Field Study: Caswell State Park

8/14/2019 Field Study: Caswell State Park

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Caswell Memorial State Park Field Study & Lab

by Luke Basaca

November 3rd, 2008

IB Environmental Systems & Societies

Mr. WedelWord Count: 3037


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Aim of the Lab:

How healthy is an ecosystem, based solely on biotic and abiotic factors?

Background

Caswell Memorial State Park, located on the banks of the Stanislaus River near Ripon,

California, was where the field study was conducted. The state park itself is unique in the sense

that it has certain characteristics that set it apart from other state parks. Caswell was founded in

1958 by local landowners who wanted to save this piece of land from development; it eventually

opened in 1958, its size initially 134 acres, but with additional donations increased to its current

size of 258 acres. Within the state park resides many qualities unique to not only the area but the

world. Caswell includes the largest collection of Valley Oak Trees within the Central Valley. It

also is the home of the elusive Riparian Brush Rabbit, a species of rabbit not found anywhere

else in the world.

Caswell State Park's main reason for being such a unique place within the Central Valley

is mainly due to the fact that it represents a very important and somewhat uncommon ecosystem,

called a riparian woodland or zone. Riparian woodlands are usually considerably smaller in size

compared to surrounding ecosystems. However, they are typically more ecologically diverse

with a larger amount of different species of both plants and animals residing within its'

boundaries. Riparian ecosystems are an important source of food, shelter, and resources for the

many animals not only residing in it, but also for animals surrounding it. The ecosystem itself

also serves as a type of filtration system for the rivers and streams crossing through it and as a

type of flood control system, controlling and slowing down the flow of water in a river.

Due to riparian ecosystems being typically small in size and relatively close in proximity

to major rivers and streams, they are usually most affected by ongoing human development and


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alteration. Farming and construction has been a great issue in the Central Valley's riparian

ecosystems, contributing to the shrink of the number of remaining woodlands. As the field study

was conducted, great care was taken to make sure not to disturb the habitat of the native plants

and animal species. When any disturbances did occur, however, great care and effort was taken

in order to reverse any changes.

The healthiness of a riparian woodland ecosystem, like any ecosystem, relies on two

factors: abiotic and biotic. Abiotic factors are the non-living elements that affect an ecosystem.

Examples of abiotic factors measured in the field study and lab were light levels, temperature,

moisture levels, and soil content (pH; potassium, nitrate, and phosphorus levels). Biotic factors,

on the other hand, is quite the opposite; they are the living components of an ecosystem. Biotic

factors measured in the lab included the abundance, diversity, and density of biomass.

Purpose:

To observe and explain the biotic and abiotic characteristics of a Reparian Woodland in

order to determine it's healthiness.

Hypotheses:

1. If the abiotic factors are helpful to organisms in an ecosystem, then these organisms will

be healthy and numerous.

2. If the organisms in an ecosystem are numerous and equal, then the ecosystem itself is

healthy.


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Materials:

-Group Field Equipment -Group Lab Equipment

1 data sheet tongs

1 Ruler electronic balances

4 stakes oventwine aluminum pan sheets

4 meter sticks

1 compass1 chemical test kits

1 thermometer

1 soil thermometer1 light meter

1 soil auger

3 ziploc bags1 distilled water jug

1 insect netdividing tape

measuring tape4 popsicle sticks

camera (optional)

Procedures:

1) equipment setup:

1. The ziploc bags were weighed and labeled.2. Four popsicle sticks were obtained and were formed into a square measuring 0.1 m2.

3. All Group Field Equipment, including the sampling quadrat square, was placed into large

bag.

2) data sheet:

3. A data sheet was created that recorded all the information from the field needed for the

lab. Include:light levels (in foot candles)

temperature (in 0C)

1.0 meters above ground level0.1 meters below ground level

at ground level

soil contents: pH levels

phosphate levels

nitrate levels

potassium levels

abundance (number of species)

2. Also included were measurements while in the lab:

total biomass (wet and dry)


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moisture level (soil and organic material)

diversity levels (using the Simpson diversity Index)

3) Site Selection:

1. A 100 meter transect line that ran north/south was created using a tape measure and

compass.2. Tape was used to mark the transect line (see figure 1)

Figure 1:

3. Within three points along the transect, three stage quadrats were then established,

measuring 10 m2.4. The boundaries of the stage quadrats were marked by dividing tape.

5. Within each stage quadrat, smaller group quadrats, measuring 1 m2, were chosen at

random (ex: throw square over shoulder without looking, throw square with eyes closed,etc.).

6. Four meter sticks created into a square marked a chosen group quadrat.

7. A sampling qaudrat was chosen at random by throwing the 10 cm2 popsicle square intothe group quadrat. (see figure 2)

4) Field Measurements:

Sunlight

1. A light meter was obtained and should have been set to the sun and highintensity setting.

2. You were to wait until the time is at 11:50 am, or solar noon at a randomly

chosen spot within your group quadrat, at ground level. (see figure 3)

3. You were then to read the measurements at 11:50 am at ground level and recordthem in foot candles.

Temperature:

1.0 meters above and at ground level:

1. A regular thermometer and meter stick was obtained.

2. Sampling site was then chosen at random and the meter stick was thenplaced in the spot.(see figure 4):

3. The temperature was taken at solar noon, or 11:50 am, in degrees Celsius.

4. Temperatures were recorded onto data sheet.

0.1 meters below ground level :1. A soil thermometer was used to take the temperature.

2. The soil thermometer spike was marked at 10 centimeters, or .01 meters,with a sharpie.

3. Like the regular thermometer reading, the site was chosen at random

within the group quadrat.

4. The soil thermometer was then driven into the ground until the sharpiemark wasn't visible.(see figure 5)

5. The temperature was taken at solar noon, or 11:50 am, in degrees Celsius.

6. Temperature was recorded onto data sheet.


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Soil Contents (pH, nitrate, phosphate, and potassium levels) :

1. A soil auger was obtained and used to take a soil sample within a random spot inthe group quadrat.

2. Four soil samples from the soil auger were obtained.

3. A chemical test set was then obtained.(see figure 6)

4. Tests were done for pH, phosphates, nitrates, and potassium levels in accordanceto the instructions provided inside the chemical test set.

5. The measurements were recorded.

6. The remaining soil sample was put into a pre-weighed ziploc bag

Abundance of individuals:

1. Within the group quadrat, five sampling quadrats were created at random.

2. A count of every individual plant species was then done in each sampling quadrat.3. The number of each individual plant species was also done.

4. Species classified into A, B, C categories (ex. Species A)

5. Recorded data onto data sheet.6. Biomass from each sampling quadrat was collected. (see figure 7)

7. Two pre-weighed ziploc bags were used to collect the biomass.5) Lab measurements (see figure 8) :

Moisture level (soil and biomass)1. The pre-weighed ziploc bags containing the soil sample and biomass was weighed

and the weights were recorded.

2. An aluminum pan was obtained and weighed; pan's weight was then marked.3. The aluminum pan was then filled with the biomass and soil samples that were

inside the ziploc bags.

4. The aluminum pan were weighed again and marked.5. An oven was pre-heated to 450 degrees Fahrenheit (232.22 degrees Celsius).

6. Aluminum pan was placed into oven for 24 hours.

7. After 24 hours, the aluminum pan with soil was reweighed and recorded.8. The moisture level of the soil was obtained by subtracting the weight of the bakedsoil(X) from the original weight(Y), then dividing it by the original weight(X):

X-Y

X x 100 = moisture level (in percent)9. Repeated steps 1-8 for biomass.

Total dry biomass:

1. An electronic balance was used to weigh the two biomass-filled ziploc bags.2. The difference between the total weight of each bag and the weight of each

individual bag provided the weight of the total wet biomass in each bag.

3. An aluminum pan was obtained and weighed; pan's weight was then marked.

4. The aluminum pan was then filled with the biomass that was inside the ziplocbags.

5. Aluminum pans were weighed again and marked.

6. An oven was pre-heated to 450 degrees Fahrenheit (232.22 degrees Celsius)7. Aluminum pan placed into oven for 24 hours.

8. Aluminum pan was reweighed and recorded after 24 hours.


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Calculating Diversity Level

1. Diversity level was measured using the Simpson Reciprocal Index:

n = the total number of organisms of a particular speciesN = the total number of organisms of all species

2. The total number of organisms were determined from both the group quadrat and

overall number from all group quadrats.

3. The larger the answer, the lower the diversity level.

Calculating Density and Relative Density

Density (Di):1. Density was found using the data gathered for finding the number of all

species present, group quadrat and overall using the equation:

ni

A

ni = amount of an individual speciesA = area the individual of species inhabits

Relative Density (RDi)

1. Relative density found using the data gathered for finding the number of all

species present, group quadrat and overall using the equation:Di

Di

Di = density of a species

Di = total density in a given area for all species


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Data:

1) Observations

Quadrat Coordinates

-Group Quadrat (4.5 Meters/2 Meters)

Figure 10: Stage and Group Quadrat coordinates

Site Description

3 living trees in stage quadrat

detrius material (plant leaves, twigs, grasses) all over ground

partial sunlight due to tree canopy

soil rich in detrius material


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2) Data Tables and Graphs

Table #1: Abiotic Factors:

Light Levels:(taken at 11:50

am)

1500

foot candles

N/A N/A N/A

Temperature:

(taken at 11:50am)

1.0 meters above

ground level:

25oC

0.1 meters below

ground level:17oC

@ ground level:

25oC

N/A

Soil Composition pH:

6.0

Phosphates:

low

Nitrates:

low

Potassium:

medium to low

Table #2: Bag Weights

Bags Weights (in g)

with bag

Bag weights Weights (in g) without bag

A (biomass) 25.95 g 7.56 g 18.39 g

B (soil) 17.60 g 7.48 g 10.12 g

C (biomass) 11.79 g 7.76 g 4.03 g

Table #3: Biotic Factors (number of species present)

Species Number within Group Quadrat Overall Number (class data)

A (Johnson Grass) 85 136

B (Crab Grass) 3 12

C (Blackberry) 0 23

D (Valley Oak Tree) 9 9

Total: 97 185

Table #4: Percentage composition of species

Species Percentage (Group Quadrat) Overall Percentage (class data)

A 87.8% 73.53%

B 3% 9.18%

C 0% 12.43%

D 9.2% 4.86%

Total Percentage: 100% 100%


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Graph #1: Percentage Composition of Species (Group Quadrat)

Graph #2: Percentage Composition of Species (Class Data)

A (JohnsonGrass)

B (Crab Grass)

C (Blackberry)

D (Valley OakTree)

A (JohnsonGrass)

B (Crab Grass)

C (Blackberry)

D (Valley OakTree)


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3) Simpson Diversity Index:

Table #5 & Math: Diversity Index (group quadrat)

Species Number (n) n(n-1)


B (Crab Grass) 3 6

C (Blackberry) 0 0


Total (N) 97

Total:

7218

97(96) 9,312

D = 7,218 = 7,218 = 1.29

Table #6 & Math: Diversity Index (class data)

Species Number (n) n(n-1)


B (Crab Grass) 12 132

C (Blackberry) 23 506


Total (N) 185

Total:

19070

185(184) 34,040

D = 19,070 = 19,070 = 1.78


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4)Density and Relative Density (Di & RDi)

Density (Di):

Table #7 & Math: Density Data

Species ni (group quadrat) ni (class data) A (group quadrat) A (class data)

A (Johnson

Grass)

85 136 0.1 m2 6 m2

B (Crab Grass) 3 17 0.1 m2 6 m2

C (Blackberry) 0 23 0.1 m2 6 m2

D (Valley OakTree)

9 9 0.1 m2 6 m2

Example:

Species A (group quadrat & overall)

Group Quadrat:

85Di = 0.1 m2 = 850 Di

Overall (Class Data)

136Di = 6 m2 = 22.66 Di

Table #8: Density (group quadrat & overall class data)

Species Di (Group Quadrat) Di (Class Data)

A (Johnson Grass) 850 Di 22.66 Di

B (Crab Grass) 30 Di 2.83 Di

C (Blackberry) 0 Di 3.83 Di

D (Valley Oak Tree) 90 Di 1.5 Di


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Relative Density (RDi):

Table #9 & Math: Relative Density Data

Species Di (groupquadrat)

Di (class data) Di (groupquadrat)

Di (class data)

A (Johnson

Grass)

850 Di 22.66 Di 970 Di 30.82 Di

B (Crab Grass) 30 Di 2.83 Di 970 Di 30.82 Di

C (Blackberry) 0 Di 3.83 Di 970 Di 30.82 Di

D (Valley OakTree)

90 Di 1.5 Di 970 Di 30.82 Di

Example:

Species A (group quadrat & overall)

Group Quadrat850 Di

970 Di = .878 RDi

Overall (Class Data)22.66 Di

30.82 Di = .7352 RDi

Table #9: Relative Density (group quadrat & overall class data)

Species RDi (Group Quadrat) RDi (Class Data)

A (Johnson Grass) .878 RDi .7352 RDi

B (Crab Grass) 0.03 RDi 0.0918 RDiC (Blackberry) 0 RDi .1242 RDi

D (Valley Oak Tree) 0.092 RDi 0.0486 RDi

5) Moisture levels:

Table #10 & Math: Moisture Level Calculations

X (weight, in g, before baking) Y (weight, in g, after baking)

P1: biomass 4.73 g 4.14 g

P2: soil 17.56 g 14.21 g

P1: 4.73g 4.14g

4.73 g x 100 = 12.4 %

P2: 17.56g 14.24g17.56 g x 100 = 19 %


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Conclusion and Evaluation:

The original purpose of this lab was to To observe and explain the biotic and abiotic

characteristics of a Reparian Woodland in order to determine it's healthiness.. Our original

hypotheses were that: 1. If the abiotic factors are helpful to organisms in an ecosystem, then

these organisms will be healthy and numerous; 2. If the organisms in an ecosystem are

numerous and equal, then the ecosystem itself is healthy.. This hypotheses were actually proven

while doing both the field study and the lab in a more negative way.

Solid pattens were found while calculating all the measurements. Both the class data and

the individual group quadrat data for diversity and relative density seemed to be quite similar.

Both showed that species A (Johnson Grass) took up a majority of the entire plant population

within both the group quadrat and the other 6 group quadrats of other groups. Diversity levels in

both the group data and the overall class data were very similar, both saying diversity levels in

the area are low. This may be connected to the fact that Johnson grass may be better suited to

grow in an environment with partial sunlight, due to the tree coverage, than the other species

present like blackberries, which were absent in our data and only 9 recorded as a whole. Johnson

grass was numerous in numbers, but compared to the other plant species in the area, it

dominated. Johnson grass took 87.8 % of the total count of species in the group data and 73.53

% in the overall data, showing a overwhelming dominance of that particular plant species in the

area. This led to a lower diversity index showing this site was actually very unhealthy. Soil

content also showed low nitrate, phosphate, and potassium levels, indicating soil with a low

amount of nutrients for a diverse amount of plants, possibly inhibiting different kinds of plant

species growing in the area . With both abiotic and biotic factors combined, the data showed that

the site was in fact very unhealthy.


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The measurements and data obtained in both the field study and the lab showed there

have might been some room of errors and mistakes. For instance, while taking the measurements

for solar noon, the switch was mistakenly turned to florescent instead of the required sun and

high intensity setting. Conversion of the data was then required when we returned back to

school and did the lab measurements. Another possible mistake was when the biomass and soil

samples were collected. The soil sample, for example, was poor due to an object obstructing the

soil auger while it was in the ground. The collection of biomass may have also not have been all

that random, mainly due to us looking as we threw the sampling quadrat square onto the ground.

This factor could have affected the density, relative density, and diversity indexes of all the plant

species. It was also strange that the class data for collected plant species was just only 185, out of

6 separate groups. Our group collected 97, or roughly 52 % of all the recorded species population

count.

An obvious improvement that could be done, if we ever did a similar lab again, would be

to simply double-check the data and compare it to other groups in the same area. This way we

could see any inconsistencies with any of our data and act accordingly to fix it. Another

improvement that could be done is to repeat certain steps that may have been failures at first. For

example, if the soil sample was poor in quality, another one could have been done by simply

picking a different sampling quadrat at random. Lastly, one major improvement that needs to be

done in not just this lab but in any lab is to make sure each lab group does each step. The

inconsistency of the number of species counted could be avoided next time by assigning each

group a specific species to look for and record.

If further investigation was done in this same lab, I would suggest a few things to

challenge our current hypotheses. To diversify our data, we could go to Caswell at different


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times of the year, comparing the data and concluding whether if abiotic and biotic factors are

consistent throughout the year. Another suggestion is to go to another test site, possibly ones

totally unrelated to riparian woodlands entirely to compare whether if all ecosystems share

similar biotic and abiotic characteristics or are different in some ways.


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Work Cited Page

http://www.parks.ca.gov/?page_id=557. Caswell Memorial State Park. Accessed 9-28-08

www.yelp.com/biz/caswell-memorial-state-park-ripon. : Caswell Memorial State Park.

Accessed 9-28-08

http://en.wikipedia.org/wiki/Riparian. Riparian zone. Accessed 9-29-08
http://www.parks.ca.gov/?page_id=557http://www.parks.ca.gov/?page_id=557http://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://en.wikipedia.org/wiki/Riparianhttp://en.wikipedia.org/wiki/Riparianhttp://www.parks.ca.gov/?page_id=557http://www.yelp.com/biz/caswell-memorial-state-park-riponhttp://en.wikipedia.org/wiki/Riparian

Documents

Field Study: Caswell State Park