Difference Between Gaseous and Sedimentary Biogeochemical Cycles

The key difference between gaseous and sedimentary biogeochemical cycles is their main reservoir of the element. In gaseous biogeochemical cycles, the main reservoir of the element is the air or ocean. But, the main reservoir of the element is the Earth crust in sedimentary biogeochemical cycles.

Biogeochemical cycles are pathways by which substances mainly circulate through biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydrosphere) parts of Earth. These cycles explain the movement of a particular element via living and nonliving matter in an ecosystem. There are several natural cycles including nitrogen cycle, carbon cycle, water cycle, phosphorus cycle, and sulfur cycle. These cycles are extremely important for the existence of life and transforming energy and mater into usable forms to support ecosystem functioning.

Each cycle shows a balance in cycling between different compartments. However, human activities have greatly affected these natural cycles, creating altered and accelerated cycles that can influence the climate and pose a threat to biodiversity, food security, human health, and water quality, etc. Generally, biogeochemical cycles can be categorized into two main types as gaseous and sedimentary.

CONTENTS

1. Overview and Key Difference
2. What are Gaseous Biogeochemical Cycles
3. What are Sedimentary Biogeochemical Cycles
4. Similarities Between Gaseous and Sedimentary Biogeochemical Cycles
5. Side by Side Comparison – Gaseous vs Sedimentary Biogeochemical Cycles in Tabular Form
6. Summary

What are Gaseous Biogeochemical Cycles?

Gaseous biogeochemical cycles circulate through the atmosphere and hydrosphere. Therefore, the main reservoirs of gaseous biogeochemical cycles are air and ocean. Nitrogen, oxygen, carbon, and water cycles are some of the gaseous biogeochemical cycles. Especially in the nitrogen cycle, the major reservoir is the atmosphere. In the atmosphere, more than 78% is occupied by nitrogen gas (N₂). Moreover, the main reservoir of CO₂ and O₂ is also the atmosphere.

Atmospheric gases are absorbed by plants and aerobic organisms. Plants fix carbon dioxide and produce carbohydrates. We breathe air containing oxygen. In addition, gaseous cycles take place quickly than sedimentary cycles.

What are Sedimentary Biogeochemical Cycles?

Sedimentary biogeochemical cycles are the cycles in which the main reservoir is the soil and sedimentary rocks. Therefore, the elements of sedimentary biogeochemical cycles mainly circulate through the land to water to sediments.  Basically, these cycles have a solution phase and rock phase.

From the Earth’s crust, minerals are released by the weathering process. Then they become salts in water. These elements circulate through a series of organisms and finally come to the sea. Some salts deposit in rock while some salts settle in sediments. Most importantly, these elements do not move through the air. Iron, calcium, phosphorus, and other more earthbound elements are sedimentary biogeochemical cycles.

What are the Similarities Between Gaseous and Sedimentary Biogeochemical Cycles?

• Gaseous and sedimentary cycles are two main categories of biogeochemical cycles.
• They depict the movements of elements through different compartments of the Earth.
• They are natural cycles.
• However, human activities accelerate and alter both types of cycles.

What is the Difference Between Gaseous and Sedimentary Biogeochemical Cycles?

Gaseous cycles are cycles in which the main reservoir of the element is air or water. Meanwhile, sedimentary cycles are cycles in which the main reservoir of the element is Earth crust. So, this is the key difference between gaseous and sedimentary biogeochemical cycles. For example, nitrogen, oxygen, carbon, and water cycles are gaseous cycles, while iron, calcium, phosphorus, and other more earthbound elemental cycles are sedimentary cycles.

Moreover, gaseous biogeochemical cycles are fast, while the sedimentary biogeochemical cycles are slow. Therefore, this is another difference between gaseous and sedimentary biogeochemical cycles.

The below infographic shows more comparisons on the difference between gaseous and sedimentary biogeochemical cycles.

Summary – Gaseous vs Sedimentary Biogeochemical Cycles

Gaseous biogeochemical cycles mainly move through the atmosphere. Therefore, their main reservoir is air or ocean. In contrast, sedimentary biogeochemical cycles move through soil or the Earth’s crust, so their main reservoir is the lithosphere. So, this is the key difference between gaseous and sedimentary biogeochemical cycles. Furthermore, gaseous cycles occur very fast, while sedimentary cycles are very slow. For example, nitrogen, oxygen, carbon, and water cycles are gaseous cycles, while iron, calcium, phosphorus, and other more earthbound elemental cycles are sedimentary cycles.

Reference:

1.“Biogeochemical Cycle.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 16 June 2016, Available here.
2. Doršner, Kamala, et al. “3.2 Biogeochemical Cycles.” Environmental Biology, Available here.

Image Courtesy:

1. “Nitrogen Cycle” By Cicle_del_nitrogen_de.svg: *Cicle_del_nitrogen_ca.svg: Johann Dréo (User:Nojhan), traduction de Joanjoc d’après Image:Cycle azote fr.svg.derivative work: Burkhard (talk)Nitrogen_Cycle.jpg: Environmental Protection Agencyderivative work: Raeky (talk) – Cicle_del_nitrogen_de.svgNitrogen_Cycle.jpg (CC BY-SA 3.0) via Commons Wikimedia
2. “Phosphorus cycle” By BonniemfIncorporates work by NASA Earth Science Enterprise – Reworked by Bonniemf from the public domain file File:Carbon cycle-cute diagram.svg (CC BY-SA 3.0) via Commons Wikimedia