Browsing by Author "Reba, Michele L."
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Item Socio-Technical Changes for Sustainable Rice Production: Rice Husk Amendment, Conservation Irrigation, and System Changes(Frontiers in Agronomy, 2021-10-22) Runkle, Benjamin R. K.; Seyfferth, Angelia L.; Reid, Matthew C.; Limmer, Matthew A.; Moreno-García, Beatriz; Reavis, Colby W. Reavis; Peña, Jasquelin; Reba, Michele L.; Adviento-Borbe, M. Arlene A.; Pinson, Shannon R. M.; Isbell, ChrisRice is a staple food and primary source of calories for much of the world. However, rice can be a dietary source of toxic metal(loid)s to humans, and its cultivation creates atmospheric greenhouse gas emissions and requires high water use. Because rice production consumes a significant amount of natural resources and is a large part of the global agricultural economy, increasing its sustainability could have substantial societal benefits. There are opportunities for more sustainable field production through a combination of silicon (Si) management and conservation irrigation practices. As a Si-rich soil amendment, rice husks can limit arsenic and cadmium uptake, while also providing plant vigor in drier soil conditions. Thus, husk addition and conservation irrigation may be more effective to attenuate the accumulation of toxic metal(loid)s, manage water usage and lower climate impacts when implemented together than when either is implemented separately. This modified field production system would take advantage of rice husks, which are an underutilized by-product of milled rice that is widely available near rice farm sites, and have ~10% Si content. Husk application could, alongside alternate wetting and drying or furrow irrigation management, help resolve multiple sustainability challenges in rice production: (1) limit arsenic and cadmium accumulation in rice; (2) minimize greenhouse gas emissions from rice production; (3) decrease irrigation water use; (4) improve nutrient use efficiency; (5) utilize a waste product of rice processing; and (6) maintain plant-accessible soil Si levels. This review presents the scientific basis for a shift in rice production practices and considers complementary rice breeding efforts. It then examines socio-technical considerations for how such a shift in production practices could be implemented by farmers and millers together and may bring rice production closer to a bio-circular economy. This paper's purpose is to advocate for a changed rice production method for consideration by community stakeholders, including producers, millers, breeders, extension specialists, supply chain organizations, and consumers, while highlighting remaining research and implementation questions.Item Substantial hysteresis in emergent temperature sensitivity of global wetland CH4 emissions(Nature Communications, 2021-04-15) Chang, Kuang-Yu; Riley, William J.; Knox, Sara H.; Jackson, Robert B.; McNicol, Gavin; Poulter, Benjamin; Aurela, Mika; Baldocchi, Dennis; Bansal, Sheel; Bohrer, Gil; Campbell, David I.; Cescatti, Alessandro; Chu, Housen; Delwiche, Kyle B.; Desai, Ankur R.; Euskirchen, Eugenie; Friborg, Thomas; Goeckede, Mathias; Helbig, Manuel; Hemes, Kyle S.; Hirano, Takashi; Iwata, Hiroki; Kang, Minseok; Keenan, Trevor; Krauss, Ken W.; Lohila, Annalea; Mammarella, Ivan; Mitra, Bhaskar; Miyata, Akira; Nilsson, Mats B.; Noormets, Asko; Oechel, Walter C.; Papale, Dario; Peichl, Matthias; Reba, Michele L.; Rinne, Janne; Runkle, Benjamin R. K.; Ryu, Youngryel; Sachs, Torsten; Schäfer, Karina V. R.; Schmid, Hans Peter; Shurpali, Narasinha; Sonnentag, Oliver; Tang, Angela C. I.; Torn, Margaret S.; Trotta, Carlo; Tuittila, Eeva-Stiina; Ueyama, Masahito; Vargas, Rodrigo; Vesala, Timo; Windham-Myers, Lisamarie; Zhang, Zhen; Zona, DonatellaWetland methane (CH4) emissions (FCH4) are important in global carbon budgets and climate change assessments. Currently, FCH4 projections rely on prescribed static temperature sensitivity that varies among biogeochemical models. Meta-analyses have proposed a consistent FCH4 temperature dependence across spatial scales for use in models; however, site-level studies demonstrate that FCH4 are often controlled by factors beyond temperature. Here, we evaluate the relationship between FCH4 and temperature using observations from the FLUXNET-CH4 database. Measurements collected across the globe show substantial seasonal hysteresis between FCH4 and temperature, suggesting larger FCH4 sensitivity to temperature later in the frost-free season (about 77% of site-years). Results derived from a machine-learning model and several regression models highlight the importance of representing the large spatial and temporal variability within site-years and ecosystem types. Mechanistic advancements in biogeochemical model parameterization and detailed measurements in factors modulating CH4 production are thus needed to improve global CH4 budget assessments.