Land Biomes

1. Land Biomes APES – LCHS Dr.E

2. Introduction • Biomes are the major regional groupings of plants and animals discernible at a global scale • distribution patterns are correlated with regional climate patterns and identified according to the climax vegetation type • a biome is composed not only of the climax vegetation, but also of immature communities

3. To understand the nature of biomes one needs to learn • Global distribution pattern • Where each biome is found and how each varies geographically • A given biome may be composed of different taxa on different continents

4. To understand the nature of biomes one needs to learn • The dominant, characteristic, and unique growth forms • vertical stratification • leaf shape, size, and habit • special adaptations of the vegetation

5. To understand the nature of biomes one needs to learn • The types of animals (especially vertebrates) characteristic of the biome • Their typical morphological, physiological, and/or behavioral adaptations to the environment

6. Major Land Biomes • Tropical Rainforest • Deserts • Grasslands • Tundra

7. World Biomes Follow along with your note packet to add/modify any notes you took as you read the chapter.

8. Tropical Rainforest Location: Found near equator…little variation in temperatures. No distinct seasonal changes. http://www.cotf.edu/ete/modules/msese/earthsysflr/ Earth's most complex land biome

9. Tropical Forests • are characterized by the greatest diversity of species • occur near the equator, within the area bounded by latitudes 23.5 degrees N and 23.5 degrees S • distinct seasonality • winter is absent • only two seasons are present (rainy and dry) • The length of daylight is 12 hours and varies little.

10. Tropical Forests

11. Tropical Forests

12. Tropical Forests Temperature • average 20-25° C and varies little throughout the year • the average temperatures of the three warmest and three coldest months do not differ by more than 5 degrees

13. Tropical Forests Precipitation • evenly distributed throughout the year • annual rainfall exceeds 2 meters

14. Tropical Forests Soil • nutrient-poor and acidic • decomposition is rapid • subject to heavy leaching

15. Tropical Forests Plants • Canopy • multilayered • Continuous • allows little light penetration • Flora is highly diverse • one square kilometer may contain as many as 100 different tree species • Trees are 25-35 m tall • buttressed trunks and shallow roots • mostly evergreen, with large dark green leaves.

16. Tropical Forests Plant Adaptations • ability to tolerate constant shade • adapt strategies to reach sunlight • Fungus is a good example of a plant that flourishes in warm, dark places created by the forest canopy and understory

17. Tropical Forests Lianas Epiphytes (grow on another plant) Ferns Moss Curare Forest Canopy Palms

18. Tropical Forests White-faced Monkey Tree frog Toucan Vine Snake Gecko Vested Anteater Transparent butterfly Jaguar Unicorn grasshopper Red-eyed tree frog Silver-throated Tanager Tropical king snake Scorpion

19. Tropical Rainforest Abiotic factors • high biodiversity and biomass • both hot and moist; • ideal for bacteria and other microorganisms; they quickly decompose matter on the forest floor allowing nutrients to be recycled. • <1 cm of topsoil • About 100 in/yr of rainfall http://www.cotf.edu/ete/modules/msese/earthsysfl

20. Bougainvillea Tropical Rainforest Plant adaptations • Sunlight is a major limiting factor • Plants grow in layers (canopy receives most light) • Shallow, wide roots since soil is so thin and poor in nutrients • Little sun reaches the floor Bangul Bamboo

21. Silvery Gibbon Tropical Rainforest Animal Adaptations Many animals are specialists and require special habitat components to survive Camouflage is common • Many symbiotic relationships • Live in different levels of canopy Wagler’s pit viper Slender Loris http://www.blueplanetbiomes.org/rnfrst_animal_page.htm

22. Threats to the Tropical Rainforest Humans strip the rainforests for uses including logging and cattle ranching. In addition to the plants and animals that are displaced by this destruction, entire civilizations of people are also without a home. You can help by promoting sustainable use of the rainforests’ products http://www.blueplanetbiomes.org/rnfrst_animal_page.htm

23. Desert Ecosystems Location: Depending on type of desert, you will find them in various locations.

24. DesertAbiotic factors • <10 in/yr of rain • Little to no topsoil due to high winds. • Minerals not deep in soil. • Too dry for decay http://www.cotf.edu/ete/modules/msese/earthsysflr/taiga.html While there are many types of deserts, they all share one characteristic: They are the driest places on Earth!

25. Joshua Treehttp://www.blueplanetbiomes.org/desert_plant_page.htm Barrel Cactus Desert Plant Adaptations: • Spines • Succulents • Thick, waxy cuticle • Shallow, broad roots Ocotollio

26. Bob Cat Desert Animal Adaptations: • Get water from food • Thick outer coat • Burrow during day • Large ears • Smaller animals = less surface area http://www.blueplanetbiomes.org/desert_animal_page.htm Armadillo Lizard Javelina

27. http://www.blueplanetbiomes.org/world_biomes.htm Threats to the Desert Residential development Off road recreational activities destroy habitat for plants and animals. Some plants are removed by collectors, endangering the population. Dry Desert Sonoran Desert

28. Deserts • Deserts cover about one fifth of the Earth’s surface and occur where rainfall is less than 50 cm/year • Most deserts occur at low latitudes • Another kind of desert, cold deserts, occur in the basin and mountain ranges • Most deserts have a considerable amount of specialized vegetation, as well as specialized vertebrate and invertebrate animals

29. Deserts • Soils often have abundant nutrients because they need only water to become very productive and have little or no organic matter • Disturbances are common in the form of occasional fires or cold weather, and sudden, infrequent, but intense rains that cause flooding

32. Types of Deserts • Hot and Dry • Semiarid • Coastal • Cold

33. Hot and Dry Desert Temperature • Desert surfaces receive a little more than twice the solar radiation received by humid regions and lose almost twice as much heat at night • Many mean annual temperatures range from 20-25° C • The extreme maximum ranges from 43.5-49° C. Minimum temperatures sometimes drop to -18° C

34. Hot and Dry Desert Precipitation • Rainfall is usually very low and/or concentrated in short bursts between long rainless periods • Evaporation rates regularly exceed rainfall rates • Sometimes rain starts falling and evaporates before reaching the ground • Rainfall is lowest on the Atacama Desert of Chile, where it averages less than 1.5 cm • Inland Sahara also receives less than 1.5 cm a year • Rainfall in American deserts is higher—almost 28 cm a year

35. Hot and Dry Desert Soils • Soils are course-textured, shallow, rocky or gravely with good drainage and have no subsurface water • They are coarse because there is less chemical weathering • The finer dust and sand particles are blown elsewhere, leaving heavier pieces behind

36. Hot and Dry Desert Plants • Canopy in most deserts is very rare • Plants are mainly ground-hugging shrubs and short woody trees • Leaves are “replete” (fully supported with nutrients) with water-conserving characteristics • They tend to be small, thick and covered with a thick cuticle (outer layer) • In the cacti, the leaves are much-reduced (to spines) and photosynthetic activity is restricted to the stems • Some plants open their stomata (microscopic openings in the epidermis of leaves that allow for gas exchange) only at night when evaporation rates are lowest

37. Hot and Dry Desert Yuccas Ocotillo Turpentine bush Prickly Pears False mesquite Sotol Ephedras Agaves Brittlebush

38. Hot and Dry Desert Animals • The animals include small nocturnal (active at night) carnivores • The dominant animals are burrowers and kangaroo rats • There are also insects, arachnids, reptiles and birds • The animals stay inactive in protected hideaways during the hot day and come out to forage at dusk, dawn or at night, when the desert is cooler

39. Snakes Lizards TortoiseBighorn Sheep CoyoteAnts TarantulaTarantula Wasp

40. Semiarid Desert Temperature • The summers are moderately long and dry, and like hot deserts, the winters normally bring low concentrations of rainfall • Summer temperatures usually average between 21-27° C • It normally does not go above 38° C and evening temperatures are cool, at around 10° C.

41. Semiarid Desert Precipitation • Cool nights help both plants and animals by reducing moisture loss from transpiration, sweating and breathing • Condensation of dew caused by night cooling may equal or exceed the rainfall received by some deserts • As in the hot desert, rainfall is often very low and/or concentrated • The average rainfall ranges from 2-4 cm annually.

42. Semiarid Desert Soils • ranges from sandy and fine-textured to loose rock fragments, gravel or sand • fairly low salt concentration, compared to deserts which receive a lot of rain (acquiring higher salt concentrations as a result) • there is no subsurface water.

43. Semiarid Desert Plants • The spiny nature of many plants in semiarid deserts provides protection in a hazardous environment • The large numbers of spines shade the surface enough to significantly reduce transpiration • The same may be true of the hairs on the woolly desert plants • Many plants have silvery or glossy leaves, allowing them to reflect more radiant energy • These plants often have an unfavorable odor or taste.

44. Semiarid Desert Creosote bush Bur sage White thorn Cat claw Mesquite Brittle bushes Lyciums Jujube

45. Semiarid Desert Animals • During the day, insects move around twigs to stay on the shady side; jack rabbits follow the moving shadow of a cactus or shrub • Naturally, many animals find protection in underground burrows where they are insulated from both heat and aridity

46. Semiarid Desert Kangaroo rats Rabbits Skunks Side-blotched Lizard Mountain Lion Mule Deer Rattlesnake Burrowing owls Western Bluebird

47. Coastal Desert Temperature • The cool winters of coastal deserts are followed by moderately long, warm summers • The average summer temperature ranges from 13-24° C; winter temperatures are 5° C or below • The maximum annual temperature is about 35° C and the minimum is about -4° C • In Chile, the temperature ranges from -2 to 5° C in July and 21-25° C in January

48. Coastal Desert Precipitation • The average rainfall measures 8-13 cm in many areas • The maximum annual precipitation over a long period of years has been 37 cm with a minimum of 5 cm

49. Coastal Desert Soils • fine-textured with a moderate salt content • fairly porous with good drainage.

50. Coastal Desert Plants • extensive root systems close to the surface where they can take advantage of any rain showers • thick and fleshy leaves or stems can take in large quantities of water when it is available and store it for future use • some surfaces are corrugated with longitudinal ridges and grooves • stem swells so that the grooves are shallow and the ridges far apart • the stem shrinks as water is used so that the grooves are deep and ridges close together.