Microbial origin of desert varnish.
نویسندگان
چکیده
Scanning electron microscopy and energy dispersive x-ray analyses of desert varnish reveal that microorganisms concentrate ambient manganese that becomes greatly enhanced in brown to black varnish. Specific characteristics of desert varnish and of varnish bacteria support a microbial origin for manganese-rich films. Varnish microbes can be cultured and produce laboratory manganese films. Accordingly, natural desert varnish and also manganese-rich rock varnishes in nondesert environments appear to be a product of microbial activity.
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ورودعنوان ژورنال:
- Science
دوره 213 4513 شماره
صفحات -
تاریخ انتشار 1981