https://www.selleckchem.com/ Overall, our results indicated that damming induced changes in physiochemical variables (e.g., temperature, conductivity, and nutrients), accompanied by alterations in flow regime and longitudinal connectivity, increased replacement and loss of taxa or traits. These changes have consequently led to alteration of macroinvertebrate taxonomic and functional community dissimilarity and affected the relative effects of environmental and spatial factors on beta diversity and its components. Our study helps understand the ecological processes associated with dam impacts on macroinvertebrate biodiversity and the conservation potential of undammed rivers. In addition, our results showed that taxonomic and functional beta diversities can provide complementary information about dam impacts on riverine biodiversity.In the nocturnal boundary layer, nitrate radical (NO3) has an important contribution to atmospheric chemistry through oxidation of nitrogen oxides and hydrocarbons. Vertical distributions of NO2, O3 and NO3 were measured by four differential optical absorption spectroscopy instruments at meteorological tower in Beijing from June 1 to July 22, 2019. The results show the mean diurnal variations of NO2, O3, and NO3 display a single peak (up to 65.0 ppbv, 196.8 ppbv and 317.5 pptv, respectively) in time. O3 and NO3 mixing ratios generally increased against heights, which is opposite to NO2, suggesting the contribution of O3 to NO3 production at higher altitude. According to the correlation coefficients between NO3 production rates (PNO3) and NO2 or O3 levels, PNO3 was sensitive to NO2 mixing ratio at higher altitude but to O3 near the ground. Averaged NO3 lifetimes (τNO3) of lowest, middle, upper and highest layer intervals were 104, 118, 164 and 213 s, respectively, which indicates τNO3 increase against height and explains why NO3 mixing ratios are larger at higher altitude to some extent. Main control factors of NO3 removal changed from gas