Pond Life: Exploring Microbial Ecosystems

Introduction to Microbial Worlds

• Thousands of microbial organisms exist within a single drop of water.
• Pond Life explores the microbial wilderness around us.

Cyanobacteria: The First Photosynthesizers

• Evolved over 2 billion years ago.
• First organisms to perform photosynthesis, creating sugars from sunlight.
• Photosynthesis byproduct: oxygen, which transformed Earth's atmosphere to oxygen-rich.
• Cyanobacteria remain abundant today, found easily in ponds.

Cyanobacteria Habitat and Diversity

• About 3,000 described species.
• Found in diverse habitats: freshwater ponds, Arctic oceans, soil.
• Cyanobacteria make ponds green, visible as tiny, floating green particles.
• Colonies consist of multiple cyanobacterial cells.

Species Identification and Characteristics

• Microcystis Genus:
  • Colonies in clear mucus, start from one cell.
  • Fast growth in warm waters leads to blooms.
• Dolichospermum Genus:
  • Helical colonies with specialized heterocysts.
  • Heterocysts absorb nitrogen, dividing tasks efficiently within colonies.

Observation and Collection in Central Park

• Observations in Central Park show cyanobacteria's role in the ecosystem.
• Use of microscopes to examine unseen worlds.
• Aphanizomenon Genus:
  • Forms long, filamentous colonies, active under time-lapse.

Predation on Cyanobacteria

• Ciliate Genus Nassila:
  • Specialist predator of cyanobacteria, engulfs them like spaghetti.

Lab Study and Importance of Sterility

• Sample collection for lab analysis.
• Importance of keeping cultures sterile to avoid contamination.
• Use of growth media: vitamins, minerals, salts.
• Biocidal membrane safety cabinet for sterile environment.
• Growth chamber maintains temperature and light for cultures.

Challenges and Goals of Studying Cyanobacteria

• Cyanobacterial blooms can be toxic to animals.
• Study of flagellates, Euclidna algae, Cholodictaean among blooms.
• Goal: Isolate and identify species, understand bloom communities.
• Research aims to comprehend causes of blooms, important for ecological insights.

Conclusion

• Even urban areas have complex microbial ecosystems.
• Lab studies help understand microbial life in these environments.