Demographic features and habitat preferences of southern pygmy mice (Baiomys musculus) in Colima, Mexico

2008 ◽  
Vol 86 (6) ◽  
pp. 507-524 ◽  
Author(s):  
Gary D. Schnell ◽  
Cassie J. Poindexter ◽  
Cornelio Sánchez-Hernández ◽  
María de Lourdes Romero-Almaraz ◽  
Michael L. Kennedy ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Small Mammals ◽  
Woody Plants ◽  
Environmental Variables ◽  
Dead Wood ◽  
Habitat Preferences ◽  
Ground Cover ◽  
Bare Ground ◽  
Open Canopy ◽  
Demographic Features

In Colima, Mexico, we conducted 8-night mark–recapture grid studies of southern pygmy mice ( Baiomys musculus (Merriam, 1892)) in January 2003–2007 in dry deciduous and tropical moist forests. For 40 000 trap-nights, 436 individuals were captured 764 times (comprising 18.6% of small mammals). The male:female ratio was 1:1.37, 82.9% were adults, 51.4% of females were pregnant or lactating, and coastal animals, on average, were heavier than those inland. Females moved farther than males. Baiomys was on 17 of 25 grids (densities 1.82–106.24 individuals/ha). Moon illumination did not affect capture or recapture probabilities, but trap-night did (overall, probability increased 1.66%/night). Grids with Baiomys had less bare ground and a more open canopy. Capture sites had more grass, less dead wood and bare ground, a more open and lower canopy, and greater distance to trees. Logistic regression indicated coastal capture sites had more forbs, grasses, and woody plants, and thicker vegetation at 1 m height with trees being relatively distant. Variables differed somewhat for northern sites, and the equation for all grids included 10 of 14 environmental variables. Baiomys frequented edge of an unimproved road traversing one grid. Baiomys musculus, widespread in Colima, exhibited preference for habitats with relatively dense ground cover and at least a partially open canopy.

scholarly journals Spatial and Temporal Changes in Habitat Heterogeneity Promote Partition of Resources of Small Mammals in a Midlatitude Temperate Forest

2018 ◽  
Author(s):  
Ivan M. De la Cruz-Arguello ◽  
Alondra Castro-Campillo ◽  
Alejandro Zavala-Hurtado ◽  
Arturo Salame-Méndez ◽  
José Ramírez-Pulido
Keyword(s):  
Small Mammals ◽  
Linear Models ◽  
Plant Cover ◽  
Habitat Preferences ◽  
Mixed Forest ◽  
Ground Cover ◽  
Dispersion Patterns ◽  
Microhabitat Heterogeneity ◽  
Close Relatives ◽  
Habitat Variables

AbstractOne of the basics and fundamentals problems in ecology is understand the factors that shape the spatial patterns in the distribution of the species and the coexistence of close relatives species. Among the most important factors governing the distributions and the coexistence of species are the spatiotemporal changes occurring in the microhabitat heterogeneity. Here, we assessed the heterogeneity of microhabitats and how they have an effect in the spatial segregation of two species of small mammals (i. e., Peromyscus difficilis and P. melanotis), which coexist in a temperate, mixed forest. We evaluated the microhabitat heterogeneity through multivariate statistics, using onto 23 habitat variables for vertical-horizontal habitat structure along pluvial seasons. To detect specific microdistribution changes and habitat preferences by two species of small mammals, we used second order spatial statistics and general linear models. According to their respective morphology and locomotive adaptations, the middle sized, midscansorial P. difficilis was resident all year long and preferred microhabitats with a high log ground cover, while the opportunistic, small sized, cursorial P. melanotis changed its occupancy area, depending on density of herbaceous and woody plants cover. Under the more benign microhabitat conditions of rainy season (denser plant coverage, milder temperature), both species showed closer microdistribution patterns; while these became repulsive at the less benign conditions of dry season (scarcer plant cover, colder temperature). Thus, we could confirm that seasonal changes of microhabitat heterogeneity promoted Peromyscus coexistence, through dispersion patterns reflecting partition of microhabitat resources.

scholarly journals Impacts of ski pistes preparation and ski tourism on vegetation

2018 ◽  
Vol 37 (2) ◽  
pp. 152-163
Author(s):  
Lýdia Kňazovičová ◽  
Silvia Chasníková ◽  
Ján Novák ◽  
Peter Barančok
Keyword(s):  
Species Composition ◽  
Impact Assessment ◽  
Environmental Variables ◽  
National Park ◽  
Ground Cover ◽  
Grassland Management ◽  
Nonnative Species ◽  
Bare Ground ◽  
Number Of Species ◽  
Human Interventions

AbstractVegetation of the ski slopes in the Low Tatras National Park in Slovakia was evaluated through the environmental variables and species composition caused by human impact assessment. We compared the grasslands located on pistes, off pistes and on the edge of pistes, and within these we also recorded the grassland management. The results show that the majority of study areas managed by transport of sod clippings has reached the lowest number of species; contrariwise, the grasslands with no management are characterized by the highest number of species. Areas on pistes managed by cutting correlates positively with the bare ground. Cover of mosses positively correlates with the total cover and areas with no management. Total of 17 synanthropic plant species and 2 nonnative species as the indicator of human interventions were noticed. They occurred particularly on the edge areas but also in the surroundings of the off piste areas.

scholarly journals Habitat Parameters and Small Mammal Associations of the Gaspe Shrew, Sorex gaspensis, in the Eastern Gaspé Peninsula, Québec

2008 ◽  
Vol 122 (2) ◽  
pp. 118 ◽  
Author(s):  
Christian Fortin ◽  
Denis Comeau
Keyword(s):  
Small Mammals ◽  
Small Mammal ◽  
Habitat Preferences ◽  
Ground Cover ◽  
Mammal Species ◽  
Running Water ◽  
Rocky Habitats ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula ◽  
Habitat Parameters

The Gaspé Shrew (Sorex gaspensis) is one of the rarest of Canadian small mammals. Consequently, little is known about its habitat preferences. This paper documents habitat parameters and small mammal species associated with the capture of nine specimens in the Gaspé Peninsula, Québec. Small mammals were collected using both pitfall traps and Victor snap traps at 22 sites during August and September 2005. A total of 571 small mammals representing 12 species was captured during 5637 trap nights. S. gaspensis specimens were trapped at sites located on hilly, rocky habitats. Microhabitat was cool and moist in all cases. Slope was always over 15 degrees and altitude ranged from 29 to 240 meters. Estimated percent of moss ground cover exceeded 50% in seven of the nine capture sites. Six S. gaspensis were trapped near running water while the others were captured far from streams. Overall, ten species of small mammals were captured in the same sites of S. gaspensis. Smoky Shrew (Sorex fumeus) was by far the most strongly associated species.

scholarly journals Characteristics and outcomes of children with dissociative (conversion) disorders in western China: a retrospective study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Zhixu Fang ◽  
Yuhang Li ◽  
Lingling Xie ◽  
Min Cheng ◽  
Jiannan Ma ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Environmental Variables ◽  
Binary Logistic Regression ◽  
Junior College ◽  
Conversion Disorder ◽  
Psychological Characteristics ◽  
Western China ◽  
Left Behind ◽  
Conversion Disorders ◽  
Close Relationship

Abstract Background Dissociative (conversion) disorder in children is a complex biopsychosocial disorder with high rates of medical and psychiatric comorbidities. We sought to identify the characteristics and outcomes of children with dissociative (conversion) disorders in western China. Methods We conducted a retrospective cohort study of 66 children admitted with dissociative (conversion) disorders from January 2017 to July 2019, and analyzed their clinical characteristics, socio-cultural environmental variables, and personality and psychiatric/psychological characteristics. Binary logistic regression was used to analyze the variables associated with clinical efficacy. Results Of these 66 patients, 38 (57.6%) were male and 28 (42.4%) were female, 46 (69.7%) had an antecedent stressor, 30 (45.5%) were left-behind adolescents, and 16 (24.2%) were from single-parent families. In addition, 30 patients (45.5%) were not close to their parents, 38 patients (59.4%) had an introverted personality, and 34 (53.1%) had unstable emotions. Thirteen families (19.7%) were uncooperative with the treatment. Patients who had cormorbid anxiety or depression exhibited significantly lower cognitive ability (P < 0.01). Logistic regression found that better treatment outcomes were positively associated with having a close relationship with parents, parental cooperation with treatment, and having a father with a lower level of education (i.e., less than junior college or higher). Conclusions The characteristics and outcomes of children with dissociative (conversion) disorders are related to socio-cultural environmental variables and psychiatric/psychological factors. Timely recognition and effective treatment of dissociative (conversion) disorders are important.

Effects of logging and fire on small mammals in Mumbulla State Forest, near Bega, New South Wales

1987 ◽  
Vol 14 (2) ◽  
pp. 163 ◽  
Author(s):  
D. Lunney ◽  
B. Cullis ◽  
P. Eby
Keyword(s):  
Small Mammals ◽  
New South ◽  
New South Wales ◽  
Canopy Cover ◽  
Ground Cover ◽  
First Year ◽  
Severe Effect ◽  
South Wales ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.

scholarly journals Urban inland wintertime N<sub>2</sub>O<sub>5</sub> and ClNO<sub>2</sub> influenced by snow-covered ground, air turbulence, and precipitation

2021 ◽  
Author(s):  
Kathryn D. Kulju ◽  
Stephen M. McNamara ◽  
Qianjie Chen ◽  
Jacinta Edebeli ◽  
Jose D. Fuentes ◽  
...  
Keyword(s):  
Ground Cover ◽  
Atmospheric Particulate Matter ◽  
Ionization Mass ◽  
Bare Ground ◽  
Near Surface ◽  
Dinitrogen Pentoxide ◽  
Nitryl Chloride ◽  
Air Turbulence ◽  
Chlorine Radicals ◽  
Wet Scavenging

Abstract. The atmospheric multiphase reaction of dinitrogen pentoxide (N2O5) with chloride-containing aerosol particles produces nitryl chloride (ClNO2), which has been observed across the globe. The photolysis of ClNO2 produces chlorine radicals and nitrogen dioxide (NO2), which alter pollutant fates and air quality. However, the effects of local meteorology on near-surface ClNO2 production are not yet well understood, as most observational and modeling studies focus on periods of clear conditions. During a field campaign in Kalamazoo, Michigan from January–February 2018, N2O5 and ClNO2 were measured using chemical ionization mass spectrometry, with simultaneous measurements of atmospheric particulate matter and meteorological parameters. We examine the impacts of atmospheric turbulence, precipitation (snow, rain) and fog, and ground cover (snow-covered and bare ground) on the abundances of ClNO2 and N2O5. N2O5 mole ratios were lowest during periods of lower turbulence and were not statistically significantly different between snow-covered and bare ground. In contrast, ClNO2 mole ratios were highest, on average, over snow-covered ground, due to saline snowpack ClNO2 production. Both N2O5 and ClNO2 mole ratios were lowest, on average, during rainfall and fog because of scavenging, with N2O5 scavenging by fog droplets likely contributing to observed increased particulate nitrate concentrations. These observations, specifically those during active precipitation and with snow-covered ground, highlight important processes, including N2O5 and ClNO2 wet scavenging, fog nitrate production, and snowpack ClNO2 production, that govern the variability in observed atmospheric chlorine and nitrogen chemistry and are missed when considering only clear conditions.

scholarly journals The Effects of Linguistic and Demographic Features of Chinese International Students on Placement Test Levels in Higher Education: Logistic Regression

2019 ◽  
Vol 9 (1) ◽  
pp. 225-241
Author(s):  
Eunjeong Park
Keyword(s):  
Higher Education ◽  
Logistic Regression ◽  
International Students ◽  
The United States ◽  
Chinese International Students ◽  
Placement Test ◽  
Placement Tests ◽  
High Stakes ◽  
College Type ◽  
Demographic Features

Higher education institutions in the United States provide placement essay tests to ensure international students’ readiness for college courses. The high-stakes nature of placement tests makes educators and researchers seek significant components of differentiating levels of placement tests. This study investigated the prediction of two levels (i.e., low vs. intermediate) of 411 placement test essays written by Chinese international students and examined the influence of linguistic and demographic features on placement test levels through logistic regression. The results show that the type-token ratio (TTR), tokens, college type, and graduate status were significant indicators to differentiate students’ placement test essays. However, several demographic features were not statistically significant. The results may shed light on improving writing skills of Chinese international students who scored intermediate or low in the placement tests.

scholarly journals Effects of cover crops on beetle assemblages in tea plantations

2021 ◽  
Author(s):  
Li-Lin Chen ◽  
Gabor Pozsgai ◽  
Xiang-Yu Li ◽  
Lei Li ◽  
Gadi V.P. Reddy ◽  
...  
Keyword(s):  
Species Richness ◽  
Pest Management ◽  
Cover Crops ◽  
Ground Cover ◽  
Paspalum Notatum ◽  
Bare Ground ◽  
Tea Plantations ◽  
Beetle Assemblages ◽  
Potential Benefits ◽  
Species Richness And Abundance

AbstractBeetles are visible members of food webs in tea plantations, with high species richness and abundance. Many tea pests, as well as natural enemies, are members of this order, so a knowledge of how groundcovers affect beetles can aid pest management. We collected beetles in a replicated field experiment in the Wuyi Mountains, Fujian Province China. Tea was intercropped with Paspalum notatum or Chamaecrista rotundifolia, or rows were cleared to bare ground, or in the control they were left unmanaged to allow weeds to grow naturally. Sampling, done by sweep netting and vegetation beating, was conducted monthly, between May 2006 and April 2008, and Coleoptera abundance, biomass, species richness and assemblage structures were compared between groundcover treatments. Total beetle abundance and species richness were significantly higher in tea intercropped with C. rotundifolia and bare ground than in naturally grown weedy control. Whilst there was no difference between predator assemblages among treatments for any measure, herbivores were more abundant, weighed more, and were more diverse in C. rotundifolia treatments than in weedy control. Biomass and species richness were also greater in plots with P. notatum groundcover than those in weedy control. We found that beetle assemblages varied both seasonally and with ground cover treatment, but the potential pest control impact of more species-rich beetle assemblages was mixed, and further work is needed to gain information on trophic groups with potential benefits for use in non-insecticidal pest management.

Surfacing behaviour and ecology of the marsupial mole (Notoryctes typhlops) at Uluru-Kata Tjuta National Park

2014 ◽  
Vol 36 (2) ◽  
pp. 184 ◽  
Author(s):  
Kerrie Bennison ◽  
Jim Clayton ◽  
Robert Godfree ◽  
Chris Pavey ◽  
Melinda Wilson
Keyword(s):  
Environmental Variables ◽  
National Park ◽  
Survey Methods ◽  
Habitat Preferences ◽  
Rainfall Events ◽  
Significant Relationships ◽  
Cumulative Rainfall ◽  
Sign Surveys ◽  
Distribution And Ecology ◽  
Over Time

Little is known about the distribution and ecology of the cryptic and unique marsupial mole. In this paper we report on the habitat preferences and surfacing behaviour of marsupial moles on the basis of surface sign surveys conducted in Uluru-Kata Tjuta National Park and Ayers Rock Resort over a 12-month period by Uluru-Kata Tjuta National Park staff and traditional owners. A key aim of the study was to assess the potential viability of using surface sign as a rapid, non-intrusive alternative to traditional survey methods. We found that surfacing occurred widely across the study area, but that it was highly variable both across survey sites and over time. Significant relationships existed between surface sign counts and environmental variables, including fire age, timing of significant rainfall events, presence of infrastructure and the cumulative rainfall received in the preceding three months. We concluded that the use of marsupial mole surface sign is likely to be a useful method for monitoring the distribution, abundance and habitat requirements of this cryptic species.

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