Rinse rice, and drain well. Cook rice in boiling water 35 minutes or until al dente; drain. Cool.
Heat a nonstick skillet over medium-high heat. Coat pan with cooking spray. Add salmon; cook 3 minutes on each side or until fish flakes easily when tested with a fork or until desired degree of doneness. Cool; break into bite-sized pieces.
Combine juice and next 4 ingredients (through garlic) in a large bowl, stirring well with a whisk. Gradually add oil to juice mixture, stirring constantly. Add rice, mango, tomatoes, onions, pepper, and spinach; toss gently. Place 1 cup rice mixture in each of 6 bowls; top each with 1 ounce salmon.