USE OF TRAPS BAITED WITH VIRGIN FEMALES FOR FIELD OBSERVATIONS ON THE BERTHA ARMYWORM (LEPIDOPTERA: NOCTUIDAE)

1975 ◽  
Vol 107 (7) ◽  
pp. 781-784 ◽  
Author(s):  
G. E. Swailes ◽  
D. L. Struble ◽  
N. D. Holmes

AbstractCylindrical traps with screen cones at the ends baited with virgin females and placed in rape fields about 1 m above ground level were effective in trapping males of the bertha armyworm. Males were most active between 0330 and 0430 h M.D.T. and moved precisely to confined females. Virgin females became attractive 1 day after emergence and remained attractive for at least 7 days. Trapping was an effective method for rapidly determining the presence of bertha armyworm.

1982 ◽  
Vol 114 (12) ◽  
pp. 1121-1125 ◽  
Author(s):  
H. H. Cheng ◽  
D. L. Struble

AbstractField tests were conducted annually near Delhi, Ontario from 1977 to 1981 to evaluate blacklight and sex attractant traps for monitoring adult populations of the darksided cutworm, Euxoa messoria (Harris), in the major tobacco-producing area. There were no significant differences between the catches of sex attractant traps set at 1.0 m and 0.5 m above ground level. Sex attractant traps were superior to blacklight traps for monitoring populations of this pest species. There was a variation in abundance from year to year, but the time of peak occurrence of E. messoria adults was the same in each of the 5 years.


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.


2009 ◽  
Vol 48 (8) ◽  
pp. 1627-1642 ◽  
Author(s):  
P. Baas ◽  
F. C. Bosveld ◽  
H. Klein Baltink ◽  
A. A. M. Holtslag

Abstract A climatology of nocturnal low-level jets (LLJs) is presented for the topographically flat measurement site at Cabauw, the Netherlands. LLJ characteristics are derived from a 7-yr half-hourly database of wind speed profiles, obtained from the 200-m mast and a wind profiler. Many LLJs at Cabauw originate from an inertial oscillation, which develops after sunset in a layer decoupled from the surface by stable stratification. The data are classified to different types of stable boundary layers by using the geostrophic wind speed and the isothermal net radiative cooling as classification parameters. For each of these classes, LLJ characteristics like frequency of occurrence, height above ground level, and the turning of the wind vector across the boundary layer are determined. It is found that LLJs occur in about 20% of the nights, are typically situated at 140–260 m above ground level, and have a speed of 6–10 m s−1. Development of a substantial LLJ is most likely to occur for moderate geostrophic forcing and a high radiative cooling. A comparison with the 40-yr ECMWF Re-Analysis (ERA-40) is added to illustrate how the results can be used to evaluate the performance of atmospheric models.


1988 ◽  
Vol 120 (5) ◽  
pp. 401-413 ◽  
Author(s):  
W. J. Turnock

AbstractPopulations of larvae of the bertha armyworm, Mamestra configurata Wlk., in four physiographic regions of Manitoba showed similar trends over time: a decline from the outbreak of 1971–1972 to very low densities in 1975–1977, an increase to a peak during the years 1979–1981, and a subsequent decline. During the period of peak larval populations, brief (1 or 2 years) outbreaks [at least some fields with > 20 larvae per square metre) occurred at five locations in two regions, the Swan River Plain and the Valley River Plain, but not in the Western Uplands or the Manitoba Lowlands. In the first two regions, larval densities rose rapidly (from < 1.6 to > 13.8/m2) in 1 year. Although the general trend of population density was similar, there were differences in density among and within regions, and in the timing, severity, and duration of peak populations. Two parasitoids (Banchus flavescens Cress., Athrycia cinerea (Coq.)) and two pathogens (a nuclear polyhedrosis virus (NPV) and fungi of the Entomophthorales) occurred regularly in larval populations. Of these, B. flavescens had the highest constancy among collections and may help to keep bertha armyworm populations at low densities. NPV was rarely found among larvae from low-density populations but appeared in all populations that reached outbreak levels. No single biotic agent could be associated with the population declines because of multiple parasitism and the difficulty in partitioning mortality when only a single sample could be taken. The rapid increase of bertha armyworm larvae from very low to outbreak levels in 1 year will prevent predictions of outbreaks from being based on larval densities in the preceding year.


2021 ◽  
Vol 27 (1) ◽  
pp. 20-25
Author(s):  
Ziyad Khalf Salih ◽  
Seyedeh Somayyeh Shafiei Masouleh ◽  
Mohamed Abdulla Ahmed ◽  
Marwan Abdulla Sanam

Abstract Jasmine (Jasminum sambac L.) is an evergreen shrub and very fragrant, which has a very importance in the perfume industry and its flowers are used in different religious and ceremonies. Training the shrubs for more yields of flowers and essential oil with horticultural improvement effects of pruning and amino acids may help gardeners to achieve more benefits. This study aimed to investigate the effects of pruning intensity (without pruning, 40, 60 or 75 cm above ground level) and foliar application of amino acids (without amino acids, tryptophan or glycine) on jasmine shrubs for promoting growth and reproductive growth and the content of essential oil. The results showed that plants with light pruning (75 cm) and foliar application of amino acids especially glycine had the best growth and yield, which means that plants were affected by the interactions of pruning level and application of amino acids.


2009 ◽  
Vol 2 (4) ◽  
pp. 2027-2054 ◽  
Author(s):  
R. Häseler ◽  
T. Brauers ◽  
F. Holland ◽  
A. Wahner

Abstract. The LOPAP (long path absorption) technique has been shown to be very sensitive for the detection of nitrous acid (HONO) in the atmosphere. However, current instruments were mainly built for ground based applications. Therefore, we designed a new LOPAP instrument to be more versatile for mobile measurements and to meet the requirements for airborne application. The detection limit of the new instrument is below 1 ppt at a time resolution of 5 to 7 min. As a first test, the instrument was successfully employed during the ZEPTER-1 campaign in July 2007 on board of the Zeppelin NT airship. During 15 flights on six days we measured HONO concentration profiles over southwest Germany, predominantly in the range between 100 m and 650 m above ground level. On average, a mixing ratio of 34 ppt was observed, almost independently of height. Within a econd campaign, ZEPTER-2 in fall 2008, higher HONO mixing ratios were observed in the Lake Constance area.


1983 ◽  
Vol 115 (8) ◽  
pp. 1039-1042 ◽  
Author(s):  
B. M. Hegdekar

AbstractThe critical photoperiod for diapause induction in pupae of Mamestra configurata Walker in Manitoba was 16 h 06 min at Glenlea (49°38′ N), 16 h 20 min at Grandview (51°10′ N), and 16 h 42 min at Birch River (52°24′ N). The differences in cirtical photoperiods observed at Glenlea and Grandview were not significant. At least two different photoperiods exist, one in the Glenlea and Grandview areas and the other in the Birch River area. In the laboratory, the critical photoperiod was 13.5 h when larvae were exposed to a daily fluctuating temperature regime of 12 h at 25 °C and 12 h at 10 °C. Longer critical photoperiods found for the field populations may be related to the relatively low ambient temperatures to which the larvae were exposed in field cages.


2021 ◽  
Author(s):  
Pauline Le Maire ◽  
Denis Thieblemont ◽  
Marc Munschy ◽  
Guillaume Martelet ◽  
Geoffroy Mohn

&lt;p&gt;Continent-Ocean Transitions (COT) and ultra-slow spreading ridges, floored by wide area of exhumed serpentinized mantle, bear strong amplitude magnetic lineations. However, whether these anomalies are linked to inversions of the direction of the magnetization (therefore characterized as isochrones of seafloor spreading) or to structural and lithological contrasts remains an open question. Generally, marine magnetic data acquired at sea surface along profiles, are too low resolution to image the intensity variations of the magnetic field at a kilometric scale. Performing a dense deep tow magnetic survey at a present-day COT or ultra-slow spreading system would be better to determine the sources of the magnetic signal but remains expensive. To go ahead, a valuable alternative to address these questions is to record the magnetic signal on ophiolite representing remnants of COT and oceanic systems sampled in orogenic system. We worked on the Chenaillet Ophiolite (French Alps), which represents a fossil COT or ultra-slow spreading system integrated to the Alpine orogeny. This ophiolite escaped high-pressure metamorphism and has only been weakly deformed during Alpine orogeny, preserving its pre-orogenic structure.&lt;/p&gt;&lt;p&gt;We performed an UAV magnetic survey using fluxgate magnetometers in complex conditions due to the altitude (&gt; 1800 m), the strong topography variations and the weather conditions (negative temperatures, snow). Despite these difficulties, which highlight the viability of UAV for geophysical measurements, a survey of 20 square kilometers with 219 km of profiling was completed 100 m above ground level. Flight line spacing is 100 m above the ophiolitic basement and 200 m above the sedimentary units. Another magnetic UAV survey was flown with another UAV to map a small area 10 m above ground level. Magnetic anomaly maps were computed after standard processing (e.g., calibration/compensation, temporal variation and regional magnetic field corrections, levelling).&lt;/p&gt;&lt;p&gt;Our first results evidence well-defined magnetic anomalies clearly linked to serpentinite. This shows that the magnetic signal is of sufficient resolution to contribute to a revision of the cartography of the massif combining geological observations and magnetic data.&lt;/p&gt;&lt;p&gt;In addition, the magnetic susceptibility was measured on 60 outcrops, to support interpretation.&lt;/p&gt;&lt;p&gt;In this presentation, we focus on the magnetic acquisition campaigns, processing and 2D/3D interpretations by forward modelling and data inversion. Lastly, two items are discussed: 1) contribution of magnetic UAV surveys for geological mapping; and 2) implication of the results on the Chenaillet massif to discuss the contribution of magnetic mapping to the understanding of the TOC or ultra-slow spreading system.&lt;/p&gt;


Author(s):  
Stephen J. Curran

This paper is a pilot study on the concept of an aerial base station as a future strategy for restoring cellular communications in the aftermath of a major disaster. The strategy being studied makes use of low altitude platforms (LAPs) or unmanned aerial vehicles (UAVs) that can hover or orbit in a relatively fixed position and can act as an aerial base station. Unlike High Altitude Platforms (HAP) operating in a layer of the atmosphere above any existing air traffic, the LAPs or UAVs will be able to operate a few hundred to some thousands of meters above ground level. This paper also describes the functionality of the components comprising the aerial base station.


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