# Diversity and Ecology of Thrips (Thysanoptera, Insecta) Assemblages in Słowiński National Park—A Biosphere Reserve on the Baltic Coast (Northern Poland)

## TL;DR

This study explores thrips diversity in Słowiński National Park, revealing how different habitats and environmental factors influence their distribution.

## Contribution

The study identifies 90 thrips species, including a new species, and links their diversity to specific environmental factors in a unique coastal biosphere reserve.

## Key findings

- The Leucobrio-Pinetum forest and Arrhenatheretalia elatioris meadows had the highest thrips species richness.
- Peat bog communities had the lowest thrips diversity.
- Environmental factors like soil moisture, light intensity, and salinity significantly influence thrips assemblage composition.

## Abstract

Słowiński National Park is situated on the Baltic Coast in Poland. It was established in 1967 to protect the most valuable ecosystems, including coastal lakes, marshes, peat bogs, meadows, forests, and, above all, the unique moving dunes of Europe. We aimed to determine the thrips species composition and diversity in the different land ecosystems of the Park. The studies were carried out in 1991 and 1999–2002 across 14 plant communities. We used both quantitative and qualitative methods in our research. A total of 90 thrips species (nearly 40% of the Polish fauna) were recorded, including 71 in quantitative and 74 in qualitative samples. The species-richest habitats were the Leucobrio-Pinetum forest and meadows classified as Arrhenatheretalia elatioris, with 36 and 33 species, respectively. In contrast, the poorest habitats were the peat bog communities Caricetum gracilis and Carici canescentis-Agrostietum caninae with 10 species, and Erico-Sphagnetum medii (17 species). The study also revealed a significant correlation between the thrips assemblage composition and environmental factors, i.e., soil moisture, light intensity, general nutrient availability, and soil salinity.

Słowiński National Park is one of the 23 national parks in Poland and one of the two situated on the Baltic Coast in the country. It was established in 1967 to protect the most valuable ecosystems: coastal lakes, marshes, peat bogs, meadows, forests, and, above all, the dune belt of the Łebska Spit with its unique moving dunes. We aimed to 1. determine the species diversity and structure of thrips assemblages in the most important biotopes of the Park; 2. determine the geographical distribution and food preferences of thrips species; and 3. determine which environmental factors influence the diversity of insect assemblages and which thrips species distinguish these assemblages. The method used in the quantitative research was based on the use of a scoop method; it was supplemented by qualitative research (shaking branches of trees and searching for insects on their host plants). The studies were carried out in 1991 and 1999–2001 in fourteen plant associations. A total of 90 thrips species (nearly 40% of the Polish fauna) were recorded, including 71 in quantitative and 74 in qualitative samples. The study also revealed a significant correlation between the thrips assemblage composition and the following environmental factors: soil moisture, light intensity, general nutrient availability, and soil salinity. In addition, the thrips species with the most significant impact on assemblage composition were identified. The relatively high number of species found, including Taeniothrips zurstrassenii Zawirska, a species new to science, and others rarely recorded in Poland, highlights the value of the SNP habitat diversity in maintaining high Thysanoptera diversity.