Desert Ecology is the study of the interaction between biotic and abiotic components in the desert environment. Desert ecosystems are defined by the interactions between the population of the organism, the climate in which they live, and other non-living influences in the habitat. The desert is a dry area with generally associated with warm temperatures, but a cold desert also exists. Deserts can be found on every continent, with the largest being in Antarctica, the Arctic, North Africa, and the Middle East.
Video Desert ecology
Climate
The desert experiences various temperatures and weather conditions. They can be classified into four types: hot, semi-arid, coastal, and cold. Hot desert has warm temperatures at any time of the year, and low annual rainfall. The lack of moisture in the desert produces high temperatures during the day and a large amount of heat loss at night. Although the annual average temperature in the hot desert is 20 Â ° C to 25 Â ° C, extreme weather conditions can cause temperatures from -18 Â ° C to 49 Â ° C. Rainfall generally occurs in concentrated bursts, followed by long periods without precipitation. Semiarid desert experiences conditions similar to hot deserts, but maximum and minimum temperatures tend to be less extreme, ranging from 10 ° C to 38 ° C. Coastal Desert cooler than hot and semi-arid deserts, with average summer temperatures between 13 ° C and 24 ° C. They also display higher total rainfall values. The cold desert has the same temperature as the desert on the beach, but they receive more rainfall every year, which is mostly snow. The deserts are most important for their dry climates resulting from the rain-blocking mountains and the remoteness of the moisture of the oceans. The desert occupies one fifth of the Earth's land surface and occurs in two belts: between 15 Â ° and 35 Â ° latitude in both southern and northern hemispheres. These bands are associated with high solar intensity received by all regions of the tropics, and at the same time with dry air brought down by Hadley and Ferell's arms that destroy atmospheric circulation cells.
Desert generally occurs due to global wind patterns or rain shadows. Dry winds not only retain a little moisture for this area, but also tend to evaporate existing water. The shadow of rain does not occur because of the general wind pattern, but because of the wind that passes through the mountains. As the air rises and cools, its relative humidity increases and some or most of the rain falls, leaving little or no moisture to form precipitation on the other side of the mountains.
Many desert ecosystems are limited by available water levels, rather than radiation or temperature levels. The flow of water in this ecosystem can be considered the same as the flow of energy; in fact, it is often useful to see the flow of water and energy together when studying ecosystems and ecology of the desert.
The availability of water in the desert can also be hindered by loose sediments. Dust clouds usually form in windy and windy climates. Scientists previously theorized that clouds of desert dust would increase rainfall, but several studies have shown that deposition is actually hampered by this phenomenon by absorbing moisture from the atmosphere. This absorption can generate positive feedback, leading to further desertification.
Maps Desert ecology
Landscape
The desert landscape can contain many geological features, such as oases, rock outcrops, sand dunes, and mountains. The dune is a structure formed by the sediment of the wind moving into the mound. Sand dunes are generally classified based on their orientation relative to the wind directly. Perhaps the most recognizable type of dune is the transverse hill, which crosses into the wind. Many dunes are considered active, meaning that they travel and change over time due to the influence of the wind. However, some dunes can be anchored in place by vegetation or topography, preventing their movement. Some dunes can also be called sticky, which occurs when individual grains of sand are cemented together. Curved sand dunes tend to be more stable and resistant to wind rework than the loose sand dunes.
Analysis of geological features in desert environments can reveal much about the history of the area. Through the observation and identification of rock deposits, geologists were able to interpret the sequence of events occurring during the formation of the desert. For example, research conducted on the surface geology of the Namib Desert allows geologists to interpret the ancient River Kuiseb movement based on rock age and features identified in the area.
Organic Adaptation
Animal
The desert supports a diverse community of plants and animals that have evolved resistance to, and methods to avoid, extreme temperatures and dry conditions. For example, desert pastures are more humid and slightly colder than the surrounding ecosystems. Many animals get their energy by eating plants, but desert plants hand over their production fruits with great reluctance. To avoid high temperatures, most of the small desert mammals are nocturnal, and dig their burrows. These holes help to keep it from overheating and result in water loss, and to keep the mammalian optimal temperature. Desert ecology is characterized by dry, alkaline soil, low net production and an opportunistic diet by herbivores and carnivores. The survival tactics of other organisms are physiologically based. Such tactics include completing the life cycle ahead of the anticipated dry season, and storing water with the help of specialized organs.
The desert climate is very demanding endothermic organisms. In environments where external temperatures are less than their body temperature, most endotherms can balance heat production and heat loss to maintain a comfortable temperature. However, in the desert where temperatures and soils exceed body temperature, endotherms must be able to expel large amounts of heat absorbed in this environment. To overcome the extreme conditions, endothermic deserts have adapted through means of avoidance, homeostasis relaxation, and specialization. The desert rodents at night, like kangaroo rats, will spend the day in a cool burrow deep underground, and appear at night for food. Birds are much more mobile than land-land endotherms, and therefore can avoid heat-induced dehydration by flying between water sources. To prevent overheating, many body temperatures of desert mammals have adapted to be much higher than non-desert mammals. Camels, for example, can maintain a body temperature similar to typical desert air temperatures. This adaptation allows the camel to retain large amounts of water for a long time. Other examples of higher body temperatures in desert mammals include dielectric ground squirrels, and oryx. Specific desert endothermes have evolved very specific and unique characteristics to combat dehydration. Sandgrouse men have special abdominal feathers that are capable of trapping and carrying water. This allows sandgrouse to provide a source of hydration for their chicks, which does not yet have the ability to fly to the water source itself.
Plants
Although deserts have a severe climate, some plants can still grow. Plants that can survive in dry deserts are called xerophytes, which means they are capable of long-lasting dry periods. The plants can close their stomata during the day and open them at night, when the plants can contain carbon dioxide temporarily, thanks to lower temperatures, a slight loss of water for evaporation.
Adaptations in xerophytes include resistance to heat and water loss, increased water storage capacity, and reduced leaf surface area. One of the most common families of desert plants is the cactus, which is covered with sharp thorns or feathers for defense. The feathers on certain cactus also have the ability to reflect sunlight, such as the cactus of the elderly. Certain Xerophytes, such as oleanders, have hidden stomata as a form of protection against dry, hot desert winds, allowing the leaves to retain water more effectively. Other unique adaptations can be found in xerophytes such as ocotillo, which are "leafless for most of the year, thus avoiding excessive water loss".
Exploration and Research
The harsh climate of much of the desert is a major obstacle to doing research on this ecosystem. In environments that require specific adaptations for survival, it is often difficult or even impossible for researchers to spend a long time investigating the ecology of the area. To overcome the limitations imposed by desert climates, some scientists have used technological advances in the field of remote sensing and robotics. One experiment conducted in 1997, has a special robot named Nomad who traveled through some of the Atacama Desert. During this expedition, Nomad traveled more than 200 kilometers and gave researchers a lot of photos of the sites visited along the way.
See also
- Aridisols
References
Source of the article : Wikipedia
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