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Ecological Structure of the Harmful Entomocomplex of Apple Orchards of the Central Forest-Steppe of Ukraine

Mostoviak Svitlana, Berezovskyi Andrii, Krykunov Ihor

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

155--162

EN

The most widespread culture in the structure of fruit plantations in Ukraine is the apple tree. An important factor in the highly efficient production of apples is ensuring proper phytosanitary state of plantations and observing agrotechnological methods of growing, which is possible only with constant and long-term monitoring of the species composition, population dynamics, biological and ecological features of the entomoplex. The aim of the study conducted in 2005–2020 was to determine the ecological structure of the harmful entomocomplex of apple orchards under the conditions of the Central Forest-Steppe of Ukraine. Field, laboratory and chamber research methods generally accepted in ecology and entomology were used to fulfill the tasks. In the study, 52 species of phytophagous insects from 25 families and 7 orders were identified; 5 species of phytophagous mites from 3 families of Tetranychidae (Panonychus ulmi Koch., Tetranychus urticae Koch., Scizotetranychus pruni Oudms.), Bryobiidae (Bryobia redikorzevi Reck., syn: Bryobia praetiosa Koch.), Eriophyoidae (Eriophyes mali Nal.) were also found. The taxonomic structure of phytophagous insects was dominated by representatives of the orders of Lepidoptera (24 species), Coleoptera (14 species) and Homoptera (9 species), the portion of which collectively amounted to 90%. A range of Lepidoptera represented by 13 families was characterized by wide species diversity: Tortricidae, Gracillariіdae, Yponomeutidae, Lyonetiidae, Cossidae, Sesiidae, Coleophoridae, Lasiocampidae, Geometridae, Pieridae, Arctiidae, Noctuidae, Orgyidae, which accounted for 46% of the harmful entomocomplex. The most numerous (dominant) species for the period 2005-2020 were three species of aphids (Aphis pomi De G, Dysaphis devecta Walk, Dysaphis mali Ferr.), apple moth (Carpocapsa pomonella L.) and leaf rollers (Archips rosana L.). In terms of trophic specialization, polyphages dominated 75% (39 species) of apple tree agrocenoses, 10% (5 species) of oligophagous insects, 15% (8 species) – monophages. The life forms were dominated by phytophiles – dendrobiotes, the percentage of which in the total structure of insect pests was about 90%. The species composition of harmful entomofauna and ecologically constant species of phytophagous insects in apple plantations in the Central Forest-Steppe of Ukraine were specified. A promising study is to clarify the features of the biology of the most harmful phytophagous insects under the conditions of climate change and to develop environmentally safe means of protecting apple plantations from pests.

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Effects of human activities in the coastal zone of Laizhou Bay

Wang Min, Han Mei, Hui Hongkuan, Li Yunlong

Ecological Chemistry and Engineering. S

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2021

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Vol. 28, nr 2

219--227

EN

The serious destruction of resources and environment in Laizhou Bay has attracted extensive attention of researchers. This study mainly analysed the changes of fish structure and environment in the coastal zone of Laizhou Bay caused by human activities. By consulting literatures and field measurements, the changes of dominant fish species, coastline and sea water intrusion were analysed. The results showed that dominant fish species in Laizhou Bay change from high-economic species to low-economic species under the influence of human activities, and the coastline erosion was serious, and the area of sea water intrusion was also increasing year by year. It is concluded from the research results that human activities had a significant impact on the structure of fish school and the environment. It is necessary to arrange human activities in an appropriate amount to reduce the overexploitation of resources in order to restore the fishery resources and environment in Laizhou Bay.

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Grazing Exclusion Effects on the Relationship between Species Richness and Vegetation Cover in Mongolian Grasslands

Guo Tong

Polish Journal of Ecology

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2020

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Vol. 68, nr 3

211--228

EN

Understanding the role of plant diversity in maintaining vegetation cover is a central focus of assessing the vegetation dynamics of grasslands. The present study assessed the relationship between species richness and vegetation cover, as well as underlying biological mechanisms in three Mongolian grasslands, namely meadow, dry steppe and mountain steppe. Each of three grasslands was set by two treatments: grazing exclusion by fence and freely grazing. I measured plant species richness, vegetation cover, height and phenology. I examined three biological mechanisms, namely plant interactions, the role of dominant species and vegetation growth periods. The results showed that higher species richness generally increased vegetation cover independent of fencing treatment and grassland type. Plant interactions were the strongest in fenced plots of the mountain steppe. Dominant plant species invested more in vegetation cover rather than the height in grazed plots than fenced ones in Mongolian grasslands. Taking vegetation growth periods into account did not alter the strength and the direction of the relationship between species richness and vegetation cover. I thus infer that examining changes in species diversity will allow for a better understanding of vegetation cover dynamics in grasslands. This will help to assess how ecosystem functioning might be impacted by grazing disturbances in Mongolia.

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Adaptative strategy of leaf traits to drought conditions: Quercus aliena var. acuteserrata forest (The Qinling Mts. China)

Wang M., Wan P., Chai Y., Guo Y., Zhang X., Yue M.

Polish Journal of Ecology

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2015

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Vol. 63, nr 1

77--87

EN

In a climax community where all species are sharing relatively similar and stable habitat, there are differences in leaf traits between deciduous trees and shrubs and dominant species and companion species, especially in leaf lifespan (LLs). What are the differences of relationships among leaf traits between deciduous trees and shrubs? What are the mechanisms of this phenomenon? Here, we presented a one-year observation and recorded the LLs followed a modified method in a Quercus aliena var. acuteserrata forest in the north slope of the Qinling Mountains, China. We found that (i) Different species in the same stand performed quite differently in their LLs (P <0.005). Average LLs of shrubs was slightly longer (P = 0.05) than that of deciduous trees. (ii) LLs showed a significant negative correlation with specific leaf area (SLA) and leaf nitrogen content (LNC) (P <0.05) in deciduous trees, however, a significant positive correlation with LNC and leaf carbon content (LCC) (P <0.05) was detected in shrubs. (iii) The comparison of the traits between dominant and companion species in arbor layer and shrub layer showed that there was no significant difference in LLs, LCC and LNC, except SLA in arbor layer. Our study indicated that the amount of light, at the community scale, might be a main factor determining the LLs of wood plants in deciduous forest. The difference between trees and shrubs in relationships among leaf traits suggests that deciduous trees and shrubs may take different strategies to adapt to the environment. SLA is likely to be a marker trait to distinguish dominant and companion species in arbor layer of deciduous broad leaved forest

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Leaf morphology shift of three dominant species along altitudinal gradient in an alpine meadow of the Quinghai â Tibetan Plateau

Zhong M., Wang J., Liu K., Wu R., Liu Y., Wei X., Pan D., Shao X.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

639--648

EN

It has been observed that leaf morphology shift within species is linked to climate change, but there are few studies on the effects of altitude change on leaf morphology of species. We hypothesized that similar to climate change, a morphological shift within species would occur over time under different growing altitudes. In this study, we evaluated three dominant grass species: Elymus nutans Griseb., Kobresia capillifolia Clarke., Carex moorcroftii Boott., taking advantage of the altitudinal variations (3000-4000 a.s.l.) on the Qinghai-Tibetan Plateau. Our study showed that almost all leaf traits of these three species had significant differences (P <0.05) across an altitudinal gradient. Different species responded differently to altitude change. Leaf thickness (LT) of the three species increased with increase in altitude. Leaf area (LA) of E. nutans and C. moorcroftii decreased with increasing altitude, but that of K. capillifolia increased. There was no obvious linear effect on leaf dry matter content (LDMC) and specific leaf area (SLA) of these three species. LDMC of E. nutans and C. moorcroftii showed a trend of increase, while that of K. capillifolia decreased. SLA of E. nutans and K. capillifolia showed a trend of increase, but that of C. moorcroftii decreased with increase in altitude. In addition, soil pH (pH) and air temperature (AT) decreased with increase in altitude. However, other soil and climate factors increased as altitude increased. The finding of this work is that leaf morphology shift within species happens under altitude change to adapt to specific environment.

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Spatial and seasonal variations of large tintinnid ciliates in Shenhu Bay of China

Wang Y., Zhang W., Lin Y., Zheng L., Cao W., Yang J.

Oceanological and Hydrobiological Studies

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2014

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Vol. 43, No. 3

292--302

EN

In this study, the spatial distribution and seasonal variation of large tintinnids (>76 μm) were investigated in Shenhu Bay during three seasons of 2012. Of the 36 species identified, 9 were dominant (i.e. Tintinnopsis radix, Leprotintinnus simplex, Tintinnopsis japonica, Tintinnopsis tubulosoides, Leprotintinnus nordqvisti, Tintinnopsis beroidea, Stenosemella parvicollis, Tintinnidium primitivum, Tintinnopsis nana). A clear seasonal shift of the taxonomic composition as well as the lorica size of the dominant species was observed. The highest numbers of tintinnid species occurred in spring, while the highest abundance and biomass occurred in summer. Clustering indicated that the seasonal variations of the community structure were more obvious than spatial variations. Spearman correlation analysis revealed that density of phytoplankton prey had a significant impact on the tintinnid abundance. Redundancy analysis (RDA) illustrated that temperature, salinity and the nutrient level were the most important abiotic factors affecting the spatial and seasonal pattern of tintinnid communities in Shenhu Bay.

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Trophic state assessment based on late summer phytoplankton community structure: a case study for epilimnetic lake water

Szeląg-Wasielewska E.

Oceanological and Hydrobiological Studies

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2007

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Vol. 36, No.3

53-63

EN

Phytoplankton species composition, abundance and biomass were studied in samples taken from the epilimnion of Lake Strzeszyńskie in late August of each year from 2000-2005. The number of phytoplankton species was relatively low, with the greatest species diversity observed in the Chlorophyceae. Total phytoplankton abundance was high, with major contributions by picophytoplanktonic cyanobacteria, which formed aggregations. Total phytoplankton biomass was generally low, with the sum of the 2-5 biomass-dominant species always exceeding 50% of the total phytoplankton biomass. The taxonomic composition of the group of biomass dominants was relatively stable inter-annually. On the basis of phytoplankton biomass and chlorophyll a concentration, Lake Strzeszyńskie can be classified as oligo-mesotrophic and mesotrophic respectively. Trophic index values calculated on the basis of abundance of phytoplankton indicator taxa were higher than the values based on their biomass, and mean values indicate that the lake is mesotrophic or intermediate between mesotrophic and eutrophic.

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Vertical distribution of dominant cyanobacteria species in three lakes - evidence of tolerance to different turbulence and oxygen conditions

Wojciechowska W., Poniewozik M., Pasztaleniec A.

Polish Journal of Ecology

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2004

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Vol. 52, nr 3

347-351

EN

The composition and abundance of cyanobacteria in three lakes of the Polesie Lubelskie (East Poland) were studied in summer periods. Vertical distribution of these algae was analysed in two depths - in epilimnion and deoxygenated metalimnion. Species composition and domination was similar for these two sites. It means that the species like: Limnothrix planctonica (Wołosz.) Meffert, Limnothrix redekei (Van Goor) Meffert, Planktothrixs agardhii (Gom.) Anagn. et Kom., Woronichinianaegeliana (Unger) Elenk. and Microcystis viridis (A. Braun in Rabenhorst) Lemm. are not affected by turbulence of water as well as by oxygen conditions.