The correct answer is option 4. This statement is not correct because the world`s important deserts are not located across the equator. Deserts are typically found in regions that have low rainfall and high temperatures, which are typically found around the Tropic of Cancer and the Tropic of Capricorn. Examples of important deserts include the Sahara Desert in Africa, the Arabian Desert in the Middle East, and the Mojave Desert in North America. These deserts are located in latitudes outside of the equator. Therefore, option 4 is incorrect.

Option 1 is correct. More than 50% of the world`s animal species are found in tropical rainforests. These dense forests are home to a wide variety of species due to the abundance of resources and favorable climate conditions.

Option 2 is correct. Approximately one-third of the Earth`s land surface is arid or semi-arid, meaning it receives very little rainfall and is often dry. These regions include deserts, steppes, and certain coastal areas.

Option 3 is correct. Floating plants, also known as phytoplankton, in the ocean produce over half the world`s oxygen. These microscopic organisms use sunlight and carbon dioxide to photosynthesize and release oxygen as a byproduct