Maritime imports have the following characteristics:

1.Ocean passage: Sea lanes are natural waterways, and their ability to pass through them is almost unlimited。

2.Large transport volume: large passenger ships up to 80,000 tons, large oil tankers more than 600,000 tons 。 The tonnage of general cargo ships is 50,000-60,000 tons, bulk carriers are 200,000-300,000 tons, and 5000-600 TEU containers 。

3.Low freight: The unit cost of shipping by sea is lower。It is about 1/20~25 of the railway freight, and 1/50~300 of the air freight。Low energy consumption。

4.The speed is slower: generally 10-20 knots per hour, the latest containers are 35 knots per hour。

5.Greater risk than other modes of transport: more affected by natural conditions and climate。