Almost 77% of nature as we know it, is water.
Water is termed as the life line for all living things. Generally speaking it covers 3/4th of the earth’s surface and found in all three states i.e. solid (ice, snow), liquid (water), and gas (clouds, fog, water vapor). Clouds are an aerosol of water droplets or water crystals and so is the fog but in a way low lying cloud. When we say that water is the life line of all living things, there are quite a few considerations like; i) a greater part of all living things consists of water, ii) from evolutionary point of view, life originated in water and evolved towards terrestrial environments, iii) water is required to sustain all kinds of life, iv) water drives the turbines to generate electricity, v) it is a medium of navigation and transportation, vi) it is essential component of cooling systems, and vii) last but not the least, access to water may be a cause of conflicts in years to come, and so on.
What we often do not mention or neglect while talking about water is its importance in some other terms as well. The energy required to run bio-systems and the oxygen we breath are both derived from water. We all know that life on this planet is solely dependent on photoautotrophs i.e. organisms that synthesize food using sunlight (photons to be precise) through the process of photosynthesis. The energy we attribute to sun is in fact deployed to run the system of photosynthesis that produces energy-rich compounds. This process is endowed to both terrestrial plants, some specialized microorganisms (bacteria and microalgae) as well as to marine macro-algae (for example kelps).
The solar energy becomes part of the living system through water in a relatively complex manner. Water that is composed of molecules of hydrogen and oxygen in 2:1 ratio is lysed (photolysis) into its components generating at the same time electrons that run through the photosynthetic electron system. Hydrogen released becomes part of the complex organic molecules that are the so-called storehouse of metabolizable energy. More importantly, oxygen required to run the metabolic processes, especially respiration (process through which stored energy is released for used by the living systems), and thus a basic requirement to sustain life, originates from water (Figure 1).
It is not only the significance of water as a requirement for life, but mere aesthetics make water an astounding gift of nature. While bodies of water whether flowing or stagnant present most beautiful natural scenes or as an essential component of the scenery and landscape, a single droplet of water could be as scenic as one could imagine or visualize.
We all observe on vegetation in our surroundings. It is water in the form of droplets that appear on thin, exposed objects in the morning or evening due to condensation. Technically speaking, as the exposed surfaces (especially the plant leaves) cool by radiating heat, atmospheric moisture condenses at a rate greater than that at which it can evaporate thereby resulting in the formation of water droplets i.e. dew.
To some, it is good to have an early morning walk on dew. For others, it is the beauty of nature and has to be observed and registered with a passion. Of course beauty lies in the eyes of the observer; a common saying. But passionate observer, not only see the beauty but appreciate it and let others appreciate as well. Present day access to information technology based media, makes it possible to share the beauty. Herein are presented, some interesting and fascinating images of water drops, acquired by surfaces (mainly plant leaves) as dew or in the form of sprinkled water. Have a look, enjoy, and appreciate the unlimited gifts of nature; cool for the eyes.
* The writer (a plant scientist) has provided first-hand photographs (except for one) taken by himself from his experimental site..
Note: The author retired as Chief Scientist from Pakistan Atomic Energy Commission.