scholarly journals Does the use of playback affect the estimated numbers of red–legged partridge Alectoris rufa?

2012 ◽  
Vol 35 (2) ◽  
pp. 429-435
Author(s):  
P. Tizzani ◽  
◽  
E. Negri ◽  
F. Silvano ◽  
G. Malacarne ◽  
...  
Keyword(s):  
Critical Evaluation ◽  
Alectoris Rufa ◽  
Size Estimation ◽  
Monitoring Methods ◽  
Direct Observations ◽  
Underestimation Rate ◽  
Conservation Threats ◽  
Changes Over Time ◽  
Monitoring Area

The red–legged partridge Alectoris rufa lives in a situation of potential conservation risk for its long–term preservation in Italy as its habitat is increasingly threatened by the disappearance of traditional agriculture–related environments. In such a situation, it is important to use effective and appropriate monitoring methods to assess population changes over time and to identify potential conservation threats. The objective of this study was to evaluate the effectiveness of the playback method to estimate the density of calling males. We compared playback method with spontaneous calling of males at dawn and direct observations along transects. The results on raw count data of playback counts revealed a strong underestimation rate compared to the method that gave the best results: count of spontaneous calls at dawn. Our study provides a critical evaluation of a method that is widely used even though data about its effectiveness are scarce. Our data do not evaluate detection probability of the three methods. Our aim was only to evaluate which methods give the best results in term of population size estimation under the same field condition (same population density, same period, same monitoring area). The results raise some doubts about the ability of the playback method to monitor red–legged partridge populations. The implications of our results for red–legged population management are discussed.

scholarly journals Lyell, the Geikies and Croll's observations on terrestrial glacial sediments and landforms

2021 ◽  
pp. 1-14
Author(s):  
James ROSE
Keyword(s):  
Climate Change ◽  
High Quality ◽  
Glacial Sediments ◽  
Direct Observations ◽  
The Social ◽  
The Status ◽  
Social And Physical Environment ◽  
Glacial Landforms

ABSTRACT Within the context of the work and achievements of James Croll, this paper reviews the records of direct observations of glacial landforms and sediments made by Charles Lyell, Archibald and James Geikie and James Croll himself, in order to evaluate their contributions to the sciences of glacial geology and Quaternary environmental change. The paper outlines the social and physical environment of Croll's youth and contrasts this with the status and experiences of Lyell and the Geikies. It also outlines the character and role of the ‘Glasgow School’ of geologists, who stimulated Croll's interest into the causes of climate change and directed his focus to the glacial and ‘interglacial’ deposits of central Scotland. Contributions are outlined in chronological order, drawing attention to: (i) Lyell's high-quality observations and interpretations of glacial features in Glen Clova and Strathmore and his subsequent rejection of the glacial theory in favour of processes attributed to floating icebergs; (ii) the significant impact of Archibald Geikie's 1863 paper on the ‘glacial drift of Scotland’, which firmly established the land-ice theory; (iii) the fact that, despite James Croll's inherent dislike of geology and fieldwork, he provided high-quality descriptions and interpretations of the landforms and sediments of central Scotland in order to test his theory of climate change; and (iv) the great communication skills of James Geikie, enhanced by contacts and evidence from around the world. It is concluded that whilst direct observations of glacial landforms and sediments were critical to the long-term development of the study of glaciation, the acceptance of this theory was dependent also upon the skills, personality and status of the Geikies and Croll, who developed and promoted the concepts. Sadly, the subsequent rejection of the land-ice concept by Lyell resulted in the same factors challenging the acceptance of the glacial theory.

scholarly journals Advancement in long-distance bird migration through individual plasticity in departure

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jesse R. Conklin ◽  
Simeon Lisovski ◽  
Phil F. Battley
Keyword(s):  
Bird Migration ◽  
Population Level ◽  
Breeding Site ◽  
Environmental Constraints ◽  
Adaptive Responses ◽  
Long Distance ◽  
Direct Observations ◽  
Breeding Resources ◽  
Plastic Responses

AbstractGlobally, bird migration is occurring earlier in the year, consistent with climate-related changes in breeding resources. Although often attributed to phenotypic plasticity, there is no clear demonstration of long-term population advancement in avian migration through individual plasticity. Using direct observations of bar-tailed godwits (Limosa lapponica) departing New Zealand on a 16,000-km journey to Alaska, we show that migration advanced by six days during 2008–2020, and that within-individual advancement was sufficient to explain this population-level change. However, in individuals tracked for the entire migration (50 total tracks of 36 individuals), earlier departure did not lead to earlier arrival or breeding in Alaska, due to prolonged stopovers in Asia. Moreover, changes in breeding-site phenology varied across Alaska, but were not reflected in within-population differences in advancement of migratory departure. We demonstrate that plastic responses can drive population-level changes in timing of long-distance migration, but also that behavioral and environmental constraints en route may yet limit adaptive responses to global change.

scholarly journals Long-Term and Emergency Monitoring of Zhongbao Landslide Using Space-Borne and Ground-Based InSAR

2021 ◽  
Vol 13 (8) ◽  
pp. 1578
Author(s):  
Ting Xiao ◽  
Wei Huang ◽  
Yunkai Deng ◽  
Weiming Tian ◽  
Yonglian Sha
Keyword(s):  
Landslide Monitoring ◽  
Early Investigation ◽  
Interferometric Synthetic Aperture Radar ◽  
Monitoring Methods ◽  
Barrier Lake ◽  
Monitoring Frequency ◽  
Emergency Measure ◽  
Cumulative Deformation ◽  
Timely Warning

This work presents the ideal combination of space-borne and ground-based (GB) Interferometric Synthetic Aperture Radar (InSAR) applications. In the absence of early investigation reporting and specialized monitoring, the Zhongbao landslide unexpectedly occurred on 25 July 2020, forming a barrier lake that caused an emergency. As an emergency measure, the GB-InSAR system was installed 1.8 km opposite the landslide to assess real-time cumulative deformation with a monitoring frequency of 3 min. A zone of strong deformation was detected, with 178 mm deformation accumulated within 15 h, and then a successful emergency warning was issued to evacuate on-site personnel. Post-event InSAR analysis of 19 images acquired by the ESA Sentinel-1 from December 2019 to August 2020 revealed that the landslide started in March 2020. However, the deformation time series obtained from satellite InSAR did not show any signs that the landslide had occurred. The results suggest that satellite InSAR is effective for mapping unstable areas but is not qualified for rapid landslide monitoring and timely warning. The GB-InSAR system performs well in monitoring and providing early warning, even with dense vegetation on the landslide. The results show the shortcomings of satellite InSAR and GB-InSAR and a clearer understanding of the necessity of combining multiple monitoring methods.

Condition Monitoring Methodology for Manufacturing and Design

1998 ◽  
Author(s):  
Irem Y. Tumer ◽  
Kristin L. Wood ◽  
Ilene J. Busch-Vishniac
Keyword(s):  
Milling Process ◽  
Monitoring Methods ◽  
Design And Manufacturing ◽  
Systematic Methodology ◽  
Surface Deviations ◽  
Part Surface ◽  
Tool Vibrations ◽  
Changes Over Time ◽  
Part Production ◽  
Manufacturing Data

Abstract Part production requires constant monitoring to assure the effective manufacturing of high-quality components. The choice of monitoring methods can become a crucial factor in the decisions made during and prior to manufacturing. In an ideal world, designers and manufacturers will work together to interpret manufacturing and part data to assure the elimination of faults in manufacturing. However, manufacturing still lacks mathematically robust means of interpreting the manufacturing data so that a channel of communication can be established between design and manufacturing. To address part production concerns, we present a systematic methodology to interpret manufacturing data based on signals from manufacturing (e.g., tool vibrations, part surface deviations). These signals are assumed to contain a fingerprint of the manufacturing condition. The method presented in this paper is based on a mathematical transform to decompose the signals into their significant modes and monitor their changes over time. The methodology is meant to help designers and manufacturers make informed decisions about a machine and/or part condition. An example from a milling process is used to illustrate the method’s details.

The Long-Term Effects of Grief on Marital Intimacy following an Infant's Death

1996 ◽  
Vol 33 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Laurie N. Gottlieb ◽  
Ariella Lang ◽  
Rhonda Amsel
Keyword(s):  
Home Visit ◽  
Sexual Intimacy ◽  
Long Term Effects ◽  
Emotional Intimacy ◽  
Significant Drop ◽  
Marital Intimacy ◽  
Grief Responses ◽  
Changes Over Time

This follow-up study examined how marital intimacy changes over time in bereaved couples and how their marriages are affected by the death of their infant. A group of thirty-one bereaved couples who two to four years earlier had lost an infant (> 20 weeks gestation and < 1 year of age) were revisited in their home twenty-four months after the initial home visit. Couples did report a significant drop in sexual intimacy at follow-up compared to before the loss and at the initial home visit. Moreover, wives reported less emotional intimacy overall, than did their husbands. In contrast to wives whose own initial grief responses predicted their feelings about their marriages two years later, intensity of husband's initial grief response did not affect their relationship with their wives but, rather a more powerful predictor was their wives' initial reactions, the early state of their marriage (whether they had considered separating), and whether or not they had warning of the impending death. Finally, there is some evidence that women are affected in part, by their husbands' grief.

scholarly journals EM-Based Monitoring and Probabilistic Analysis of Prestress Loss of Bonded Tendons in PSC Beams

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Zheheng Chen ◽  
Shanwen Zhang
Keyword(s):  
Probabilistic Analysis ◽  
Prestressed Concrete ◽  
Monitoring Methods ◽  
Prestress Loss ◽  
External Tendons ◽  
Material Environment ◽  
Key Factor ◽  
One Year

The prestress level is a key factor of prestressed concrete (PSC) beams, affecting their long-term serviceability and safety. Existing monitoring methods, however, are not effective in obtaining the force or stress of embedded tendons. This paper investigates the feasibility of elastomagnetic (EM) sensors, which have been used for external tendons, in monitoring the long-term prestress loss of bonded tendons. The influence of ambient temperature, water, eccentricity ratio, plastic duct, and cement grouts on the test results of EM sensors is experimentally examined. Based on the calibrated EM sensors, prestress loss of a group of PSC beams was monitored for one year. In order to further consider the high randomness in material, environment, and construction, probabilistic analysis of prestress loss is conducted. Finally, the variation range of prestress loss with a certain confidence level is obtained and is compared with the monitored data, which provides a basis for the determination of prestress level in the design of PSC beams.

scholarly journals Assessing Summer Pond and Lake Inlet Use by Gray Treefrogs (Hyla versicolor/chrysoscelis complex) Using PVC Pipe Traps in Northwest Missouri

2020 ◽  
Vol 48 (2020) ◽  
pp. 17-21
Author(s):  
J. D. McGhee
Keyword(s):  
Sex Ratio ◽  
Hyla Versicolor ◽  
Monitoring Methods ◽  
Contingency Table Analysis ◽  
Detection Rates ◽  
Sampling Locations ◽  
Table Analysis ◽  
Pvc Pipe ◽  
Gray Treefrog

Abstract The widespread decline in amphibian populations highlights the need for establishing rigorous monitoring methods for long-term population studies. In an attempt to launch a long-term monitoring study for a Gray Treefrog complex (Hyla versicolor LeConte /chrysoscelis Cope, hereafter treefrog) population in northwest Missouri, I tested the use of PVC pipe traps in a system of ponds and inlets along a lakeside habitat for three years. For each pond (3) and inlet (2), I established an array of 16 pipes so as to compare differences in use between pipe location, ponds and inlets, and sex ratio between sites. Pipes were checked twice a week during the summer for the presence of treefrogs. Treefrog usage of pipes between ponds and inlets were compared using a contingency table analysis, while an ANOVA was used to assess differences in sex ratios between sites (α = 0.05). A single inlet was used by treefrogs more heavily than the other ponds or inlet (G = 13.61, df = 3, P = 0.0035), however, I found no differences in terms of pipe location within a pond or inlet. Mean sex ratio between water bodies varied but did not significantly differ. There appears to be little effect in terms of pipe placement within our 50 m buffer from the water's edge, but unique habitat effects at sampling locations may significantly affect detection rates or usage.

scholarly journals Wind plants can impact long-term local atmospheric conditions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nicola Bodini ◽  
Julie K. Lundquist ◽  
Patrick Moriarty
Keyword(s):  
Wind Speed ◽  
Urban Areas ◽  
Weather Prediction ◽  
Atmospheric Conditions ◽  
Near Surface ◽  
Direct Observations ◽  
Stable Conditions ◽  
Weather And Climate ◽  
Central United States

AbstractLong-term weather and climate observatories can be affected by the changing environments in their vicinity, such as the growth of urban areas or changing vegetation. Wind plants can also impact local atmospheric conditions through their wakes, characterized by reduced wind speed and increased turbulence. We explore the extent to which the wind plants near an atmospheric measurement site in the central United States have affected their long-term measurements. Both direct observations and mesoscale numerical weather prediction simulations demonstrate how the wind plants induce a wind deficit aloft, especially in stable conditions, and a wind speed acceleration near the surface, which extend $$\sim 30$$ ∼ 30  km downwind of the wind plant. Turbulence kinetic energy is significantly enhanced within the wind plant wake in stable conditions, with near-surface observations seeing an increase of more than 30% a few kilometers downwind of the plants.

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