Popsicle sticks and filter paper decomposition in forest soil

Presented by REU Amos Lim Zhen Yu

SUNY-ESFSenior year undergraduate

Introduction• Decomposition def-: Break down and decay of organic matter

• It affects the nutrients availability in the forest floor and soil

Recycled nutrients will be added to the forest floor and soil

• Potential carbon source in the forest. Beginning of food chains: Fungi/bacteria > worms > birds

• Main polymers in plant fiber including: cellulose, hemicellulose, and lignin.

Nutrients effect on decomposition

• In my project, I focus on relationships between decomposition rate and addition of nutrients including: Nitrogen (N), Phosphorus (P), and Calcium (Ca) in the forest soil.

• Past studies shown P and Ca potentially accelerate the decomposition but not the extent of decomposition (Reid 1983).

Nitrogen and decomposition

• Nitrogen (N) causes inhibition of plant fiber degradation, called N-repression.

Nitrogen and decomposition

Some complexity in decomposition

• Different N source can have extremely different effect

• Example: Different N effect on white rot fungi Phanerochaete chrysosporiumt decomposition

Urea supplements (1% added N) strongly inhibited lignin degradation and weight loss.

The complex nitrogen sources peptone stimulated lignin degradation and weight loss.

NH4Cl had intermediate effects.

What is available in Bartlett Experimental Forest?

• Different stand ageYoung (age ~20), Old ( ~120)

• Fertilized plotsN, P, N+P and Control in each stand

We have one Ca plot in each young and old stand

Methods

• I compare the decomposition rate of fertilized plots and the control plots to see the differences.

Methods

• I chose to look at decomposition using filter paper and popsicle sticks.

The cellulose and lignin in daily life

~1.03g ~ 1.3±0.3 g

Duration for my studies

I will bury and retrieve it after 3 months

Weight lost over 3 months period tell us the decomposition rate of cellulose.

Duration for my studies

I will bury and retrieve it in a year or 2 year period.

Weight lost over time tell us the decomposition rate of lignin.

Systematic locations

Hypothesis

• I hypothesize that the cellulose/lignin decomposition rate would be lower when concentration of Nitrogen is higher in the microenvironment of the cellulose/lignin. The cellulose/lignin decomposition rate would be higher when concentration of Ca is higher in the microenvironment of the cellulose/lignin. Therefore I expect to see significantly lower decomposition in N, and N+P fertilized stands in the end of the studies. Where the Ca and P does not affect the decomposition result.

Hypothesis

Higher Nitrogen concentration → lower decomposition

Higher Phosphorus concentration → higher decomposition

Higher in Both Nitrogen and Phosphorus →lower

Higher Ca concentration → higher decomposition

Some other problems in the past studies

• Decomposition rate varies a lot. • Decomposition takes a LONG time.• Decomposition related to microenvironment. • Microorganism involved in decomposition is

not well studied enough for us to understand decomposition process.

Importance of my project

• To study decomposition with limited funding.

• To give us directions on future studies.

• To see if there’s a general pattern in our experimental forest.

Acknowledgement

• All the Phd titled, in ShoeString Project• And all the rootmates.

& Russell

References• Berg, B., & Laskowski R. (2006). Advances in Ecological

Research Volume 38: Litter decomposition: A guide to carbon and nutrient turnover. San Diego: Elseview Academic Press.

• Binkley, D. (1983). Does Forest Removal Increase Rates of Decomposition and Nitrogen Release?. Amsterdam, The Netherland: Elsevier Science Publisher B.V.. For. Ecol. Manag., 229-233.

• Reid, I., D. (1983). Effects of Nitrogen Supplements on Degradation Wood Lignin and Carbohydrate Components by Phanerochaete chrysosporium. Saskatoon, Saskatchewan, Canada. Applied and Environmental microbiology,.. 830-837.