Temperature and Soil Moisture. Their Interaction and Effect on Plant Growth
Posted on 12 Apr 2018
By: Olga Makarova,
PR Manager, OpenWeather
Crop farming covers around 40% of the globe and uses 85% of its fresh water.
Often, in countries where agriculture constitutes the principal occupation of farmers, due to drought and overpopulation, they find themselves in a constant battle to maintain everyday resources such as food and water etc. In such cases, productivity and crop prices assume critical importance. And they, in turn, depend primarily on atmospheric factors and soil conditions.
Correct assessment of such indices as soil moisture and temperature is crucially important to understanding the interaction between the Earth’s surface and atmosphere.
Air temperature is the most important factor, determining as it does the temperature of plants themselves. It has a huge effect on the physiological condition of plants, connected as it is with photosynthesis, respiration, and other processes. Temperature conditions determine the rate and length of individual phenological phases in plant growth and development, for example the accumulation of sugar and acids in grapes.
The temperature factor to a large extent operates through soil temperature. The sun’s rays barely heat the air due to its minimal capacity for heat storage. They reach the earth, heat its surface, and it is from this that the air then warms up.
In fact, it is always the lower, ground level which ends up being warmed up the most. Heating of the upper layers is brought about by convection whereby warm air rises and cold air sinks. The surface of the soil is the most active regarding this, as it warms up a great deal during the day and cools down at night.
Temperature conditions for the ground level layer of air are closely connected to soil moisture.
Soil temperature is an important variable in the water and energy cycle as it helps to determine how much precipitation is distributed to surface run-off deposits and infiltration components, as well as the distribution of incoming solar and long-wave radiation to outgoing long-wave radiation, and of ground heat flux.
Understanding the interaction between soil moisture and surface temperature enables the effectiveness of irrigation systems to be assessed, and evaporation and other moisture losses to be forecast.
There are several approaches to soil condition evaluation, the most effective being remote soil evaluation: technology which helps farmers give the necessary attention to farms located far away from their residences. This is one of the methods with powerful potential for agriculture, which can stave off the problems affecting productivity in crop cultivation.