Energy & Green Tech

Wireless tech measures soil moisture at multiple depths in real time

Researchers from North Carolina State University have developed a wireless system that uses radio transmitters and receivers to estimate soil moisture in agricultural fields at multiple depths in real time, improving on existing ...

Engineering

Building the future with self-healing concrete and biocement

After water, concrete is the most widely used substance on Earth. With applications from housing and industry to coastal defense and infrastructure, concrete and cement are at the cornerstone of life, quite literally.

Engineering

Bridges under pressure

Can a bridge withstand an earthquake? One of the big unknowns is how far a bridge might settle from seismic shaking, especially if the shaking triggers a quicksand-like soil response called liquefaction.

Engineering

Permeable pavements to help mitigate flood disasters

This year has seen one of Australia's worst flood disasters on record in the eastern states, with 23 people killed, thousands left homeless, and a damage bill expected to top $1.5 billion.

Business

Cyber attacks could jeopardize global food supplies

Wide-ranging use of smart technologies is raising global agricultural production but international researchers warn this digital-age phenomenon could reap a crop of another kind—cybersecurity attacks.

Electronics & Semiconductors

Computer scientists show how bacteria can fuel low-power sensors

Computer scientists at the University of California San Diego are showing how soil microbes can be harnessed to fuel low-power sensors. This opens new possibilities for microbial fuel cells (MFCs), which can power soil hydration ...

Energy & Green Tech

Bees, sheep, crops: Solar developers tout multiple benefits

Silflower was among native plants that blanketed the vast North American prairie until settlers developed farms and cities. Nowadays confined largely to roadsides and ditches, the long-stemmed cousin of the sunflower may ...

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Soil

Soil is a natural body consisting of layers (soil horizons) of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics. It is composed of particles of broken rock that have been altered by chemical and environmental processes that include weathering and erosion. Soil differs from its parent rock due to interactions between the lithosphere, hydrosphere, atmosphere, and the biosphere. It is a mixture of mineral and organic constituents that are in solid, gaseous and aqueous states. Soil particles pack loosely, forming a soil structure filled with pore spaces. These pores contain sol solution (liquid) and air (gas). Accordingly, soils are often treated as a three state system. Most soils have a density between 1 and 2 g/cm³. Soil is also known as earth: it is the substance from which our planet takes its name. Little of the soil composition of planet Earth is older than Tertiary and most no older than Pleistocene. In engineering, soil is referred to as regolith, or loose rock material.

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