Preprints
Filtering by Subject: Life Sciences
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: 2021-06-12
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: 2021-05-09
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: 2021-03-13
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 [...]
Rise and fall of vegetation primary production resilience to climate variability anticipated by a large ensemble of Earth System Models’ simulations
Published: 2021-03-10
Subjects: Life Sciences
Climate change is affecting many aspects of natural ecosystems and society. Anticipating the changes in vegetation resilience – the plants’ capacity to cope with disturbances and shocks such as those related to climate variability and extremes – is critical to understand and project ecosystems’ responses to global change and the impacts on the related ecosystem services, to support mitigation [...]
A baseline for microplastic particle occurrence and distribution in Great Bay Estuary
Published: 2021-02-19
Subjects: Life Sciences, Physical Sciences and Mathematics
We extracted and analyzed microplastics (MP) in archived sediment cores from Great Bay Estuary (GBE) in the Gulf of Maine region of North America. Results indicated that MP are distributed in GBE sediments, 0-30 cm, at an average occurrence of 116 ± 21 particles g-1 and that morphology varies by site and depth. Analysis by sediment depth and age class indicated that MP accumulation increased over [...]
Biological albedo reduction on ice sheets, glaciers, and snowfields
Published: 2021-01-30
Subjects: Life Sciences
The global cryosphere, Earth’s frozen water, is in precipitous decline. The ongoing and predicted impacts of cryosphere loss are diverse, ranging from disappearance of entire biomes to crises of water availability. Covering approximately one-fifth of the Earth, mass loss from the terrestrial cryosphere is driven primarily by a warming atmosphere but reductions in albedo (the proportion of [...]
Urban Running Activity Detected Using a Seismic Sensor duringCOVID-19 Pandemic
Published: 2021-01-30
Subjects: Engineering, Life Sciences, Social and Behavioral Sciences
Human foot traffic in urban environments provides essential information for city planners to manage the urban resources and urban residents to plan their activities. Compared to camera or mobile-based solutions, seismic sensors detect human footstep signals with fewer privacy concerns. However, seismic sensors often record signals generated from multiple sources, particularly in an urban outdoor [...]
Given that the Paris Agreement is unlikely to prevent dangerous climate overshoot, an alternative risk management strategy is urgently needed
Published: 2020-12-18
Subjects: Life Sciences, Physical Sciences and Mathematics, Social and Behavioral Sciences
Because the 2015 Paris Agreement will not prevent dangerous climate change, there is an urgent need to develop an alternative mitigation strategy. Even if most countries greatly increase their commitments and technological breakthroughs accelerate the transition to emission-free technologies, the 2°C target will still be overshot due to systemic inertia from existing greenhouse gases, warming [...]
Planted mangroves cap toxic oil spill
Published: 2020-12-07
Subjects: Life Sciences
Mangroves are known to provide many ecosystem services, however there is little information on their potential role to cap and immobilise toxic levels of total petroleum hydrocarbons (TPH). Using an Australian case study, we investigated the capacity of planted mangroves (Avicennia marina) to immobilise TPH within a small embayment subjected to multiple oil spills throughout the 1980s. Mangroves [...]
High-resolution downscaled CMIP5 projections dataset of essential surface climate variables over Europe coherent with ERA5-Land reanalyses for climate change impact assessments
Published: 2020-11-27
Subjects: Engineering, Life Sciences, Physical Sciences and Mathematics
A high-resolution climate projections dataset is obtained by statistically downscaling climate projections from the CMIP5 experiment using the ERA5-Land reanalyses from the Copernicus Climate Change service. The dataset is over Europe, has a spatial resolution of 0.10° x 0.10°, comprises 21 climate models and includes 5 surface daily variables: air temperature (mean, minimum, and maximum), [...]