Ecology.

Slides:



Advertisements
Similar presentations
Population Dynamics.
Advertisements

HUMAN POPULATION DYNAMICS
Population Ecology.
Part 6. Biodiversity and Conservation
Part 6. Biodiversity and Conservation
Chapter 4 Notes, Population Ecology
Interactions in an Ecosystem
Lecture 16 Population Dynamics Ozgur Unal
Chapter 14 Interactions in an Ecosystem. Animals and Their Habitats.
All living organisms are limited by factors in the environment.
Biodiversity Day 6. What is Biodiversity? The variety of life in an area that is determined by the number of different species in that area. There are.
Population Dynamics – Growth Rates Chapter 4. Learning Targets I can… 1. Explain the concept of carrying capacity 2. Model how limiting factors and organism.
Population Dynamics Day 4
Population Ecology. Population Characteristics Population Density: –The number of organisms per unit area Spatial Distribution: –Dispersion: The pattern.
Ecology.
Examining Population Density and Dispersion The following image shows a world map of human population density. Discuss with your group, the patterns that.
3.1 Community Ecology.
How populations grow Chapter 14 – Notesheet II 14-3 – population density & distribution 14-4 – population growth curves.
Population density - number of individuals that live in a defined area.
Ecology of Populations
Population. 1.What are the characteristics of population? 2. population density – number of organisms per unit area 2. dispersion – the pattern of spacing.
Populations are described by density, spatial distribution, and growth rate. Population Ecology.
6/8/2016SB4d1 ECOLOGY Population Growth. SB4D Students will assess the dependence of all organisms on one another and the flow of energy and matter within.
Population Dynamics Part 2. Population Characteristics 1.Population Density: – The number of organisms per unit area 2.Spatial Distribution: – Dispersion:
Biology Chapter 14: Interactions in Ecosystems
Population Ecology.
Theme “A population and its sustainability”
Ecological Succession
Population Dynamics Biology I.
The Biology of Populations
Population Dynamics Unit 1: Ecology
Chapter 4.1 Population Ecology. Chapter 4.1 Population Ecology.
Section 19-1 & 19-2 Populations
Ch 5 Populations Students know how to analyze changes in an ecosystem resulting from changes in climate, human activity, introduction of nonnative species,
Section 1: Population Dynamics
May 2017 Journal:.
Population Ecology.
Population Dynamics Chapter 4 Section 1.
Population Characteristics
Ecology Section two notes
Chapter 4 Population Ecology
Interactions in Ecosystems
Population Ecology Chapter 4.
Population Biology Chapter 4.
Ecological Organization
Population and Community Ecology
Population Dynamics Chapter 4 Section 1.
Populations.
14.3 Population Density and Dist.
Population Growth.
Ecology: Everything Else 
Ecology Examine factors such as carrying capacity, fecundity, density and predation that can cause fluctuations in populations. Determine through computer.
Part 6. Biodiversity and Conservation
#26 Population dynamics.
Energy Transfer in an Ecosystem
Population density - number of individuals that live in a defined area.
Population Ecology Items that are BOLD, underlined, or a different color are MOST important to write down.
Population Ecology.
Changes in Ecosystems: Ecological Succession
14.3 Population Dynamics.
Population Ecology.
May 9, 2018 Journal: Draw a food chain with four organisms.
Population Dynamics Unit 4: The Biosphere
Populations, Communities and Biodiversity
Feb 16, 2011 Bring up your Invasive Species Analysis questions
Community Ecology Chapter 3.
VII. Community; interacting populations that
Biodiversity, Species Interactions, and Population Control
The Biology of Populations
Populations Biodiversity and Conservation
Presentation transcript:

Ecology

Population Characteristics Population Ecology: Population Characteristics Population Characteristics Population Density: The number of organisms per unit area Spatial Distribution: Dispersion: The pattern of spacing a population within an area 3 main types of dispersion Clumped Uniform Random The primary cause of dispersion is resource availability

Population Limiting Factors Population Ecology: Population Characteristics Population Limiting Factors Population growth rate How fast a given population grows Factors that influence this are: Natality (birth rate) Mortality (death rate) Emigration (the number of individuals moving away from a population) Immigration (the number of individuals moving into a population)

Population Limiting Factors Population Ecology: Density-independent factors Population Limiting Factors Density-independent factors Factors that limit population size, regardless of population density. These are usually abiotic factors They include natural phenomena, such as weather events Drought, flooding, extreme heat or cold, tornadoes, hurricanes, fires, etc

Population Limiting Factors Population Ecology: Density-dependent factors Population Limiting Factors Density-dependent factors Any factor in the environment that depends on the number of members in a population per unit area Usually biotic factors These include Predation Disease Parasites Competition

Understanding Exponentials Population Ecology: Population Growth Rate Understanding Exponentials Put your pens down for a minute & think about this: An employer offers you two equal jobs for one hour each day for fourteen days. The first pays $10 an hour. The second pays only 1 cent a day, but the rate doubles each day. Which job will you accept? 6

Understanding Exponentials Population Ecology: Population Growth Rate Understanding Exponentials Now, how much would your employer owe you if you stayed at this job for another 2 weeks? Job 2 lags for a long time before exponential growth kicks in! What would happen if this type of growth took place within a population?

Population Limiting Factor Population Ecology: Population Growth Rate Population Limiting Factor Population growth models Exponential growth model Also called geometric growth or J-shaped growth. First growth phase is slow and called the lag phase Second growth phase is rapid and called the exponential growth phase Bacteria can grow at this rate, so why aren’t we up to our ears in bacterial cells?

Population Limiting Factors Population Ecology: Population Growth Rate Population Limiting Factors Population growth models Limits to exponential growth Population Density (the number of individuals per unit of land area or water volume) increases as well Competition follows as nutrients and resources are used up The limit to population size that a particular environment can support is called carrying capacity (k)

What population do you think this is? Population Ecology: Population Growth Rate What population do you think this is?

So, what do you think is going to happen to the human population? We will probably reach our carrying capacity. Our growth rate will start to look like most organisms, which is the Logistic Growth Model Carrying Capacity (k) What letter does this curve kind of look like?

Population Limiting Factors Population Ecology: Population Growth Models Population Limiting Factors Population growth models Logistic Growth Model Often called the S-shaped growth curve Occurs when a population’s growth slows or stops following exponential growth. Growth stops at the population’s carrying capacity Populations stop increasing when: Birth rate is less than death rate (Birth rate < Death rate) Emigration exceeds Immigration (Emigration > Immigration)

Population Limiting Factors Population Ecology: Population Growth Models Population Limiting Factors Population growth models Logistic Growth Model The S-curve is not as pretty as the image looks Carrying capacity can be raised or lowered. How? Example 1: Artificial fertilizers have raised k Example 2: Decreased habitat can lower k Populations don’t reach k as smoothly as in the logistic graph. Boom-and-Bust Cycles Predator-Prey Cycles

Community Ecology: Communities Review: A community is a group of interacting populations that occupy the same area at the same time.

Communities Limiting Factors Community Ecology: Communities Communities Limiting Factors Any abiotic or biotic factor that restricts the numbers, reproduction, or distribution of organisms.

Communities Range of Tolerance Community Ecology: Communities Communities Range of Tolerance The limits within which an organism can exist.

Ecological Succession Community Ecology: Ecological Succession Ecological Succession Ecological Succession The change in an ecosystem that happens when one community replaces another as a result of changing biotic and abiotic factors

Ecological Succession Community Ecology: Ecological Succession Ecological Succession Ecological Succession Consists of 2 types: Primary Succession Secondary Succession

Ecological Succession Community Ecology: Ecological Succession Ecological Succession Ecological Succession: Primary The establishment of a community in an area of exposed rock that does not have topsoil is called Primary Succession. It occurs very slowly at first

Ecological Succession Community Ecology: Ecological Succession Ecological Succession Ecological Succession: Primary The first organisms to arrive are usually lichens or mosses, which are called pioneer species. They secrete acids that can break down rock Their dead, decaying organic materials, along with bits of sediment from the rock make up soil.

Ecological Succession Community Ecology: Ecological Succession: Primary Succession Ecological Succession Ecological Succession: Primary Small weedy plants and other organisms become established. As these organisms die, additional soil is created

Ecological Succession Community Ecology: Ecological Succession: Primary Succession Ecological Succession Ecological Succession: Primary Seeds brought in by animals, water and wind begin to grow in the soil. Eventually enough soil is present for shrubs and trees to grow.

Ecological Succession Community Ecology: Ecological Succession: Primary Succession Ecological Succession Ecological Succession: Primary The stable, mature community that eventually develops from bare rock is called a climax community.

Ecological Succession Community Ecology: Ecological Succession: Primary Succession Ecological Succession Ecological Succession: Secondary Disturbances (fire, flood, windstorms) can disrupt a community. After a disturbance, new species of plants and animals might occupy the habitat.

Ecological Succession Community Ecology: Ecological Succession: Secondary Succession Ecological Succession Ecological Succession: Secondary Pioneer species in secondary succession are usually plants that begin to grow in the disturbed area. This is much faster than primary succession

Ecological Succession Community Ecology: Ecological Succession Ecological Succession Ecological Succession: End point? Cannot be predicted Different rates of growth & human involvement make it impossible to know if a true climax community has been reached.

Biodiversity What is Biodiversity? Biodiversity and Conservation: What is biodiversity? Biodiversity What is Biodiversity? The variety of life in an area that is determined by the number of different species in that area. There are 2 main types: Genetic Diversity Species Diversity

Biodiversity and Conservation: Why is biodiversity important? Penicillin: Derived from bread mold The teosinte plant contains genes that are resistant to several viral diseases that affect domesticated corn plants. These genes have been used to produce viral-resistant domestic corn varieties. Teosinte: A distant relative of corn Domestic corn plant Madagascar Periwinkle: Used to treat childhood forms of leukemia

Biodiversity and Conservation: Extinctions Extinction Rates The gradual process of becoming extinct is known as background extinction. Mass extinctions: When a large percentage of all living species become extinct in a relatively short period of time. 250 MYA: Over 90% of species died

Estimated number of Extinctions since 1600 Biodiversity and Conservation: Extinctions Estimated number of Extinctions since 1600 Group Main-land Island Ocean Total Approximate Number of Species Percent of Group Extinct Mammals 30 51 4 85 4000 2.1 Birds 21 92 113 9000 1.3 Reptiles 1 20 6300 0.3 Amphibians 2 4200 0.05 Fish 22 23 19,100 0.1 Invertebrates 49 48 98 1,000,000+ 0.01 Flowering Plants 245 139 384 250,000 0.2 Since the mid-1970s there has been an alarming decrease of amphibian populations, and many are on the verge of extinction.

Five Most Recent Mass Extinctions Biodiversity and Conservation: Extinctions Five Most Recent Mass Extinctions Cretaceous Period (65 MYA) Triassic Period (200 MYA) Permian Period (250 MYA) Devonian Period (360 MYA) Ordovician Period (444 MYA)