Preprints
Filtering by Subject: Life Sciences
Airborne laser scanning proxies of canopy light transmission in forests
Published: 2021-10-29
Subjects: Biodiversity, Biogeochemistry, Computer Sciences, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences, Software Engineering, Statistics and Probability
Reliable estimates of canopy light transmission are critical to understanding the structure and function of vegetation communities but are difficult and costly to attain by traditional field inventory methods. Airborne laser scanning (ALS) data uniquely provide multi-angular vertically resolved representation of canopy geometry across large geographic areas. While previous studies have proposed [...]
Bridging knowledge gaps with hybrid machine-learning forest ecosystem models (ML-FEMs): inferential simulation of past understory light regimes
Published: 2021-10-29
Subjects: Artificial Intelligence and Robotics, Biodiversity, Biogeochemistry, Computer Sciences, Earth Sciences, Ecology and Evolutionary Biology, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences
Soil moisture is a key limiting factor of plant productivity in boreal and montane regions, producing additional climate feedbacks through evaporation, regeneration, mortality, and respiration. Understory solar irradiation – the primary driver of surface temperature and evaporative demand – remains poorly represented in vegetation models due to a lack of 3-D canopy geometry. Existing models are [...]
Simulated decline of a northern forest due to anthropogenic controls on the regeneration-mortality balance
Published: 2021-10-29
Subjects: Biodiversity, Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences
The population structure of forests is shaped by balancing the opposing forces of regeneration and mortality, each of which influence C turnover rates and are sensitive to climate. Regeneration underlies the migrational potential of forests to climatic change and remains underserved in modeling studies. Our objective was to test the hypothesis that warming may reduce tree regeneration rates while [...]
Emergence of anthropogenic fire regimes in the southern boreal of Canada
Published: 2021-10-29
Subjects: Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Plant Sciences
While radiative forcing and thus land surface temperatures have been shown to positively correlate with fire severity, precipitation, and lightning strike frequency, the effects of human activity on fire regimes remain difficult to disentangle from geophysical drivers given co-variation between these factors. Here, I analyze fire regimes in the 1919-2012 period across Canada and compare national [...]
Tidal marsh resilience to sea level rise controlled by vertical accretion and landward migration under nature-based human adaptation scenarios
Published: 2021-10-16
Subjects: Biodiversity, Ecology and Evolutionary Biology, Environmental Studies, Geography, Life Sciences, Marine Biology, Plant Sciences
Tidal marshes are not only lost to human disturbance but also face the threat of sea level rise (SLR). However, current earth system models used to estimate future changes in wetland extent omit wetland’s real responses to SLR without field observations. We synthesised global data on sediment accretion rate (SAR) and surface elevation change (SEC) for tidal marshes and developed a mathematical [...]
Desiccation of the Transboundary Hamun Lakes between Iran and Afghanistan in Response to Hyro-climatic Droughts and Anthropogenic Activities
Published: 2021-10-13
Subjects: Engineering, Life Sciences
This paper investigates the hydro-climatic reasons behind the desiccation of the Hamun Lakes in the Iran-Afghanistan border. We analyzed changes in the flow of the Hirmand River (90 percent of the total inflow to the lakes) at the international border, and precipitation over this river’s sub-basin during 1960-2016 by calculating standardized indices for precipitation (SPI) and discharge (SDI). We [...]
Sand-capping stabilizes muddy sediment and improves benthic light conditions in eutrophic estuaries: laboratory verification and the potential for recovery of eelgrass (Zostera marina)
Published: 2021-10-12
Subjects: Life Sciences, Physical Sciences and Mathematics
Decades of eutrophication have increased water turbidity in Danish estuaries and led to light limitation of eelgrass (Zostera marina) growth. Former eelgrass areas are now denuded and consist of organic-rich muddy sediment with frequent resuspension events that maintain a high turbidity state. In addition, low anchoring capacity of eelgrass in the soft organic-rich sediments has contributed to [...]
Sustainability without geology? A shortsighted approach
Published: 2021-10-04
Subjects: Education, Life Sciences, Physical Sciences and Mathematics
Over the last few decades, the concept of sustainability has been proposed and championed as the answer to the impending challenges our society will be facing in the future. It has been a rallying opportunity for the broad earth sciences community and a good starting point for such a community to impact societal and policy decisions; however, it has been an opportunity we have largely missed thus [...]
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), [...]