Melinda Weaver. Searching the Savanna. Biome Map Worksheet. Biome Matching Game Worksheet. By volunteering, or simply sending us feedback on the site. Scientists, teachers, writers, illustrators, and translators are all important to the program. If you are interested in helping with the website we have a Volunteers page to get the process started. Digging Deeper.
Digging Deeper: Depression and the Past. Digging Deeper: Germs and Disease. Digging Deeper: Milk and Immunity. How Do We See? How Do We Sense Smell? How Do We Sense Taste? How Do We Sense Touch? What is Evolutionary Medicine? What's a Biologist? What's a GMO? What's a Genome? Transitional: a state or characteristic of something that is changing. Vegetation: plant life, usually in a certain area. View Citation You may need to edit author's name to meet the style formats, which are in most cases "Last name, First name.
Modern Language Association, 7th Ed. The Serengeti of Africa is one of the most well-known savannas. Quiz Yourself. Two groups of plants that are pre-adapted to survive fire become dominant in areas where burning is frequent and periodic. Such fires have both natural and human origins. The savannas of South east Asia are generally considered to be man-made. Palms have the advantage of being monocots: their vascular bundles are scattered throughout the stem so that scorching of the outermost layer of the trunk will not kill the plant.
Dicot trees, on the other hand, have their vascular bundles arrnaged around the outer, living part of their stems where they may be easily destroyed by fire. Perennial grasses have underground stems or rhizomes and so their growth nodes are protected by the soil during a ground fire. Trees and shrubs—with renewal buds above the surface—are selected against by fire and the balance tips toward the grasses.
Grazing subclimax. Large mammals such as the elephant open woodlands by debarking the trees and by knocking them over. This opens the woodland to grass invasion and attracts a variety of grazing animals, including zebras, wildebeest, and the diverse antelopes of the Ethiopian province. Grazers will both eat and trample tree seedlings, inhibiting the regrowth of the woodland.
Only well-armed species of shrubs and trees can establish themselves in the clearings, leading to thickets of thorny acacias. Protected in the thicket, some acacias and other thorny trees will grow to mature specimens.
Overgrazing: if a grass savanna is overgrazed, patches of bare ground will be created. The grassland will not longer carry a ground fire and invasion by trees becomes possible. The bare ground will suffer from increased evaporation and a dry microhabitat quickly develops.
Well-armed, drought-resistant species like the acacias tolerate both grazing and drought, so again an acacia savanna can become established. The antelopes are especially diverse and including eland, impalas, gazelles oryx, gerenuk, and kudu. Buffalo, wildebeest, plains zebra, rhinos, giraffes, elephants, and warthogs are among other herbivores of the African savanna.
Up to sixteen grazing and browsing species may coexist in the same area. The species-rich herbivore trophic level supports a diverse set of carnivores, including cats lions, leopards, cheetahs, servals , dogs jackals, wild dogs , and hyenas.
Most herbivorous mammals of the open savannas are herd animals, often organized into groups of females and their young with a single dominant male and groups of bachelor males. In South America a distinct savanna fauna is not well-developed. The capybara, the large semi-aquatic rodent, is associated with the llanos, but is found elsewhere and in other vegetation types as well. These are tolerant of the annual drought and usually highly resilient to burning, at least when mature.
Savanna grasses include annuals and perennials, and both types have short, intense growing periods during the Wet season, then either die or dry off to the roots during the Dry. Many grasses respond positively to fire, resprouting rapidly after burning.
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