scholarly journals Vegetation structure determines cyanobacterial communities during soil development across global biomes

2021 ◽  
Author(s):  
Concha Cano-Diaz ◽  
Fernando Tomas Maestre ◽  
Juntao Wang ◽  
Jing Li ◽  
Brajesh Singh ◽  
...  
Keyword(s):  
Vegetation Change ◽  
Field Survey ◽  
Temporal Dynamics ◽  
Soil Development ◽  
Vegetation Shifts ◽  
Extensive Field ◽  
Global Soil ◽  
Soil Age ◽  
Soil Cyanobacteria

Soil cyanobacteria play essential ecological roles and are known to experience large changes in their diversity and abundance throughout early succession. However, much less is known about how and why soil cyanobacterial communities change as soil develops from centuries to millennia, and the effects of aboveground vegetation on these communities. We combined an extensive field survey including 16 global soil chronosequences across contrasting ecosystems (from deserts to tropical forests) with molecular analyses to investigate how the diversity and abundance of soil cyanobacteria under vegetation change during soil development from hundreds to thousands of years. We show that, in most chronosequences, the abundance, species richness and community composition of soil cyanobacteria were relatively stable as soil develops (from centuries to millennia). Regardless of soil age, forest chronosequences were consistently dominated by non-photosynthetic cyanobacteria (Vampirovibrionia), while grasslands and shrublands were dominated by photosynthetic cyanobacteria. Chronosequences undergoing drastic vegetation shifts during soil development (e.g. transitions from grasslands to forests) experienced significant changes in the composition of soil cyanobacteria communities. Our results advance our understanding of the ecology of cyanobacterial classes, specially the understudied non-photosynthetic ones and highlight the key role of vegetation as a major driver of their temporal dynamics as soil develops.

scholarly journals Global soil moisture data derived through machine learning trained with in-situ measurements

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Sungmin O. ◽  
Rene Orth
Keyword(s):  
Machine Learning ◽  
Soil Moisture ◽  
Large Scale ◽  
Short Term Memory ◽  
Temporal Dynamics ◽  
Soil Moisture Data ◽  
Wide Range ◽  
Global Soil

AbstractWhile soil moisture information is essential for a wide range of hydrologic and climate applications, spatially-continuous soil moisture data is only available from satellite observations or model simulations. Here we present a global, long-term dataset of soil moisture derived through machine learning trained with in-situ measurements, SoMo.ml. We train a Long Short-Term Memory (LSTM) model to extrapolate daily soil moisture dynamics in space and in time, based on in-situ data collected from more than 1,000 stations across the globe. SoMo.ml provides multi-layer soil moisture data (0–10 cm, 10–30 cm, and 30–50 cm) at 0.25° spatial and daily temporal resolution over the period 2000–2019. The performance of the resulting dataset is evaluated through cross validation and inter-comparison with existing soil moisture datasets. SoMo.ml performs especially well in terms of temporal dynamics, making it particularly useful for applications requiring time-varying soil moisture, such as anomaly detection and memory analyses. SoMo.ml complements the existing suite of modelled and satellite-based datasets given its distinct derivation, to support large-scale hydrological, meteorological, and ecological analyses.

scholarly journals Corticostriatal control of defense behavior in mice induced by auditory looming cues

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhong Li ◽  
Jin-Xing Wei ◽  
Guang-Wei Zhang ◽  
Junxiang J. Huang ◽  
Brian Zingg ◽  
...  
Keyword(s):  
Essential Role ◽  
Neural Circuits ◽  
Temporal Dynamics ◽  
Defense Behavior ◽  
Innate Defense ◽  
Sensory Inputs ◽  
Corticostriatal Projections ◽  
Behavioral Transition ◽  
Auditory Looming

AbstractAnimals exhibit innate defense behaviors in response to approaching threats cued by the dynamics of sensory inputs of various modalities. The underlying neural circuits have been mostly studied in the visual system, but remain unclear for other modalities. Here, by utilizing sounds with increasing (vs. decreasing) loudness to mimic looming (vs. receding) objects, we find that looming sounds elicit stereotypical sequential defensive reactions: freezing followed by flight. Both behaviors require the activity of auditory cortex, in particular the sustained type of responses, but are differentially mediated by corticostriatal projections primarily innervating D2 neurons in the tail of the striatum and corticocollicular projections to the superior colliculus, respectively. The behavioral transition from freezing to flight can be attributed to the differential temporal dynamics of the striatal and collicular neurons in their responses to looming sound stimuli. Our results reveal an essential role of the striatum in the innate defense control.

The Role of Field Survey in the Identification of Farmland Abandonment in Slovakia Using Sentinel-2 Data

2021 ◽  
pp. 1-19
Author(s):  
Daniel Szatmári ◽  
Ján Feranec ◽  
Tomáš Goga ◽  
Miloš Rusnák ◽  
Monika Kopecká ◽  
...  
Keyword(s):  
Field Survey ◽  
Farmland Abandonment ◽  
Sentinel 2

A five-decade review of gender-based occupational segregation: A bibliometric study of influential authors, institutions, and research clusters

2021 ◽  
Vol 30 (2) ◽  
pp. 117-128
Author(s):  
Leena Sachdeva ◽  
Kumkum Bharti ◽  
Mridul Maheshwari
Keyword(s):  
Wage Differential ◽  
Web Of Science ◽  
Occupational Segregation ◽  
Extensive Field ◽  
Organisational Structures ◽  
Gender Based ◽  
Changes Over Time ◽  
Over Time ◽  
The Web

Despite the proliferation of occupational segregation research, only a limited amount has explored it from a gender perspective. The attention that has been given is widely scattered and requires an analysis to identify the major works undertaken and the changes over time. This study aimed to examine and assimilate articles published on gender-based occupational segregation through a bibliometric analysis. The study examined 512 articles published from the early 1970s to 2020 that were retrieved from the Web of Science database. The findings suggest that gender and occupational segregation remain an extensive field of research, although this research comes mainly from North American and European countries. The low representation from developing countries indicates that more research is needed based on these different socio-cultural settings. This study identified three dominant research clusters, namely gendered organisational structures and systems, measurement of occupational segregation, and wage differential. Studies also covered areas including conceptualization, LGBTQ issues, and the role of legislation and institutions in reducing workplace inequalities; thus, providing a direction for scholars and practitioners.

Evaluating the role of soil physical properties on simulated land-atmosphere interactions over South Africa using coupled atmosphere-hydrological modeling

2021 ◽  
Author(s):  
Zhenyu Zhang ◽  
Patrick Laux ◽  
Joël Arnault ◽  
Jianhui Wei ◽  
Jussi Baade ◽  
...  
Keyword(s):  
South Africa ◽  
Physical Properties ◽  
Land Degradation ◽  
Land Surface ◽  
Soil Physical Properties ◽  
Near Surface ◽  
Soil Database ◽  
Global Soil ◽  
The Impact

<p>Land degradation with its direct impact on vegetation, surface soil layers and land surface albedo, has great relevance with the climate system. Assessing the climatic and ecological effects induced by land degradation requires a precise understanding of the interaction between the land surface and atmosphere. In coupled land-atmosphere modeling, the low boundary conditions impact the thermal and hydraulic exchanges at the land surface, therefore regulates the overlying atmosphere by land-atmosphere feedback processes. However, those land-atmosphere interactions are not convincingly represented in coupled land-atmosphere modeling applications. It is partly due to an approximate representation of hydrological processes in land surface modeling. Another source of uncertainties relates to the generalization of soil physical properties in the modeling system. This study focuses on the role of the prescribed physical properties of soil in high-resolution land surface-atmosphere simulations over South Africa. The model used here is the hydrologically-enhanced Weather Research and Forecasting (WRF-Hydro) model. Four commonly used global soil datasets obtained from UN Food and Agriculture Organization (FAO) soil database, Harmonized World Soil Database (HWSD), Global Soil Dataset for Earth System Model (GSDE), and SoilGrids dataset, are incorporated within the WRF-Hydro experiments for investigating the impact of soil information on land-atmosphere interactions. The simulation results of near-surface temperature, skin temperature, and surface energy fluxes are presented and compared to observational-based reference dataset. It is found that simulated soil moisture is largely influenced by soil texture features, which affects its feedback to the atmosphere.</p>

The role of short-term weather conditions in temporal dynamics of fire regime features in mainland Spain

2019 ◽  
Vol 241 ◽  
pp. 575-586 ◽  
Author(s):  
Adrián Jiménez-Ruano ◽  
Marcos Rodrigues Mimbrero ◽  
W. Matt Jolly ◽  
Juan de la Riva Fernández
Keyword(s):  
Temporal Dynamics ◽  
Fire Regime ◽  
Weather Conditions ◽  
Short Term

THE ROLE OF PLANS IN THE FORMATION OF A NEW INNOVATION PRACTICE: AN INNOVATION OBJECT PERSPECTIVE

2019 ◽  
Vol 23 (04) ◽  
pp. 1950031
Author(s):  
SIW M. FOSSTENLØKKEN
Keyword(s):  
Significant Role ◽  
Current Practice ◽  
Temporal Dynamics ◽  
Ethnographic Study ◽  
Innovation Theory ◽  
Object Theory ◽  
Primary Object ◽  
Practice Development ◽  
Future Practice

This paper explores the role of plans, as objects, in the formation of new innovation practice in organisations. A vocabulary for analysis is developed from innovation object theory. First, findings from an ethnographic study in a hospital organisation show that a plan serves several functions depending on its activation for use: a checklist of past practice (tertiary object), an opener for debates over current practice (secondary object) and a trigger for future practice development (primary object). Second, a framework is offered that shows how a plan supports different functionalities (evaluating, debating, further exploring) in a temporal dynamics of practice formation. Third, thus, plans play a significant role not only in planning activities, but also as connectors that shape and patch together pieces of past, present and future into what actually become new organisational practice. Finally, implications for innovation theory and management are drawn from these novel contributions.

Role of small mammals in the persistence of Louping-ill virus: field survey and tick co-feeding studies

2000 ◽  
Vol 14 (3) ◽  
pp. 277-282 ◽  
Author(s):  
L. Gilbert ◽  
L. D. Jones ◽  
P. J. Hudson ◽  
E. A. Gould ◽  
H. W. Reid
Keyword(s):  
Small Mammals ◽  
Field Survey ◽  
Louping Ill

scholarly journals Biogeomorphic feedbacks and the ecosystem engineering of recently deglaciated terrain

2018 ◽  
Vol 43 (1) ◽  
pp. 24-45 ◽  
Author(s):  
Hannah R Miller ◽  
Stuart N Lane
Keyword(s):  
Environmental Stress ◽  
Ecosystem Engineer ◽  
Abiotic Factors ◽  
Ecosystem Engineering ◽  
Soil Development ◽  
Water Dynamics ◽  
Biotic Factors ◽  
Successional Stage ◽  
Abiotic And Biotic Factors

Matthews’ 1992 geoecological model of vegetation succession within glacial forefields describes how following deglaciation the landscape evolves over time as the result of both biotic and abiotic factors, with the importance of each depending on the level of environmental stress within the system. We focus in this paper on how new understandings of abiotic factors and the potential for biogeomorphic feedbacks between abiotic and biotic factors makes further development of this model important. Disturbance and water dynamics are two abiotic factors that have been shown to create stress gradients that can drive early ecosystem succession. The subsequent establishment of microbial communities and vegetation can then result in biogeomorphic feedbacks via ecosystem engineering that influence the role of disturbance and water dynamics within the system. Microbes can act as ecosystem engineers by supplying nutrients (via remineralization of organic matter and nitrogen fixation), enhancing soil development, either decreasing (encouraging weathering) or increasing (binding sediment grains) geomorphic stability, and helping retain soil moisture. Vegetation can act as an ecosystem engineer by fixing nitrogen, enhancing soil development, modifying microbial community structure, creating seed banks, and increasing geomorphic stability. The feedbacks between vegetation and water dynamics in glacial forefields are still poorly studied. We propose a synthesized model of ecosystem succession within glacial forefields that combines Matthews’ initial geoecological model and Corenblit's model to illustrate how gradients in environmental stress combined with successional time drive the balance between abiotic and biotic factors and ultimately determine the successional stage and potential for biogeomorphic feedbacks.

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