English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Plants and soil microbiota play an active role in rock weathering and\udpotentially couple weathering at depth with erosion at the soil surface. The\udnature of this coupling is still unresolved because we lacked means to\udquantify the passage of chemical elements from rock through higher plants. In\uda temperate forested landscape characterised by relatively fast\ud(∼ 220 t km−2 yr−1) denudation and a kinetically limited\udweathering regime of the Southern Sierra Critical Zone Observatory (SSCZO),\udCalifornia, we measured magnesium (Mg) stable isotopes that are sensitive\udindicators of Mg utilisation by biota. We find that Mg is highly\udbio-utilised: 50–100 % of the Mg released by chemical weathering is\udtaken up by forest trees. To estimate the tree uptake of other bio-utilised\udelements (K, Ca, P and Si) we compared the dissolved fluxes of these elements\udand Mg in rivers with their solubilisation fluxes from rock (rock dissolution\udflux minus secondary mineral formation flux). We find a deficit in the\uddissolved fluxes throughout, which we attribute to the nutrient uptake by\udforest trees. Therefore both the Mg isotopes and the flux comparison suggest\udthat a substantial part of the major element weathering flux is consumed by\udthe tree biomass. The enrichment of 26Mg over 24Mg in tree trunks\udrelative to leaves suggests that tree trunks account for a substantial\udfraction of the net uptake of Mg. This isotopic and elemental compartment\udseparation is prevented from obliteration (which would occur by Mg\udredissolution) by two potential effects. Either the mineral nutrients\udaccumulate today in regrowing forest biomass after clear cutting, or they are\udexported in litter and coarse woody debris (CWD) such that they remain in\ud<q>solid</q> biomass. Over pre-forest-management weathering timescales, this\udremoval flux might have been in operation in the form of natural erosion of\udCWD. Regardless of the removal mechanism, our approach provides entirely\udnovel means towards the direct quantification of biogenic uptake following\udweathering. We find that Mg and other nutrients and the plant-beneficial\udelement Si (<q>bio-elements</q>) are taken up by trees at up to 6 m depth, and\udsurface recycling of all bio-elements but P is minimal. Thus, in the\udwatersheds of the SSCZO, the coupling between erosion and weathering might be\udestablished by bio-elements that are taken up by trees, are not recycled and\udare missing in the dissolved river flux due to erosion as CWD and as\udleaf-derived bio-opal for Si. We suggest that the partitioning of a biogenic\udweathering flux into eroded plant debris might represent a significant global\udcontribution to element export after weathering in eroding mountain\udcatchments that are characterised by a continuous supply of fresh mineral\udnutrients

Quantifying nutrient uptake as driver of rock weathering in forest ecosystems by magnesium stable isotopes