Climate and Terrestrial Biodiversity

1. Climate and Terrestrial Biodiversity Chapter 6 (Biomes: Sections 3-7)

2. Key Concept 1: How Does Climate Affect the Nature and Locations of Biomes? • 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.

3. Climate Affects Where Organisms Can Live • Major biomes • Similar climate, soil, plants, animals throughout world • Ecotone • Latitude and elevation • Annual precipitation • Deserts, grasslands, forests • Temperature • Tropical, temperate, polar

4. The Earth’s Major Biomes

5. Generalized Effects of Elevation and Latitude on Climate and Biomes

6. Cold Polar Tundra Subpolar Temperate Coniferous forest Decreasing temperature Desert Grassland Deciduous forest Tropical Chaparral Hot Desert Savanna Rain forest Wet Dry Tropical seasonal forest Scrubland Decreasing precipitation Fig. 7-10, p. 147

7. There Are Three Major Types of Deserts • Tropical deserts • Temperate deserts • Cold deserts • Fragile ecosystems • Hundreds of years for soil to recover from disturbances • Slow plant growth • Low species diversity • Slow nutrient recycling (Why?) • Lack of water

8. Climatographs of 3 Types of Deserts

9. Staying Alive in the Desert • Plant adaptations • Drop leaves or no leaves • Storage of water and food in fleshy tissue • Take in CO2 only at night • Deep roots to tap into ground water • Waxy coating on leaves • Animal strategies and adaptations • Small, hide during the day • Dormant • Camel – stores massive amounts of water, doesn’t sweat • Don’t drink – water from break down of fats in seeds • Think coverings • Dry feces and urine

10. There Are Three Major Types of Grasslands • Tropical • Savanna • Grazing animals • Browsing animals • Temperate • Tall-grass prairies • Short-grass prairies

11. There Are Three Major Types of Grasslands • Cold (arctic tundra) – treeless plains • Can be referred to as desert • Fragile biome • Nutrient poor soil • Melting of permafrost • Release CH4 and CO2 into the atmosphere • Adaptations of plants and animals • Thick fur or feathers • Living underground • Low growing plants • Alpine tundra – below permafrost snow line on mountains, more sunlight, more flowers

12. Climatographs of Tropical, Temperate, and Cold Grasslands

13. Temperate Shrubland: Nice Climate, Risky Place to Live • Chaparral • Near the sea: nice climate • Significant human impact • Prone to fires in the dry season • Maintained by fire, plants adapt with fire-resistant roots, produce seeds that sprout after fire, use nutrients released by the fire • Soil thin and not very fertile

14. Chaparral Vegetation in Utah, U.S.

15. There Are Three Major Types of Forests (Dominated by Trees) • TROPICAL • Tropical rain forests • Warm temperatures, high humidity, heavy rainfall • Dominated by broadleaf evergreen plants • Stratification of specialized plant and animal niches • Emergent layer, canopy (most life forms), understory, shrub layer, ground level • Little wind to spread seeds, depend on pollinators • Rapid recycling of scarce soil nutrients due to warm, moist conditions • Immediately taken up by trees, poor soil • Impact of human activities?

16. There Are Three Major Types of Forests • TEMPERATE • Temperate deciduous forests • Moderate temperatures, abundant precipitation • Dominated by few species of broad-leaf trees • Drop leaves and become dormant in winter • Slow rate of decomposition: storehouse of nutrients • Impact of human activities more than any other biome

17. There Are Three Major Types of Forests • COLD • Evergreen/Northern coniferous forests: boreal and taigas • Long extremely cold and dry winters • Few species of cone-bearing evergreen trees • Low plant diversity • Slow decomposition: waxy coating on needles, acidic soil, nutrient poor • Coastal coniferous forest/Temperate rain forests • Ample rainfall or moisture from dense ocean fog

18. Climatographs of Tropical, Temperate, and Cold Forests

19. Stratification of Specialized Plant and Animal Niches in a Tropical Rain Forest

20. Mountains Play Important Ecological Roles • Dramatic changes in altitude, slope, climate, soil, and vegetation • Majority of the world’s forests • Majority of world’s terrestrial biodiversity • Habitats for endemic species • Sanctuaries for migrating animals (low to high) • Help regulate the earth’s climate • Ice and snow reflect solar radiation back into space • Opposite – dark exposed rock absorbs energy? • Can affect sea levels • Major storehouses of water - role in hydrologic cycle

21. Key Concept 2: How Have We Affected the Word’s Terrestrial Ecosystems? • In many areas, human activities are impairing ecological and economic services provided by the earth’s deserts, grasslands, forests, and mountains.

22. NATURAL CAPITAL DEGRADATION Major Human Impacts on Terrestrial Ecosystems Mountains Forests Grasslands Deserts Clearing for agriculture, livestock grazing, timber, and urban development Large desert cities Conversion to cropland Agriculture Timber extraction Soil destruction by off-road vehicles Release of CO2 to atmosphere from burning grassland Mineral extraction Hydroelectric dams and reservoirs Soil salinization from irrigation Conversion of diverse forests to tree plantations Increasing tourism Overgrazing by livestock Depletion of groundwater Urban air pollution Increased ultraviolet radiation from ozone depletion Damage from off-road vehicles Oil production and off-road vehicles in arctic tundra Land disturbance and pollution from mineral extraction Pollution of forest streams Soil damage from off-road vehicles Fig. 7-20, p. 158