As forests change, tree physiology responds to changes in resource demands. The impact of Pinus taeda (loblolly pine) mortality on physiology of successional hardwoods is unknown. Liquidambar syraciflua (sweetgum) and loblolly pine individuals were measured for resource-use during a simulated southern pine beetle mortality event where several pines underwent a girdling treatment. Sweetgum next to untreated pines had significantly higher sapflow every month, markedly throughout post-mortality months. Sapflow and photosynthetic capacity significantly declined in girdled pines before needle discoloration. Nitrogen concentration of senesced pine and sweetgum leaves significantly increased from pre-mortality to post-mortality. Pine mortality led to increases in sweetgum water use and leaf nitrogen content. A shift in species dominance from loblolly pine to sweetgum would reduce water lost by pine transpiration during sweetgum dormancy by approximately 154 mm. These data indicate significant responses to disturbance and seasonal resource demands in this forest type.
| Identifer | oai:union.ndltd.org:MSSTATE/oai:scholarsjunction.msstate.edu:td-1985 |
| Date | 11 August 2017 |
| Creators | Hornslein, Nicole |
| Publisher | Scholars Junction |
| Source Sets | Mississippi State University |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Theses and Dissertations |
Page generated in 0.0052 seconds