Qinghai-Tibet region is an alpine pastoral area. What about the northwest?

The Qinghai-Tibet region is mostly a cold pastoral area, and Mongolian yurts are traditional houses in the northwest, so A is wrong;

The northern region is dominated by dry land, and the diaojiao building is a traditional residence in the southern region, so B is wrong;

The prominent feature of the natural environment in northwest China is drought, and Tangji agriculture is the agricultural feature of the Pearl River Delta region, so C is wrong;

There are many rivers in the south, and ships are commonly used means of transportation, so D is correct.

Therefore, choose: d.