Abstract:Rubber trees (Hevea brasiliensis) are widespread in the tropics and are a major source of natural rubber for strategic materials. The study of their phenology is of great importance for the production management of rubber plantations and for assessing the response of tropical vegetation to global climate change. The early phenological research mainly served the production application, such as seedling breeding, rubber tapping planning, and stress-resistant cultivation. The use of remote sensing to monitor vegetation phenology has become increasingly mature and has been widely applied to rubber trees, becoming the mainstream method for phenological monitoring. Rubber tree phenology has obvious spatio-temporal heterogeneity and its response to climate change is complex, which temperature and precipitation are key influencing factors, and both internal factors (strain, gene, and tree age, etc.) and external factors (planting density, geographic location, and agricultural practices, etc.) also affect its phenology. In order to better serve the sustainable development of natural rubber industry and scientific research on climate change in tropics, future research on rubber tree phenology should focus on the collaborative reconstruction of multi-source remote sensing data, universalization of phenological index extraction algorithms, and precision of remote sensing prediction models. The monitoring methods, service values, spatio-temporal patterns of rubber tree phenology were systematic reviewed, and put forward the existing problems and future research directions.
