Preprints
Filtering by Subject: Life Sciences
GAIANIZING DARWIN: NATURAL SELECTION IMPAIRS THE EFFECTIVENESS OF PLANETARY TEMPERATURE SELF-REGULATION
Published: 2021-09-11
Subjects: Life Sciences
Many neo-Darwinists have rejected the Gaia hypothesis, arguing that organisms cannot reach a common good by natural selection and that natural selection cannot act on the whole planet. In response, Watson and Lovelock put forward a model they called Daisyworld (Dw), a hypothetical planet which can regulate its temperature over a wide range of solar luminosities. This is accomplished by ordinary [...]
A re-evaluation of wetland carbon sink mitigation concepts and measurements: A diagenetic solution
Published: 2021-09-10
Subjects: Life Sciences
The capacity of wetlands to mitigate greenhouse gas (GHG) emissions is the sum of two services–the protection of vulnerable organic stocks from remineralisation, and the capacity to sequester GHGs relative to their anthropogenic replacements. Organic carbon accumulation (CA) down through the sediment column is often taken as the measure of sequestration because of its capacity to record long-term [...]
The spatial dynamics of wheat yield and protein content at the field scale
Published: 2021-09-09
Subjects: Agriculture, Ecology and Evolutionary Biology, Life Sciences
Wheat is a staple crop that is critical for feeding a hungry and growing planet, but its nutritive value has declined as global temperatures have warmed. The price offered to producers depends not only on yield but also grain protein content (GPC), which are often negatively related at the field scale but can positively covary depending in part on management strategies, emphasizing the need to [...]
The ‘europium anomaly’ in plants: facts and fiction
Published: 2021-09-08
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Life Sciences, Plant Sciences
Aims Rare earth elements (REEs) and normalized REE patterns determined in plant and soil samples represent powerful tools to trace biogeochemical processes during weathering, soil genesis and processes in the rhizosphere, and thus publications reporting rare earth elements and normalized REE patterns in soil systems and plants are rapidly increasing. Methods A normalized REE pattern allows [...]
Safety and Belonging in the Field: A Checklist for Educators
Published: 2021-08-19
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Cosmochemistry, Earth Sciences, Education, Environmental Education, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Environmental Studies, Fresh Water Studies, Geochemistry, Geographic Information Sciences, Geography, Geology, Geomorphology, Geophysics and Seismology, Glaciology, Higher Education, Human Geography, Hydrology, Life Sciences, Meteorology, Mineral Physics, Natural Resource Economics, Natural Resources and Conservation, Natural Resources Management and Policy, Nature and Society Relations, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Oil, Gas, and Energy, Other Earth Sciences, Other Environmental Sciences, Other Geography, Other Oceanography and Atmospheric Sciences and Meteorology, Other Planetary Sciences, Outdoor Education, Paleobiology, Paleontology, Physical and Environmental Geography, Physical Sciences and Mathematics, Planetary Biogeochemistry, Planetary Geochemistry, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Planetary Glaciology, Planetary Hydrology, Planetary Mineral Physics, Planetary Sciences, Planetary Sedimentology, Remote Sensing, Sedimentology, Social and Behavioral Sciences, Soil Science, Spatial Science, Speleology, Stratigraphy, Sustainability, Tectonics and Structure, Volcanology, Water Resource Management
Ensuring taught fieldwork is a positive, generative, collective, and valuable experience for all participants requires considerations beyond course content. To guarantee safety and belonging, participants’ identities (backgrounds and protected characteristics) must be considered as a part of fieldwork planning and implementation. Furthermore, getting fieldwork right is an important step in [...]
Impact of 8th October 2005 Earthquake Associated with Kashmir Boundary Thrust (KBT), Pakistan
Published: 2021-07-29
Subjects: Life Sciences
An earthquake on Richter scale of 7.6 intensity, originated from part of a fault zone more than 200 km long between Balakot and Reasi region of Jammu. This fault joins Indus Kohistan Seismic Zone (IKSZ). The epicenter was 11 km North - Northeast of Muzaffarabad while the depth was 15 km. The rupture zone along Kashmir Boundary Thrust was about 70 km in length. The area of impact is predominantly [...]
C:N:P stoichiometry in six distinct habitats of a glacier terminus in the Yangtze River Source Area
Published: 2021-07-01
Subjects: Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Glaciology, Life Sciences, Other Environmental Sciences, Sustainability
Glaciers are among the least explored environments on Earth, especially from a perspective of nutrient stoichiometry. In this study, we documented and compared the nutrient availabilities (concentrations) and composition (stoichiometric ratios) of nutrients (C, N, and P) in six distinct habitats of a glacier terminus in the Yangtze River Source area, including surface ice (SI), basal ice (BI), [...]
Colonial history and global economics distort our understanding of deep-time biodiversity
Published: 2021-06-24
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Life Sciences, Paleobiology, Paleontology, Physical Sciences and Mathematics
Sampling variations in the fossil record distort estimates of past biodiversity. However, compilations of global fossil occurrences used in these analyses not only reflect the geological and spatial aspects of the fossil record, but also the historical collation of these data. Here, we demonstrate how the legacy of colonialism as well as socio-economic factors such as wealth, education and [...]
Mapping carbon stocks in Central and South America with SMAP vegetation optical depth
Published: 2021-06-11
Subjects: Engineering, Life Sciences
Mapping carbon stocks in the tropics is essential for climate change mitigation. Passive microwave remote sensing allows estimating carbon from deep canopy layers through the Vegetation Optical Depth (VOD) parameter. Although their spatial resolution is coarser than that of optical vegetation indices or airborne Lidar data, microwaves present a higher penetration capacity at low frequencies [...]
An occurrence of radially-symmetric sedimentary structures in the basal Ediacaran cap dolostone (Keilberg Member) of the Otavi Group
Published: 2021-06-02
Subjects: Life Sciences, Physical Sciences and Mathematics
Snowball Earth cap carbonate sequences provide an archive of what are likely the most dramatic climate transitions in all of Earth history. One approach to gain insight into these events is the detailed observation of sedimentary structures within these post-glacial units. Here, we report on newly discovered radially-symmetric sedimentary structures within the Keilberg Member post-Marinoan ‘cap [...]
Photochemical synthesis of ammonia and amino acids from nitrous oxide
Published: 2021-05-26
Subjects: Life Sciences
Abiotic synthesis of ammonia and amino acids are important for origin of life and early evolution. Ammonia (NH3) and organic nitrogen species may be possibly produced from nitrous oxide (N2O), which is a second abundant nitrogen species in the atmosphere. Here, we report a new photochemical experiment and evaluate whether N2O can be used as a nitrogen source for prebiotic synthesis in the [...]
Simulating land use change trajectories of the Cerrado Hotspot reveals the importance of considering private property sizes for biodiversity conservation
Published: 2021-05-24
Subjects: Life Sciences
Simulating future land use changes can be an important tool to support decisionmaking, especially in areas that are experiencing rapid anthropogenic pressure, such as the Cerrado – Brazilian savanna. Here we used a spatially-explicit model to identify the main drivers of native vegetation loss in the Cerrado, and then projected this loss for 2050 and 2070. We also analyzed the role of [...]
A re-examination of the mechanism of whiting events: A new role for diatoms in Fayetteville Green Lake (New York, USA)
Published: 2021-05-08
Subjects: Biogeochemistry, Environmental Microbiology and Microbial Ecology Life Sciences, Geochemistry, Life Sciences, Sedimentology
Whiting events – the episodic precipitation of fine-grained suspended calcium cabonates in the water column – have been documented across a variety of marine and lacustrine environments. Whitings likely are a major source of carbonate muds, a constituent of limestones, and important archives for geochemical proxies of Earth history. While several biological and physical mechanisms have been [...]
Revision of thelodonts, acanthodians, conodonts, and the depositional environments in the Burgen outlier (Ludlow, Silurian) of Gotland, Sweden
Published: 2021-04-20
Subjects: Biodiversity, Earth Sciences, Ecology and Evolutionary Biology, Life Sciences, Physical Sciences and Mathematics
Ludfordian strata exposed in the Burgen outlier in eastern Gotland record a time of initial faunal recovery after a global environmental perturbation manifested in the Ludfordian Carbon Isotope Excursion (LCIE). Vertebrate microfossils in the collection of the late Lennart Jeppsson, hosted at the Swedish Museum of Natural History, hold the key to reconstruct the dynamics of faunal immigration and [...]
High resolution, annual maps of field boundaries for smallholder-dominated croplands at national scales
Published: 2021-03-12
Subjects: Agriculture, Environmental Monitoring, Environmental Sciences, Geographic Information Sciences, Geography, Life Sciences, Natural Resources and Conservation, Physical and Environmental Geography, Physical Sciences and Mathematics, Remote Sensing, Spatial Science, Sustainability
Mapping the characteristics of Africa's smallholder-dominated croplands, including the sizes and numbers of fields, can provide critical insights into food security and a range of other socioeconomic and environmental concerns. However, accurately mapping these systems is difficult because there is 1) a spatial and temporal mismatch between satellite sensors and smallholder fields, and 2) a lack [...]