title: Persistent reduced ecosystem respiration after insect disturbance in high elevation forests.
abstract: Amid a worldwide increase in tree mortality, mountain pine beetles (Dendroctonus ponderosae Hopkins) have led to the death of billions of trees from Mexico to Alaska since 2000. This is predicted to have important carbon, water and energy balance feedbacks on the Earth system. Counter to current projections, we show that on a decadal scale, tree mortality causes no increase in ecosystem respiration from scales of several square metres up to an 84 km(2) valley. Rather, we found comparable declines in both gross primary productivity and respiration suggesting little change in net flux, with a transitory recovery of respiration 6-7 years after mortality associated with increased incorporation of leaf litter C into soil organic matter, followed by further decline in years 8-10. The mechanism of the impact of tree mortality caused by these biotic disturbances is consistent with reduced input rather than increased output of carbon.
authors.affiliation: School of Natural Resources and the Environment, University of Arizona, Biological Sciences East, Tucson, AZ 85721, USA. davidjpmoore@email.arizona.edu
authors.forename: David J P
authors.initials: DJ
authors.lastname: Moore
authors.forename: Nicole A
authors.initials: NA
authors.lastname: Trahan
authors.forename: Phil
authors.initials: P
authors.lastname: Wilkes
authors.forename: Tristan
authors.initials: T
authors.lastname: Quaife
authors.forename: Britton B
authors.initials: BB
authors.lastname: Stephens
authors.forename: Kelly
authors.initials: K
authors.lastname: Elder
authors.forename: Ankur R
authors.initials: AR
authors.lastname: Desai
authors.forename: Jose
authors.initials: J
authors.lastname: Negron
authors.forename: Russell K
authors.initials: RK
authors.lastname: Monson
mesh_terms: D028202:Abies; D000531:Altitude; D000818:Animals; D002244:Carbon / Q000378:metabolism*; D002245:Carbon Dioxide / Q000032:analysis; D001517:Coleoptera; D003120:Colorado; D017753:Ecosystem; D009026:Mortality; D028223:Pinus; D018515:Plant Leaves / Q000378:metabolism; D012987:Soil; D014197:Trees
chemical_list: D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon