The status of glaciers is alarming globally with still unknown effects on freshwater ecosystems. Thegeneral aim of this study was to investigate the structural and functional changes in the macroinvertebrate communityin stream networks fed by shrinking glaciers in relation to environmental variables. Feeding glaciers haddifferent surface areas and retreating rates. We selected 10 study sites in the Italian Alps, spanning five kryal, twoglacio-rhithral, two krenal and one proglacial pond, sampled twice in summer 2018. Eight of these sites weresampled previously between 1996 and 2014. In all, in 2018, > 15,000 individuals (73 taxa) were collected, of which82 % were chironomids (Diptera Chironomidae) (33 taxa). Diamesa zernyi gr. (Chironomidae Diamesinae) wasthe most frequent and abundant taxon, followed by Oligochaeta and Chironomidae Orthocladiinae. Taxonomical(Shannon index) and functional (based on functional feeding groups) diversity both increased with decreasingglacial influence (estimated as glacial index, GI, based on distance from the glacier snout of each site and glacierarea), from kryal to glacio-rhithral and krenal habitats. Taxa distribution was explained mainly by GI, maximumwater temperature, substrate stability, silica, epilithic chlorophyll-a, and benthic particulate organic matter. Thesame variables explained temporal differences in the community structure for the eight sites re-sampled in the lasttwo decades. Among the taxa best associated with high GI was the chironomid Diamesa steinboecki, that in 2018was exclusive of the kryal sites with GCC (% glacier cover in the catchment, expressed in a range from 0 %–100 %)> 50 % and maximum temperature < 5 °C. This species was absent only in the kryal site C0 (GCC = 33 %), whereit was dominant in 1996 –1997. This site was still fed by ice melt in 2018, but resembled a glacio-rhithral site inhabitat features (e.g. maximum temperature > 6 °C) and biota (e.g. % Diamesa spp. < 30 %). In C0, it was evidentthat in the last 22 years, the macroinvertebrate community changed remarkably. This change was due to upstreammigration of generalist insect species to sites once exclusive for kryal species with consequent changes in food webstructure and loss of strictly kryal species, first D. steinboecki that we propose as the “flagship” species of the kryalin the Alps. The site C0 represents a “tipping point”, showing us the effects of climate change on alpine biodiversityin a relatively short period; unfortunately, there are many such sites in the Italian Alps.

Polymerase chain reaction (PCR)-based genotyping of mutations in the voltage-sensitive sodium channel (vssc) associated with resistance to pyrethroid insecticides is widely used and represents a potential early warning and monitoring system for insecticide resistance arising in mosquito populations, which are vectors of different human pathogens. In the secondary vector Aedes albopictus—an Asian species that has invaded and colonized the whole world, including temperate regions—sequencing of domain II of the vssc gene is still needed to detect the V1016G mutation associated with pyrethroid resistance. In this study we developed and tested a novel allele-specific PCR (AS-PCR) assay to genotype the V1016G mutation in this species and applied it to the analysis of wild populations from Italy. The results confirm the high accuracy of the novel AS-PCR and highlight frequencies of the V1016G allele as >5% in most sampling sites, with peaks of 20–45% in coastal touristic sites where pyrethroid treatments are extensively implemented, mostly for mosquito nuisance reduction. The high frequency of this mutation observed in Italian Ae. albopictus populations should serve as a warning bell, advocating for increased monitoring and management of a phenomenon which risks neutralizing the only weapon today available to counteract (risks of) arbovirus outbreaks.

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Glaciers are shrinking due to global warming, resulting in a diminishing contribution of ice and snowmelt to headwaters and subsequent consequences to freshwater ecosystems. Within this context, we tested whether water-stable isotopes are spatio-temporal tracers of (i) water in high altitude periglacial environments, being the isotopic signature of surface water inherited from the snow/icemelt, groundwater, and rainfall; and (ii) regional (year-specific) meteorological conditions, being the isotopic signature of precipitations affected by air temperature, humidity and aqueous vapour origin, ascribing stable isotopes to the list of "essential climate variables" (ECVs). To this end, we investigated the ionic and isotopic composition (δ 18 O and δ 2 H) of six high-altitude streams and one pond in the Italian Alps (Noce and Sarca basins) during the ablation season in 2018. Differences between habitat types (pond, kryal, rhithral, krenal) were detected. More negative values of δ 18 O and δ 2 H were recorded in the kryal and glacio-rhithral sites, dominated by ice and snowmelt, in early summer. Less negative values were recorded in these sites in late summer, as well as in the krenal sites, which were dominated by groundwater and rainfall inputs. The isotopic results also show that the complex alpine orography influences air masses and moisture, ultimately resulting in isotopic differences in the precipitations of neighboring but distinct catchments (Sarca and Noce basins). On average, less negative values were recorded in the Sarca basin, characterized by a higher contribution of precipitation of Mediterranean origin. In general, isotopic results of the entire water population appeared to be strongly influenced by the regional climatic anomaly of 2018, which was anomalously warm. Therefore, the study will provide additional information for the climate change debate, proposing water isotopes as ECVs for assessing change in a warmer future.Water 2020, 12, 390 2 of 18 future, mean annual runoff is expected to progressively decrease in glacier-fed streams, and overall changes in the hydrological behavior of small-and large-scale catchments are expected [9,10].Glacier shrinking and its consequences on glacier-fed streams induce variation in the physical, chemical and biological features of freshwater ecosystems [11,12]. This profoundly affects the ecosystem services that glacier-fed rivers provide to humans, particularly the provision of water for agriculture, hydropower, and consumption [11,13,14]. This is crucial for mountain settlements in glacialized regions, where the snow and ice melt contribution, especially in spring and summer, is the most relevant water source for several uses [13][14][15]. In particular, streams draining in Alpine areas are generally identified as some of the environments most sensitive to climate change [16,17]. This is particularly true for glacier-fed streams and rivers [18]. Within this scenario, runoff changes also impact on the biological community structure [13,19]. In fact, alpine stream...