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The monitoring of Poyang Lake water area and storage changes using remote sensing and satellite gravimetry techniques is valuable for maintaining regional water resource security and addressing the challenges of global climate change. In this study, remote sensing datasets from Landsat images (Landsat 5, 7, 8 and 9) and three Gravity Recovery and Climate Experiment (GRACE) and Gravity Follow-on (GRACE-FO) mascon solutions were jointly used to evaluate the water area and storage changes in response to global and regional climate changes. The results showed that seasonal characteristics existed in the terrestrial water storage (TWS) and water area changes of Poyang Lake, with nearly no significant long-term trend, for the period from April 2002 to December 2022. Poyang Lake exhibited the largest water area in June and July every year and then demonstrated a downward trend, with relatively smaller water areas in January and November, confirmed by the estimated TWS changes. For the flood (August 2010) and drought (September 2022) events, the water area changes are 3032 km2 and 813.18 km2, with those estimated TWS changes 17.37 cm and −17.46 cm, respectively. The maximum and minimum Poyang Lake area differences exceeded 2700 km2. The estimated terrestrial water storage changes in Poyang Lake derived from the three GRACE/GRACE-FO mascon solutions agreed well, with all correlation coefficients higher than 0.92. There was a significant positive correlation higher than 0.75 between the area and TWS changes derived from the two independent monitoring techniques. Therefore, it is reasonable to conclude that combined remote sensing with satellite gravimetric techniques can better interpret the response of Poyang Lake to climate change from the aspects of water area and TWS changes more efficiently. [ABSTRACT FROM AUTHOR]

Constructed from a dataset capturing the seasonal and annual water body distribution of the lower Qarqan River in the Taitma Lake area from 2017 to 2022, and combined with the meteorological and hydraulic engineering data, the spatial and temporal change patterns of the Taitma Lake watershed area were determined. Analyses were conducted using Planetscope (PS) satellite images and a deep learning model. The results revealed the following: ① Deep learning-based water body extraction provides significantly greater accuracy than the conventional water body index approach. With an impressive accuracy of up to 96.0%, UPerNet was found to provide the most effective extraction results among the three convolutional neural networks (U-Net, DeeplabV3+, and UPerNet) used for semantic segmentation; ② Between 2017 and 2022, Taitma Lake's water area experienced a rapid decrease, with the distribution of water predominantly shifting towards the east–west direction more than the north–south. The shifts between 2017 and 2020 and between 2020 and 2022 were clearly discernible, with the latter stage (2020–2022) being more significant than the former (2017–2020); ③ According to observations, Taitma Lake's changing water area has been primarily influenced by human activity over the last six years. Based on the research findings of this paper, it was observed that this study provides a valuable scientific basis for water resource allocation aiming to balance the development of water resources in the middle and upper reaches of the Tarim and Qarqan Rivers, as well as for the ecological protection of the downstream Taitma Lake. [ABSTRACT FROM AUTHOR]

Exploring the different characteristics of water status at different time scales is essential for the understanding of the complex hydrological processes in lakes connected to rivers. Taking Dongting Lake, a large-scale lake connected to the Yangtze River, as an example, this study employed wavelet analysis and multiple models to explore the temporal characteristics of water area, level, and flow and the water level–area and flow–area correlations from 2000 to 2021 on annual, seasonal, and monthly scales. The results show that the interannual variations in annual, seasonal, and monthly water area anomalies demonstrated rather consistent overall trends, but there were differences in the variation ranges at different temporal scales. The dominant amplitudes for annual and seasonal area anomalies were close, while for monthly anomalies, they were sometimes much larger. The dominant amplitudes of the water level and flow anomalies generally followed the order annual < seasonal < monthly. The water level–area and flow–area correlations are strongest at Chenglingji station and on the seasonal scale. This study provides a multiscale perspective on hydrological conditions and will support the management of water resources and the prevention of drought and flood disasters. [ABSTRACT FROM AUTHOR]

Copyright of Nuclear Safety is the property of Nuclear & Radiation Safety Center 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 Home Economics of Japan is the property of Japan Society of Home Economics 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 monitoring of Poyang Lake water area and storage changes using remote sensing and satellite gravimetry techniques is valuable for maintaining regional water resource security and addressing the challenges of global climate change. In this study, remote sensing datasets from Landsat images (Landsat 5, 7, 8 and 9) and three Gravity Recovery and Climate Experiment (GRACE) and Gravity Follow-on (GRACE-FO) mascon solutions were jointly used to evaluate the water area and storage changes in response to global and regional climate changes. The results showed that seasonal characteristics existed in the terrestrial water storage (TWS) and water area changes of Poyang Lake, with nearly no significant long-term trend, for the period from April 2002 to December 2022. Poyang Lake exhibited the largest water area in June and July every year and then demonstrated a downward trend, with relatively smaller water areas in January and November, confirmed by the estimated TWS changes. For the flood (August 2010) and drought (September 2022) events, the water area changes are 3032 km2 and 813.18 km2, with those estimated TWS changes 17.37 cm and −17.46 cm, respectively. The maximum and minimum Poyang Lake area differences exceeded 2700 km2. The estimated terrestrial water storage changes in Poyang Lake derived from the three GRACE/GRACE-FO mascon solutions agreed well, with all correlation coefficients higher than 0.92. There was a significant positive correlation higher than 0.75 between the area and TWS changes derived from the two independent monitoring techniques. Therefore, it is reasonable to conclude that combined remote sensing with satellite gravimetric techniques can better interpret the response of Poyang Lake to climate change from the aspects of water area and TWS changes more efficiently.

Constructed from a dataset capturing the seasonal and annual water body distribution of the lower Qarqan River in the Taitma Lake area from 2017 to 2022, and combined with the meteorological and hydraulic engineering data, the spatial and temporal change patterns of the Taitma Lake watershed area were determined. Analyses were conducted using Planetscope (PS) satellite images and a deep learning model. The results revealed the following: ① Deep learning-based water body extraction provides significantly greater accuracy than the conventional water body index approach. With an impressive accuracy of up to 96.0%, UPerNet was found to provide the most effective extraction results among the three convolutional neural networks (U-Net, DeeplabV3+, and UPerNet) used for semantic segmentation; ② Between 2017 and 2022, Taitma Lake’s water area experienced a rapid decrease, with the distribution of water predominantly shifting towards the east–west direction more than the north–south. The shifts between 2017 and 2020 and between 2020 and 2022 were clearly discernible, with the latter stage (2020–2022) being more significant than the former (2017–2020); ③ According to observations, Taitma Lake’s changing water area has been primarily influenced by human activity over the last six years. Based on the research findings of this paper, it was observed that this study provides a valuable scientific basis for water resource allocation aiming to balance the development of water resources in the middle and upper reaches of the Tarim and Qarqan Rivers, as well as for the ecological protection of the downstream Taitma Lake.

Exploring the different characteristics of water status at different time scales is essential for the understanding of the complex hydrological processes in lakes connected to rivers. Taking Dongting Lake, a large-scale lake connected to the Yangtze River, as an example, this study employed wavelet analysis and multiple models to explore the temporal characteristics of water area, level, and flow and the water level–area and flow–area correlations from 2000 to 2021 on annual, seasonal, and monthly scales. The results show that the interannual variations in annual, seasonal, and monthly water area anomalies demonstrated rather consistent overall trends, but there were differences in the variation ranges at different temporal scales. The dominant amplitudes for annual and seasonal area anomalies were close, while for monthly anomalies, they were sometimes much larger. The dominant amplitudes of the water level and flow anomalies generally followed the order annual < seasonal < monthly. The water level–area and flow–area correlations are strongest at Chenglingji station and on the seasonal scale. This study provides a multiscale perspective on hydrological conditions and will support the management of water resources and the prevention of drought and flood disasters.

The paper presents an analysis of long-term dynamics and current trends in the hydrochemistry of the Pavlovsky Reservoir by 10 chemical indicators at seven water intake points. The choice of 10 chemical elements was justified in previous studies mentioned in the paper. This approach allows using the observation data of the Bashkir FSBI (Federal State Budgetary Institution Bashkir Hydrometeorology and Environmental Monitoring Department), previous studies conducted in 1986–88 and in 2000 and the results of the present research (2018–2019) making it possible to track the dynamics of changes in the hydrochemical composition of water over 30 years (from 1986 to 2018). It was revealed that throughout the reservoir, from its beginning to the upper reaches, the content of Sr2+, Mn2+ and petroleum products in the water decreases; Zn2+, Hg2+, phenols and organic substances increase; Fe total (Fe2+ + Fe3+), P total are evenly distributed (according to PO43-), Cu2+. The study of the features of the long-term dynamics of the hydrochemical indicators of the Pavlovsky Reservoir allows for determining trends in the state of the ecosystem of the water body and proposes measures to preserve the operational properties of the reservoir. HIGHLIGHTS Studying the modern processes of chemical hydrology of the Pavlovsky Reservoir.; The long-term dynamics of the hydrochemical indicators of the Pavlovsky Reservoir.; Maximum, minimum and average values of the concentrations of Fe, Mn, Cu, Sr, Zn, etc.; Priority ways to improve the reservoir water quality.;

The Neva Bay is a body of water located between the delta of the Neva River and Kotlin Island. The goal of the study was to develop a method for numerical modeling of the shallow water equation in the Neva Bay, based on the finite element method. To achieve this goal, we solved a number of tasks. First, we selected characteristic periods in the history of the Neva Bay and formed numerical modeling options while determining boundary conditions. Secondly, we determined the geometric characteristics of the computational domain for modeling options and formed a finite element mesh for each of the options. Then, we found a numerical solution of hydrodynamic problems in terms of determining values of current velocity vectors. Finally, we conducted a comparative analysis of the results of solving the hydrodynamic problem of the structure of currents in the Neva Bay in different periods of history. The changes in the velocity field occurred because of the construction of the fairway and the dams for the Complex of flood protection structures (CFPS) in St. Petersburg. Today there is practically no water flow south of the Sea Canal. Water exchange between the Neva Bay and the Gulf of Finland is carried out due to culvert structures in the northern part of the CFPS and navigation facilities. The average flow of the Neva River during the calculation period did not change and was about 2500 m3/s (depends on the water level in Lake Ladoga); an increase in speeds occurs north of the Sea Canal.

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Monitoring water surface areas plays an extremely important role, especially for river and reservoir, lake systems that are significant for irrigation, hydropower and ecosystems etc. In the Tri An reservoir area, the main water source for Dong Nai province, and also where many people live in 4 districts of VinhCuu, DinhQuan, Thong Nhat and TrangBom. However, in the dry season of 2023, the weather became hot and dry with little rain due to the influence of the El Nino phenomenon. The water level of Tri An Lake has dropped to a record low in the past 12 years. Based on Sentinel 1 images and threshold method, this study conducted water surface extraction from January May 2023 of Tri An lake. The results showed that, from January to May 2023, the water surface area decreased from 26,270.97 hectares to 10,059.87 hectares. The most obvious decrease in water surface area was in Phu Ly and Ma Da communes (VinhCuu district) and the La Nga bridge section. This study has been a demonstration of the impact of global climate change on water resources, providing a basis for environmental resource management.

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower 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.)

The area fluctuation of lakes directly affects the stability of the surrounding ecological environment. Research on the area evolution of lakes and the driving factors affecting it plays an important role in sustainable water resource management. In this study, Hulun Lake, located in the Hulunbuir grassland, was taken as the research object. Based on remote sensing images of the Hulun Lake area from 1986 to 2020, MNDWI interpretation was used to obtain the change law of lake surface area over a long time frame. Combined with natural factors and anthropogenic factors, Pearson correlation analysis and principal component analysis were used to analyze the driving force. The results showed that (1) in the past 35 years, the water surface area of Hulun Lake has decreased significantly. The dynamic change in water area could be divided into four stages. The areas with dramatic changes in water area are distributed mainly in the northeast and south of Hulun Lake. (2) In terms of natural factors, the meteorological factors based on evaporation and relative humidity, the runoff of rivers entering the lake, and the vegetation with medium-high coverage and medium-low coverage had significant effects. In terms of anthropogenic factors, the population had the most significant impact. The artificial water diversion project had different degrees of influence on the response of the Hulun Lake area change to natural factors. (3) Anthropogenic factors were the main driving force causing the rapid change in the Hulun Lake area from 2000 to 2016, explaining 48% of the change in the Hulun Lake area. These research results can provide a scientific basis for the development and utilization of water resources and sustainable development in the Hulun Lake area. [ABSTRACT FROM AUTHOR]

Expected global climate change is allegedly becoming more intense, and the impacts on water resources are being tracked in various hydroclimatic regimes. The present research investigates a hydrologically important area of Greece, where four natural lakes are concentrated. It aims to quantify any potential long-term trends in lake water area, precipitation, and temperature timeseries. Water area timeseries spanning four decades are estimated by the mNDWI from Landsat satellite imagery and used as an index of each lake's water storage. Precipitation and temperature measurements are obtained from the open access datasets Hydroscope and ERA5-Land, respectively. All of the timeseries were tested seasonally and annually with the Pettitt and Mann–Kendal tests for statistically significant breakpoints and trends detection. No timeseries analysis resulted in a statistically significant (at 0.05 or 0.1 levels) annual or seasonal trend. The hydroclimatic regime over the past forty years in western Greece is found to have been relatively stable. Land use was also assessed to have been relatively unchanging, converging to the overall stability of the local water regime. However, the findings of this research should not be interpreted as a reassurance against climate change, but as a call to further research for the detailed regional and local assessment of climate change and hydroclimatic variability with acknowledged statistical approaches. [ABSTRACT FROM AUTHOR]

Lakes are an important part of the Earth's surface. Poyang Lake is China's largest freshwater lake with complex hydrological relationships and unique rhythmic changes. There is no systematic understanding of the relationship between lake watershed area and river–lake connectivity. In this study, using remote sensing imagery, hydrological data, meteorological data, and land use surveys, we investigated changes in the Poyang Lake water area from 1977–2021. In addition, we examined the relationship between the lake water area and potential impact factors and analyzed the influence of river–lake interactions on the lake water area. The results showed that the water area of Poyang Lake decreased during the study period. River runoff and sediment load changes in the Poyang Lake basin are the main factors affecting the lake water area. Additionally, the Three Gorges Dam water impoundment situated in the upper reaches of the Yangtze River weakened and eliminated the block and reverse flow of the Yangtze River into the Poyang Lake, causing the water area to decrease toward the end of the flood season in 2005 and in the dry season in 2003. Changes in the lakebed elevation caused by sedimentation and anthropogenic activities have also accelerated the shrinkage of the water area. Overall, the results of this study indicate that variations in the river–lake interactions are the primary cause of the significant changes observed in the Poyang Lake water area in the last five decades. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. 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 explore the dynamic changes regarding water landscape patterns on the Jianghan Plain and their respective driving factors from 2000 to 2020, research was carried out using transition matrix analysis, spatial autocorrelation analysis, landscape metrics analysis and redundancy analysis, applying both GIS and multivariate statistics techniques. Results show that the surface area of water on the Jianghan Plain has decreased by 36% from 2000 to 2020, as a result of farmlands being reclaimed for urbanized purposes, and water-areas then being reclaimed for use as farmlands. Indices of Global Moran′s I and Anselin Local Moran′s I show a distinct change, and water- area edge density have dropped dramatically. Spatial aggregation and connectivity of water-area of some regions such as the Sihu catchment have shown a significant decrease. 45. 8% of the changes to the water landscape patterns are a result of precipitation, temperature, and farmlands and artificial surfaces. Of these, precipitation and temperature factors only show a negligible contribution to the overall changes, the contiguous cultivated land has proven to be one of the main causes of the reduction in water landscape areas, while artificial surfaces show a large and direct contribution to the fragmentation of water bodies. During the last two decades, the changes to the water landscape area on the Jianghan Plain is evident, both shape complexity and connectivity have decreased along with a trend towards fragmentation, cultivated lands and artificial surfaces used for agricultural activities and urbanized purposes have severely affected water landscape patterns. [ABSTRACT FROM AUTHOR]

Copyright of Nuclear Safety is the property of Nuclear & Radiation Safety Center 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.)

Water area and waterweed coverage are the key environmental factors for ecological breeding of Eriocheir sinensis in ponds. In order to explore the effects of above two factors on the growth of E. sinensis, three groups of experiments were set up: low coverage small area (C1S1), high coverage small area (C2S1), and high coverage large area (C2S2), and water environmental factors and the growth of E. sinensis were monitored. The results showed that the dissolved oxygen of ponds with different waterweed coverage was significantly different (p < 0.05), and the phosphate in ponds changed significantly from July to October (p < 0.05). The correlation analysis showed that NH3-N and pH were significantly positively correlated (p < 0.05). At the same time, there was a significant negative correlation between NH3-N and DO, H3PO4 and pH (p < 0.05). Further analysis of the relationship between surface area, waterweed coverage and environmental factors revealed that the surface area and waterweed coverage were closely related to NH3-N, H3PO4 and DO. From July to October, the differences in morphology and weight of E. sinensis in different ponds became more and more significant. In terms of growth rate, C1S1 with a small area and low coverage had a downward trend, while C2S1 and C2S2 were the opposite. In the final stage of the experiment, C2S2 had the highest yield (0.1311 kg/m2), and C1S1 had the lowest yield (0.0600 kg/m2). Then, the ponds with high waterweed coverage and large area can bring better benefits. [ABSTRACT FROM AUTHOR]

Ferry service is a transport system of regular routes which links areas separated by water bodies. Sometimes ferries are the only connection of an island and the mainland which is not rare in the Baltic Sea. A typical example of this is the island of Saaremaa. Ferry service is the backbone of cargo and passenger traffic in the Baltic Sea region. This article aims to describe the spatial structure of the ferry service in the Baltic Sea. To this end, a statistical database on 101 ferry routes has been built with passenger and car traffic on each being calculated with an original methodology, which in its turn can be applied in analysing the spatial structure and traffic of ferry services in other regions. Baltic ferries account for over half of all European ferry-borne car and passenger traffic. The Baltic stands out as a region with exceptionally long ferry routes which sustain timber exports. The main cargo shipping country in the region is Sweden.

The area fluctuation of lakes directly affects the stability of the surrounding ecological environment. Research on the area evolution of lakes and the driving factors affecting it plays an important role in sustainable water resource management. In this study, Hulun Lake, located in the Hulunbuir grassland, was taken as the research object. Based on remote sensing images of the Hulun Lake area from 1986 to 2020, MNDWI interpretation was used to obtain the change law of lake surface area over a long time frame. Combined with natural factors and anthropogenic factors, Pearson correlation analysis and principal component analysis were used to analyze the driving force. The results showed that (1) in the past 35 years, the water surface area of Hulun Lake has decreased significantly. The dynamic change in water area could be divided into four stages. The areas with dramatic changes in water area are distributed mainly in the northeast and south of Hulun Lake. (2) In terms of natural factors, the meteorological factors based on evaporation and relative humidity, the runoff of rivers entering the lake, and the vegetation with medium-high coverage and medium-low coverage had significant effects. In terms of anthropogenic factors, the population had the most significant impact. The artificial water diversion project had different degrees of influence on the response of the Hulun Lake area change to natural factors. (3) Anthropogenic factors were the main driving force causing the rapid change in the Hulun Lake area from 2000 to 2016, explaining 48% of the change in the Hulun Lake area. These research results can provide a scientific basis for the development and utilization of water resources and sustainable development in the Hulun Lake area.

Mapping water bodies with a high accuracy is necessary for water resource assessment, and mapping them rapidly is necessary for flood monitoring. Poyang Lake is the largest freshwater lake in China, and its wetland is one of the most important in the world. Poyang Lake is affected by floods from the Yangtze River basin every year, and the fluctuation of the water area and water level directly or indirectly affects the ecological environment of Poyang Lake. Synthetic Aperture Radar (SAR) is particularly suitable for large-scale water body mapping, as SAR allows data acquisition regardless of illumination and weather conditions. The two-satellite Sentinel-1 constellation, providing C-Band SAR data, passes over the Poyang Lake about five times a month. With its high temporal-spatial resolution, the Sentinel-1 SAR data can be used to accurately monitor the water body. After acquiring all the Sentinel-1 (1A and 1B) SAR data, to ensure the consistency of data processing, we propose the use of a Python and SeNtinel Application Platform (SNAP)-based engine (SARProcMod) to process the data and construct a Poyang Lake Sentinel-1 SAR dataset with a 10 m resolution. To extract water body information from Sentinel-1 SAR data, we propose an automatic classification engine based on a modified U-Net convolutional neural network (WaterUNet), which classifies all data using artificial sample datasets with a high validation accuracy. The results show that the maximum and minimum water areas in our study area were 2714.08 km 2 on 20 July 2020, and 634.44 km 2 on 4 January 2020. Compared to the water level data from the Poyang gauging station, the water area was highly correlated with the water level, with the correlation coefficient being up to 0.92 and the R 2 from quadratic polynomial fitting up to 0.88; thus, the resulting relationship results can be used to estimate the water area or water level of Poyang Lake. According to the results, we can conclude that Sentinel-1 SAR and WaterUNet are very suitable for water body monitoring as well as emergency flood mapping. [ABSTRACT FROM AUTHOR]

Inland water resources are facing increasing quantitative and qualitative pressures, deriving from anthropogenic causes and the ongoing climate change. The monitoring of reservoirs is essential for sustainable management and preparation against water scarcity and extreme events, such as droughts. This research, relying on the Sentinel-2 and 3 missions, attempts to demonstrate the efficiency of combining remotely sensed water level and water area estimations, in order to estimate the water storage variation of Yliki reservoir. The case study is conducted in one of the few sufficiently monitored reservoirs in Greece, enabling a direct comparison of the proposed methodology results with in situ observations. Moreover, this research work proposes a weekly time interval for pairing level and area estimations, instead of shorter time intervals. The results strongly demonstrate the efficiency of remote sensing in the production of empirical level–area–storage (L–A–S) curves. Correlation to in situ monitored storage- and satellite-derived water level, area stand for 98.81% and 99.27% respectively. Water storage variation is estimated and compared to the observed time series, resulting in an RMSE of 1.28% of the reservoir capacity and a correlation of 96.14%. The empirical L–S relationship underestimates storage, while the A–S relationship overestimates storage when compared to the existing L–A–S curve. [ABSTRACT FROM AUTHOR]

Lake Issyk-Kul is the largest alpine lake in arid Central Asia. In recent years, the lake has become a subject of special concern due to the dramatic fluctuations in its water level. In this study, the long-term continuous changes in the water level of Lake Issyk-Kul were derived from hydro-meteorological stations, CryoSat-2, and ICESat-2 satellites. Changes in area were analyzed by the Joint Research Centre (JRC) Global Surface Water (GSW) dataset based on the Google Earth Engine and the variations in water volume were estimated by an empirical formula. The results indicate that the water level of Lake Issyk-Kul fluctuated between 1606.06 m and 1608.32 m during 1958–2020, showing a slight decrease of 0.02 m/year on average. The water level first experienced a significant decreasing trend of 0.05 m/year from 1958 to 1998, and then began to rise rapidly by 0.10 m/year during 1998–2006, followed by a fluctuating decline after 2006. The area of Lake Issyk-Kul exhibited a downward trend before 1998, then a rapid expansion during 1998–2006, and short-term fluctuations in decline thereafter. Meanwhile, changes in water volume of Lake Issyk-Kul followed a similar pattern of variations in water level and area. According to comprehensive analyses, the continuous downward trend of the water level before 1998 was primarily affected by substantial anthropogenic water consumption in the basin. However, since the 21st century, the increases in precipitation and glacier meltwater and the reduced water consumption have collectively facilitated the short-term recovery of Lake Issyk-Kul in water level, area, and water volume. [ABSTRACT FROM AUTHOR]

Introduction: Artificial islands for new construction and works in a dry environment are created in water areas by installing enclosures, which allow buildings to remain rigid and stable and withstand the influence of climatic factors. Purpose of the study: We aim to develop a method for the construction of low-rise buildings in the coastland and water areas with the least labor effort required to erect buildings and ensure their safe operation. Methods: In the course of the research, we have performed theoretical studies in the field of experimental construction and analyzed the results of Russian and foreign scientific research related to the construction of buildings in water areas. Results: We have examined methods for the construction of waterproof enclosures in water areas that make it possible to erect buildings in a dry environment in open water areas with unstable wave conditions. Such methods reduce labor efforts, decrease the term of construction, and improve performance indicators.

Expected global climate change is allegedly becoming more intense, and the impacts on water resources are being tracked in various hydroclimatic regimes. The present research investigates a hydrologically important area of Greece, where four natural lakes are concentrated. It aims to quantify any potential long-term trends in lake water area, precipitation, and temperature timeseries. Water area timeseries spanning four decades are estimated by the mNDWI from Landsat satellite imagery and used as an index of each lake’s water storage. Precipitation and temperature measurements are obtained from the open access datasets Hydroscope and ERA5-Land, respectively. All of the timeseries were tested seasonally and annually with the Pettitt and Mann–Kendal tests for statistically significant breakpoints and trends detection. No timeseries analysis resulted in a statistically significant (at 0.05 or 0.1 levels) annual or seasonal trend. The hydroclimatic regime over the past forty years in western Greece is found to have been relatively stable. Land use was also assessed to have been relatively unchanging, converging to the overall stability of the local water regime. However, the findings of this research should not be interpreted as a reassurance against climate change, but as a call to further research for the detailed regional and local assessment of climate change and hydroclimatic variability with acknowledged statistical approaches.

Lakes are an important part of the Earth’s surface. Poyang Lake is China’s largest freshwater lake with complex hydrological relationships and unique rhythmic changes. There is no systematic understanding of the relationship between lake watershed area and river–lake connectivity. In this study, using remote sensing imagery, hydrological data, meteorological data, and land use surveys, we investigated changes in the Poyang Lake water area from 1977–2021. In addition, we examined the relationship between the lake water area and potential impact factors and analyzed the influence of river–lake interactions on the lake water area. The results showed that the water area of Poyang Lake decreased during the study period. River runoff and sediment load changes in the Poyang Lake basin are the main factors affecting the lake water area. Additionally, the Three Gorges Dam water impoundment situated in the upper reaches of the Yangtze River weakened and eliminated the block and reverse flow of the Yangtze River into the Poyang Lake, causing the water area to decrease toward the end of the flood season in 2005 and in the dry season in 2003. Changes in the lakebed elevation caused by sedimentation and anthropogenic activities have also accelerated the shrinkage of the water area. Overall, the results of this study indicate that variations in the river–lake interactions are the primary cause of the significant changes observed in the Poyang Lake water area in the last five decades.

. In this study, the catchment area of Taihu Lake, China, was divided into four parts: water area, farmland area, construction land and vegetation area, and the total amount of atmospheric nitrogen deposition from the catchment area into the Taihu Lake was estimated. The results showed that the total nitrogen deposition from the water area, farmland, urban construction land and vegetation area into the water were 38667.5 t, 124596.1 t, 52653.2 t and 11107.8 t, respectively. The atmospheric nitrogen deposition entering into water was 227024.6 t eventually, accounting for 80.5% of total atmospheric nitrogen deposition, which has exceeded the nitrogen content of agricultural non-point source pollution, industrial sewage, domestic sewage and other exogenous pollution. Nitrogen deposition in farmland area is the main source of entering Taihu Lake. Atmospheric nitrogen deposition may be the main pollution source into the Taihu basin. Atmospheric nitrogen deposition plays an important role in the input of exogenous nitrogen in Taihu Lake, which is an important source of nitrogen and plays an important role in eutrophication. It is recommended to take necessary measures to control atmospheric nitrogen deposition, for example, reduce energy-intensive industries, build buffer strips, ecological ditches, and three- dimensional greening. [ABSTRACT FROM AUTHOR]

Based on the long-term Landsat remote sensing data, the dynamic changes in the water area of Chahannaoer from 1986 to 2020 were analyzed, and the influencing factors of lake changes were analyzed combined with meteorological data and human factors. The results show that in the past 35 years, the water area of Chahannaoer tended to reduce obviously on the whole; annual average evaporation and annual average relative humidity gradually decreased, and annual average temperature, annual average precipitation, and annual average wind speed increased. Precipitation and relative humidity were significantly positively correlated with water area; temperature and average wind speed were negatively correlated with water area, but the correlation was not significant; there was a weak correlation between evaporation and water area. Precipitation and relative humidity were the main climatic factors affecting the change of water area in Chahannaoer. [ABSTRACT FROM AUTHOR]

The research aims to develop a fluid dynamic learning video-based contextual in water areas that valid and practical. This research is a development study using the Rowntree model, which consists of planning, development, and evaluation stages. The evaluation phase uses the Tessmer evaluation only to the small group evaluation stage. The one to one and small group evaluation stages will be carried out at SMA Negeri 1 Air Saleh in the even semester 2018/2019. Data collected through a walkthrough and questionnaire. The data is then analyzed by determining the mean percentage then converted to get the conclusion of validity and practicality of the video developed. The research conducted concluded that a fluid dynamic learning video-based contextual in water areas have been successfully developed with a percentage of 94% and very practical with a percentage of 87%, making it feasible to use. The product developed can then be used by the teacher to teach the concept of dynamic fluid, especially in schools in water areas, so that students can understand the concept of dynamic fluid based on the surrounding environment.

The problems of studying the negative factors of oil and gas activity in the waters of the North-Eastern Caspian Sea are presented. Despite the active anthropogenic activity, the specificity of hydrocarbon pollution in this part of the water area is poorly understood. The approaches to the analysis of the qualitative composition and identification of sources of polycyclic aromatic hydrocarbons (PAHs) pollution based on the indicator ratios of kinetic and thermodynamic isomers are presented. These approaches make it possible to identify the source of pollution, but a full assessment requires taking into account the seasonal dynamics of the sta- tus of aquatic systems. Estimates of the migration features of PAHs and their definitions in the aqueous phase are given. The problems of transition and the study of polyarenes to bottom sediments are assessed. The issues of the degradation of PAH and oil products in the aquatic systems of the region are considered, recommendations are given to improve the development of the research base of the reviewed topics.

Water area and waterweed coverage are the key environmental factors for ecological breeding of Eriocheir sinensis in ponds. In order to explore the effects of above two factors on the growth of E. sinensis, three groups of experiments were set up: low coverage small area (C1S1), high coverage small area (C2S1), and high coverage large area (C2S2), and water environmental factors and the growth of E. sinensis were monitored. The results showed that the dissolved oxygen of ponds with different waterweed coverage was significantly different (p < 0.05), and the phosphate in ponds changed significantly from July to October (p < 0.05). The correlation analysis showed that NH3-N and pH were significantly positively correlated (p < 0.05). At the same time, there was a significant negative correlation between NH3-N and DO, H3PO4 and pH (p < 0.05). Further analysis of the relationship between surface area, waterweed coverage and environmental factors revealed that the surface area and waterweed coverage were closely related to NH3-N, H3PO4 and DO. From July to October, the differences in morphology and weight of E. sinensis in different ponds became more and more significant. In terms of growth rate, C1S1 with a small area and low coverage had a downward trend, while C2S1 and C2S2 were the opposite. In the final stage of the experiment, C2S2 had the highest yield (0.1311 kg/m2), and C1S1 had the lowest yield (0.0600 kg/m2). Then, the ponds with high waterweed coverage and large area can bring better benefits.

We report an essential result of offshore exploration, that is, the discovery of a new oil- bearing region in the eastern part of the Pechora Sea shelf. Large oil fields, that is, the Prirazlomnoye, Varandey-more, Medyn-more, and Dolginskoye fields, have been discovered. The explored reserves and resources of hydrocarbons suggest that a new oil-producing region will be formed on the Pechora Sea shelf in the near future. According to the State Balance, the total initial raw oil resources in the Pechora Sea amount to 3273.2 million tons. The main purpose of our work is to draw attention to the problem of accelerating the research of the promising objects on the Pechora Sea shelf and to the additional exploration of the discovered deposits in the Ordovician–Lower Frasnian oil and gas megacomplex in the Varandey–Adzva structural zone (VASZ). The disproportion between the plans for the development of the fuel and energy complex, its resource availability, and the rate of replenishment of the mineral resource base of hydrocarbons on the Pechora Sea shelf may cause serious problems for the energy safety of the country. The further development of the large oil production cluster on the shelf of the Pechora Sea is primarily associated with the prospecting and development of hydrocarbon resources of the relatively deep-lying oil and gas bearing predominantly carbonate Ordovician–Lower Frasnian megacomplex (MC). This complex occurs on the shelf of VASZ and adjacent areas, especially at the Prirazlomnoye and Medyn-more fields. [ABSTRACT FROM AUTHOR]

The ecological and geographical regularities of the spatial differentiation of the fauna of birds and mammals in the seas of northeastern Russia were studied at the end of the winter period of 1987–1988. The aerial surveys covered the Bering, Chukchi, and East Siberian Seas and the eastern part of the Laptev Sea. Mammals are ecologically associated with open sea areas, sea ice, continental and island coasts, and mainland tundra. Wintering flocks of birds are formed by species of inland mountain streams; species that are common circumpolarly in the Holarctic tundra; and marine species of the continental and island coasts of the North Pacific and the Arctic Ocean, including high-latitude endemics. Seven species of mammals and 23 species of birds have been recorded. There are 22 bird species recorded exclusively in the Bering Sea (24% of the marine avifauna of the Russian Far East). In terms of the number of species represented (n = 9), the prevalence is held by auks, which are very characteristic of the avifauna of the subpolar marine areas of the Palaearctic. Mammals have been regularly recorded in both the Arctic Ocean and the Pacific research sector. The winter fauna of mammals in the seas of northeastern Russia, which is dominated in terms of the number of species by pinnipeds and cetaceans, makes up 23% of the total mammalian fauna of this region. In the Bering Sea, three areas of concentration of wintering birds have been identified: in the southeast of Chukotka, southeast of Cape Navarin, and south of the Island of St. Lawrence. The maximum density of the bird population (21.8 ind./km2) is in young ice and ice of primary formation—where there are many forage polynyas. The bird population of all types of ice is numerically dominated by fulmar and thin-billed and thick-billed guillemots. Most of the marine mammals are observed on the openings in the contact zones of different types of ice or in the ice openings of autumn formation. Clusters are formed by polar bears near the Wrangel Island, by beluga whales to the east and northeast of Cape Navarin, and by walruses to the south of it. The stability of winter spatial groups of walrus and polar bears in the Arctic Ocean, which annually demonstrated similar levels of abundance, has been established. Winter aerial surveys show that beluga whales and humpback whales are not found north of the Bering Strait, and polar bears are almost never found outside the Arctic Basin. [ABSTRACT FROM AUTHOR]

Hongyashan Reservoir is located in northwestern China where water resources are lacking. Reservoirs are an important support for the ecosystem in this region. Analyzing the changes in the area of the reservoir can effectively help Minqin County Government to make overall plans for water ecological protection and restoration as well as rational use of water resources and can also provide support for its decision - making. Through the extraction and analysis of the water area and vegetation coverage of the Landsat series data and GF -2 data from 2000 to 2019 and in combination with the surrounding meteorological data and the collection of local data' the authors comprehensively analyzed the influencing factors of the water area change and explored the spatial and temporal changes of the water area as well as the driving force. The results show that' on the whole, the water area of Hongyashan Reservoir has continued to increase in the past 20 years, the total area has increased by 8.98 km2, and the area change rate is as high as 42. 6%, and that, in terms of monthly changes, the change in water area has an inverted "normal distribution" curve. The trend is that the wet season is mainly concentrated in March and September - October in the spring and autumn seasons, and the dry season is mainly concentrated in June in the summer. In terms of interannual variability' the water area is greatly affected by the seasons, so it is divided into spring. Summer. autumn and winter. Interannual analysis shows that the water area in spring and winter continues to rise. with average annual growth rates of 5. 03% and 5. 22%, the lowest average annual growth rate in autumn is only 2. 42%. and the average annual growth rate of summer water area is 22. 19%. which is the season with the largest variation amplitude, exhibiting "V" fluctuation and rising. According to the meteorological data such as temperature, precipitation and evaporation, the correlation analysis of vegetation coverage and water area, and the analysis of related hydrological data, the following conclusions can be drawn: the direct driving forces are the change in precipitation, the increasing project expansion, and the change of runoff into the reservoir, whereas the indirect driving forces include changes in temperature, changes in vegetation coverage, the industrial, agricultural and domestic water use, and the restoration of the ecological environment. [ABSTRACT FROM AUTHOR]

【Objective】It is of great significance to elucidate the response of soil salinity to water area changes in the crisscross of lakeside hidden vegetation and zonal vegetation, and to monitor soil salinity regularly in the crisscross of lakeside hidden vegetation and zonal vegetation, and to grasp the change process of water level in Aibi lake in time. 【Method】Based on 6 Landsat remote sensing images from 1995 to 2019, taking Aibi lake in Xinjiang as the target area, the remote sensing technology was used to extract the water area and soil salt content information of Aibi lake.【Result】(i) Under the influence of climate and human factors, the water area of Aibi lake expanded first and then decreased from 523.40 km~2 to 724.90 km~2 and then to 437.37 km~2 from 1995 to 2019.(ii) Based on the analysis of the temporal and spatial changes of salinization around Aibi lake, from 1995 to 2019, the salinization of lakeside soil changed obviously in time and space, and the salinization of lakeside soil increased in the south and southeast of the study area, and the salinization of lakeside soil gradually shifted to the center of the lake.(iii) Through the comparative study of 1995-2000 and 2005-2010, it is found that the soil salt index in the crisscross of hidden vegetation and zonal vegetation increased and decreased with the expansion of the area of Aibi lake.【Conclusion】Based on the analysis of the relationship between the area of Aibi lake and the soil salinity in the study area during the past 24 years, it was found that the salinity index changed significantly in the southeastern crisscross. [ABSTRACT FROM AUTHOR]

Mapping water bodies with a high accuracy is necessary for water resource assessment, and mapping them rapidly is necessary for flood monitoring. Poyang Lake is the largest freshwater lake in China, and its wetland is one of the most important in the world. Poyang Lake is affected by floods from the Yangtze River basin every year, and the fluctuation of the water area and water level directly or indirectly affects the ecological environment of Poyang Lake. Synthetic Aperture Radar (SAR) is particularly suitable for large-scale water body mapping, as SAR allows data acquisition regardless of illumination and weather conditions. The two-satellite Sentinel-1 constellation, providing C-Band SAR data, passes over the Poyang Lake about five times a month. With its high temporal-spatial resolution, the Sentinel-1 SAR data can be used to accurately monitor the water body. After acquiring all the Sentinel-1 (1A and 1B) SAR data, to ensure the consistency of data processing, we propose the use of a Python and SeNtinel Application Platform (SNAP)-based engine (SARProcMod) to process the data and construct a Poyang Lake Sentinel-1 SAR dataset with a 10 m resolution. To extract water body information from Sentinel-1 SAR data, we propose an automatic classification engine based on a modified U-Net convolutional neural network (WaterUNet), which classifies all data using artificial sample datasets with a high validation accuracy. The results show that the maximum and minimum water areas in our study area were 2714.08 km2 on 20 July 2020, and 634.44 km2 on 4 January 2020. Compared to the water level data from the Poyang gauging station, the water area was highly correlated with the water level, with the correlation coefficient being up to 0.92 and the R2 from quadratic polynomial fitting up to 0.88; thus, the resulting relationship results can be used to estimate the water area or water level of Poyang Lake. According to the results, we can conclude that Sentinel-1 SAR and WaterUNet are very suitable for water body monitoring as well as emergency flood mapping.

Inland water resources are facing increasing quantitative and qualitative pressures, deriving from anthropogenic causes and the ongoing climate change. The monitoring of reservoirs is essential for sustainable management and preparation against water scarcity and extreme events, such as droughts. This research, relying on the Sentinel-2 and 3 missions, attempts to demonstrate the efficiency of combining remotely sensed water level and water area estimations, in order to estimate the water storage variation of Yliki reservoir. The case study is conducted in one of the few sufficiently monitored reservoirs in Greece, enabling a direct comparison of the proposed methodology results with in situ observations. Moreover, this research work proposes a weekly time interval for pairing level and area estimations, instead of shorter time intervals. The results strongly demonstrate the efficiency of remote sensing in the production of empirical level–area–storage (L–A–S) curves. Correlation to in situ monitored storage- and satellite-derived water level, area stand for 98.81% and 99.27% respectively. Water storage variation is estimated and compared to the observed time series, resulting in an RMSE of 1.28% of the reservoir capacity and a correlation of 96.14%. The empirical L–S relationship underestimates storage, while the A–S relationship overestimates storage when compared to the existing L–A–S curve.

With the goal of improving the real-time automatic generation of water routes and obtaining the optimal water routes, the study is based on automatic identification system (AIS) big data and electronic chart display and information system (ECDIS) water route automatic generation. The parallel AIS data processing technology of the distributed storage system is selected to realize the AIS big data processing that is automatically generated by the water route, the geodetic coordinates of the AIS information after the big data processing are transformed to Mercator projection, and the obtained Mercator coordinates are converted to the latitude and longitude of the sampling point to obtain the final sampling point. The Douglas-Peucker algorithm is selected to compress the sampling points and select the turning points from the compressed sampling points according to the fixed threshold set. The connection of the obtained turning points is the automatically generated initial water route. The ECDIS electronic chart is used to detect the generated route, and the final feasible route is the generated final water route. The experimental results show that the automatically generated water route mileage of this method is shorter, and the automatic generation time is within 300 ms, which has higher water route generation efficiency. [ABSTRACT FROM AUTHOR]

Based on the obvious anisotropy of Xisha Islands waters topography, the uneven fractal characteristics of Xisha Islands waters topography are studied by using multivariate linear expression. Using multiple linear regression analysis method to extract the projection of heterogeneous characteristic factors, the geometric heterogeneous characteristics of Xisha Islands waters are obtained. The fractal feature of landform is studied based on projection coverage method, and the non-isotropic body irregularity in Xisha Islands waters is measured. Experimental results show that this method can effectively analyze the non-uniform fractal characteristics of the Xisha Islands waters. The fractal dimension of different types of landforms in Xisha Islands in the corresponding region is high mountain area > medium and low mountain area > basin area, which reflects the difference of surface roughness or complexity of different types of landforms. The calculated fractal dimension is helpful to reveal the heterogeneity of general geomorphological features in different development stages. [ABSTRACT FROM AUTHOR]

Lake Issyk-Kul is the largest alpine lake in arid Central Asia. In recent years, the lake has become a subject of special concern due to the dramatic fluctuations in its water level. In this study, the long-term continuous changes in the water level of Lake Issyk-Kul were derived from hydro-meteorological stations, CryoSat-2, and ICESat-2 satellites. Changes in area were analyzed by the Joint Research Centre (JRC) Global Surface Water (GSW) dataset based on the Google Earth Engine and the variations in water volume were estimated by an empirical formula. The results indicate that the water level of Lake Issyk-Kul fluctuated between 1606.06 m and 1608.32 m during 1958–2020, showing a slight decrease of 0.02 m/year on average. The water level first experienced a significant decreasing trend of 0.05 m/year from 1958 to 1998, and then began to rise rapidly by 0.10 m/year during 1998–2006, followed by a fluctuating decline after 2006. The area of Lake Issyk-Kul exhibited a downward trend before 1998, then a rapid expansion during 1998–2006, and short-term fluctuations in decline thereafter. Meanwhile, changes in water volume of Lake Issyk-Kul followed a similar pattern of variations in water level and area. According to comprehensive analyses, the continuous downward trend of the water level before 1998 was primarily affected by substantial anthropogenic water consumption in the basin. However, since the 21st century, the increases in precipitation and glacier meltwater and the reduced water consumption have collectively facilitated the short-term recovery of Lake Issyk-Kul in water level, area, and water volume.

Taitema Lake, located in the lower reaches of the Tarim River and the Cherchen River, is one of the most important ecological barriers in Ruoqiang County. The amount of water in Taitema Lake plays an important role in maintaining a healthy cycle within the ecosystem, curbing sandstorms, and improving salinization and desertification. The aim of this study was to reasonably determine the volume of ecological water conveyance by calculating the ecological water demand. We systematically analyzed the spatial and temporal variation characteristics of Taitema Lake during 21 ecological water conveyance processes from 2000 to 2020. The results showed that the area of Taitema Lake increased at a rate of 144% per year because of the Ecological Water Conveyance Project (EWCP). The areas of water in dry, normal, and high flow years were 30.35, 57.76, and 103.5 km2, respectively. The corresponding ecological water demand was 1.58 × 108, 3.09 × 108, and 5.66 × 108 m3, respectively. We calculated that the Cherchen River and the Tarim River carried 0.87 × 108–3.11 × 108 m3 and 0.71 × 108–2.55 × 108 m3 of water, respectively, under different inflow frequencies. This study has significance as a reference for estimates of the ecological water demand of terminal lakes under the condition of artificial water transport in arid inland river basins, and provides the basis for the rational allocation of water resources in the Tarim River Basin.

In the present study, Landsat‐8 data have been used for water identification at the Sangam region, the confluence of the Ganges and Yamuna rivers. Since the water of both the rivers varies in characteristics, it is necessary to explore the most appropriate band of Landsat‐8 imagery for the identification of water bodies. Accordingly, a two folded study has been performed, viz., the selection of a suitable band to identify water bodies and to monitor the water level at the Sangam region from 2013 to 2018. It is observed in the study that band‐7 is the most suitable band for water identification, which is used for the classification and monitoring of water. The classification results are highly significant as the overall accuracy ranges between 95.49 and 100%. The monitoring of water level is done based on classification results for mapping the area of water in real units which can be useful for the prediction of flood situations. The achievement of the present study is the mapping of water area in real units with the help of image pixels which is one of the prominent applications of image processing in earth sciences. [ABSTRACT FROM AUTHOR]

The Miyun Reservoir is the most important source of drinking water in Beijing, China. Based on the Landsat satellite series image, this paper compared four index methods (NDWI, RNDWI, MNDWI, AWEIsh-superimposed MNDWI) to extract the water body area of Miyun Reservoir from 1979 to 2018 to study its changes in the past 40 years. Furthermore, the internal and external driving forces of reservoir water body area change are studied by correlation analysis and catastrophe analysis. Compared to the characteristic curve of reservoir area calculation, it indicated that the AWEIsh-superimposed MNDWI method has the highest accuracy. The statistical, temporal and spatial analysis showed that the water body area changes of Miyun Reservoir are mainly divided into four distinct stages: (1) It increased in 1979–1997, which was mainly due to the increase in precipitation and the low level of economic development. In 1997, the maximum value (161.14 km2) was reached, which was 108.64 km2 higher than the minimum value. (2) It shrank rapidly in 1997–2004. The areas had dropped by 101.61 km2. By 2004, it was 59.61 km2. The main reason is that the reservoir has suffered from persistent drought for many years after discharging water. (3) It maintained at a lower water level in 2004–2015, with an average annual area of 78 km2. The reason is the low precipitation and rapid economic development. (4) It grew rapidly after 2015, mainly due to water from the South-to-North Water Transfer Project, coupled with the increased precipitation. By 2018, the water body area reached 125.42 km2. [ABSTRACT FROM AUTHOR]

In the past three decades, China has built more than 87 000 dams with a storage capacity of ≈6560 km3 and the total surface area of inland water has increased by 6672 km2. Leaching of N from fertilized soils to rivers is the main source of N pollution in China, but the exposure of a growing inland water area to direct atmospheric N deposition and N leaching caused by N deposition on the terrestrial ecosystem, together with increased N deposition and decreased N flow, also tends to raise N concentrations in most inland waters. The contribution of this previously ignored source of  N deposition to freshwaters is estimated in this study, as well as mitigation strategies. The results show that the annual amounts of N depositions ranged from 4.9 to 16.6 kg · ha−1 · yr−1 in the 1990s to exceeding 20 kg · ha−1 · yr−1 in the 2010s over most of regions in China, so the total mass of ΔN (the net contribution of N deposition to the increase in N concentration) for lakes, rivers and reservoirs change from 122.26 Gg N · yr−1 in the 1990s to 237.75 Gg N · yr−1 in the 2010s. It is suggested that reducing the N deposition from various sources, shortening the water-retention time in dams and decreasing the degree of regulation for rivers are three main measures for preventing a continuous increase in the N-deposition pollution to inland water in China. [ABSTRACT FROM AUTHOR]