Biogeochemical weathering of soil apatite grains in the McMurdo Dry Valleys, Antarctica

Heindel, Ruth C.; Lyons, W. Berry; Welch, Susan A.; Spickard, Angela M.; Virginia, Ross A.

doi:10.1016/j.geoderma.2018.01.027

Cited by 20 publications

(15 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This discussion section links results presented in Figures 1-13 to prior scholarship on cold climate rock-surface processes. The results clearly confirm findings by Rapp [23], Hall [14,[24][25][26], Dixon [27][28][29][30][31][32][33][34][35], Thorn [36][37][38], their collaborators, and others [40][41][42][43][44][45][46][47][105][106][107] on the importance of chemical processes in cold climate geomorphic settings. However, Figures 1-13 also reveal new details of rock-surface chemical l processes at the nanoscale that, we hope, opens the eyes of cold-climate researchers who only perceive "minimal chemical weathering" [39] when they see bare rock (e.g., Figures 1, 11 and 13a).…”

Section: Discussionsupporting

confidence: 84%

“…Unfortunately, there still exists the assumption by some of "minimal chemical weathering" in cold climates like Antarctica [39]. However, most scholars no longer consider biochemical and chemical rock decay processes as unimportant or even a distant second to physical rock decay, as evidenced by recent research [40][41][42][43][44][45][46][47] and Ph.D. dissertations [48] on cold-climate rock decay not having fight against those prejudiced by the old paradigm.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Nanoscale Observations Support the Importance of Chemical Processes in Rock Decay and Rock Coating Development in Cold Climates

Dorn

Krinsley

2019

Geosciences

View full text Add to dashboard Cite

Conventional scholarship long held that rock fracturing from physical processes dominates over chemical rock decay processes in cold climates. The paradigm of the supremacy of cold-climate shattering was questioned by Rapp’s discovery (1960) that the flux of dissolved solids leaving a Kärkevagge, Swedish Lapland, watershed exceeded physical denudation processes. Many others since have gone on to document the importance of chemical rock decay in all cold climate landscapes, using a wide variety of analytical approaches. This burgeoning scholarship, however, has only generated a few nanoscale studies. Thus, this paper’s purpose rests in an exploration of the potential for nanoscale research to better understand chemical processes operating on rock surfaces in cold climates. Samples from several Antarctica locations, Greenland, the Tibetan Plateau, and high altitude tropical and mid-latitude mountains all illustrate ubiquitous evidence of chemical decay at the nanoscale, even though the surficial appearance of each landscape is dominated by “bare fresh rock.” With the growing abundance of focused ion beam (FIB) instruments facilitating sample preparation, the hope is that that future rock decay researchers studying cold climates will add nanoscale microscopy to their bag of tools.

show abstract

Section: Discussionsupporting

confidence: 84%

Section: Introductionmentioning

confidence: 99%

Nanoscale Observations Support the Importance of Chemical Processes in Rock Decay and Rock Coating Development in Cold Climates

Dorn

Krinsley

2019

Geosciences

View full text Add to dashboard Cite

show abstract

“…VG narrows downstream and drains into Lake Fryxell near the "gage" transect, while RC merges with Harnish Creek before reaching its outlet. Both streams are likely N-limited given their low nitrate concentrations (McKnight et al 2004(McKnight et al , 2007 and the continuous supply of phosphorus (P) from apatite weathering (Heindel et al 2018).…”

Section: Site Descriptionmentioning

confidence: 99%

Catch and release: Hyporheic retention and mineralization of N‐fixing Nostoc sustains downstream microbial mat biomass in two polar desert streams

Kohler

Stanish

Liptzin

et al. 2018

Limnol Oceanogr Letters

View full text Add to dashboard Cite

Much work has been performed to investigate controls on nitrogen (N) uptake in streams, yet the fate of assimilated N is comparatively poorly resolved. Here, we use in-stream fixed N as an isotopic tracer to study the fate of assimilated N in glacial meltwater streams. We characterized d 15 N signatures of Oscillatorean, Chlorophyte, and N-fixing Nostoc mats over the lengths of two streams, and transported particulate organic matter (POM) in one. POM was isotopically most similar to Nostoc, which always had values near the atmospheric standard (d 15 N ffi 0&), suggesting N-fixation. Other mat types were depleted upstream, and became progressively enriched downstream (plateauing at d 15 N ffi 0&), indicating a shift in N source. These results collectively show that Nostoc-derived N is mobilized, mineralized, and increasingly assimilated downstream as more depleted glacier-derived N is exhausted, demonstrating the importance of organic matter processing to balancing elemental budgets, and improving our understanding of nutrient cycling in lotic environments. Additional Supporting Information may be found in the online version of this article.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Scientific Significance StatementNitrogen (N) pollution is a widespread environmental problem, and considerable effort over the last few decades has been invested in understanding how stream systems store, transform, and export N. However, most of this work has focused on microbial uptake and incorporation of N, rather than what happens to the N downstream. In this study, we traced N originating from N-fixing cyanobacteria through Antarctic glacial meltwater streams to demonstrate that N incorporated into microbial mats is repeatedly recycled and exported downstream, maintaining mat communities as other sources of N are exhausted. Our results demonstrate the potential importance of N-fixation and organic matter cycling in supporting primary production in N-limited streams.

show abstract

“…Apatite is a primary source of P in terrestrial ecosystems and occurs as a lithogenic mineral in soils worldwide. The release of P from the lithosphere into the soil is affected by many physical, chemical, and biological processes [8], where weathering and dissolution of apatite will release secondary precipitated P, differing in stability [9]. The use of solid hydroxyapatites (HA) as direct P source is ineffective, because the large size of the particles, in addition to a high soil pH, limits P mobility and hence, bioavailability to plants.…”

Section: Introductionmentioning

confidence: 99%

Kinetics of Phosphorus Release from Vivianite, Hydroxyapatite, and Bone Char Influenced by Organic and Inorganic Compounds

2020

View full text Add to dashboard Cite

The availability of P is often insufficient and limited by accumulation in soils. This led to the necessity of solutions for the recovery as well as recycling of secondary P resources. Batch experiments were conducted with CaCl2 and citric acid to characterize P release kinetics from vivianite, hydroxyapatite, and bone char. While the P release during the CaCl2 treatment was so low that only vivianite and hydroxyapatite showed a slightly higher release with increasing CaCl2 concentration, the increase of dissolved P was more pronounced for citric acid. The application of citric acid resulted in a 32,190-fold higher P release for bone char. Fourier-transform infrared spectroscopic data suggested higher instability of hydroxyapatite than for bone char. The kinetic data showed that bone char, especially at a lower particle size, had a higher long-term P release than hydroxyapatite or vivianite. The suitability of hydroxyapatite and bone char as a poorly soluble, but sustainable P source is better than that of vivianite. However, the efficiency as a P fertilizer is also dependent on present soil P mobilization processes. The results underline the importance of the accessibility of fertilized or naturally bound P for plant roots to benefit from the excretion of organic acids.

show abstract

Biogeochemical weathering of soil apatite grains in the McMurdo Dry Valleys, Antarctica

Cited by 20 publications

References 38 publications

Nanoscale Observations Support the Importance of Chemical Processes in Rock Decay and Rock Coating Development in Cold Climates

Nanoscale Observations Support the Importance of Chemical Processes in Rock Decay and Rock Coating Development in Cold Climates

Catch and release: Hyporheic retention and mineralization of N‐fixing Nostoc sustains downstream microbial mat biomass in two polar desert streams

Kinetics of Phosphorus Release from Vivianite, Hydroxyapatite, and Bone Char Influenced by Organic and Inorganic Compounds

Contact Info

Product

Resources

About