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Full-Text Articles in Life Sciences

A Novel Ruminant Emission Measurement System: Part Ii. Commissioning, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Yi Sun, Luis F. Rodríguez, Daniel W. Shike, Richard S. Gates Aug 2019

A Novel Ruminant Emission Measurement System: Part Ii. Commissioning, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Yi Sun, Luis F. Rodríguez, Daniel W. Shike, Richard S. Gates

Brett Ramirez

The Ruminant Emission Measurement System (REMS) supports research on the relationships between bovine nutrition, genetics, and management strategies by measuring eructated CH4 emissions from ruminal activity. Part I of this series provides the description and design evaluation of the newly developed REMS using uncertainty analysis tools. Part II of this series describes REMS commissioning and documents the whole system and subsystem performance. Subsystem assessments included verification of chamber positive pressurization, thermal environmental control performance, and integrity of the gas sampling system. Integrity of the entire system was verified through a steady-state mass recovery percent (SSMRP) analysis, which compared the ...


A Novel Ruminant Emission Measurement System: Part I. Design Evaluation And Description, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Luis F. Rodríguez, Jacob R. Segers, Daniel W. Shike, Richard S. Gates Aug 2019

A Novel Ruminant Emission Measurement System: Part I. Design Evaluation And Description, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Luis F. Rodríguez, Jacob R. Segers, Daniel W. Shike, Richard S. Gates

Brett Ramirez

Methane (CH4) generated by cattle is both a major source of greenhouse gas emissions and a powerful indicator of feed conversion efficiency; thus, accurate quantification of CH4 production is required for addressing future global food security without neglecting environmental impacts. A newly developed Ruminant Emission Measurement System (REMS) supports research on the relationships between bovine nutrition, genetics, and management strategies by measuring eructated CH4 emissions from ruminal activity. REMS is a substantial improvement and extension of the chamber technique, which is considered the standard method to quantify ruminant CH4 generation. Part I of this two-part series describes the design and ...


Climate Change Impacts On Winter Wheat Yield In Northern China, Xiu Geng, Fang Wang, Wei Ren, Zhixin Hao Jun 2019

Climate Change Impacts On Winter Wheat Yield In Northern China, Xiu Geng, Fang Wang, Wei Ren, Zhixin Hao

Plant and Soil Sciences Faculty Publications

Exploring the impacts of climate change on agriculture is one of important topics with respect to climate change. We quantitatively examined the impacts of climate change on winter wheat yield in Northern China using the Cobb–Douglas production function. Utilizing time-series data of agricultural production and meteorological observations from 1981 to 2016, the impacts of climatic factors on wheat production were assessed. It was found that the contribution of climatic factors to winter wheat yield per unit area (WYPA) was 0.762–1.921% in absolute terms. Growing season average temperature (GSAT) had a negative impact on WYPA for the ...


Assessment Of Agricultural Drought Considering The Hydrological Cycle And Crop Phenology In The Korean Peninsula, Chul-Hee Lim, Seung Hee Kim, Jong Ahn Chun, Menas Kafatos, Woo-Kyun Lee May 2019

Assessment Of Agricultural Drought Considering The Hydrological Cycle And Crop Phenology In The Korean Peninsula, Chul-Hee Lim, Seung Hee Kim, Jong Ahn Chun, Menas Kafatos, Woo-Kyun Lee

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hydrological changes attributable to global warming increase the severity and frequency of droughts, which in turn affect agriculture. Hence, we proposed the Standardized Agricultural Drought Index (SADI), which is a new drought index specialized for agriculture and crops, and evaluated current and expected droughts in the Korean Peninsula. The SADI applies crop phenology to the hydrological cycle, which is a basic element that assesses drought. The SADI of rice and maize was calculated using representative hydrological variables (precipitation, evapotranspiration, and runoff) of the crop growing season. In order to evaluate the effectiveness of SADI, the three-month Standardized Precipitation Index, which ...


Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias May 2019

Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias

Electronic Theses and Dissertations

Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi, which is transmitted through the bite of an infected blacklegged (deer) tick (Ixodes scapularis). Geographic invasion of I. scapularis in North America has been attributed to causes including 20th century reforestation and suburbanization, burgeoning populations of the white-tailed deer (Odocoileus virginianus) which is the primary reproductive host of I. scapularis, tick-associated non-native plant invasions, and climate change. Maine, USA, is a high Lyme disease incidence state, with a history of increasing I. scapularis abundance and northward range expansion. This thesis addresses the question: “To what extent has the range expansion ...


Effects Of Increased Precipitation On The Life History Of Spring- And Autumn-Germinated Plants Of The Cold Desert Annual Erodium Oxyrhynchum (Geraniaceae), Yanfeng Chen, Xiang Shi, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Huiliang Liu, Daoyuan Zhang Apr 2019

Effects Of Increased Precipitation On The Life History Of Spring- And Autumn-Germinated Plants Of The Cold Desert Annual Erodium Oxyrhynchum (Geraniaceae), Yanfeng Chen, Xiang Shi, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Huiliang Liu, Daoyuan Zhang

Biology Faculty Publications

Future increased precipitation in cold desert ecosystems may impact annual/ephemeral plant species that germinate in both spring and autumn. Our primary aim was to compare the life history characteristics of plants from spring-germinating (SG) and autumn-germinating (AG) seeds of Erodium oxyrhynchum. Plants in field plots with simulated increases in precipitation of 0, 30 and 50 % in spring and summer were monitored to determine seedling survival, phenology, plant size, seed production and biomass accumulation and allocation. Germination characteristics were determined in the laboratory for seeds produced by plants in all increased precipitation treatments. Increased precipitation in spring significantly improved survival ...


Creative Citizen Science Illuminates Complex Ecological Responses To Climate Change, Abraham J. Miller-Rushing, Amanda S. Gallinat, Richard B. Primack Jan 2019

Creative Citizen Science Illuminates Complex Ecological Responses To Climate Change, Abraham J. Miller-Rushing, Amanda S. Gallinat, Richard B. Primack

Biology Faculty Publications

Climate change is causing the timing of key behaviors (i.e., phenology) to shift differently across trophic levels and among some interacting organisms (e.g., plants and pollinators, predators and prey), suggesting that interactions among species are being disrupted (1, 2). Studying the phenology of interactions, however, is difficult, which has limited researchers’ ability to zero in on changes in specific interactions or on the consequences of mismatches. In PNAS, Hassall et al. (3) use a combination of citizen science techniques to investigate the effects of climate change on dozens of specific interactions. They focus on a Batesian mimicry complex ...