scholarly journals The Lessons of Scots Pine Forest Decline in Ukraine

2020 ◽  
Vol 3 (1) ◽  
pp. 28
Author(s):  
Valentyna Meshkova

The condition of Ukraine’s forests has deteriorated sharply since the 2009 drought. The area of Scots pine stands decline has increased 2.3 times. The purpose of the research is integrating published and own data on Scots pine forest decline with the contribution of bark beetles and pointing the ways for mitigating this process. The reference materials regarding the forest stands characteristics, forest health, weather, as well as the results of own field and laboratory research were the data sources. Ips acuminatus (Gyllenhal, 1827): Coleoptera: Curculionidae: Scolytinae was the first bark beetle to infest weakened stands. The predominant development Scots pine decline in Polesie (Forest zone) is associated with a large proportion of pure pine stands of the same age, untimely thinning, and relatively slow drying of felling residues, in which the bark beetle has time to complete its development. The relative density of stocking by itself is a less important risk factor than its sudden decrease. The algorithm for prediction of bark beetles’ foci spread was developed. It will help to upgrade the accuracy of prediction, to evaluate the area of survey and control measures against insect pests. Recommendations for improving the forestry regulatory framework have been developed.

Author(s):  
В.Л. Мешкова

Цель исследования обобщение опубликованных материалов и собственных данных об условиях возникновения очагов усыхания сосновых лесов и возможностях минимизации негативных последствий. Источники данных справочные материалы по структуре лесного фонда лесохозяйственных предприятий, состоянию лесов, характеристики погодных условий, результаты собственных полевых и лабораторных исследований (обследований насаждений, лабораторного выращивания короедов в отрезках ветвей, расчета популяционных показателей). За последние десятилетия изменились показатели тепла, влаги и континентальности, характеризующие лесоклиматические зоны, что влияет на состояние лесов и их восприимчивость к заселению короедами. Возрастание значения короедов рода Ips в комплексе стволовых вредителей сосновых лесов Украины связано с их поливольтинностью. Жуки отдельных поколений и фенологических групп вершинного короеда (Ips acuminatus) заселяют ослабленные деревья, ветровал и порубочные остатки в течение значительной части вегетационного периода. Доказана возможность развития трех поколений вершинного короеда в году в Харьковской области, однако быстрое высыхание порубочных остатков с повышением температуры может препятствовать завершению развития вредителя. Медленное высыхание заготовленной древесины и порубочных остатков в Полесье стало важной причиной интенсивного развития вспышек короедов в этом регионе. Предложено оценивать потенциальную площадь очагов усыхания в областях или природных зонах с учетом доли чистых сосновых насаждений и их возраста, а на уровне лесных массивов учитывать соседство выделов с вырубками. Отмечено несовершенство нормативной базы лесного хозяйства, препятствующее заготовке древесины в очагах короедного усыхания до того, как она превратится в дровяную. The goal of the research was integration of published and own data on the conditions for the occurrence of foci of pine forest decline and the prospects for mitigating this process. The data were obtained from reference materials on forest fund structure in forest enterprises, forest health, weather conditions, and the results of own field and laboratory research (forest inspections, laboratory rearing of the bark beetles in branches, and evaluation of population parameters). The main parameters of the forest climatic zones (heat, humidity, and continentality) have changed during the last decades. This affects forests health and their susceptibility to bark beetle colonization. The increase in the impact of Ips genus bark beetles in the complex of stem pests in pine forests of Ukraine is pertinent to their multivoltine development. Beetles of certain generations and phenological groups of pine engraver beetle (Ips acuminatus) colonize weakened and windthrown trees and logging residues during considerable part of vegetation period. A possibility of development of three generations per year has been proven for Ips acuminatus in Kharkov region (foreststeppe zone). However, quick drying of logging residues combined with increasing temperature may prevent the completion of pests development. Slow drying of harvested wood and logging residues in Polesie was an important reason for the intensive development of bark beetle outbreaks in the region. It was suggested to evaluate a potential area of drying forest in the regions or natural zones with consideration of the proportion of pure pine stands and their age. For certain forest stands, the proximity of every plot to clearcuts of the last two years must be taken into account. The flaws of forestry regulatory legislation are noted. These flaws prevent timely harvesting of timber in the bark beetles foci before this timber turns into firewood.


2020 ◽  
Vol 47 (2) ◽  
pp. 81-88
Author(s):  
Peter Zach ◽  
Milada Holecová ◽  
Marek Brabec ◽  
Katarína Hollá ◽  
Miroslava Šebestová ◽  
...  

AbstractUnderstanding of habitat favourability has wide relevance to the invasion biology of alien species. We studied the seasonal dynamics of the alien ladybird Harmonia axyridis (Coleoptera: Coccinellidae) in monoculture Scots pine forest stands in south-west Slovakia, Central Europe, from April 2013 to March 2015. Adult H. axyridis were collected monthly across seven randomly selected pine stands of different ages and canopy closure, from the lower branches of pine trees, and larvae were recorded qualitatively. Adults were recorded all year round, most abundantly in November and least abundantly in February. The relationship between the abundance of H. axyridis and selected forest stand characteristics was modelled using the negative binomial Generalized Additive Model with penalized spline component in month (seasonality) effect, year, canopy closure and age effects and the random effect of forest stand (sample area effect). The abundance of H. axyridis was significantly influenced by the age of stand and seasonality (with month granularity) for both closed and open canopy stands, whereas the effects of canopy closure and sample area were not significant. The bimodal pattern of seasonal dynamics of H. axyridis on Scots pine was common for closed and open canopy stands, with two peaks reflecting the cyclic movement of the species from and to overwintering sites. Harmonia axyridis utilized certain pine stands preferably for foraging during the growing season and certain stands for refuge during winter. The ladybirds were found in highest numbers in the 15 year old closed canopy stand (overwintering site). The occurrence of both adults and larvae in most stands indicated a suitability of Scots pine forest for ladybird breeding. The model of year-round dynamics of H. axyridis has been presented for the first time within the invaded range of the ladybird in Europe.


1988 ◽  
Vol 53 ◽  
Author(s):  
C. De Schepper

The  study describes the natural regeneration state of a forest on coarse sandy  soils. The natural regeneration was studied in three different ecological  conditions: in 30 to 60 year old Scots pine stands, in a 62 year old mixed  stand of pedunculate oak and red oak, and on the free field.     The analysis of the regeneration groups revealed that the first settler  maintained a dominant social position during the following years after the  settlement. The structural basis is consequently laid out early. This means  that the forest practice has to consider the very first phase of the  regeneration as determining for the following evolution of the regeneration  groups.


1988 ◽  
Vol 53 ◽  
Author(s):  
N. Lust

The  study deals with the spontaneous resettlement of a fire area, after  destruction of 600 ha Scots pine forest. The following items have been  examined in particular: the composition of the tree species, the duration of  the regeneration period, the influence of the parent stand, the exposition,  the slope, the treatment, the fire regime and the social differentiation.      The resettlement took place very quickly and over a very short period.  Birch and Scots pine take up 95 % of the stem number. The regeneration result  is precarious, yet mostly good. The parent stand is favourable both to seed  supply and to microclimate, but only over a short distance. The Scots pine  prefers more open and dry areas, whereas birch needs more humidity.     Practice has shown that natural regeneration of Scots pine stands is  possible. The forest treatment, however, is very important. It determines not  only the immediate result of the regeneration, but also the composition and  the structure of the future stand.


2002 ◽  
Vol 167 (1-3) ◽  
pp. 123-134 ◽  
Author(s):  
K Butterbach-Bahl ◽  
L Breuer ◽  
R Gasche ◽  
G Willibald ◽  
H Papen

Author(s):  
Kateryna Davydenko

Pine bark beetles are typically associated with complexes of fungi that could reveal different functional interaction. Thus, previously nonaggressive bark beetle Ips acuminatus is considering now to be among the most serious pests of pine forest in Ukraine and other European countries and vectored fungal community is very important to assess total harm of this bark beetle. The aim of this study was to reveal the vectored fungal community associated with the pine engraver beetle, I. acuminatus with special emphasis on pathogenic fungi for further evaluation of harm bark-beetle - fungi association for Ukrainian forest. In total, 288 adult beetles were collected from Scots pine trees at six different sites through Ukraine. DNA sequencing as fungal culturing from all beetles resulted in 1681 isolates and amplicons representing 42 fungal taxa. NCBI BLAST search revealed that the overall fungal community was composed of 94 species, of which 80.85% were Ascomycota, followed by Basidiomycota and unidentified fungal group, which accounted for 10.6% and 8.5 % of the total sequences, respectively. Among these, the most commonly detected fungi for pooling dataset were Sphaeropsis sapinea (23.6%), Cladosporium pini-ponderosae (19.44%), Ophiostoma ips (19.1%), Ophiostoma canum (19.1%) and Cladobotryum mycophilum (18.06%). In the pooled dataset of isolates and amplicons for each site, Shannon diversity indices ranged between 1.9 and 2.9 while Simpson diversity index varied between 0.69 and 0.89 indicating rich species diversity. In total twelve ophiostomatoid species were detected. All ophiostomatoid fungi were showing varying degrees of virulence and O. minus was the most aggressive fungus in previous studies. It is concluded that I. acuminatus vectors a species-rich fungal community including pathogens such as ophiostomatoid fungi, Sphaeropsis sapinea, different needle pathogens and wood decay fungi that seems to be very important for the assessment of threat of I. acuminatus to the pine forest in Ukraine.


Author(s):  
Valentyna Meshkova ◽  
Ivan Bobrov

Outbreaks of bark beetles have increased in recent years in various regions. Pine engraver beetle (Ips acuminatus (Gyllenhal, 1827); Coleoptera: Curculionidae: Scolytinae) is most common in the pine forests of many European countries. Research on its biology and spread carried out in different natural conditions, phases of pest outbreak and considered various parameters to characterize the population of the pest and forest health condition. The aim of the research was to compare the health condition of Scots pine stands and population parameters of I. acuminatus in its two generations in pure and mixed stands in Polissya and Forest-steppe parts of Sumy region. Research was carried out in 2017 in the pure Scots pine stands and mixed stands with Scots pine and other forest species in Polissya (State Enterprise "Seredyno-Budsky Agroforest Economy"; State Enterprise "Seredyno-Budsky Forest Economy") and Forest-steppe parts (State Enterprise "Velykopysarivske Agroforest Economy"; State Enterprise "Okhtyrske Forest Economy") of Sumy region at 26 sample plots. In sample plots, parameters of forest health condition and bark beetle population were assessed in June and in September, after completion of development of spring and summer generation of I. acuminatus.  By most of the parameters assessed, significant differences between sample plots in Forest-Steppe and Polissya parts of Sumy region were not found. In pure Scots pine stands the mean area of bark beetles’ foci and bark beetles’ production were larger in Forest-steppe in June, and the density of Ips acuminatus nuptial chambers in June and September. In pure Scots pine stands the area of I. acuminatus focus, the number of colonized trees, the proportion of recently died trees, health condition indices, the density of egg galleries and nuptial chambers as well as young beetle’s production increased from June to September. In mixed stands the focus area, the number of colonized trees and health condition index increased insignificantly, and population parameters of I. acuminatus decreased from June to September. Pure Scots pine stands changed the health condition from "severely weakened" to "drying up" in three months, and mixed ones remained in the "weakened" category. In pure pine stands, the density of egg galleries and beetles of the young generation increased for three months from the lower limit of a moderate level to a high level, the density of nuptial chambers – from low to a high level. In mixed stands, all population parameters of I. acuminatus correspond to a low population level. The parameters characterizing the investigated foci of I. acuminatus in the Sumy region significantly correlated with the participation of pine in the stand composition, and in September the correlation is closer than in June. The data obtained indicate the feasibility of creating predominantly mixed pine stands.


2008 ◽  
Vol 148 (11) ◽  
pp. 1815-1826 ◽  
Author(s):  
Jutta Holst ◽  
Romain Barnard ◽  
Elke Brandes ◽  
Nina Buchmann ◽  
Arthur Gessler ◽  
...  

1992 ◽  
Vol 23 (13-14) ◽  
pp. 1575-1589 ◽  
Author(s):  
A. P. Rowland ◽  
A. F. Harrison ◽  
V. H. Kennedy ◽  
J. N. Cape

2001 ◽  
Vol 65 (6) ◽  
pp. 1812-1823 ◽  
Author(s):  
Live S. Vestgarden ◽  
Gunnar Abrahamsen ◽  
Arne O. Stuanes

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