Terrestrial ecosystem

Summary

Terrestrial ecosystems, which cover 28.26% of Earth's surface, are diverse and include tundra, taiga, temperate forests, tropical rainforests, grasslands, and deserts. They are characterized by water scarcity, temperature fluctuations, and greater light and gas availability compared to aquatic ecosystems. These ecosystems host a variety of organisms, such as plants from Magnoliophyta and Pinophyta, and animals like insects, birds, and mammals, all adapted to terrestrial conditions. Food webs in these systems are divided into grazing and detritus segments, with the former more prevalent in grasslands and the latter in forests. Human activities have also created extensive agroecosystems, influencing Earth's natural landscape.

Takeaways

• 🌱 There are six primary terrestrial ecosystems: tundra, taiga, temperate deciduous forest, tropical rain forest, grassland, and desert.
• 💧 Terrestrial ecosystems differ from aquatic ones due to lower water availability and greater temperature fluctuations.
• 🌤️ Light availability is higher in terrestrial ecosystems, and gases like carbon dioxide, oxygen, and nitrogen are more accessible.
• 🌳 Terrestrial environments are divided into subterranean and atmospheric portions, with photosynthesis occurring in the latter.
• 🌍 Terrestrial ecosystems cover 28.26% of Earth's surface, a smaller area compared to marine ecosystems.
• 🌿 Major plant taxa in these ecosystems belong to Magnoliophyta (about 275,000 species), Pinophyta (about 500 species), and Bryophyta (about 24,000 species).
• 🐛 Major animal taxa include Insecta (about 900,000 species), Aves (8,500 species), and Mammalia (approximately 4,100 species).
• 🌱 Organisms have adaptations for water acquisition, transport, and retention, as well as body support and temperature regulation.
• 🔗 Terrestrial organisms are integrated into functional units through energy and chemical flow relationships, depicted in trophic webs.
• 🌿 Grazing and detritus food webs are two segments of terrestrial food webs, with the former being more important in grasslands and the latter in forests.
• 🌿 Human activities have created one extensive type of terrestrial ecosystem, while eight natural types reflect Earth's climatic variations.

Q & A

What are the six primary terrestrial ecosystems?

The six primary terrestrial ecosystems are tundra, taiga, temperate deciduous forest, tropical rain forest, grassland, and desert.

How do terrestrial ecosystems differ from aquatic ecosystems in terms of water availability?

Terrestrial ecosystems have a lower availability of water compared to aquatic ecosystems, making water a critical limiting factor for life on land.

What is a key difference between the temperature fluctuations in terrestrial and aquatic ecosystems?

Terrestrial ecosystems experience greater temperature fluctuations both diurnally and seasonally than aquatic ecosystems with similar climates.

Why is the availability of light greater in terrestrial ecosystems than in aquatic ecosystems?

The atmosphere is more transparent on land than in water, allowing for greater light availability in terrestrial ecosystems.

Which gases are more available in terrestrial ecosystems and why are they important?

Carbon dioxide, oxygen, and nitrogen are more available in terrestrial ecosystems. They are essential for processes like photosynthesis, aerobic respiration, and nitrogen fixation.

How do terrestrial environments obtain water and ions?

Terrestrial environments obtain water and ions from a subterranean portion, while gases are obtained from the atmospheric portion.

What percentage of Earth's surface is covered by terrestrial ecosystems?

Terrestrial ecosystems occupy 28.26% of Earth's surface, which is approximately 55,660,000 square miles.

What are the major plant taxa found in terrestrial ecosystems?

The major plant taxa in terrestrial ecosystems are from the division Magnoliophyta with about 275,000 species and the division Pinophyta with about 500 species.

How do organisms in terrestrial ecosystems adapt to the lack of water?

Organisms have adaptations for obtaining water, transporting it within their bodies, and preventing evaporation from body surfaces.

What are the two segments that terrestrial food webs can be divided into based on plant material consumption?

Terrestrial food webs can be divided into grazing food webs, associated with the consumption of living plant material by herbivores, and detritus food webs, associated with the consumption of dead plant material by detritivores.

Which type of terrestrial ecosystem is considered the most productive and why?

Tropical forests are the most productive terrestrial ecosystems, contributing 45% of the total estimated net primary productivity on land due to their large areal extent and high average productivity.

Outlines

00:00

🌿 Overview of Terrestrial Ecosystems

Terrestrial ecosystems are land-based communities of organisms interacting with their environment. They include tundra, taiga, temperate deciduous forest, tropical rainforest, grassland, and desert. These ecosystems are characterized by limited water availability, significant temperature fluctuations, and greater light and gas availability compared to aquatic ecosystems. Terrestrial ecosystems occupy 28.26% of Earth's surface and host a diverse range of organisms, including plants from Magnoliophyta and Pinophyta, and animals from Insecta, Aves, and Mammalia. Organisms have adapted to the unique challenges of life on land, such as obtaining and conserving water, supporting their bodies in less buoyant air, and enduring temperature extremes. The functional integration of these organisms is depicted through trophic webs, with green plants at the base, and two types of food webs: grazing, based on living plant material, and detritus, based on dead plant material. The relative importance of these food webs varies by ecosystem type.

05:03

🌱 Productivity of Tropical Forests

Tropical forests are the most productive of all terrestrial ecosystems, contributing 45% of the total estimated net primary productivity on land. They are also the most extensive, covering a large portion of Earth's land surface. This high productivity is attributed to their location in regions with abundant rainfall and warm temperatures, which support a diverse array of plant and animal life. Tropical forests play a crucial role in the global carbon cycle and are vital for biodiversity conservation.

Keywords

💡Terrestrial ecosystem

A terrestrial ecosystem refers to an ecosystem found on landforms, such as continents and islands. It is characterized by the presence of various types of communities of organisms interacting with their environment. The video script discusses six primary terrestrial ecosystems, including tundra, taiga, temperate deciduous forest, tropical rain forest, grassland, and desert. These ecosystems are distinguished from aquatic ones by factors such as water availability and temperature fluctuations, which are central to the video's exploration of how life adapts to different terrestrial conditions.

💡Water as a limiting factor

In the context of terrestrial ecosystems, water serves as a limiting factor due to its lower availability compared to aquatic ecosystems. This concept is crucial as it influences the types of organisms that can thrive in these environments and the adaptations they develop to conserve water. The script highlights how terrestrial ecosystems must contend with the challenges of water scarcity, which shapes the structure and function of these ecosystems.

💡Temperature fluctuations

Terrestrial ecosystems experience greater temperature fluctuations both diurnally and seasonally compared to aquatic ecosystems. This keyword is significant as it underscores the harsh conditions that terrestrial organisms must adapt to. The video likely discusses how these fluctuations affect the survival strategies of plants and animals, such as through dormancy or migration.

💡Light availability

The availability of light is greater in terrestrial ecosystems than in aquatic ones because the atmosphere allows more light to penetrate than water does. This is important for the video's theme as it directly relates to photosynthesis, the process by which green plants convert light energy into chemical energy. The script probably explains how the abundance of light is a driving factor in the productivity of terrestrial ecosystems.

💡Gas availability

Gases such as carbon dioxide, oxygen, and nitrogen are more available in terrestrial ecosystems, which is essential for processes like photosynthesis and respiration. The video likely discusses how the accessibility of these gases influences the metabolic activities of organisms and the overall health of the ecosystem.

💡Adaptive radiation

Adaptive radiation refers to the rapid diversification of a group of organisms into new forms and ecological niches. The script mentions that terrestrial ecosystems have been a major site of adaptive radiation for both plants and animals, indicating the diversity and evolutionary adaptability of life on land. This concept is key to understanding the variety of species and their roles within these ecosystems.

💡Trophic webs

Trophic webs are schematic diagrams that illustrate the feeding relationships among organisms within an ecosystem. The video script discusses how these webs are structured with green plants at the base, as primary producers, and how they branch out to include various consumers. This concept is central to understanding the flow of energy and nutrients through terrestrial ecosystems.

💡Grazing food webs

Grazing food webs are those in which the primary energy flow comes from the consumption of living plant material by herbivores. The script notes that these food webs are more important in grasslands, where a significant portion of primary productivity is consumed by herbivores. This keyword is significant as it highlights one of the primary ways energy is transferred in certain terrestrial ecosystems.

💡Detritus food webs

Detritus food webs involve the consumption of dead organic material by detritivores. The video script contrasts these with grazing food webs, indicating that detritus food webs are more important in forests, where a smaller proportion of primary productivity is consumed by herbivores. This concept is crucial for understanding the decomposition processes and nutrient recycling in terrestrial ecosystems.

💡Productivity

Productivity in the context of ecosystems refers to the rate at which energy is fixed by producers and made available to other organisms. The script mentions that tropical forests are the most productive of all terrestrial ecosystems, contributing a significant portion of the Earth's net primary productivity. This keyword is essential for understanding the capacity of different ecosystems to support life and the ecological services they provide.

💡Agroecosystems

Agroecosystems are ecosystems that are managed and manipulated by humans for agricultural purposes. The script includes cultivated lands, grasslands, and savannas used for grazing as examples of agroecosystems. This keyword is important as it relates to the human impact on terrestrial ecosystems and the integration of natural and managed landscapes.

Highlights

Terrestrial ecosystems are found on landforms and include six primary types: tundra, taiga, temperate deciduous forest, tropical rain forest, grassland, and desert.

Terrestrial ecosystems are characterized by lower water availability, greater temperature fluctuations, and higher light availability compared to aquatic ecosystems.

Gases such as carbon dioxide, oxygen, and nitrogen are more available in terrestrial ecosystems, which is crucial for processes like photosynthesis and respiration.

Terrestrial environments are segmented into subterranean and atmospheric portions, affecting how organisms obtain water, ions, and gases.

Terrestrial ecosystems cover 28.26% of Earth's surface, despite being a recent development in the history of life.

Terrestrial ecosystems have been a significant site of adaptive radiation for both plants and animals.

Major plant taxa in terrestrial ecosystems belong to the divisions Magnoliophyta and Pinophyta, with significant species counts.

Major animal taxa include Insecta, Aves, and Mammalia, with a vast number of species contributing to the ecosystem's biodiversity.

Organisms in terrestrial ecosystems have evolved adaptations for water acquisition, transport, and evaporation prevention.

Terrestrial organisms have developed traits for body support in less buoyant atmospheric conditions.

Adaptations to withstand temperature extremes, wind, and humidity are common among terrestrial organisms.

Terrestrial organisms have evolved methods for gamete transport in environments with less effective fluid flow.

Functional integration in terrestrial ecosystems is facilitated by dynamic relationships and energy and chemical flow processes.

Trophic webs in terrestrial ecosystems are based on feeding relationships, with green plants at the base as primary producers.

Grazing and detritus food webs are two segments of terrestrial food webs, with varying importance across different ecosystems.

Human activities have led to the creation of extensive terrestrial ecosystems, in addition to the eight natural types.

Natural terrestrial ecosystems reflect variations in precipitation and temperature across Earth's surface.

Tropical forests are the most productive terrestrial ecosystems, contributing significantly to global net primary productivity.

Transcripts

A terrestrial ecosystem is an ecosystem found only on landforms. Six primary

terrestrial ecosystems exist: tundra, taiga, temperate deciduous forest,

tropical rain forest, grassland and desert.

A community of organisms and their environment that occurs on the land

masses of continents and islands. Terrestrial ecosystems are distinguished

from aquatic ecosystems by the lower availability of water and the consequent

importance of water as a limiting factor. Terrestrial ecosystems are

characterized by greater temperature fluctuations on both a diurnal and

seasonal basis than occur in aquatic ecosystems in similar climates. The

availability of light is greater in terrestrial ecosystems tan in aquatic

ecosystems because the atmosphere is more transparent in land than in water.

Gases are more available in terrestrial ecosystems than in aquatic ecosystems.

Those gases include carbon dioxide that serves as a substrate for

photosynthesis, oxygen that serves as a substrate in aerobic respiration, and

nitrogen that serves as a substrate for nitrogen fixation. Terrestrial

environments are segmented into a subterranean portion from which most

water and ions are obtained, and an atmospheric portion from which gases are

obtained and where the physical energy of light is transformed into the organic

energy of carbon-carbon bonds through the process of photosynthesis.

Terrestrial ecosystems occupy 55,660,000 mi², or 28.26% of Earth's surface.

Although they are comparatively recent in the history of life and occupy a much

smaller portion of Earth's surface than marine GUCCI FLIP FLOPSecosystems,

terrestrial ecosystems have been a major site of adaptive radiation of both

plants and animals. Major plant taxa in terrestrial ecosystems are members of

the division Magnoliophyta, of which there are about 275,000 species, and the

division Pinophyta, of which there are about 500 species. Members of the

division Bryophyta, of which there are about 24,000 species, are also important

in some terrestrial ecosystems. Major animal taxa in terrestrial ecosystems

include the classes Insecta with about 900,000 species, Aves with 8,500

species, and Mammalia with approximately 4,100 species.

Organisms in terrestrial ecosystems have adaptations that allow them to obtain

water when the entire body is no longer bathed in that fluid, means of

transporting the water from limited sites of acquisition to the rest of the

body, and means of preventing the evaporation of water from body surfaces.

They also have traits that provide body support in the atmosphere, a much less

buoyant medium than water, and other traits that render them capable of

withstanding the extremes of temperature, wind, and humidity that

characterize terrestrial ecosystems. Finally, the organisms in terrestrial

ecosystems have evolved many methods of transporting gametes in environments

where fluid flow is much less effective as a transport medium.

The organisms in terrestrial ecosystems are integrated into a functional unit by

specific, dynamic relationships due to the coupled processes of energy and

chemical flow. Those relationships can be summarized by schematic diagrams of

trophic webs, which place organisms according to their feeding

relationships. The base of the food web is occupied by green plants, which are

the only organisms capable of utilizing the energy of the Sun and inorganic

nutrients obtained from the soil to produce organic molecules. Terrestrial

food webs can be broken into two segments based on the status of the

plant material that enters them. Grazing food webs are associated with the

consumption of living plant material by herbivores. Detritus food webs are

associated with the consumption of dead plant material by detritivores. The

relative importance of those two types of food webs varies considerably in

different types of terrestrial ecosystems. Grazing food webs are more

important in grasslands, where over half of net primary productivity may be

consumed by herbivores. Detritus food webs are more important in forests,

where less than 5% of net primary productivity may be consumed by

herbivores. There is one type of extensive

terrestrial ecosystem due solely to human activities and eight types that

are natural ecosystems. Those natural ecosystems reflect the variation of

precipitation and temperature over Earth's surface. The smallest land areas

are occupied by tundra and temperate grassland ecosystems, and the largest

land area is occupied by tropical forest. The most productive ecosystems

are temperate and tropical forests, and the least productive are deserts and

tundras. Cultivated lands, which together with grasslands and savannas

utilized for grazing are referred to as agroecosystems, are of intermediate

extent and productivity. Because of both their areal extent and their high

average productivity, tropical forests are the most productive of all

terrestrial ecosystems, contributing 45% of total estimated net primary

productivity on land. See also

Aquatic-terrestrial subsidies References