What is the meteorological disaster that has the greatest impact on China's agricultural production?

Affected by the instability of summer monsoon, drought is the most common, widely distributed and most influential meteorological disaster in China. Cold wave occurs in winter and spring, which has little influence on agricultural production. Typhoons mainly occur in China's coastal areas, and the distribution of floods is not as large as that of droughts.

The impact of drought on agriculture;

When dry weather occurs, especially winter and spring drought and summer drought will hinder the normal growth and development of crops. In winter and spring, spring sowing crops in Yiliang county are in the stage of young panicle differentiation. At this time, the crop has strong photosynthesis, vigorous metabolism and large leaf transpiration, which belongs to the critical period of crop water demand, and the water demand during this period accounts for more than 60% of the total water demand in the whole growth period.

In case of dry weather, crop leaves will not be able to carry out normal photosynthesis due to lack of water, which will affect the synthesis and transportation of organic matter, inhibit the normal development of crop branches and spikelets, increase the probability of spikelets degeneration and sterility, and reduce crop yield. Summer drought will hinder the normal heading and flowering of crops, affect grain filling maturity and reduce yield.

The sensitivity of crops to drought disasters is different at different growth stages, and the dry weather in the critical period of water has a great influence on yield. For example, the critical water period of cereal crops such as wheat usually occurs at jointing-heading stage, during which drought will reduce ears and grains. The critical water content of maize generally appears in the "big trumpet mouth" stage before heading, and water shortage will affect the normal development of male flowers. Insect pests, such as locusts, often appear when there is little rain, which affects the quality and yield of crops.