What is the effect of daily range on crop yield?

First, the daily temperature difference is large:

1, high temperature and strong sunshine during the day are beneficial to crop photosynthesis and can produce more nutrients;

2. Low temperature at night weakens the respiration of crops, reduces energy consumption and is beneficial to the accumulation of nutrients; Therefore, the yield of crops is high.

Second, the daily temperature difference is small: the daily temperature difference is small, and the heat and livestock products are small. However, agriculture, which mainly works in the open air, still relies on the weather to reduce energy consumption: on the contrary, the most suitable temperature for photosynthesis is 20~C-30~C, which provides light; Low temperature at night; Therefore, the high yield of crops is a modern society. In short; The accumulated value of heat in an area not only determines the maturity and production potential of crops in this area, but also determines the weak respiration of crops, planting system and development garden.

Third, in agricultural production, sometimes a large daily range is needed, which is beneficial to high yield of crops. Because a large diurnal range means that the temperature is higher during the day and lower at night, so that the photosynthesis of leaves is strong during the day and more carbohydrates are produced, while at night, the respiratory consumption is less and the accumulation is more, and the crop yield is high and the quality is good.

Knowledge expansion:

The factors that affect the daily temperature range are:

(a) Latitude: The daily temperature difference decreases with the increase of latitude. This is because the change of sun height in a day decreases with the increase of latitude. The daily temperature difference in tropical areas is about 65438 02℃. The daily range of temperate zone is 8.0 ~ 9.0℃; The daily temperature difference of polar circle is 3.0 ~ 4.0℃.

season

Generally, the daily range in summer is greater than that in winter, but in the middle and high latitudes, the maximum daily range in a year appears in spring. Because in summer, although the height angle of the sun is large, the sunshine time is long and the temperature is high during the day, the daily temperature difference in summer is not as large as that in spring because of the short day, short cooling time and high temperature at night in the middle and high latitudes.

terrain

The daily temperature range in low concave areas (such as basins and valleys) is greater than that in convex areas (such as hills). The terrain is low and concave, the contact area between air and the ground is large, and the ventilation is poor. At night, it is often the place where cold air sinks and meets, so the daily temperature difference is large. On the other hand, because of high wind speed, strong turbulence, fast heat exchange and small daily temperature difference, the flat land is in between.

(d) Characteristics of underlying surface

Because of the different thermal characteristics and solar radiation absorption capacity of the underlying surface, the daily temperature difference is also different. The daily temperature difference on land is greater than that on the sea, and the farther away from the sea, the greater the daily temperature difference. The daily temperature difference of sandy soil, dark soil and dry loose soil is greater than that of clay, light soil and wet compact soil respectively.

weather

The diurnal temperature range in sunny days is greater than that in cloudy days (rainy days), because the solar radiation is strong in sunny days, the ground temperature is strong, and the effective radiation on the ground is strong at night. The daily temperature difference in windy days is small.