The second floor is right. You should make a decision as soon as possible, and then contact the tutor immediately to see if he still has a quota.

As for the comparison between the two schools, my opinion is (for reference only):

(1) School influence: Huazhong University of Science and Technology is better than Xiamen University.

(2) Environment major: Xiamen University is famous for its marine environment major. In contrast, Huazhong University of Science and Technology does not seem to be good at environmental major, and few people are recruited.

(3) Geographical location: Xiamen is a coastal city with good development prospects and pleasant climate, which is more suitable for southerners. Wuhan is located in the land of land and water transportation hub, with developed transportation and a long history, but it seems to be inferior to Xiamen in development speed and climate.

(4) Research direction: Xiamen University's environmental science major focuses on the ocean, but little is known about Huazhong University of Science and Technology.

I believe you can make a choice that suits you. Good luck:)