Data from: Restoration of riparian forest cover increases carbon stocks in the Pacific Northwest

Reforestation of degraded riparian areas provides climate mitigation
benefits through increased carbon storage. In recent decades, riparian
reforestation has accelerated in the Pacific Northwest (PNW) of the United
States, primarily aiming to restore ecosystem functions and associated
benefits, but few studies have evaluated riparian planting C sequestration
and storage, particularly in highly productive wet riparian ecosystems
like the PNW.  Using these plantings as a ‘natural experiment’,
we assessed C storage in woody vegetation (trees and shrubs) and soils
across a chronosequence of PNW riparian reforestation sites, and
non-forested riparian baseline sites, representing the pre-planting
condition. These data were used to evaluate changes in C storage with
planting age and identify key covariates affecting C storage in plants and
soils and their relationship with planting age across a ~430 km
latitudinal gradient in western Oregon, USA.   
Sites were distributed across 3 ecoregions, the Willamette Valley, the
Pacific Northwest Coast, and the Klamath Mountains. The 43 studies sites
were either non-forested or planted 5 -27 years before field data
collection. The dataset includes biophysical properties of each site, as
well as measurements of trees, shrubs, and soils which were used to
calculate C storage at each plot and site. Sites stored between 38.3 –
511.1 Mg C per hectare, and carbon storage generally increased with
planting age. The majority of site carbon was stored in soils; however, C
storage differed more across planting ages for trees and the understory
than for soil.