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Water is one of the agents of deterioration. Its effects can be seen in these flood-damaged library books. The 'ten agents of deterioration' are a conceptual framework developed by the Canadian Conservation Institute (CCI) used to categorise the major causes of change, loss or damage to cultural heritage objects (such as collections held by galleries, libraries, archives and museums). [1]
Environmental degradation is the deterioration of the environment through depletion of resources such as quality of air, water and soil; the destruction of ecosystems; habitat destruction; the extinction of wildlife; and pollution. It is defined as any change or disturbance to the environment perceived to be deleterious or undesirable.
Various types of aggregates can undergo different chemical reactions and swell inside concrete, leading to damaging expansive phenomena. Alkali–silica reaction. The most common are those containing reactive amorphous silica, that can react in the presence of water with the cement alkalis (K 2 O and Na 2 O).
In addition to the usual types of land degradation that have been known for centuries (water, wind and mechanical erosion, physical, chemical and biological degradation), four other types have emerged in the last 50 years: [11] pollution, often chemical, due to agricultural, industrial, mining or commercial activities;
Degradation is an evolution, different from natural evolution, related to the local climate and vegetation. [1] It is due to the replacement of primary plant communities (known as climax vegetation) by the secondary communities. This replacement modifies the humus composition and amount, and affects the formation of the soil. It is directly ...
Infrared light heats the surface of objects, which is a form of incorrect temperature. Different deterioration phenomena often occur simultaneously. [7] Inappropriate temperature is another source of deterioration. There are several ways that temperature can cause object degradation. One being that the temperature is too high: this excess heat ...
Polymer degradation is the reduction in the physical properties of a polymer, such as strength, caused by changes in its chemical composition.Polymers and particularly plastics are subject to degradation at all stages of their product life cycle, including during their initial processing, use, disposal into the environment and recycling. [1]
Dobbingstone Burn, Scotland—This photo illustrates two different types of erosion affecting the same place. Valley erosion is occurring due to the flow of the stream, and the boulders and stones (and much of the soil) that are lying on the edges are glacial till that was left behind as ice age glaciers flowed over the terrain.