The Influence of Sunshine Duration Per Day on the Important Edible Plants in Chiangmai-Lamphum Basin Area

Abstract

This research is a quantitative study with the following objectives: (1) to analyze and predict daily sunlight duration, and (2) to study the impact of daily sunlight duration on major food crops in the Chiang Mai-Lamphun basin. It uses daily average sunlight duration data from 1987 to 2022 obtained from the Northern Meteorological Center, along with future sunlight duration predictions using the Mann-Kendall Test and Sen's Slope Estimates.

The results show that the daily average sunlight duration ranges from 3.81 to 8.87 hours per day. Future sunlight duration predictions indicate a decreasing trend in January, February, April, June, and September, while other months show an increasing trend. Comparing these trends with the daily sunlight requirements of various crops reveals that sugarcane, Chinese cabbage, kale, onions, and shallots do not receive sufficient sunlight. In contrast, longan, cabbage, and scallions receive adequate sunlight only from January to April. Mangoes do not receive sufficient sunlight from June to November, similar to sweet corn and cassava, which lack sufficient sunlight in July and August. However, rice (main crop), tea, potatoes, and off-season rice receive adequate sunlight throughout their growing and harvesting periods. Considering the predicted future sunlight duration, the changing trends indicate sufficient sunlight for the entire growing and harvesting period for main crop rice, sweet corn, cassava, tea, potatoes, and off-season rice. The current and predicted situations illustrate the influence of sunlight on the growth of certain crops, with some experiencing more severe shortages in the future. Therefore, measures such as using technology to increase daily sunlight duration or adjusting planting and harvesting schedules to align with the sunlight conditions required by each type of food crop are necessary.