Trapped In Time - Chapter 79

“We got a lot of information from the grass, I think we need to ask the Lake to tell us about itself,” Sherpa said with a smile. He had the impression that the water body would not have any chip placed near its edge or in the water.

“Yes, I think it is a very good idea,” responded Aalvin with a twinkle in his eye. He knew what was going through Sherpa’s mind.

“I will just ask it and it will answer?” asked Sunny with great curiosity.

“Yes, you may try asking,” responded Aalvin.

“Mr. Lake can you tell us something about yourself?” he asked.

“Yes, I will tell you all I can,” was the reply he got and the voice seemed to come from somewhere in the middle of the lake.

The lake was not huge, quite small actually. Some fish could be seen swimming in it and a few frogs were basking in the sun while sitting on the leaves of the lotus plants.

“We will talk to you first and then talk to the fish and the frogs as well as the daffodils and the lotus plants,” said Sunny.

“We will talk to the birds and the squirrels and the rabbits as well as the trees later on,” said Ben.

“I will tell you all the information about lakes that had been fed into me via the chip. Then you can ask me questions. I will respond if the answers are within my program.”

“Ok everyone, please listen carefully. I am starting my lecture.” the Lake said.

Basically, a lake is a basin-like area filled with water and surrounded by land. It may have a river or stream or rivulet which functions to feed or drain the lake. Lakes lie on a piece of land and are not part of the ocean. Hence, they are different from lagoons and are also larger and deeper than ponds. Lakes can be contrasted with rivers or streams, which are usually flowing.

Then there are Natural lakes and Man-made lakes.

Natural lakes are found mostly in the mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found along the courses of mature rivers. In some parts of the world, there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.

Many lakes are artificial or man-made and have been constructed for industrial or agricultural use, for hydro-electric power generation or domestic water supply, or for aesthetic, recreational purposes, or other activities.

The word lake comes from Middle English lake (“lake, pond, waterway”), from Old English lacu (“pond, pool, stream”).

There is no term to differentiate the difference between lakes and ponds. The limnologists define lakes as a larger version of a pond, which can have wave action on the shoreline or where wind-induced turbulence plays a major role in mixing the water column. None of these definitions completely excludes ponds and all are difficult to measure. For this reason, simple size-based definitions are increasingly used to separate ponds and lakes.

One hydrology book proposes to define the term “lake” as a body of water with the following five characteristics:-

1. It partially or totally fills one or several basins connected by straits, has essentially the same water level in all parts (except for relatively short-lived variations caused by wind, varying ice cover, large inflows, etc.).

2. It does not have the regular intrusion of seawater.

3. A considerable portion of the sediment suspended in the water is captured by the basins (for this to happen they need to have a sufficiently small inflow-to-volume ratio).

4. The area measured at the mean water level exceeds an arbitrarily chosen threshold (for instance, one hectare).

5. With the exception of the seawater intrusion criterion, the others have been accepted or elaborated upon by other hydrology publications.

The majority of lakes on Earth are fresh water, and most lie in the Northern Hemisphere at higher latitudes. Canada, with a deranged drainage system, has an estimated 31,752 lakes larger than 3 square kilometers and an unknown total number of lakes estimated to be at least 2 million.Finland has 187,888 lakes 500 square metres (5,400 sq ft) or larger, of which 56,000 are large (10,000 square metres (110,000 sq ft).

Most lakes have at least one natural outflow in the form of a river or stream, which maintain a lake’s average level by allowing the drainage of excess water. Some lakes do not have a natural outflow and lose water solely by evaporation or underground seepage or both. They are termed endorheic lakes.

Evidence of extraterrestrial lakes exists as indicated by the Cassini Probe observing the moon Titan. NASA had announced that evidence of lakes filled with methane existed on the moon Titan of the planet Saturn.

Globally, lakes are greatly outnumbered by ponds: of an estimated 304 million standing water bodies worldwide, 91% are 1 hectare (2.5 acres) or less in the area (see definition of ponds).[16] Small lakes are also much more numerous than large lakes: in terms of area, one-third of the world’s standing water is represented by lakes and ponds of 10 hectares (25 acres) or less.[citation needed] However, large lakes account for much of the area of standing water with 122 large lakes of 1,000 square kilometers (390 sq mi, 100,000 ha, 247,000 acres) or more representing about 29% of the total global area of standing inland water.[citation needed]

Classification of lakes

In 1957, Hutchinson published a monograph that is regarded as a landmark discussion and classification of all major lake types, their origin, morphometric characteristics, and distribution. He presented in it a comprehensive analysis of the origin of lakes and proposed what is a widely accepted classification of lakes according to their origin. This classification recognizes 11 major lake types that are divided into 76 subtypes. The 11 major lake types are tectonic lakes, volcanic lakes, landslide lakes, glacial lakes, solution lakes, fluvial lakes, aeolian lakes, shoreline lakes, organic lakes, anthropomorphic lakes, and meteorite (extraterrestrial impact) lakes.