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Kinds of Ecosystems J. Quigley- 2016 Biomes • Earth is covered by hundreds of types of ecosystems. For convenience ecologists group these ecosystems into a few biomes Biomes • Biomes are areas that have distinctive climates and organisms • Each biome contains many individual ecosystems • Locations of all the major biomes are mapped out Biomes • Biomes are usually named for the plant life they contain • Climate determines plant life. • Plant life determines animal life • Animal and plant life determine bacteria, other microorganisms and decomposers in the area Biomes • The major biomes are: – – – – – – – – Tropical rain forest Temperate forest Taiga Savanna, temperate grasslands and chaparral Desert Tundra Mountains/Ice Water Tropical Rain Forests • Tropical Rain Forest: occurs in a belt around the earth near the equator • Always humid and warm • Gets about 250cm of rain each year • Strong sunlight year round • Fairly constant climate and little seasonal variation in temperature Tropical Rain Forests • Tropical Rain Forests have a climate ideal for growing plants which flourish year round • The warm and wet conditions nourish more plant species than any other biome • The soil is thin and poor, but the rapidly decaying plants and animals after death returns nutrients to the soil to be used again • Because the soil is thin, most tropical rain forest plants have roots that grow sideways instead of deep. Tropical Rain Forests • Rainforest plant adaptations: trees and plants grow in layers – Trees more than 30m tall form the dense canopy that absorbs at least 95% of the sunlight – Below the canopy is the understory, only trees and shrubs adapted to shade can live here; When a tree dies, seedlings grow quickly to outcompete other trees for the new space – Forest floor is the bottom layer Tropical Rain Forests • Tropical rain forest animal adaptations – The incredible diversity of rain forest vegetation may have lead to the evolution of the greatest diversity of animals anywhere on earth – Most rainforest animals are specialists – A specialist is an organism adapted to use a specific resource in a particular way to avoid competition. Tropical Rain Forests • Tropical Rain Forest Adaptations: – Some animals have evolved elaborate methods for escaping predators – Other have evolved equally sophisticated methods for capturing prey – Camouflage and mimicry is common Forests • Threats to the rain forest: – The rain forest used to cover 20% of the entire earth, today it is less than 7%. – This is due to logging, clear cutting and farming – You can help the rain forest by buying products that promote sustainable use of rainforests Temperate Rain Forest • Temperate rain forests occur in North America, South America, Australia and New Zealand. • The Pacific NW is home to North America’s only temperate rain forests… where tree branches are draped with mosses, tree trunks are covered in lichens and the forest floor is covered in lush ferns Temperate Rain Forest • 300 foot tall evergreen trees such as Sitka Spruce and Douglas Fir dominate the forest • Moisture is very high in this cool, humid forest • It has high rainfall and moderate temperatures • It has become the subject of controversy in recent years because of conflicts over logging. Temperate Deciduous Forests • A walk though N. American deciduous forest in the fall is very colorful. • Deciduous trees lose their leaves every fall and grow them back every spring. Deciduous trees are dominant in this forest Temperate Deciduous Forests • Trees drop their broad, flat leaves each fall • Seasonal variations can be extreme • The growing season lasts for four to six months • Summer temperatures are about 35⁰C (95⁰F) • Winter temperatures are well below freezing Temperate Deciduous Forests • Deciduous forests are moist, receiving between 75-250cm (300-100 inches) of rainfall each year • The rain and snow help decompose dead organic matter, such as fallen leaves, which in turn contributed to the rich, deep soil. Temperate Deciduous Forests • Plant Adaptations: Similar to the tropical rain forest, deciduous forests also grow in layers. – The forest canopy is dominated by tall trees like: maple, oak and birch. – Small trees, shrubs and bushes abound in the understory – The forest floor gets more light than a rainforest and more plants: ferns, herbs and mosses Temperate Deciduous Forests • Temperate forest plants are adapted to survive seasonal changes • In winter, when ice locks up moisture in the soil, deciduous trees shed their leaves. Herb seeds, bulbs and underground stems become dormant underground • In the spring as sunlight increases and temperatures rise… trees put out new leaves, seeds germinate and underground stems and roots make new shoots. Temperate Deciduous Forests • Animal Adaptations: The animals are adapted to exploit the forest plants for food and shelter – Squirrels eat the nuts, seeds and fruits in the treetops – Bears feast on the leaves and sweet berries of forest plants – Deer and other browsers nibble leaves from trees and shrubs Temperate Deciduous Forests • Many birds nest in the relative safety of the canopy. • Most birds are migratory, meaning they fly south for the winter and north for the summer • Many animals (bears, insects, reptiles) become dormant (hibernate) for the winter Taiga • The taiga terrain is rough and vegetation is minimal • It is the northern coniferous forests, which is extremely cold, with average below freezing temperatures • The growing season may be as short as 50 days! Taiga • Plant Adaptations: – Conifers are trees that are evergreen, have a cone shape that helps it shed the snow, long thin needles (leaves) and include: pine, hemlock, fir and spruce – When conifers shed their needles, they release acid into the soil. Most plants can’t grow in acidic soil, so the Taiga has few plants. Blueberries, a few ferns and mosses only. Taiga • Animal Adaptations: – The taiga has many lakes and swamps that in the summer attract birds that feed on insects, fish or other wetland organisms – Many birds migrate south to avoid the winter – Some year round residents such as shrews and voles burrow underground for the winter – Moose and arctic hares eat what vegetation they can find – Predators like: Lynx, wolves and foxes change from brown in the summer to white in the winter Grasslands • Climates where there is less rainfall, forests give way to savannas, grasslands and chaparral, which in turn give way to deserts. • As precipitation decreases, so does the diversity of species present • While the number of different species if often smaller, the number of individuals of each species present can be quite large • Far to the north, another type of desert occurs, called the tundra. • Like the desert, little precipitation occurs in the tundra, but unlike the desert, temperatures stay very cold all year Savannas • Savannas contain the greatest collection of grazing animals on Earth! • Along with magnificent predators that hunt them • Savannas are found in the tropics near the equator • They get too little rain for many trees to grow Savannas Plant adaptations • Savanna trees and grasses have large underground root systems that survive fire, so plants regrow quickly after a fire • The root systems also help the plants survive during the dry season • Coarse savanna grasses have vertical leaves that help conserve water • Trees and shrubs often have thorns or sharp leaves to deter hungry herbivores Savannas Animal Adaptations: • Large grazing herbivores such as: elephants, giraffes, zebras, wildebeests and gazelles have adopted a migratory way of life, they follow the rains to areas of newly sprouted grass • Some predators such as: lions, hyenas and cheetahs, follow this mobile food source • Herbivores avoid competition by grazing on food of different heights: – Small gazelles graze on grasses – Black rhinos eat shrubs – Giraffes feed on tall tree leaves Temperate Grasslands: Prairies, Steppes and Pampas Temperate Grasslands: • Have tall grasses and little water • Have the most fertile soil of any biome on earth • Are found in the interiors of continents where there is too little rainfall for trees to grow • Mountains often play a role in maintaining grasslands (as they block the rain) • Usually only about 25cm of rainfall each year • Very hot summers, often so hot fires are common Temperate Grasslands Plant Adaptations: • Prairie grasses are perennials, meaning they survive from year to year • Their root systems form dense mats that survive drought and fire, and holds the soil in place • The amount of rainfall determines which types of grasses grow in a particular area Temperate Grasslands Animal Adaptations: • Grazing animals such as antelope and buffalo have large, flat back teeth for chewing coarse prairie grasses • Predators like wolves and coyotes feed on herbivores • Larger animals cope with severely cold winters by growing thick coats of fur • Smaller animals like badgers, prairie dogs and even owls, live in protected underground burrows Temperate Grasslands Threats: • Cultivation (farming) and overgrazing have changed grasslands • Grain crops that have replaced native grasses cannot hold the soil in place as well because their roots are shallow and soil erosion is a problem • Overgrazed grasses are constantly being chewed down and cannot grow fast enough to reproduce Chaparral • A biome that occurs in the mid-latitudes. • Mostly in costal areas • Dry hot summers and mild, wet winters with slight variations in seasonal temperature Chaparral Plant Adaptations: • Chaparral plants are mostly low lying evergreen shrubs and small trees • Common plants include: chamise, manzanita, scrub oak, olive trees and cooking herbs like sage and bay • These plants have small, leathery leaves that resist water loss Chaparral Animal Adaptations: • Camouflage is the most common adaptation of the chaparral • Animals such as the quail, lizards, chipmunks and mule deer have brownish gray coats to let them move unseen through the brush • Chaparral animals are also adapted to seasonal differences in food: the scrub jay, for example, has a beak that is adapted to eat insects, seeds and other birds eggs Chaparral Threats: • Biggest threat is human development • Because the biome has a lot of sun, access to the ocean and a mild year-round climate, people have overdeveloped almost all chaparral areas Deserts • Areas that receive less than 25cm of precipitation each year • Deserts closer to the equator are hotter than those that are not • Temperatures in the hot months can average as much 37⁰C (100⁰F) • Deserts often occur in the rain shadow of mountains that block moisture-filled clouds Deserts Plant Adaptations: • Have adaptations for obtaining and conserving water • Succulents and cacti have thick, fleshy stems and leaves that store water. They also have a waxy coating to prevent water loss • Cactus spines help deter herbivores from eating the plant’s juicy flesh Deserts Plant adaptations: • Rainfall rarely penetrates deeply into the soil, so plant roots are spread out widely just under the surface • The plants all have a survival strategy called “drought resistance”; they can live through the worse desert conditions • Some plants escape drought by dying and dropping their seeds when they die so they can re-grow during the next rain. Deserts Animal Adaptations: • Reptiles, such as Gila monsters and rattlesnakes, have thick, scaly skin that prevents water loss • Amphibians, such as the spadefoot toad, survive summers by estivating (burying themselves in the ground and sleeping through the dry season • Desert insects and spiders are covered with body armor that helps them retain water • Most desert animals are active at night when the air is cooler. Deserts Threats to Deserts: • Residential development continues to encroach upon desert areas in the American West (like Las Vegas, Nevada) • Off-road and all-terrain vehicles kill desert vegetation and destroy the habitats of endangered animals like the desert tortoise • Some desert plants are prized by collectors, who remove them from endangered plant populations Tundra • Tundra is a biome without tall trees that lies north of the Arctic Circle • The frozen tundra soil supports mostly tough grasses and shrubs • Summers are short and only the top few inches of the soil thaws; underneath is permafrost (permanently frozen soil) • Because of the permafrost, the tundra has a lot of bogs and swamps • Because of the swamps and bogs, summer time is ideal breeding grounds for insects like mosquitos and blackflies Tundra Plant Adaptations: • Mosses and lichens, which can grow without soil, covers acres of rocks in the tundra • Where soil exists it is thin, and plants have wide, shallow roots that also anchor them against arctic winds • Most flowering plants of the tundra such as the moss campion and gentian are tiny Tundra Plant Adaptations: • Being low to the ground helps plants absorb heat from the soil and prevents them form being blown over by wind • Woody plants such as the willow and juniper have evolved dwarf forms, growing flat or trailing along the ground. Tundra Animal Adaptations: • Millions of migratory birds breed in the tundra in the summer; food is abundant in the form of plants, mollusks, worms and especially insects • Caribou in N. America and reindeer in N. Europe also migrate to the tundra in the summer to breed • Hunters like wolves prey on caribou, deer, moose, lemmings, mice and rabbits Tundra Animal Adaptations: • Rodents burrow underground in the winter to survive • Arctic foxes and rabbits have fur that changes from brown in the summer to white in the winter for camouflage • Snowy owl also is white • The musk-ox has a dense shaggy coat to help it stay warm. Tundra Threats to the Tundra: • Tundra is one of the most fragile biomes on the planet • The food chains are simple and easily disrupted • Because the weather is so extreme, the land is easily damaged and slow to recover • Until recently, these areas were undisturbed by humans, but oil has been found in some tundra areas and oil drilling has a huge negative impact on the ecosystem Freshwater Ecosystems • Freshwater ecosystems include: – – – – – Lakes Ponds Rivers Streams wetlands Freshwater Ecosystems • Lakes and Ponds – In the shallow areas close to the shores of lakes and ponds, aquatic life is diverse and abundant; this area is known as the littoral zone – Further from shore, the open water that gets enough sunlight for photosynthesis is dominated by tiny plants and animals called phytoplankton and zooplankton – Some bodies of water have areas so deep there is little light for photosynthesis. This is called the benthic zone; few fish are adapted to this zone, but there are still plenty of bacteria Freshwater • Plants and animals : – Along the shore, plants such as cattails and reeds are rooted in mud, – Deeper water contains floating plants, such as pond lilies – Fish, birds, amphibians, mollusks are all common Freshwater Wetlands: • Areas of land that are covered with water for at least part of the year – Marshes are wetlands that contain non-woody plants and shrubs – Swamps are wetlands that contain woody plants and shrubs Freshwater • Wetlands are important to the environment: – They are often breeding grounds for many types of fish – They provide homes for native and migratory animals – Wetland vegetation traps carbon that would otherwise be released as carbon dioxide – Wetlands remove pollutants from the water by filtering it through the soil – They also help control flooding by giving excess water a place to go Rivers • Most rivers originate from snowmelt in mountains. This water is very cold, full of oxygen and very fast flowing • As it tumbles down the mountain, a river broadens, slows, becomes warmer and oxygen levels drop Rivers • Characteristics of rivers vary with changes in the land and climate through which it flows • Mosses are common on rocks near rivers, birds, amphibians, mammals, insects and of course hundreds of species of fish live in rivers Marine Ecosystems • The oceans of the world contain a wide variety of plant and animal communities • Types of organisms present in marine ecosystems depends on the temperature, the amount of sunlight and nutrients that are available Estuaries • An estuary is an ecosystem in which fresh water from rivers mixes with salt water from the ocean • These waters have a lot of nutrients for animals and plants to grow • There is a lot of sunlight • Typical organisms here are: oysters, clams, dolphins, manatees, seals, and plants Estuaries • The number one threat to estuaries is pollution. • Many boats use these estuaries as points to enter a river from the ocean, or enter the ocean from a river… there is a lot of boat traffic and pollution including: waste, garbage, chemical runoff, industrial waste and sewage Coral Reefs • Coral reefs are limestone islands in the sea that are built by coral animals • Thousands of species of plants and animals live in their cracks and crevices, making coral reefs among the most diverse ecosystems on earth Coral Reefs • Corals can live only in warm, salt water where there is enough light for photosynthesis • Coral reefs are found in shallow, topical seas. • Only the outer layer of a reef contains living corals, which build their rock homes with the help of photosynthetic algae Coral Reefs • Animals: because of their convoluted shape, coral reefs provide habitats for a magnificent variety of tropical fish, as well as snails, clams and sponges. There are also many predators like moray eels, sharks and groupers. Coral Reef • Threats to coral reefs– Global climate change is affecting the reefs since they are very sensitive to temperature changes – Muddy water and pollution kill the algae in the area and corals lose their food source – Oil spills, sewage, pesticide runoff are all affecting corals – Human presence, boating, ship anchors, divers are all damaging the reefs The Open Ocean • The ocean covers nearly ¾ of the earth’s surface • Although the ocean is HUGE, plants can only grow where there are nutrients and enough sunlight for photosynthesis • As a result, most of the life in the ocean is concentrated in shallow water around the edges of the continents The Open Ocean • In the open ocean, sunlight only penetrates the surface layers where phytoplankton grow if there are enough nutrients, as a result the open ocean is the least productive of all ecosystems Ocean Depths • Shallow Ocean Waters- fish are particularly abundant in coastal zones, where a rich nutrient supply washes from the land • Deep Ocean Waters- no light reaches these waters, so photosynthesis cannot occur in this area. Most of the life here depends on food that drifts down from above. Some fish have huge jaws that enable them to swallow large particles of food. Other animals of this area have lures that give off light to attract prey. Ocean Depths • The depths of the ocean are always dark and most of the food consists of dead organisms that fall from the surface called “marine snow” • There are some producers near hydrothermal vents that make food from chemosynthesis • There is no photosynthetic organisms in the deep ocean and almost all organisms in the deep are consumers Plants in the Ocean • Flowering plants are mostly absent from the ocean, except rarely around the edges near land • Food for herbivores in the open ocean is provided by phytoplankton (photosynthetic microscopic organisms) Animals in the Ocean • The sea’s smallest herbivores are zooplankton living with the phytoplankton they eat • Many open ocean fish have sleek, tapered shapes for moving though dense water • Deep ocean fish often have bioluminescence • Whales, dolphins and other marine mammals communicate with songs, clicks and barks… often using echolocation Threats to the Ocean • Although oceans are huge, they are becoming steadily more polluted by boats (especially cruise ships) and land activities that cause pollution in the rivers that runoff into the oceans • The pacific garbage patch is a floating island of garbage the size of Texas that is causing huge environmental issues in the ocean • Overfishing and net fishing are causing populations of marine life to get dangerously low. Many turtles, whales and dolphins are caught in fish nets and die. Polar Ecosystems • Ice covered polar caps at the north and south poles can be considered marine ecosystems because nearly all food is provided by phytoplankton in the ocean. Polar Ecosystems • South Pole: lies on the continent of Antarctica, where it is covered with a permanent icecap that only melts around the edges of the continent in the summer • North Pole: lies in the Arctic ocean, much of which is frozen into a huge iceberg throughout the year, with smaller icebergs drifting around the edges The Arctic • The Arctic Ocean is relatively shallow, so its waters are rich in nutrients from the surrounding landmasses and it supports a large plankton population. There fore there is a rich diversity of fish, which live in the open water and under the ice. In open waters whales and ocean birds prey on the fish. Seals are also present and the top predator of the Arctic is the polar bear The Antarctic • The Antarctic is the only continent never colonized by humans. It is governed by an international commission and is used mainly for research on the unusual animals that live there. • Even during the summer, only a few plants grow at the rocky edges of the continent. • Most food comes from plankton. This provides food for large numbers of fish, whales and birds… especially penguins. Many species of penguins breed on Antarctica Threats to Polar Ecosystems • Both the Arctic and the Antarctic contain reserves of minerals and oil, whose extraction would disrupt these largely untouched ecosystems • Conservationists want the Antarctic to be made into a wildlife refuge so that this unique ecosystem can be preserved • Tourism, especially pollution and garbage is difficult to dispose of in a climate that is too cold for decay to happen, it just stays there.