Department of

BDU Architecture

Urban Ecology
What Is Ecology?
• Ecology is the scientific study of the relationship and interactions
between organisms and their environment.
• The term ecology is derived from a Greek word Oekologie where
“oikos” meaning “household” and “logos” means “the study of”.
• It is a science of relationships.

• To understand these relationships, ecology must encompass

diverse aspects such as natural events, energy flow and human
activities on Ecosystems.
What do you mean by environment ?

Environment ?
What do you mean by environment ?
• Environment means anything that surrounds us.

Biotic Elements Abiotic Elements

Cultural Elements
What do you mean by environment ?
Atmosphere
Physical
Hydrosphere
Environment
Lithosphere

Floral
Biological
Faunal
Environment Environment
Microbial

society
Cultural Economy
Environment
Politics
What do you mean by environment ?

I. Biotic elements :- all living organisms that in inhabiting the

earth (plants, animals, insects, etc)
II. Abiotic(Physical) elements :- non living part of the
environment (light, soil, temperature…)and also molecules
like carbon, nitrogen..
III. Cultural element :- The interaction between human and
environment also influence the ecosystem.
What do you mean by Levels of ecological organization ?
• Levels of organization is a system that makes looking at ecology
simpler by classifying the environment in different levels. The five
levels of organization are: organism, population, community,
ecosystem, and biosphere.
What do you mean by Levels of ecological organization ?
Organism
Is the individual living thing such as animal, plant, fungi etc…
What do you mean by Levels of ecological organization ?
Population
 Population is a group of individuals with same species that coexist
in space and time, interact with each other, and interbreed.
 Various forms of competition and cooperation have impacts for the
general development of the group.
 The growth potential of a
population is usually very high,
but it always encounters
obstacles in the form of limiting
factors.
Distribution
 Environmental factors ( climate, geography, and soil composition)
determine the distribution of species in different biomes.
 The individuals of a population in a given environment may be
distributed in three different ways
 Random
The distribution is irregular. The location of one individual does not
affect the rest.
 Uniform
Individuals are scattered in a uniform, or even, manner.
Consequently, the presence of one does not diminish the probability of
finding another nearby.
 Grouped
Individuals are found in groups. The presence of one individual
therefore increases the probability of finding another nearby.
What do you mean by Levels of ecological organization ?
Community
The community is a collection of populations of different species that
share a common environment and interact with each other.
What do you mean by Levels of ecological organization ?
Habitat
 The place where an organism or a
population lives.
Niche
 Each species occupies a niche in the
community.
 A niche is the role the species plays,
includes the type of food it eats, where
it lives, where it reproduce and its
relationship with others.
What do you mean by Levels of ecological organization ?
Ecosystem
Ecosystems include the populations of living things that make up a
community and their interactions with the nonliving elements of the
environment.
• Food webs are established in each
ecosystem.
• There are primary producers,
primary and secondary consumers,
and decomposers.
• The energy flow in such food webs
begins with the Sun.
What do you mean by Levels of ecological organization ?
Biosphere
 It is a global sum of all ecosystem
 Biosphere contains the combined portions of the planet in which
all of life exist, including land, water and atmosphere
Feeding Relationships
• Organisms in their natural habitats represent a pronounced feeding
relationship that is, what they feed on and what feeds on them. This
is because they require energy to survive, reproduce and grow.
• There are producers and consumers. Producers are organisms that
are able to produce their own organic food.
• Energy flow through an ecosystem in one direction, from the sun or
inorganic compounds to producers and then to various consumers.
Feeding Relationships
• Food Chains are a series of steps in which organisms transfer
energy by eating or being eaten.
• Food webs show the complex interactions within an ecosystem.
Each step in a food chain or web is called a trophic level.
• Producers make up the first step,
consumers make up the higher
levels.
Symbiotic Relationships
• Commensalism: One species benefits, one is unharmed.

• Mutualism: both species benefit.

• Parasitism: one species benefits, one is harmed or dies.

Nutrient cycle
• Cycling maintain balance in the environment.
• The three main cycles
1. Water cycle
Nutrient cycle

2. Carbon cycle
Nutrient cycle
Effects of Human Activities on Carbon Cycle
 We alter the carbon cycle by adding excess CO2 to the atmosphere
through:
 Clearing vegetation faster than it is replaced.
 Composition of fuel for vehicles
 Carbon emission from constructions
Nutrient cycle
2. Nitrogen cycle
Nutrient cycle
Effects of Human Activities on the Nitrogen Cycle

 We alter the nitrogen cycle by:

 Adding gases that contribute to acid rain.

 Adding nitrous oxide to the atmosphere through farming

practices which can warm the atmosphere and deplete ozone.
 Contaminating ground water from nitrate ions in inorganic
fertilizers.
Importance of ecology
 It enhances energy conservation
 It promotes eco-friendliness
 It allows for better resource allocation
 It helps with minimize disease

As more and more people realize their potential impact on the

environment, they become more welcoming of environmentally-
friendly ideas and proposals. The governments of the world are
scrambling to create green and eco-friendly measures that will help
produce energy in a sustainable way.
Principles of Ecology
Fundamental Ecological principles
 Under line base for Ecological principles
• Adaptation of species
• Conception and transfer of energy
• Cycling of substances
• Evolution and distribution of plants and animals
• Interrelation among the organisms
• Interaction between organisms and physical environment
Fundamental Ecological principles
1. The sun is the ultimate source of energy for most ecosystems.
 Solar radiation is the main driving force of the ecosystem and
its trapped by green plants through the process of photo
synthesis.
 The energy flow in ecosystem is unidirectional and non cyclic.
 The energy pattern and energy flow are governed by the low of
thermodynamics.
 First law of thermodynamics states that the energy can neither
be created nor destroyed. It can however be transformed from
one form to the other.
 Second law of thermodynamics states that during this
transformation some amount of energy is always lost in the
form of heat.
…con
 …con
2. Chemical nutrients cycle repeatedly while energy flows through an
ecosystem.
 The Organic and inorganic substances are circulated among
the various components of biosphere though a series of
closed system of cycles.
3. Organisms interact do things to each other in ways that influence
their abundance.
 Individual organisms can eat one another, compete for
shared resources, and help each other survive.
 Each pair of species in an ecosystem can be characterized
by the kind and strength of these interactions, measured as
their contribution.
 …con
4. Ecosystems are organized into webs of interactions.
 The abundance of a population is influenced by the chains of
interactions that connect it to the other species in its ecosystem.
 This often leads to complex behavior, and a key challenge in
ecology is to determine what patterns of abundance and
diversity can be predicted.
5.The ecosystem is mainly modified by human through the exploitation of
natural resources.
 Human beings reduce ecological diversity and complexity by
removing a host of biotic communication.
 Humans are currently changing the climate, re-arranging its
chemistry, decreasing populations of food, moving around its
species, and decreasing its diversity.
 …con
6. Ecosystems provide essential services to human populations.
 These include products like timber, fiber and food, regulating
water and air quality, and cultural benefits like recreation. A key
goal of ecology is to preserve ecosystem services.
7. Nothing actually disappears
 Nothing actually disappears all the materials are rearranged and
recycled though a series of cycling path way in the nature of
environment.
8. All living organisms and physical environment are mutually reactive.
 …con
9. The ecosystem under goes the process of successional changes
 The process where plants & animals of a particular area are
replaced by other more complex species over time..
 During succession some species colonize an area and their
population become more numerous whereas populations of other
species decline and even disappear.
Individual Assignment

 What do you fill about your living environment?

• Write your personal perception on one A4 paper.
• Present it in five minutes
• The report paper will be submitted on time