Comment on [open quotes]Weathering, plants, and the long-term carbon cycle[close quotes] by Robert A. Berner

Journal Article · Sat May 01 00:00:00 EDT 1993 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(93)90099-I· OSTI ID:6182518

Jackson, T A ^[1]

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1. National Water Research Inst., Burlington, Ontario (Canada)

Berner (1992) has asserted that Jackson and Keller (1970a) misinterpreted the conspicuous reddish crust which forms on young lava flows in areas of rock surface colonised by the lichen Stereocaulon vulcani (but not in adjacent areas of bare rock) in regions of high rain fall on the Island of Hawaii. Jackson (1968) and Jackson and Keller (1970a,b) concluded from the results of a thorough interdisiplinary investigation employing a wide spectrum of techniques and information that his reddish coating, is an intensely leached weathering crust formed in situ, and that biochemical activities of the lichen or its associated microflora not only accelerate the chemical weathering of the rock by orders of magnitude but also determine the specific mineralogical and chemical properties of the weathering products. Berner, however, maintained that the reddish crust is in reality a deposit of [open quotes]wind-blown soil dust[close quotes] entrapped by a sticky organic substance secreted by the lichen. Berner fixed his attention on just one aspect of the many-sided body of interrelated data on which the conclusions of Jackson and Keller are founded-the observation that the weathering crust is much thicker on lichen-covered rock surfaces than on lichen-free [open quotes]control[close quotes] areas of the same rock. The totality of published evidence overwhelmingly supports the conclusions of Jackson and Keller an demonstrates that Berner's rival hypothesis is untenable.

• OSTI ID: 6182518
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Vol. 57:9; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
LAVA
WEATHERING
LICHENS
BIODEGRADATION
ATMOSPHERIC PRECIPITATIONS
CARBON CYCLE
IRON OXIDES
ALGAE
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
EUMYCOTA
FUNGI
IRON COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PLANTS
TRANSITION ELEMENT COMPOUNDS
540210* - Environment
Terrestrial- Basic Studies- (1990-)
540110