Display dispersion and micro-habitat use by the Malaysian peacock pheasant Polyplectron malacense in Peninsular Malaysia

1994 ◽  
Vol 10 (2) ◽  
pp. 229-244 ◽  
Author(s):  
Philip J. K. McGowan

ABSTRACTThe spatial distribution of displaying Malaysian peacock pheasants was documented at a site in Peninsular Malaysia. Calling males were clustered and, therefore, were not evenly distributed throughout the available habitat. The location of these clusters differed between calling periods. An objective method of assessing micro-habitat structure at the forest-floor level was devised to investigate habitat use by displaying males. Habitat structure was measured at 197 points throughout the study site, both in areas used by the pheasant and in those areas not used by the pheasant. A DECORANA ordination revealed that two gradients explained much of the variation in micro-habitat structure. Male calling clusters were located in areas that were away from the river and more stable (e.g. fewer treefalls). Within these clusters, display scrapes were sited in areas that were more stable and were more influenced by the rivers than elsewhere within the area used by the calling males. It is suggested that the environmental gradients described by the ordination are more likely to determine the position of the calling cluster than individual habitat structure variables. Within calling clusters, however, it seems probable that the presence or absence of ground-level vegetation directly influences the siting of display scrapes.

2006 ◽  
Vol 33 (2) ◽  
pp. 137 ◽  
Author(s):  
Grainne S. Maguire

Fine-scale variation in habitat structure and composition is likely to influence habitat use by avian species with limited flight capabilities. I investigated proportional use of available habitat and microhabitat by the southern emu-wren (Stipiturus malachurus), a threatened, flight-limited passerine, at three sites in Victoria, in relation to vegetation structure and composition. Emu-wrens appeared to discriminate between habitats with regard to structural rather than floristic characteristics. Habitats with dense vertical foliage of shrubs, grasses and sedges/rushes between ground level and 100 cm, and dense horizontal cover of medium to tall shrubs, were used most frequently. However, when availability of habitat was taken into account, habitat use was negatively correlated with the vertical density of low shrub foliage and species richness. Within habitats, emu-wrens more frequently used plant species that had a dense canopy cover (26 ± 2% of total cover, crown diameter 93 ± 5 cm), high foliage density between 50 and 100 cm, and average heights of ~1 m. Plant species in which the birds nested comprised ~14% of total canopy cover and were densest between ground level and 50 cm. Canopy cover, vegetation height and vertical foliage density were consistently important variables correlated with emu-wren habitat use at multiple fine-scales. This study provides valuable information for conservation management of the species; in particular, the restoration of degraded habitats.


Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 62
Author(s):  
Robert Cichowicz ◽  
Maciej Dobrzański

Spatial analysis of the distribution of particulate matter PM10, PM2.5, PM1.0, and hydrogen sulfide (H2S) gas pollution was performed in the area around a university library building. The reasons for the subject matter were reports related to the perceptible odor characteristic of hydrogen sulfide and a general poor assessment of air quality by employees and students. Due to the area of analysis, it was decided to perform measurements at two heights, 10 m and 20 m above ground level, using measuring equipment attached to a DJI Matrice 600 unmanned aerial vehicle (UAV). The aim of the measurements was air quality assessment and investigate the convergence of the theory of air flow around the building with the spatial distribution of air pollutants. Considerable differences of up to 63% were observed in the concentrations of pollutants measured around the building, especially between opposite sides, depending on the direction of the wind. To explain these differences, the theory of aerodynamics was applied to visualize the probable airflow in the direction of the wind. A strong convergence was observed between the aerodynamic model and the spatial distribution of pollutants. This was evidenced by the high concentrations of dust in the areas of strong turbulence at the edges of the building and on the leeward side. The accumulation of pollutants was also clearly noticeable in these locations. A high concentration of H2S was recorded around the library building on the side of the car park. On the other hand, the air turbulence around the building dispersed the gas pollution, causing the concentration of H2S to drop on the leeward side. It was confirmed that in some analyzed areas the permissible concentration of H2S was exceeded.


2015 ◽  
Vol 37 (4) ◽  
pp. 439 ◽  
Author(s):  
Débora Reis de Carvalho ◽  
Ruanny Casarim ◽  
Rafaela Bastos Pereira ◽  
Paulo Santos Pompeu

2015 ◽  
Vol 813-814 ◽  
pp. 1126-1130
Author(s):  
G. Kesavan ◽  
S.S. Chandrasekaran

The maximum load carrying capacity of bored piles is a complex problem because it is a function of a number of factors, these factors include methods of soil exploration, ground water condition, types of grading of concrete, quantity and quality of concrete. The knowledge of Geotechnical test is important for the most economical design of the piles. This paper describes some important aspects of field investigation, design and construction of in-situ bored pile foundation, field pile load test of experience gained from the construction of the pile at a site in Aathoor in Tamil Nadu, India. The site was fully sandy soil from existing ground level. The design of bored pile under axial compression was done using Empirical formula, pile load test and by using PLAXIS 2D software. Results were compared with vertical load and settlement in this site.


2021 ◽  
Author(s):  
Pengwei Qiao ◽  
Donglin Lai ◽  
Sucai Yang ◽  
Qianyun Zhao ◽  
Hengqin Wang

Abstract The prediction accuracy of the spatial distribution of soil pollutants at a site is relatively low. Related pollutants can be used as auxiliary variables to improve the prediction accuracy. However, little relevant research has been conducted on site soil pollution. To analyze the prediction accuracy of target pollutants combined with auxiliary pollutants, Cu, toluene, and phenanthrene were selected as the target pollutants for this study. Based on geostatistical analysis and spatial analysis, the following results were obtained. (1) The reduction rate of the root mean square errors (RMSEs) for Cu, toluene, and phenanthrene with multivariable cokriging were 68.4%, 81.6%, and 81.2%, respectively, which are proportional to the correlation coefficient of the relationship between the auxiliary pollutants and the target pollutants. (2) The predicted results for Cu, phenanthrene, and toluene and their corresponding related pollutants are more accurate than the results obtained not using the related pollutants. (3) In the interpolation process, the RMSEs for Cu, toluene, and phenanthrene with multivariable cokriging basically increase as the neighborhood sample data increases, and then they become stable. (4) When 84, 61, and 34 sample points were removed, the RMSEs for Cu, toluene, and phenanthrene, respectively with multivariable cokriging were close to the RMSEs of the target pollutants based on the total samples. The results are of great significance to improving the prediction accuracy of the spatial distribution of soil pollutants at coking plant sites.


2019 ◽  
Vol 26 (4) ◽  
pp. 655-670 ◽  
Author(s):  
Najeebullah Khan ◽  
Sahar Hadi Pour ◽  
Shamsuddin Shahid ◽  
Tarmizi Ismail ◽  
Kamal Ahmed ◽  
...  

2003 ◽  
Vol 30 (6) ◽  
pp. 565 ◽  
Author(s):  
A. D. Arthur ◽  
R. P. Pech ◽  
A. Drew ◽  
E. Gifford ◽  
S. Henry ◽  
...  

We investigated experimentally the influence of habitat structure on the population dynamics of house mice. Three habitat types were used. In one, dense stands of regenerating cypress pine were felled and left in situ to cover at least 40% of experimental plots, providing high complexity at ground level; in another, dense stands of regenerating pine were left intact, providing low complexity at ground level; in the third, open grassland adjacent to dense stands of regenerating pine also provided low complexity at ground level. Mouse populations occurred at higher densities in felled pine plots compared with both the standing pine and grassland plots, consistent with the hypothesis that the presence of increased habitat complexity at ground level reduced the impact of predation. Even though populations responded to the felled pine, they dropped to very low densities over winter, suggesting that the habitat was still marginal for the persistence of mice, probably due to a lack of food. The results are discussed with reference to their implications for the influence that habitat structure may have on the impact of introduced predators on native species.


1998 ◽  
Vol 8 (4) ◽  
pp. 241 ◽  
Author(s):  
RJ Ansley ◽  
DL Jones ◽  
TR Tunnell ◽  
BA Kramp ◽  
PW Jacoby

Honey mesquite (Prosopis glandulosa Torr.) canopy responses to fire were measured following 20 single winter fires conducted in north Texas. Weather conditions during the fires, understory herbaceous fine fuel (fine fuel) amount and moisture content, fire temperature at 0 cm, 10-30 cm and 1-3 m above ground, and canopy responses were compared. Ten fires occurred on a site where fine fuel was a mixture of cool and warm season grasses (mixed site). The other 10 fires occurred on a site dominated by warm season grasses (warm site). When both sites were included in regressions, peak fire temperature at all heights was positively related to fine fuel amount. Fine fuel amount, fine fuel moisture content, air temperature (AT) and relative humidity (RH) affected fire temperature duration in seconds over 100°C (FTD100) at 1-3 m height, but not at ground level. Mesquite percent above-ground mortality (topkill) increased with increasing fine fuel amount, decreasing fuel moisture content, increasing AT, and decreasing RH. Percent foliage remaining on non-topkilled (NTK) trees was inversely related to fine fuel amount and AT, and positively related to fine fuel moisture content. Effect of fire on mesquite topkill and foliage remaining of NTK trees was strongly affected by RH at the warm site (r2 = 0.92 and 0.82, respectively), but not at the mixed site. This difference was due to RH affecting fuel moisture content (and subsequently fire behavior) to a greater degree at the warm than at the mixed site, because of the lower green tissue content in warm site grasses at the time of burning. Under adequate fine fuel amounts to carry a fire, mesquite canopy responses to fire (i.e., topkill vs, partial canopy defoliation) were largely determined by AT and RH conditions during the fire. This has implications if the management goal is to preserve the mesquite overstory for a savanna result instead of topkilling all trees. Two substudies were conducted during 3 of the fires. Substudy 1 determined mesquite response to fire in 2 plots with different understory herbaceous fuel loads (5,759 vs. 2,547 kg/ha) that were burned under under similar weather conditions. Mesquite topkill was 81% and 11% in the high and low fuel fires, respectively. Under similar weather conditions, fine fuel was an important factor in affecting mesquite responses to fire. However, as demonstrated in the main study, under a variety of weather conditions, AT and RH influenced mesquite response to fire as much or more than did fine fuel. Substudy 2 compared response of mesquite plants with abundant and dry subcanopy fine fuel (3252 kg/ha; fuel moisture 10.4%), or sparse and green subcanopy fuel (1155 kg/ha; fuel moisture 25.9%) to a high intensity fire. All trees were topkilled, including those with low subcanopy fuel, probably from convection heat generated from herbaceous fuel in interspaces between trees. In support of this conclusion, thermocouple data from all 20 fires indicated that canopy responses were more related to fire temperature at 1-3 m than at lower heights. This suggests that the topkill mechanism was due to convective heat within the canopy rather than a girdling effect of fire at stem bases.


2013 ◽  
Author(s):  
Stephanie A. Moore ◽  
Guillaume Dramais ◽  
Philippe Dussouillez ◽  
Jéro^me Le Coz ◽  
Colin Rennie ◽  
...  

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