Ecological features of terrestrial insect fauna of the botanical garden of Vasyl Stefanyk Precarpathian national university

The main purpose of the research we conducted in June-September 2018 was to study the features of the terrestrial entomofauna of the botanical garden of VasylStefanykPrecarpathian National University, in areas with different anthropogenic loads. For this purpose, we chose three biotopes: the area near the pond (one sample plot), forest (two sample plots) and meadow-steppe ecosystems (three sample plots).

Experimental area 1 - site near the pond - 48°56'33.1”N 24°40'42.4”E;

Experimental area 2 - meadow-steppe ecosystem - 48°56'29.6”N 24°40'30.1”E;

Experimental area 3 - meadow-steppe ecosystem - 48°56'23.7"N 24°40'12.2”E;

Experimental area 4 - forest - 48°56'43.8”N 24°40'04.1”E;

Experimental area 5 - forest - 48°56'43.1”N 24°39'57.5"E;

Experimental area 6 - meadow-steppe ecosystem - 48°56'35.4”N 24°39'50.2”E (see on the map).

Terrestrial insects were caught in the experimental areas. The species composition of the entomofauna was determined with the help of identifiers and scientific articles in the zoological museum of the department biology and ecology.

The results of catches using various traps were used to determine the number of insect populations. For the quantitative assessment of biological diversity, a large number of indices of varying degrees of complexity are used, which allow an objective assessment of the state of communities and ecosystems. We calculated four indices characterizing biodiversity: Shannon, Menkhinik, Simpson and BergerParker [4, 6, 7].

Fig. 1. Map of the botanical garden of VasylStefanykPrecarpathian National University

Research results and their discussion

We discovered 54 species of insects during the research in June-September 2018 (Table 1). The analysis of the species composition showed that the terrestrial insect fauna in the botanical garden is mainly represented by beetles from two families - Ground beetle (CarabidaeLatreille, 1802) and Darkling beetle (TenebrionidaeLatreille, 1802).

Tab.l.The relative abundance of terrestrial insects in the botanical garden of Vasyl Stefanyk Precarpathian National University (2018, insects/100m²)

On the site near the pond and two experimental areas in forest, 68 insects/100m2 of Ground beetle were found in June-July, in August-September the number of Ground beetles increased sharply - up to 330 insects/100m2. 148 insects/100m2 were found in the meadow-steppe plots (3 research areas) in June- July, and 237 insects/100m2 in August-September. The increase in number of Ground beetle in the experimental territories in August-September can be explained by their mass reproduction and activation of their physiological processes.

The following species of Ground beetle were most abundant in the area near the pond and in two forest areas: Amara aulica, Ophonusrufipes, Calathusambiguus and Calathuserratus. The following species of Ground beetle were not found at all in these research areas: Harpalusamplucalis, Taphoxemagigas, Pterostichusmacer, Amara equestris, Amara convexiuscula and Amara pastica.

The following species of Ground beetle were the most common in the meadow-steppe areas: Amara aulica, Amara bifrons, Amara equestris, Ophonusrufipes, Calathusambiguus and Calathuserratus. The following species of Ground beetle were not found at all in these research areas: Amara ingenue, Ophonusazureus, Pterostichuspunctulatus, Harpaluszabroides, Harpalusdistringuendus, Harpalusrubripes, Cymindusangularis, Notiophiluspalustris, Syntonus sp., Microlestes sp. and larvae.

In the experimental plots, the number of Ground beetle, mostly of all species, was quite low, only in August-September, a mass appearance of Calathusambiguus, Calathuserratus was observed in all experimental areas.

In the area near the pond and two experimental plots in forest, 92 insects/100m2 Darkling beetle were found in June-July, in August-September the number of Darkling beetle decreased sharply - to 2 insects/100m2. 86 insects/100m2 were found in the meadow-steppe area (three research areas) in June- July, and 29 insects/100m2 in August-September. The decrease in the number of Darkling beetle in the experimental areas in August-September can be explained by their mass destruction due to their ability to damage field plantings, because the country estate is located next to the botanical garden. The country estate and human settlements are located closer to experimental plots 1, 4 and 5, therefore, in these areas too, we observe a mass death of Darkling beetle in August-September.

The followingDarklingbeetlespeciesweremost abundant in theareanearthepond and in twoforest areas: Blapshalophila, Opatrumsabulosum and Oodoscelispolita. The following species of Darkling beetle: Crypticusquisquilius, Pedinusfemoraliswere not found at all in these research areas.

The most common species in the meadow-steppe areas were all species of Darkling beetle, which are common in the study area, except for Crypticusquisquilius and Pedinusfemoralis.

In the experimental areas, thenumber ofDarklingbeetle, mostly of all species, was quitehigh in June-July, except for Crypticusquisquilius and Pedinusfemoralis, which were observed only in the meadow-steppe areas of the botanical garden, and in August-September, a decrease in the number of Darkling beetle was observed in the experimental areas near the pond and in the plots in the forest, and in the meadow-steppe research plots of the botanical garden were quite common.

On the area near the pond and two experimental sites in forest, no one individual of the order Orthoptera was not found in June-July, in August-September their number was 35 insects/100m2. In the meadow-steppe area (three research areas) 2 insects/100m2 were found in June-July, and 26 insects/100m2 in August-September. The increase in the number of representatives of the order Orthoptera can be explained by their massive reproduction and development during this period.

The following species order Orthoptera were most abundant in the area near the pond and in two forest areas: Oedipodacaerulescens, Chorthippusbiguttulus, Chorthippusmacrocerus. The following orthopteran species: Calliptamusitalicus, locust larvae, and Ovocestushaemorrhoidalis were not found at all in these research areas.

The following species of Orthoptera were most abundant in the meadow-steppe areas: Oedipodacaerulescens, Chorthippusbiguttulus and locust larvae. Gryllulusdesertus, Calliptamusitalicus and Chorthippusmacrocerus were not found at all in the experimental areas.

In June-July, 14 insects/100m2 of Hemiptera were found in the area near the pond and two experimental plots in forest, in August-September their number was 61 insects/100m2. In the meadow- steppe area (three research areas) 8 insects/100m2 were found in June-July, and in August-September no bugs were found at all. This situation with the number of Hemiptera can be explained by the lack of fodder for young and adults in the meadow-steppe research areas.

The following species of Hemiptera were most abundant in the area near the pond and in two forest areas: Emblethisverbasci, Emblethisgriseus and Megalonotuschiragra. Dicranomerusagilis, Myodochidae were not found at all in the experimental areas.

Emblethisverbasci was the most widespread in the meadow-steppe areas. The following species of Hemiptera: Emblethisgriseus, Emblethisdenticollis and Megalonotuschiragra were not found at all in these research areas.

The basis of the fauna of the botanical garden is widespread species (cosmopolitan, trans- and western Palearctic, trans- and western Eurasian, Scythian) - 88%.

In most cases, these are evrybiont species that are well adapted to life in agrocenoses and in urbanized areas; thus, the terrestrial insect fauna of the botanical garden has an appearance characteristic of human-disturbed areas. It has practically no species characteristic of virgin steppes.

The terrestrial insect fauna of the botanical garden is dominated by steppe and polyzonal species (57%), as well as a large share of field, steppe-field and meadow-field species (29%). The analysis of the abundance of field (evrybiont) and virgin species showed that quantitatively the basis of the fauna is field species.

The analysis of the trophic specialization of the insect fauna of the botanical garden showed that it contains representatives of 7 trophic groups:

1 - Phytosaprophages: Blapshalophila; Opatrumsabulosum;

2 - Phytophages: Otiorhynchusligustici; Eusomusovulum ;

3 - Phytophages: Onthophagussemicornis;

4 - Zoophages: Cymindusangularis; Taphoxenusgigas;

5 - Necrosaprophages: Silphaobscura;

6 - Zoosaprophages: Taphoxenusgigas;

7 - Zoophytophages: Harpaluszabroides; Ophonusrufipes.

56% of species are species with one or another degree of phytophagy, zoophagy is characteristic of 40% of species; pure phytophages make up 32% of species, pure zoophages 24%.

Predominance of phytophages is characteristic of agrocenoses and disturbed ecosystems.

We used four indexes for the assessment of the biodiversity of the insect fauna of the botanical garden: Shannon, Simpson, Menhinick and Berger-Parker. The following values were obtained, which are presented in

Table 2.

One trend can be clearly observed when analyzing the data - a decrease in the biodiversity of entomofauna in August; this is explained by the drying of biotopes at the end of summer, especially in 2018. If we compare the indices by biotopes, then in June biodiversity is much higher in the meadow areas of the botanical garden, and in August these indicators are slightly higher in the areas near the lake and in the forest part of the botanical garden, which can also be explained by environmental factors and their influence on terrestrial insect organisms.

Conclusions

References

fauna terrestrial insect carpathian botanical garden