165 results for group: journal-article

The potential for carbon dioxide removal by enhanced rock weathering in the tropics: An evaluation of Costa Rica

Abstract Tropical environments show great potential to sequester CO2 by enhanced rock weathering (ERW) of powdered mafic rocks applied to agricultural fields. This study seeks to assess carbon dioxide reduction (CDR) potential in the humid tropics (1) by experimental weathering of mafic rock powders in conditions simulating humid tropical soils, and (2) from weathering rates determined from a Holocene tropical soil chronosequence where parent material is andesitic sediments. Experimentally determined weathering rates by leaching of basaltic andesites from Costa Rica (Arenal and Barva) for 50 t ha−1 applications indicate potential sequestration ...

The impact of geochemical and life-cycle variables on carbon dioxide removal by enhanced rock weathering: Development and application of the Stella ERW model

ABSTRACT The carbon dioxide removal (CDR) potential of enhanced rock weathering (ERW) depends on dynamic interactions between several biogeochemical and life-cycle variables. This paper reports results from a systems model developed to account for key variable interactions and provide a computational tool for optimizing ERW applications. We discuss the model development, comparisons with laboratory and field test data, and results from a series of sensitivity analyses for several hypothetical ERW applications. The simulations were performed using a model developed in Stella Architect, an object-oriented systems dynamics modeling code. The model ...

Initial agronomic benefits of enhanced weathering using basalt: A study of spring oat in a temperate climate

ABSTRACT Addressing soil nutrient degradation and global warming requires novel solutions. Enhanced weathering using crushed basalt rock is a promising dual-action strategy that can enhance soil health and sequester carbon dioxide. This study examines the short-term effects of basalt amendment on spring oat (Avena sativa L.) during the 2022 growing season in NE England. The experimental design consisted of four blocks with control and basalt- amended plots, and two cultivation types within each treatment, laid out in a split plot design. Basalt (18.86 tonnes ha−1) was incorporated into the soil during seeding. Tissue, grain and soil samples ...

Organic carbon source controlled microbial olivine dissolution in small-scale flow-through bioreactors, for CO2 removal

ABSTRACT The development of carbon dioxide removal methods, coupled with decreased CO2 emissions, is fundamental to achieving the targets outlined in the Paris Agreement limiting global warming to 1.5 °C. Here we are investigating the importance of the organic carbon feedstock to support silicate mineral weathering in small-scale flow through bioreactors and subsequent CO2 sequestration. Here, we combine two bacteria and two fungi, widely reported for their weathering potential, in simple flow through bioreactors (columns) consisting of forsterite and widely available, cheap organic carbon sources (wheat straw, bio-waste digestate of pig ...

Soil cation storage as a key control on the timescales of carbon dioxide removal through enhanced weathering

ABSTRACT Significant interest and capital are currently being channeled into techniques for durable carbon dioxide removal (CDR) from Earth’s atmosphere. A particular class of these approaches (referred to as enhanced weathering (EW)) seeks to modify the surface alkalinity budget to durably store CO2 as dissolved inorganic carbon species. Here, we use SCEPTER (a reaction- transport code designed to simulate EW in managed lands) to evaluate the throughput and storage timescales of anthropogenic alkalinity in agricultural soils. Through a series of alkalinity flux simulations, we explore the main controls on cation storage and export from ...

India’s biogeochemical capacity to attain food security and remediate climate

Ishfaq Ahmad Mir, Thomas J F Goreau, Joanna Campe, James Jerden Abstract In order to supply wholesome food and slow down climate change, this paper covers India's agrogeological resources. The soils are the result of the weathering of rocks with ages ranging from more than a billion years to the most recent Holocene. Because they are severely deficient in vital minerals, many soils have low agricultural production. In addition to helping to fertilise soils, reduce atmospheric carbon dioxide levels, and stop the acidification of the Indian Ocean, rock powder weathering and biochar have significant positive effects on the productivity of Indian ...

Environmental impacts and resource use of urban agriculture: a systematic review and meta-analysis

Erica Dorr, Benjamin Goldstein, Arpad Horvath, Christine Aubry, and Benoit Gabrielle Abstract Environmental merits are a common motivation for many urban agriculture (UA) projects. One powerful way of quantifying environmental impacts is with life cycle assessment (LCA): a method that estimates the environmental impacts of producing, using, and disposing of a good. LCAs of UA have proliferated in recent years, evaluating a diverse range of UA systems and generating mixed conclusions about their environmental performance. To clarify the varied literature, we performed a systematic review of LCAs of UA to answer the following questions: What is ...

Impact of Climate on the Global Capacity for Enhanced Rock Weathering on Croplands

Seung H. Baek, Yoshiki Kanzaki, Juan M. Lora, Noah Planavsky, Christopher T. Reinhard, Shuang Zhang Abstract Enhanced rock weathering (ERW) on croplands has emerged as an economically and ecologically promising negative emissions technology. However, estimated total carbon sequestration potential from ERW on croplands and its potential sensitivity to climate conditions requires further understanding. Here we combine 1-D reactive transport modeling with climate model experiments to simulate ERW on ∼1,000 agricultural sites globally. Applying a fixed rate of 10 tons of basalt dust per hectare on these sites sequesters 64 gigatons of CO2 over a ...

Improved net carbon budgets in the US Midwest through direct measured impacts of enhanced weathering

Ilsa B. Kantola, Elena Blanc-Betes, Michael D. Masters, Elliot Chang, Alison Marklein, Caitlin E. Moore, Adam von Haden, Carl J. Bernacchi, Adam Wolf, Dimitar Z. Epihov, David J. Beerling, Evan H. DeLucia Abstract Terrestrial enhanced weathering (EW) through the application of Mg- or Ca- rich rock dust to soil is a negative emission technology with the potential to address impacts of climate change. The effectiveness of EW was tested over 4 years by spreading ground basalt (50 t ha−1 year−1) on maize/soybean and miscanthus cropping systems in the Midwest US. The major elements of the carbon budget were quantified through ...

Enhanced clay formation key in sustaining the Middle Eocene Climatic Optimum

Alexander J. Krause, Appy Sluijs, Robin van der Ploeg, Timothy M. Lenton & Philip A. E. Pogge von Strandmann Abstract The Middle Eocene Climatic Optimum (around 40 million years ago) was a roughly 400,000-year-long global warming phase associated with an increase in atmospheric CO2 concentrations and deep-ocean acidification that interrupted the Eocene’s long-term cooling trend. The unusually long duration, compared with early Eocene global warming phases, is puzzling as temperature-dependent silicate weathering should have provided a negative feedback, drawing down CO2 over this timescale. Here we investigate silicate weathering during this ...