Terrestrial Biomes PLANT LIFE. small, leafy plants. cactus & other waterstoring. small hard-leaved trees & scraggy shrubs

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1 Terrestrial Biomes of a particular species. Most species have an optimum range at which their growth will be The world s oceans make up 99% of the planet s biosphere and contain the maximized. Abiotic factors such as water, greatest diversity of life, particularly in tropical coral reefs. Rain forests, deserts, coral reefs, grasslands, and a rotting log are examples of ecosystems with solar energy, dissolved oxygen, salinity, nitrates, phosphates will affect various plant specialized populations. An ecosystem is a complex community of plants, species ability for growth and development. animals and microorganisms (biotic) linked by energy and nutrient flows that interact together and with their abiotic environment. Land-based ecosystems are known as biomes and are further classified by climate (precipitation temperature). In addition to nutrients and climate, other abiotic factors affecting biomes include Anything that is necessary for optimum growth and development that is in short supply is known as a limiting factor. Limiting factors create competition within a species as solar energy and water. Aquatic-based ecosystems are primarily described as well as between different species. freshwater or saltwater. The vertical depths and sunlight levels characterize aquatic biomes. (Refer to Water Resources Reading Materials) The most significant abiotic factor determining the type of terrestrial biome is climate. Climate is determined by distance from equator, altitude, proximity to bodies of water or relative humidity and other factors that affect the yearly precipitation and temperature range. BIOME YEARLY PRECIPITATION / TEMP ( O C)/ SOIL TYPE PLANT LIFE Typically as you move further from the equator or higher in altitude, the average temperature decreases. Cooler air can hold less water vapor, so often these areas are also much dryer. Terrestrial biomes near large bodies of water tend to have more stable temperatures due to the high specific heat of water. If the average temperature is warmer, the water is often in the form of vapor causing a high relative humidity. Tundra <25 cm / -15 to 3 / permafrost Deserts (hot & cold) Chaparral (scrub forest) Taiga (coniferous forest) Grasslands Deciduous forest <25 cm / -5 to 30 / sandy, coarse soil cm (winter) / -7 to 18 / shallow, infertile soil cm,/ -5 to 8 / acidic soil cm / 0 to 30 /, rich soil cm / 0 to 20 / high organic composition in soil Tropical rain forest cm, / 20 to 28 / low organic composition soil small, leafy plants cactus & other waterstoring plants small hard-leaved trees & scraggy shrubs waxy, needle-leafed trees (conifers) mat-forming grasses hardwood trees tall trees with associated vines adapted to low light Climate determines the average temperature and precipitation, the length of the growing season, and the quality of the soil, including levels of soil nutrients. The growing season is the period of time each year when it is warm enough for plants to grow. The timing and length of the growing season determine what types of plants can grow in an area. For example, near the poles the growing season is very short. The temperature may rise above freezing for only a couple of months each year. We can predict what types of flora and fauna will be successful in an area because each organism can live only within a specific range of tolerance for the physical and chemical variations that exist within their environment. The range of tolerance may vary slightly within the population due to the genetic variability

2 Terrestrial Biomes Because of the cold temperatures and short growing season, trees and other slowgrowing plants are unable to survive. The growing season gets longer from the poles to the equator. Near the equator, plants can grow year-round if they have enough moisture. A huge diversity of plants can grow in hot, wet climates. The timing of precipitation also affects the growing season. In some areas, most of the precipitation falls during a single wet season (such as in California), rather than throughout the year (such as in New England). In these areas, the growing season lasts only as long as there is enough moisture for plants to grow. Since climate affects the type of producers in a biome, the entire food chain that depends on those producers is affected. Additionally, the soil is affected by climate for similar reasons. Plants need soil that contains adequate nutrients and organic matter. Nutrients and organic matter are added to soil when plant litter and dead organisms decompose. In cold climates, decomposition occurs very slowly. As a result, soil in cold climates is thin and poor in nutrients. Soil is also thin and poor in hot, wet climates because the heat and humidity cause such rapid decomposition that little organic matter accumulates in the soil. The frequent rains also leach nutrients from the soil. Soil in temperate climates is typically thicker and richer in nutrients. It contains more organic matter and is the best soil for g r o w i n g m o s t p l a n t s. producers convert solar energy into chemical energy. However, since much of the energy is lost through respiration and heat, a better measurement to determine the available energy for higher trophic levels is to measure the net primary productivity (NPP). NPP accounts for the loss of energy as it moves up a food chain. NPP = GPP-respiration by producers or NPP = photosynthesis - respiration Both NPP and GPP are expressed in units of mass of carbon in a specified area over a specified time. For example grams of carbon in a square meter in one year or (g C/m 2. yr) Primary productivity tends to be highest in tropical rain forests and estuaries. In general, as you move away from the equator, primary productivity will decrease. Therefore, the biodiversity will also decrease due to the lack of available energy needed to support the various populations in the ecosystem. In general, as you move away from the equator, primary productivity will decrease. Therefore, the biodiversity will also decrease due to the lack of available energy needed to support the various populations in the ecosystem. The ecological efficiency in an ecosystem refers to the percent of usable chemical energy that is transferred as biomass from one trophic level to the next. Obviously, the more energy available at the base of a food chain, the more energy there will be for consumers at the top. Gross primary productivity (GPP) is a way to measure the available energy from producers. GPP is the rate at which primary

3 NAME Write true if the statement is true and false if the statement is false. 1. Climate is the most important abiotic factors affecting terrestrial biomes. 2. Climate is determined only by distance from the equator. 3. The northern temperate zone goes from the equator to the arctic circle. 4. The moisture of a biome is determined solely by precipitation. 5. When air masses cool, they can hold more water vapor. 6. Coastal areas may have warmer winters and cooler summers than inland areas. 7. Between the equator and 20 north latitude, the climate is very dry. 8. Warm, sunny areas have less evaporation than cool, cloudy areas. 9. Dry climates are found only where the weather is hot and sunny. 10. Air masses that have passed over a wide expanse of land carry little moisture. 11. Climate has no influence on the quality of soil in an area. 12. Adaptations to dryness include thick, barrel-like stems in plants. 13 Why do most terrestrial organisms depend on plants? List what plants need to grow What factors determine the growing season in a given location? What do plants need in soil? What type of soil is best for most plants? Why are soils thin and poor in hot, wet climates? - Circle all the answers that are correct 18. Major subdivisions of the biosphere are called: niches, habitats, climate zones, biomes 19. Plants need nutrients that are naturally added to soils in the process of: leaching, root growth, decomposition 20. Biodiversity is usually greater in biomes that are wetter, warmer, closer to the equator

4 the map according to the clues listed below. You may need to look at a map of North America if you get stuck. 1. The dotted lines represent the border between the U.S. and Mexico and Canada. All other lines show biome borders. the U.S. borders (dotted line) red. 2. Northern Canada and Alaska are tundra - color the tundra light blue 3. Most of Canada is boreal forest. the boreal forest dark green. 4. The west coast of the U.S. is mainly Temperate forest where California is. The east coast, all the way to the center of the country is also Temperate forest. the Temperate forest light green. 5. The Midwest (middle of the country) is temperate grassland. the grassland yellow. 6. The eastern edge of Mexico and Central America, Hawaii, and the Caribbean Islands are all tropical rain forests. those purple. 7. There is a northwest coniferous forest located in the far corner of the U.S (northwest). the northwest coniferous forest brown. 7. The great lakes and the lakes in Canada are freshwater. Find each freshwater lake and color it pink. 8. The bodies of water surrounding the continent are salt water. the coastal areas dark blue. 9. The western region of the U.S. as well as Northern Mexico is desert. the desert orange. 10. The western edge of Mexico is temperate forest. it the same color as you did the other temperate forests. 11. code the squares at the bottom to match your biome colors. 12. Label the countries: U.S.A., Canada, Mexico

5 1. Name the 3 main biomes of the United States (land only). 2. What two biomes are closest to where you live? 3. What U.S. state could a person visit a tropical rain forest in? 4. How about a temperate rain forest? 5. A person is driving from Los Angeles, California to Washington D.C. Name the biomes the person will pass through, in the correct order. 6. A person is driving from Alaska to Mexico, staying close to the west coastline. Name the biomes the person will pass through, in the correct order.

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7 Aquatic Ecosystems Vocabulary coral bleaching, salinity, plankton, nekton, benthos, phytoplankton, zooplankton, calcium carbonate, open sea, coastal zone, continental shelf, estuary, marsh, swamp, coastal wetlands, intertidal zone, barrier islands, oligotrophic lake, eutrophic lake, watershed WATER QUALITY LEGISLATION 1. Clean Water Act of 1977 deals in regulating point-source pollution from municipal sewage facilities and industries and financing wastewater treatment systems. The CWA has decreased annual wetland losses and increased the percent of the U.S. population served by sewage treatment plants. 2. Water Quality Act of 1987 is an amendment to the CWA that encourages the separation of storm water and sewer water lines. 3. Safe Drinking Water Act of 1974 requires the Environmental Protection Agency (EPA) to set standards of maximum containment levels for water pollutants that have negative health impacts for humans. 4. Public Health Security and Bioterrorism Preparedness and Response Act of assess community water systems infrastructure for any possible vulnerability to a terrorist or other intentional attack that would disrupt the ability to provide a clean, safe supply of water. Lakes vary greatly in surface area, depth and nutrient concentrations. Deep lakes have distinct zones that are defined by their depth and distance from shore: A. Limnetic zone: Upper layer of lake away from shore receives a large amount of sunlight that supports abundant growth of phytoplankton. Phytoplankton are primary producers that make up the base of the food chain and supply the majority of dissolved oxygen for aerobic consumers. B. Profundal zone: mid-level lake zone receives little sunlight and is low in nutrients and dissolved oxygen. Organisms living here must be adapted to colder water and pressure. C. Benthic zone: bottom lake zone containing mostly decomposers who feed on the organic waste that trickles down from the upper zones. D. Littoral zone: shallow zone closest to shore. Receives plenty of sunlight and nutrients. Supports a wide variety of life, including both submergent (underwater) and emergent (rooted in water, yet penetrates surface) plant life. FRESHWATER ECOSYSTEMS Freshwater zones can be divided into two main types: lentic (standing bodies of water such as lakes, wetlands, bogs and ponds) and lotic (moving bodies of water such as rivers and streams. Lakes (lentic zones) form as surface water runoff, groundwater and rainfall fill depressions int he earth s surface that have been created through tectonic, glacial, volcanic and human activity (reservoirs for dams). Riparian buffer zones are vegetated areas along both sides of water bodies that generally consist of trees, shrubs and grasses and are transitional boundaries between land and water environments. Riparian zones act as buffers to protect surface waters from con-tamination & are habitats for a large variety of animals & birds. Riparian zones aid in the protection of streambanks & shorelines & flood attenuation. They reduce sedimentation of water bodies by reducing the erosive potential of stream- banks. These areas also aid in improved aesthetic environment; water quality improvement, including soluble contaminant flow retardation; & dispersion of concentrated flow, thereby minimizing gully erosion. The plants provide aeration & reduce pollutants by plant uptake. Vegetation in conservation buffers recycles entrapped nutrients in the harvested material, provides permanent habitat for many types of fauna & offers shade, thereby reducing stream temperature. Riparian zones can provide a great amount of biodiversity to the landscape. Even the detritus that accumulates can provide a food source for plants and animals.

8 Aquatic Ecosystems Lakes are also classified by concentration of nutrients and primary productivity (production of organic materials from Carbon dioxide, mostly through photosynthesis) rates. Clear, deep lakes that have low nutrient levels and therefore limited primary productivity are referred to by ecologists as oligotrophic. These lakes are typically colder and support a wide variety of fish species due to high levels of dissolved oxygen. Once lakes have accumulated a high concentration of nutrients from runoff of sediment and organic material that support high levels of net primary productivity by producers, they are known as eutrophic. These lakes are often more shallow and murky than oligotrophic systems. When large amounts of nutrients are added to lake systems due to human activities, such as runoff of fertilizers; this is known as cultural eutrophication. WETLANDS (LENTIC ZONES) includes swamps (dominated with trees such as mangroves), marshes (dominated by grasses), flood plains and bogs. These ecosystems are away from coastlines and are covered with freshwater either all or part of the time. These areas have an abundance of biodiversity, high levels of net primary productivity, and provide numerous ecosystem services such as 1. natural recharge to groundwater system 2. habitat space to many organisms such as beavers, fish, migratory waterfowl. 3. provide a nursery for many aquatic species and spawning ground for many fish 4. filters toxins and excess nutrients from waterways 5. reduces flooding and erosion

9 freshwater biomes Freshwater is defined as having a low salt concentration usually less than 1%. Plants and animals in freshwater regions are adjusted to the low salt content and would not be able to survive in areas of high salt concentration (i.e., ocean). There are different types of freshwater regions: Ponds and lakes Streams and rivers Wetlands Ponds and lakes These regions range in size from just a few square meters to thousands of square kilometers. Scattered throughout the earth, several are remnants from the Pleistocene glaciation. Many ponds are seasonal, lasting just a couple of months (such as sessile pools) while lakes may exist for hundreds of years or more. Ponds & lakes may have limited species diversity since they are often isolated from one another & from other water sources like rivers & oceans. Lakes & ponds are divided into three different zones which are usually determined by depth & distance from the shoreline. The topmost zone near the shore of a lake or pond is the littoral zone. This zone is the warmest since it is shallow & can absorb more of the Sun's heat. It sustains a fairly diverse community, which can include several species of algae (like diatoms), rooted & floating aquatic plants, grazing snails, clams, insects, crustaceans, fishes, & amphibians. In the case of the insects, such as dragonflies & midges, only the egg & larvae stages are found in this zone. The vegetation & animals living in the littoral zone are food for other creatures such as turtles, snakes, & ducks. The near-surface open water surrounded by the littoral zone is the limnetic zone. The limnetic zone is well-lighted (like the littoral zone) and is dominated by plankton, both phytoplankton and zooplankton. Little light penetrates all the way through the limnetic zone into the profundal zone. The fauna are heterotrophs, meaning that they eat dead organisms and use oxygen for cellular respiration. Temperature varies in ponds and lakes seasonally. During the summer, the temperature can range from 4 C near the bottom to 22 C at the top. During the winter, the temperature at the bottom can be 4 C while the top is 0 C (ice). In between the two layers, there is a narrow zone called the thermocline where the temperature of the water changes rapidly. During the spring and fall seasons, there is a mixing of the top and bottom layers, usually due to winds, which results in a uniform water temperature of around 4 C. This mixing also circulates oxygen throughout the lake. Of course there are many lakes and ponds that do not freeze during the winter, thus the top layer would be a little warmer. Streams and rivers These are bodies of flowing water moving in one direction. They get their starts at headwaters, which may be springs, snowmelt or even lakes, and then travel all the way to their mouths, usually another water channel or the ocean. The characteristics of a river or stream change during the journey from the source to the mouth. The temperature is cooler at the source than it is at the mouth. The water is also clearer, has higher oxygen levels, and freshwater fish such as trout and heterotrophs can be found there. Towards the middle part of the stream/river, the width increases, as does species diversity numerous aquatic green plants and algae can be found. Toward the mouth of the river/stream, the water becomes murky from all the sediments that it has picked up upstream, decreasing the amount of light that can penetrate through the water. Since there is less light, there is less diversity of flora, and because of the lower oxygen levels, fish that require less oxygen, such as catfish and carp, can be found. Wetlands Wetlands are areas of standing water that support aquatic plants. Marshes, swamps, and bogs are all considered wetlands. Plant species adapted to the very moist and humid conditions are called hydrophytes. These include pond lilies, cattails, sedges, tamarack, and black spruce. Marsh flora also include such species as cypress and gum. Wetlands have the highest species diversity of all ecosystems. Many species of amphibians, reptiles, birds (such as ducks and waders), and furbearers can be found in the wetlands. Wetlands are not considered freshwater ecosystems as there are some, such as salt marshes, that have high salt concentrations these support different species of animals, such as shrimp, shellfish, and various grasses.

10 MARINE BIOMES Deep currents are located far below the surface and are created by differences in density rather than surface winds. Density of ocean water is controlled by salinity and temperature. Water in the ocean moves in currents. Deep warm water currents moving toward the poles cools and forms ice. As ice forms, the salinity of the remaining water increases. The increase in salinity causes an increase in density. The increase in density causes the water to sink. This cold, dense water flows along the ocean floor as a deep current. The sinking, or downwelling, carries oxygen and other gases from surface waters to deeper ocean waters. Upwelling carries nutrients from the ocean floor towards the surface. These nutrients cause growth of algae and phytoplankton, the base of the ocean s foodweb. Currents are influenced by weather, the position of the continents and the rotation of Earth. Surface currents are movements of water at or near the surface of the ocean. The Gulf Stream is an example of a surface current. Global winds and trade winds move the water on the surface. The Coriolis Effect deflects not only air, but ocean water as well. Surface currents in the Northern Hemisphere turn clockwise and counterclockwise in the Southern Hemisphere. Surface currents will deflect when they meet continents. Marine biomes include oceans, estuaries and coral reefs. An estuary is a partially enclosed body of water, and its surrounding coastal habitats, where saltwater from the ocean mixes with fresh water from rivers or streams. In fresh water the concentration of salts, or salinity, is nearly zero. The salinity of water in the ocean averages about 35 parts per thousand (ppt). The mixture of seawater and fresh water in estuaries is called brackish water and its salinity can range from 0.5 to 35 ppt. The salinity of estuarine water varies from estuary to estuary, and can change from one day to the next depending on the tides, weather, or other factors Estuaries are transitional areas that straddle the land and the sea, as well as freshwater and saltwater habitats. The daily tides (the regular rise and fall of the sea's surface) are a major influence on many of these dynamic environments. While strongly affected by tides and tidal cycles, many estuaries are protected from the full force of ocean waves, winds, and storms by reefs, barrier islands, or fingers of land, mud, or sand that surround them. The characteristics of each estuary depend upon the local climate, freshwater input, tidal patterns, and currents. Truly, no two estuaries are the same. Yet they are typically classified based on two characteristics: their geology and how saltwater and fresh water mix in them. Estuaries are found at mouths of rivers, inlets, bays, salt marshes, mangrove forests.

11 Healthy estuaries are critical for the continued survival of many species of fish and other aquatic life, birds, mammals, and reptiles. Estuaries are important natural places. They provide goods and services that are economically and ecologically indispensable. Often called nurseries of the sea (USEPA, 1993), estuaries provide vital nesting and feeding habitats for many aquatic plants and animals. Most fish and shellfish eaten in the United States, including salmon, herring, and oysters, complete at least part of their life cycles in estuaries. Estuaries also help to maintain healthy ocean environments. They filter out sediments and pollutants from rivers and streams before they flow into the oceans, providing cleaner waters for marine life. Estuaries are often the economic centers of coastal communities. Estuaries provide habitat for more than 75 percent of the U.S. commercial fish catch, and an even greater percentage of the recreational fish catch (National Safety Council s Environmental Center, 1998). The total fish catch in estuaries contributes $4.3 billion a year to the U.S. economy (ANEP, 1998). Many estuaries support healthy recreational fisheries. This, in turn, provides financial security for communities that rely on tourists to support their economies. Estuaries are also important recreational areas. Millions of people visit estuaries each year to boat, swim, watch birds and other wildlife, and fish. Coastal recreation and tourism generate from $8-$12 billion per year in the United States alone (National Safety Council s Environmental Center, 1998). Many estuaries are important centers of transportation and international commerce. Many of the products you use every day pass through one or more estuaries on a commercial shipping vessel before ever reaching your home Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny animals found in marine waters that contain few nutrients. Often called "rainforests of the sea", coral reefs form some of the most diverse ecosystems on Earth. They occupy less than 0.1% of the world's ocean surface, yet they provide a home for roughly 25% of all marine species, including fish, mollusks, worms, crustaceans, echinoderms, sponges, tunicates and other cnidarians. Paradoxically, coral reefs flourish even though they are surrounded by ocean waters that provide few nutrients. They are most commonly found at shallow depths in tropical waters, but deep water and cold water corals also exist on smaller scales in other areas. Coral reefs deliver ecosystem services to tourism, fisheries and shoreline protection. The annual global economic value of coral reefs is estimated between $ billion. However, coral reefs are fragile ecosystems, partly because they are very sensitive to water temperature. They are under threat from climate change, oceanic acidification, blast fishing, cyanide fishing for aquarium fish, overuse of reef resources, and harmful land-use practices, including urban and agricultural runoff and water pollution, which can harm reefs by encouraging excess algal growth. OCEAN ACIDIFICATION causes weakened shells and coral skeletons due to a calcium deficiency. The loss of these organisms affects the habitat and food chain of the entire ecosystem.

12 Marine biomes are aquatic biomes found in the salt water of the ocean. Major marine biomes include neritic, oceanic, and benthic biomes. Neritic and oceanic biomes are described in the rest of this passage. Neritic biomes occur in ocean water over the continental shelf. They extend from the low-tide water line to the edge of the continental shelf. The water here is shallow, so there is enough sunlight for photosynthesis. The water is also rich in nutrients, which are washed into the water from the nearby land. Because of these favorable conditions, large populations of phytoplankton live in neritic biomes. They produce enough food to support many other organisms, including both zooplankton and nekton. As a result, neritic biomes have relatively great biomass and biodiversity. They are occupied by many species of invertebrates and fish. In fact, most of the world s major saltwater fishing areas are in neritic biomes. Oceanic biomes occur in the open ocean beyond the continental shelf. There are lower concentrations of dissolved nutrients away from shore, so the oceanic zone has a lower density of organisms than the neritic zone. The oceanic zone is divided into additional zones based on water depth. The epipelagic zone is the top 200 meters of water, or the depth to which enough sunlight can penetrate for photosynthesis. Most open ocean organisms are concentrated in this zone, including both plankton & nekton. The mesopelagic zone is between 200 & 1,000 meters below sea level. Some sunlight penetrates to this depth but not enough for photosynthesis. Organisms in this zone consume food drifting down from the epipelagic zone, or they prey upon other organisms in their own zone. Some organisms are detrivores, which consume dead organisms & organic debris as they drift down through the water. The bathypelagic zone is between 1,000 & 4,000 meters below sea level. No sunlight penetrates below 1,000 meters, so this zone is completely dark. Most organisms in this zone either consume dead organisms drifting down from above or prey upon other animals in their own zone. There are fewer organisms & less biomass here than in higher zones. Some animals are bioluminescent, which means they can give off light. This is an adaptation to the total darkness. The abyssopelagic zone is between 4,000 & 6,000 meters below sea level & is completely dark. It has low biomass & low species diversity. The hadopelagic zone is found in the water of deep ocean trenches below 6,000 meters. It is totally dark & has very low biomass & very low species diversity.

13 Write true if the statement is true and false if the statement is false. 1. Most aquatic organisms have to deal with extremes of temperature. 2. Aquatic biomes have more total biomass than terrestrial biomes. 3. There is generally plenty of oxygen to support organisms in the photic zone. 4. Oceanic biomes occur in ocean water over the continental shelf. 5. Nekton are aquatic organisms that can make their own food. 6. Sponges and clams are examples of benthic organisms. 7. Water at the bottom of the ocean is always cold. 8. The intertidal zone has very low biodiversity. 9. Corals are colored rocks found at the bottom of tropical ocean water. 10. The depth of the photic zone in a lake depends on clarity of water. 11. Plants are important producers in ocean water biomes. 12. Both riparian zones and wetlands help prevent erosion. a. Deep ocean water may contain more nutrients than surface water due to a. decomposition of marine organisms. b. photosynthesis by photic organisms. c. runoff from nearby land. d. turnover of deep ocean water. b. Plankton consists of a. algae. b. bacteria. c. animals. d. all of the above. c. In ocean zones deeper than 200 meters, most organisms are a. consumers. b. producers. c. phytoplankton. d. zooplankton. d. How do organisms in the hadal zone of the ocean make food? a. photosynthesis b. chemosynthesis c. decomposition d. predation e. Based on the availability of sunlight, lakes are divided into the littoral zone, limnetic zone, profundal zone, and a. intertidal zone. b. benthic zone. c. pelagic zone. d. epipelagic zone. f. Compared with lakes that have low nutrient levels, lakes that have high nutrient levels have a. higher productivity. b. clearer water. c. lower biodiversity. d. more dissolved oxygen. g. Any area that is saturated or covered by water for a least one season of the year is classified as a a. wetland. b. riparian zone. c. littoral zone. d. coral reef.

14 NAME Match the vocabulary term with the correct definition. Term 1. abyssal zone 2. aphotic zone 3. bathyal zone 4. benthic zone 5. hadal zone 6. intertidal zone 7. littoral zone 8. mesopelagic zone 9. neritic zone 10. riparian zone Definition a. part of the ocean floor that makes up the continental slope b. narrow strip along the coastline of the ocean that is exposed to air at low tide c. part of the ocean floor that is under the deep ocean d. part of the pelagic zone over the continental shelf e. bottom surface of the ocean or a lake f. water between 200 and 1,000 meters below sea level in the oceanic zone g. interface between running freshwater and land h. deep water where too little sunlight penetrates for photosynthesis to occur i. part of the ocean floor that is in deep ocean trenches j. shallow water near the shore of a lake or the ocean

15 COMMUNITIES & INTERACTIONS The levels of ecological hierarchy are as follows: 1. organism - individual form of life 2. species - organisms that can reproduce fertile offspring 3. population - group of a species living in one area at one time 4. community - group of different populations and their interactions 5. ecosystem - communities and their abiotic surroundings 6. biome - major biotic communities characterized by dominant plant life & climate 7. biosphere - anywhere life is found (aquatic, terrestrial, atmosphere) Life comes in many forms. A small pond or untended plot of land may contain dozens or even hundreds of different kinds of plants and animals. In contrast, a carefully tended lawn or a commercial timber plantation usually supports only a few types of grasses or trees. The total number of organisms in the plantation or lawn may be the same as the number in the pond or untended plot, but the number of species will be far smaller. Within a given region, the variety of ecosystems is a measure of the ecosystem diversity. Within a given ecosystem, the variety of species constitutes species diversity. Within a given species, we can think about the variety of genes as a measure of genetic diversity. The number of species in any given place is the most common measure of biodiversity. Estimating biodiversity can be a challenge. Many species are active only at night, or are microscopic or live in places that are not accessible. Scientists have named approximately 2 million species, but the total must be larger than that. It is estimated there are 8 million species of beetle in a section of the Amazon Rain Forest alone. Species richness is the number of a species in a given area, such as a pond. Species richness is used to give an approximate sense of biodiversity in a particular place. Species evenness tells us if an ecosystem is numerically dominated by one species or whether all of its species have similar abundances.

16 Simpson s Index You have studied a specific site, and have counted the individuals of five different species. n is the total number of organisms of a particular species. n n - 1 n(n - 1) Species A Species B Species C Species D Species E n(n - 1) 264 N = total number of all individuals = 35 N - 1 = 34 N(N - 1) = 1190 Many diversity indices have been developed that combine different measures of biodiversity. One is called the Simpson s Index. The Simpson s Index includes BOTH species richness and species evenness in a single number. D is the Simpson s Index n is the total number of organisms of a particular species N is the total number of organisms of all species means add up! D = = This area would score on the Simpson s Index. The scale ranges from 0 1, with 1 representing the lowest biodiversity. Therefore, the score for this area indicates a high level of biodiversity. D = n(n - 1) N(N - 1)

17 This activity uses beads of different colors to look at the concepts species richness and evenness and how they relate to biodiversity and conservation. Imagine that each color represents a species of animal, and each bead represents one individual of that species. 1 Without looking into the bag, reach in and pull out one bead from Bag A. Record its color in column 1 of the following table. Put the bead back in the bag and pull out a new bead. Record the color in column 2. Repeat to complete the row. Use single-letter abbreviations for the colors (red = R, black = B, etc.). Do the same for Bag B. Table Bag A Bag B 2 Using the numbers from Table 1, add up the number of beads of each color, for each bag, and record the totals in the following table. (Enter the colors of your beads at the head of the columns). Table Bag A Bag B 3 Refer to data from tables 1 and 2 to contrast and compare the species richness and evenness.

18 4 Dump out all of the beads in Bag A and count them. How many beads of each color are there in Bag A? Record the total number of each in the following table. (Enter the colors of your beans at the head of the columns). Repeat for Bag B. Table Bag A Bag B 5 If each color of bean represents a species, and each bean represents one individual, how many species does each bag have? Does one bag have more than the other? Can you apply the terms "species richness" and "species evenness" to the bags? 6 Which species, in which bag is the most rare? 7 If you had the money and resources to save only one of the sites (A or B), which would you save? Why?

19 10. Calculate the biodiversity using the Simpson s Index for Bag A using the data from Table 2, and again for Table 3. Show your work. CALCULATIONS FOR TABLE 2 CALCULATIONS FOR TABLE 3

20 While you wait to do the Biodiversity Activity: Read in the Environmental Science for AP textbook pages Answer questions 1-10, Drug Resistant E.coli question, parts a, b and d; and Measuring Your Impact question parts a, b and d #1 #6 #2 #7 #3 #8 #4 #9 #5 #10 Drug Resistance a) 4pts. b) 2pts. d) 2pts. Measuring Impact - Show Equation, answer with correct units. a) 2 pts. b) 2 pts. d) 2pts.

21 Changes in ecosystems CLIMATE CHANGE The Intergovernmental Panel on Climate Change (IPCC) has gathered hundreds of scientists to examine the record-setting rise in global temperatures. A 2006 IPCC report stated with 90% certainty that the temperature rise seen in the past century is due to rising greenhouse gases. These gases absorb infrared heat radiation energy from the Earth that would otherwise radiate out to space. This atmospheric warming adds to natural greenhouse heating and causes even higher temperatures. Global temperatures have fluctuated over millions of years with periods of cold temperatures causing ice ages. In modern times, however, the rates of change have often been much higher than those that occurred historically. Changing climate temperatures impact coral reefs and forest ecosystems, along with related industries and jobs such as lumber and fishing. The melting of the polar ice cap is another example of changes taking place around the globe. Global climate change refers to changes in the climate of Earth - the average weather that occurs in an area over a period of years or decades. Changes attributable to activities of man are classified as anthropogenic. The increase in atmospheric greenhouse gases is mostly due to combustion of fossil fuels and deforestation. Clearing large areas of vegetation for urban growth, agriculture, mining, etc., decreases transpiration rates, which can decrease precipitation in some areas as well as reduce infiltration of water into soils. This also increases the chance of flooding as well Public policy in many countries has begun to address climate issues at the national, regional and international levels. Conservation and sustainable biodiversity activities are becoming more common with a strong focus directed toward sustainable use. Sustainable use is the use of resources in a way that protects the numbers and complexity of a species or environment without causing long-term loss. Four major greenhouse gases are carbon dioxide, methane, nitrous oxide, and halocarbons (perfluorocarbons, hydrofluorocarbons and sulfur hexafluoride). The approximate residence time (how long they stay in the atmosphere) is as follows: Carbon dioxide years Methane - 12 years Nitrous oxide years Halocarbons - from several weeks up to 50,000 years. Sources of anthropogenic carbon dioxide is from fossil fuels such as coal, oil and natural gas. Natural sources are cellular respiration, decaying biomass, natural forest fires. Plants take in carbon dioxide from the atmosphere during photosynthesis, so deforestation plays a negligible part in increasing the amount of carbon dioxide in the atmosphere Breakdown of anthropic greenhouse gas emissions by gas, in billion tons carbon equivalent in Source: IPCC 2007

22 Methane (CH4) generates a little over 15% of the human induced greenhouse effect. Methane is formed as organic compounds decay in the absence of oxygen, for example under water or under ground. Most methane in the atmosphere is from swamps, termites, emissions from ruminants (cows, sheep, goats...), landfills, ventilation of coal mines and processing of fossil fuels. There are no natural sources of halocarbons. These gases are used as fluids for any device that generates cold, such as refrigerators, freezers, and air conditions. They are also found as propellants in sprays. Halocarbons are also used in manufacturing plastic foams and semiconductors used in cellular phones. The Montreal Protocol has banned the use of one type of halocarbon because of their effect on the stratospheric ozone layer. Nitrous oxide (N2O) is a by-product of microbial activity in the soil and is part of the nitrogen cycle. Therefore, some nitrous oxide is naturally found in the atmosphere. The human contribution comes from use of fertilizers and in some chemical industries. Agriculture is the largest source of anthropogenic nitrous oxide. In addition to fertilizers, some is emitted during the breakdown of nitrogen in livestock manure and urine. Other human sources are from combustion of transportation fuels. Tropospheric ozone (O3) is a pollutant that is a variant of oxygen gas. (O2). fossil fuel combustion mostly from road and air transportation. It is indirectly a result of A major gas responsible for the greenhouse effect that is not anthropogenic is water vapor. Water has a high specific heat, allowing it to act as a natural sink for heat energy. Any change in the climate of an area can affect the plants and animals living there, as well as the makeup of the entire ecosystem. Most plants and animals live in areas with very specific climate conditions, such as temperature and rainfall patterns, that enable them to thrive. Some species are already responding to a warmer climate by moving to cooler locations. For example, some North American animals and plants are moving farther north or to higher elevations to find suitable places to live. Climate change also alters the life cycles of plants and animals. For example, as temperatures get warmer, many plants are starting to grow and bloom earlier in the spring and survive longer into the fall. Some animals are waking from hibernation sooner or migrating at different times, too. As the Earth gets warmer, plants and animals that need to live in cold places, like on mountaintops or in the Arctic, might not have a suitable place to live. If the Earth keeps getting warmer, up to one fourth of all the plants and animals on Earth could become extinct within 100 years. Every plant and animal plays a role in the ecosystem (for example, as a source of food, a predator, a pollinator, a source of shelter), so losing one species can affect many others. Just like people, plants and animals will have to adapt to climate change. Many types of birds in North America are already migrating further north as the temperature warms. People can help these animals adapt by protecting and preserving their habitats. Coral reefs are created in shallow tropical waters by millions of tiny animals called corals. Each coral makes a skeleton for itself, and over time, these skeletons build up to create coral reefs, which provide habitat for lots of fish and other ocean creatures. Warmer water has already caused coral bleaching (a type of damage to corals) in many parts of the world. By 2050, live corals could become rare in tropical and sub-tropical reefs due to the combined effects of warmer water and increased ocean acidity caused by more carbon dioxide in the atmosphere. The loss of coral reefs will reduce habitats for many other sea creatures, and it will disrupt the food web that connects all the living things in the ocean. To help give coral reefs a better chance of surviving the effects of climate change, swimmers, boaters, and divers should treat these fragile ecosystems with care. People can also support groups working to protect coral reefs.

23 Changes in ecosystems ECOLOGICAL SUCCESSION A change in community composition following a disturbance is called ecological succession. Ecologists divide successions into two major types: primary succession and secondary succession. Primary succession begins on sites that lack living organisms. Secondary succession begins on sites where some organisms have survived the most recent disturbance. The patterns and causes of ecological succession are varied, but the species that colonize a site soon after the disturbance often alter environmental conditions so that they become favorable for other species. These species are called pioneer species. An example of primary succession is the change in the plant community that followed the retreat of a glacier in Glacier Bay, Alaska, over the last 200 years. No human observer was present to measure changes over the 200-year period, but ecologists have inferred the temporal pattern of succession by measuring plant communities on gravel deposits formed where the glacier front was stationary for a number of years from different periods. By looking at different ages, ecologists have been able to deduce the process of primary succession at Glacier Bay, Alaska. The pattern of succession in this area illustrates how succession is caused in part by changes in the soil brought about by the plants themselves. Primary succession also follows events such as lava flow or volcanic activity that forms new islands. Secondary succession follows a disturbance in the ecosystem, but the soil is left in tact along with some of the organisms living in the soil. Disturbances that cause secondary succession include hurricanes, forest fires and deforestation. Since the soil is present, there is no need for pioneer species.

24 Vocabulary Vocabulary Vocabulary Vocabulary Ecosystem, temperate rainforest invasive species biotic, tropical rainforest keystone species abiotic, boreal forest (Taiga) indicator species limiting factors, ecological efficiency, GPP, NPP, biosphere, biome, sustainable use, endemic species, range, extinct, wetlands, hotspots, ecological niche, habitat, primary succession, secondary succession, gene pool, natural selection, adaptation aphotic photic littoral zone riparian buffer zone coral reef neritic zone tundra desert Grassland estuary ocean acidification Clean Water Act Water Quality Act Safe Drinking Water Act Public Health Security and Bioterrorism Preparedness and Response Act oligotrophic eutrophic species populations community ecosystem biome biosphere niche interspecific competition intraspecific competition predation parasitism mutualism commensalism k strategist r strategist native species competitive exclusion principal resource partitioning ecological succession primary succession secondary succession pioneer species biodiversity Simpson s Index species richness species evenness microevolution macroevolution mutation artificial selection natural selection fitness genetic drift geographic isolation reproductive isolation GMOs range of tolerance fundamental niche realized niche generalists specialists residence time anthropogenic