Soil movement by burrowing mammals

2016 ◽  
Vol 41 (1) ◽  
pp. 29-45 ◽  
Author(s):  
Natalie S Haussmann
Keyword(s):  
Body Size ◽  
Spatial Scales ◽  
Group Living ◽  
Point Of View ◽  
Volume Estimation ◽  
Mammal Species ◽  
Soil Movement ◽  
Habitat Creation ◽  
Sediment Removal ◽  
Volume Estimates

Mammal burrowing plays an important role in soil translocation and habitat creation in many environments. As a consequence, many burrowing mammals have at some point been studied in an ecosystem engineering context. From a geomorphological point of view, one of the focus areas of burrowing mammal research is on the amount of soil that is excavated and the rate at which this happens. As such, reviews exist on the volumes and rates of sediment removal by burrowing mammals in specific environments or for specific groups of species. Here, a standardised comparison of mammal burrowing across a broad range of burrowing mammal species and environments is provided, focussing on both burrow volume and excavation rate. Through an ISI Web of Science-based literature search, articles presenting estimates of burrow volumes and/or excavation rate were identified. Relationships between species body size and burrow volume/excavation rate were explored and the influence of sociality and method of burrow volume estimation were assessed. The results show that, although larger species construct larger burrows, it is the smaller species that remove more sediment per unit time at larger, site-level spatial scales. Burrow volume estimates are, however, independent of species sociality (solitary versus group-living) and method of burrow volume estimation (excavation-based versus mound-based). These results not only confirm previously established relationships between species body size and burrow volume, but, more importantly, they also add to this, by exploring larger scale impacts of burrowing mammals along a body size gradient.

scholarly journals Future large hydropower dams impact global freshwater megafauna

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Christiane Zarfl ◽  
Jürgen Berlekamp ◽  
Fengzhi He ◽  
Sonja C. Jähnig ◽  
William Darwall ◽  
...  
Keyword(s):  
Spatial Scales ◽  
Point Of View ◽  
Ecological Impacts ◽  
Climate Mitigation ◽  
Threat Status ◽  
Hydropower Dams ◽  
Balkan Region ◽  
America South ◽  
Freshwater Management ◽  
Major Attention

AbstractDam construction comes with severe social, economic and ecological impacts. From an ecological point of view, habitat types are altered and biodiversity is lost. Thus, to identify areas that deserve major attention for conservation, existing and planned locations for (hydropower) dams were overlapped, at global extent, with the contemporary distribution of freshwater megafauna species with consideration of their respective threat status. Hydropower development will disproportionately impact areas of high freshwater megafauna richness in South America, South and East Asia, and the Balkan region. Sub-catchments with a high share of threatened species are considered to be most vulnerable; these are located in Central America, Southeast Asia and in the regions of the Black and Caspian Sea. Based on this approach, planned dam locations are classified according to their potential impact on freshwater megafauna species at different spatial scales, attention to potential conflicts between climate mitigation and biodiversity conservation are highlighted, and priorities for freshwater management are recommended.

scholarly journals A Farewell to the Encephalization Quotient: A New Brain Size Measure for Comparative Primate Cognition

2021 ◽  
pp. 1-12
Author(s):  
Carel P. van Schaik ◽  
Zegni Triki ◽  
Redouan Bshary ◽  
Sandra A. Heldstab
Keyword(s):  
Body Size ◽  
Cognitive Abilities ◽  
Brain Size ◽  
Estimation Error ◽  
Primate Species ◽  
Mammal Species ◽  
Mean Values ◽  
Encephalization Quotient ◽  
Body Sizes ◽  
Size Measure

Both absolute and relative brain sizes vary greatly among and within the major vertebrate lineages. Scientists have long debated how larger brains in primates and hominins translate into greater cognitive performance, and in particular how to control for the relationship between the noncognitive functions of the brain and body size. One solution to this problem is to establish the slope of cognitive equivalence, i.e., the line connecting organisms with an identical bauplan but different body sizes. The original approach to estimate this slope through intraspecific regressions was abandoned after it became clear that it generated slopes that were too low by an unknown margin due to estimation error. Here, we revisit this method. We control for the error problem by focusing on highly dimorphic primate species with large sample sizes and fitting a line through the mean values for adult females and males. We obtain the best estimate for the slope of circa 0.27, a value much lower than those constructed using all mammal species and close to the value expected based on the genetic correlation between brain size and body size. We also find that the estimate of cognitive brain size based on cognitive equivalence fits empirical cognitive studies better than the encephalization quotient, which should therefore be avoided in future studies on primates and presumably mammals and birds in general. The use of residuals from the line of cognitive equivalence may change conclusions concerning the cognitive abilities of extant and extinct primate species, including hominins.

scholarly journals Body size, reef area and temperature predict global reef-fish species richness across spatial scales

2018 ◽  
Vol 28 (3) ◽  
pp. 315-327 ◽  
Author(s):  
D. R. Barneche ◽  
E. L. Rezende ◽  
V. Parravicini ◽  
E. Maire ◽  
G. J. Edgar ◽  
...  
Keyword(s):  
Species Richness ◽  
Body Size ◽  
Reef Fish ◽  
Fish Species ◽  
Spatial Scales ◽  
Reef Area ◽  
Reef Fish Species

scholarly journals A Comprehensive Review of Low Impact Development Models for Research, Conceptual, Preliminary and Detailed Design Applications

Water ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1541 ◽  
Author(s):  
Sahereh Kaykhosravi ◽  
Usman Khan ◽  
Amaneh Jadidi
Keyword(s):  
Spatial Data ◽  
Spatial Scales ◽  
Low Impact Development ◽  
Model Development ◽  
Point Of View ◽  
Tree Canopy ◽  
Balance Model ◽  
Runoff Generation ◽  
Development Models ◽  
Model Features

This review compares and evaluates eleven Low Impact Development (LID) models on the basis of: (i) general model features including the model application, the temporal resolution, the spatial data visualization, the method of placing LID within catchments; (ii) hydrological modelling aspects including: the type of inbuilt LIDs, water balance model, runoff generation and infiltration; and (iii) hydraulic modelling methods with a focus on the flow routing method. Results show that despite the recent updates of existing LID models, several important features are still missing and need improvement. These features include the ability to model: multi-layer subsurface media, tree canopy and processes associated with vegetation, different spatial scales, snowmelt and runoff calculations. This review provides in-depth insight into existing LID models from a hydrological and hydraulic point of view, which will facilitate in selecting the best-suited model. Recommendations on further studies and LID model development are also presented.

scholarly journals Habitat and social factors shape individual decisions and emergent group structure during baboon collective movement

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Ariana Strandburg-Peshkin ◽  
Damien R Farine ◽  
Margaret C Crofoot ◽  
Iain D Couzin
Keyword(s):  
Group Structure ◽  
Spatial Scales ◽  
Group Living ◽  
Habitat Features ◽  
3 Dimensional ◽  
Collective Movement ◽  
Dimensional Reconstruction ◽  
Individual Decisions ◽  
Emergent Structure ◽  
Road Following

For group-living animals traveling through heterogeneous landscapes, collective movement can be influenced by both habitat structure and social interactions. Yet research in collective behavior has largely neglected habitat influences on movement. Here we integrate simultaneous, high-resolution, tracking of wild baboons within a troop with a 3-dimensional reconstruction of their habitat to identify key drivers of baboon movement. A previously unexplored social influence – baboons’ preference for locations that other troop members have recently traversed – is the most important predictor of individual movement decisions. Habitat is shown to influence movement over multiple spatial scales, from long-range attraction and repulsion from the troop’s sleeping site, to relatively local influences including road-following and a short-range avoidance of dense vegetation. Scaling to the collective level reveals a clear association between habitat features and the emergent structure of the group, highlighting the importance of habitat heterogeneity in shaping group coordination.

scholarly journals Cooperative Behaviors in Group-Living Spider Mites

2021 ◽  
Vol 9 ◽  
Author(s):  
Peter Schausberger ◽  
Shuichi Yano ◽  
Yukie Sato
Keyword(s):  
Spatial Scales ◽  
Group Living ◽  
Spider Mites ◽  
Species Group ◽  
Future Research ◽  
Plant Colonization ◽  
Individual Host ◽  
Indirect Fitness ◽  
Cooperative Behaviors ◽  
Indirect Cues

Cooperative behaviors are evolutionary stable if the direct and/or indirect fitness benefits exceed the costs of helping. Here we discuss cooperation and behaviors akin to cooperation in subsocial group-living species of two genera of herbivorous spider mites (Tetranychidae), i.e., the largely polyphagous Tetranychus spp. and the nest-building Stigmaeopsis spp., which are specialized on grasses, such as bamboo. These spider mites are distributed in patches on various spatial scales, that is, within and among leaves of individual host plants and among individual hosts of single or multiple plant species. Group-living of spider mites is brought about by plant-colonizing foundresses ovipositing at local feeding sites and natal site fidelity, and by multiple individuals aggregating in the same site in response to direct and/or indirect cues, many of which are associated with webbing. In the case of the former, emerging patches are often composed of genetically closely related individuals, while in the case of the latter, local patches may consist of kin of various degrees and/or non-kin and even heterospecific spider mites. We describe and discuss ultimate and proximate aspects of cooperation by spider mites in host plant colonization and exploitation, dispersal, anti-predator behavior, and nesting-associated behaviors and conclude with theoretical and practical considerations of future research on cooperation in these highly rewarding model animals.

scholarly journals Application of a revised Water Poverty Index to target the water poor

2011 ◽  
Vol 63 (6) ◽  
pp. 1099-1110 ◽  
Author(s):  
R. Giné Garriga ◽  
A. Pérez Foguet
Keyword(s):  
Water Resources ◽  
Policy Making ◽  
Spatial Scales ◽  
Point Of View ◽  
Poverty Index ◽  
Index Construction ◽  
Policy Tool ◽  
Water Poverty Index ◽  
Decision Making Processes

The Water Poverty Index (WPI) has been recognized as a useful tool in policy analysis. The index integrates various physical, social and environmental aspects to enable more holistic assessment of water resources. However, soundness of this tool relies on two complementary aspects: (i) inadequate techniques employed in index construction would produce unreliable results, and (ii) poor dissemination of final outcome would reduce applicability of the index to influence policy-making. From a methodological point of view, a revised alternative to calculate the index was developed in a previous study. This paper is therefore concerned not with the method employed in index construction, but with how the composite can be applied to support decision-making processes. In particular, the paper examines different approaches to exploit the index as a policy tool. A number of alternatives to disseminate achieved results are presented. The implications of applying the composite at different spatial scales are highlighted. Turkana District, in Kenya has been selected as initial case study to test the applicability and validity of the index. The paper concludes that the WPI approach provides a relevant tool for guiding appropriate action and policy-making towards more equitable allocation of water resources.

Thermal-Mechanical Effects and Near-Critical Fluid Dynamic Behaviors in Micro-Scale

2021 ◽  
pp. 55-111
Author(s):  
Lin Chen
Keyword(s):  
Fluid Dynamic ◽  
Spatial Scales ◽  
Small Time ◽  
Point Of View ◽  
Dynamic Responses ◽  
Chemical Extraction ◽  
Scaling Effects ◽  
Mechanical Process ◽  
Micro Scale ◽  
Leading Role

Supercritical CO2 fluid has been widely used in chemical extraction, chemical synthesis, micro-manufacturing, and heat transfer apparatus, and so forth. The current chapter deals with near-critical CO2 micro-scale thermal convective flow and the effects of thermal-mechanical process. When the scale becomes smaller, new, and detailed figures of near-critical thermal effects emerges. To explore this new area, theoretical developments and numerical investigations are discussed and explained in this chapter. From a theoretical point of view, the thermal-mechanical nature of near-critical fluid would play a leading role in small time and spatial scales. This effect is found dominant to the thermal dynamic responses and convective structures of micro-scale fluid behaviors. The scaling effects, boundary thermal-mechanical process, instability evolutions, mixing flows and characteristics, possible extensions, and applications are also discussed in this chapter.

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