How environmental conditions, phenological periods, and production endowment affect lychee yield

The increasingly revealed effects of climate change threaten tropical fruit production. Considerable production loss and unstable yield has been observed in China and other regions with similar climate condition. Accordingly, this paper aims to explore the impacts of environmental conditions, phenological periods, and production endowments on a tropical fruit yield, namely lychee, by using the extended Cobb-Douglas model. Lychee (Litchi chinensis Sonn.) is chosen as the focus of this study given it is one of the most climate-sensitive tropical fruits which have important contributions to the health, economy, and culture in South China. The growth-span was divided into four phenological periods, namely: exposure period, heading period, flowering period and maturing period. A two-way fixed effect model is employed for county-level mixed-frequency panel data. This data comprises lychee yield, environmental conditions (mean temperature, minimum temperature, and precipitation), production endowments (labor input, capital input, and technical input), and phenological periods in 39 main producing counties in China from 2011 to 2019. The key conclusions of interest are (1) higher minimum temperature results in larger lychee yield, (2) higher minimum temperature in the earlier phenological period has larger positive impact on lychee yield, and (3) higher growth in technical input causes lower lychee yield, and an explanation is provided. Heterogeneity analysis further implies various effects of the minimum temperature influencing lychee yield. The minimum temperature has a significant positive effect on lychee yield in non-coastal and non-western counties, especially in earlier phenological periods.