differences in soil organic matter and soil texture in newly constructed experimental wetlands...

Differences in soil organic matter and soil texture in

newly constructed experimental wetlands

Catherine BodnarSam Merrett

Becca Brooke

EDIC Wetland Project

1No

Planting

2Low

IntensityPlanting

3High

IntensityPlanting

4No

Planting

5Low

IntensityPlanting

6High

IntensityPlanting

The objective of the EDIC study is to determine which of three planting treatments best restores

function in constructed wetlands

Study Objectives:

Collect baseline data on SOM and texture to assess future effects of treatments

Determine how construction affected SOM and texture

The Importance of Texture and Soil Organic Matter

Soil Organic Matter

Water Holding Capacity Cation Exchange Capacity Soil Development Rates

Texture

Water holding capacity Nutrient content Soil Organic Matter

Both soil texture and soil organic matter are important to other soil properties and can be a good indicator of how an ecosystem is functioning

Methods: Sample Collection

6 wetland cells 225 Ft. X 115 Ft.

Data set #1: SOM = Green X’s

12 samples/cell 36 cores/cell

Texture = yellow circles 4 samples/cell 12 cores/cell

Data set #2: SOM = Black Oval

5 samples/cell 15 cores/cell

BA C D E F G1

2

4

5

6

7

8

3

Methods: Sample Analyses

• Texture• Removed 50 g from oven-dried

sample• Mixed in blender to separate soil

particles• Took hydrometer readings to estimate

percentages of sand, silt, and clay

• Soil Organic Matter• Hammered baked soil for further homogenization• Weighed soil and crucible• Incinerated at 400ºC• Used difference in weight of soil before and after incineration to estimate percent SOM

*statistical difference in silt and clay %, not in sand %

*East to West gradient

Percent Sandy = 0.6692x + 12.928

R2 = 0.2278

0

5

10

15

20

25

30

35

40

45

50

Wetland 1 Wetland 2 Wetland 3 Wetland 4 Wetland 5 Wetland 6

perc

ent of to

tal part

icle

s

Percent Silty = 1.7488x + 35.714

R2 = 0.7417

0

5

10

15

20

25

30

35

40

45

50

Wetland 1 Wetland 2 Wetland 3 Wetland 4 Wetland 5 Wetland 6

per

cent of to

tal p

articl

es

Percent Clay y = -2.418x + 51.358

R2 = 0.9693

0

5

10

15

20

25

30

35

40

45

50

Wetland 1 Wetland 2 Wetland 3 Wetland 4 Wetland 5 Wetland 6

per

cent of to

tal p

articl

es

SAND

SILTCLAY

*Statistical difference between cells

*East to west SOM gradient

***Average SOM per Cell *****

0

1

2

3

4

5

6

7

1 2 3 4 5 6

*Wetland **

% S

OM Data Set #1

Data Set #2

Linear (Data Set #1)

Linear (Data Set #2)

SOM and Texture Distribution

1 2 3 4 5 6

There IS a statistically significant difference forSOM, Silt and Clay between the western and

eastern groups, and NOT among group members

West Group East Group

Implications1 4

Researchers will have to consider:*There is statistical difference between some replicates

*Measured variables effect other soil properties

No Planting

2 5

Low Intensity Planting

3 6

High Intensity Planting

1 4

No Planting

2 5

Low Intensity Planting

3 6

High Intensity Planting

SOM and Silt

Clay??

Wetland Construction Didn’t Change Measured Variables

Soil Survey Data(texture)

Sabel et. al.(SOM)

MkA: Mahoning-Tiro silt loamTrA: Trumball

Special Thanks To:

•John Petersen

•Brad Masi

•Josh Smith