Effect of Light and Solar Radiation on Aquatic Environments

Flashcards covering the effects of light, solar radiation, penetration depths, marine zones, and temperature on aquatic ecosystems based on Integrated Sciences Lesson 1-8.

In what form does the electromagnetic spectrum propagate, and how do electromagnetic waves differ from one another?

The electromagnetic spectrum propagates in the form of electromagnetic waves that differ from each other in wavelength ($\lambda$) and frequency ($\nu$).

What are the spectrum colors that constitute visible light, listed in order?

Red, Orange, Yellow, Green, Blue, Indigo, and Violet.

What two processes occur when sunlight penetrates the surface of water?

A part of the sunlight is absorbed by the water, suspended materials, and aquatic plants, while the other part is scattered as the light penetrates to the deep.

How does the angle of sun rays striking the water surface affect the amount of light that penetrates?

The amount of light penetrating the water surface is high when sun rays strike perpendicularly, whereas it decreases when sun rays strike at an angle.

Which ocean zones are defined by the gradual decrease in light intensity as water depth increases?

The sunlit (surface) zone, the twilight (mid-depth) zone, and the dark (deep) zone.

According to this diagram, how is the marine environment classified into zones by depth and topography?

It is divided horizontally and vertically into the Tide Zone, Shallow Zone (down to $200\,\text{m}$), Oceanic Zone (Open Water Zone), Sunlit Zone, Dark Water Zone, Ocean Floor Zone, and the Deep (Abyssal) Zone ($6000-9000\,\text{m}$).

At what depth does water absorb almost all of the infrared energy from sunlight?

At a depth of $10\,\text{cm}$ from the surface.

What proportion of visible light energy is absorbed by water at a depth of $10\,\text{m}$?

Water absorbs more than $50\%$ of the visible light energy.

How much visible light reaches a depth of $100\,\text{m}$ in clear tropical waters, and which color range does most of it belong to?

Only about $1\%$ of visible light reaches a depth of $100\,\text{m}$, and most of it is in the blue range.

How does water selectively absorb and scatter different colors of the spectrum?

Water absorbs warm colors such as red and orange (which have long wavelengths) and scatters cooler colors (which have short wavelengths).

What key difference in light penetration between ocean waters and shallow waters is illustrated in this figure?

In clear ocean waters, light penetrates down to approximately $200\,\text{m}$ with blue light penetrating the deepest, whereas in shallow waters, light penetration is restricted to shallower depths of around $50\,\text{m}$ due to absorption.

To what depth can algae and aquatic plants grow in clear waters compared to turbid waters?

In clear waters, they grow well down to a depth of $100\,\text{m}$, but in turbid waters (containing sediments or phytoplankton), they are found closer to the surface.

Why do coral reefs thrive in warm, shallow waters near the equator?

Solar radiation is available year-round near the equator, which stimulates the growth of symbiotic algae living inside coral tissues that provide them with food.

Which fish species prefer warm tropical waters, and which species prefers cooler waters farther from the equator?

Tropical fish such as tuna and barracuda live in warm waters, while Cod prefers cooler waters farther from the equator.

How does the winter season in polar regions impact photosynthetic activity and food availability?

Solar radiation is low or nonexistent during winter, causing photosynthesis rates to decrease significantly, which reduces the availability of food for marine organisms.

What role does the Gulf Stream play in regulating climate and marine diversity?

The Gulf Stream carries warm water from the equator toward the North Atlantic Ocean, creating a moderate climate in regions like Western Europe and enhancing marine life diversity there.