Endangered forest gardenia : Listed as federally endangered, the forest gardenia is a small tree with distinctive flowers. It is found only in five of the Hawaiian Islands in small populations consisting of a few individual specimens.
The availability of energy and nutrient sources affects species distribution and their adaptation to land or aquatic habitats. Energy from the sun is captured by green plants, algae, cyanobacteria, and photosynthetic protists. These organisms convert solar energy into the chemical energy needed by all living things.
Light availability can be an important abiotic force directly affecting the evolution of adaptations in photosynthesizers. For instance, plants in the understory of a temperate forest are shaded when the trees above them in the canopy completely leaf out in the late spring.
Not surprisingly, understory plants have adaptations to successfully capture available light. One such adaptation is the rapid growth of spring ephemeral plants, such as the spring beauty. These spring flowers achieve much of their growth and finish their life cycle reproduce early in the season before the trees in the canopy develop leaves.
Ephemeral plant : The spring beauty is an ephemeral spring plant that flowers early in the spring to avoid competing with larger forest trees for sunlight. In aquatic ecosystems, the availability of light may be limited because sunlight is absorbed by water, plants, suspended particles, and resident microorganisms.
Toward the bottom of a lake, pond, or ocean, there is a zone that light cannot reach. Photosynthesis cannot take place there and, as a result, a number of adaptations have evolved that enable living things to survive without light.
For instance, aquatic plants have photosynthetic tissue near the surface of the water. The broad, floating leaves of a water lily cannot survive without light. In environments such as hydrothermal vents, some bacteria extract energy from inorganic chemicals because there is no light for photosynthesis. The availability of nutrients in aquatic systems is also an important aspect of energy or photosynthesis.
Many organisms sink to the bottom of the ocean when they die in the open water. When this occurs, the energy found in that organism is sequestered for some time unless ocean upwelling occurs. Ocean upwelling is the rising of deep ocean waters that occurs when prevailing winds blow along surface waters near a coastline.
As the wind pushes ocean waters offshore, water from the bottom of the ocean moves up to replace this water. As a result, the nutrients once contained in dead organisms become available for reuse by other living organisms. Upwelling : Ocean upwelling is an important process that recycles nutrients and energy in the ocean. As wind green arrows pushes offshore, it causes water from the ocean bottom red arrows to move to the surface, bringing up nutrients from the ocean depths.
In freshwater systems, the recycling of nutrients occurs in response to air temperature changes. The nutrients at the bottom of lakes are recycled twice each year: in the spring and fall turnover, which recycles nutrients and oxygen from the bottom of a freshwater ecosystem to the top of a body of water. These turnovers are caused by the formation of a thermocline: a layer of water with a temperature that is significantly different from that of the surrounding layers.
In wintertime, the surface of lakes found in many northern regions is frozen. The deepest water is oxygen poor because the decomposition of organic material at the bottom of the lake uses up available oxygen that cannot be replaced by means of oxygen diffusion into the water due to the surface ice layer. In springtime, air temperatures increase and surface ice melts. The water at the bottom of the lake, displaced by the heavier surface water, rises to the top.
As it rises, the sediments and nutrients from the lake bottom are brought along with it. During the summer months, the lake water stratifies, or forms layers, with the warmest water at the lake surface. The oxygen-rich water at the surface of the lake then moves to the bottom of the lake, while the nutrients at the bottom of the lake rise to the surface. During the winter, the oxygen at the bottom of the lake is used by decomposers and other organisms requiring oxygen, such as fish.
Nurient recycling in freshwater systems : The spring and fall turnovers are important processes in freshwater lakes that act to move the nutrients and oxygen at the bottom of deep lakes to the top. Surface water temperature changes as the seasons progress, causing denser water to sink. Temperature affects the physiology of living things as well as the density and state of water.
This is a reflection of evolutionary response to typical temperatures. Enzymes are most efficient within a narrow and specific range of temperatures; enzyme degradation can occur at higher temperatures. Therefore, organisms must either maintain an internal temperature or inhabit an environment that will keep the body within a temperature range that supports metabolism. Some animals have adapted to enable their bodies to survive significant temperature fluctuations, as seen in hibernation or reptilian torpor.
Similarly, some bacteria have adapted to survive in extremely-hot temperatures found in places such as geysers. Such bacteria are examples of extremophiles: organisms that thrive in extreme environments. Temperature can limit the distribution of living things. An example of this is a cactus houseplant. Cacti originally come from deserts where they grow in bright sunlight. Other plants have evolved to grow in shade.
Many orchids, which are also kept as houseplants, grow on trees in the rainforest and have evolved for optimum growth in darker conditions. If you were to put an orchid on a bright windowsill and a cactus in a dark corner of your room neither plant would grow well.
Both animals and plants have evolved to grow healthily at their optimum temperatures. If you planted either your cactus or orchid houseplants outside in cold temperatures, they would die. Similarly, animals that have evolved to live at the North Pole, such as the polar bear, could not survive in warmer conditions. More people kill houseplants by overwatering than by under-watering them.
Many plants cannot survive in waterlogged soils. Their roots are unable to respire , they rot and the plant dies. Other plants, such as pitcher plants, grow best in bogs where the moisture levels are high. When you reach out to them, you will need the page title, URL, and the date you accessed the resource.
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You cannot download interactives. An abiotic factor is a non-living part of an ecosystem that shapes its environment. In a terrestrial ecosystem, examples might include temperature, light, and water. In a marine ecosystem, abiotic factors would include salinity and ocean currents. Abiotic and biotic factors work together to create a unique ecosystem. Learn more about abiotic factors with this curated resource collection. Students define and provide examples of abiotic and biotic factors of different ecosystems.
Then they investigate the importance of abiotic factors and physical processes within ocean ecosystems. The oriental whip snake Ahaetulla prasina is a common snake found throughout parts of Asia. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.
Skip to content. Far more species of organisms exist in regions of high humidity compared to arid regions. Some organisms, such as fish, can only exist in a marine environment, and rapidly die when removed from water. Other organisms can survive in some of the driest environments in the world. Plants such as cacti have developed the Crassulacean Acid Metabolism system of photosynthesis, in which they open their stomata at night, when it is much cooler, to take in carbon dioxide, store it as malic acid, and then process it during the day.
Soil conditions can also have an effect on organisms. For instance, the pH of the soil can have an effect on the types of plants which can grow in it. Plants such as ericas, ferns and protea species grow better in acidic soils.
In contrast, lucerne and many species of xerophytes are adapted to alkaline conditions.
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