| Title: |
Defoliation severity is positively related to soil solution nitrogen availability and negatively related to soil nitrogen concentrations following a multi-year invasive insect irruption |
| Authors: |
Conrad-Rooney, Emma; Barker Plotkin, Audrey; Pasquarella, Valerie J; Elkinton, Joseph; Chandler, Jennifer L; Matthes, Jaclyn Hatala |
| Contributors: |
Atkins, Jeff; Wellesley Science Center Summer Research Program; Frost Endowed Environmental Science Studies Fund; U.S. National Science Foundation; Harvard Forest REU program |
| Source: |
AoB PLANTS ; volume 12, issue 6 ; ISSN 2041-2851 |
| Publisher Information: |
Oxford University Press (OUP) |
| Publication Year: |
2020 |
| Description: |
Understanding connections between ecosystem nitrogen (N) cycling and invasive insect defoliation could facilitate the prediction of disturbance impacts across a range of spatial scales. In this study we investigated relationships between ecosystem N cycling and tree defoliation during a recent 2015–18 irruption of invasive gypsy moth caterpillars (Lymantria dispar), which can cause tree stress and sometimes mortality following multiple years of defoliation. Nitrogen is a critical nutrient that limits the growth of caterpillars and plants in temperate forests. In this study, we assessed the associations among N concentrations, soil solution N availability and defoliation intensity by L. dispar at the scale of individual trees and forest plots. We measured leaf and soil N concentrations and soil solution inorganic N availability among individual red oak trees (Quercus rubra) in Amherst, MA and across a network of forest plots in Central Massachusetts. We combined these field data with estimated defoliation severity derived from Landsat imagery to assess relationships between plot-scale defoliation and ecosystem N cycling. We found that trees in soil with lower N concentrations experienced more herbivory than trees in soil with higher N concentrations. Additionally, forest plots with lower N soil were correlated with more severe L. dispar defoliation, which matched the tree-level relationship. The amount of inorganic N in soil solution was strongly positively correlated with defoliation intensity and the number of sequential years of defoliation. These results suggested that higher ecosystem N pools might promote the resistance of oak trees to L. dispar defoliation and that defoliation severity across multiple years is associated with a linear increase in soil solution inorganic N. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1093/aobpla/plaa059 |
| DOI: |
10.1093/aobpla/plaa059/34300176/plaa059.pdf |
| Availability: |
https://doi.org/10.1093/aobpla/plaa059; http://academic.oup.com/aobpla/advance-article-pdf/doi/10.1093/aobpla/plaa059/34300176/plaa059.pdf; http://academic.oup.com/aobpla/article-pdf/12/6/plaa059/40326917/plaa059.pdf |
| Rights: |
http://creativecommons.org/licenses/by/4.0/ |
| Accession Number: |
edsbas.8B47C03C |
| Database: |
BASE |