Question

earth as a system practice
i. earth system
consider the diagram of a closed jar terrarium on the right. in a closed terrarium, various types of sand, gravel, and pebbles are layered on the bottom of the jar, followed by soil and activated charcoal. plants and mosses are planted into the soil and provided with enough water to thrive. the jar is then sealed, trapping some air inside and all of the added water inside, and placed in a spot with enough sunlight for plants to perform photosynthesis. this terrarium can be used as a miniature model of the earth system.

1. is this an open or a closed system? explain in terms of matter and energy being able to cross system boundaries.
2. now sort the 12 components of the terrarium into the earth subsystems

subsystem components
geosphere glass container*, sand, clay pebbles
hydrosphere
atmosphere
biosphere

• made of silica sand, soda ash, limestone, dolomite and recycled glass, all of which are minerals derived from the geosphere

1. give an example of a biogeochemical cycle that is happening inside the terrarium. what provides the energy to drive this cycle?

Explanation:

Step1: Determine system type

In a closed terrarium, matter (like water, soil components) does not enter or leave the jar as it is sealed. Energy in the form of sunlight can cross the boundaries to drive processes like photosynthesis. So it is a closed - system as matter is mostly contained and energy can cross the boundary.

Step2: Categorize components into Earth subsystems

• Geosphere: Sand, Clay pebbles, Activated charcoal (derived from natural sources), Gravel, Pebbles, Soil (mineral - rich). The glass container is made from geosphere - derived materials but is an artificial container and not a natural part of the geosphere in the strictest sense, so we exclude it.
• Hydrosphere: Water
• Atmosphere: Air
• Biosphere: Three plants, Mosses

Step3: Identify biogeochemical cycle and energy source

The water cycle is happening inside the terrarium. Water evaporates from the soil and plant surfaces, condenses on the cooler parts of the jar, and then falls back as 'precipitation' onto the soil and plants. The energy to drive this cycle is provided by sunlight which heats the water causing evaporation.

Answer:

1. It is a closed system. Matter is mostly contained within the sealed jar, while energy (sunlight) can cross the system boundaries to drive processes like photosynthesis.

2.

Subsystem	Components
Hydrosphere	Water
Atmosphere	Air
Biosphere	Three plants, Mosses

1. The water cycle is occurring. Sunlight provides the energy to drive this cycle.