As I see it, this is unlikely to happen. I'm not an expert in international law, but I do believe that countries have a right under international law to declare a 200-mile limit around their coastline. All that Canada is doing, in my estimation, is exercising its rights. I do not see this as potentially causing a dispute.
No one economic activity will be directly affected by this decision. It merely sets some parameters in the event that development and shipping increase in the future. This way, the regulatory framework will be in place to ensure compliance with our laws.