In a digital world and with equipment that makes it relatively easy to produce colour images, the question asked many times is why shoot black and white? The answer is rather contradictory because you are better to shoot in colour to produce black and white images. Why would we want to do that? By shooting in colour we preserve the RGB colour channels which can be used to alter the look of the image when converting, much like using filters at the taking stage.
When taking pictures in a studio with lighting setups, you have total control. The landscape photographer does not have any control over light other than to pick a suitable day and time that will produce the type of light for dramatic monochrome images. Judging what day is suitable is difficult, unsettled days with partially broken clouds are good and can create broken dabbled light on the land that breaks up tones. Time of day is also important, early morning or late afternoon adds form and shape, also creating texture.
Photoshop can create different filter effects but it is always best to ...