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Thesis (Masters by research(Public Health))--University of South Australia, 2022. Includes bibliographical references (pages 152-170) Land-clearing in urban areas is resulting in loss of biodiversity. Native revegetation is being used to restore degraded urban landscapes but its influence on invertebrate diversity is poorly understood. This project investigated four native vegetation characteristics and invertebrate diversity by sampling invertebrates at eleven urban plots. Invertebrates were identified to morphospecies with ants being a focus. Statistical analysis showed variable results. Remnant plots had the highest diversity of invertebrates yet some open unrevegetated plots had similarly high diversity than proximal revegetated plots. Specific invertebrate taxa responded to some of the habitat characteristics at some vegetation types. This study highlights the complex relationships between native revegetation and invertebrate diversity in urban areas and might be useful for urban green space planning.

Mangroves in the Arabian Gulf are under pressure from land use change, leading to compensatory planting at sites without natural mangroves. In this study, we examine the potential long-term success of this form of afforestation of mangroves as a conservation measure supporting biodiversity. We compared the community of benthic macrofauna (in total 13,522 individuals from 75 species) and physical parameters at 15 sampling points in five afforested mangrove communities and 19 stations in four natural mangrove communities in Qatar. Three decades after afforestation, there were no significant differences between the benthic macrofauna in natural and afforested mangroves as regards total abundance, species richness, Shannon’s diversity, effective number of species, or evenness. Only species richness of Crustacea was significantly higher in natural mangroves. Total organic carbon (TOC), sand, and clay content did not differ. This contradicts findings at the same locations 10 years after afforestation, when benthic macrofauna diversity, TOC, and clay content were lower at afforested sites than at natural mangrove sites. Our results suggest that compensatory planting of mangroves in areas without previous natural occurrence can potentially compensate for loss of biodiversity due to coastal development and that physical parameters may become more similar in afforested mangroves and natural mangroves over time. Furthermore, the increase in TOC in sediments in afforested mangroves over time can help mitigation of climate change. Importantly, the results highlight the need for long-term studies and perspectives when evaluating conservation practices.

Publisher's version (útgefin grein), In 1937, S.L. Tuxen studied the animal community of hot springs in Iceland, and classified springs according to their relative temperature into cold, tepid, and hot. Eighty years after Tuxen’s study, we revisited some of the hot springs in Skagafjörður, Northern Iceland. Our aim was to compare the invertebrate community of 1937 and today, and to assess the stability of hot spring habitats over the years. To test Tuxen’s spring classification on an ecological basis, we furthermore collected chironomid larvae from 24 springs of a broad range of temperature, with samples taken both at the surface area of the spring and at the groundwater level. The chironomid species composition of hot springs differed from that of cold and tepid springs. Whereas Cricotopus sylvestris, Arctopelopia sp., and Procladius sp. characterised the chironomid community in Icelandic hot springs, cold and tepid springs were dominated by Eukiefferiella minor, Orthocladius frigidus and Diamesa spp. Community composition analyses and the exclusive occurrence of taxa in one of the temperature classes validated the ecological relevance of Tuxen’s spring classification for the chironomid species community. Both environmental parameters and invertebrate community of Icelandic hot springs seem to be the same as 80 years ago. Although springs have the potential to provide stable habitats, they are currently under high anthropogenic pressure, and should be increasingly considered in nature conservation., Icelandic Research Fund (RANNÍS), grant nr. 141863-051

International audience; In Neotropical rainforest canopies, phytotelmata ("plant-held waters'') shelter diverse aquatic macroinvertebrate communities, including vectors of animal diseases. Studying these communities is difficult because phytotelmata are widely dispersed, hard to find from the ground and often inaccessible. We propose here a method for placing in tree crowns "artificial phytotelmata'' whose size and shape can be tailored to different research targets. The efficacy of this method was shown while comparing the patterns of community diversity of three forest formations. We noted a difference between a riparian forest and a rainforest, whereas trees alongside a dirt road cutting through that rainforest corresponded to a subset of the latter. Because rarefied species richness was significantly lower when the phytotelmata were left for three weeks rather than for six or nine weeks, we recommend leaving the phytotelmata for twelve weeks to permit predators and phoretic species to fully establish themselves. (C) 2017 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

International audience; Alluvial wetlands provide an important regulating service, the water purification, through the removal of excess nutrients. In those habitats, nitrogen removal by the denitrifying bacterial community is hypothesized to interact with the co-existing invertebrate communities. Yet, few studies reported the infield relationship between invertebrate and microbial communities, where biotic and abiotic interactions are complex. We aimed at exploring the relationship between the invertebrate diversity and microbial denitrification process involved in the water purification service in an alluvial wetland. Subterranean water samplings were seasonally collected from April 2013 to March 2014. Eleven hyporheic habitats were accessed through piezometers dispersed over a meander located in the alluvial plain of the Garonne River (Southwest of France). Physicochemical, hydraulic characteristics, bacterial and invertebrate communities were simultaneously investigated as related factors for potential denitrification rates. Significant spatial gradients of invertebrate diversity, potential denitrification rates, the concentrations of dissolved oxygen, dissolved organic carbon, ammonium and nitrate ions and conductivity were observed in the groundwater of the Monbequi meander. The autumn campaign (9th October), which was performed after a long period of hydrological stability and low discharge, showed a significantly positive linear relationship between invertebrate diversity and potential denitrification rates. An overall significant and positive correlation between invertebrate and bacterial communities’ compositions was found over the four seasons. When each season was considered independently, this relationship was only significant during the autumn campaign. Such observations indicated the positive cross-communities’ interactions that existed between the invertebrate diversity—bacterial communities’ composition and their activity of denitrification. The autumn campaign was suggested to be regarded as a “hot moment” to observe this biodiversity/function relationship, when biological influences on water purification processes were probably not concealed by stronger influences of physical factors. Furthermore, this study showed that optimal potential nitrate removal was supported by a combination of biotic and abiotic conditions: relatively low temperature, oxygen and nitrate concentrations, diverse invertebrate fauna, relatively high dissolved organic carbon and ammonium concentrations.

Birds are an important part of the agricultural landscape, as having nature value, but also as pest control agents and bio-indicators for the health of the environment. Here we look at linear non-crop elements in agricultural areas as a potential source of food for nestlings of avian species. We measured invertebrate availability as it relates to structural complexity at the local and landscape levels in three counties in central Illinois. Invertebrates were measured with taxonomic diversity, abundance, and estimated biomass during spring of 2012 and 2013. Our study shows that easily modifiable field edge characteristics have the greatest impact on invertebrate diversity and abundance, as compared to field and landscape features. This finding shows that a potential invertebrate food source as measured by both diversity and biomass, may be easily enhanced without changes to agricultural practices.

We compiled 46 broadscale data sets of species richness for a wide range of terrestrial plant, invertebrate, and ectothermic vertebrate groups in all parts of the world to test the ability of metabolic theory to account for observed diversity gradients. The theory makes two related predictions: (1) In-transformed richness is linearly associated with a linear, inverse transformation of annual temperature, and (2) the slope of the relationship is near -0.65. Of the 46 data sets, 14 had no significant relationship; of the remaining 32, nine were linear, meeting prediction 1. Model I (ordinary least squares, OLS) and model II (reduced major axis, RMA) regressions then tested the linear slopes against prediction 2. In the 23 data sets having nonlinear relationships between richness and temperature, split-line regression divided the data into linear components, and regressions were done on each component to test prediction 2 for subsets of the data. Of the 46 data sets analyzed in their entirety using OLS regression, one was consistent with metabolic theory (meeting both predictions), and one was possibly consistent. Using RMA regression, no data sets were consistent. Of 67 analyses of prediction 2 using OLS regression on all linear data sets and subsets, two were consistent with the prediction, and four were possibly consistent. Using RMA regression, one was consistent (albeit weakly), and four were possibly consistent. We also found that the relationship between richness and temperature is both taxonomically and geographically conditional, and there is no evidence for a universal response of diversity to temperature. Meta-analyses confirmed significant heterogeneity in slopes among data sets, and the combined slopes across studies were significantly lower than the range of slopes predicted by metabolic theory based on both OLS and RMA regressions. We conclude that metabolic theory, as currently formulated, is a poor predictor of observed diversity gradients in most terrestrial systems.

To verify whether the variability in benthic invertebrate communities along the mountainous Czarny Dunajec River is mainly driven by the variation in hydromorphological or water quality, diversity of the communities was determined for 18 cross-sections with 1–5 low-flow channels and compared with the complexity of physical habitat conditions and with physico-chemical water quality. An increase in the complexity of flow pattern in the river was associated with increasing cross-sectional variability in physical habitat parameters. Distinct hydromorphological characteristics of the cross-sections with a given number of low-flow channels were especially pronounced if the analysis was limited to the parameters measured directly, whereas calculated complex hydraulic and sedimentary variables represented information overload. Taxonomic richness of the invertebrate communities was unrelated to physico-chemical water parameters, which consistently pointed to the high water quality. Instead, the richness positively correlated with a degree of variation in physical habitat parameters and was best predicted by the number of low-flow channels in a river cross-section. This study indicates that physical habitat complexity in a mountain river can be considered a proxy to the diversity of its invertebrate communities and that restoration of such complexity will be necessary for future recovery of invertebrate communities in impacted river sections.

1. As measuring biodiversity in its entirety is impractical, there is a need for bioindicators. This study tested the hypothesis that parasitoid Hymenoptera are potential bioindicators that provide a useful means to assess the wider biodiversity of arthropod populations in agro-ecosystems. There are a range of theoretical arguments to support such a claim, including the high trophic position of these taxa within the arthropod communities in which they occur, and the unique nature of their biological relationships with the majority of terrestrial arthropod groups.\ud \ud \ud 2. A survey of 48 commercial farms was conducted and Generalized Linear Models used to investigate relationships between six taxa—parasitoid Hymenoptera, Coleoptera, Hemiptera, Diptera, Araneae and plants (species richness and sward height)—in agricultural grasslands. As well as relationships between these groups, the relationship of each individual group to the overall biodiversity of all other arthropod groups was explored.\ud \ud \ud 3. Both abundance (r2 = 0·58) and taxon richness (r2 = 0·54) of parasitoid Hymenoptera had stronger relationships with overall arthropod taxon richness than any other arthropod group investigated. Parasitoid abundance also had a positive relationship with species richness of Coleoptera (r2 = 0·23) and Hemiptera (r2 = 0·47).\ud \ud \ud 4. An historical data set demonstrated how the relationship between parasitoid abundance and overall arthropod taxon richness changes over the growing season. July, when the relationship was strongest, is potentially the most useful time to sample.\ud \ud \ud 5. For use in routine monitoring, it is important that an effort be made to understand the seasonal influence on the relationship in the context being studied. Equal sampling effort must be made for all sites being compared and sites should be sampled as close together in the season as is possible.\ud \ud \ud 6. Synthesis and applications. We show that, within agricultural grasslands, both the abundance and taxon richness of parasitoid Hymenoptera are more closely related with overall arthropod diversity than any other arthropod group investigated. The use of parasitoid abundance provides a simple and practicable monitoring tool for tracking change in wider arthropod diversity in agro-ecosystems.

Spatial patterns in macroinvertebrate assemblage structure were examined in rivers from 6 main basins in the mountains and the Patagonian plateau, Argentina. Surber samples were taken during the low water period from 36 sites and environmental variables were also assessed. Five site groups were identified using detrended correspondence analysis (DCA), one in the mountains, one in the piedmont, and three on the plateau (north, central and south). DCA axis 1 separated sites along a physical gradient of water velocity and stream order, whereas axis2 separated sites according to geographic location, latitude and substratum size. Piedmont sites had greater species richness than the mountains, north plateau and south plateau sites. Invertebrate density was significantly greater on the north plateau and piedmont than in the mountains and south plateau, whereas diversity (H′) was significantly higher in the mountains and on the piedmont. From a landscape perspective, higher categories in biogeographical classifications (phytogeography, biozones) appear to be most useful for predicting macroinvertebrate assemblages in Patagonian rivers. Amounts of benthic organic matter and the density and biomass of functional feeding groups (FFG) were also examined in a subset of 25 rivers. During base discharge, wood, leaves and total benthic organic matter decreased significantly from the mountains to the plains, but no significant relationship was found between quantity of fine particular organic matter and distance from the source. Shredder biomass decreased significantly from the headwaters downstream, and collector biomass increased. Predator biomass was relatively similar at all sites. A strong association was found between FFGs and their food resources. The EPT index and H′ decreased as desertification status increased suggesting that land degradation influences macroinvertebrate assemblages. Loss of riparian cover as a consequence of overgrazing and other land use practices has negative effects on aquatic environments in Patagonia Fil: Miserendino, Maria Laura. Universidad Nacional de la Patagonia "san Juan Bosco". Facultad de Cs.naturales - Sede Esquel. Laboratorio de Ecología Acuatica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Los hábitats secundarios son importantes en la conservación de la biodiversidad: un estudio práctico sobre los ortópteros en orillas de acequias Se ha demostrado que la biota autóctona puede sobrevivir en hábitats secundarios como cunetas, diques y setos. La finalidad de este estudio es evaluar el valor de las orillas de acequias para la conservación de los ortópteros en un paisaje agrícola en Hungría, a partir del análisis de los datos relativos a la riqueza y la abundancia de especies utilizando modelos mixtos. No encontramos ninguna diferencia en cuanto a la riqueza de especies entre las orillas de acequias aisladas, semiaisladas y en praderas de control. Sin embargo, el grado de aislamiento tuvo un efecto negativo significativo en la abundancia de especies sedentarias. Constatamos que la densidad de vegetación leñosa junto a las orillas de las acequias tenía un efecto negativo en la abundancia total y la abundancia de especies móviles. Se observó la existencia de una relación positiva entre la anchura de las orillas de acequias que estaba cubierta por vegetación y la abundancia de especies del suborden Caelifera y de especies móviles, xerófilas y mesófilas. Nuestros resultados sugieren que la densidad de ortópteros puede ser una medida más sensible de la calidad del hábitat que la riqueza de especies. Concluimos que las orillas de las acequias son un hábitat adecuado para la mayoría de ortópteros, incluidas las especies raras o en peligro de extinción, lo que pone de relieve que debería prestarse más atención a estos y otros hábitats lineales parecidos y que se les debería dar más importancia en la conservación de invertebrados., It has been shown that native biota can survive in secondary habitats such as road verges, dikes and hedges. We aimed to assess the conservation value of ditch banks for orthopterans in an agricultural landscape in Hungary, based on the analyses of species richness and abundance data using mixed–models. We did not find any differences in the species richness between isolated ditch banks, semi–isolated ditch banks and control meadows. The extent of isolation had a significantly negative effect, however, on the abundance of sedentary species. We found that the density of woody vegetation along ditch banks had a negative effect on the total abundance and the abundance of mobile species. Positive relationships were found between the width of ditch bank vegetation and the abundance of Caelifera, mobile, xerophilous and mesophilous species. Our results suggest that the density of orthopterans may be a more sensitive measure for habitat quality than their species richness. We concluded that ditch banks are a suitable habitat for the majority of orthopterans, including rare and endangered species, emphasizing that ditch banks and similar linear habitats should receive more attention and should be given a more prominent role in invertebrate conservation.