Fill a large pot with water, then bring to boil. Peel turnips and chop into bite-sized pieces. Add turnip bits to water, cover and reduce heat to low. Simmer until turnips are tender, about 25 minutes. Drain and set aside.
In a large stock pot, heat the oil over medium-high heat. Chop onion, carrot, celery and peppers. Add to oil, along with turnips. Toss well. Add paprika, cumin, cinnamon, aleppo pepper and saffron. Stir in greens.
Add diced tomatoes plus any juice from the can. Stir well. Bring to boil, then cover and reduce heat to low. Let it simmer on its own for 45 minutes or so, until vegetables are tender.
Add preserved lemon, chopped fine, or the juice of 1 fresh lemon. Add sea salt to taste.
Just before serving, stir in finely chopped parsley and cilantro.
Serve over whole grain couscous.