Complex sentence: By 2020, the Ontario tobacco belt will become the "Ontario horticultural centre" because of its abundance of water, proximity to urban markets (e.g., Hamilton, Kitchener, London), and a sandy soil that favors horticulutural crops.
Split into simpler sentences: By 2020, the Ontario tobacco belt will become the "Ontario horticultural centre" because of its abundance of water. Other reasons for the sudden transformation of this region include proximity to urban markets (e.g., Hamilton, Kitchener, London) and a sandy soil that favors horticulutural crops.