Preheat the oven to 375°. In a large ovenproof skillet, heat the canola oil until shimmering. Add the Jerusalem artichokes, carrots, parsnips and potatoes and cook over moderately high heat, stirring occasionally, until lightly browned, about 8 minutes. Transfer the skillet to the oven and roast for about 20 minutes, until all the vegetables are tender.
Add the sliced lotus root to the skillet along with the maple syrup and soy sauce. Cook the vegetables over moderate heat, stirring frequently, until the sauce becomes syrupy and the vegetables are glazed, about 8 minutes. Stir the sesame oil, sesame seeds and sliced scallions into the vegetables and serve immediately.