Allometry, Morphometry and Soil Characterization of Giant Cane [Arundinaria gigantea (Walt.) Muhl.] Stands in Southern Illinois

Author

Michael Dane Goble, Southern Illinois University CarbondaleFollow

Date of Award

5-1-2013

Degree Name

Master of Science

Department

Forestry

First Advisor

Schoonover, Jon

Abstract

The effectiveness of giant cane [Arundinaria gigantea(Walt.) Muhl.] as riparian buffer vegetation has been demonstrated through research and has gained interest from state and federal agencies to support restoration efforts. Unfortunately, little is known about the physical and chemical properties of the soils below canebrakes and how soil characteristics influence aboveground and belowground biomass production. To determine what physical attributes of the plant influence its success as riparian buffer vegetation and also to determine the interactions with underlying soils, fourteen canebrakes were sampled throughout Southern Illinois. Objective one was to develop an allometric equation to quantify belowground biomass based on aboveground parameters of canebrakes. Previous research found that successful propagation was dependent on rhizome length, the number of internodes and the number of rhizome buds present, but no data exists regarding the yield of rhizomes for a given area. By harvesting all aboveground biomass (culms and leaves) and belowground biomass (roots and rhizomes) to a depth of 25 cm from a 1-m2 plot at each site, morphometric characteristics were quantified and biomass allocation throughout the plant was determined. A significant linear relationship between total aboveground biomass (live and dead) and belowground biomass in giant cane was evident (R=0.865, p<0.001). Although this is a strong relationship, it may be impractical for a manager to harvest, process, and weigh all of the aboveground biomass to speculate the biomass below ground. Therefore, metrics were explored for predicting the length of rhizome, number of rhizome internodes and number of rhizome buds an area will yield using multiple regression and models were developed that estimate these parameters. Using the equation that predicts the number of rhizome buds for a given area, the yield of propagules can then be estimated. Although this equation does not account for all variation of belowground characteristics, it will provide a general guideline for land managers restoring giant cane. The second objective was to estimate biomass allocation of giant cane roots/rhizomes beneath canebrakes by depth (i.e., at 25-cm increments to a depth of 150 cm). Results showed that 67% of giant cane's belowground biomass was within the top 25 cm of the soil profile and accounted for 65% of all belowground biomass encountered at that depth. Giant cane rhizomes were documented to a depth of 51-75 cm deep while cane roots existed in the deepest cores at a depth of 126-150 cm with an average density of 0.08 kg m-3. Giant cane belowground biomass declined with increasing depth, but was still the dominant species at 26-50 cm, comprising 61% of all biomass encountered at that depth. These results support the utility of giant cane as an effective riparian buffer species by increasing the soil porosity and promoting infiltration while contributing a significant source of carbon to the soil profile. Chemical and physical soil properties were measured to determine if they related to canebrake characteristics. Significant correlations were found between various soil properties and canebrake characteristics, implying there is an interaction between giant cane and the underlying soil. Results from this research will improve our understanding of the dynamics of giant cane and supplement existing information to help guide restoration efforts.