Browsing by Author "Hamilton, Stephen K."
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Increased floodplain inundation in the Amazon since 1980Fleischmann, Ayan S.; Papa, Fabrice; Hamilton, Stephen K.; Fassoni-Andrade, Alice; Wongchuig, Sly; Espinoza, Jhan-Carlo; Paiva, Rodrigo C. D.; Melack, John M.; Fluet-Chouinard, Etienne; Castello, Leandro; Almeida, Rafael M.; Bonnet, Marie-Paule; Alves, Luna G.; Moreira, Daniel; Yamazaki, Dai; Revel, Menaka; Collischonn, Walter (IOP Publishing, 2023-03-01)Extensive floodplains throughout the Amazon basin support important ecosystem services and influence global water and carbon cycles. A recent change in the hydroclimatic regime of the region, with increased rainfall in the northern portions of the basin, has produced record-breaking high water levels on the Amazon River mainstem. Yet, the implications for the magnitude and duration of floodplain inundation across the basin remain unknown. Here we leverage state-of-the-art hydrological models, supported by in-situ and remote sensing observations, to show that the maximum annual inundation extent along the central Amazon increased by 26% since 1980. We further reveal increased flood duration and greater connectivity among open water areas in multiple Amazon floodplain regions. These changes in the hydrological regime of the world's largest river system have major implications for ecology and biogeochemistry, and require rapid adaptation by vulnerable populations living along Amazonian rivers.
- Linking soil microbial community structure to potential carbon mineralization: A continental scale assessment of reduced tillageRieke, Elizabeth L.; Cappellazzi, Shannon B.; Cope, Michael; Liptzin, Daniel; Mac Bean, G.; Greub, Kelsey L. H.; Norris, Charlotte E.; Tracy, Paul W.; Aberle, Ezra; Ashworth, Amanda; Banuelos Tavarez, Oscar; Bary, Andy, I; Baumhardt, R. L.; Borbon Gracia, Alberto; Brainard, Daniel C.; Brennan, Jameson R.; Briones Reyes, Dolores; Bruhjell, Darren; Carlyle, Cameron N.; Crawford, James J. W.; Creech, Cody F.; Culman, Steve W.; Deen, Bill; Dell, Curtis J.; Derner, Justin D.; Ducey, Thomas F.; Duiker, Sjoerd W.; Dyck, Miles F.; Ellert, Benjamin H.; Espinosa Solorio, Avelino; Fonte, Steven J.; Fonteyne, Simon; Fortuna, Ann-Marie; Foster, Jamie L.; Fultz, Lisa M.; Gamble, Audrey, V; Geddes, Charles M.; Griffin-LaHue, Deirdre; Grove, John H.; Hamilton, Stephen K.; Hao, Xiying; Hayden, Zachary D.; Honsdorf, Nora; Howe, Julie A.; Ippolito, James A.; Johnson, Gregg A.; Kautz, Mark A.; Kitchen, Newell R.; Kumar, Sandeep; Kurtz, Kirsten S. M.; Larney, Francis J.; Lewis, Katie L.; Liebman, Matt; Lopez Ramirez, Antonio; Machado, Stephen; Maharjan, Bijesh; Martinez Gamino, Miguel Angel; May, William E.; McClaran, Mitchel P.; McDaniel, Marshall D.; Millar, Neville; Mitchell, Jeffrey P.; Moore, Amber D.; Moore, Philip A.; Mora Gutierrez, Manuel; Nelson, Kelly A.; Omondi, Emmanuel C.; Osborne, Shannon L.; Osorio Alcala, Leodegario; Owens, Philip; Pena-Yewtukhiw, Eugenia M.; Poffenbarger, Hanna J.; Ponce Lira, Brenda; Reeve, Jennifer R.; Reinbott, Timothy M.; Reiter, Mark S.; Ritchey, Edwin L.; Roozeboom, Kraig L.; Rui, Yichao; Sadeghpour, Amir; Sainju, Upendra M.; Sanford, Gregg R.; Schillinger, William F.; Schindelbeck, Robert R.; Schipanski, Meagan E.; Schlegel, Alan J.; Scow, Kate M.; Sherrod, Lucretia A.; Shober, Amy L.; Sidhu, Sudeep S.; Solis Moya, Ernesto; St Luce, Mervin; Strock, Jeffrey S.; Suyker, Andrew E.; Sykes, Virginia R.; Tao, Haiying; Trujillo Campos, Alberto; Van Eerd, Laura L.; Verhulst, Nele; Vyn, Tony J.; Wang, Yutao; Watts, Dexter B.; William, Bryan B.; Wright, David L.; Zhang, Tiequan; Morgan, Cristine L. S.; Honeycutt, C. Wayne (Pergamon-Elsevier, 2022-05)Potential carbon mineralization (Cmin) is a commonly used indicator of soil health, with greater Cmin values interpreted as healthier soil. While Cmin values are typically greater in agricultural soils managed with minimal physical disturbance, the mechanisms driving the increases remain poorly understood. This study assessed bacterial and archaeal community structure and potential microbial drivers of Cmin in soils maintained under various degrees of physical disturbance. Potential carbon mineralization, 16S rRNA sequences, and soil characterization data were collected as part of the North American Project to Evaluate Soil Health Measurements (NAPESHM). Results showed that type of cropping system, intensity of physical disturbance, and soil pH influenced microbial sensitivity to physical disturbance. Furthermore, 28% of amplicon sequence variants (ASVs), which were important in modeling Cmin, were enriched under soils managed with minimal physical disturbance. Sequences identified as enriched under minimal disturbance and important for modeling Cmin, were linked to organisms which could produce extracellular polymeric substances and contained metabolic strategies suited for tolerating environmental stressors. Understanding how physical disturbance shapes microbial communities across climates and inherent soil properties and drives changes in Cmin provides the context necessary to evaluate management impacts on standardized measures of soil microbial activity.