Abstract:

To study the effects of different types of summer high-temperature weather on the growth and development of river crabs, this article mainly focused on the extreme high temperatures in Xinghua during the summer of 2022 and 2024, analyzed the characteristics of high temperature, circulation causes, and specific impacts on the growth and development of river crabs, and studied the specific reasons leading to the yield reduction of river crabs. The results indicated that in 2022, due to the abnormally strong westward shift of the Western Pacific Subtropical High and the abnormally eastward extension of the South Asian High, Xinghua exhibited early occurrence, scattered distribution, strong extremism, and relatively dry characteristics of high temperature in summer. However, the high temperatures were temporarily interrupted in mid to late July, with less and stable precipitation. The overall water environment was stable, and the shedding of river crabs was relatively favorable, resulting in a relatively small loss of final yield; in 2024, influenced by the strengthening of the subtropical high and the warm high pressure of the westerly belt, the high temperature would show characteristics of late occurrence, concentrated distribution, strong extremism, and more extreme precipitation. The high temperature was concentrated in the molting period of river crabs. When the rainstorm was frequent, the water temperature and dissolved oxygen in crab ponds changed violently, so the river crabs were prone to stress reactions; at the same time, the high temperature ended lately, and the food intake in the fattening period before marketing decreased, resulting in a large loss of final yield. Defensive measures such as scientific oxygenation, water level control, water temperature regulation, and strengthening meteorological monitoring and warning can be taken to cope with high-temperature heat damage, reduce or avoid losses, and promote the increase in yield, income, and quality of river crabs.

Key words: river crab culture, meteorological disaster, high temperature causes, defensive measures, Xinghua, Jiangsu