THE HYDROSPHERE

# ECOLOGY

WHAT IS HYDROSPHERE?The hydrosphere is the liquid water component of the Earth. It includes the oceans, seas, lakes, ponds, rivers and streams. It covers about 70% of the surface of the Earth and is the home for many plants and animals.A total amount of water on a planet.It includes water that is on the surface of the planet, underground, and in the air. A planet's hydrosphere can be liquid, vapor, or ice.

Hydrosphere is present on Earth in three forms:

Solid :is one of the four fundamental states of matter (the others being liquid, gas, and plasma). It is characterized by structural rigidity and resistance to changes of shape or volume.

Liquid : is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, and plasma), and is the only state with a definite volume but no fixed shape.

Gas : A pure gas may be made up of individual atoms (e.g. a noble gas or atomic gas like neon), elementsl molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide).

WATER>Water is found in many places on Earth including

on the surface of the planet, within rocks below the surface, and in the atmosphere.

Water travels between different areas of the Earth through the water cycle.

About 70% of the Earth surface is covered with water, and most of that is the ocean.

Only a small portion of the Earth's water is freshwater, which is found in rivers, lakes, and groundwater.

***Freshwater is needed for drinking, farming, and washing. In addition to liquid water, water is also present on Earth in the form of ice. Without water, life as we know it would not exist.

“water”

WHAT IS HYDROLOGICAL CYCLE?

THE HYDROLOGICAL CYCLE

• This is some times called the water cycle.• Water is the most important chemical of life for

all living organisms on earth.• Water in the atmosphere is usually in form of

vapor but condenses to liquid water and can solidify when temperatures are 00C to form ice.

• Ninety three percent of water on earth is in solid state mainly comprising the ice caps and glaciers of Polar Regions.

The characteristics of the ocean which affects its motion are its temperature and salinity.

• >Warm water is less dense or lighter and therefore tends to move up toward the surface.

• >Colder water is more dense or heavier and therefore tends to sink toward the bottom.

• >Salty water is also more dense or heavier and thus tends to sink.

• >Fresh or less salty water is less dense or lighter and thus tends to rise toward the surface.

“WATER”

WHAT IS LENTIC?

LENTIC

. Lentic refers to standing or relatively still water, from the Latin lentus, which means sluggish.

Lentic ecosystems can be compared with lotic ecosystems.

Lentic systems are diverse, ranging from a small, temporary rainwater pool a few inches deep to Lake Baikal, which has a maximum depth of 1740 m. The general distinction between pools/ponds and lakes is vague, but Brown states that ponds and pools have their entire bottom surfaces exposed to light, while lakes do not. In addition, some lakes become seasonally stratified Ponds and pools have two regions: the pelagic open water zone, and the benthic zone, which comprises the bottom and shore regions. Since lakes have deep bottom regions not exposed to light, these systems have an additional zone, the profundal.These three areas can have very different abiotic conditions and, hence, host species that are specifically adapted to live there.

Example of lentic

WHAT is LOTIC?

“LOTIC” Rivers and streams rarely display the vertical stratification

patterns found in standing bodies of water because of their turbulent flow.

Although slight differences in temperature can exist between the surface and bottom waters of deep lotic systems, the greatest changes take place as water moves downstream.

Flowing water systems frequently possess greater habitat heterogeneity than lentic systems.

They also are more permanent ecosystems on a geological or evolutionary scale.

Both heterogeneity and permanence tend to increase species diversity.

Example of lotic

WHAT IS WETLAND?

“WETLAND”• A wetland is a land area that is saturated with water, either

permanently or seasonally, such that it takes on the characteristics of a distinct ecosystem.

• Wetlands play a number of roles in the environment, principally water purification, flood control, and shoreline stability.

• Wetlands are also considered the most biologically of plant and animal life. 

• Wetlands occur naturally on every continent except Antarctica, the largest including the Amazon River basin, the West Siberian Plain, and the Pantanal. 

• The water found in wetlands can be freshwater, brackish, or saltwaterdiverse of all ecosystems, serving as home to a wide range

EXAMPLE OF

WETLANDS

Three basic kinds of freshwater ecosystems exist:

• Lentic :Slow-moving or till water like pools, lakes or ponds.• Lotic :Fast-moving water such as

streams and rivers.•Wetlands :Places in which the

soil is inundated or saturated for some lenghty period of time.

WHAT IS A MARINE ECOSYSTEM?

“MARINE”• Marine is an adjective for things relating

to the sea or ocean, such as marine biology, marine ecology and marine geology.

• As a noun it can be a term for a kind of navy, those enlisted in such a navy, or members of troops attached to a navy, e.g. the United States Marine Corps.

EXAMPLE OF MARINE

“COASTAL”• A coastline or a seashore is the area where land

meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the Coastline paradox.

• The term "coastal zone" is a region where interaction of the sea and land processes occurs. Both the terms coast and coastal are often used to describe a geographic location or region; for example, New Zealand's West Coast, or the East and West Coasts of the United States.

PELAGIC COAST• A pelagic coast refers to a coast which fronts the

open ocean, as opposed to a more sheltered coast in a gulf or bay.

• A shore, on the other hand, can refer to parts of the land which adjoin any large body of water, including oceans (sea shore) and lakes (lake shore).

• Similarly, the somewhat related term "bank" refers to the land alongside or sloping down to a river (riverbank) or to a body of water smaller than a lake. "Bank" is also used in some parts of the world to refer to an artificial ridge of earth intended to retain the water of a river or pond; in other places this may be called a levee.