I graduated in environmental science and went on to study environmental management. I became chartered as a water and environmental manager, got an MBA and had a few interesting roles. But I would not do it again. The employment market has really dried up in environmental sectors. A few years ago there were only a few universities that had a decent spread or research schools and field centres and you would get interviews and job offers everywhere. But now there must be 20 times as many courses and 50 times as many graduates, many of whom will compete by getting a PhD. I cannot recommend doing something you love on the hope it will pay your bills. Do something that people are willing to pay money for. Then use that money to do what you want in life. Some specialisms will barely pay your bills, others will save you enough money to take numerous degrees, get a mortgage, start a business and travel the world. It's dumb logic to assume that career progression follows every discipline. There will always be somebody from a wealthier background who is buying every course going and has all the right family connections to give them a massive advantage if you pick an employment market that is saturated.
A good way to find out is to take free MOOC courses and see whether you actually enjoy the subjects. I did the Open University: effect of pollutants on the aquatic environment and the understanding water quality courses last year. I also tried out a few industry courses in: quality management, health and safety, nuclear environmental reporting, carbon footprinting, environmental legislation, energy management, and information security management... just to name a few . All in the last year. I would not dream of starting a three-year degree without trying at least 4 or 5 different courses beforehand. And I would also register as a student or affiliate in the closest professional body to network with people actually doing these roles.
This is what everyone gets wrong. They rush out the door to escape their parents on the hope of having a fantastic time, only to find that they are up against people with 20 years industry experience and a doctorate, they end up waiting endlessly for a job, only to find that nobody cares what they think and that most roles are actually very unstimulating. Environmental Impact Assessment is a prime example, sounds great, but is totally boring because you have to word-match every report, that nobody wants anyway, and it's like following a script. I know an ecologist who is told exactly how many photographs to take, what lens angle, and the precise information that had to be filled in. For Network Rail we were filling in a spreadsheet and ticking boxes to ensure that the assessments were confined, and that was working for a Fortune 100 civil engineering company. They didn't even want site walkovers. The data was so confidential that you didn't even know who the project manager was or what they were building. If your role does not add any value and you end up getting bored mindless, then you can have the most interesting subject in the world, but you'll never do anything except read about the subject and recite rhetoric.
If I was you I would come up with a list of actual jobs, and then work backwards to the degree choice. Then try to pick one that is readily available. If you want a shop, then the place to start is by reading some proper MBA textbooks and finding a niche or formulating a strategy for what you are going to do to compete. The people that work at my local fish shop have at least two degrees in fish biology or marine science. When you chat to them, you find out how hard they have worked to get a job that pays little more than most shop workers get. It's sad, but it's true. And there is an endless list of people trying to get the roles or who have the cash to start a business tomorrow. What would a business degree actually teach you. If you can see value in becoming a ichthyologist or a hydroponics expert then go ahead. But the value lies in finding something somebody actually wants. If they need a store manager, then yes a business degree would help, but they are going to need leadership and management skills, order processing skills, financial planning skills, marketing skills and a wide variety of training and experience that you need to develop alongside doing a bachelors degree. Do you want to run an aquatic shop or work in a zoo? Will you be the owner? The manager? The advisor? That is the way to look at it. Contact the big companies and ask to volunteer. Find out what people actually do in the industry. Then come back and choose your university route.