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Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Diannong River, one of the primary freshwater ecosystems in Yinchuan City, is intricately related with the high quality development of the study area. In September 2022, a comprehensive field sampling survey was conducted in the Diannong River basin, encompassing a total of 40 sampling sites. Through the collection of fish specimens and assessment on water environmental factors, an analysis was conducted to assess the structural dynamics and functional diversity of fish community in the Diannong River basin. In addition, the health of aquatic ecosystem in the Diannong River basin was quantitatively assessed by using the Biological Integrity Index methodology. The results indicate that the primary environmental factor affecting the fish community structure in the Diannong River basin is total nitrogen. Significant differences are observed in the species number, community species diversity, and functional diversity of fish between Diannong River, Yuehai, Baohu Lake, and Hequan Lake. The aquatic ecosystem health of Yuehai is superior to that of Diannong River, Baohu Lake, and Hequan Lake. Diannong River and Hequan Lake both exhibit a good level of water quality, while Baohu Lake is at a moderate level. [ABSTRACT FROM AUTHOR]

This study evaluated the aquatic ecosystem health status of the Chengdu Section of Tuojiang River Basin and explored an effective index evaluation method to comprehensive measure ecological health of the river section. We investigated the physical, chemical and biological factors such as hydrology, water quality, habitat, benthic invertebrates and fishes, and conducted a comparative analysis using the WEQIriver comprehensive index method and the RHI comprehensive index method. The WEQIriver comprehensive index method based on water quality, habitat and benthic invertebrates showed that the Chengdu section was in good condition. The results of RHI comprehensive index method based on the natural condition of the riverbank, degree of illegal exploitation and utilization of the riverbank, degree of ecological flow, degree of water pollution, self-purification capacity of the water, fish retention index and public satisfaction showed that the whole basin was in a sub-health state. The results of the two methods showed that the environmental condition of the mainstream and upstream tributaries was better than the downstream tributaries. The environmental conditions of some sites were quite different because they were influenced by the different focuses of the two methods. WEQIriver comprehensive index lays more emphasis on the state of water ecosystems itself, while RHI comprehensive index lays more emphasis on the interference level of human activities to water ecosystems. The better effect is achieved by integrating the two methods in water ecosystem health assessment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The value change and radiation effect of the regional aquatic ecosystem service function were analyzed in order to provide a scientific basis for sustainable development of regional water resources and ecological compensation of a river basin. [Methods] ArcGIS software was used to extract land use data for Luoyang City, Henan Province from 2000 to 2020 in order to obtain the area of water type. The emergy method was used to quantify and analyze the changes of aquatic ecosystem service functions, and the functional radiation was analyzed by the break point model. [Results] From 2000 to 2020 (in five-year time steps), the total emergy values of aquatic ecosystem services at Luoyang City were 8.01×1021 sej， 1.29×1022 sej， 1.27×1022 sej， 1.29×1022 sej， and 1.31×1022 sej, respectively, with a general increasing trend. Among these emergy values, the focus of service composition had shifted from supply function to cultural function. In this system, biodiversity protection, aquatic product production, water resource supply, water resource regulation, and leisure and entertainment functions were dominant. Leisure and entertainment functions have become core functions. In addition, the main transfer areas of the aquatic ecosystem service function in Luoyang City were Songxian County and Luoning County, with total outward transfer values of 3.10×1020 sej and 3.21×1020 sej, respectively. The main transfer areas were Luanchuan County, Yiyang County, Yichuan County, and Ruyang County. [Conclusion] Greater attention will need to be given to ecological protection of water, increasing support and guidance for regional tourism, and reasonably carrying out ecological compensation in areas similar to Luoyang City to promote the coordinated development of the economy, society, and ecology in various regions.

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current situation of single-dose pyraclostrobin products registered on rice, wheat, citrus and potato in China were analyzed, and the exposure concentration in surface water was predicted by using Top-Rice and China-Psem models, as well as their advanced risk to aquatic ecosystem were assessed. The results showed that as of May 2021, there were 25 formualtions of pyraclostrobin registered on four crops in China, which were divided into 5 groups. The proportion of suspension concentrate (SC) was the largest, accounting for 52%, followed by emulsifiable concentrate (EC), accounting for 20%, microcapsule suspension (CS), water dispersible granule (WG) and wettable powders (WP) accounted for 16%, 8% and 4%, respectively. The application range of different formulations of pyraclostrobin and the exposure assessment of different groups on the four crops were investigated, according to the conservative principles of risk assessment. The results showed that the predicted environmental concentration (PEC) of pyraclostrobin on rice ranged from 0.07 to 1.24 μg/L in different scenarios and seasons, the predicted environmental concentration of pyraclostrobin used on wheat ranged from 0.45 × 10−3 to 0.60 μg/L, the predicted environmental concentration of pyraclostrobin used on citrus ranged from 0.03 to 0.76 μg/L, and the predicted environmental concentration of pyraclostrobin used on potato ranged from 0.01 to 0.94 μg/L. Under the current registered application conditions, the risk characterization showed that pyraclostrobin was used on four crops for the recommended method, dosage and number of times, the risk was acceptable. However, in view of its high toxicity to aquatic organisms, the dosage and frequency of application on paddy fields should be cautious, as it poses certain risks to aquatic ecosystems. In the present study, the analysis of its application method mode was conservative, which might be underestimeated the evaluation result in some way. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to evaluate the risk of the use of single-dose imidacloprid products to aquatic ecosystem, based on the conservative principles of risk assessment, different application rates of imidacloprid formulations registered on rice were evaluated and subsequently, the comprehensive risk assessment of these products to aquatic ecosystem was performed using the Top-Rice model and the risk quotient method. These results showed that a total of 375 imidacloprid formulations（single active component） had been registered on rice by June 2020, which could be separated into ten formulation groups. Among these formulations, the wettable powders（WP） accounted for the largest portion at56.53%, followed by the soluble concentrate（SL） at 11.47%. And the emulsifiable concentrates（EC）,suspension concentrate（SC）, water dispersible granule（WG）, microemulsion（ME）, flowable concentrate for seed treatment（FS）, effervescent tablet（EB）, tablet（TA） and water dispersible powder for slurry seed treatment（WS） were 9.87%, 8.27%, 8.00%, 3.73%, 1.33%, 0.27%, 0.27% and 0.27%,respectively. These results showed that the predicted environmental concentration（PEC） of imidacloprid products ranged from 0.19 to 51.28 μg/L after applying different formulations of imidacloprid on rice in different scenes and seasons. In addition, the risk characterization results demonstrated that the risks of acute exposure to imidacloprid products to fish and invertebrates and that of chronic exposure to fish and primary producers were acceptable under existing registration conditions. However, there were potential chronic risks to Daphnia magna and Chironomus riparius as a result of only 13.58% of the simulated groups in which the risk quotient（RQ） was less than 1. These results suggested the currently imidacloprid products registered in China posed a certain risk to aquatic ecosystem according to the current registration application conditions. In the present study, it should be noted that the assessment method used to analyze the application model of all imidacloprid product formulations was relatively conservative, and the metabolite had not been analyzed because of its insufficient data. Therefore, these factors mentioned above made the evaluation results relatively conservative. [ABSTRACT FROM AUTHOR]

The Weihe River is the largest tributary of the Yellow River. The health of the river water ecosystem in the Weihe River Basin is closely related to the high-quality development of the Yellow River. Four times were carried out in the Weihe River Basin from 2011 to 2013. In the field sampling survey, a total of 77 sampling points were set up to collect information on fish, benthic animals, living algae and water environmental factors, analyze the characteristics of the aquatic ecosystem of the Weihe River Basin, and adopt The biological integrity index method evaluates the health of the aquatic ecosystem in the Weihe River Basin. A total of 51 species of fish, 116 species of benthic animals, and 248 species of living algae were collected in the Weihe River Basin. The environmental factor of the fish community structure in the Weihe River Basin is altitude, and the environmental factors that affect the structure of the benthic community are river width, electrical conductivity and hardness, which affect the structure of the algae community. The environmental factor is the width of the river. The results of the health assessment of the aquatic ecosystem show that the health status of benthic animals and living algae is better than that of fish, and more than 80% of the sampling points are in normal or above healthy water. The overall trend of the health evaluation results of the three biological water ecosystems is the same. The upper reaches of the Weihe River and the right bank tributaries, the source of the Jinghe River, and the middle reaches of the Beiluo River are in good health conditions. The middle and lower reaches of the river, most of the Jinghe River and the upper reaches of the Beiluo River are in poor health. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dongping Lake has comprehensive functions such as flood control, water transfer, tourism and irrigation. The aquatic ecosystem health status directly affects the water safety of the water receiving area. In this regard, on the basis of summarizing the research status of physical and chemical properties, eutrophication, ecological water level, community of aquatic organism and surface sediment in Dongping Lake, shortcomings were pointed out in the research. Five research contents for studying the ecological water level and the health of the aquatic ecosystem were determined for Dongping Lake, including historical data collection and systematic analysis of Dongping Lake water ecosystem, water ecosystem monitoring, ecological water level research, water ecosystem health research and water ecosystem ecological scheduling model and comprehensive repair technology research of the lake. The recent research objectives of the lake were put forward and the key scientific issues and research methods in the research process were clarified. [ABSTRACT FROM AUTHOR]

Zooplankton plays a mediating role in the food web of aquatic ecosystems, the stable carbon and nitrogen isotopes (δ13 C and δ15 N) of which have been widely used to study the utilization of food resources, material cycling pathways, and trophic relationships. The δ13 C and 8 N values of zooplankton have been used to predict primary productivity, sources and sinks of pollutants and environmental changes. To better use δ13 C and δ15 N of zooplankton as ecological and environmental indicators, it is particularly important to understand their temporal and spatial variations and the influencing factors. Based on related literature, we synthesized spatial and temporal variations in δ13 C and δ15 N of zooplankton in different aquatic ecosystems and taxa groups, and the use of δ13 C and δ15 N indicators for ecological processes and environmental changes. The δ13 C and δ15 N of zoo-plankton are largely affected by its food sources, and its stable isotope compositions are in turn affected by primary productivity and nitrogen sources. We proposed that the combination of δ13 C and δ15 N in zooplankton with transportation and transformation of emerging pollutants would form a multi-means, multi-disciplinary and multi-scale research direction in the fields of earth science and biology. [ABSTRACT FROM AUTHOR]

Phytoplankton is the most important biological component in the reservoir ecosystem, which could indicate the status of aquatic ecosystem due to its sensitive to environmental variation. To understand the application and difference between two methods of phytoplankton functional group classification, functional groups (FG) and morphology-based functional groups (MBFG), in indicating the changes of reservoir environment, we investigated water quality and phytoplankton in Qingshitan Reservoir monthly from March 2016 to February 2017. Two phytoplankton functional groups classifications (FG and MBFG) were used to analyze phytoplankton community composition, seasonal succession, and its driving factors. We compared the application and differences of two methods of functional group classifications in indicating environmental changes. The results showed that there were 109 species belonged to seven phylum, which could be classified into 17 FG or 5 MBFG functional groups. Results from both methods indicated that the reservoir was meso-eutrophic. The phytoplankton seasonal succession under 8 or 9 steps with FG or 8 steps with MBFG. Results from the redundancy analysis showed that the response of phytoplankton community reflected with FG to environmental variation was more sensitive than that with MBFG, especially in the response to the changes of pH and nitrate concentration. In conclusion, FG was more appropriate in describing community succession and exploring the relationship between phytoplankton and environment. [ABSTRACT FROM AUTHOR]

Methylmercury is the most toxic form among mercury compounds in the aquatic ecosystem, and poses health risks to organisms through the food chain.The effective control of methylation processes of mercury is an active research field in environmental chemistry and toxicology.Selenium(Se) has a significant suppression effect on the methylation processes of mercury(Hg).Therefore, it will be beneficial to the prevention and control of mercury contamination to clarify the speciation characteristic of mercury and the interaction mechanisms between mercury and selenium in the aquatic ecosystem.Mercury toxicity is closely associated with the levels of selenium in organisms, the interaction between Hg and Se are mainly embodied in the formation of insoluble compounds to contribute mercury demethylation or methylmercury directly ruled out by inhibition of biological a selenium related enzyme, which inhibits the toxic effect of mercury.In this paper, the speciation and distribution characteristics of mercury and selenium in the aquatic ecosystem and their interaction mechanisms were reviewed.Meanwhile, the reasonable addition of selenium compounds into water will be an effective way to inhibit the methylation processes of mercury in organisms.The development direction for the studies of interaction mechanisms between mercury and selenium and its physical effects in organisms were also reviewed.

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Methylmercury is the most toxic form among mercury compounds in the aquatic ecosystem, and poses health risks to organisms through the food chain. The effective control of methylation processes of mercury is an active research field in environmental chemistry and toxicology. Selenium (Se) has a significant suppression effect on the methylation processes of mercury (Hg). Therefore, it will be beneficial to the prevention and control of mercury contamination to clarify the speciation characteristic of mercury and the interaction mechanisms between mercury and selenium in the aquatic ecosystem. Mercury toxicity is closely associated with the levels of selenium in organisms, the interaction between Hg and Se are mainly embodied in the formation of insoluble compounds to contribute mercury demethylation or methylmercury directly ruled out by inhibition of biological a selenium related enzyme, which inhibits the toxic effect of mercury. In this paper, the speciation and distribution characteristics of mercury and selenium in the aquatic ecosystem and their interaction mechanisms were reviewed. Meanwhile, the reasonable addition of selenium compounds into water will be an effective way to inhibit the methylation processes of mercury in organisms. The development direction for the studies of interaction mechanisms between mercury and selenium and its physical effects in organisms were also reviewed. [ABSTRACT FROM AUTHOR]

Based on the investigation of the hydrology, water quality, periphytic algae, and habitat conditions of 20 hydrologic sections in the Tieling, Shenyang, and Panjin reaches of Liaohe River from June to August 2009, the indicators and their weights for the health assessment of aquatic ecosystem in the River were screened and determined by the method of principal component analysis, and the River's health assessment indicator system and health assessment standard system were constructed. The modified gray correlative degree method was also used to evaluate the aquatic ecosystem health condition at six sections of the River. Among the sections evaluated, three of them had a fair health level, two were worse or worst, and only one reached sub?health degree, suggesting that the aquatic ecosystem in the River was seriously degraded. Special attention should be paid to the ecological recovery of the river system, and comprehensive measures should be taken to control the River's water pollution. [ABSTRACT FROM AUTHOR]

Species coexistence depends on the comprehensive effects of biological properties and habitat heterogeneity. Based on a large-scale field survey (21°-35° N), we compared the differences on morphological and stoichiometric characteristics between the invasive aquatic species Alternanthera philoxeroides and the native co-occurring species Paspalum paspaloides , and examined the effects of environmental factors on such differences. The results showed that the coverage and importance value (IV) of A . philoxeroides were all significantly greater than P . paspa-loides (34.3% and 104.0%, respectively), whereas the height of P . paspaloides was significantly greater than A . philoxeroides (13.8%). Moreover, the total nitrogen concentration (TN) and N:P of A . philoxeroides were significantly greater than those of P . paspaloides (55.1% and 55.8%, respectively), whereas the total carbon concentration (TC) and C:N of P . paspaloides were significantly greater than those of A . philoxeroides (4.1% and 83.8%, respectively). A . philoxeroides coverage increased with the increases of longitude, and its abundance increased with the increases of water nitrate concentration and longitude, while its IV increased with the increases of water ammonium concentration. However, the coverage, abundance, and IV of P . paspaloides decreased with the increases of ammonium concentration. C:N of A . philoxeroides decreased with the increase of ammonium concentration. Increased mean annual temperature and mean annual precipitation increased C:N but decreased N:P of P . paspa-loides. The C:P of both species decreased with the increases of ammonium concentration and electrical conductivity. N:P of A . philoxeroides was little affected by environment. These results indicated that A . philoxeroides had greater coverage and N absorption capacity than P . paspaloides , and that enriched water nitrogen would aggravate the invasion of A . philoxeroides. Meanwhile, P . paspaloides improved its C-assimilate reserves and chose the growth competition strategy for resisting A . philoxeroides invasion under the superior hydrothermal conditions. Different responses to environmental changes contributed to their coexistence in aquatic ecosystem.

Zooplankton plays a mediating role in the food web of aquatic ecosystems, the stable carbon and nitrogen isotopes (δ 13 C and δ 15 N) of which have been widely used to study the utilization of food resources, material cycling pathways, and trophic relationships. The δ 13 C and δ 15 N values of zooplankton have been used to predict primary productivity, sources and sinks of pollutants and environmental changes. To better use δ 13 C and δ 15 N of zooplankton as ecological and environmental indicators, it is particularly important to understand their temporal and spatial variations and the influencing factors. Based on related literature, we synthesized spatial and temporal variations in δ 13 C and δ 15 N of zooplankton in different aquatic ecosystems and taxa groups, and the use of δ 13 C and δ 15 N indicators for ecological processes and environmental changes. The δ 13 C and δ 15 N of zooplankton are largely affected by its food sources, and its stable isotope compositions are in turn affected by primary productivity and nitrogen sources. We proposed that the combination of δ 13 C and δ 15 N in zooplankton with transportation and transformation of emerging pollutants would form a multi-means, multi-disciplinary and multi-scale research direction in the fields of earth science and biology.

Phytoplankton is the most important biological component in the reservoir ecosystem, which could indicate the status of aquatic ecosystem due to its sensitive to environmental variation. To understand the application and difference between two methods of phytoplankton functional group classification, functional groups (FG) and morphology-based functional groups (MBFG), in indicating the changes of reservoir environment, we investigated water quality and phytoplankton in Qingshitan Reservoir monthly from March 2016 to February 2017. Two phytoplankton functional groups classifications (FG and MBFG) were used to analyze phytoplankton community composition, seasonal succession, and its driving factors. We compared the application and differences of two methods of functional group classifications in indicating environmental changes. The results showed that there were 109 species belonged to seven phylum, which could be classified into 17 FG or 5 MBFG functional groups. Results from both methods indicated that the reservoir was meso-eutrophic. The phytoplankton seasonal succession under 8 or 9 steps with FG or 8 steps with MBFG. Results from the redundancy analysis showed that the response of phytoplankton community reflected with FG to environmental variation was more sensitive than that with MBFG, especially in the response to the changes of pH and nitrate concentration. In conclusion, FG was more appropriate in describing community succession and exploring the relationship between phytoplankton and environment.