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The Multiple Element Limitation in Northern Hardwood Ecosystems (MELNHE) project studies N , P, and Ca acquisition and limitation of forest productivity through a series of nutrient manipulations in northern hardwood forests. This data set includes data testing effects of elevated N and P availability on fine root growth (using ingrowth cores) and biomass in the MELNHE project. Subsets of ingrowth cores were treated with nutrients differing from the plot-scale nutrient treatments to test fine root foraging. Additional detail on the MELNHE project, including a datatable of site descriptions and a pdf file with the project description and diagram of plot configuration can be found in this data package: https://portal.edirepository.org/nis/mapbrowse?scope=knb-lter-hbr&identifier=344 These data were gathered as part of the Hubbard Brook Ecosystem Study (HBES). The HBES is a collaborative effort at the Hubbard Brook Experimental Forest, which is operated and maintained by the USDA Forest Service, Northern Research Station. 

Abstract. Meeting internationally agreed-upon climate targets requirescarbon dioxide removal (CDR) strategies coupled with an urgent phase-down offossil fuel emissions. However, the efficacy and wider impacts of CDR arepoorly understood. Enhanced rock weathering (ERW) is a land-based CDRstrategy requiring large-scale field trials. Here we show that a low 3.44 t ha−1 wollastonite treatment in an 11.8 ha acid-rain-impacted forested watershed in New Hampshire, USA, led to cumulative carbon capture by carbonic acid weathering of 0.025–0.13 t CO2 ha−1 over 15 years. Despite a 0.8–2.4 t CO2 ha−1 logistical carbon penalty from mining,grinding, transportation, and spreading, by 2015 weathering together withincreased forest productivity led to net CDR of 8.5–11.5 t CO2 ha−1. Our results demonstrate that ERW may be an effective, scalableCDR strategy for acid-impacted forests but at large scales requiressustainable sources of silicate rock dust. 

Abstract. Meteoric 10Be (10Bemet) concentrations insoil profiles have great potential as a geochronometer and a tracer of Earthsurface processes, particularly in fine-grained soils lacking quartz thatwould preclude the use of in situ produced 10Be (10Bein situ). Oneprerequisite for using this technique for accurately calculating rates anddates is constraining the delivery, or flux, of 10Bemet to a site.However, few studies to date have quantified long-term (i.e., millennial)delivery rates, and none have determined a delivery rate for an erodingsoil. In this study, we compared existing concentrations of 10Bein situ with new measurements of 10Bemet in eroding soils sampledfrom the same depth profiles to calibrate a long-term 10Bemetdelivery rate. We did so on the Pinedale (∼ 21–25 kyr) and BullLake (∼ 140 kyr) glacial moraines at Fremont Lake, Wyoming(USA), where age, grain sizes, weathering indices, and soil properties areknown, as are erosion and denudation rates calculated from 10Bein situ. After ensuring sufficient beryllium retention in each profile,solving for the delivery rate of 10Bemet, and normalizing forpaleomagnetic and solar intensity variations over the Holocene, we calculate10Bemet fluxes of 1.46 (±0.20) × 106 atoms cm−2 yr−1 and 1.30 (±0.48) × 106 atoms cm−2 yr−1 tothe Pinedale and Bull Lake moraines, respectively, and compare these valuesto two widely used 10Bemet delivery rate estimation methods thatsubstantially differ for this site. Accurately estimating the 10Bemetflux using these methods requires a consideration of spatial scale andtemporally varying parameters (i.e., paleomagnetic field intensity, solarmodulation) to ensure the most realistic estimates of10Bemet-derived erosion rates in future studies.