Biomes n A major type of ecosystem with
Biomes n. A major type of ecosystem with distinctive temperature, rainfall, and organisms.
6 Types of Biomes 1. Deserts 2. Tundras 3. Grasslands 4. Forests 5. Freshwater 6. Marine
Biomes n Blue Planet Biomes World Biomes
7. 1 Deserts *They have different characteristics depending where they are in the world *Home to different organisms *Receive very little rain. This is a limiting factor *Soils are rich in minerals but poor in organic material
Leaching *When rainwater that moves through the soil carries minerals deeper into the soil. *Since there is little rainfall in the desert, there is little leaching. *As a result, the upper part of the soil is rich in minerals *Since little rainfall, there is lack of organic material, which is able to decay. This decayed organic material is important in topsoil, so there is hardly any desert topsoil
Pavement *This is the desert floor *Made of hard baked sand, bare rocks or both *This is due to wind blowing the loose, dry soil away
Two Types of Deserts Hot deserts Cool Deserts n Located between the Sierra Nevadas and Rocky Mountains. Found on eastern sides of western mountains. n Located in the southwest, particularly California, Arizona, New Mexico and western Texas
Desert Climate *10 - 25 cm (about 10 inches) or less of precipitation per year * This determines the types of plants which determine the types of animals *Rain usually falls during a short thunderstorm followed by a long period of dry weather *Since the desert pavement is dry, most of the rain runs off and is not absorbed *Lack of rain causes a lack of moisture. This affects the temperature of the desert. There is no blanket to absorb heat and hold in the warmth *Desert has hot, hot days and cold nights
Desert Organisms *Adapted to survive two challenges. 1. Lack of water 2. Extreme temperatures *Adaptations include behavior and structural changes.
Desert Plants · Provide base of food web, so determine types of animals which live in the desert · Few plants survive because climate is too dry n Must be able to absorb water from the ground
Desert Plants *Must be able to prevent loss of water from their tissues *Cacti are examples, they are called succulents. *Spines are modified leaves *They are able to store water for dry times *Their spines also protect them against predators, which eat them *Aloe Vera is native to Africa (not related to cacti) *Some other plants have roots that are long and extend a long distance to get water. An example is the mesquite tree. *Sagebrush is another example
Desert Plants
Desert Animals * Has many animals * Insects, reptiles, birds and mammals * Get most of their water from plants *All animals have an outer coat that reduces water loss * Have adaptations to survive heat * Kangaroo rat is an example * Spend day in underground burrows and come out at night when it is cooler *These animals are known as nocturnal animals
Desert Animals
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