ES LECTURE 8: World Biomes PDF

ES LECTURE 8: World Biomes WESLEYAN UNIVERSITY-PHILIPPINES College of Arts and Sciences Prepared by: DIVINE GRACE S. BATENGA, MSc. Department of Science and Mathematics...

ES LECTURE 8: World Biomes WESLEYAN UNIVERSITY-PHILIPPINES College of Arts and Sciences Prepared by: DIVINE GRACE S. BATENGA, MSc. Department of Science and Mathematics 1 BIOMES AND CLIMATE Desert in Africa Rainforest in Australia What is the most obvious difference between the two places? What causes these two places to be so different? 2 What is Climate? Climate is the average weather in an area over a long period of time, whereas weather is a day to day explanation. Weather and climate are described in terms of factors such as temperature and precipitation. The climate of a particular location depends, in turn, on its latitude (distance from the equator) and altitude (distance above sea level). Other factors that affect an area’s climate include its location relative to the ocean or mountain ranges. Temperature and moisture are the two climatic factors that most affect terrestrial biomes. 3 What effect do mountains have on surrounding land? 4 BIOMES A biome is an area of the planet that can be classified according to the plants and animals that live in it. ▪ Temperature, soil, and the amount of light and water help determine what life exists in a biome. A biome is different from an ecosystem. ▪ An ecosystem is the interaction of living and nonliving things in an environment. ▪ A biome is a specific geographic area notable for the species living there. ▪ A biome can be made up of many ecosystems. 5 Fundamental Classification of Biomes ❑ TERRESTRIAL (land) BIOMES ▪ Desert ▪ Forest ▪ Grassland ▪ Tundra ❑ AQUATIC BIOMES ▪ Freshwater biomes ▪ Saltwater biomes (marine) 6 BIOMES OF THE WORLD 7 TERRESTRIAL BIOMES 8 TERRESTRIAL BIOMES Latitudinal patterns of climate over the Earth’s surface--- latitudinal patterns of biome distribution Most terrestrial biomes are named for major physical or climatic features (predominant vegetation) The species composition of any biome differs from location to location. Human activity has radically altered the natural patterns of periodic physical disturbance. Humans have altered much of the Earth’s surface, replacing original biomes with urban or agricultural ones. 9 Tropical Forests Found close to the equator. Tropical rain forests receive constant high amounts of rainfall (200-400 cm annually). In tropical dry forests, precipitation is Tropical rain forest highly seasonal. In both, air temperatures range between 25°C and 29°C year round. Tropical forests are stratified, and competition for light is intense. Animal diversity is higher in tropical forests than in any other terrestrial biome. Tropical dry forest 10 Tropical Forests Tropical Rain Forests The forest biome which is characterized by high temperature and moist habitat. Seasonality: wet and dry season (winter is absent) The length of daylight is 12 hours Precipitation is evenly distributed throughout the year with annual rainfall exceeding to 2000 mm 11 Tropical Forests Tropical Rain Forests Highest animal diversity Highest plant diversity 12 Tropical Forests Tropical Rain Forests Soil is nutrient-poor and acidic Decomposition of products are immediately taken up by plant extensive root system 13 Tropical Forests Tropical Rain Forests Sunlight is a limiting factor Canopy in tropical forests is multilayered and continuous, allowing little light penetration 14 15 Tropical Forests Tropical Dry Forests Short dry period in a very wet tropical region 16 17 DESERTS An ecosystem that forms due to low level of rainfall it receives each year. Deserts have low and highly variable rainfall, generally less than 30 cm per year. Temperature varies greatly seasonally and daily. 18 DESERTS FACTS ABOUT DESERT BIOME 19 DESERTS HOW ARE DESERTS CLASSIFIED? Deserts are classified on how Cold Desert much rain-fall the area receives per year If it receives under 254 mm per Hot Desert year it is classified as a desert 2 types of desert: hot and cold 20 DESERTS COLD DESERT Average annual rainfall: