Microalgae | UPSC

A recently published study on microalgae sheds light on their remarkable strategies for coping with global warming and their pivotal role in the face of climate change impacts. Microalgae, also known as microphytes, are microscopic algae found in freshwater and marine systems. This study has unveiled their distinctive adaptations and significance in the ever-changing environmental landscape.

Contents

Exploring Key Findings

Unique Strategy for Global Warming Coping

Microalgae have developed a unique strategy to adapt to global warming, particularly in the context of climate change impacts on oceans.

Reduced Nutrient Availability in the Sea

One of the consequences of climate change is the reduction of nutrient availability in the ocean. This is due to the warming of oceans, which disrupts the natural mixing of surface and deep-sea waters.

Result: Nutrient scarcity at the surface of the ocean, impacting primary producers like microalgae.
Equivalent Scenario: This scarcity can be likened to reduced crop yields on land due to the scarcity of iron- and nitrogen-rich fertilizers.

Iron Significance

Iron plays a crucial role in the growth of microalgae, as it enables them to harness sunlight for energy.

Challenge: Approximately 35% of the ocean surface, particularly in the Southern Ocean, lacks sufficient iron for the growth of microalgae.
Relevance: The Southern Ocean is not only the largest iron-limited aquatic ecosystem but also hosts the largest populations of krill, fish, penguins, and whales—all of which depend on primary producers like microalgae for their survival.

Protein Emergence: Rhodopsin

Microalgae have also adapted through the emergence of a protein called rhodopsin, which has a role similar to a human eye protein used for dim light vision.

Role: Rhodopsin is light-responsive and supports microalgae growth by using sunlight, as opposed to traditional chlorophyll.
Microbial Rhodopsins: These proteins are assumed to be major light capturers in the ocean and have a comparable capacity for energy and food generation through photosynthesis, similar to chlorophyll-based photosynthesis.
Distribution: They are more concentrated in low latitudes due to reduced ocean water mixing and lower nutrient levels.

Understanding Microalgae

Also Known As: Microphytes

Definition: Microalgae are microscopic algae found in both freshwater and marine systems.
Characteristics: They are typically unicellular and can exist individually, in chains, or in groups. Microalgae lack roots, stems, and leaves but possess the capability for photosynthesis.

Significance in the Ecosystem

Role in Ocean Ecosystem

Microalgae serve as the foundation of the marine food chain, providing sustenance for numerous marine species.

Environmental Impact

Microalgae play a crucial role in mitigating climate change by capturing carbon dioxide from the atmosphere through photosynthesis, contributing to the regulation of greenhouse gases.