Effects of Landscape Patterns and Their Changes to Species Richness, Species Composition, and the Conservation Value of Odonates (Insecta).

Aleš Dolný,Filip Harabiš,Stanislav Ožana,Michal Burda

doi:10.3390/insects12060478

Aleš Dolný, Filip Harabiš + Show 2 more

Open Access

https://doi.org/10.3390/insects12060478

Copy DOI

Abstract

Simple SummaryIn this study, we aimed to evaluate the relationship between human transformations of land use/land cover and adult dragonfly diversity. Based on previous studies, we assumed that with increasing rates of environmental degradation and declining levels of naturalness, the representation of species with high conservation value would significantly decrease, which, however, would not affect the regional alpha diversity. Our results have shown that species richness did not correspond to habitat naturalness, but the occurrence of endangered species was significantly positively correlated with increasing naturalness; thus, habitat degradation and/or the level of naturalness significantly affected species composition, while species richness remained unchanged. Based on our analyses, it is evident that most natural areas, and therefore the least affected areas, provide suitable conditions for the largest number of endangered species. This research extends our knowledge about the impact of human activities, especially the conversion and degradation of habitats, on the composition of odonates and freshwater animals at the regional scale.Understanding the impact of the changing proportion of land-use patterns on species diversity is a critical issue in conservation biology, and odonates are good bioindicators of these environmental changes. Some freshwater ecosystems that have been modified due to human activities can serve as important secondary habitats for odonate assemblages; however, the majority of studies addressing the value of secondary habitats in industrial and urban areas for adult dragonfly diversity have been limited to the local scale, and the value of such habitats for gamma diversity is still unclear. The aim of this study was to determine the relationship between human transformations of land use/land cover and dragonfly diversity. We interpolated the information based on dragonfly occurrence per grid cell and land cover data, indicating naturalness and degradation in 677 grid cells in the Czech Republic. Species richness did not correspond to habitat naturalness, but the occurrence of endangered species was significantly positively correlated with increasing naturalness; thus, habitat degradation and/or the level of naturalness significantly affected species composition, while species richness remained unchanged. Threatened species that occur predominantly in natural areas and threatened species with a dominant occurrence in degraded squares were also separated, which indicated that the conservation of the latter should be prioritised.

Highlights

Biodiversity faces growing pressures from urbanisation and other human activities that eliminate large portions of the habitat from the landscape
This study aims to clarify the relationship between human transformations of land use/land cover and dragonfly diversity
The first dataset contained data about the spatial distribution of areas with different coincidences of natural biotopes from Boucníková & Kučera [30]. We used their information based on the CORINE land cover data from 1990 and 2000 for naturalness, which is the proportion of natural biotopes in landscape types, and degradation, expressed as a proportion of the area covered by biotopes with low representativity and conservation status, in a grid cell of all 677 cells in the Czech Republic (Figure 1)

Summary

Introduction

Biodiversity faces growing pressures from urbanisation and other human activities that eliminate large portions of the habitat from the landscape. Fragmentation, conversion, and degradation of habitats are considered as causes of global biodiversity decline [1,2,3], and recent evidence suggests that human-dominated areas lose significantly more biodiversity than regions where more natural habitats remain, including aquatic and terrestrial environments [3,4]. Dudgeon et al [8] identified five major threat categories to global freshwater biodiversity: overexploitation, water pollution, flow modification, and destruction or degradation of habitats, which applies to protected areas [9]. Other important habitat changes in freshwater ecosystems include the loss of wetlands owing to drainage and other conversions from natural habitat to agriculture or urbanization [10]. Domestic and urban pollution, agriculture (and its pollution), urbanisation, and recreational development are among the biggest threats to the biodiversity of odonates [11]

Objectives

Methods

Results

Discussion

Conclusion