Featured Image: Small headwater stream in Oregon’s Mountains. Image courtesy Jessica Buser-Young, used with permission.
Paper: The River Continuum Concept
Authors: Robin L. Vannote, G. Wayne Minshall, Kenneth W. Cummins, James R. Sedell, Colbert E. Cushing
Perhaps last time you went for a hike, you stumbled upon a burbling spring pushing its way up through the leaf litter after a heavy rainfall, creating a tiny rivulet of water crisscrossing over your path before plunging back into the forest. What a find! Excitedly, you squatted down and gently uncovered the spring to notice gnats lazily floating away, some nearby fruiting mushrooms, and great clumps of decomposing twigs and leaves which you assume harbor uncountable numbers of microorganisms. This unique little ecosystem is profiting from the nutrients and water being pushed from the ground, using the opportunity to have a feast. But what happens to the nutrients and carbon that gets past these plants and animals?
Continue reading “Mosaics of Life Along a River”
Featured Image: Iceberg in North Star Bay, Greenland by Jeremy Harbeck – NASA, Public Domain
Paper: Subsurface In Situ Detection of Microbes and Diverse
Organic Matter Hotspots in the Greenland Ice Sheet
Authors: Michael J. Malaska, Rohit Bhartia, Kenneth S. Manatt, John C. Priscu, William J. Abbey, Boleslaw Mellerowicz, Joseph Palmowski, Gale L. Paulsen, Kris Zacny, Evan J. Eshelman, and Juliana D’Andrilli
Like the rings of a tree, core samples extracted from glacial ice preserve a unique record of past events. But instead of recording seasonal growth, the ancient ice sheets of Antarctica and Greenland have preserved the conditions of long gone climates and ecosystems. Some sheets have continuously accumulated so much snowfall over the past series of millennia that in some places the ice can reach depths that are miles deep. Analyzing this immense glacial record can inform us about not just the global patterns of climate change, but also the evolution of microbial life on Earth, and maybe even the icy worlds of our Solar System.
Continue reading “New instrument maps and preserves frozen habitats on Earth- and potentially icy worlds”
Featured Image used with permission of photographer (Cassi Wattenburger)
Paper: Indigenous microbes induced fluoride release from aquifer sediments
Authors: Xubo Gao, Wenting Luo, Xuesong Luo, Chengcheng Li, Xin Zhang, Yanxin Wang
My science textbook taught me that fluorine (F) was really important for dental health, and I’ve since learned that both excessive and insufficient amounts of fluoride in groundwater can cause health issues. While the chemistry behind the release of fluoride ions from rocks or sediments into groundwater is well understood, the microbiology of this process is not. Specifically, scientists have been wondering whether microbes could speed up the release of F from sediments into groundwater.
Continue reading “Do Microbes Release Fluorine from Rocks?”
Featured image: Cambrian stromatolites from New York State. Image attribution: James St. John / CC BY 2.0; Wikimedia Commons
Paper: Evidence for microbes in early Neoproterozoic stromatolites
Authors: Zhongwu Lan, Shujing Zhang, Maurice Tucker, Zhensheng Li, Zhuoya Zhao
Stromatolites are ancient, layered deposits of sediments that are characterized by thin, alternating light and dark bands. While microbial fossils have been found in many stromatolites, the biological origin of these structures has been debated. Continue reading “Ancient microbes engineered sedimentary deposits”