Land-use practices in Mongolia can lead to environmental degradation and consequently affect the structure and function of biological communities. The main aim of this study was to determine land-use effects on freshwater macroinvertebrate communities based on their response to grazing and mining, using a trait-based approach (TBA). The functional structure of macroinvertebrate communities was examined using 86 categories of 16 traits. A total of 13 physical and chemical variables were significantly different among the levels of land-use intensity. Significant declines in functional diversity were observed with increased land-use intensity. The community weighted mean of 19 trait categories for 11 traits varied significantly among different levels of land-use intensity. Traits were significantly explained by environmental variables across a land-use intensity gradient. Water temperature, gravel, nitrate, silt, and cobble were the main predictor variables and explained 28% of the total variance of the trait variation. The functional structure of the macroinvertebrate community was strongly related to environmental conditions. The TBA is an important method in assessing disturbance responses in freshwater communities of steppe and taiga regions, such as in Mongolia and other countries in Central Asia and will be useful in finding best management practices for conserving aquatic ecosystems.

Overgrazing is one of the major land-use impacts in Mongolia leading to habitat degradation and subsequent impairment of biological diversity. This study examined macroinvertebrate diversity among sites with different grazing intensities in Hövsgöl, Mongolia, to test whether the taxonomic and functional structure of the macroinvertebrate community differs among streams with different grazing intensity. The 14551 total identified specimens comprised 78 genera in 27 macroinvertebrate families from the six streams. Exponential Shannon index and weighted functional diversity were significantly higher in low grazing sites than in moderate and high grazing sites, however there was no significant difference between moderate to high grazing intensity. Macroinvertebrate community composition was not significantly different between low and moderate or low and high grazing intensity sites. SIMPER analysis revealed the taxon with the highest contribution to dissimilarity among the levels of grazing. Thirteen trait categories from eight traits differed significantly between sites with varying grazing pressure. The community weighted means for four of these traits were filtered by high grazing intensity: dissemination, resistant form, current velocity, and saprobity. Although the other four traits differed significantly, they did not respond directly to grazing intensity. Further knowledge of traits, especially regarding physiological capabilities, is needed to better understand macroinvertebrate/environment relationships, but overall, these findings suggest that macroinvertebrate diversity components were affected by grazing.

Current understanding of how streamflow in terminal basins is driven by climatic and hydrogeomorphic characteristics is limited, despite the fact that these closed systems show an increased sensitivity to climate change in terms of streamflow and an increase in demand for water resources. We examined streamflow patterns in 2 major terminal basins, the Great Basin in the United States (US-TB) and the Central Asian Internal Drainage in Mongolia (MN-TB). We obtained daily flow data spanning 1990 to 2014 for both basins, established hydrological indices (HIs), and selected a subset of HIs that best described streamflow patterns. A between-class analysis was used to detect differences in streamflow patterns between these basins. We employed the RESonate tool to delineate hydrogeomorphic patches (HPs), evaluated streamflow variation across distinct HPs, and examined ranges of streamflow variation and hydrogeomorphic variation expressed in each of the terminal basins. Of a subset of 45 HIs, seasonal high flow, flooding frequency, and baseflow best characterized streamflow in HPs. Streamflow in MN-TB was driven by high flow duration, whereas in US-TB streamflow was characterized by significantly larger low-flow conditions. The MN-TB exhibited a greater range of streamflow variation between HPs but showed a lesser range of variation in hydrogeomorphology. Our study is the first to establish HIs and describe streamflow patterns in terminal basins on a large scale. Our study also contributes needed perspectives on streamflow patterns in 2 different terminal basins with complex topographies, thereby providing valuable information for stream ecologists and water resource managers.

Phytotelmata are temporary pools of rainwater impounded on plants. These pools provide aquatic habitats in which immature stages of insects live. Zingiberales plants can have two types of phytotelmata, the bract pool on the inflorescence and the tubes formed as young leaves unroll. The Diptera fauna of these habitats are poorly known. This study reports on a systematic inventory of invertebrate communities from Zingiberales in Costa Rica and Peru. Collections of invertebrates were extracted from 251 phytotelmata representing six species of Zingiberales – Heliconiaceae: Heliconia robusta Pax, Heliconia stricta Huber, and Heliconia tortuosa Griggs; Marantaceae: Calathea lutea Schult; and Zingiberaceae: Alpinia purpurata (Vieillard) K. Schumann and Renealmia spp. Aquatic Diptera (620 larvae and pupae) were found in 34 samples (32 bract pools and 2 leaf rolls). These Diptera were extracted, sorted and identified to 22 morpho species in 5 families of aquatic ‘Nematocera’, two families of aquatic Brachycera, and one group of undetermined aquatic Brachycera families. Chironomidae (159 individuals, 3 species) were the numerically dominant family, then Syrphidae (141 individuals, 3 species), and Psychodidae (81 individuals, 2 species). The Peru phytotelmata contained more species of Diptera than the Costa Rica phytotelmata. Altogether, four new host associations are documented between aquatic Diptera and Zingiberales phytotelmata habitats in Costa Rica and 14 such records in Peru. Results of a cluster analysis indicate that communities of aquatic Diptera varied between sampling sites and within and between plants. Phytotelmata add to habitat heterogeneity and are likely to increase diversity of aquatic Diptera and other taxa; therefore, phytotelmata should be included in assessments of aquatic Diptera.

Parakiefferiella ferringtoni sp. n., previously recorded as the provisional taxon Orthocladiinae Genus 5 sensu Coffman and Ferrington (2008), is described based on larval, pupal, pharate male and female material. This species resides in the Pacific Northwest region of the Nearctic. The morphology of P. ferringtoni sp. n. blurs the lines between genera of the Parakiefferiella group. We review the state of generic taxonomy of the Parakiefferiella group, with an emphasis on providing explicit morphological synapomorphies to delineate each genus, although Parakiefferiella Thienemann and Lappokiefferiella Tuiskunen have no unambiguous synapomorphies.