Aquatic & Terrestrial Plants

Terrestrial plants are defined as any plant that grows on, in or from the land. By contrast, aquatic plants are plants that thrive when their roots are submerged in water. If you're a gardener considering plants that may thrive in your home environment, knowing the differences between aquatic and terrestrial plants may be very helpful.

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Generally speaking, terrestrial plants can be defined as any set of plants that grow on the land or need to be on dry land to survive. The term terrestrial is used to differentiate plants like these from plants that need to be in the water, grow only out of trees or grow out of rock.

Terrestrial plants fall under the large category of land plants. Land plants are the kind of plants that get the nutrients they need to survive both from the air and the soil. These plants can't survive if immersed or submerged in water as they'll become waterlogged and die. The roots of terrestrial plants are planted deeply in the soil. These roots help to stabilize the plants and draw minerals and any needed moisture from the soil.

Aquatic plants are plants that live in water. This means that they require being submersed to survive or that they can only grow and thrive in water. Many aquatic plants can tolerate being emersed, meaning they're out of the water for short periods of time, but require immersion in water for long-term survival.

There are some plants that simply can't tolerate being emersed at all, but this is rare. These plants can only live when fully immersed in water. Most macroalgae require total submersion in water for the span of its entire life. Most aquatic plants, however, have roots underwater but can only grow or flower in a partially emersed state.

There's a difference between aquatic and terrestrial plants, but the lines between them are often blurred. This is because there are many plants that are technically considered to be terrestrial plants because they grow in or on land but are able to tolerate submersion in water and can even thrive in environments where they're exposed regularly to water. Many plants have different variations of their own species, and some of these can handle submersion in water, while other species from the same plant family perish in those conditions.

In environments where heavy rain or flooding is common, plants that can survive both dry or wet conditions straddle the line between aquatic and terrestrial. There are terrestrial plants that can survive periods of heavy rain or waterlogging and still survive; however, these wouldn't be considered aquatic plants. Many species of terrestrial plants can tolerate submersion or inundation of water for a short period, but prolonged exposure often results in death.

There are many similarities between aquatic and terrestrial plants. Both varieties of the plant are green, with leaves, roots and the ability to flower. Land plants are typically taller than wide and have a branched root system. Water plants are typically wider and have spongier leaves, which allow the plant to float on water. Aquatic plants don't root down into the soil. Their roots hang in the water and they're able to move around.

There are thousands of species of terrestrial plants. They range from trees and flowers to grasses, weeds and vines. Some terrestrial plants are considered to be "land invasive." This means that they were either accidentally or purposefully introduced into the environment and have a negative effect on the preexisting species and conditions. The consequences of land invasive terrestrial plant life can be significant, affecting agriculture and recreation but also public health and the economy.

The burning bush shrub is an example of a deciduous, terrestrial plant. It has reddish-yellow leaves and a fruit that's similar to holly berries. It's visible in the eastern United States. The common reed is another example of a terrestrial plant. It's a tall grass that blooms perennially and has wide pointy leaves that can be rough and sharp in texture. It flowers with a fluffy, solid bloom that generally becomes visible between July and October.

Russian olive trees are another bush that's both terrestrial and considered to be invasive. The leaves are ovular and scaly. The flowers are highly fragrant and produce a seed-like fruit. Another terrestrial plant is the white poplar tree. The white poplar is identified by its bark, which begins its life as a whitish-green color and later wrinkles and turns gray as the tree ages.

Aquatic plants may live in either saltwater or freshwater areas. While few species can tolerate the conditions of perpetual saltwater submersion, there are some that thrive in that environment. Other names for aquatic plants include hydrophyte and macrophyte. The white lotus is one example of an aquatic plant. It's a flowering plant with white petals and many stamens. It sits on the surface of freshwater ponds, and it's roots and stalks are often used in traditional medicine.

The yellow skunk cabbage is an aquatic plant that doesn't require being submerged in water but generally is found in damp, swampy environments. It's typically seen alongside streams and brooks and has a distinctive skunky odor that's often detectable in its vicinity. It's generally one of the first plants to begin to flower in spring.

The Nelumbo is a variety of aquatic plant that has leaves that sit on top of the water and long stalks that extend above it. The Nelumbo flowers with large bright-pink blossoms and is another variety of the lotus plant.

The water hyacinth is a free-floating plant, and it's aquatic. They can rise to almost a meter in height above the surface of the water. They have long stalks that are a dark greenish purple and the blooms have lavender petals.

Photosynthesis can be broadly defined as the method by which plant life derives nutrients from the sun and the atmosphere and turns it into chemical energy in order to survive. The type of photosynthesis most common to plants is called oxygenic photosynthesis. The process of oxygenic photosynthesis requires light energy to transfer electrons from water molecules into carbon dioxide. This produces carbohydrates and oxygen, which the plant uses as nourishment and energy.

In addition to helping the plant survive, photosynthesis is critical for human survival. It's a counterweight to respiration. All respiring organisms produce carbon dioxide when they breathe. Plants take in this carbon dioxide and, through the process of oxygenic photosynthesis, reintroduce oxygen into the atmosphere. This is critical for the survival of all animals.

A critical piece of the photosynthetic process is the pigments in plants. The pigments are the color molecules in plants, and different pigments absorb different wavelengths of light. These different wavelengths provide the necessary nourishment and energy for each respective plant. Photosynthesis is one of the best examples of plant adaptation to the natural environment in order to ensure its survival.