PARENT SESSION
Poster Session 20: Invasive Species
Wednesday, August 10, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Soil organic matter composition beneath native and invasive plant species in a peat-forming wetland, New York State.
Yavitt, Joseph*,1, Williams, Christopher2, 1 Cornell University, Ithaca, NY2 Franklin & Marshall College, Lancaster, PA
ABSTRACT- We analyzed soil organic matter (SOM) chemistry and quality from four distinct vegetation zones within a peat-forming wetland in central New York State. Soil cores (30 cm in length) collected in areas dominated by native plant species (Carex lacustris; Juncus effusus), and invasive plant species (Typha latifolia; Lythrum salicaria) were subdivided into 5 cm depth intervals and analyzed by proximate analysis and by lignin oxidation. Soil organic matter quality differed in the surface soil interval among the four vegetation types but differences diminished with increasing soil depth. We found no significant differences in the polar and non-polar soluble carbon compounds among the different vegetation types. Likewise, concentrations of dissolved organic carbon in soil water did not differ among sites and were greater in subsurface soil (13.3 mg C/l at 20 cm depth) than in surface soil (8.6 mg C/l at 5 cm depth). We did find less Klason lignin content of near surface soil from the invasive Typha (533 mg/g + 26) and Lythrum (540 mg/g + 24) sites than from soils beneath native Carex (607 mg/g + 32) or Juncus (610 mg/g + 25). These differences disappeared with increasing soil depth. This pattern in SOM was similar to the Klason lignin content of fresh foliage from all four plant species: Carex = 515 mg/g; Juncus = 500 mg/g; Typha = 369 mg/g; and Lythrum = 402 mg/g. Lignin oxidation chemistry revealed less decomposed lignin (as indicated by the syringyl acid to syringaldehyde ratio from surface soils under invasive species as compared to native species: Carex Ad/Al S = 0.72; Juncus Ad/Al S = 1.19; Typha Ad/Al S = 0.26; and, Lythrum Ad/Al S = 0.41. Our results show that invasive plant species are beginning to leave their chemical imprint on SOM.
Key words: wetland, invasive, soil