Riparian zones possess an unusually diverse array of species and environmental processes. The ecological diversity is related to variable flood regimes, geographically unique channel processes, altitudinal climate shifts, and upland influences on the fluvial corridor. The resulting dynamic environment supports a variety of life-history strategies, biogeochemical cycles and rates, and organisms adapted to disturbance regimes over broad spatial and temporal scales. Innovations in riparian zone management have been effective in ameliorating many ecological issues related to land use and environmental quality. Riparian zones play essential roles in water and landscape planning, in restoration of aquatic systems, and in catalyzing institutional and societal cooperation for these efforts.

The Ecology of Interfaces: Riparian Zones

Many physical, chemical, mineralogical, and biological soil properties can be affected by forest fires. The effects are chiefly a result of burn severity, which consists of peak temperatures and duration of the fire. Climate, vegetation, and topography of the burnt area control the resilience of the soil system; some fire-induced changes can even be permanent. Low to moderate severity fires, such as most of those prescribed in forest management, promote renovation of the dominant vegetation through elimination of undesired species and transient increase of pH and available nutrients. No irreversible ecosystem change occurs, but the enhancement of hydrophobicity can render the soil less able to soak up water and more prone to erosion. Severe fires, such as wildfires, generally have several negative effects on soil. They cause significant removal of organic matter, deterioration of both structure and porosity, considerable loss of nutrients through volatilisation, ash entrapment in smoke columns, leaching and erosion, and marked alteration of both quantity and specific composition of microbial and soil-dwelling invertebrate communities. However, despite common perceptions, if plants succeed in promptly recolonising the burnt area, the pre-fire level of most properties can be recovered and even enhanced. This work is a review of the up-to-date literature dealing with changes imposed by fires on properties of forest soils. Ecological implications of these changes are described.

/pdf/effects-of-fire-on-properties-of-forest-soils-a-review-1ymllzm5e7.pdf

Effects of fire on properties of forest soils: a review

This is a review of worldwide land degradation problems. Four themes are emphasized: delineating and estimating the magnitude of soil erosion, quantifying erosion and sedimentation impacts on land productivity, establishing quantitative values for erosion-causing parameters, and implementing global and regional soil and water conservation programs. Papers deal with both developing and developed countries and illustrate how erosion control techniques used in developed countries can or cannot be applied in developing countries.

https://gendocs.ru/docs/29/28948/conv_1/file1.pdf

Soil Erosion and Conservation

Several recent papers have suggested replacing the terminology of fire intensity and fire severity. Part of the problem with fire intensity is that it is sometimes used incorrectly to describe fire effects, when in fact it is justifiably restricted to measures of energy output. Increasingly, the term has created confusion because some authors have restricted its usage to a single measure of energy output referred to as fireline intensity. This metric is most useful in understanding fire behavior in forests, but is too narrow to fully capture the multitude of ways fire energy affects ecosystems. Fire intensity represents the energy released during various phases of a fire, and different metrics such as reaction intensity, fireline intensity, temperature, heating duration and radiant energy are useful for different purposes. Fire severity, and the related term burn severity, have created considerable confusion because of recent changes in their usage. Some authors have justified this by contending that fire severity is defined broadly as ecosystem impacts from fire and thus is open to individual interpretation. However, empirical studies have defined fire severity operationally as the loss of or change in organic matter aboveground and belowground, although the precise metric varies with management needs. Confusion arises because fire or burn severity is sometimes defined so that it also includes ecosystem responses. Ecosystem responses include soil erosion, vegetation regeneration, restoration of community structure, faunal recolonization, and a plethora of related response variables. Although some ecosystem responses are correlated with measures of fire or burn severity, many important ecosystem processes have either not been demonstrated to be predicted by severity indices or have been shown in some vegetation types to be unrelated to severity. This is a critical issue because fire or burn severity are readily measurable parameters, both on the ground and with remote sensing, yet ecosystem responses are of most interest to resource managers.

/pdf/fire-intensity-fire-severity-and-burn-severity-a-brief-3f34ow4qed.pdf

Fire intensity, fire severity and burn severity: a brief review and suggested usage

https://www.fs.fed.us/rm/pubs_other/rmrs_1999_neary_d001.pdf

Fire effects on belowground sustainability: a review and synthesis

The role of fire and soil heating on water repellency in wildland environments: a review

FIRE DYNAMICS. Combustion Processes and Heat Transfer. Fuels and Fire Behavior. SOIL REPONSES. Soil Resource. Physical Soil System. Chemical Soil System. Biological Soil System. RESPONSES OF OTHER RESOURCES. Water. Vegetation. Wetlands and Riparian Ecosystems. Air. Cultural Resources. MANAGEMENT IMPLICATIONS. Economic Considerations. Fire in Ecosystem Management. Index.

Fire's effects on ecosystems

This state-of-knowledge review about the effects of fire on soils and water can assist land and fire managers with information on the physical, chemical, and biological effects of fire needed to successfully conduct ecosystem management, and effectively inform others about the role and impacts of wildland fire. Chapter topics include the soil resource, soil physical properties and fire, soil chemistry effects, soil biology responses, the hydrologic cycle and water resources, water quality, aquatic biology, fire effects on wetland and riparian systems, fire effects models, and watershed rehabilitation.

https://www.fs.fed.us/rm/pubs/rmrs_gtr042_4.pdf

Wildland fire in ecosystems: effects of fire on soils and water

Water repellency in soils was first described by Schreiner and Shorey (1910), who found that some soils in California could not be wetted and thereby were not suitable for agriculture. Waxy organic substances were responsible for the water repellency. Other studies in the early 1900's on the fairy ring phenomenon suggested that water repellency could be caused by fungi. These fairy rings created unsightly, circular shaped areas in otherwise healthy turf and lawn. Bayliss (1911) reported on such water repellency and referred to earlier work in 1875 by Gilbert and Laws at Rothamsted which described the same phenomenon. Later, Shantz and Piemeisel (1917) confirmed that soil dryness was associated with fairy rings on grasslands in eastern Colorado.

https://www.fs.fed.us/psw/publications/documents/psw_gtr046/psw_gtr046.pdf

Leonard F. DeBano

Papers

Fire effects on belowground sustainability: a review and synthesis

The role of fire and soil heating on water repellency in wildland environments: a review

Fire's effects on ecosystems

Wildland fire in ecosystems: effects of fire on soils and water

Water repellent soils: a state-of-the-art