This document discusses concepts related to population growth and ecological succession. It begins by explaining population growth curves, including 'S' and 'J' curves, and the factors that influence population size, such as limiting factors and carrying capacity. It then covers population regulation, including density-dependent and density-independent factors. The document also discusses r-selected and K-selected species and survivorship curves. Finally, it summarizes the processes of primary and secondary ecological succession, including examples of succession in different habitats like bare rock and wetlands.
A biofuel is a hydrocarbon that is made BY or FROM a living organism that we humans can use to power something. A thorough research work has been carried out by few of the colleagues(me & my MBA mates) to analyze the potential for the algae fuel and how can it be made commercially viable.
A bioindicator is any an "indicator species" or group of species whose function, population, or status reveal the qualitative status of the environment.
Liquid biofertilizers are suspensions having agriculturally useful microorganisms, which fix atmospheric nitrogen and solubilize insoluble phosphates and make it available for the plant.
application of biofertilizers in forest nursery. Different types of biofertilizers and application methods. advantages and disadvantages of biofertilizers.
A biofuel is a hydrocarbon that is made BY or FROM a living organism that we humans can use to power something. A thorough research work has been carried out by few of the colleagues(me & my MBA mates) to analyze the potential for the algae fuel and how can it be made commercially viable.
A bioindicator is any an "indicator species" or group of species whose function, population, or status reveal the qualitative status of the environment.
Liquid biofertilizers are suspensions having agriculturally useful microorganisms, which fix atmospheric nitrogen and solubilize insoluble phosphates and make it available for the plant.
application of biofertilizers in forest nursery. Different types of biofertilizers and application methods. advantages and disadvantages of biofertilizers.
Microbes in climate change
Biogeochemical cycle
Effects of climate on various geological regions
Terrestrial polar regions
Ocean
Fresh water
Agriculture
Soil
Factors responsible for Pollinator crisisNikita Negi
Nearly 90% of the world wild flowering species entirely or at least in part depends on animal pollination and these pollinators are at high risk due to different stressors like land fragmentation, climate change, competition for limited resources, different pathogens and pest attack, pesticide usage so it has become extremely important to initiate considerable efforts to aid pollinator conservation
Entamopathogenic Fungi as Biocontrol Agents - A Special Focus on Beauveria ba...Vigneshwaran Vellingiri
This slide is about the entomopathogenic fungus which is a fungus that can act as a parasite of insects and kills or seriously disables them. Since they are considered natural mortality agents and environmentally safe, there is worldwide interest in the use and manipulation of entomopathogenic fungi for biological control of insects and other arthropod pests.
Phytostabilization refers to establishing a plant cover on the surface of the contaminated soils, which reduces their exposure to wind, water, and direct contact with humans or animals. Phytostabilization reduces the mobility, and therefore the risk, of inorganic contaminants without necessarily removing them from the site.
Effect of climate change on crop pest interactionversha kumari
Climate change also disrupts and alters the distribution of pests and diseases, which poses a threat to agriculture. Climate change will also modify host physiology and resistance, and alter the stages and rates of the development of pests. IPM provide enough flexibility by which we will able to deal with many of the pests.
Microbes in climate change
Biogeochemical cycle
Effects of climate on various geological regions
Terrestrial polar regions
Ocean
Fresh water
Agriculture
Soil
Factors responsible for Pollinator crisisNikita Negi
Nearly 90% of the world wild flowering species entirely or at least in part depends on animal pollination and these pollinators are at high risk due to different stressors like land fragmentation, climate change, competition for limited resources, different pathogens and pest attack, pesticide usage so it has become extremely important to initiate considerable efforts to aid pollinator conservation
Entamopathogenic Fungi as Biocontrol Agents - A Special Focus on Beauveria ba...Vigneshwaran Vellingiri
This slide is about the entomopathogenic fungus which is a fungus that can act as a parasite of insects and kills or seriously disables them. Since they are considered natural mortality agents and environmentally safe, there is worldwide interest in the use and manipulation of entomopathogenic fungi for biological control of insects and other arthropod pests.
Phytostabilization refers to establishing a plant cover on the surface of the contaminated soils, which reduces their exposure to wind, water, and direct contact with humans or animals. Phytostabilization reduces the mobility, and therefore the risk, of inorganic contaminants without necessarily removing them from the site.
Effect of climate change on crop pest interactionversha kumari
Climate change also disrupts and alters the distribution of pests and diseases, which poses a threat to agriculture. Climate change will also modify host physiology and resistance, and alter the stages and rates of the development of pests. IPM provide enough flexibility by which we will able to deal with many of the pests.
This is the 7th lesson of the course - Foundation of Environmental Management taught at the Faculty of Social Sciences and Humanities, Rajarata University of Sri Lanka
This is the 7th lesson of the course 'Poverty and Environment ' taught at the Faculty of Social Sciences and Humanities, Rajarata University of Sri Lanka
I am pleased to present an outstanding Sample ESS IA that secured an impressive 28 out of 30 marks, resulting in a remarkable 7-point score. This exemplar serves as a valuable reference and resource for your ESS class, offering comprehensive insights and invaluable guidance for both students and educators alike.
Key Points:
Exceptional Achievement: The IA achieved a remarkable 28 out of 30 marks, showcasing excellence in content, research, and presentation.
7-Point Performance: Scoring a perfect 7 points in the IA demonstrates a deep understanding of Environmental Systems and Societies.
Educational Resource: This exemplary IA serves as an educational resource, providing a model for structuring, researching, and presenting ESS projects.
Invaluable Insights: Reviewing this IA will offer invaluable insights into what constitutes a high-scoring ESS IA, helping students aim for excellence.
Guidance for Students: Students can utilize this IA as a reference to enhance their own IA projects, aiming for similarly outstanding results.
Educator's Tool: Educators can use this IA to exemplify quality work to their students, facilitating better understanding of assessment expectations.
We encourage you to make the most of this exemplary ESS IA as a guiding light in your pursuit of excellence in Environmental Systems and Societies studies.
Very interesting - Can you guess what is common between all these prominent temples.
If your answer is, they all are Shiva temples, you are only partially correct.
It is actually the longitude in which these temples are located.
They all are located in 79° longitudes. What is surprising and awesome is that how the architects of these temples many hundreds of kilometers apart came up with these precise locations without GPS
K.Guru Charan Kumar, IB ESS Teacher at Pathways World School, Aravali discusses the importance of taking his IB students on field trips that enhance the learning they do in the classroom. Over the past year, K. Guru has shared numerous adventures with the IB community and we asked him to reflect on why field experience is central to his teaching.
My mission is to deliver world-class international education power point presentation through the provision of high-quality curricula, assessment and services for the IGCSE EVM.
A wide range of materials and resources is available through my Slide share to support teachers and learners in Cambridge schools. Resources suit a variety of teaching methods in different international contexts.
The content of this power point presentation is designed to encourage reflection on the limits to growth and sustainable development for IGCSE EVM.
The content of this PowerPoint is structured as a series of learning outcomes that lay out what candidates should know, understand and be able to analyze and discuss.
Environmental Management is concerned not only with the impact of humankind on the planet but also with the patterns of human behavior necessary to preserve and manage the environment in a self-sustaining way. Study is linked to the areas of new thinking in environmental management, environmental economics and the quest for alternative technologies. Classroom studies and optional coursework allow candidates to obtain a local as well as a global perspective.
My mission is to deliver world-class international education power point presentation through the provision of high-quality curricula, assessment and services for the IGCSE EVM.
A wide range of materials and resources is available through my Slide share to support teachers and learners in Cambridge schools. Resources suit a variety of teaching methods in different international contexts.
The content of this power point presentation is designed to encourage reflection on the limits to growth and sustainable development for IGCSE EVM.
The content of this PowerPoint is structured as a series of learning outcomes that lay out what candidates should know, understand and be able to analyze and discuss.
Environmental Management is concerned not only with the impact of humankind on the planet but also with the patterns of human behavior necessary to preserve and manage the environment in a self-sustaining way. Study is linked to the areas of new thinking in environmental management, environmental economics and the quest for alternative technologies. Classroom studies and optional coursework allow candidates to obtain a local as well as a global perspective.
My mission is to deliver world-class international education power point presentation through the provision of high-quality curricula, assessment and services for the IGCSE EVM.
A wide range of materials and resources is available through my Slide share to support teachers and learners in Cambridge schools. Resources suit a variety of teaching methods in different international contexts.
The content of this power point presentation is designed to encourage reflection on the limits to growth and sustainable development for IGCSE EVM.
The content of this PowerPoint is structured as a series of learning outcomes that lay out what candidates should know, understand and be able to analyze and discuss.
Environmental Management is concerned not only with the impact of humankind on the planet but also with the patterns of human behavior necessary to preserve and manage the environment in a self-sustaining way. Study is linked to the areas of new thinking in environmental management, environmental economics and the quest for alternative technologies. Classroom studies and optional coursework allow candidates to obtain a local as well as a global perspective.
As part of the IB philosophy, one must understand that not everything can be taught within the classroom. Thus, field trips provide the perfect opportunity to apply ourselves fruitfully. Laden with their luggage, and appetite for knowledge, the group of ESS and Geography students readied themselves for the learning expedition to Sundarbans, West Bengal.
The most engaging component of ESS & Geo IBDP is the coursework/fieldwork which culminates in an Analytical report based on Primary Data which the students gather and work upon. In this context we are all set to embark on our journey to Sundarbans Delta (UNESCO World Heritage site) which is located in Kolkata. This year 41 IBDP students with 4 teachers ventured for the very first time in the country to visit the Sundarbans(Kolkata) for the field trip.
The IBDP ESS & Geography students studied “Ecological Footprints of Eco tourism & Environmental Sustainability, Quality and Patterns of Resource Consumption” with special reference to Mangrove forest of Sundarbans, West Bengal.
Farmers from Maldevta Village, who work in the lowest sector of the economy, have minimal land and resources to help them grow crops. This obligates them to enter the hills with their cattle to allow grazing. Farmers also clear some forest areas, to increase their farm land for more income, thus reducing the biodiversity. As a result of the reduced in forest area and resources, wild animals invade villages and destroy farmlands. In some cases, because of minimal knowledge of the chemical Pesticides, it’s overuse affects not only the farmland, but also nearby water resources as it leads to eutrophication. This relates to my RQ because after surveying the villagers and collecting the raw data from the Simpson’s Diversity index it allowed me to evaluate the effect of human intervention on the natural environment and thus evaluating the effect of Ecological Footprint.
This IA talks about research is to compare Simpson Diversity of four areas of Mahendrapur village based on the amount of sunlight received and the amount of nutrients found near the place where they are located (near the water body or away from the water body).
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
1. 2.6 – Changes and some 2.5 Function
2.6.1 - 2.6.4
And 2.5.5 and 2.5.6
5/11/2013
IB/ESS
Author-Guru
Topic 2 – The
Ecosystem
1
2. Specifications
IB/ESS
Author-Guru
2.6.2 – Describe and explain ‘S’ and ‘J’ population growth curves.
Population curves should be sketched, described, interpreted
and constructed from given data.
5/11/2013
2.6.1 – Explain the concepts of limiting factors and carrying
capacity in the context of population growth.
2
3. Population Growth
IB/ESS
Author-Guru
• Nearly 1.6 million people
join the human population
each week.
• 84 million people join every
year.
• In three years the human
population grows by an
amount nearly equivalent to
the entire U.S population.
• By 2025 the world
population could exceed 8
billion
5/11/2013
Some Facts
3
4. • We are going to concentrate on population
control of ecosystems but these theories can
also be applied to human populations.
IB/ESS
• Studies on both human populations and smaller
ecosystem populations are carried out in depth.
Author-Guru
• The study of any population is an important
aspect of science.
5/11/2013
Population Studies
4
5. • The factors affecting a population
size may be biotic or abiotic.
IB/ESS
Author-Guru
• By taking samples and counting the
numbers of organisms in a
particular habitat, ecologists can
study the affects of any factor on
the size of a population.
5/11/2013
Population Size
• Together they affect the rate at
which population grows, and also
it’s final size.
5
6. IB/ESS
• How many abiotic factors can you think of that might affect
population size?
Author-Guru
• How many biotic factors can you think of that might affect
population size?
5/11/2013
Biotic Factors Affecting Population Size
6
7. Biotic and Abiotic Factors
5/11/2013
1. Temperature – higher
temperatures speed up
enzyme-catalyzed
reactions and increase
growth.
2. Oxygen Availability – affect
the rate of energy
production by respiration.
3. Light Availability – for
photosynthesis and
breeding cycles in animals
and plants.
4. Toxins and pollutants –
tissue growth may be
reduced.
IB/ESS
1. Food – both quantity
and quality of food are
important.
2. Predators – refer back
to predator prey
relationships.
3. Competitors – other
organisms may require
the same resources
from an environment.
4. Parasites – may cause
disease and slow down
the growth of an
organism.
Abiotic
Author-Guru
Biotic
7
10. • Look at the graph of population growth.
• This shows how population growth is eventually
inhibited by environmental resistance and the
environment reaches it’s carrying capacity.
IB/ESS
• This is usually because there is plenty of food and no
accumulation of poisonous wastes.
Author-Guru
• When a small population grows in a particular
environment, the environmental resistance is almost
non-existent.
5/11/2013
Carrying Capacity
10
11. • Think of your brine shrimps!?
IB/ESS
• Once the carrying capacity is reached, unless the
environmental resistance is changed, e.g. by a
new disease, the size of the population will only
fluctuate slightly.
Author-Guru
• The carrying capacity (K) is the maximum
number of a species that the habitat can hold.
5/11/2013
Carrying Capacity
11
12. ‘S’ Curves
IB/ESS
Author-Guru
• This is the type of graph that is almost always seen in nature.
• As the energy resources become more scarce the population
size levels off at the carrying capacity (K).
5/11/2013
• The graph we have just been looking at is an example of an ‘S’
curve.
12
14. • If the resources of the new habitat were endless
then the population would continue to increase
at this rate.
IB/ESS
• This type of growth produces a J shaped growth
curve.
Author-Guru
• Just as in the ‘S’ curve example, a population
establishing themselves in a new area will
undergo rapid exponential growth.
5/11/2013
‘J’ Curves
14
15. • Can you think of any examples where ‘J’ curve
population growth would be extremely
desirable.
IB/ESS
• Initially exponential growth will occur but
eventually the increase in numbers will not be
supported by the environment.
Author-Guru
• This type of population growth is rarely seen in
nature.
5/11/2013
‘J’ Curves
15
16. • It is very natural to ask the linked questions - does humanity
have a carrying capacity and, if so, what is it - and when will
we reach or overshoot this
IB/ESS
• Furthermore, experience with other species tells us that,
ultimately, resource limitations and/or habitat degradation
will force the human population curves to approach an upper
limit - the carrying capacity, often symbolized as " K" by
ecologists.
Author-Guru
• ‘As we have seen, the human population growth curve is
currently following an exponential curve or a "J-shape”.
Common sense tells us that such growth cannot continue otherwise within a few hundred years every square foot of
the Earth's surface would be taken up by a human.
5/11/2013
Is there a Carrying Capacity for Homo
sapiens?
16
17. Activity
IB/ESS
Author-Guru
2.6.3 – Describe the role of density-dependent and densityindependent factors, and internal and external factors, in the
regulation of populations.
5/11/2013
• Complete the activity – The new zoos
17
18. • These factors exert their effect irrespective of
the size of the population when the catastrophe
struck.
IB/ESS
Author-Guru
• The following factors are classed as densityindependent factors:
• Drought
• Freezes
• Hurricanes
• Floods
• Forest Fires
5/11/2013
Density Independent Factors
18
19. The drought ended in 1978, but even
with ample food once again available
the finch population recovered only
slowly.
IB/ESS
The decline (from 1400 to 200
individuals) occurred because of a
severe drought that reduced the
quantity of seeds on which this
species feeds.
Author-Guru
This graph shows the decline in the
population of one of Darwin's finches
(Geospiza fortis) on Daphne Major, a
tiny (100-acre) member of the
Galapagos Islands.
5/11/2013
Density Independent Factors
19
20. • Many rodent populations (e.g.,
lemmings in the Arctic) also go
through such boom-and-bust
cycles.
IB/ESS
• Read the information about the
gypsy moth.
Author-Guru
• Intraspecific Competition competition between members of
the same species.
5/11/2013
Density Dependant Factors
20
21. • This occurs when two species share overlapping
ecological niches, they may be forced into
competition for the resource(s) of that niche.
IB/ESS
• This can include food, nesting sites, sunlight.
Author-Guru
• Interspecific Competition – this is competition
between different species for different
resources.
5/11/2013
Density Dependant Factors
21
23. • Ragweed is well adapted to
exploiting it’s environment
in a hurry – before
competitors can become
established!
IB/ESS
Author-Guru
• “I once ploughed up an old
field and allowed it to lie
fallow. In the first season it
grew a large crop of
ragweed.”
5/11/2013
R-Strategists
23
24. R-Strategists
• Can you think of any other animals that may be r-strategists?
IB/ESS
Author-Guru
• We say that they have a high value of ‘r’
• They are called r-strategists
5/11/2013
• Ragweed’s approach to continued survival is through rapid
reproduction.
24
25. 2.
3.
4.
5.
6.
7.
IB/ESS
1.
In general, r-strategists share a number of
features:
Usually found in disturbed and/or transitory
habitats
Have short life spans
Begin breeding early in life
Have short gestation times
Produce large numbers of offspring
Take little care of their offspring (infant
mortality large)
Have efficient means of dispersal to new
habitats
Author-Guru
•
5/11/2013
R-Strategists
25
26. • K-strategists have a stable population that is
close to K.
• There is nothing to be gained from a high r.
• The species will benefit the most by a close
adaptation to the conditions of the environment.
IB/ESS
Author-Guru
• When a habitat become filled with a diverse
collection of creatures competing with one
another for resources, the advantage shifts to KStrategists
5/11/2013
K-Strategists
26
27. IB/ESS
K-strategists share these qualities:
Found in a stable habitat
Long life spans
Begin breeding later in life
Long gestation times
Produce small numbers of offspring
Take good care of their young – infant
mortality low
7. Have evolved to become increasingly efficient
at exploiting an ever-narrower slice of their
environment.
Author-Guru
•
1.
2.
3.
4.
5.
6.
5/11/2013
K-Strategists
27
29. Survivorship Curves
IB/ESS
Author-Guru
• Curve B – typical of populations in which factors such
as starvation and disease inhibit the effects of aging
and infant mortality is high.
5/11/2013
• Curve A – characteristic of organisms that have low
mortality until late in life when aging takes its toll.
• Curve C – a theoretical curve for an organism whereby
the chance of death is equal at all stages
• Curve D – typical of organisms that produce huge
numbers of offspring accompanied by high rates of
mortality.
29
30. Survivorship Curves
• The Californian side-blotted lizard
Author-Guru
IB/ESS
• R-strategists usually have D survivorship curves.
5/11/2013
• K-strategists usually have survivorship curves somewhere
between A and C.
30
31. • 2.6.7 – Describe factors affecting the nature of
climax communities.
IB/ESS
• 2.6.6 – Explain the changes in energy flows,
gross and net productivity, diversity and mineral
cycling in different stages of succession.
Author-Guru
• 2.6.5 – Describe the concept and processes of
succession in a named habitat.
5/11/2013
Specifications
31
32. Succession – An intro
• Succession takes places as a result of complex
interactions of biotic and abiotic factors.
• Early communities modify the physical environment
causing it to change.
• This in turn alters the biotic community which
further alters the physical environment and so on.
IB/ESS
Author-Guru
• A forest following a disturbance such as a fire.
5/11/2013
• The gradual process by which the species population
of a community changes is called ecological
succession.
32
33. Succession – What happens?
IB/ESS
Author-Guru
• A succession (or sere) proceeds in seral stages, until the
formation of a climax community is reached.
5/11/2013
• Each successive community makes the environment more
favourable for the establishment of new species.
33
34. Primary Succession
IB/ESS
• You will be studying glacial moraines in detail as well as the
succession occurring on bare rock.
Author-Guru
• Can you think of examples where this would occur?
5/11/2013
• Refers to colonization of regions where there is no pre-existing
community.
34
35. Succession
IB/ESS
Author-Guru
• Study the information on glacial moraines and answer the
following questions:
5/11/2013
• Community changes on a glacial moraines
35
36. 1.
2.
Explain what is meant by a climax community.
Explain each of the following changes which occur
during succession:
Species diversity increases
Gross production increases
Stability of the ecosystem increases
Give two reasons why farmland in the UK does not
reach a climax community.
a)
b)
c)
3.
IB/ESS
During succession there is a change in species
composition of a community. There are also changes
in species diversity, stability of the ecosystem, and in
gross and net production until a climax community is
reached.
Author-Guru
•
5/11/2013
Questions – Glacial Moraines
36
37. IB/ESS
• Secondary Succession – occurs on sites that have previously
supported a community of some sort.
• Examples?
Author-Guru
• Primary Succession – occurs on newly formed habitats that
have not previously supported a community.
• Examples?
5/11/2013
Primary and Secondary Succession
37
38. Lichens,
bryophytes
and annual
herbs
After 100-200 years
Slower growing
broadleaf species
e.g. oak
Complex Community
Fast
growing
trees e.g.
Ash
Author-Guru
IB/ESS
Bare Rock
Mosses,
Grasses and
small
shrubs
5/11/2013
Primary Succession – Bare
Rock
38
Example for a Northern Hemisphere lithosere: a succession on bare rock
39. • As these species begin to grow well, they produce shade.
Their own seedlings grow more poorly than shade-adapted
plants.
• Plants that grow well under full sun are replaced by plants
that germinate and grow better in deeper shade.
IB/ESS
• Examples = lichens, grasses, herbs
Author-Guru
• These are usually fast growing plants that photosynthesize
well in full sunlight.
• We call these pioneer species making up the pioneer
community
5/11/2013
In Summary - the 1st Invaders!
39
40. Secondary Succession
• Humans may deflect the natural course of succession
in these circumstances (e.g. by mowing or farming).
• This leads to the development of a different climax
community than would otherwise develop naturally.
IB/ESS
Author-Guru
• These events do not involve loss of the soil.
• Secondary succession therefore occurs more rapidly
than primary succession.
5/11/2013
• This type of succession takes place after a land
clearance (e.g. from fire or landslide).
40
41. 1-2
3-5
Young broad
leaved woodland
31-150
Mature
woodland:
mainly oak
Scrub: shrubs
and small trees
IB/ESS
Time to develop: Years
Grasses and low
growing
perennials
Author-Guru
Primary Bare
Earth
Open pioneer
community
(annual grasses)
5/11/2013
Secondary Succession – Cleared
Land
16-30
41
150+ = climax community
42. Succession Continues
• Animal species have a profound affect on the plant species
occurring within a habitat.
• Changing conditions in the present community allows for new
species to become established (the future community).
• Succession continues until the climax community is reached.
IB/ESS
Author-Guru
• Decomposers will join the community as well as animal
species.
5/11/2013
• As the plant community changes, the soil will also undergo
changes (abiotic factors will change).
42
43. Wetland Succession
5/11/2013
• Wetland areas present a special case of ecological succession.
Open water
Plant invasion
Siltation and
Infilling
Author-Guru
IB/ESS
• Wetlands are constantly changing:
• Wetland ecosystem may develop in a variety of ways:
43
44. Wetland Succession
• In special circumstances, a an acid peat bog may develop.
(may take 5000+ years).
IB/ESS
Author-Guru
• In non-acidic, poorly drained areas, a swamp will eventually
develop into a fen.
5/11/2013
• In well drained areas, pasture or heath may develop as a
result of succession from fresh water to dry land.
44
45. IB/ESS
• This is called productivity
Author-Guru
• Think back to the work on food webs/chains
• It is often useful to know how much energy is
passing through a trophic level over a period of
time.
5/11/2013
Productivity
• Productivity is a measure of the amount of
energy incorporated into the organisms in a
trophic level, in an area, over a certain period of
time.
45
46. IB/ESS
• 2.5.6 – Define and Calculate the values of gross and net
productivity from given data
Author-Guru
• 2.5.5 – Define the terms gross productivity, net productivity,
primary productivity, secondary productivity, gross primary
productivity and net primary productivity.
5/11/2013
Specifications
46
47. Productivity
• The rate at which producers convert light energy into chemical
energy is called primary productivity.
IB/ESS
Author-Guru
• It is therefore measured in units of kilojoules per square metre
per year (kJm-2year-1)
5/11/2013
• The area is normally one square metre and the time is usually
one year.
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48. Gross Productivity
• The producers use some of this energy during respiration and
energy needs which is eventually lost to the environment as
heat.
• The remaining energy is available to the herbivores and is
known as net primary productivity (NPP)
IB/ESS
• It is related to the total amount of chemical energy
incorporated into the producers.
Author-Guru
• This is sometimes shown as GPP – Gross Primary Productivity
5/11/2013
• Gross Productivity (GP) – is the total gain in energy or
biomass per unit time.
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49. Recap of Definitions!
• Gross Productivity (GP) = the total gain in energy/biomass per unit time.
• Gross Primary Productivity (GPP) = the total gain in energy of the producers.
• Net Productivity (NP) = the gain in energy/biomass per unit time remaining
after allowing for respiration (R) loses.
• Net Primary Productivity (NPP) = the gain in energy/biomass per unit time
remaining after allowing for respiration loses which is passed onto the
herbivores.
IB/ESS
• Secondary Productivity = The rate at which primary material is synthesised
into animal tissue per unit area in a given time.
Author-Guru
• Primary Productivity = The rate at which energy/biomass is formed through
photosynthesis
5/11/2013
• Productivity = production per unit time
49
50. IB/ESS
• The rate at which plants can convert light energy
into chemical energy is affected by many factors:
• Sunlight
• Water
• Temperature
• Amount of nutrients
Author-Guru
• Primary productivity varies greatly in different
environments.
5/11/2013
Environmental Productivity
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51. Environmental Productivity
• In the oceans however, the most productive areas are in cold
regions due to the up-welling of water bringing plant nutrients
with it.
IB/ESS
Author-Guru
• This is due to good light levels and high temperatures in the
tropics.
5/11/2013
• In natural ecosystems primary productivity tends to be highest
in tropical regions.
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52. IB/ESS
• We can calculate NPP for both producers and
consumers as:
NPP = GPP – energy used in respiration
Author-Guru
• We can calculate GPP as follows:
GPP = NPP + R
5/11/2013
Important Calculations
• In addition, the equation for consumers only is:
GP = food eaten – faecal losses
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53. Calculating Productivity Values
• What is the GPP of an ecosystem if the NPP is 1660 kJm2yr-1 and the energy lost during respiration is 573 kJm-2yr1?
• What is the NPP if the GPP is 2700 kJm-2yr-1 and the
energy used in respiration is 1850 kJm-2yr-1?
IB/ESS
Author-Guru
• What is the % energy from sunlight that is fixed as GPP if
the total energy from the sun in 3 x 106 and the gross
primary productivity = 2.8 x 104?
5/11/2013
• Some easy ones to start you off!
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55. Therefore, for photoautotrophs, photosynthetic
efficiency is determined as:
Photosynthetic Efficiency =
Net production ÷ Light Energy Absorbed
IB/ESS
Ecological Efficiency is the net production of new
biomass at each trophic level as a percentage of the
total energy flowing through that trophic level
Author-Guru
Energy flow diagrams illustrate energy flow
through communities and include values for
respiratory losses and energy flow through
the decomposers
Information from energy flow diagrams can be used to
calculate ecological efficiencies
5/11/2013
Energy Flow Diagrams
55
56. 5/11/2013
IB/ESS
Author-Guru
Use information from the energy flow diagram to:
• Explain the meaning of the term Gross Primary Production
• Explain the meaning of the term Net Primary Production
• Calculate the Photosynthetic Efficiency of the phytoplankton
56
57. 5/11/2013
IB/ESS
Author-Guru
Gross Primary Production is the total energy fixed
by photoautotrophs during photosynthesis
Net Primary Production is the energy stored as
biomass (gross production – energy lost as heat
in respiration)
Photosynthetic
Efficiency =
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3.7 x 104
------------ x 100
172 x 104
= 2.15%
60. • This is because climax communities are better
adapted to an efficient rate of utilisation of their
resources.
• They become stable.
IB/ESS
• As ecosystems become more diverse, the overall
GPP is also going to increase.
Author-Guru
• The NPP and GPP of any ecosystem is going to
fluctuate. This is especially the case during each
seral stage.
5/11/2013
Finally Back To Succession!
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61. The Early Stages
• This is due to low respiration rates of the initial
producers and therefore a lot of energy available to be
passed on.
• This allows the system to grow and biomass to
accumulate.
IB/ESS
• Net Productivity = High
Author-Guru
• This is due to the initial conditions and the relatively low
density of producers.
5/11/2013
• Gross Productivity = Low
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62. The Later Stages
• Net Productivity = Low
• Increased rates of respiration and other energy
sapping activities by consumers means that NP
will begin approaching zero.
IB/ESS
Author-Guru
• This is due to an increase in the consumer
community who can synthesise a lot of energy
from the food they eat.
5/11/2013
• Gross Productivity = High
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63. • Ultimately, the climate will be responsible for
affecting the nature of the climax community
unless human or other factors maintain an
equilibrium at a sub-climax community.
IB/ESS
• Climax communities are more stable that the
seral stages that preceded them.
Author-Guru
• Succession comes to an end with the
establishment of a mature, relatively stable
community – the climax
5/11/2013
The Climax
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