Roasted Salmon with Celery and Bulgur Salad

Name: Roasted Salmon with Celery and Bulgur Salad
Ingredients: ½ cup walnuts; 1 1½-pound piece skin-on salmon fillet; Kosher salt; ½ cup coarse whole grain bulgur (not quick-cooking); 2 bunches small white turnips (about 1½ pounds total), trimmed; 4 tablespoons olive oil, divided; plus more for drizzling (optional); ¼ cup plain Greek yogurt; 1 tablespoon white wine vinegar; 2 tablespoons fresh lemon juice, plus more for drizzling; 4 celery heart stalks, plus leaves for serving; ¼ preserved lemon, flesh removed, rind finely chopped; ¼ cup finely chopped golden raisins; ¼ cup parsley leaves with tender stems