113 results for group: agrogeology-2


Effects of mineralogy, chemistry and physical properties of basalts on carbon capture potential and plant-nutrient element release via enhanced weathering

Mafic igneous rocks, such as basalt, are composed of abundant calcium- and magnesium-rich silicate minerals widely proposed to be suitable for scalable carbon dioxide removal (CDR) by enhanced rock weathering (ERW). Here, we report a detailed characterization of the mineralogy, chemistry, particle size and surface area of six mined basalts being used in large-scale ERW field trials. We use 1-D reactive transport modelling (RTM) of soil profile processes to simulate inorganic CDR potential via cation flux (Mg2+, Ca2+, K+ and Na+) and assess the release of the essential plant nutrients phosphorus (P) and potassium (K) for a typical clay-loam agricultu...

The usefulness of the rock dust for the remediation of soils contaminated with nickel

The purpose of this research was to examine whether the addi-tion of waste rock dust to light soil contaminated with nickel will increase the yields of cultivated plants and reduce their excessive nickel content. The research was conducted in concrete microplots of 1 m2 dimension in the complete randomisation system, as a two-factor experiment in four replications. The first factor was the level of soil contamination: (1) Ni0 – soil with natural Ni content; (2) Ni1 – 100; (3) Ni2 – 150 and (4) Ni3 – 270 mg • kg-1 of the soil. The second factor was the level of remediation: (1) control without remediation and (2) rock dust at a dose of 3 kg ...

Application of andesite rock as a clean source of fertilizer for eucalyptus crop: Evidence of sustainability

Global demineralization of agricultural soils due to unsustainable use of highly soluble fertilizers and intensive exploitation is an issue of increasing concern. Methods of remineralization include the application of volcanic rock by-product, such as vesicular andesite on mineral-deficient fields. The present work analyzed the petrography, mineralogy, and chemistry of volcanic rock by-product (vesicular andesite rock), as well as on-field experiment with eucalyptus. The petrographic description was performed on a polished thin section by optical microscopy. The mineralogical phases were identified with X-ray diffraction. The by-product chemical ...

Evaluation of Soil Re-mineralizer from By-Product of Volcanic Rock Mining: Experimental Proof Using Black Oats and Maize Crops

This study was focused on physical, petrographical, mineralogical, and chemical characterization of a volcanic-rock mining by-product (dacite rock), as well as on greenhouse experiment with black oats and maize crops to evaluate the potential use of the by-product as soil re-mineralizer. The by-product sample was obtained from a quarry in the Nova Prata mining district in southern Brazil. The particle size distribution of the by-product and soil was determined by sieving. Dacite rock petrographic description was performed on a polished thin section by optical microscopy. The soil and dacite rock mineralogical phases were identified by X-ray diffract...

The potential of rock dust nanoparticles to improve seed germination and seedling vigor of native species: A review

Land degradation as a result of unregulated mineral exploration and mining, negatively impacts local communities and vulnerable ecosystems. Phytoremediation is used as a progressive rehabilitation strategy to stabilize tailings sites, reduce soil erosion and immobilize heavy metal contaminants. However, in order to develop successful and sustainable phytoremediation methods, native plants must overcome several abiotic stressors. This review examines publicly available literature to determine the potential of repurposed tailings materials, in the form of rock dust nanoparticles (RDNPs), as a nanopriming agent to improve seed germination and seedling ...

Rapid Removal of Atmospheric CO2 by Urban Soils

The measured calcium carbonate content of soils to a depth of 100 mm at a large urban development site has increased over 18 months at a rate that corresponds to the sequestration of 85 t of CO2/ha (8.5 kg of CO2 m–2) annually. This is a consequence of rapid weathering of calcium silicate and hydroxide minerals derived from the demolition of concrete structures, which releases Ca that combines with CO2 ultimately derived from the atmosphere, precipitating as calcite. Stable isotope data confirm an atmospheric origin for carbonate carbon, and 14C dating indicates the predominance of modern carbon in the pedogenic calcite. Trial pits show that ...

Soil remineralization and recovery of degraded areas: An experience in the tropical region

Many activities related to the expansion of food supply, energy and infrastructure result in great environmental impacts, whose most visible features are observed in the degradation of large areas. The present study demonstrates how the combined use of stonemeal technology and agroforestry systems can help to reverse such impacts, allying the recovery of degraded areas with agricultural and forest production. The study area is located in a hydroelectric reservoir affected by the siltation process and soil erosion in the hydrographic basin of the San Francisco River, Brazil. An Experimental Unit (EU) was set up in the Ecological Station of Pirapitinga ...

Co-utilization of rock dust, mineral fines and compost

This report examines the relevance and potential of techniques using rockdust to remineralize soils in Scotland. Rockdust (RD) is a generic term applied to fine materials produced as by-products of quarrying and mineral processing. The concept is concerned with making available a multitude of minerals from freshly crushed rocks that are considered by advocates not to be present in larger quantities in weathered soils. Claimed benefits include : •enhanced long term sustainable soil fertility and diverse soil biology; •multi-season effects; •enhanced plant establishment, growth and vigour; •compatibility with organic farming practices; ...

Calcium-mediated stabilisation of soil organic carbon

Soils play an essential role in the global cycling of carbon and understanding the stabilisation mechanisms behind the preservation of soil organic carbon (SOC) pools is of globally recognised significance. Until recently, research into SOC stabilisation has predominantly focused on acidic soil environments and the interactions between SOC and aluminium (Al) or iron (Fe). The interactions between SOC and calcium (Ca) have typically received less attention, with fewer studies conducted in alkaline soils. Although it has widely been established that exchangeable Ca (CaExch) positively correlates with SOC concentration and its resistance to oxidation, ...

Silicon-augmented resistance of plants to herbivorous insects: a review

Silicon (Si) is one of the most abundant elements in the earth's crust, although its essentiality in plant growth is not clearly established. However, the importance of Si as an element that is particularly beneficial for plants under a range of abiotic and biotic stresses is now beyond doubt. This paper reviews progress in exploring the benefits at two- and three-trophic levels and the underlying mechanism of Si in enhancing the resistance of host plants to herbivorous insects. Numerous studies have shown an enhanced resistance of plants to insect herbivores including folivores, borers, and phloem and xylem feeders. Silicon may act directly on insect ...