I suggest that if you contribute, save it in JPG format in RGB mode (the resolution should not be too high) and send it to the publishing house. When they are sure they can use it, they will inform you that the pictures are ready to be published, and will tell you the detailed resolution and size, and then save them as TIFF format in CMYK mode. This is the basic knowledge of copyright protection. If you send them a picture of publishing quality, and they say they don't use it, but use it privately elsewhere (such as what illustrations or basemaps are printed), then things will be unhappy. At present, China's social integrity and the rule of law are very weak, so why take risks on your own?

According to the requirements of the publishing house, the final format of the pictures needed for printing is CMYK, and the general publishing society explicitly requires the contributors to provide the format and size of the pictures. However, it doesn't matter if it's just a submission. The editor will read it before deciding whether to use your painting. If he decides to use it, he will definitely communicate with you further and tell you their requirements in detail.