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.