Objectives Define ecology Describe the levels of organization

Objectives § Define ecology § Describe the levels of organization that ecologists study § Identify the source of energy for life processes § Trace the flow of energy through living systems § Evaluate the efficiency of energy transfer among organisms in an ecosystem § Describe how matter cycles among living and nonliving parts of an ecosystem § Explain why nutrients are important in living systems § Describe how the availability of nutrients affects the productivity of ecosystems

§ Ecology is the scientific study of interactions among organisms and between organisms and their environment, or surroundings. § All organisms depend on both the environment and other organisms to survive

Levels of Organization § Individual - one member of a particular species § Populations - groups of individuals that belong to the same species and live in the same area § Communities - collection of different populations that live together in a defined area

§ Ecosystem - collection of all organisms that live in a particular place together with their nonliving, or physical, environment § Biome - groups of ecosystems that have the same climate and dominant communities § Biosphere- contains the combined portions of the planet in which all of life exists, including land, water, and air, or atmosphere

ENERGY FLOW § All organisms need energy § Energy flows through ecosystems

Producers/Autotrophs § Sunlight is the main energy source for life on Earth § Photoautotrophs use photosynthesis § Plants, algae, and cyanobacteria § Some types of organisms rely on the energy stored in inorganic chemical compounds § Chemoautotrophs use chemosynthesis § Sulfur bacteria- hot springs/deep sea vents

Consumers/Heterotrophs § Organisms that rely on other organisms for their energy and food supply § Herbivores obtain energy by eating only plants § Carnivores eat animals § Omnivores eat both plants and animals. § Detritivores feed on plant and animal remains and other dead matter (detritus) § Decomposers breaks down organic matter

Feeding Relationships § Energy flows through an ecosystem in one direction § sun or inorganic compounds autotrophs (producers) heterotrophs (consumers) § Food chain- series of steps in which organisms transfer energy by eating and being eaten

§ Feeding relationships are more complex than can be shown in a food chain § Food webs- network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem § Link several food chains together

§ Each step in a food chain or food web is called a trophic level § Producers- 1 st level § Consumers- 2 nd, 3 rd, or higher trophic levels § consumers depend on the trophic level below it for energy. Critical Thinking, p. 829

Ecological Pyramids § diagrams that show the relative amounts of energy or matter contained within each trophic level in a food chain or food web § Energy pyramid § Only part of the energy that is stored in one trophic level is passed on to the next level § ~10 % of the energy available within one trophic level is transferred to organisms at the next trophic level

Energy Digested FOOD Undigestible Unedible Nutrients (building – repair of tissues) WASTE

§ Biomass pyramid § represents the amount of potential food available for each trophic level in an ecosystem.

§ Pyramid of Numbers § Shows the relative number of individual organisms at each trophic level

Abiotic v. Biotic Factors § Organisms in ecosystems are affected by both § Biotic factors are all of the living things with which organisms interact § Abiotic factors are nonliving, physical things § The above determine the survival and growth of an organism and the productivity of the ecosystem in which an organism lives

Abiotic Factors Biotic Factors ECOSYSTEM

Habitat v. Niche § A habitat is the area where an organism lives. § A habitat has both biotic and abiotic factors. § A niche includes all of the abiotic and biotic things in an organism’s habitat and the way the organism uses those things § For example, a niche includes what an organism eats and how it gets its food

Figure 4 -5 Three Species of Warblers and Their Niches Cape May Warbler Feeds at the tips of branches near the top of the tree Bay-Breasted Warbler Feeds in the middle part of the tree Spruce tree Yellow-Rumped Warbler Feeds in the lower part of the tree and at the bases of the middle branches

Community Interactions §Community interactions can powerfully affect an ecosystem § Competition occurs when living things try to use the same resources. Competition often results in one organism dying out § Predation occurs when one organism (the predator) captures and eats another (the prey) § Symbiosis occurs when two species live close together in one of three ways § Mutualism: Both species benefit from the relationship § Commensalism: One species benefits. The other is neither helped nor harmed § Parasitism: One species benefits by living in or on the other. The other species is harmed.

Ecological Succession § Ecosystems can change § natural and human disturbances. § older inhabitants gradually die out and new organisms move in

§ Ecological succession is the series of predictable changes that occur in a community over time § Primary succession takes place on bare rock surfaces where no soil exists. § Pioneer species are the first species to live in these areas § Secondary succession occurs when a disturbance changes a community without removing the soil.

Predator/Prey: Simulation Review § http: //www. phschool. com/atschool/phbio/ active_art/predator_prey_simulation/inde x. html

Ecological Review: § https: //www. youtube. com/watch? v=ysa 5 OBh. Xz-Q § Complete population ecology – yellowstone elk worksheet (5)

CYCLES OF MATTER § matter is recycled within and between ecosystems § Elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another through biogeochemical cycles

Water Cycle § Water falls to Earth’s surface as precipitation § Some water reenters the atmosphere by evaporation and transpiration § Transpiration - plants take in water through their roots and release water through tiny openings in their leaves § Some water runs into streams, lakes, rivers, and oceans – “runoff” § Other water seeps through the soil and into the ground water – “seepage”

Nutrient Cycles § Every living organism needs nutrients to build tissues and carry out essential life functions

§ Carbon Cycle § Biological processes = photosynthesis, respiration, and decomposition § Geochemical processes = release of carbon dioxide to the atmosphere by volcanic activity § Mixed biogeochemical processes, such as the burial of carbon-rich remains of organisms and their conversion into coal and fossil fuels § Human activities = mining, cutting and burning forests, and burning fossil fuels lead to increase of CO 2 § https: //ed. ted. com/lessons/the-carbon-cyclenathaniel-manning/review_open#question-6

CO 2 in Atmosphere CO 2 in Ocean

§ Nitrogen Cycle § All organisms need nitrogen to make proteins and nucleic acids § Nitrogen-fixing bacteria live in the soil or in the roots of plants § Nitrogen fixation - converting nitrogen gas into ammonia § Other bacteria in the soil convert ammonia into nitrates and nitrites § Plants use the byproducts § Animals get nitrogen by eating plants and other animals § Some bacteria convert the nitrates and nitrites back to nitrogen gas § ed. ted. com/on/f 2 b. WWgs. M#watch

§ Phosphorus Cycle § P, helps form DNA and RNA § Phosphorus remains mostly on land in rock and soil minerals, and in ocean sediments § Erosion releases phosphorus from the rocks § Some of the phosphate washes into rivers and streams, and eventually makes its way to the oceans, where it is used by marine organisms § https: //ed. ted. com/on/Jippl. NEs/review_open #question-6

Nutrient Limitation § One factor that controls the primary productivity of an ecosystem is the amount of available nutrients § Lack of a nutrient can limit an organism’s growth § When an ecosystem is limited by a single nutrient that is scarce or cycles very slowly, this substance is called a limiting nutrient § Oceans- nitrogen, iron, or silica § Freshwater- phosphorus

Objectives § Identify the causes of climate § Explain how Earth’s temperature range is maintained § Identify Earth’s three main climate zones § Explain how biotic/abiotic factors influence an ecosystem § Identify interactions that occur within communities § Describe how ecosystems recover from a disturbance § Explain what microclimates are § Identify the characteristics of major land biomes § Identify the factors that govern aquatic ecosystems § Identify the two types of freshwater ecosystems § Describe the characteristics of the marine zones

ROLE OF CLIMATE Climate v. Weather § In the atmosphere, temperature, precipitation, and other environmental factors combine to produce weather and climate § Weather is the day-to-day condition of Earth’s atmosphere at a certain time and place § Climate is the average yearly condition of temperature and precipitation in a region § Climate affects ecosystems

Greenhouse Effect § Carbon dioxide, methane, water vapor, and atmospheric gases trap heat energy and maintain Earth’s temperature range § These gases function like the glass windows of a greenhouse § Therefore, the trapping of heat by gases in the atmosphere is called the greenhouse effect § This greenhouse effect helps temperatures on Earth stay within a range that supports life

Effect of Latitude on Climate § Latitude also affects climate. Earth has three main climate zones: polar, temperate, and tropical § Polar zones are cold areas where the sun’s rays strike Earth at a very long angle § Temperate zones sit between the polar zones and the tropics § climate ranges from hot to cold, depending on the season § Tropical zone (tropics) near the equator § climate here is almost always warm

Different Latitudes 90°N North Pole Sunlight Arctic circle Sunlight Most direct sunlight 66. 5°N Tropic of Cancer Equator 0° Tropic of Capricorn Sunlight Arctic circle Sunlight 23. 5°N 66. 5°S 90°S South Pole 23. 5°S

Heat Transport in the Biosphere § Unequal heating of Earth’s surface also causes winds and ocean currents § Winds and currents move heat through the biosphere § Form because warm air/water rises and cold air/water sinks § Ocean currents warm/cool the air above them, affecting the weather and climate of nearby landmasses § Lake effect snow

LAND BIOMES § A biome is a group of land communities that covers a large area and has a certain soil type and climate. § Within a biome, there may be microclimates. § A microclimate is a small area where the climate differs from that of the surrounding area. § Peruvian oasis in S. America § A species may live over a large or small area, depending on its ability to survive and reproduce under tough conditions.

Major Biomes § There are ten major biomes: § tropical rain forest § tropical dry forest § tropical savanna § desert § temperate grassland § temperate deciduous forest § boreal forest (or taiga, or N. coniferous forest) § tundra

Tropical rain forest Temperate grassland Temperate forest Tundra Tropical dry forest Desert Tropical savanna Temperate woodland shrubland Northwestern coniferous forest Mountains and ice caps Boreal forest (Taiga) § Each biome has its own set of abiotic factors and a typical collection of organisms § Some areas, such as mountains and polar ice caps, do not fall neatly into the major biomes.

Ten Major Biomes Biome Precipitation Temperature Soil Diversity Trees Grasses Tropical Rain Forest high hot poor high dense sparse Tropical Dry Forest variable mild rich moderate medium Tropical Savanna variable Desert low Temperate Grassland moderate mild variable summer hot clay poor rich moderate sparse absent dense sparse dense Temperate Deciduous Forest moderate summer moderate, rich winter cold high dense sparse Northwestern Coniferous Forest/ Boreal Forest/ Taiga Tundra High-moderate summer mild, winter cold poor, acidic moderate dense sparse low summer mild, winter cold poor low absent medium Page 860 questions 2, 5 -10 11 -17 *CHOOSE 5 to answer

AQUATIC ECOYSTEMS § described mainly by the depth, flow, temperature, and chemistry of their water

Freshwater Ecosytems § Freshwater ecosystems can be divided into several types. § Flowing-water ecosystems (rivers and streams) flow over land. § Standing-water ecosystems include lakes and ponds. § Freshwater wetlands include bogs, marshes, and swamps. § In wetlands, water covers the soil or is present at or near the surface for at least part of the year.

Estuaries § where rivers meet the sea § mixture of fresh and salt water. § Salt marshes are temperate estuaries. § Salt-tolerant grasses and seagrasses are the dominant plant life § Mangrove swamps are tropical estuaries § several species of salt-tolerant trees, called mangroves, and seagrasses.

Marine ecosystems (Oceans) § The ocean is divided into zones based on how much light penetrates the water § The photic zone is the well-lit upper layer of water § Photosynthesis can take place here § The aphotic zone is the permanently dark lower layer of water § Producers here use chemosynthesis to make food

land 200 m Coastal ocean 1000 m Open ocean 4000 m 6000 m Ocean trench 10, 000 m Continental shelf Photic zone Continental slope and continental rise Abyssal plain Aphotic zone