Chapter 15: Terrestrial Ecosystems Flashcards
What characteristics are biomes based on?
Vegetation
What term describes categories of ecosystems based on vegetation characteristics?
Biomes
What are the primary producers in terrestrial ecosystems?
Plants
What is critical for primary production to be available in terrestrial ecosystems?
Soils, soil quality
What forms through microbial decomposition of plant and animal matter?
Soil
What two things does soil combine with?
Abiotic minerals, Excreted nutrients
What are the layers that soil forms called?
Horizons
What is a soil horizon based on?
Physical characteristics
What is the deepest layer of soil?
Bedrock
What soil horizon is mostly inorganic matter?
C Horizon
What is the B Horizon also known as?
Subsoil
What horizon is extremely rich in organic soils?
A Horizon
What is the A Horizon also known as?
Topsoil
What soil horizon is exposed organic matter on the soil surface?
O Horizon
What horizon layer is actively undergoing the process of decomposition?
O Horizon
What is soil composed of on a macroscopic level?
Solid, pore
What can be seen within a soil pore?
Root, Fungal hyphae, Particle aggregate
What can be seen surrounding the fungal hyphae in soil?
Humic material, Clay Particles, Bacteria
What results in the incomplete breakdown on lignin?
Humic material
Where do microbes aggregate near in soil?
Pores
Why do microbes aggregate near pores in soil?
Access nutrients/water
What is lignin/lignocellulose degraded by?
Extracellular enzymes
What type of microbe are extracellular enzymes mostly secreted by?
Fungi
What is the area of soil immediately surrounding plant roots possessing large amounts of organic carbon?
Rhizosphere
What is the cause of rhizospheres having higher numbers of microbes than bulk soil?
Excess carbon
What can result between plants and microbes in the rhizosphere?
Symbiosis
What symbiotic benefit do plants give to microbes?
Organic carbon
What type of microbe benefits from a rhizosphere?
Heterotrophic
What 4 benefits do microbes provide for plants in the rhizosphere?
Hormone production, Antibiotic production, Nitrogen fixation, Phosphate solubilization
What term describes the use of microbes to consume and remove human made materials from soil?
Bioremediation
What term describes chemicals not normally found in nature?
Xenobiotics
What term describes xenobiotic’s characteristic of being difficult to degrade quickly?
Recalcitrant
What term describes the addition of oxygen and limiting nutrients which promotes microbial activity?
Biostimulation
What term describes the addition of a nutrient that stimulates a broad substrate-range degradation pathway?
Cometabolism
What term describes specific addition of a known degrading microbe to a contaminated environment?
Bioaugmentation
