scholarly journals A dynamic multi‐scale occupancy model to estimate temporal dynamics and hierarchical habitat use for nomadic species

2019 ◽  
Vol 9 (2) ◽  
pp. 793-803 ◽  
Author(s):  
Adam W. Green ◽  
David C. Pavlacky ◽  
T. Luke George
Keyword(s):  
Habitat Use ◽  
Temporal Dynamics ◽  
Occupancy Model ◽  
Multi Scale

scholarly journals Multi-Scale Ionospheric Anomalies Monitoring and Spatio-Temporal Analysis during Intense Storm

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 215
Author(s):  
Na Cheng ◽  
Shuli Song ◽  
Wei Li
Keyword(s):  
Magnetic Storm ◽  
Large Scale ◽  
Temporal Dynamics ◽  
Ionospheric Disturbance ◽  
Ionospheric Scintillation ◽  
Small Scale ◽  
Electron Content ◽  
Total Electron ◽  
Multi Scale ◽  
Intense Storm

The ionosphere is a significant component of the geospace environment. Storm-induced ionospheric anomalies severely affect the performance of Global Navigation Satellite System (GNSS) Positioning, Navigation, and Timing (PNT) and human space activities, e.g., the Earth observation, deep space exploration, and space weather monitoring and prediction. In this study, we present and discuss the multi-scale ionospheric anomalies monitoring over China using the GNSS observations from the Crustal Movement Observation Network of China (CMONOC) during the 2015 St. Patrick’s Day storm. Total Electron Content (TEC), Ionospheric Electron Density (IED), and the ionospheric disturbance index are used to monitor the storm-induced ionospheric anomalies. This study finally reveals the occurrence of the large-scale ionospheric storms and small-scale ionospheric scintillation during the storm. The results show that this magnetic storm was accompanied by a positive phase and a negative phase ionospheric storm. At the beginning of the main phase of the magnetic storm, both TEC and IED were significantly enhanced. There was long-duration depletion in the topside ionospheric TEC during the recovery phase of the storm. This study also reveals the response and variations in regional ionosphere scintillation. The Rate of the TEC Index (ROTI) was exploited to investigate the ionospheric scintillation and compared with the temporal dynamics of vertical TEC. The analysis of the ROTI proved these storm-induced TEC depletions, which suppressed the occurrence of the ionospheric scintillation. To improve the spatial resolution for ionospheric anomalies monitoring, the regional Three-Dimensional (3D) ionospheric model is reconstructed by the Computerized Ionospheric Tomography (CIT) technique. The spatial-temporal dynamics of ionospheric anomalies during the severe geomagnetic storm was reflected in detail. The IED varied with latitude and altitude dramatically; the maximum IED decreased, and the area where IEDs were maximum moved southward.

scholarly journals Multi-scale habitat use analysis and interspecific Ecology of the Critically Endangered Black-breasted Puffleg Eriocnemis nigrivestis

2015 ◽  
Vol 25 (4) ◽  
pp. 479-488 ◽  
Author(s):  
ESTEBAN A. GUEVARA ◽  
ELISA BONACCORSO ◽  
JOOST F. DUIVENVOORDEN
Keyword(s):  
Habitat Use ◽  
Habitat Degradation ◽  
Physiological Stress ◽  
Selection Process ◽  
Habitat Model ◽  
Critically Endangered ◽  
Use Patterns ◽  
Multi Scale ◽  
The North ◽  
Competition Hypothesis

SummaryThe Black-breasted Puffleg Eriocnemis nigrivestis is a hummingbird endemic to Ecuador and considered Critically Endangered, given its limited distribution, low population numbers, and ongoing habitat degradation. We investigated habitat use patterns using landscape and microhabitat variables. In addition, we explored a previously postulated competition hypothesis involving the Black-breasted Puffleg and the Gorgeted Sunangel Heliangelus strophianus. Our results suggest that landscape variables may play a role in the habitat selection process; specifically the distance to nearest forest border seems to have a significant effect on our habitat model. We speculate that, as the species is known to perform seasonal movements, the avoidance of forest border might reduce the physiological stress caused by altitudinal migration. At microhabitat level, Black-breasted Puffleg seems not sensitive to forest structure variables. Our findings suggest that ensuring forest tract connectivity, between the altitudinal extremes of the species’ range at the north-western flanks of the Pichincha volcano, might be crucial for survival of the species during its annual cycle. However, non-metric multidimensional scaling (NMDS) indicates that Black-breasted Puffleg and the Gorgeted Sunangel do not overlap spatially, but this finding is not conclusive considering our field observations.

scholarly journals A multi-scale eco-evolutionary model of cooperation reveals how microbial adaptation influences soil decomposition

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Elsa Abs ◽  
Hélène Leman ◽  
Régis Ferrière
Keyword(s):  
Temporal Dynamics ◽  
Global Environmental Change ◽  
Evolutionary Model ◽  
Terrestrial Ecosystems ◽  
Microbial Decomposition ◽  
Multi Scale ◽  
Spatio Temporal ◽  
The Stability ◽  
Micro Organisms ◽  
Som Decomposition

AbstractThe decomposition of soil organic matter (SOM) is a critical process in global terrestrial ecosystems. SOM decomposition is driven by micro-organisms that cooperate by secreting costly extracellular (exo-)enzymes. This raises a fundamental puzzle: the stability of microbial decomposition in spite of its evolutionary vulnerability to “cheaters”—mutant strains that reap the benefits of cooperation while paying a lower cost. Resolving this puzzle requires a multi-scale eco-evolutionary model that captures the spatio-temporal dynamics of molecule-molecule, molecule-cell, and cell-cell interactions. The analysis of such a model reveals local extinctions, microbial dispersal, and limited soil diffusivity as key factors of the evolutionary stability of microbial decomposition. At the scale of whole-ecosystem function, soil diffusivity influences the evolution of exo-enzyme production, which feeds back to the average SOM decomposition rate and stock. Microbial adaptive evolution may thus be an important factor in the response of soil carbon fluxes to global environmental change.

scholarly journals Multi-scale analysis to uncover habitat use of red-crowned cranes: Implications for conservation

2013 ◽  
Vol 59 (5) ◽  
pp. 604-617 ◽  
Author(s):  
Chunyue Liu ◽  
Hongxing Jiang ◽  
Shuqing Zhang ◽  
Chunrong Li ◽  
Yunqiu Hou ◽  
...  
Keyword(s):  
Habitat Use ◽  
Positive Impact ◽  
Spatial Scales ◽  
Paddy Fields ◽  
Natural Habitats ◽  
Multi Scale ◽  
Aquaculture Ponds ◽  
Natural Wetlands ◽  
Percent Area ◽  
Area Percentage

Abstract A multi-scale approach is essential to assess the factors that limit avian habitat use. Numerous studies have examined habitat use by the red-crowned crane, but integrated multi-scale habitat use information is lacking. We evaluated the effects of several habitat variables quantified across many spatial scales on crane use and abundance in two periods (2000 and 2009) at Yancheng National Nature Reserve, China. The natural wetlands decreased in area by 30,601 ha (-6.9%) from 2000 to 2009, predominantly as a result of conversion to aquaculture ponds and farmland, and the remaining was under degradation due to expansion of the exotic smooth cordgrass. The cranes are focusing in on either larger patches or those that are in close proximity to each other in both years, but occupied patches had smaller size, less proximity and more regular boundaries in 2009. At landscape scales, the area percentage of common seepweed, reed ponds and paddy fields had a greater positive impact on crane presence than the area percentage of aquaculture ponds. The cranes were more abundant in patches that had a greater percent area of common seepweed and reed ponds, while the percent area of paddy fields was inversely related to crane abundance in 2009 due to changing agricultural practices. In 2009, cranes tended to use less fragmented plots in natural wetlands and more fragmented plots in anthropogenic paddy fields, which were largely associated with the huge loss and degradation of natural habitats between the two years. Management should focus on restoration of large patches of natural wetlands, and formation of a relatively stable area of large paddy field and reed pond to mitigate the loss of natural wetlands.

scholarly journals A dynamic occupancy model for interacting species with two spatial scales

2020 ◽  
Author(s):  
Eivind Flittie Kleiven ◽  
Frederic Barraquand ◽  
Olivier Gimenez ◽  
John-André Henden ◽  
Rolf Anker Ims ◽  
...  
Keyword(s):  
Spatial Structure ◽  
Species Interactions ◽  
Spatial Scales ◽  
Species Interaction ◽  
Camera Traps ◽  
Occupancy Models ◽  
Occupancy Model ◽  
Interacting Species ◽  
Multi Scale ◽  
Extinction Probabilities

1AbstractOccupancy models have been developed independently to account for multiple spatial scales and species interactions in a dynamic setting. However, as interacting species (e.g., predators and prey) often operate at different spatial scales, including nested spatial structure might be especially relevant in models of interacting species. Here we bridge these two model frameworks by developing a multi-scale two-species occupancy model. The model is dynamic, i.e. it estimates initial occupancy, colonization and extinction probabilities - including probabilities conditional to the other species’ presence. With a simulation study, we demonstrate that the model is able to estimate parameters without bias under low, medium and high average occupancy probabilities, as well as low, medium and high detection probabilities. We further show the model’s ability to deal with sparse field data by applying it to a multi-scale camera trapping dataset on a mustelid-rodent predator-prey system. The field study illustrates that the model allows estimation of species interaction effects on colonization and extinction probabilities at two spatial scales. This creates opportunities to explicitly account for the spatial structure found in many spatially nested study designs, and to study interacting species that have contrasted movement ranges with camera traps.

scholarly journals Multi-scale path-level analysis of jaguar habitat use in the Pantanal ecosystem

2021 ◽  
Vol 253 ◽  
pp. 108900
Author(s):  
Guilherme Costa Alvarenga ◽  
Luca Chiaverini ◽  
Samuel A. Cushman ◽  
Egil Dröge ◽  
David W. Macdonald ◽  
...  
Keyword(s):  
Habitat Use ◽  
Multi Scale ◽  
Level Analysis

Multi-Scale Analyses of Habitat Use by Elk Following Wildfire

2010 ◽  
Vol 84 (1) ◽  
pp. 20-32 ◽  
Author(s):  
James R. Biggs ◽  
Dawn M. VanLeeuwen ◽  
Jerry L. Holechek ◽  
Raul Valdez
Keyword(s):  
Habitat Use ◽  
Multi Scale
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