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American shad (Alosa sapidissima) are an anadromous fish species native to North America that have an extensive range, but their populations are declining. Acoustic telemetry can play a vital role in better understanding the behavior and survival of this sensitive species, but successfully handling and tagging juvenile American shad can be challenging. We conducted several experiments to determine the best methods for collecting, transporting, holding, and tagging juvenile shad. Minimizing out-of-water handling and the use of a saltwater treatment during collection increased 24 h survival from 78 to 99% after transport. Saltwater was also fundamental in keeping tagged shad alive overnight. Shad as small as 50 mm, were implanted with a dummy acoustic transmitter using a pectoral incision method with no suture. In a 60 d holding evaluation, the tagged fish survived at a rate comparable to their non-tagged counterparts (81.5% for tagged, 70% for untagged). Tagged and untagged shad also had similar survival when exposed to a tank of predators. The results are important for improving conservation efforts for small, sensitive species of fish, like American shad. [ABSTRACT FROM AUTHOR]

This study aims to improve soil vapor extraction (SVE) to address its shortcomings in treating halogenated hydrocarbon-contaminated soil. Indoor simulation experiments based on SVE were conducted to provide technical guidance for the remediation of 1,2-DCA-contaminated soil, with the overall intention of soil repair and ecological restoration. A thermal oxidation SVE (TOSVE) system was designed on the basis of SVE technology for application in the remediation of low-permeability soil contaminated with halogenated hydrocarbons from a chemical plant in Northeast China. Laboratory simulation experiments were conducted based on TOSVE technology to study the removal of target pollutants under different organic contents, moisture and air speeds. For the first time, a new material, scoria, was added to the oxidant at different proportions, and its effect on the exhaust gas treatment efficiency was examined. Thermal extraction improved the extraction efficiency of pollutants from low-permeability soil. Moreover, the adsorption–oxidation effect of 0.1–0.25 mm scoria prepared by 20% Na2S2O8 on 1,2-dichloroethane (1,2-DCA) in tail gas was higher than that of the oxidant without scoria, indicating that scoria is effective in tail gas treatment. [ABSTRACT FROM AUTHOR]

In terms of regional water resources, precipitation is a critical component. The accurate assessment of precipitation is critical for the sensible development and use of regional water resources. The elevation influence on regional infiltration from precipitation at different monitoring locations was evaluated using variations in topography and geomorphology in the Chongli District of Zhangjiakou City, Hebei Province, as a case study area in this study. The findings show that precipitation increases considerably with elevation, with a gradient of 21.3 mm per 100 m. According to this effect, the regional precipitation infiltration was calculated as 6302.20×104 m3, and the comprehensive precipitation infiltration coefficient was 0.056, which demonstrated a substantial impact of the precise elevation effect on the calculation of regional recharge. This finding is helpful for the regional management of water resources. [ABSTRACT FROM AUTHOR]

Acoustic telemetry has been used extensively to study the behavior of aquatic animals. The Juvenile Salmon Acoustic Telemetry System (JSATS) is one such system; it was developed for studying juvenile salmonids but has been used to study numerous species. A recent innovation of the JSATS system is an acoustic transmitter that is small enough to be implanted through injection or small incision that doesn't require sutures. Use of the JSATS system involves deploying cabled acoustic receivers at hydroelectric dams, or other structures, and autonomous acoustic receivers in free-flowing sections of a river. The raw detections from acoustic-tagged fish are processed to remove potential false positives. The clean detections (5,147,996 total) are used to generate detection events and to compute 3-D trajectories (403,900 total), which are used to assign fish to a passage route through a dam. Controlled field testing involving a high-accuracy Global Positioning System receiver is done to validate the submeter accuracy of the trajectories. The JSATS dataset could be reused for expanding the understanding of near-dam fish behavior. Measurement(s) voluntary movement behavior • 3-D trajectory Technology Type(s) acoustic telemetry • Computation Factor Type(s) river • array type Sample Characteristic - Organism Oncorhynchus tshawytscha Sample Characteristic - Environment dam • freshwater biome Sample Characteristic - Location Little Goose Lock and Dam • Snake River • Columbia River • Lower Monumental Lock and Dam • McNary Dam • Bonneville Dam • Ice Harbor Lock and Dam • John Day Dam • Tucannon River Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.14939169 [ABSTRACT FROM AUTHOR]

Nitrogen pollution exceeding the standard because of intensive farming and cropping systems has been a widespread problem in Northeast China. This study investigated the characteristics of functional microorganisms in groundwater in the Bang River farming area. Metagenomic sequencing was used to analyze microbial community structures and Canoco was applied to reveal the response relationship between the microbial community and water environmental factors and to identify changes in the microbial population in response to the addition of electronic donors NH4+-N, NO2−-N, and NO3−-N. The results showed that the dominant microorganisms in groundwater belong to the genera Exiguobacterium, Citrobacter, Acinetobacter, and Pseudomonas, which accounted for more than 40% of the total microbes in the study area. When combined with the results of a water chemical factor test, the dominant bacteria were found to be correlated with Fe2+, Mn2+, NH4+, NO3−, NO2−, HCO3−, DOC, and pH in the water. However, the microbial population changed after the addition of the electron donor, with the genera Pseudomonas, Serratia, Enterobacter, Azomonas, and Ewingella accounting for 97.06% of the total sequences. Indigenous nitrogen-degrading bacteria suitable for low temperature, low oxygen, and oligotrophic groundwater were screened out. The total removal efficiency of NH4+-N, NO2−-N, and NO3−-N in 120 h was 90.83%, 75.04%, and 73.35%, respectively. According to the experimental results, the degradation reaction kinetics followed a pseudo-second-order equation. The results presented herein provide an important scientific basis for the microbial remediation of groundwater contaminated by ammonia. [ABSTRACT FROM AUTHOR]

In order to understand the interaction between surface water and groundwater in Qingshuihe Basin of Chongli Area, the environmental isotopic D, 18O and 222Rn in surface water and groundwater have been analysis, the study results show that: the calculation results based on the D and 18O, the surface water in middle stream of Donggou River has been recharged by groundwater and river water upstream, the percentage of groundwater recharge is 56%; the calculation results based on the 222Rn, the average seepage rate of surface water is 27.8 m3/d/m in the upstream section, and the average recharge rate of groundwater is 17.6 m3/d/m. It is concluded that, the groundwater and surface water interaction is the main characteristics and processes of water cycle in Qingshuihe Basin, and groundwater recharge is the main sources of surface water in draught seasons. [ABSTRACT FROM AUTHOR]