Search results for "Aquatic insect"
showing 8 items of 8 documents
Beta diversity of stream insects differs between boreal and subtropical regions, but land use does not generally cause biotic homogenization
2021
Made available in DSpace on 2021-06-25T10:17:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Previous studies have found mixed results regarding the relationship between beta diversity and latitude. In addition, by influencing local environmental heterogeneity, land use maymodify spatial taxonomic and functional variability among communities causing biotic differentiation or homogenization. We tested 1) whether taxonomic and functional beta diversities among streams within watersheds differ between subtropical and boreal regions and 2) whether land use is related to taxonomic and functional beta diversities in both regions.Wesampled aquatic insects in 100 subtropical (Brazil…
Community size can affect the signals of ecological drift and niche selection on biodiversity
2020
Made available in DSpace on 2020-12-12T01:24:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Academy of Finland Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Ecological drift can override the effects of deterministic niche selection on small populations and drive the assembly of some ecological communities. We tested this hypothesis with a unique data set sampled identically in 200 streams in two regions (tropical Brazil and boreal Finland) that differ in macroinvertebrate community size by fivefold. Null models allowed us t…
Community size affects the signals of ecological drift and niche selection on biodiversity
2019
AbstractEcological drift can override the effects of deterministic niche selection on small populations and drive the assembly of small communities. We tested the hypothesis that smaller local communities are more dissimilar among each other because of ecological drift than larger communities, which are mainly structured by niche selection. We used a unique, comprehensive dataset on insect communities sampled identically in a total of 200 streams in climatically different regions (Brazil and Finland) that differ in community size by fivefold. Null models allowed us to estimate the magnitude to which beta diversity deviates from the expectation under a random assembly process while taking di…
Co-evolution between ectoparasites and their insect hosts: a simulation study of a damselfly-water mite interaction
2001
Summary 1. A simulation model investigating the co-evolution of water mites infesting their aquatic insect hosts during emergence is presented. The model is based on field and experimental studies of the ectoparasitic water mite Arrenurus cuspidator and the damselfly Coenagrion puella. 2. Three scenarios were studied: (1) Only the host was allowed to evolve timing of emergence, while the timing of the parasites' infestation opportunity was held constant. (2) Both host and parasite were allowed to evolve. (3) Only the parasite's timing was allowed to evolve, while the host was constrained completely. 3. In the first two scenarios, parasite abundances decreased in the course of evolution and …
Cryptic biodiversity loss linked to global climate change
2011
Climate impacts on biodiversity are usually assessed at the morphospecies level. An analysis of the distribution and mitochondrial DNA variability of nine montane aquatic insect species in Europe suggests range contractions will be accompanied by severe loss of genetic diversity. These results imply that morphospecies-scale assessments may greatly underestimate potential biodiversity losses from climate change.
Water striders (Heteroptera: Gerromorpha: Gerridae) of Romania with an update on the distribution of Gerris gibbifer and G. maculatus in southeastern…
2018
The Romanian fauna comprises two species of Aquarius Schellenberg, 1800, eight species of Gerris Fabricius, 1794 and one species of Limnoporus Stål, 1868, and we hereby update the distribution and provide insights on the phenology and ecology of all eleven species in this country. We furthermore update the distribution of the two closely related species Gerris gibbifer Schummel, 1832 and G. maculatus Tamanini, 1946 in southeastern Europe. Gerris maculatus is recorded for the first time from Hungary, Montenegro and Slovenia, and the first detailed localities from Romania and Serbia are given. All bibliographic records of G. gibbifer from Romania, Macedonia and Serbia are based on misidentifi…
The Carpathians as a Major Diversity Hotspot in Europe
2011
The Carpathians are one of the major mountain ranges of Europe, but still one of its least studied regions. It is increasingly recognized that they played a major role in the formation and Pleistocene survival of numerous continental, arctic, and arctic–alpine taxa. Many endemic taxa have been described from these mountains. The number of phylogeographic/phylogenetic studies covering at least partially the Carpathians is also increasing. These studies reveal unevenly distributed genetic and taxonomic diversity. In this work, we analyse population genetic structures in the Carpathians revealed by case studies on aquatic insects, comparing them to existing literature data on plants, butterfli…
Hyperspectral Imaging of Macroinvertebrates : a Pilot Study for Detecting Metal Contamination in Aquatic Ecosystems
2018
The applicability of spectral analysis in detection of freshwater metal contamination was assessed by developing and testing a novel hyperspectral imaging (HSI) application for aquatic insect larvae (Trichoptera: Hydropsychidae). Larvae were first exposed to four different cadmium (Cd) concentrations: 0, 1, 10, and 100 μg L−1 for 96 h. Individual larvae were then preserved in ethanol, inspected with microscopy for the number of anomalies in larval gills, and imaged by hyperspectral camera operating with wavebands between 500 and 850 nm. Three additional larvae from each exposure were analyzed for tissue Cd concentration. Although the larval tissue Cd concentrations correlated positively wit…