing links that are important for understanding the evolution of mushroom-forming fungi.

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The structural behavior of RC beams subjected to non-uniform steel bar corrosion is studied here by developing a simplified numerical approach. At first, a modeling methodology for the steel bar corrosion is presented. Then, 3D nonlinear finite element analysis is carried out to assess the residual structural performance of RC beams with non-uniform steel bar corrosion. Obtained results from the numerical study were verified with the experimental work. Six reinforced concrete beams with identical dimensions and reinforcement layout were tested under static loading. Out of the six beams, five beams were subjected to a different level of corrosion using an electrochemical method, and another beam was used as a control specimen without corrosion. Results from the experimental and numerical study demonstrated that nonuniform corrosion of steel bars led to a significant decrease in the load carrying capacity and ductility of the RC beams. Findings of this study will be useful in assessing the residual structural performance of the RC structures with non-uniform steel bar corrosion.