scholarly journals Daily Foraging Activity of Acromyrmex (Hymenoptera: Formicidae) Leaf-cutting ants

Sociobiology ◽  
2016 ◽  
Vol 63 (1) ◽  
pp. 645 ◽  
Author(s):  
Mariane Aparecida Nickele ◽  
Wilson Reis Filho ◽  
Marcio Roberto Pie ◽  
Susete Do Rocio Chiarello Penteado
Keyword(s):  
Foraging Ecology ◽  
Weather Conditions ◽  
Time Of Day ◽  
Economic Damage ◽  
Forest Plantations ◽  
Foraging Activity ◽  
Southern Brazil ◽  
Leaf Cutting ◽  
Favorable Conditions

Leaf-cutting ants are well-known insects due to their remarkable activity as herbivores and the considerable economic damage they cause to many crops. The identification of season and time of day when leaf-cutting ants are most active is an important tool, not just to understand the foraging ecology of these ants, but also to optimize their control in plantation areas where they were pests. Thus, the aims of this study are to evaluate the daily foraging activity of leaf-cutting ant species of the genus Acromyrmex, which occur in forest plantations in Southern Brazil. Foraging activity of Acromyrmex crassispinus (Forel) and Acromyrmex subterraneus subterraneus (Forel) were correlated with weather conditions, and it was more intense during spring and summer. Workers that forage at night are significantly heavier than workers that forage during the day. This study showed that A. crassispinus and A. subterraneus subterraneus did not forage at temperatures below 10-11°C. Then, the use of granulated baits to control these leaf-cutting ants species where they were pests should be done just under favorable conditions of temperature for Acromyrmex foraging activity (over 12°C), to ensure maximum collection of baits by ants and the least left-over baits.

REAL CONDITION AND PROSPECTS OF DEVELOPMENT OF THE RADAR STATIONS OF THE COUNTER BATTERY FIGHTINGV

2019 ◽  
Vol 1 (12) ◽  
pp. 30-40
Author(s):  
V. Нolovan ◽  
V. Gerasimov ◽  
А. Нolovan ◽  
N. Maslich
Keyword(s):  
Comparative Analysis ◽  
Real Time ◽  
Weather Conditions ◽  
Time Of Day ◽  
Current Position ◽  
Real Condition ◽  
Leading Role ◽  
Artillery Shell

Fighting in the Donbas, which has been going on for more than five years, shows that a skillful counter-battery fight is an important factor in achieving success in wars of this kind. Especially in conditions where for the known reasons the use of combat aviation is minimized. With the development of technical warfare, the task of servicing the counter-battery fight began to rely on radar stations (radar) to reconnaissance the positions of artillery, which in modern terms are called counter-battery radar. The principle of counter-battery radar is based on the detection of a target (artillery shell, mortar mine or rocket) in flight at an earlier stage and making several measurements of the coordinates of the current position of the ammunition. According to these data, the trajectory of the projectile's flight is calculated and, on the basis of its prolongation and extrapolation of measurements, the probable coordinates of the artillery, as well as the places of ammunition falling, are determined. In addition, the technical capabilities of radars of this class allow you to recognize the types and caliber of artillery systems, as well as to adjust the fire of your artillery. The main advantages of these radars are:  mobility (transportability);  inspection of large tracts of terrain over long distances;  the ability to obtain target's data in near real-time;  independence from time of day and weather conditions;  relatively high fighting efficiency. The purpose of the article is to determine the leading role and place of the counter-battery radar among other artillery instrumental reconnaissance tools, to compare the combat capabilities of modern counter-battery radars, armed with Ukrainian troops and some leading countries (USA, China, Russia), and are being developed and tested in Ukraine. The method of achieving this goal is a comparative analysis of the features of construction and combat capabilities of modern models of counter-battery radar in Ukraine and in other countries. As a result of the conducted analysis, the directions of further improvement of the radar armament, increasing the capabilities of existing and promising counter-battery radar samples were determined.

When, where and why do people encounter Australian brownsnakes (Pseudonaja textilis : Elapidae)?

1999 ◽  
Vol 26 (5) ◽  
pp. 675 ◽  
Author(s):  
P. B. Whitaker ◽  
R. Shine
Keyword(s):  
Air Temperature ◽  
Agricultural Land ◽  
New South ◽  
Habitat Type ◽  
Weather Conditions ◽  
Time Of Day ◽  
South Wales ◽  
Experienced Observer ◽  
Close Proximity ◽  
Species Ecology

Encounters between humans and dangerously venomous snakes put both participants at serious risk, so the determinants of such encounters warrant attention. Pseudonaja textilis is a large fast-moving elapid snake responsible for most snakebite fatalities in Australia. As part of a broad ecological study of this species in agricultural land near Leeton, New South Wales, we set out to identify factors influencing the probability that a human walking in farmland would come into close proximity to a brownsnake. Over a three-year period, we walked regular transects to quantify the number and rate of snake encounters, and the proportion of snakes above ground that could be seen. The rate of encounters depended upon a series of factors, including season, time of day, habitat type, weather conditions (wind and air temperature) and shade (light v. dark) of the observers’ clothing. Interactions between factors were also important: for example, the effect of air temperature on encounter probability differed with season and snake gender, and the effect of the observers’ shade of clothing differed with cloud cover. Remarkably, even a highly-experienced observer actually saw <25% of the telemetrically monitored snakes that were known to be active (i.e. above ground) nearby. This result reflects the snakes’ ability to evade people and to escape detection, even in the flat and sparsely vegetated study area. The proportion of snakes that were visible was influenced by the same kinds of factors as described above. Most of the factors biasing encounter rates are readily interpretable from information on other facets of the species’ ecology, and knowledge of these factors may facilitate safer coexistence between snakes and people.

scholarly journals Parasites of beetles which are pests of grain and products of its processing

2018 ◽  
Vol 25 (4) ◽  
Author(s):  
V. O. Martynov
Keyword(s):  
Biological Control ◽  
Natural Enemies ◽  
Callosobruchus Maculatus ◽  
Ecological Condition ◽  
Rhyzopertha Dominica ◽  
Economic Damage ◽  
Crop Pests ◽  
Main Crop ◽  
Anisopteromalus Calandrae ◽  
Favorable Conditions

Crop pests are the cause of economic damage in many developing countries, including Ukraine, where annual loss of crop harvest on average equals 6 million tons, valued at 840 million dollars. Pests consume grain, causing its pollution and creating favorable conditions for development of mold, which significantly decreases the food and seeding properties of grain and products of its processing. This article presents basic data on biological control and its advantages, demonstrates the variety of natural enemies of the pest beetles, which are used in biological control, analyses studies of the biological control of main crop pests and products of its processing belonging to the families Curculionidae and Tenebrionidae, and also the role of competition in  biological control. The analysis of studies on the effectiveness of different natural enemies of the main crop pest-beetles shows that the most studied parasites are Sitophilus granarius, S. zeamais, Tribolium confusum, T. castaneum, Oryzaephilus surinamensis, Rhyzopertha dominica, Acanthoscelides obtectus and Callosobruchus maculatus. Natural enemies of the rest of the species are poorly studied, and there is no data on Caulophilus latinasus, Tenebroides mauritanicus, Dermestes lardarius, Ptinus fur and Bruchidius incarnatus. The most commonly used natural enemies are Xylocoris flavipes, Anisopteromalus calandrae, the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana, and also nematodes of the Steinernema and Heterorhabditis genera. Despite the broad spectrum of natural enemies of the main pests of the grain supply, it is necessary to further study the parasites of every species of beetle which causes economic damage. Using biological control is the most promising method against pests of crops and products of its processing, which meets the current requirements to the sanitary-ecological condition of agricultural production.

scholarly journals Promising varieties of spring glumaceous oat of the mowing and grain-mowing directions, adapted to the natural and climatic conditions of the Volga-Vyatka region

2021 ◽  
Vol 36 ◽  
pp. 01003
Author(s):  
Elena Vologzhanina ◽  
Galina Batalova
Keyword(s):  
Weather Conditions ◽  
Climatic Conditions ◽  
High Yield ◽  
Positive Dependence ◽  
Green Mass ◽  
North East ◽  
The North ◽  
Temperature And Precipitation ◽  
Green Mass Yield ◽  
Favorable Conditions

The results of the study of 12 varieties and promising lines of glumaceous oat in the competitive variety testing of the FASC of the North-East (Kirov region) in the period from 2018 to 2020 are presented. The purpose of the research is to assess the productivity, ecological plasticity and stability of the genotypes of glumaceous oat for feed and universal use in the conditions of the Volga-Vyatka region. The dependences of grain yield and dry matter harvesting on the state of agro-climatic resources (HTC), temperature and precipitation are established. The contrasting weather conditions during the years of research allowed to conduct the most complete assessment of the studied genotypes. The most favorable conditions for the formation of a high yield of green mass of oat were formed in 2020 (Ij=3.76), grain - in 2019 (Ij=1.35). The average degree of positive dependence of green mass yield on the height of oat plants was revealed (r=0.51). The variety of the high-intensity type of the universal direction Medved, promising lines of the mowing direction (178h13 and 245h14) are distinguished.

scholarly journals Economic Value of Improving Natural Gas Supply Reliability for Residential Consumers in South Korea

2019 ◽  
Vol 11 (2) ◽  
pp. 515 ◽  
Author(s):  
Hyo-Jin Kim ◽  
Sung-Min Kim ◽  
Seung-Hoon Yoo
Keyword(s):  
Natural Gas ◽  
Economic Value ◽  
Time Of Day ◽  
Economic Damage ◽  
South Korean Government ◽  
South Korean ◽  
Day Of The Week ◽  
Gas Supply ◽  
Supply Reliability ◽  
Residential Consumers

An interruption to residential natural gas (NG) may cause considerable economic damage of the entire country. Thus, the South Korean government requires information about the economic value of improving residential NG supply reliability for planning NG supply. This article aims to measure the value using a specific case of South Korean residential consumers. The choice experiment (CE) approach was adopted for this purpose. The selected four attributes are the duration of interruption, the season of interruption, the time of day, and the day of the week. The value trade-off works among the four attributes and price attribute were sought and completed in a nationwide CE survey of 1000 households. The respondents revealed statistically significant willingness to pay for a decrease in the duration of interruption, avoiding interruption during winter rather than non-winter, and preventing interruption during off-daytime (18:00 to 09:00) rather than daytime (09:00 to 18:00). For example, they accepted a 0.10% increase in the residential NG bill for a one-minute reduction in interruption during NG supply interruption, a 5.16% increase in residential NG bill for avoiding interruption during winter rather than non-winter, and a 2.94% increase in residential NG bill for preventing interruption during off-daytime rather than daytime. However, they placed no importance on the day of the week. These results can be useful for policy-making and decision-making to improve residential NG supply reliability. It is necessary to conduct a study at regular intervals on the value of NG supply reliability because regarding NG supply reliability, it is difficult to maintain a specific value.

scholarly journals Genetic variability and social structure of colonies in Acromyrmex heyeri and A. striatus (Hymenoptera: Formicidae)

2001 ◽  
Vol 61 (4) ◽  
pp. 667-678 ◽  
Author(s):  
E. DIEHI ◽  
A. M. de ARAÚJO ◽  
S. CAVALLI-MOLINA
Keyword(s):  
Genetic Variability ◽  
Social Structure ◽  
Rio Grande ◽  
Genotypic Diversity ◽  
Inbreeding Coefficient ◽  
Southern Brazil ◽  
Rio Grande Do Sul ◽  
Nuptial Flight ◽  
The Social ◽  
Leaf Cutting

The breeding structure of both colony and population of social insects can be examined by genetic analysis. Colonies of the leaf-cutting ants Acromyrmex heyeri and A. striatus (Myrmicinae, Attini) were thus analyzed for isoenzyme systems MDH, a-GPDH, and AMY to describe genotype variability and social structure. A total of five loci were investigated (three for amylase and one for each other system). Ninety-seven colonies of A. heyeri and 103 of A. striatus were sampled in different localities in Southern Brazil (State of Rio Grande do Sul). The genotypes found show the occurrence of monogyny and polygyny associated or not with polyandry, which indicates that the social organization is colony-specific. The polygyny and polyandry observed are likely to be responsible for the great genotypic diversity of the colonies. The average inbreeding coefficient per colony was higher in A. striatus than in A. heyeri, which may reflect the different patterns of production of sexual individuals and nuptial flight of those two species.

scholarly journals Comparison of Hydrogen Sulfide Concentrations and Odor Annoyance Frequency Predictions Downwind from Livestock Facilities

Atmosphere ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 249
Author(s):  
Suraiya Akter ◽  
Erin L. Cortus
Keyword(s):  
Hydrogen Sulfide ◽  
Single Point ◽  
Weighted Average ◽  
Weather Conditions ◽  
Time Of Day ◽  
Dispersion Modeling ◽  
Emission Rates ◽  
Weather Patterns ◽  
Odor Emission ◽  
Odor Annoyance

Estimating and measuring the occurrence of a sensation, odor, around livestock facilities is challenging. This research compares the estimated frequency of odor nuisance with measured hydrogen sulfide (H2S) concentrations at various distances around a swine and a dairy operation, and discusses the results based on time of day, weather conditions, distance, and topography. The estimated odor annoyance-free and odor annoyance frequencies were based on a publically available calculator of odor impact derived from average odor emission rates, historical, and regional weather patterns, and dispersion modeling. Continuous monitoring of H2S was by single point monitors (SPM) at locations around the operations. Time-weighted average H2S concentrations were less than 10 ppb for odor annoyance-free frequencies, and less than 10 to at least 73 ppb for odor-annoyance frequencies. Verifying a proxy odor indicator can help update odor annoyance models and respond to site-specific concerns for existing facilities.

Hemolymph homeostasis in relation to diel feeding activity and microclimate in the prototypal land isopod Ligia pallasii

2000 ◽  
Vol 78 (4) ◽  
pp. 588-595 ◽  
Author(s):  
Thomas H Carefoot ◽  
Jonathan Wright ◽  
Steven C Pennings ◽  
Andreas Ziegler ◽  
Martin Zimmer ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Feeding Activity ◽  
Weather Conditions ◽  
Time Of Day ◽  
Field Population ◽  
Dietary Salt ◽  
Salt Loading ◽  
Terrestrial Isopods ◽  
Osmotic Homeostasis ◽  
Colonization Of Land

Twenty-four-hour variability in hemolymph osmolality was assessed in a field population of the semiterrestrial isopod Ligia pallasii and related to feeding activity and microenvironmental conditions of relative humidity (RH) and temperature in the species' habitats. Hemolymphs were also analyzed for levels of ammonia and glucose as indicators of digestive and absorptive activities. Comparative data on hemolymph osmolality and microhabitat conditions were also obtained for several ligiid species in Hawai'i. Late-morning peaks in hemolymph osmolality in L. pallasii were coincidental with peaks in ammonia and glucose and with predicted times of digestion/absorption based on observed feeding activity in the population, suggesting that the elevations in osmolality were due to salt-loading from the species' seaweed diet. Uniformity of microenvironmental conditions of RH and temperature in Ligia's supralittoral habitat, whether temperate or tropical, and regardless of time of day or localized weather conditions, suggests that dietary salt-loading is likely the greatest challenge to osmotic homeostasis in ligiids. This feature and other aspects of hemolymph osmolality in ligiids are discussed in the context of colonization of land by prototypal terrestrial isopods.

Distribution and diversity of leaf-cutting ants in Northeastern Argentina: species most associated with forest plantations

2019 ◽  
Vol 65 (3) ◽  
pp. 244-257 ◽  
Author(s):  
Andrés F. Sánchez-Restrepo ◽  
Nadia L. Jiménez ◽  
Viviana A. Confalonieri ◽  
Luis A. Calcaterra
Keyword(s):  
Forest Plantations ◽  
Leaf Cutting ◽  
Northeastern Argentina
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