关键词: 气候变化, 荔枝, MaxEnt模型, 环境变量, 地理分布

Abstract:

Based on global litchi distribution records and environmental variables from different climate scenarios during the base period (1970−2000) and future periods (2050s and 2090s), this study utilized the optimized MaxEnt maximum entropy model to analyze the key environmental variables influencing litchi distribution and predict its potential geographic distribution. The aim was to provide a theoretical basis for the sustainable development of the litchi industry by predicting the impact of climate change on the global distribution pattern of litchi. The results indicated the following: (1) the most important environmental variable affecting litchi distribution was the mean temperature of the coldest quarter (bio11), followed by precipitation of warmest quarter (bio18) and precipitation of wettest quarter (bio16). The values of bio11, bio18, and bio16 at a distribution probability of Q ≥ 50% ranged from 11−22°C, 487−1875mm and 554−2052mm, respectively. (2) Compared to the base period, the main areas of change in litchi’s potential distribution were in China and India. The highly and moderately suitable areas for litchi in different periods were primarily located in the southern regions of China, followed by India and Vietnam, with southern China having the largest highly suitable zone in the world. (3) In the future period, the suitable areas in southern China were projected to expand to higher latitudes. In particular, under the SSP5−8.5 scenario for the 2090s (2081−2100), the high, moderate and slight suitable areas would shift northward by 2° 4° and 6°, respectively, while the suitable area in India will expand westward by 15°. (4) Under the SSP2−4.5 scenario, the total suitable area was expected to increase significantly, especially in the slightly suitable zones. In contrast, under the SSP5−8.5 scenario, both moderate and slight suitable areas were predicted to decrease, with the slightly suitable area reaching its smallest size in the 2090s. However, the area of highly suitable land was projected to peak at 154.6×10⁴ km². (5) The distribution center of litchi was expected to shift toward higher latitudes, with the largest offset and the widest latitude span occurring under SSP5−8.5 in the 2090s. A comprehensive analysis suggests that global warming will lead to the northward expansion of suitable areas for litchi cultivation. However, the increasing frequency of extreme weather events poses significant challenges. The selection and breeding of litchi varieties with broad climatic suitability and high resistance are crucial for the sustainable development of the industry.

Key words: Climate change, Litchi chinensis, MaxEnt, Environmental variables, Geographical distribution