Difference Between Evaporation and Transpiration (With Table)

Evaporation is a process where the liquid form of water on the surface converts into gaseous vapors and goes into thin air in the presence of energy (heat of the sun). This process occurs day and night, leaving the surface extremely dry. This process is not bounded to any particular surface. It occurs everywhere.

Transpiration is a process of water evaporating from the plant cells through opening pores on the leaves and stomata, this (pores) also helps them to control the release of water, and it completely depends upon the humidity of the air. This process does not take place at night, and also it leaves the surface wet. 

Comparison Table Between Evaporation and Transpiration

What is Evaporation?

It is a process of water/liquid turning into a gaseous form in the presence of sunlight. The factors that affect Evaporation are:

1. Temperature: The temperature of the liquid affects the process as the cold liquid will evaporate slowly as compared to the hot liquid.
2. Presence of sunlight: the presence of strong sunlight liquid evaporates very quickly.
3. It is observed that pure and plain water evaporated fats as compared to salty or sweet water.
4. Air sometimes also plays an important role as clothes dry fast in the presence of wind.
5. The concentration of vapor in the air, if there is more concentration of vapors in the air already, then it will take time for the liquid to evaporate.

Applications of Evaporation:

1. In Industry: in printing, coating, salts recovery, and drying of paper, cloth and chemicals.
2. In Labs: for spectroscopy and chromatography.
3. Others: for drying clothes, making clay containers, drying hair, etc.

It is one of the processes from the water cycle, it takes place where water is present, whether it’s a pond, river, floor, etc., the water after evaporating goes into the air, and then the process of precipitation takes place.

What is Transpiration?

It is a process of water evaporating from the plants into thin air or atmosphere. The various types of Transpiration are:

1. Stomatal Transpiration: under this type, most of the water evaporated from the stomata through the open pores.
2. Lenticular Transpiration: under this type, the water evaporated from the lenticels (small pores on twigs or bark of branches). Very few plants have Lenticels. Therefore a very less amount of water is evaporated.  
3. Cuticular Transpiration: under this type, water evaporates through the cuticle (sticky covering on leaves surface). At times stomata are closed; therefore, water is evaporated through it.

Factors Affecting the Process

1. Sunlight along with atmospheric pressure.
2. Amount of water present in the plant.
3. Number and distribution of stomata.
4. Humidity and Temperature.
5. Speed or velocity of the wind.

Significance

1. Helpful in conducting both minerals and water.
2. Maintain the balance of water.
3. Keeps osmosis rigid.
4. Helpful in the upward movement of water.
5. Responsible for turgidity of the cells. 
6. Helpful in the cell division process.
7. Gives a cooling effect.
8. Responsible for maintaining the moist on leaves.

Along with all the above significance, there are some drawbacks, such as for this process plant requires a large amount of water and plants release a very large amount of energy in the atmosphere.

Main Differences Between Evaporation and Transpiration

1. Evaporation is a process that can take place on any surface, whereas Transpiration only takes place in plants, i.e., in plant cells. This means that in Evaporation, water is lost from the surface, but in Transpiration, water is lost from plant cells. Also, Evaporation occurs from the entire surface, but Transpiration only occurs through stomata, cuticle, or lenticels.
2. They both are different types of processes. Evaporation is a Physical Process, and Transpiration is a Biological Process.
3. Both of them take their own time to complete the process. Evaporation is a fast process. Therefore, it gets completed early. On the other hand, Transpiration is a comparatively slow process and takes time to complete.
4. Both of them involve different types of tissues or organisms, Evaporation involves only non-living matter, but Transpiration involves only living tissue.
5. Evaporation is a process that takes place throughout the day (day as well as night), but Transpiration is a process that takes place only during the day.
6. The surface, even after the Transpiration process, remains wet, but in the case of Evaporation, the surface becomes completely dry.
7. The transpiration process is associated with the uptake of minerals and nutrients, but the Evaporation process is not associated with any of this.
8. Transpiration is regulated by pH, temperature, Carbon dioxide, light, concentration, and hormones and is controlled by Osmotic and Water Potential, but Evaporation neither has such regulations nor control. It is an independent process.

Conclusion

Both the Evaporation and Transpiration processes are associated with the water. Both of them link the terrestrial and atmospheric hydrological processes and are important factors of the hydrological cycle. Both of them have a similarity of water turning from liquid (from the surface) to gaseous form, i.e., water vapors. (in the atmosphere) and loss of water from both of these processes together is called evapotranspiration. 

These processes must take place regularly to maintain the balance of the ecosystem. Sometimes transpiration is considered a type of evaporation that takes place in plant cells as in this water is getting evaporated in the atmosphere.

References

1. https://repository.rothamsted.ac.uk/item/8v5v7/evaporation-and-environment
2. https://www.annualreviews.org/doi/pdf/10.1146/annurev.pp.19.060168.001235
3. https://library.wur.nl/WebQuery/wurpubs/412958
4. https://www.sciencedirect.com/science/article/abs/pii/S0168192314000203