A review of soil temperature under a controlled irrigation system
Temperature is the major driver of the climate change whose effects have taken toll on many sectors including agriculture and non agriculture industries. Different temperature ranges are required for various crops, and the least range of soil temperature at which germination takes place without delay is called minimum soil temperature. The term “Soil temperature” is defined as the measurement of the warmth in the soil, which is one of the most important factors affecting plant growth. The optimum range of soil temperature for plant growth is between 20 and 30°C and the rate of plant growth declines drastically when temperature is less than 20°C (sub optimal) and above 35°C (supra optimal). Therefore, all soil processes are temperature dependent. Consequently, the thermal regime of soil strongly influences the edaphic environment which plays a major role in ensuring crop productivity, sustainability and control of biological and biochemical processes that affects soil organic matter formation; fertilizer efficiency; seed germination; plant development and turgidity, nutrient uptake and decomposition; and disease and insect occurrence. Soil temperature is a cogent factor to be considered for effective irrigation scheduling. Concept of global temperature and its impacts on ecosystem were examined. The relationship between soil temperatures with evapotranspiration, soil infiltration and soil moisture were discussed. This study extended to the effects of soil temperature on physical, chemical and biological properties of soil. Factors affecting soil temperature and methods of soil temperature management were highlighted.
Key words: Global Temperature, Soil Temperature, Soil Properties, Temperature, Soil Process, Soil Management