165 results for group: journal-article

Direct measurement of CO2 drawdown in mine wastes and rock powders: Implications for enhanced rock weathering

Amanda R.Stubbs, Carlos Paulo, Ian M.Power, Baolin Wang, Nina Zeyen, Siobhan A.Wilson Abstract Enhanced rock weathering (ERW) sequesters CO2 via solubility and mineral trapping and can be implemented by the mining industry to reduce their net greenhouse gas emissions. Kimberlite residues from Venetia Diamond Mine in South Africa, as well as powdered forsterite, serpentinite, wollastonite skarn, and 10 wt.% brucite mixed with quartz sand, were tested as potential feedstocks for ERW. A CO2 flux system directly measured CO2 removal rates and sensors tracked laboratory conditions and pore water saturation during a series of 2-week experiments. With ...

Bedrock Weathering Controls on Terrestrial Carbon-Nitrogen-Climate Interactions

Pawlok Dass, Benjamin Z. Houlton, Yingping Wang, David Wårlind, Scott Morford Abstract Anthropogenic nitrogen deposition is widely considered to increase CO2 sequestration by land plants on a global scale. Here, we demonstrate that bedrock nitrogen weathering contributes significantly more to nitrogen-carbon interactions than anthropogenic nitrogen deposition. This working hypothesis is based on the introduction of empirical results into a global biogeochemical simulation model over the time period of the mid-1800s to the end of the 21st century. Our findings suggest that rock nitrogen inputs have contributed roughly 2–11 times more to plant ...

Global Beiogeochemical Cycles

Anthropogenic nitrogen deposition is widely considered to increase CO2 sequestration by land plants on a global scale. Here, we demonstrate that bedrock nitrogen weathering contributes significantly more to nitrogen-carbon interactions than anthropogenic nitrogen deposition. This working hypothesis is based on the introduction of empirical results into a global biogeochemical simulation model over the time period of the mid-1800s to the end of the 21st century. Our findings suggest that rock nitrogen inputs have contributed roughly 2–11 times more to plant CO2 capture than nitrogen deposition inputs since pre-industrial times. Climate change ...

Remineralizing soils? The agricultural usage of silicate rock powders: A review

Philipp Swoboda Thomas F.Döring Martin Hamer Abstract Soil nutrient depletion threatens global food security and has been seriously underestimated for potassium (K) and several micronutrients. This is particularly the case for highly weathered soils in tropical countries, where classical soluble fertilizers are often not affordable or not accessible. One way to replenish macro- and micronutrients are ground silicate rock powders (SRPs). Rock forming silicate minerals contain most nutrients essential for higher plants, yet slow and inconsistent weathering rates have restricted their use in the past. Recent findings, however, challenge past ...

Testing the ability of plants to access potassium from framework silicate minerals

David A C Manning, Joana Baptista, Mallely Sanchez Limon, Kirsten Brandt Abstract The availability of K, essential for plant growth, from syenite (a silicate rock in which potassium feldspar is the dominant mineral; N 90 wt%), and phlogopite mica has been demonstrated using carefully designed plant growth pot experiments in which the only added source of K was the mineral of interest, with no loss of nutrients through drainage. Using pure quartz sand as a soil, both growth (increase in diameter) of leek plants and K-content of the plant material showed a dose-dependent positive response to the application (114–43000 mg K/pot) of milled ...

Enhanced weathering strategies for stabilizing climate and averting ocean acidification

Lyla L. Taylor, Joe Quirk, Rachel M. S. Thorley, Pushker A. Kharecha, James Hansen, Andy Ridgwell, Mark R. Lomas, Steve A. Banwart & David J. Beerling Abstract Chemical breakdown of rocks, weathering, is an important but very slow part of the carbon cycle that ultimately leads to CO2 being locked up in carbonates on the ocean floor. Artificial acceleration of this carbon sink via distribution of pulverized silicate rocks across terrestrial landscapes may help offset anthropogenic CO2 emissions . We show that idealized enhanced weathering scenarios over less than a third of tropical land could cause significant drawdown of atmospheric CO2 ...

On life-cycle sustainability optimization of enhanced weathering systems

Raymond R.Tan, Kathleen B.Aviso Abstract Enhanced weathering is a simple and scalable negative emissions technology with an estimated carbon dioxide removal potential of multiple gigatons per year. To date, the only life-cycle assessment of enhanced weathering was published by Lefebvre et al. (2019) in this journal. They estimated the carbon dioxide removal potential in Sao Paolo State in Brazil to be 1.3e2.4 Mt/y, examined the penalty from transportation greenhouse gas emissions, and pointed out that using life-cycle assessment can give more reliable estimates of climate change mitigation potential of enhanced weathering systems. In this ...

Solutions for a cultivated planet

Jonathan A. Foley, Navin Ramankutty, Kate A. Brauman, Emily S. Cassidy, James S. Gerber, Matt Johnston, Nathaniel D. Mueller, Christine O’Connell, Deepak K. Ray, Paul C. West, Christian Balzer, Elena M. Bennett, Stephen R. Carpenter, Jason Hill, Chad Monfreda, Stephen Polasky, Johan Rockström, John Sheehan, Stefan Siebert, David Tilman & David P. M. Zaks Abstract Increasing population and consumption are placing unprecedented demands on agriculture and natural resources. Today, approximately a billion people are chronically malnourished while our agricultural systems are concurrently degrading land, water, biodiversity and climate on ...

Investigating carbonate formation in urban soils as a method for capture and storage of atmospheric carbon

C.-L.Washbourne, P.Renforth, D.A.C.Manninga Abstract This paper investigates the potential for engineered urban soils to capture and store atmospheric carbon (C). Calcium (Ca) and magnesium (Mg) bearing waste silicate minerals within the soil environment can capture and store atmospheric C through the process of weathering and secondary carbonate mineral precipitation. Anthropogenic soils, known to contain substantial quantities of Ca and Mg-rich minerals derived from demolition activity (particularly cement and concrete), were systematically sampled at the surface across a 10 ha brownfield site, Science Central, located in the urban ...

Persistence of soil organic matter as an ecosystem property

Michael W. I. Schmidt, Margaret S. Torn, Samuel Abiven, Thorsten Dittmar, Georg Guggenberger, Ivan A. Janssens, Markus Kleber, Ingrid Kögel-Knabner, Johannes Lehmann, David A. C. Manning, Paolo Nannipieri, Daniel P. Rasse, Steve Weiner & Susan E. Trumbore Abstract Globally, soil organic matter (SOM) contains more than three times as much carbon as either the atmosphere or terrestrial vegetation. Yet it remains largely unknown why some SOM persists for millennia whereas other SOM decomposes readily—and this limits our ability to predict how soils will respond to climate change. Recent analytical and experimental advances have demons...