Lecture

Organic matter reactivity: Pools, Ageing, and Transformations

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Description

This lecture covers the reactivity of organic matter in water systems, including the pools and ageing of organic matter, the transformation and roles of different organic compounds, and the physico-chemical properties affecting their behavior. It discusses the distinction between allochthonous and autochthonous organic matter, their degradation processes, and their impact on water biogeochemistry. The lecture also explores the operational definitions of different organic compounds, the hydrophobicity versus hydrophilicity of organic matter, and the complexation sites on organic matter. Additionally, it delves into the significance of organic matter in slow nutrient release, soil structure, and chelation of cations, emphasizing the importance of understanding the different pools of soil organic matter and their recalcitrance to biodegradation.

Official source

Ontological neighbourhood

Biology

Ecology: Ecosystems

Related concepts (32)

Soil structure

In geotechnical engineering, soil structure describes the arrangement of the solid parts of the soil and of the pore space located between them. It is determined by how individual soil granules clump, bind together, and aggregate, resulting in the arrangement of soil pores between them. Soil has a major influence on water and air movement, biological activity, root growth and seedling emergence. There are several different types of soil structure. It is inherently a dynamic and complex system that is affected by different factors.

Organic matter

Organic matter, organic material, or natural organic matter refers to the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have come from the feces and remains of organisms such as plants and animals. Organic molecules can also be made by chemical reactions that do not involve life. Basic structures are created from cellulose, tannin, cutin, and lignin, along with other various proteins, lipids, and carbohydrates.

Soil biology

Soil biology is the study of microbial and faunal activity and ecology in soil. Soil life, soil biota, soil fauna, or edaphon is a collective term that encompasses all organisms that spend a significant portion of their life cycle within a soil profile, or at the soil-litter interface. These organisms include earthworms, nematodes, protozoa, fungi, bacteria, different arthropods, as well as some reptiles (such as snakes), and species of burrowing mammals like gophers, moles and prairie dogs.

Soil

Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life of plants and soil organisms. Some scientific definitions distinguish dirt from soil by restricting the former term specifically to displaced soil. Soil consists of a solid phase of minerals and organic matter (the soil matrix), as well as a porous phase that holds gases (the soil atmosphere) and water (the soil solution). Accordingly, soil is a three-state system of solids, liquids, and gases.

Soil organic matter

Soil organic matter (SOM) is the organic matter component of soil, consisting of plant and animal detritus at various stages of decomposition, cells and tissues of soil microbes, and substances that soil microbes synthesize. SOM provides numerous benefits to the physical and chemical properties of soil and its capacity to provide regulatory ecosystem services. SOM is especially critical for soil functions and quality.

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