Position rack in upper third of oven. Heat oven to 425 degrees F. Lightly oil shallow 12 x 8 x 2-inch casserole.
Bring large pot of lightly salted water to boiling over high heat. Add asparagus. Cover; after water returns to boiling, cook for 4 minutes. Scoop out with slotted spoon; rinse under cold water to stop cooking.
Add rice to boiling water. Return to boil, stirring; boil, uncovered, 10 minutes. Drain. Return rice to pot. Add dill, lemon juice, butter and salt. Turn into prepared casserole.
Place salmon, skin side down, on cutting board. Remove any bones with tweezers. Starting at wide end, slice crosswise at angle into 1/4-inch-thick slices, without cutting through skin. Place slices over rice. Discard skin. Scatter asparagus over salmon.
Melt butter in saucepan over medium heat. Stir in flour; cook 1 minute. Whisk in broth and wine; stir over medium heat until thickened and simmering, about 5 minutes. Stir in salt, pepper and nutmeg. Remove from heat. Stir in lemon juice.
Beat cream in small bowl until medium-stiff peaks form. Fold into sauce along with 4 tablespoons of Parmesan.
Pour cream sauce over casserole. Sprinkle with Parmesan.
Bake in top third of 425 degree F oven 20 minutes or until golden. Let stand 15 minutes before serving. Makes 8 servings.