2. Energy flow in the ecosystem
Ecological succession
Food chains , food web & ecological
pyramids
TOPICS
3. The community of independent
organisms along with
the inorganic components (chiefly soil,
water, air, and rocks) that make up our
ecosystem/environment
4. ENERGY CYCLE
Energy cycle is based on the flow of
energy through the ecosystem That is
flow/transfer of energy from one
body to another for eg 1,000 carrots
to support 100 rabbits, 10 owls, and
one hawk. mainly sunlight is at the
apex of all energy cycle
5. Water cycle is common to us. The rain water which
falls on ground flow into rivers/sea or falls directly
into the sea gets evaporates due to solar energy and
some rainwater which percolates into the ground is
drawn up by plants. These water then transpired
from leaves as water vapor. This vapors are lighter
then air so they rise high and forms clouds as
clouds rise higher. The vapor condenses and
changes into droplets which falls on the land as
rain
6. The Carbon cycle
The oxygen on which the whole mankind & animal kind
depend is generated through this cycle. In the
atmosphere carbon occurs as carbon dioxide (co2). In
the presence of sunlight plants take carbon dioxide from
atmosphere through their leaves the carbon dioxide
from soil is also absorbed by their roots. In the presence
of sunlight they are able to to form carbohydrates that
contain carbon this process is known as photosynthesis.
In these process plants releases oxygen into atmosphere
on which animals depend for their respiration animals
release carbon dioxide during respiration so they return
fixed carbon to the soil and also when they die they
return their carbon to soil
7. The Oxygen cycle
Oxygen cycle and carbon cycle is
linked with each other oxygen is
absorbed by plants and animals
from air during their respiration and
gives carbon dioxide these carbon
dioxide is absorbed by plants during
photosynthesis and give out oxygen
8. Herbivores feed on plants carnivores feed on
herbivores thus the bodies of dead plants and
animals or their wastes material is broken
down by worms &insects mostly beetles and
ants these small soil animals breaks the waste
material into smaller bits on which microscopic
bacteria &fungi can act this material is broken
down further into nutrients that plant absorb &
use for their growth in this manner nutrient are
recycled back from animal to plants
9. Ecological succession is a process
through which ecosystem tends
to change over a period of time
succession can be related to
seasonal environmental changes
which create change in the
community of plants and
animals living in the ecosystem
11. Primary succession
Successional dynamics beginning with
colonization of an area that has not been
previously occupied by an ecological community,
such as newly exposed rock or sand surfaces,
lava flows, newly exposed glacial tills, etc., are
referred to as primary succession.
12. Secondary succession
Successional disturbance or removal of a pre-
existing community are called secondary
succession. Dynamics in secondary
succession are strongly influenced by pre-
disturbance conditions, including soil
development, seed banks, remaining organic
matter, and residual living organisms.
Secondary succession is much more
commonly observed and studied than
primary succession.
13. Cyclic succession
Unlike secondary succession, these types of
vegetation change are not dependent on
disturbance but are periodic changes
arising from fluctuating species
interactions or recurring events. These
models propose a modification to the
climax concept towards one of dynamic
states.
14. Factors Influencing
Succession
The trajectory of successional change can be influenced
by site conditions, by the interactions of the species
present, and by more stochastic factors such as
availability of colonists or seeds, or weather conditions at
the time of disturbance. Some of these factors contribute
to predictability of succession dynamics; others add more
probabilistic elements. In general, communities in early
succession will be dominated by fast-growing, well-
dispersed species As succession proceeds, these species
will tend to be replaced by more competitive species.
15. Food chains, food web and
ecological pyramids
The transfer of energy from the source in plants
through a series of organisms by eating and being
eaten constitutes food chains. The
interconnection between different food chain is
known as food webs. Each step of the food web is
called tropic level these tropic level to gather form
the ecological pyramid
16. Food Chains
Food chains are the sequence of feeding
relationships through which plants and animals
depend on each other for food. Food provides the
nutrients plants and animals need to build and
repair their body parts, and the energy they need
to grow and function. There are countless food
chains involving different plant and animal
species in a variety of habitats all around the
world. Every plant and animal belongs to at least
one food chain, and these chains can be simple or
very complex.
17. *In an ecosystem there are a very
large number of interlinked food
chains, these forms a food web
*
18. Ecological pyramids
The green plants the producers in
ecosystem form the first trophic
level in food pyramid. The
herbivores that eat plant are at the
second trophic level and are called
primary consumers the predators
that feed on them form the third
trophic level and called carnivores
they are at the apex of food
pyramid