Required Practical 5: Mesocosm Flashcards
What are mesocosms?
Enclosed “ecosystems” that allows a small part of a natural environment to be observed under controlled conditions.
What materials can be used to make the mesocosm?
A terrarium is a small transparent container, whether it be glass or plastic, in which selected plants or even animals in some cases are kept and observed.
Building the foundation
Building a foundation
-layer for drainage, add layer of pebbles, gravel or sand etc.
-second thin layer of activated charcoal to prevent mold and help to aerate the soil
-thin cover of sphagnum moss (or organic coffee filter)
-final layer of pre-moistened growing medium
Selecting the right plants
-choose plants that are slow growing and thrive in humidity like ferns, club moss, etc.
-Inspect the plant first to make sure its healthy
Maintaining appropriate conditions
-Place in a location with a continuous source of light
-Make sure there are no experience temperature conditions
-Do not over water, ensure that the humidity etc is adjusted before continuing to water
-As level of soil nutrients decrease, plant growth should slow down
The sustainability of closed mesocosms relies on a steady supply of carbon dioxide for the process of photosynthesis. What type(s) of organism(s) provides that carbon dioxide?
Autotrophs, Heterotrophs and Detritivores
Why are mesocosms an important ecological research tool?
They allow testing of manipulated variables that would be too complex to test in existing ecosystems
A class sets up 24 mesocosms with similar conditions (same type and mass of soil, same number of plant seedlings) and seals them.
Every two weeks, four of the mesocosms are opened, and the soil is discarded and the total dry mass of the plants is determined.
The following results are obtained:
What is a reasonable conclusion?
The productivity of the ecosystem reached a maximum at week 6
A class sets up 24 mesocosms with similar conditions (same type and mass of soil, same number of plant seedlings) and seals them.
Every two weeks, four of the mesocosms are opened, and the soil is discarded and the total dry mass of the plants is determined.
The following results are obtained:
What is a reasonable conclusion?
The productivity of the ecosystem reached a maximum at week 6
