Johnson 1
Kelsey Johnson
Environmental Science
6/12/12
Species Diversity Mini Write Up
Natural systems contain species populations including the insect community. Species
populations interact with one another to form sturdy functioning communities through which
matter and energy flow. The disruptions of these communities such as the insect community can
result in declines in species richness which alters the flow of matter and energy. Biodiversity is
important because of the variety that exists within the insect community to function properly.
The losses of this have concluded in losses of economic and as well as benefits that were part of
the original habitat they may never be recovered.
The materials we used in this species diversity experiment include an insect net to catch
the bugs, datasheets to record the different type of bugs we found and how many, and the pens
or pencils for writing down the results. We conducted the experiment by describing the habitat,
sweeping the vegetation ten times to catch the bugs and then counted and categorized the insects
collected and recorded it on the datasheets. Calculating the species diversity for each habitat was
based on the total number of insects collected in habitat one and habitat two using the formula,
H= (Pi/InPi/). Pi equaled the proportion of species I and (InPi) equaled the absolute value of the
natural log of species i.
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Habitat 1
Insect Species
Number Pi
Spider
2
Gnats
30
Flys
10
Moth
1
Lime Spider
1
Red Beatle
1
Ant
3
Fire Ant
2
Sum
50
0.04
0.6
0.2
0.02
0.02
0.02
0.06
0.04
1
In(Pi)
Pi*In(Pi)
3.2189
0.13
0.5108
0.31
1.6094
0.32
3.912
0.08
3.912
0.08
3.912
0.08
2.8134
0.17
3.2189
0.13
23.1074 H=1.3
0.375
0.025
0.525
0.05
0.025
In(Pi)
Pi*In(Pi)
0.9808
0.37
3.6889
0.09
0.6444
0.34
2.9957
0.15
3.6889
0.09
Habitat 2
Insect Species
Number Pi
Green Beatle
15
Butterfly
1
Green Bug
21
Sugar Ant
2
Lady Bug
1
Sum
40
1
11.9987 H=1.04
Values close to 0 imply low diversity and values approaching 4.6 imply high diversity.
We calculated the table and outcomes using the Shannon-Weiner Diversity Index. The results
revealed that Habitat 1 was a more diverse field than Habitat 2. Habitat 1’s H equaled 1.3
whereas Habitat 2’s H equaled 1.04 suggesting that Habitat 1’s H number being high would be
the more diverse out of these two habitats. Habitat one had more activity of bugs going on
because there were more characteristics taking place such as green grass, a soccer goal, a bench,
a fence, and a trash can with tall grass. Habitat 2 took place in a more natural environment with
taller grass, a trail, bamboo trees, and regular trees as well. The trash can is where we caught
Johnson 3
most of the bugs and I think because it was where people walk around there is food and I think it
attracts more of the bugs to that specific area.