Climate and Biodiversity Chapter 5
5-2 How Does Climate Affect the Nature and Location of Biomes? Concept 5-2 Differences in average annual precipitation and temperature lead to the formation of tropical, temperate, and cold deserts, grasslands, and forests, and largely determine their locations.
Climate Affects Biomes Major biomes related to climate Biomes consist of a mosaic of patches of communities Average temperature and precipitation determine the biome
Earth’s Major Biomes Fig. 5-8, p. 81
Correlation Between Latitude and Elevation
(herbs, lichens, mosses) Elevation Mountain ice and snow Tundra (herbs, lichens, mosses) Coniferous Forest Latitude Deciduous Forest Tropical Forest Figure 5.9: Generalized effects of elevation (left) and latitude (right) on climate and biomes. Parallel changes in vegetation type occur when we travel from the equator to the poles or from lowlands to mountaintops. Tropical Forest Deciduous Forest Coniferous Forest Tundra (herbs, lichens, mosses) Polar ice and snow Fig. 5-9, p. 81
Climate Determines the Biome
Deciduous forest Tropical seasonal forest Polar Tundra Subpolar Temperate Coniferous forest Desert Deciduous forest Grassland Tropical Chaparral Figure 5.10: Natural capital: average precipitation and average temperature, acting together as limiting factors over a long period of time, help to determine the type of desert, grassland, or forest biome in a particular area. Although each actual situation is much more complex, this simplified diagram explains how climate helps to determine the types and amounts of natural vegetation found in an area left undisturbed by human activities. (Used by permission of Macmillan Publishing Company, from Derek Elsom, The Earth, New York: Macmillan, 1992. Copyright © 1992 by Marshall Editions Developments Limited) Desert Savanna Rain forest Tropical seasonal forest Scrubland Fig. 5-10, p. 82
Three Major Types of Deserts Tropical deserts – Sahara, Namib Temperate deserts – Mojave Cold deserts – Gobi
Climate Graph of Tropical United Arab Emirates Desert
Climate Graph of Temperate Arizona Desert
Climate Graph of Cold Gobi Desert
Figure 5.11: Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold deserts. Top photo: a popular (but destructive) SUV rodeo in United Arab Emirates (tropical desert). Center photo: saguaro cactus in the U.S. state of Arizona (temperate desert). Bottom photo: a Bactrian camel in Mongolia’s Gobi (cold) desert. Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of deserts? Fig. 5-11, p. 83
Science Focus: Staying Alive in the Desert Desert survival Beat the heat Conserve water Plants have evolved survival strategies Animals have own special adaptations
Three Major Types of Grasslands Tropical grasslands – savanna Temperate grasslands – prairie Short-grass vs. tall-grass Cold grasslands – tundra Permafrost soils
Savanna Grassland
Montana Prairie Grassland
Arctic Tundra Grassland
Figure 5.12: Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold (arctic tundra) grasslands. Top photo: wildebeests grazing on a savanna in Maasai Mara National Park in Kenya, Africa (tropical grassland). Center photo: wildflowers in bloom on a prairie near East Glacier Park in the U.S. state of Montana (temperate grassland). Bottom photo: arctic tundra with caribou in Alaska’s Arctic National Wildlife Refuge (cold grassland). Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of grassland? Fig. 5-12, p. 85
Loss of a Temperate Grassland Fig. 5-13, p. 86
Three Major Types of Forests Tropical rain forests Temperate deciduous forests Evergreen coniferous forests
Tropical Forest
Temperate Deciduous Forest
Evergreen Coniferous Forest
Figure 5.14: Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold (northern coniferous and boreal) forests. Top photo: the closed canopy of a tropical rain forest in the western Congo Basin of Gabon, Africa. Middle photo: a temperate deciduous forest in the U.S. state of Rhode Island during the fall. (Photo 4 on p. vii shows this same area of forest during winter.) Bottom photo: a northern coniferous forest in the Malheur National Forest and Strawberry Mountain Wilderness in the U.S. state of Oregon. Question: What months of the year have the highest temperature and the lowest rainfall for each type of forest? Fig. 5-14, p. 87
Tropical Rain Forest Ecosystem
Ocelot Blue and gold macaw Harpy eagle Squirrel monkeys Climbing monstera palm Katydid Slaty-tailed trogon Green tree snake Tree frog Figure 5.15: Some components and interactions in a tropical rain forest ecosystem. When these organisms die, decomposers break down their organic matter into minerals that plants use. Colored arrows indicate transfers of matter and energy between producers; primary consumers (herbivores); secondary, or higher-level, consumers (carnivores); and decomposers. Organisms are not drawn to scale. See an animation based on this figure at ThomsonNOW. Ants Bacteria Bromeliad Fungi Producer to primary consumer Primary to secondary consumer Secondary to higher-level consumer All producers and consumers to decomposers Fig. 5-15, p. 88
Stratification of Tropical Rain Forest
Brazilian tapir Black-crowned antpitta Emergent layer Harpy eagle Toco toucan Canopy Under story Wooly opossum Figure 5.16: Stratification of specialized plant and animal niches in a tropical rain forest. Filling such specialized niches enables species to avoid or minimize competition for resources and results in the coexistence of a great variety of species. Brazilian tapir Shrub layer Black-crowned antpitta Ground layer Fig. 5-16, p. 89
Importance of Mountains Contain majority of the world’s forests Regulate climate Key in the hydrological cycle