Physical Sciences and Mathematics | Open Access Articles

Extensive Tissue-Specific Transcriptomic Plasticity In Maize Primary Roots Upon Water Deficit, Nina Opitz, Caroline Marcon, Anja Paschold, Waqas Ahmed Malik, Andrew Lithio, Ronny Brandt, Hans-Peter Piepho, Dan Nettleton, Frank Hochholdinger

Dan Nettleton

Water deficit is the most important environmental constraint severely limiting global crop growth and productivity. This study investigated early transcriptome changes in maize (Zea mays L.) primary root tissues in response to moderate water deficit conditions by RNA-Sequencing. Differential gene expression analyses revealed a high degree of plasticity of the water deficit response. The activity status of genes (active/inactive) was determined by a Bayesian hierarchical model. In total, 70% of expressed genes were constitutively active in all tissues. In contrast, <3% (50 genes) of water deficit-responsive genes (1915) were consistently regulated in all tissues, while >75% (1501 genes) were specifically regulated in a single root tissue. Water deficit-responsive genes were most numerous in the …

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A Meteorological Analysis Of Important Contributions To The 1999-2005 Canadian Prairie Drought, Lisa M. Hryciw, Eyad H. Atallah, Shawn M. Milrad, John R. Gyakum

Shawn M. Milrad

Drought is a complex natural hazard that is endemic to the Canadian prairies. The 1999–2005 Canadian prairie drought, which had great socioeconomic impacts, was meteorologically unique in that it did not conform to the traditional persistent positive Pacific–North American (PNA) pattern and west coast ridging paradigm normally associated with prairie drought. The purpose of this study is to diagnose the unique synoptic-scale mechanisms responsible for modulating subsidence during this drought. Using 30-day running means of the percent of normal precipitation from station data, key severe dry periods during 1999–2005 are identified. Analysis of the mean fields from reanalysis data shows …

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A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu

Andy VanLoocke

Utility of perennial bioenergy crops (e.g., switchgrass and miscanthus) offers unique opportunities to transition toward a more sustainable energy pathway due to their reduced carbon footprint, averted competition with food crops, and ability to grow on abandoned and degraded farmlands. Studies that have examined biogeophysical impacts of these crops noted a positive feedback between near-surface cooling and enhanced evapotranspiration (ET), but also potential unintended consequences of soil moisture and groundwater depletion. To better understand hydrometeorological effects of perennial bioenergy crop expansion, this study conducted high-resolution (2-km grid spacing) simulations with a state-of-the-art atmospheric model (Weather Research and Forecasting system) dynamically …

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Sequias En El Sur De La Peninsula De Yucatan: Analisis De La Variabilidad Anual Y Estacional De La Precipitacion (Droughts In The Southern Yucatan Peninsula: Analysis Of The Annual And Seasonal Precipitation Variability), Sofia Mardero, Elsa Nickl, Birgit Schmook, Laura Schneider, John Rogan, Zachary Christman, Deborah Lawrence

Zachary Christman

Paper is in Spanish. English abstract: This study analyzes the spatial and temporal variability of precipitation across the Southern Yucatán Peninsula in Mexico, addressing the anomalies and trends of annual and seasonal precipitation as well as the occurrence of meteorological droughts, using rainfall data from nine weather stations during the period 1953-2007. Linear regression in the annual and seasonal rainfall were used to analyze the increase or decrease in precipitation trends over this period. Precipitation anomalies enabled the evaluation of the stability, deficit, or surplus of precipitation for each year or season, and a quintile method was used to …

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Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George C. Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Bevery E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker

Xiaoyang Zhang

The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection between the terrestrial biosphere and the Earth's climate. Despite the general agreement that the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution of the sink remain uncertain. We use a data-driven approach to upscale eddy covariance flux observations from towers to the continental scale by integrating flux observations, meteorology, stand age, aboveground biomass, and a proxy for canopy nitrogen concentrations from AmeriFlux and Fluxnet-Canada Research Network as well as a variety of satellite data streams from the MODIS …

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Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker

Xiaoyang Zhang

The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection between the terrestrial biosphere and the Earth’s climate. Despite the general agreement that the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution of the sink remain uncertain. We use a data-driven approach to upscale eddy covariance flux observations from towers to the continental scale by integrating flux observations, meteorology, stand age,aboveground biomass, and a proxy for canopy nitrogen concentrations from AmeriFlux and Fluxnet-Canada Research Network as well as a variety of satellite data streams from the MODIS sensors. …

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Geospatial Decision Support For Drought Risk Management , Steve Goddard, Sherri Harms, Stephen Reichenbach, Tsegaye Tadesse, William Waltman

Steve Reichenbach

Drought affects virtually all regions of the world and results in significant economic, social, and environmental impacts. The Federal Emergency Management Agency estimates annual drought-related losses in the U.S. at $6–$8 billion, which is more than any other natural hazard. Congress enacted the Agricultural Risk Protection Act of 2000 to encourage the U.S. Department of Agriculture (USDA) Risk Management Agency (RMA) and farmers to be more proactive in managing drought risk. Through the NSF’s Digital Government Program, the USDA RMA is working with the University of Nebraska–Lincoln Computer Science and Engineering Department, National Drought Mitigation Center (NDMC), and High Plains …

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Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond

Samuel K Marx

The Kimberley region of northwest Australia contains one of the World's largest collections of rock art characterised by two distinct art forms; the fine featured anthropomorphic figures of the Gwion Gwion or Bradshaw paintings, and broad stroke Wandjina figures. Luminescence dating of mud wasp nests overlying Gwion Gwion paintings has confirmed an age of at least 17,000 yrs B.P. with the most recent dates for these paintings from around the mid-Holocene (5000 to 7000 yrs B.P.). Radiocarbon dating indicates that the Wandjina rock art then emerged around 3800 to 4000 yrs B.P. following a hiatus of at least 1200 yrs. …

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The Effects Of The 2001-2002 Drought On Maine Surface Water Supplies, Catherine Schmitt

Catherine Schmitt

Maine lakes and streams serve as significant sources of public water supply, serving 40% of the population. Drought affects surface water resources by reducing water quantity and altering water quality, for example by reducing inputs of materials from the watershed and increasing water residence times. The 2001-2002 drought was the worst in Maine in over thirty years, and it exposed deficiencies in current water resources planning and management. In this study, I evaluated the effects of the 2001-2002 drought on Maine public water systems in order to identify characteristics of systems vulnerable to drought and determine appropriate indicators of drought …

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Geospatial Decision Support For Drought Risk Management , Steve Goddard, Sherri K. Harms, Stephen E. Reichenbach, Tsegaye Tadesse, William J. Waltman

Tsegaye Tadesse

Drought affects virtually all regions of the world and results in significant economic, social, and environmental impacts. The Federal Emergency Management Agency estimates annual drought-related losses in the U.S. at $6–$8 billion, which is more than any other natural hazard. Congress enacted the Agricultural Risk Protection Act of 2000 to encourage the U.S. Department of Agriculture (USDA) Risk Management Agency (RMA) and farmers to be more proactive in managing drought risk. Through the NSF’s Digital Government Program, the USDA RMA is working with the University of Nebraska–Lincoln Computer Science and Engineering Department, National Drought Mitigation Center (NDMC), and High Plains …

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Global Effects Of Climate Change On Wildfire: Causal Relationships Of Fire, The Natural Environment And Human Activities, Lindon N. Pronto

Lindon N Pronto

Climate change and human activity is significantly impacting the frequency and severity of wildfires across the globe. Although climate change and human population are the overarching factors affecting wildfires in the current dialogue, the issues are more complex and often not fully understood. These issues range from global temperature increases and severe drought cycles to the relatively new phenomenon of the wildland urban interface (WUI). This is the area where structures are integrated with or immediately surrounded by areas of moderate to high fire risk and are directly linked to fuel types and topographic features. Because climate change is such …

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Changing Cultures Of Water In Eastern Australian Backyard Gardens, Lesley M. Head, Pat Muir

Lesley Head

Research into diverse cultural understandings of water provides important contributions to the pressing global issue of sustainable supply, particularly when combined with analysis of relationships between everyday household practice and larger sociotechnical networks of storage and distribution. Here we analyse semi-structured interviews with 298 people about their 241 backyards in the Australian east coast cities of Sydney and Wollongong, undertaken during the 2002-03 drought. Water emerged as an important issue in both consciousness and practice. In contrast to a number of other environmental issues which stimulate more polarised responses, a commitment to reducing water consumption was shared across the study …

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Book Review: The Great Warming: Climate Change And The Rise And Fall Of Civilizations, James Fleming

James R. Fleming

No abstract provided.

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Full-Text Articles in Physical Sciences and Mathematics

Extensive Tissue-Specific Transcriptomic Plasticity In Maize Primary Roots Upon Water Deficit, Nina Opitz, Caroline Marcon, Anja Paschold, Waqas Ahmed Malik, Andrew Lithio, Ronny Brandt, Hans-Peter Piepho, Dan Nettleton, Frank Hochholdinger

Dan Nettleton

A Meteorological Analysis Of Important Contributions To The 1999-2005 Canadian Prairie Drought, Lisa M. Hryciw, Eyad H. Atallah, Shawn M. Milrad, John R. Gyakum

Shawn M. Milrad

A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu

Andy VanLoocke

Zachary Christman

Xiaoyang Zhang

Xiaoyang Zhang

Geospatial Decision Support For Drought Risk Management , Steve Goddard, Sherri Harms, Stephen Reichenbach, Tsegaye Tadesse, William Waltman

Steve Reichenbach

Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond

Samuel K Marx

The Effects Of The 2001-2002 Drought On Maine Surface Water Supplies, Catherine Schmitt

Catherine Schmitt

Geospatial Decision Support For Drought Risk Management , Steve Goddard, Sherri K. Harms, Stephen E. Reichenbach, Tsegaye Tadesse, William J. Waltman

Tsegaye Tadesse

Global Effects Of Climate Change On Wildfire: Causal Relationships Of Fire, The Natural Environment And Human Activities, Lindon N. Pronto

Lindon N Pronto

Changing Cultures Of Water In Eastern Australian Backyard Gardens, Lesley M. Head, Pat Muir

Lesley Head

Book Review: The Great Warming: Climate Change And The Rise And Fall Of Civilizations, James Fleming

James R. Fleming