Final answer:
Horizontal integration results in increased market power, reduced competition, and higher barriers to entry, typically increasing a firm's dominance in the industry.
Step-by-step explanation:
The result of horizontal integration, in terms of Porter's five forces model, primarily includes 1) Increased market power, 2) Reduced competition, 3) Higher barriers to entry, and it may also result in 4) increased bargaining power, although this is typically associated with vertical integration. By amalgamating with or acquiring competitors, a firm can increase its market share, which gives it more power over prices and the dynamics of the market. This consolidation reduces the number of competitors, making it harder for new firms to enter the market due to higher costs of entry and scaled economies that favor larger players. While suppliers might have less bargaining power due to the firm's increased size, it is essential to distinguish that improved bargaining power of suppliers is not a typical outcome of horizontal integration as it would be in vertical integration scenarios.