1. Name:_____________________ ENVICSI HM2B 07162015
III. BIOMES- ECOLOGICAL SYSTEM
Biodiversity
Biodiversityis the variety of different types of life found on earth. It is a measure of the variety of organisms
present in different ecosystems. This can refer to genetic variation, ecosystem variation, or species variation
(number of species) within an area, biome, or planet.
 Terrestrial biodiversity tends to be highest near the equator, which seems to be the result of the
warm climate and high primary productivity.
 Biodiversity is not distributed evenly on Earth.
 It is the richest in the tropics.
 Marine biodiversity tends to be highest along coasts in the Western Pacific, where sea surface
temperature is highest and in the mid-latitudinal band in all oceans.
 There are latitudinal gradients in species diversity.
 Biodiversity generally tends to cluster in hotspots, and has been increasing through time but will be
likely to slow in the future.
Environmental Systems and Societies/Biomes
Biomes
The termbiome
 A collection of ecosystems sharing similar climatic conditions; for example, tundra, tropical
rainforest, desert.
 Biomes usually cross national boundaries (biomes do not stop at a border; for example, the
Sahara, tundra, tropical rainforests).
The distribution, structure and relative productivity of tropical rainforests, deserts, tundra
and any other biome.
HOW MANY BIOMES DO WE HAVE?
Some people say there are only 5 major types of biomes: aquatic, desert, forest, grassland, and
tundra.
Others split biomes further.
Forests are separated into rainforest, temperate forest, chaparral, and taiga; grasslands are divided
into savanna and temperate grasslands; and the aquatic biome is split into freshwater and marine.
AQUATIC BIOMES
 Freshwater
 Freshwater wetlands
 Marine
 Coral reef
 Estuaries
TERRESTRIAL BIOMES:
 Tundra
 Rainforest
 Savanna
 Taiga
 Temperate forest
 Temperate grassland
 Alpine
 Chaparral
 Desert

2. TWO CATEGORIES OF BIOMES:
- There are many different types of biomes on the Earth's surface.
- Each biome is unique in that it has its own weather and temperature patterns, plant species,
and animal species.
- It is important to understand the uniqueness of each biome in order to understand why
certain animals and plants thrive in one area yet would not be able to survive in another.
- Biomes are also verysensitive and each has special needs in order to maintain itself.
- Although there are many types of biomes, they each fit into two categories:aquatic biomes
and terrestrial biomes.
A. Terrestrial Biomes
- Terrestrial biomes are those that occur on dry land.
- These biomes differ in their climate, vegetation, and animal life.
- There are many types of terrestrial biomes but the main biomes include tundra biome, desert
biome, forest biome, and grassland biome.
- The tundra biome is one of extreme weather conditions.
- Temperatures often remain verycold and harsh. Only a few plants and animals can survive
there.
- The Desertbiome also has extreme weather conditions.
- There are two types of deserts, hot deserts and cold deserts.
- Both desert types are verydry and receive verylittle rainfall.
- The Forestbiome is characterized by its humidity and ample rainfall.
- The rain allows verytall trees to grow there.
- There are two types of forest, tropical rainforest and temperate deciduous forest.
- These forests are distinguishable by the types of plants and trees that grow there.
- Grasslands have a lot of varietyamong its plants and animals.
- The plants that grow there include many types of flowers.
- The soil in the grassland is very rich in nutrients so it is easy for many plants to survive there.
- Even though the temperatures in the grassland biome remain pleasant for most of the year, it
does experience a dry season.
- This dry season sometimes results in a drought which makes water scarce for the plants and
animals there.
Terrestrial Biomes
- The biome concept organizes large-scale ecological variation.
- Terrestrial biomes are distinguished primarily by their predominant vegetation, and are mainly
determined by temperature and rainfall.
- Tropical forests are found in areas centered on the equator. Central and South America possess
half of the world’s tropical forests.
- Climate in these biomes shows little seasonal variation, with high yearly rainfall and relatively
constant, warm temperatures.
- The dominant plants are phanerophytes - trees, lianas, and epiphytes.
- Tropical rainforests have an emergent layer of tall trees over 40 m tall, an overstory of trees up to
30 m tall, a sub-canopy layer of trees and tall shrubs, and a ground layer of herbaceous

3. vegetation.
- Tropical forests have the highest biodiversity and primary productivity of any of the terrestrial
biomes.
- The tropical forest biome is estimated to contain over half of the terrestrial species on Earth.
The tropical forest biome is composed of several different sub-biomes, including evergreen rainforest,
seasonal deciduous forest, tropical cloud forest, and mangrove forest.
These sub-biomes develop due to changes in seasonal patterns of rainfall, elevation and/or substrate.
- Tropical Rainforests:
 High productivity
 High precipitation (2500 mm yr¹) throughout the year
 High insolation
 High temperature (26 ʻC)
 Good nutrient cycling = High rate of discomposure
 Highest NPP
-Temperate Forests:
 Medium productivity
 4 seasons (Insolation and temperature varies)
 Good growing season in the summer but limited in the winter
 High temperatures and insolation in the summer = Greater productivity
 Rainfall between 500 and 1500 mm yr¹
 Second highest NPP
-Tundra:
 Low productivity
 Lowest of precipitation (50 mm yr¹)
 Low insulation (Days are shorter)
 Low Temperature
 Poor nutrient cycling because itʼs locked in the permafrost therefore low rate of decomposure
 For 1-2 months the productivity is very high because the sun is up for almost the whole day
- Deserts:
 Very low productivity
 Low precipitation (Under 250 mm yr¹)
 High insolation, but all water is evaporated or absorbed by the ground
 Hot days & Cold nights
 Low nutrient cycle
 Species adapted to survive

4. - Grassland:
 Wide diversity, but low levels of productivity
 Enough precipitation to prevent deserts forming, but not enough to support forests
 Nutrient cycle is sufficient
 Insolation, precipitation and evaporation rates are balanced
 Grass can grow under the surface even in cold periods, waiting to emerge until the ground warms
TERRESTRIAL BIOMES:
 Tundra.
 Rainforest.
 Savanna.
 Taiga.
 Temperate forest.
 Temperate grassland.
 Alpine.
 Chaparral.
B. Aquatic Biomes
- Aquatic biomes are those that occur under water.
- This can be saltwater or freshwater.
- There is saltwater in the ocean and this is where one would find the ocean biome and the coral
reef biome.
- The shallow part of the ocean that contains coral is a part of the coral reef biome.
- The freshwater biome includes areas of land covered in water that contains less than 1% of salt
water.
This includes rivers, lakes, ponds, and wetlands such as swamps and marshes.
Fresh Water Biomes
- Let's start with standing freshwater biomes, from a river to a lake or pond.
- The water doesn't move very quickly here. It gives animals a chance to grow up.
- You'll find larger fish, insects, and plants in this lake. Scientists divide lakes into two major
levels, limnetic (the top), and profundal (the deeper part).
- They even have names for the shore (littoral) and the very bottom on the floor of the lake (benthic).
- You'll find most of the activity in the limnetic zone.
- Fishermen often fish in the limnetic zone.
Salty And Fresh Water Mixing
- Estuaries are the regions where the freshwater meets the saltwater.
- They will always be found near the coast.
- Fresh and saltwater mix constantly in estuaries.
- This mixing allows huge amounts of marine life to exist.
- It turns out that this is a great area for fish to lay their eggs.
- The water is quiet and still and when the fish are tiny, they can hide in the cloudy (brackish) water.
- When you look around you will see all sorts of birds such as cranes and storks and insects who lay
their eggs near the still water also.

5. Right Around The Coasts
- The intertidal zone is where the waves hit the coast.
- Tides are controlled by the gravity of the Moon.
- The Moon causes them to move up and down each day.
- As they rise and fall they leave a patch of coast under the water when the tide is high.
- The same area is dry and exposed when the tide lowers.
- It's usually very rocky here with lots of algae and small creatures.
- You can walk around when the tide is low and find sea urchins, sea stars, and all sorts of birds and
insects looking for food with you.
- Next to the intertidal zones are subtidal zones.
- This zone is always under water along the coasts of continents.
- You can find coral reefs and most of the world's fish in this region.
- You'll also find larger fish because they have more room to swim and more little fish to eat. There are
also huge sandy plains in this subtidal region.
- Because of all of the waves and activity, there is a lot of oxygen in the water to support the wildlife.
Deep In The Ocean
- There comes a point where the floor of the ocean just drops away.
- Now you are in the deep ocean biome.
- Scientists break this biome into three layers.
- At the surface is the euophotic zone.
- There is a large amount of sunlight and oxygen but very few nutrients.
- They all fall to the bottom of the ocean.
- You'll find many small organisms that are photosynthetic.
- As we move down, we get to the bathyal zone.
- The light is very dim. No little organisms are found here, just some fish who feed on the organisms at
the surface.
- At the bottom of the ocean is the abyssal zone.
- This zone is pitch black, with no producers, little oxygen, extremely cold, and high pressure.
- There are living organisms down there.
- They usually feed on the dead stuff that falls from the surface layers. Then, of course, there are the
predators that swim through the murky depths.
Prepared by: rdc