Interdependence of Living Things The Biosphere Ecosystems and

Interdependence of Living Things ØThe Biosphere ØEcosystems and Communities ØPopulations ØHumans in the Biosphere

The Biosphere

What is ecology? Ø Ecology – study of interactions among and between organisms and their environment Ø Biosphere – contains the combined portions of the earth in which all life exists l 8 km above Earth’s surface 11 km below the ocean surface Ø Levels of organization: l Individual population community ecosystem Biome Biosphere

Energy flow Ø Producers l l l Ø Main form of energy on Earth = sunlight Capture energy from sunlight (photosynthesis) or from chemical energy (chemosynthesis) = producers Autotrophs = capture energy from sunlight to make food (photosynthesis) Consumers l Rely on other organisms for energy and food (cellular respiration) = “heterotrophs” or “consumers”

Feeding Relationships Energy flows from producers to various heterotrophs Ø Food chain Ø l Ø Food web l Ø Energy is transferred by eating and being eaten Links all the food chains in an ecosystem together Trophic level l l Each step in a food chain or web Producers are the first trophic level Consumers make up the 2 nd, 3 rd, or higher levels Each consumer depends on the level below for energy

Energy Pyramid Only 10% of the energy available within one tropic level is transferred to the next Ø The rest of the energy is used during cellular processes and escapes as heat!!! Ø

Biomass Pyramid Total amount of living tissue within each trophic level Ø grams of organic matter/ unit area Ø Potential food for each level Ø

Pyramid of Numbers Ø Number of individuals at each trophic level

Toxins that do not follow the flow of energy model Bioaccumulation • This happens when a top predator consumes organisms that have a small amount of toxin in their bodies, but over time, that toxin builds up to harmful levels in the top predator. Biomagnification • This happens when an organism has a small amount of toxin in its system and when consumed, it passes all of that toxin to the next organism. • The cycle continues up the food chain.

Recycling in the Biosphere Ø Matter is recycled within and between ecosystems Ø Matter is not used up…it is transformed!!! Ø Matter is recyled through biogeochemical cycles: l l Water cycle Nutrient cycles (carbon, nitrogen, phosphorus)

The Water Cycle Ø Liquid gas (evaporation) Ø Evaporation from plants = transpiration Ø Water is recycled through the Biopshere Ø 1 water molecule 4000 years to complete one cycle

Nutrient Cycles Ø Living things need nutrients to grow and carry out essential life functions. Ø Nutrients are often in short supply in an ecosystem Ø Recycling nutrients is vital to ecosystem health Ø Prevents toxic concentrations of chemicals

Ecosystems and Communities

The Role of Climate Weather day-to-day local condition of Earth’s atmosphere Ø Climate average, year-after-year condition of temperature and precipitation in a particular region Ø l l Factors include: trapping of heat by the atmosphere, the latitude, the transport of heat by winds and ocean currents, the amount of precipitation that results, the shape and elevation of landmasses Energy of sunlight is the ultimate driver of climate

Biomes Ø Each biome is defined by a unique set of: 1. 2. abiotic factors (particularly climate) a characteristic ecological community

Climatograms Ø Create a climatogram using data from South Kingstown RI l What biome do we belong to? Ø Compare our climatogram to the Biome you have been working with. l Prompt: Compare the climatogram for South Kingstown (temperate forest biome) to the Biome you have been studying. How are they similar? How are they different? Use specific evidence to support your response.

The Greenhouse Effect Ø Carbon dioxide, methane, water vapor, and other gases l l Trap heat energy Maintains Earth’s temperature range

Effect of Latitude on Climate Ø The Earth is tilted on its axis! l Ø Solar radiation strikes different regions of the Earth’s surface at an angle THUS, Earth has 3 main climate zones: l l l Polar zone very low angle (cold areas – 66. 5° – 90° N and S) Temperate zone angle changes over the year (warm and cold areas – 23. 5° – 66. 5° N and S) Tropical zone nearly direct angle (always warm - 0° - 23. 5° N and S)

Heat Transport in the Biosphere Ø Unequal heating of Earth’s surface drives winds and ocean currents l Ø Wind currents l l Ø Warm air rises, cool air sinks The prevailing (global) winds affects the climate in a given region Ocean currents l l Ø Transport heat throughout the biosphere Warm water rises, cool water sinks The global ocean currents affects the climate of nearby landmasses Landmasses l l Mountain ranges can interfere with air mass movement Rain shadow effect one side is wet and the other dry

Biotic and Abiotic Factors that Shapes Ecosystems Ø Biotic Factors l l Ø Abiotic Factors l l Ø Biological influences on organisms within an ecosystem Includes the entire living cast of characters with which an organism might interact Physical or nonliving influences that shape ecosystems Includes: temperature, precipitation, humidity, wind, nutrient availability, soil type, sunlight TOGETHER (Biotic and Abiotic factors) “Habitat” of an organism

The Niche Ø The full range of biotic and abiotic conditions in which an organism lives and uses those conditions. l Example: It’s place in the food web, the range of temperatures needed for survival, etc. Ø No 2 species can share the same niche!!!

Community Interactions Ø Organisms interact constantly ecosystems Ø 3 main types = l l l Competition Predation Symbiosis • • • Mutualism Commensalism Parasitism shapes

Competition Ø Occurs when a resource is being used at the same time in the same place. Ø Resource = any necessity of life (water, nutrients, light, food, or space) Ø Often results in a winner and a loser. Ø Competitive Exclusion Principle: l No 2 species can occupy the same niche in the same habitat at the same time.

Predation Interaction where one organism captures and feeds on another organism Ø Predator = one that does the killing Ø Prey = one that is being eaten Ø

Symbiosis Any relationship in which 2 species live closely together (3 main types) Ø Mutualism: Ø l l Ø Commensalism: l l Ø Both species benefit from the relationship Example = flower pollination by insects One member of the relationship benefits and the other is neither helped nor harmed Example = barnacles on whales Parasitism: l l One organism lives on (ectoparasite) or inside (endoparasite) another organism and harms it. Example = fleas on a dog

Ecological Succession Ø Ecosystems constantly change in response to natural and human disturbances Ø As an ecosystems changes older inhabitants gradually die out and new organisms move in = “ecological succession” l l Primary succession Secondary succession

Primary Succession that occurs on surface with NO soil Ø Example = on newly formed volcanic rock or on bare rock exposed when glaciers melt Ø 1 st species to populate = pioneer species Ø l l l Lichens (a fungus and an alga simbiont can live on bare rock) When they die lichens help form soil that allows new organisms to move in Lichens mosses grasses shrubs trees • What types of animals would you see at each stage?

Bare rock with lichens

Secondary Succession When a disturbance of some kind changes an existing community WITHOUT removing the soil Ø Example: land is cleared for farming, a wildfire burns a woodland Ø Myth of the climax community (a mature, stable community that does not undergo further succession) Ø l l No community is ever at this point Climate change and human disturbances are always at work.

Populations Homework: Ch. 5 vocab flashcards

How Populations Grow Ø Characteristics of Populations: l Geographic distribution (range) – • The area or range inhabited by a population l Population density – • The number of individuals per unit area l Growth rate – • Determined by # of births, # of deaths, # immigrated, # emigrated l Age structure – • The range of ages in a population

Population Growth Ø Factors that affect population size: l l # of births causes an increase in population size # of deaths causes a decrease in population size Immigration (the movement of individuals into an area) causes an increase Emigration (the movement of individuals out of an area) causes a decrease

Exponential Growth Ø Exponential growth occurs when the individuals in a population reproduce at a constant rate Ø Occurs only under ideal conditions l l Abundant space and food Protected from predators and disease Ø J-shaped curve

Logistic Growth Ø As resources become scarce, the growth of a population slows or stops l Birth rate may decrease, death rate may increase, immigration may increase, emigration may decrease, or any combination of these. Carrying capacity the largest # of individuals that a given environment can support Ø S-shaped curve Ø

Population Trends Fruit Fly Population Growth Rabbit Population Growth Days Generations # of fruit flies # of rabbits 5 10 1 100 10 50 2 105 15 100 25 1000 20 200 37 1600 25 300 55 2400 30 310 72 3350 35 320 86 8000 40 320 100 13, 150 1. Make a graph of each data table.

Population Trends: Data Analysis Answer the following in your notebooks!!! What type of growth pattern is exhibited by the fruit fly population? Is it the same as the rabbit population? Explain. Ø Does either graph indicate there is a carrying capacity? If so…when? What is the maximum # of individuals that can be supported at one time? Ø What might happen if a group of predators moved into the rabbits’ habitat during the 10 th generation and began eating rabbits? Ø

Limits to growth Ø Limiting Factors: l l l Ø In context of populations A factor that causes population growth to decrease Density-dependent OR Density-independent Examples that affect population size: l l l Competition Predation Parasitism and disease Drought and other climate extremes Human disturbances

Density-Dependent Factors Ø Depends on population size l Factor only becomes limiting when the population density reaches a certain level Ø Includes: l l Competition Predation Parasitism Disease

Competition Ø When populations get crowded, they compete for food, water, space, sunlight, and other essentials of life (resources become scarce). Ø Major force behind evolutionary change! Ø Can occur: l l Between members of the same species Between different species

Predation Ø In nature, populations are often controlled by predators Ø Predator-prey relationship l Interactions that affect population growth of both predator and prey Ø Example: l Remember the Wolf and deer population activity

Parasitism and Disease Ø Parasites range in size Ø Similar to predators l Take nourishment at the expense of the host (causing disease and/or death) Ø Example: l l l WOW bug pets They lay their eggs on a larva The eggs hatch and consume the larva

Density-Independent Factors Ø Affects different populations the same way regardless of population size Ø Examples include: l l Unusual weather Natural disasters Seasonal cycles Human activity

Human Population Growth Ø The size of the human population has grown over time.

Human Population Videos World Population growth Exponential Growth from 1 A. D. lecture Ø Ø Produced by Population Connection in 2000. Population Connection is a nonprofit, 501(c)(3) organization http: //www. youtube. com/watc h? v=4 Bbk. Qi. Qya. Y ØDavid Suzuki “Forces of nature” – speaking about exponential growth Øhttp: //www. youtube. com/watch? v=Q 9 xo. FCS 33 kg

Patterns of Human Population Growth Demography l Study of human populations Ø The Demographic Transition l When population growth in a country has slowed in response to industrialization. l Transition is complete when birthrate falls to meet deathrate (population growth stops) • More children survive to adulthood, more adults living to old age rd world countries have yet to undergo this process l 3 Ø Age Structure l Population profiles (# of people in different age groups) Ø

Humans in the Biosphere Ch. 6 vocab flashcards

Earth as an Island Ø We share a limited resource base Ø We all depend on the natural ecological processes that sustain these resources Ø Take the earth calculator test now… l l l How many earth’s do you need if everyone lived like you? Is it fair to use resources the way you do? What are some ways you could decrease your impact?

Human Activities that have transformed the Biosphere Ø Hunting and gathering l Ø Subsistence hunting Agriculture l l l Domestication of animals (overgrazing, increased water use) Traditional Modern Agriculture (increased irrigation, increased use of chemical fertilizers, new types of farming equipment) Green Revolution governments introduced new, intensive farming techniques to increase yields. • “miracle strains”: improved harvest • Monoculture: a single crop/species was planted to increase yield

Industrial Growth and Urban Development Ø Certain kinds of industrial processes: l Pollute air, water, and soil Ø Dense human communities: l Produce wastes that must be disposed of Ø Suburban sprawl: l Consumes farmland natural habitats Ø All place stress on plant and animal populations and on the biosphere’s life support systems!!!

The Tragedy of the Commons Ø “Any resource that is open to everyone (air or ocean) will eventually be destroyed because everyone can use it but no one is responsible for preserving it. ” Ø Constructed Response Prompt: l l (On the provided handout - write approx. ½ - 1 page) In your opinion is the “tragedy of the commons” true? Use evidence/quotes from the reading to support your answer.

Renewable vs. Nonrenewable Reources Ø Work with a partner. Ø Using your book or the computer: l Generate a list of 10 renewable resources and 10 nonrenewable resources.

Sustainable Use Ø With your partner choose one of the following resources: l l l Ø Land Forest Ocean Air Water What are some ways to use these resources in a sustainable way? l You have 20 minutes to put together a 1 minute presentation on the topic.

Biodiversity Ø “Sum total of the genetically based variety of all organisms in the biosphere” Ø One of the Earth’s greatest natural resources Ø Includes: l l l Ecosystem diversity Species diversity Genetic diversity

Threats to Biodiversity Ø Human Activity can reduce biodiversity by: l l l Altering habitats through development Hunting species to extinction Introducing toxic compounds into food webs • Failing septic systems (our water quality lab!!!) • DDT (biological magnification)– Rachel Carson’s book Silent Spring l Introducing foreign species into new environments (invasive species)

Charting a Course for the Future Ø 2 major global phenomena affect the biosphere: l Ozone depletion • UV light is a mutagen! l Global Warming • Caused by a natural warming trend AND Human activity!!!