Preheat your oven to 400°F and line a baking sheet with parchment paper.
Peel and dice the carrots and turnips into uniform half-inch cubes to ensure even roasting.
Toss the diced vegetables with the ghee, half of the sea salt, half of the black pepper, and all of the garlic powder.
Spread the vegetables in a single layer on the baking sheet and roast for 15 minutes.
While the vegetables roast, finely chop the fresh dill and parsley.
In a small bowl, whisk together the Greek yogurt, Dijon mustard, lemon juice, and the chopped fresh herbs.
Pat the salmon fillet dry with a paper towel and season with the remaining sea salt and black pepper.
Spread the herb and yogurt mixture evenly over the top of the salmon fillet to create a thick crust.
Remove the baking sheet from the oven, move the vegetables to one side, and place the salmon on the other side.
Return the pan to the oven and roast for another 10 to 12 minutes until the salmon is flaky and the vegetables are golden brown.
Transfer the roasted root vegetables to a shallow bowl and place the herb-crusted salmon on top to serve.