Microorganism in terrestrial ecosystem
Mycorrhizae
Type
Agrobacterium tumefaciens
Arbuscular Mycorrhizae
Micorrhizal Associations
Ectomycorrhizae
Fungi that remain extracellular, forming a sheath of interconnecting filaments around the root.
Endomycorrhizae
Fungi that enter the root hair
Mutualistic fungi associatons
Phyllosphere microorganism
SSU rRNA analysisi shows millions of new bacteria yet discovered
Aerial surfaces of plant
Phyllosphere
Production of SOM
Phosphorus
Is the limiting element in most freshwater system
Also present in fertilizers
Nitrogen
Nitrogen saturation
Level in soil impacted by nitrogen release
C/N of 20 or less results in loss of soluble nitrogen from the system.
Nitrogen in the soil Ecosystem
Fertilizer often added to agricultural soils to increase nitrogen level
Small fraction become SOM
Release of carbon dioxide and biomass production
Soil as microbial habitat
Soil organic matter
Hold water for plant use
Maintain soil structure
Retain nutrient
Level of microbial diversity in soil habitat on earth
Is very complex and contain a large variety of habitat
Other plant pathogen
Viruses
Deep Subsurface
Deep Hot Biosphere
The subsurface Biosphere
Rhizosphere and Rhizoplane Microorganism
Roles of microbes in Rhizopshere and Rhizoplane
Promotion of plant growth
Synthesis and degradation of organic matter
Labile source of nutrient, creating microbial loop
Rhizoplane
surface
Rhizosphere
Volume os soil around the root influenced by materials releases from root
Microorganism
Microbe plant interaction
Endophytes
Microbes that colonize internal plant tissues
Epiphytes
Microbes that live on the surface of plants
4 functional group of soil
Litotrophs or Chemoautotroph
3 genera function of soil fungi
Pathogens
Mutualistic
Decomposer
Microbial loop
Differs fron that opearting in photic zone of the open ocean
Soil Metagenomics
Community genome size
Category of soil
Organic soil possesses at least 20% of organic carbon
Mineral soil = less than 20 % organic carbon ( most of Earth's soils.)
Physicochemical condition which affect the microbial populations
E)Soil
Well drained soil well
D)Acidity & Alkalinity
Influenced by microbial activity
Usually pH 4 - 8.5
C)Temperature
Determine the composition of soil microflora (sandy beach)
B)Water
Affects movement of microorganism between pores and particles.
Dependant on rainfall, particle size, drainage.
Thin water film = Oxygen higher
A)Surface
Clay particle
enough nutrient & moisture
Smooth
