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Ant diversity in Brazilian tropical dry forests across multiple vegetation domains 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2017, 12 (3)
作者:  Silva, Luciana Figueiredo;  Souza, Rayana Mello;  Solar, Ricardo R. C.;  Neves, Frederico de Siqueira
收藏  |  浏览/下载：8/0  |  提交时间：2019/04/09
alpha diversity  beta diversity  historical mechanisms  regional scale  species turnover  transitional zones  
Radiochemically-Supported Microbial Communities: A Potential Mechanism for Biocolloid Production of Importance to Actinide Transport 科技报告
来源：US Department of Energy (DOE). 出版年： 2014
作者:  Moser, Duane P;  Hamilton-Brehm, Scott D;  Fisher, Jenny C;  Bruckner, James C;  Kruger, Brittany;  Sackett, Joshua;  Russell, Charles E;  Onstott, Tullis C;  Czerwinski, Ken
收藏  |  浏览/下载：42/0  |  提交时间：2019/04/05
Due to the legacy of Cold War nuclear weapons testing  the Nevada National Security Site (NNSS  formerly known as the Nevada Test Site (NTS)) contains millions of Curies of radioactive contamination. Presented here is a summary of the results of the first comprehensive study of subsurface microbial communities of radioactive and nonradioactive aquifers at this site. To achieve the objectives of this project  cooperative actions between the Desert Research Institute (DRI)  the Nevada Field Office of the National Nuclear Security Administration (NNSA)  the Underground Test Area Activity (UGTA)  and contractors such as Navarro-Interra (NI)  were required. Ultimately  fluids from 17 boreholes and two water-filled tunnels were sampled (sometimes on multiple occasions and from multiple depths) from the NNSS  the adjacent Nevada Test and Training Range (NTTR)  and a reference hole in the Amargosa Valley near Death Valley. The sites sampled ranged from highly-radioactive nuclear device test cavities to uncontaminated perched and regional aquifers. Specific areas sampled included recharge  intermediate  and discharge zones of a 100  000-km2 internally-draining province  known as the Death Valley Regional Flow System (DVRFS)  which encompasses the entirety of the NNSS/NTTR and surrounding areas. Specific geological features sampled included: West Pahute and Ranier Mesas (recharge zone)  Yucca and Frenchman Flats (transitional zone)  and the Western edge of the Amargosa Valley near Death Valley (discharge zone). The original overarching question underlying the proposal supporting this work was stated as: Can radiochemically-produced substrates support indigenous microbial communities and subsequently stimulate biocolloid formation that can affect radionuclides in NNSS subsurface nuclear test/detonation sites? Radioactive and non-radioactive groundwater samples were thus characterized for physical parameters  aqueous geochemistry  and microbial communities using both DNA- and cultivation-based tools in an effort to understand the drivers of microbial community structure (including radioactivity) and microbial interactions with select radionuclides and other factors across the range of habitats surveyed.