Read the passage on the composition of soil. As you read, fill in the verbs in the simple present tense. Choose the verbs from the box. mix contain include form come consist grow contribute minerals Soil is made up of two main components. The first component is bits of mineral particles, which cona from larger rocks. These salts of iron, calcium, potassium, magnesium and phosphorus, etc. Many of these minerals are needed by plants for their growth. The second component is humus, which is dark brown in colour and _ of the decaying remains of plants and animals. A variety of dead and decaying organisms to the formation of humus. A lot of it by decaying leaves of plants. Small plants, such as mosses, lichens and ferns. in small pieces of rocks. When they die, they with the soil and form humus. Soil also water, air and living organisms.
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Answer:
Soil is one of the most important elements of an ecosystem, and it contains both biotic and abiotic factors. The composition of abiotic factors is particularly important as it can impact the biotic factors, such as what kinds of plants can grow in an ecosystems.
Soil Layers
Soil is composed of both biotic—living and once-living things, like plants and insects—and abiotic materials—nonliving factors, like minerals, water, and air.
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Soil Composition
Soil is one of the most important elements of an ecosystem, and it contains both biotic and abiotic factors. The composition of abiotic factors is particularly important as it can impact the biotic factors, such as what kinds of plants can grow in an ecosystem.
Soil Layers
Soil is composed of both biotic—living and once-living things, like plants and insects—and abiotic materials—nonliving factors, like minerals, water, and air.
Soil contains air, water, and minerals as well as plant and animal matter, both living and dead. These soil components fall into two categories. In the first category are biotic factors—all the living and once-living things in soil, such as plants and insects. The second category consists of abiotic factors, which include all nonliving things—for example, minerals, water, and air. The most common minerals found in soil that support plant growth are phosphorus, and potassium and also, nitrogen gas. Other, less common minerals include calcium, magnesium, and sulfur. The biotic and abiotic factors in the soil are what make up the soil’s composition.
Soil composition is a mix of soil ingredients that varies from place to place. The Natural Resources Conservation Service (NRCS)—part of the U.S. Department of Agriculture—has compiled soil maps and data for 95 percent of the United States. The NRCS has found that each state has a “state soil” with a unique soil “recipe” that is specific to that state. These differing soils are the reason why there is such a wide variety of crops grown in the United States.