The temperature in tropical rain forest is 25 ~ 30℃, the average temperature in Leng Yue is above 65438 08℃, and the extreme maximum temperature is mostly below 36℃. The annual rainfall usually exceeds 2 000mm, and some even reach 6 000 mm. The annual rainfall is evenly distributed and humid all the year round, and the relative humidity of the air is above 95%. Tropical rain forest is a typical vegetation of tropical rain forest climate and tropical marine climate. Most tropical rainforests are located between 23.5 degrees north latitude and 23.5 degrees south latitude (that is, the area between the Tropic of Capricorn and the Tropic of Cancer). In tropical rain forests, there are usually three to five layers of vegetation, and trees as high as 150 feet to 180 feet are covered like tents. The density of lower vegetation depends on the degree to which sunlight penetrates the upper trees. The more sunlight, the greater the density. Tropical rainforests are mainly distributed in the jungle areas of South America, Asia and Africa, such as the Amazon Plain and Xishuangbanna, Yunnan. The monthly average temperature is above 64.5 degrees Fahrenheit (about 18 degrees Celsius), and the annual average precipitation is above 80 inches (1 inch =2.54 centimeters), which exceeds the annual evaporation. /kloc-in the 9th century, German botanist Simbel extensively collected and summarized scientific discoveries and various materials in the tropics, and named the evergreen tall forest vegetation in the humid tropics as tropical rain forest, and made a scientific description and explanation from the ecological point of view at that time. Tropical rain forest has unique appearance and structural characteristics, which is obviously different from other forest types in the world. Tropical rainforests mainly grow in tropical humid lowlands with an annual average temperature above 24℃, or the average temperature in Leng Yue is above 18℃. Most tropical rainforests are mainly distributed in four biogeographic regions: tropical region (African continent, Madagascar and some scattered islands), Australia region (Australia, New Guinea and Pacific Islands), Indonesia region (India, Sri Lanka, Asian continent and Southeast Asia) and neotropical region (South America, Central America and Caribbean Islands) [1].