scholarly journals Influence of meteorological factors on weakening of elm trees under conditions of development of insect-xylophages

2020 ◽  
Vol 11 (3) ◽  
Author(s):  
N. V. Puzrina ◽  
M. I. Yavniy
Keyword(s):  
Insect Pests ◽  
Research Area ◽  
Dead Trees ◽  
Low Degree ◽  
Abrupt Changes ◽  
Mass Reproduction ◽  
Undetermined Etiology ◽  
Xylophagous Insects ◽  
New Settlements ◽  
Sanitary State

The biological resistance of species of the genus Ulmus L. is interrelated with various biotic, abiotic and anthropic factors, in particular, abrupt changes in the hydrothermal regime, failure to comply with the rules of intermediate cutting management in the stands with these species, damage by leaf and stem insect pests that transmit and spread the infection, infectious agents, agents of undetermined etiology, etc.It has been discovered that the uneven distribution of rainfall over the years (the least rain in the research area fell in 2007, 2009 and 2015) induced deterioration of the sanitary state of elm woody plants, which caused them being affected by pathogens of mushroom and bacterial etiology and their settlement by xylophagous insects. On the basis of the analysis of changes in the population parameters in the phases of the development of the hotbeds of these pests it was shown that the studied plantations in the dynamics during the period from 2004 to 2006 were in a state of dispersion or the so-called crisis, but, starting from 2007, transformed into a state of the actual outbreak of the hotbed. Detected hotbeds of stem pests are characterized by high, medium and low degree of settlement of trees. At the same time, it was recorded that chronic hotbeds are characterized by a long period of existence, relatively low, although elevated (in comparison with healthy plantings), the number of insects and the size of the current dead trees; for episodic hotbeds, or hotbeds of mass reproduction, - a relatively short (3 to 5 years) period of development, a great number and size of the current dead trees. It has also been found that in both cases there are possible inverse and irreversible reactions of tree stands, although in the second scenario of the development of the population of pests, in the conditions of their mass reproduction, the full destruction of the forest plantation is most often observed. It was recorded that, near the hotbeds of mass reproduction, which are characterized by excessive population density, migration centers usually appear, where harmful insects migrate in search of new settlements.

scholarly journals Prognostication in plant protection. Review of the past, present and future of nonliner dynamics method

2020 ◽  
Vol 10 (4) ◽  
pp. 225-234
Author(s):  
S.V. Stankevych ◽  
Ye.M. Biletskyj ◽  
I.V. Zabrodina
Keyword(s):  
Solar Activity ◽  
Insect Pests ◽  
Chemical Elements ◽  
Plant Protection ◽  
Local Population ◽  
Reproduction Rate ◽  
The Sun ◽  
The Past ◽  
Mass Reproduction ◽  
Linear Differential

By carrying out a theoretical synthesis of the information on the regularities of population dynamics of some insect pests of agricultural plants and based on the past and present the authors have analysed the dynamics of many years in the number of the insect populations. An attempt to determine the presence of synchronism of outbreaks of the insects’ mass reproduction with the years of sharp changes in the solar activity has been made; the relationship between the changes in the number of the insects and meteorological and heliographic factors has been analysed. An analysis of the dynamics of the sun pest reproduction taking into account the duration of sunshine on the materials of one of the outbreaks (local population) in the Kupiansk district of the Kharkiv region showed the unreliability of this index as a predicate of the prognosis; and the reproduction rate of the local population of the sun pest does not change depending on the duration of the solar radiance. It is determined that this principle is also unsuitable for forecasting the dynamics in the number of this pest. The linear differential equations, in which not only the meteorological factors but also the indices of the solar activity (global factor) were used as variables were unsuitable for prognostication the dynamics in the number of the insects. The examples listed in the article confirm the fundamental regularity, namely the polycyclic dynamics of various natural systems and the synchronism in their development. The synchronization is inevitable because all objects of inanimate and living nature consist of the same chemical elements, and the conservation and conversion of energy is universal in nature. Based on the methodology of the cyclic dynamics it is possible to develop the algorithms for prognostication the regular mass reproduction of harmful insects.

scholarly journals Detecting Convective Overshoot In Solar-Type Stars

1993 ◽  
Vol 137 ◽  
pp. 557-559
Author(s):  
M.J. P. F. G. Monteiro ◽  
J. Christensen-Dalsgaard ◽  
M.J. Thompson
Keyword(s):  
Stellar Evolution ◽  
Practical Importance ◽  
Periodic Signal ◽  
Solar Mass ◽  
Simplified Models ◽  
Discontinuous Transition ◽  
Low Degree ◽  
Abrupt Changes ◽  
Solar Type ◽  
Convective Overshoot

It is important for understanding stellar evolution to constrain observationally how overshoot occurs for stellar conditions. Simplified models of the dynamics (eg. Zahn 1991) indicate that overshoot results in a slightly subadiabatic region beyond the convectively unstable layers, followed by an almost discontinuous transition to radiative stratification. Abrupt changes such as this contribute with a characteristic periodic signal to the frequencies ωn,l, of modes of low degree l (Gough 1990). This signature may therefore be detectable for distant stars. Here we show that the signal is sensitive to the “severity” of the overshoot and, of practical importance for the solar case, how it may be extracted from modes of higher degree. Finally we apply our method to solar data.To analyze the applicability of the method, we consider four stellar models, Z1 — Z4, with solar mass, radius (R) and luminosity; of these, Z2 and Z4 have overshoot. The bases of the nearly adiabatically stratified region in the models are at radii rd/R = .729, .713, .713 and .700 respectively.

PECULIARITIES CONDITIONS OF OCCURRENCE AND FORMATION OF DEFORMATION MEZOSTRUCTURES IN THE AREA OF KOBYLETSKA POLYANA VILLAGE (MARMOROSH MASSIF OF EASTERN CARPATHIANS)

2021 ◽  
pp. 116-126
Author(s):  
Viktor Alokhin ◽  
◽  
Alina Boiarska ◽  
Anna Мurovska ◽  
Valerii Ishkov ◽  
...  
Keyword(s):  
Microstructural Analysis ◽  
Research Area ◽  
Practical Significance ◽  
Eastern Carpathians ◽  
Abrupt Changes ◽  
History Of ◽  
Discontinuous Deformation ◽  
Micro Level ◽  
Structural Methods ◽  
Tectonic Movements

Purpose. The aim of the work was to establish the peculiarities of the conditions of occurrence and formation of deformation discontinuous mesostructures on the basis of field geological-structural and tectonophysical studies and microstructural analysis of rock samples. Methodology. The following are used in the work: traditional field geological and structural methods; methods of field tectonophysical research; computer programs «Fabric-8» and «Win-Tensor» for field data processing, construction of roses-diagrams of elements of discontinuous dislocations and reconstruction of paleostress field, mineralogical-petrographic and microstructural methods for studying the composition of rocks and microdeformations in sections. Results. According to the results of research, the systems of discontinuous deformation mesostructures and their correlation with regional discontinuous faults are established. The analysis of tectonic movements and their kinematic types is carried out, reconstruction of fields of paleonstresses is executed and features of changes of their types in different age deposits are established. The forms of manifestations of discontinuous dislocations at the micro level in sections are established. Scientific novelty. Several systems of discontinuous dislocation mesostructures have been established, which correspond to the main systems of regional discontinuous faults. Changes of their kinematic type in time are established for the same systems of discontinuous dislocations. Dislocations of the landslide type are a characteristic feature of the youngest sediments of the study area. Significant changes in the characteristics of paleostress fields on the research area have been established. Practical significance. The established peculiarities of the conditions of occurrence and evolution of discontinuous mesostructures in time allow to clarify the history of formation of the Marmorosh massif. It is established that the areas of intersection of discontinuous dislocations of different systems are the most promising for iron ore. Such areas are characterized by multistage in the development of discontinuous dislocations in time and abrupt changes in the kinematic types of paleostress fields. Key words: shales, limestones, sandstones, discontinuous deformations, landslides, mesostructures, paleostress field.

Assessment of the current state of the fresh groundwater resource base southern regions of the Komi Republic

2020 ◽  
Vol 10 ◽  
pp. 28-33
Author(s):  
Yu.A. Koksharova ◽  
Keyword(s):  
Research Area ◽  
Komi Republic ◽  
Groundwater Resource ◽  
Resource Base ◽  
Fresh Groundwater ◽  
Resource Potential ◽  
Underground Waters ◽  
Current State ◽  
Low Degree ◽  
Groundwater Reserves

The state of the resource base of fresh underground waters of the southern regions of the Komi Republic (RK) is assessed. The distribution of groundwater reserves by the administrative-territorial objects of the south of the Komi Republic, by geological and hydrogeological structures, by 83 explored deposits of drinking and industrial groundwater is analyzed. The volumes of groundwater production in 2019 are given. A low degree of development of the resource potential and groundwater reserves is noted. The degree of development of reserves does not exceed 6 %. The degree of knowledge of groundwater is 1 %. The aquifers (horizons) of fresh groundwater of the research area are characterized.

scholarly journals Wandering of Mass Reproduction of Harmful Insects Within the Natural Habitat

2019 ◽  
Vol 9 (4) ◽  
pp. 578-583
Author(s):  
S. V. Stankevych ◽  
H. V. Baidyk ◽  
I. P. Lezhenina ◽  
M. O. Filatov ◽  
V. I. Martynenko ◽  
...  
Keyword(s):  
Linear Systems ◽  
Insect Pests ◽  
Natural Habitat ◽  
Systems Dynamics ◽  
Winter Moth ◽  
Non Linear ◽  
Mass Reproduction ◽  
Insect Populations ◽  
Non Linear Systems ◽  
Development Paths

The wandering of non-linear systems along the field of the possible development paths is one of the important characteristics of dynamic non-linear systems in synergetics. Insect populations are a complex of open biological systems with chaotic non-linear dynamics in space and time. Predicting their future development is not an easy task. Ignorance of the non-linear systems dynamics regularity is the cause of the repeated errors in predicting and, as a result, “sudden” appearances of “unexpected” and unpredictable mass reproductions of short-horned grasshoppers and locusts, winter moth, webworm beetle, sun pest and some other insect pests, the consequences of that are catastrophic for agriculture and forestry. In this article the authors analysed thoroughly the chronicles of the mass reproduction (wandering within the temporal and spatial limits of the natural habitat) of such species as short-horned grasshoppers and locusts, webworm beetle and sun pest. These pests have been known to mankind since time immemorial and they are extremely devastating.

scholarly journals UNIVERSAL METHOD FOR COMPUTATIONAL MODELING OF THRESHOLD PHENOMENON IN THE NONSTEADY BIOLOGICAL PROCESSES

2021 ◽  
Vol 1 (1) ◽  
pp. 78-86
Author(s):  
A. Yu. Perevaryukha
Keyword(s):  
Computational Modeling ◽  
Hybrid System ◽  
Atlantic Cod ◽  
Insect Pests ◽  
Universal Method ◽  
Biological Resources ◽  
Threshold Phenomenon ◽  
Extreme Character ◽  
Abrupt Changes ◽  
Engraulis Ringens

Context. In modern conditions occur abrupt changes in ecosystems. The species composition of Caspian Sea is changing rapidly. The dynamics of populations acquires an extreme character with the development of rapid invasions. The mathematical description of scale transformations requires new modeling methods. Complicated population regimes of changes have features of the threshold phenomenon in process of its development. Objective. We set the goal of computational modeling of practically important scenarios – groups of situations that relate to extreme and transitional dynamics of ecosystems, like outbreaks at the onset of dangerous invasions. We are developing a method that, on the basis of the survival model of generations, will conduct a description of sudden transitions to rapid but limited outbreak of numbers or, on contrary, a collapse of stocks like Atlantic cod in 1992 or Peruan anchovy Engraulis ringens in 1985. The purpose of our modeling is to improve the accuracy of forecasts of the population size when experts are estimates a rational strategy for the exploitation of biological resources. Method. Situations of abrupt but short-term changes in population processes cannot be calculated by traditional mathematical models and expressed in terms of asymptotic dynamics – closed limit trajectory sets. The basis of the idea of the method proposed by us is the formalization of nonlinear efficiency of reproduction, which changes in a threshold manner only in strictly defined environmental conditions. We use continuous-discrete time in the model for early ontognosis of the cod fish and insect pests. The method with triggers allows us to take into account in simulation experiments logic and motivation of making decisions by experts, people who manage the strategy of exploiting biological resources. Models assess variability for development of situations Results. We have implemented new method of bounded trigger functionals into hybrid system of the equations, that acting in selected specific states of biosystems. Analysis of new model scenarios with modifications of functionals in the basic hybrid system for extreme situations in fish and insect pests is carried out. Conclusions. We consider the method to be universal, since selection of the functional can be adapted to a wide class of models using differential equations on a fixed interval.

scholarly journals Історія, закономірності та прогнозування масового розмноження основних видів шкідників капусти в Лівобережному Лісостепу України

2013 ◽  
pp. 155-157
Author(s):  
С. В. Пономаренко
Keyword(s):  
Retrospective Analysis ◽  
Historical Data ◽  
Insect Pests ◽  
Ecological Factors ◽  
Forest Steppe ◽  
Left Bank ◽  
High Quality ◽  
Mass Reproduction ◽  
Cabbage Pests ◽  
Sun Activity

Проаналізовано сучасні погляди на можливість використання екологічних чинників (сонячної активності) для прогнозування масового розмноження популяцій комах-шкідників на прикладі основних шкідників капусти в умовах Лівобережного Лісостепу України. Враховуючи актуальність прогнозування масового розмноження основних листогризучих шкідників капусти з ряду лускокрилих (совки капустяної (Mamestra brassicacea L.), білана капустяного (Pieris brassicacea L.), виконано ретроспективний аналіз історичних даних про масові розмноження останніх у просторі й часі та розроблено якісний прогноз їх появи на територіїПолтавської області. Modern looks to possibility of the use of ecological factors (sun activity) for prognostication of mass reproduction of populations of insect pests on the example of basic cabbage pests in the conditions of Left-bank Forest-steppe of Ukraine are analysed. Taking into account actuality of prognostication of mass reproductions of basic leaf-eating pests of cabbage from the order of Lepidoptera (Mamestra brassicacea L., Pieris brassicacea L.), the retrospective analysis of historical data about mass reproductions of the latter in space and time is done and the high-quality prognosis of their appearance on territory of the Poltava area is developed.

scholarly journals The Dominance of physico-morphic plant traits in regulating population density of Bemisia tabaci and Thrips tabaci in Bt and non-Bt Cotton

1970 ◽  
pp. 28-32
Author(s):  
Mirza Abdul Qayyum, Muhammad Asad Saleem, Muhammad Ishtiaq ◽  
Ghulam Murtaza, Saif Ullah, Aboubakar Siddique
Keyword(s):  
Bemisia Tabaci ◽  
Negative Correlation ◽  
Plant Traits ◽  
Insect Pests ◽  
Research Area ◽  
Climatic Conditions ◽  
Thrips Tabaci ◽  
Maximum Temperature ◽  
Bt Cotton ◽  
Weather Factors

Policy makers, journalists and other commentators often advocate transgenic cotton (Gossypium spp.) as poor-performer against sucking insects that pose a great threat to production targets. A field study was carried out for seasonal occurrence of whitefly (Bemisia tabaci Gennadius) and thrips (Thrips tabaci Lindeman) on two of cotton genotypes namely Bt MNH-992 and non-Bt Cyto-124 under climatic conditions of Multan, Pakistan from July-October, 2017. Impact of environment as a factor was hypothesized on pests on two experimental sites [Research Area (RA) & Farmer Field (FF)]. Maximum population of whitefly at RA (13.5 and 16.7 individuals per plant) for Bt and non-Bt, respectively was recorded during SMW 40, while correspondent minimum populations (0.6 & 1.2 individuals per plant) was found during SMW28 in RA. The peak population of thrips was observed at RA during 30th SMW as (4.9 & 8.9 individuals per plant), respectively at Bt and non-Bt genotypes, declined to the lowest level of (0.1 & 0.3 individuals) in 41st SMW for both genotypes. Bt-cotton harbored relatively lower population of B. tabaci and T. tabaci in both fields owning to the presence of physico-morphich plant characters. A negative correlation of B. tabaci population was found with a maximum temperature and rainfall, and a positive relation with humidity. T. tabaci had a positive correlation with temperature and rainfall, and a negative correlation with relative humidity. The current research concluded that weather factors play and important role to increase or decrease the populations of sucking insect pests of cotton.

scholarly journals Prognostication algorithms and predictability ranges of mass reproduction of harmful insects according to the method of nonliner dynamics

2020 ◽  
Vol 10 (1) ◽  
pp. 37-42
Author(s):  
S. V. Stankevych ◽  
Ye. M. Biletskyj ◽  
I. V. Zabrodina ◽  
M. D. Yevtushenko ◽  
H. V. Baidyk ◽  
...  
Keyword(s):  
Nonlinear Dynamics ◽  
Insect Pests ◽  
Plant Protection ◽  
Evolutionary Process ◽  
Point Of View ◽  
Optimal Decision ◽  
Theoretical Synthesis ◽  
Breeding Grounds ◽  
Mass Reproduction ◽  
The Many

The authors have analysed the theoretical possibilities of prognostication the dynamics in the number and mass reproduction of some species of harmful insects. A theoretical synthesis of the information on the regularities of the population dynamics of the most common insect pests of agricultural plants from the point of view of the methodology of nonlinear dynamics and synergetics has been done. Based on the past and present an analysis of the many-year dynamics in the number of the insect populations has been carried out and an attempt to develop the algorithms for prognostication the seasonal and annual changes in the number of the insects has been made. To do this the authors recommend a scenario-based method of prognostication and making decisions in plant protection. Using the phytosanitary monitoring they determine the beginning of the regular mass reproduction (the appearance of an aggravated rate) and then, based on the phytosanitary prognosis, an aggravation of the situation that has developed or is being developing on the farm, in the district or in the region is made; after that on the base of the short-term prognosis (signaling) it is recommended to make the optimal decision to protect a particular crop taking into account the economic threshold of harmfulness. According to the authors this approach, based on the methodology of nonlinear dynamics (synergetic paradigm), makes it possible to determine in advance the breeding grounds of the aggravated rates and make the optimal decisions in plant protection. The predicted scenario will not be a prognostication of the future, but the elements of an evolutionary process inherent in nature.

scholarly journals Assessment of the volume of harvested wood in accordance with the vital state of wood species

2021 ◽  
Vol 875 (1) ◽  
pp. 012077
Author(s):  
I Konovalova ◽  
E Lelekova
Keyword(s):  
Dead Wood ◽  
Insect Pests ◽  
Vital Activity ◽  
Main Criterion ◽  
Deciduous Species ◽  
Peripheral Part ◽  
Dead Trees ◽  
Vital State ◽  
Forest Users ◽  
Species Specific

Abstract During selective felling on the territory of 3.9 ha, 181 m3 of wood, 35% of which is dead wood. Among them, pine (16 m3), spruce (27 m3), birch (8 m3) and aspen (12 m3) were found. The volume of cut viable wood was 118 m3, including 50 m3 of pine, 44 m3 of spruce, 14m 3 of birch and 10 m3 of aspen. The values obtained do not exceed the forest declaration data. To determine the stumps from dead coniferous trees, the following criteria were tested: complete or partial absence of bark, the presence of traces of the vital activity of insect pests and abundance worm dust. Species-specific criteria are proposed: in pine – the presence of rot of the peripheral part of the wood, brown color of sapwood and bast; spruce – the presence of heart rot and wood destroying fungi. In deciduous species, the main criterion for isolating stumps from dead trees has been tested – the presence of wood-destroying fungi, in aspen – heart rot caused by tinder fungi. We recommend using these criteria to resolve legal claims against forest users in the removal and assessment of harvested wood.

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