Search results for "taxonomic"
showing 8 items of 148 documents
Phylogenetic diversity and affiliation of tropical African ectomycorrhizal fungi
2022
Ectomycorrhizal fungi form a mutualistic symbiosis with plant roots, and are key for nutrient cycling in many ecosystems. Here we study the ectomycorrhizal fungal communities in the Oueme Superieur reserve forest in Benin (West Africa). We use phylogenetic methods to test if the species from the study site are closer to other tropical African species than to species from other regions. The Oueme Superieur community was represented by nine Operational Taxonomic Units in Amanitaceae, one in Boletaceae, one in Cantharellaceae, one in Cortinariaceae, two in Inocybaceae, fourteen in Russulaceae and three in Sclerodermataceae. Of these thirty-one Operational Taxonomic Units, twenty had no record …
Notes on Shore Flies (Diptera: Ephydridae) from Finland and north-western Russia
2015
The recent checklist of the Ephydridae of Finland by Zatwarnicki and Kahanpää (2014) mentioned 13 ephydrid species as new for Finland without further details. This paper presents detailed records for those species and a few other species of interest. Four species are recorded for the first time from Russia. Trimerina indistincta Krivosheina, 2004 is herein considered as a new junior synonym of Trimerina microchaeta Hendel, 1932, syn. nov.
Study of the impact of viticultural practices on arbuscular mycorrhizal fungi associated with vines
2021
Arbuscular mycorrhiza, a mutualistic symbiosis established between plants andarbuscular mycorrhizal fungi (AMF), providesmany ecosystem services such as improved soilstructure, increased plant growth and nutrition,and improved tolerance to biotic and abioticstresses. However, intensive agricultural practicesand the use of phytosanitary products as forexample herbicide and fungicides, have a strongimpact on communities of soil microorganisms,including arbuscular mycorrhizal fungi, as well ason biological mechanisms within the ecosystem.This thesis wotk is part of the European Biovineproject supported by the European Commissionthrough the CORE Organic Cofund.The aim of this research work was …
Niche position drives interspecific variation in occupancy and abundance in a highly-connected lake system
2019
Highlights • We studied interspecific variation in occupancy and abundance of freshwater species. • Occupancy and abundance correlated positively for both diatoms and macroinvertebrates. • Niche position had clearest effects on variation in occupancy and abundance. • The more marginal the niche position, the rarer a species is. We examined how niche position, niche breadth, biological traits and taxonomic relatedness affect interspecific variation in occupancy and abundance of two commonly-used biological indicator groups, i.e. diatoms and macroinvertebrates. We studied 291 diatom and 103 macroinvertebrate species that occupied the littoral zones of a large (305 km2) highly-connected freshw…
Predictive models in assessment of macroinvertebrates in boreal rivers
2009
Jukka Aroviita tutki väitöskirjassaan jokien ja purojen biologisen tilan mittaamismenetelmiä. Aroviita osoitti, että ihmistoiminnan aiheuttamat biologiset muutokset voivat jäädä havaitsematta, jos eliöyhteisöjen luonnollista taustavaihtelua ei oteta kunnolla huomioon.- Tällöin vesistöjen saatetaan arvioida olevan paremmassa kunnossa kuin ne todellisuudessa ovatkaan. Muutosten tunnistamistarkkuuden tulisi olla mahdollisimman hyvä, sillä tila-arvioilla on myös juridisesti määräytyviä yhteiskunnallisia ja taloudellisia seuraamuksia, Aroviita toteaa. Vielä 1990-luvulla järvien ja jokien tilaa arvioitiin suurelta osin ihmisen näkökulmasta ja veden kemian perusteella. Nykylainsäädäntö edellyttää …
Typologia województw pod względem ekonomicznego zrównoważenia rolnictwa
2016
Celem pracy jest próba oceny poziomu ekonomicznego zrównoważenia rolnictwa w Polsce na podstawie wybranych wskaźników. Ideą rolnictwa zrównoważonego jest zracjonalizowanie intensywności produkcji, co wpływa na jakość środowiska naturalnego. Zasady zrównoważonego rozwoju zrodziły się z potrzeby uwzględnienia w7 procesach gospodarowania interesów obecnych i przyszłych pokoleń, zwłaszcza pod kątem zachowania walorów środowiska. Pojęcie zrównoważonego rozwoju rolnictwa ma charakter wielopłaszczyznowy i wieloaspektowy. Początki postrzegania rozwoju rolnictwa poprzez pryzmat ekonomicznych korzyści oraz uwzględnianie ekologii w produkcji, w krajach Unii Europejskiej, sięgają lat 70. minionego wiek…
Sensitivity of bipartite network analyses to incomplete sampling and taxonomic uncertainty
2023
Bipartite network analysis is a powerful tool to study the processes structuring interactions in ecological communities. In applying the method, it is assumed that the sampled interactions provide an accurate representation of the actual community. However, acquiring a representative sample may be difficult as not all species are equally abundant or easily identifiable. Two potential sampling issues can compromise the conclusions of bipartite network analyses: failure to capture the full range of interactions (sampling completeness) and use of a taxonomic level higher than species to evaluate the network (taxonomic resolution). We asked how commonly used descriptors of bipartite antagonisti…
Inferring phytoplankton community composition with a fatty acid mixing model
2015
Abstract. The taxon specificity of fatty acid composition in algal classes suggests that fatty acids could be used as chemotaxonomic markers for phytoplankton composition. The applicability of phospholipid-derived fatty acids as chemotaxonomic markers for phytoplankton composition was evaluated by using a Bayesian fatty acid-based mixing model. Fatty acid profiles from monocultures of chlorophytes, cyanobacteria, diatoms, euglenoids, dinoflagellates, raphidophyte, cryptophytes and chrysophytes were used as a reference library to infer phytoplankton community composition in five moderately humic, large boreal lakes in three different seasons (spring, summer and fall). The phytoplankton commu…