Biomes (communities on a global scale).pptx

Biomes as large-scale ecological units defined by vegetation, climate, and geography.

Factors influencing biomes: Climate (temperature and precipitation), latitude, altitude, and soil type.

Biotic and abiotic components: Interaction between living organisms and their physical environment.

1. Biomes (communities on a global scale) Dr. Vividha Raunekar

2. A biome is a large area of the Earth or ocean with a similar climate, landscape, and plant and animal life biosphere, relatively thin life-supporting stratum of Earth's surface, extending from a few kilometres into the atmosphere to the deep-sea vents of the ocean . An ecosystem is a community of organisms and their physical environment interacting together . Environment involves both living organisms and the non-living physical conditions. In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area at the same time A population is a group of the same species living in the same area.

3. Introduction to Biomes Definition: Biomes as large-scale ecological units defined by vegetation, climate, and geography. Factors influencing biomes: Climate (temperature and precipitation), latitude, altitude, and soil type. Biotic and abiotic components: Interaction between living organisms and their physical environment.

4. Tropical Rainforests Location : Near the equator, including the Amazon Basin (South America), Congo Basin (Africa), and Southeast Asia. Climate : High temperature (20–30°C) year-round. High rainfall (over 2000 mm annually). Characteristics : Dense, multilayered vegetation with a closed canopy. High biodiversity (e.g., jaguars, tucans , orchids, bromeliads). Threats : Deforestation for agriculture, logging, and urbanization.

5. Savannas Location : Africa (e.g., Serengeti), South America, and Australia. Climate : Warm temperatures (20–30°C). Seasonal rainfall (500–1500 mm annually), with distinct wet and dry seasons. Characteristics : Grasses dominate, with scattered trees like acacias and baobabs. Large herbivores (e.g., elephants, giraffes) and predators (e.g., lions, cheetahs). Threats : Overgrazing, agriculture, and climate change.

6. Deserts Location : Sahara (Africa), Gobi (Asia), Mojave (North America), Atacama (South America). Climate : Extreme temperature variations (hot deserts: 30–50°C during the day, cold deserts: below freezing). Low precipitation (less than 250 mm annually). Characteristics : Sparse vegetation (cacti, succulents). Animals adapted to conserve water (e.g., camels, fennec foxes). Threats : Desertification due to overuse of land and water resources.

7. Temperate Grasslands Location : Prairies (North America) Prairies are enormous stretches of flat grassland with moderate temperatures, moderate rainfall, and few trees. , steppes (Eurasia), pampas (South America). Climate : Moderate temperatures (0–25°C). Rainfall ranges from 250–750 mm annually. Characteristics : Dominated by grasses with few trees. Support grazing animals like bison and antelope. Threats : Conversion to agricultural land and overgrazing.

8. Temperate Deciduous Forests Location : Eastern North America, Europe, East Asia. Climate : Four distinct seasons. Moderate rainfall (750–1500 mm annually). Characteristics : Trees lose leaves in autumn (e.g., oaks, maples). Diverse fauna, including deer, foxes, and migratory birds. Threats : Logging, habitat fragmentation, and urban sprawl.

9. Boreal Forests (Taiga) Location : Canada, Russia, Scandinavia. Climate : Long, cold winters and short, mild summers. Moderate precipitation (300–850 mm annually, mostly as snow). Characteristics : Evergreen conifers like spruce, fir, and pine. Animals adapted to cold (e.g., lynx, moose, wolves). Threats : Logging, mining, and climate change. Wild elk in boreal forest, Banff National Park

10. Tundra Location : Arctic regions (Alaska, Canada, Siberia) and alpine zones. Climate : Cold temperatures (-30°C to 10°C). Low precipitation (150–250 mm annually). Characteristics : Permafrost underlies soil, limiting plant growth. Mosses, lichens, and low shrubs dominate. Fauna includes caribou, arctic foxes, and polar bears. Threats : Melting permafrost, oil exploration, and habitat loss.

11. Mediterranean (Chaparral) Location : Mediterranean Basin, California, Chile, South Africa, Australia. Climate : Mild, wet winters and hot, dry summers. Rainfall ranges from 300–600 mm annually. Characteristics : Vegetation adapted to drought and fire (e.g., shrubs, olive trees). Fauna includes small mammals, reptiles, and birds. Threats : Urbanization and wildfires.

12. Freshwater Biomes Location : Rivers, lakes, wetlands worldwide. Characteristics : Support diverse aquatic plants, fish and amphibians. Crucial for drinking water, agriculture, and biodiversity. Threats : Pollution, eutrophication, and overfishing.

13. Marine Biomes Location : Oceans, coral reefs, and estuaries. Characteristics : Cover 70% of Earth’s surface. Coral reefs host immense biodiversity. Marine life includes phytoplankton, fish, whales, and sharks. Threats : Overfishing, coral bleaching, and ocean acidification.

14. Climate and Biome Distribution Key Points: How climate determines biome distribution: Role of temperature and precipitation. Seasonal variations and their impacts on biodiversity. Correlation between latitude, altitude, and biome diversity (e.g., from equator to poles; from base to summit of mountains). Example: Comparison of temperate grasslands and tropical rainforests.

15. Human Impacts on Biomes Key Points: Habitat destruction, urbanization, and land-use changes. Climate change and its differential impact on biomes (e.g., coral bleaching in marine systems, tundra thawing). Conservation strategies: Protected areas (e.g., national parks, marine reserves). Restoration ecology. Examples: Deforestation rates. Effects of melting Arctic ice on global sea levels.

16. Case Study Analysis : Group discussion- Wildfire in Los Angeles

17. Thank you