Viruses are the most abundant and diverse life form on Earth. In Chapter 1 of this
dissertation, a global census of the number of viral particles showed that 6.03 x 1031 viral
particles are distributed across almost every ecosystem. The global census results showed
that most viruses are in soils and sediments, two unexplored biomes for viral diversity.
Accurate and fast bioinformatics methods to explore viral and bacterial composition in
metagenomes are presented in Chapter 2 as “Fragment Recruitment Assembly Purification.”

Viruses are the most abundant and diverse life form on Earth. In Chapter 1 of this
dissertation, a global census of the number of viral particles showed that 6.03 x 1031 viral
particles are distributed across almost every ecosystem. The global census results showed
that most viruses are in soils and sediments, two unexplored biomes for viral diversity.
Accurate and fast bioinformatics methods to explore viral and bacterial composition in
metagenomic datasets are presented in Chapter 2 as “Fragment Recruitment Assembly …