Transcript Deserts
Biome Project – Nathalie, Chelsey & Jessica DESERTS DESERTS AROUND THE WORLD CLIMATE Deserts are all dry and have a lack of water but they are not all hot. Some deserts, depending on their location can be cold. These deserts are usually found in high latitudes and higher elevations. They usually lie between the subtropical and polar regions. Many hot deserts are found in the subtropical zones. The Sahara Desert is the world’s largest desert and during the day temperatures normally reach over 38°C but at night it can fall bellow zero. Hot and cold deserts, no matter where they are, are always dry. Arid regions are characterized by having less than 20 inches of rain per year. Although, most deserts only receive 10 inches per year. DEFINING FEATURES Sparse, rare rainfall. Drought-adapted plants and animals. Plants rely on conservation of moisture and energy in the dry desert. Others lose their leaves when temperatures become too intense. When the short rain season comes, plants burst into color, sprouting their leaves and flowers. Many large cacti, store amounts of water in their thick stems. Plants slow down their growth for half a year to help use less water, food, and energy during hot seasons PLANT ADAPTATIONS A large number of desert plants start off as seeds. Seeds can survive without water for indefinite periods of time. After the rain washes away the anti-sprouting chemical from it’s shell, the seed may then sprout when the temperature is moderate. When these plants sprout they may not live very long, because many desert plants sprout, mature, flower, and then die in a very short period of time. Animals need to regulate their body temperature during the day and at night. Mammals and birds body heat remains stable as long as they are not in the heat for long periods of time. During the cold desert nights, they remain warm as long as they’ve eaten enough food to produce energy. Reptiles and amphibians have no way of controlling their body heat. They control their temperature by either sitting out in the sun or staying in the shade. ANIMAL ADAPTATIONS Quite a few of the animals that live in the deserts get water from what they eat. Roadrunners, for example, get their water from lizards, insects, small snakes, and other animals. Tortoises get their water from cacti and other plants. Storing water is necessary for its survival. It has two water saving cabins under its shell that holds water it gets from the cacti it eats. Surprisingly, fish also live in the desert. They live in springs and small rivers. In Death Valley National Monument, located in Nevada, a few hundred Devil's Hole pupfish live above a limestone shelf in a spring hole. This spring hole is only 25 square meters. All the pupfish members breed and carry out their whole life in this tiny spring hole. Mining Tourism Farming Ranching Drilling operations