Lithosphere Rocks, Nutrients, & Soils
Lithosphere Objectives:
- Explain the significance of bacteria in the nitrogen cycle.
- Describe impacts on terrestrial ecosystems, including wind and soil erosion.
The lithosphere includes layers of rocks and is the sink for many nutrients.
Most of the active nutrient cycling is occurring in the outer crust although volcanic activity can bring nutrients to the surface.
Nitrogen
The primary sink for nitrogen is the _________.
Nitrogen also plays important roles in the water and within soils.
From this video, which organisms are key in transforming atmospheric nitrogen into a molecular form that can be used by other species?
If you set up a fish tank, or in this example a freshwater shrimp tank, it is critical that bacterial colonies establish to break down the nitrogen molecules from animal excretions and decaying plants. Accumulating ammonia can be deadly and only detectable through water testing.
In many cases it is a good idea to start with a small number of plants and animals until the bacteria transfer in from the air and establish in number. Another possibility is to transfer bacteria-rich sediment and/or plants from another tank.
In this tank, bacteria are primarily located in the sediment and on the surface of the freshwater aquatic plants.
In this tank the bacteria, along with green photosynthetic algae, are abundant in the water column.
Impacts on Terrestrial Ecosystems
Wind can have a significant impact on species.
Wind can increase water loss, erode at plant structures, and drop temperature barriers around a plant.
Wind can also increase rates of soil erosion.
Plants in windy habitats have structural features that reduce exposure.
These are similar to adaptations plants have in cold habitats.
Conifer needles and cactus needles are both examples of leaf shapes that reduce exposure to harsh environmental conditions, including extremes in temperature.
Pines that have evolved in windy coastal environments over time have a different growth form than pines living on central mountains.
Check your knowledge. Can you:
- Explain the significance of bacteria in the nitrogen cycle?
- Describe impacts on terrestrial ecosystems, including wind and soil erosion?
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Biosphere Guide Contents
This guide and corresponding lecture material are assessed on the weekly quiz.
Module 1
Field & Lab
This Guide
Biosphere
