On the basis of on-the-spot investigation, the causes of urban black-odor water bodies and the problems existing in the treatment are analyzed, and the control techniques and management countermeasures for black-odor ...On the basis of on-the-spot investigation, the causes of urban black-odor water bodies and the problems existing in the treatment are analyzed, and the control techniques and management countermeasures for black-odor water bodies were put forward. The countermeasures include: treating from both the roots and the symptoms and combining multiple technologies; comprehensively managing and improve the monitoring systems; coordinating functions and implementing long-term management; opening information and innovating supervision platform; coordinating advance and promoting the construction of sponge city; diversified financing to form the market-oriented model of water pollution control.展开更多
At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedroc...At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedrock, and water of a typical karst watershed in southwest China were investigated. The results indicated that the average values of heavy metals in soil and sediment were relatively higher than those in bedrock except for Ni and As. During the research period, As and Cd were the main heavy metal elements polluting the soil and sediment in the study area, while water bodies were mainly polluted by Ni, As, and Cd. The pollution assessment indicated that there were instances of poor or very poor water quality in the study area during the study period;the soil as a whole was slightly polluted by Cd and As;sediment was subject to moderate Cd pollution and mild As pollution. Analysis of geochemical form for heavy metals showed that heavy metals in soil and sediment were mainly in residual form, and the proportions of exchangeable As and Cd were relatively high. Multiple statistical analysis showed that heavy metals in sediment, soil, and bedrock explained 23.8%, 16.8%, and 16.2% of the changes in heavy metals of water, respectively. The research results can provide scientific basis for the prevention and control of heavy metal pollution in water bodies.展开更多
The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to...The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to highlight water bodies in remote sensing images.We employ a new water index and digital image processing technology to extract water bodies automatically and accurately from Landsat 8 OLI images.Firstly,we preprocess Landsat 8 OLI images with radiometric calibration and atmospheric correction.Subsequently,we apply KT transformation,LBV transformation,AWEI nsh,and HIS transformation to the preprocessed image to calculate a new water index.Then,we perform linear feature enhancement and improve the local adaptive threshold segmentation method to extract small water bodies accurately.Meanwhile,we employ morphological enhancement and improve the local adaptive threshold segmentation method to extract large water bodies.Finally,we combine small and large water bodies to get complete water bodies.Compared with other traditional methods,our method has apparent advantages in water extraction,particularly in the extraction of small water bodies.展开更多
Water bodies in urban areas are important as recreational areas. Thus, management plans that maintain high water quality are quite important. At the Hatadate Water Park adjacent to Miyagi University, water quality par...Water bodies in urban areas are important as recreational areas. Thus, management plans that maintain high water quality are quite important. At the Hatadate Water Park adjacent to Miyagi University, water quality parameters such as visibility, COD, TOC, and TN were monitored at a small pond and the inflowing stream from August to December in 2011, and photographs were taken of these sites. Variations in COD and TOC were highly related to changes in the physical appearance, especially changes in vegetation. These findings suggest: 1) the importance of management of vegetation for water quality control;and 2) the importance of collecting photographic records of sites for research purposes of interpreting data and even as a data point of water quality. Together with the water quality goals for water bodies in urban areas proposed by Sudo et al. [1], these water quality criteria were assessed, and it was notable that COD often exceeded the set goal. These results suggest that the maintenance of vegetation is more important than controlling incoming TN for primary production in the pond. Seasonal variations in COD and TOC were plotted for surface water of Kamafusa and Okura dams, both are important lakes in Miyagi area and the catchments of both lakes are mainly hilly area, using published water quality reports. Similar annual-cycle changing patterns were shown both for the dams, implying that some kinds of ecological factors in the catchments are affecting the water qualities of the dam, even at those larger scale water bodies. Finally, by shifting the focus from only water to upstream features such as small park, or pocket park, with a parking lot for the water body, the importance of landscape including vegetation and tree cover was highlighted.展开更多
As a typical region with high water demand for agricultural production,understanding the spatiotemporal surface water changes in Northeast China is critical for water resources management and sustainable development.H...As a typical region with high water demand for agricultural production,understanding the spatiotemporal surface water changes in Northeast China is critical for water resources management and sustainable development.However,the long-term variation characteristics of surface water of different water body types in Northeast China remain rarely explored.This study investigated how surface water bodies of different types(e.g.,lake,reservoir,river,coastal aquaculture,marsh wetland,ephemeral water) changed during1999–2020 in Northeast China based on various remote sensing-based datasets.The results showed that surface water in Northeast China grew dramatically in the past two decades,with an equivalent area increasing from 24 394 km^(2) in 1999 to 34 595 km^(2) in 2020.The surge of ephemeral water is the primary driver of surface water expansion,which could ascribe to shifted precipitation pattern.Marsh wetlands,rivers,and reservoirs experienced a similar trend,with an approximate 20% increase at the interdecadal scale.By contrast,coastal aquacultures and natural lakes remain relatively stable.This study is expected to provide a more comprehensive investigation of the surface water variability in Northeast China and has important practical significance for the scientific management of different types of surface water.展开更多
The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were c...The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were collected from the coastal waters of Qingdao,China,and the whole body and all fins of them were red.Of the two red-colored rockfish,there were tiny deep red spots on each fin,2 red radial stripes behind and below the eyes and 1 large deep red blotch on the opercula,while the similar stripe and spot patterns are also present in the S.koreanus specimens with normal body coloration.The countable characteristics of the two specimens are in the range of the morphometry of S.koreanus.To further clarify the species identity and taxonomic status of the two specimens,DNA barcode analysis was carried out.The genetic distance between the red-colored rockfish and S.koreanus was 0,and the minimum net genetic distances between the red-colored rockfish and other Sebastes species except for S.koreanus were 3.0%,which exceeds the threshold of species delimitation.The phylogenetic analysis showed that the DNA barcoding sequences of the two red-colored rockfish clustered with the S.koreanus sequences.The above results of DNA barcode analysis also support that the two red-colored rockfish could be identified as the species of S.koreanus.The mechanism of color variation in S.koreanus is desirable for further research and the species could be an ideal model to study the color-driven speciation of the rockfishes.展开更多
Urban landscape water body is not only an important part of urban landscape construction,but also an important way to maintain landscape diversity and biodiversity,carrying the beautiful yearning of urban residents fo...Urban landscape water body is not only an important part of urban landscape construction,but also an important way to maintain landscape diversity and biodiversity,carrying the beautiful yearning of urban residents for natural life.A good state of urban landscape water body is crucial to the ecological environment of the city.However,due to the poor kinetic energy of urban landscape water body and the influence of various human factors,the quality of urban landscape water body often declines,and urban population is threatened by water security problems.Through the study of several water body ecological remediation technologies,relevant suggestions are put forward,in order to provide a reference for water pollution restoration and treatment in urban human settlement environment.展开更多
India is endowed with diverse and distinctive traditional water bodies. They support large human population and biodiversity but are under continuous stress, caused primarily by demographic pressure and unplanned grow...India is endowed with diverse and distinctive traditional water bodies. They support large human population and biodiversity but are under continuous stress, caused primarily by demographic pressure and unplanned growth. There has been a decline in their water quality and quantity and several of them have vanished, thanks to improper monitoring of these water bodies. This research study was conducted in Meerut district to help government in identifying status of traditional water bodies and suggest steps necessary for protection of these water bodies. Similar research framework, with minor customization, could be applied to any other district in India. Meerut district, with a population of around 3.5 million people is in an abysmal state as the rivers and groundwater are highly polluted. The last resort—the traditional water bodies are also getting transformed into sewage ponds. A field based research was undertaken—which involved on-ground survey using GPS, GIS mapping & water quality testing of 120 ponds, distributed across 12 blocks of Meerut district to acquire a practical understanding of the status of these water bodies. The research team also did an informal discussion with around 500 residents, located nearby ponds, to understand the water situation of the locality. Results show that more than 50% of water bodies are severely polluted (with D.O below 5mg/l) and total dissolved solids (more than 100 NTU). Fecal contamination was observed in all the ponds that were analyzed. The major problems are excessive nutrient pollution, leading to eutrophication, and sewage contamination. The spatial analysis finds out that around half the ponds have reduced in area. With around 100 upcoming cities in India and most of the cities already experiencing water scarcity, it is essential to digitize, monitor, control & prevent pollution and most essentially make the people and grassroots institutions aware in order to protect these essential water bodies from getting extinct.展开更多
The order Diptera(Insecta)is one of animal groups most successful in the colonization of mineralized shallow aquatic and semiaquatic environments.At the same time,the taxonomic composition of Diptera,their role
One of the main environmental issues at present times is the pollution of hydrological resources. Water quality is a major factor to ecosystems, mostly those that support human health, food production and biodiversity...One of the main environmental issues at present times is the pollution of hydrological resources. Water quality is a major factor to ecosystems, mostly those that support human health, food production and biodiversity. The utilization of renewable energy sources as solar energy through Photovoltaic Cells is a competitive and consolidated option to approach the solution of this kind of issues. This document is intended to introduce a prototype powered by photovoltaic cells to aerate a body of water and increase the amount of Dissolved Oxygen (DO) in water. The body of water studied is the lagoon Laguna del Carpintero in Tampico, Tamaulipas, Mexico. A Stand-alone Photovoltaic System (SPS) prototype was designed for this matter with the purpose of powering a pumping system to sprinkle water to the lake’s surface. This system is a way of ventilating the water so that it gets in direct contact with the surrounding atmosphere obtaining mean values compared to prevailing values of DO contained in the lagoon. We obtained DO concentration values going from 7 to 8 mg/L of O2 in different tests which can be considered an appropriate parameter for this body of water. The efficiency of the SPS was proved as it showed good performance by supplying power to the oxygenation system compared to the dimensional estimate. Improving the SPS prototype is the main goal of this work so that this oxygenation system could be used in other urban lagoons in the surrounding area without being powered by electrical grid. This makes possible to locate it at any point of the body of water to mitigate the pollution by increasing the amount of DO.展开更多
Human actions rather than natural forces are the source of most contemporary changes in the state and flows of the biosphere. Understanding these actions and the social forces that drive them is crucial to understandi...Human actions rather than natural forces are the source of most contemporary changes in the state and flows of the biosphere. Understanding these actions and the social forces that drive them is crucial to understanding, modelling and predicting local, regional as well as global environmental change and also for managing and responding to such change. The present study investigates the patterns of urban land transformation in Srinagar City, which lies in fragile hill eco-system of Kashmir valley. The results points towards unplanned and haphazard urban expansion and transformation. These transformations have severely destroyed the water bodies both in terms of area as well as its quality.展开更多
Bacterial attachment is influenced by the cell surface, attachment media and other environmental factors. Bacterial community composition involved in biofilm formation in extremely high rainfall areas like Cherrapunje...Bacterial attachment is influenced by the cell surface, attachment media and other environmental factors. Bacterial community composition involved in biofilm formation in extremely high rainfall areas like Cherrapunjee has not been reported. The present study was undertaken to characterize bacteria involved in biofilm formation on different substrata in water bodies of Cherrapunjee, the highest rainfall receiving place on planet earth and to assess if the continuous rainfall has an effect on nature and colonization of biofilm bacteria. We developed the biofilm bacteria on stainless steel and glass surfaces immersed in water bodies of the study sites. Isolation of biofilm bacteria were performed on different culture media followed by estimation of protein and carbohydrate content of bacterial exopolysaccharides. 16S rRNA gene sequences were amplified for molecular characterization. The results showed that the biofilm bacterial diversity in water bodies of Cherrapunjee was influenced by substratum and was observed more in stainless steel than glass surface. Scanning electron microscopy images revealed that biofilm microstructure may represent a key determinant of biofilm growth and physiology of associated bacteria. The overall protein content of the extracted EPS of all the isolates were relatively higher than the carbohydrate content. Diverse bacteria proliferated on the substrata regardless of each other's presence, with more diverse bacteria colonizing the substrata on 7th day compared to 15th day of incubation. The biofilm bacteria compositions in the highest rainfall receiving habitat were not distinctly different from reports available, hence not unique from other water bodies.展开更多
Engineering nano-materials & their impact on human health or environmental security constitute a newly emerging R&D hot spot and a key problem now urgently waiting for its solution in supporting the sustainabi...Engineering nano-materials & their impact on human health or environmental security constitute a newly emerging R&D hot spot and a key problem now urgently waiting for its solution in supporting the sustainability of China's nano-science and related technology development. At present, water bodies in Chinese cities have been seriously polluted by metallic nano-particles (MNPs) while related monitoring data are found woefully lacking throughout the country. Based on the above understanding, this article gives a round-up explanation on distributive characteristics of MNPs in the river mouths or water bodies of Chinese cities, their ecological hazards as well as our research in this regard, providing some inspiring ideas and data for control over this scourge. In addition, our exploration probes the discharge traits of MNPs themselves and the mechanism underlying its impact on water pollution.展开更多
The present paper focuses on the wave radiation by an oscillating body with six degrees of freedom by using the DtN artifi-cial boundary condition.The artificial boundary is usually selected as a circle or spherical s...The present paper focuses on the wave radiation by an oscillating body with six degrees of freedom by using the DtN artifi-cial boundary condition.The artificial boundary is usually selected as a circle or spherical surface to solve various types of fields,such as sound waves or electromagnetic waves,provided that the considered domain is infinite or unbounded in all directions.However,the substantial wave motion is considered in water of finite depth,that is,the fluid domain is bounded vertically but unbounded horizon-tally.Thus,the DtN boundary condition is given on an artificial cylindrical surface,which divides the water domain into an interior and exterior region.The boundary integral equation is adopted to implement the present model.In the case of a floating cylinder,the results of hydrodynamic coefficients of a chamfer box are discussed.展开更多
There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources ...There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources in sur-rounding areas and downstream areas,resulting in environmental impact and bringing potential flood disasters,which will induce more serious issues and problems in alpine and high-altitude areas with a fragile habitat(such as the QTP in China).Generally,effective,reasonable,and scientific monitoring of large-scale water bodies can not only document the changes in water bodies intuitively,but also provide important theoretical reference for subsequent environmental impact prediction,and disaster prevention and mitigation in due course of time.The large-scale water extraction technology derived from the optical remote sensing(RS)image is seriously affected by clouds,bringing about large differences among the extracted water result products.Synthetic aperture radar(SAR)RS technology has the unique advantage characteristics of all-weather,all-day,strong penetration,and not being affected by clouds,which is hopeful in extracting water body data,especially for days with cloudy weather.The data extraction of large-scale water bodies based on SAR images can effectively avoid the errors caused by clouds that become prevalent at present.In this paper,the Hoh Xil Salt Lake on the QTP and its surrounding five lakes are taken as the research objects.The 2-scene Sentinel-1 SAR image data covering the whole area on 22 August 2022 was used to verify the feasibility of extracting water body data in permafrost zones.Furthermore,on 22 August 2022,the wealth here was cloudy,which made the optical RS images,e.g.,Sentinel-2 images full of clouds.The results show that:using the Sentinel-1 image and threshold segmentation method to extract water body data is efficient and effective with excellent results in permafrost areas.Concretely,the Sentinel-1 dual-polarized water index(SDWI),calculated by combining dual vertical–vertical(VV)polarized and verti-cal–horizontal(VH)polarized data is a useful index for water extraction and the result is better than each of the VV or VH polarized images.展开更多
基金supported by Jiangsu Qinglan Project of 2016Research Project of Jiangsu Provincial Party Committee titled "China democratic league: Regulation of malodorous black river and improvement of waterfront environment in city"Key Funding Project of Jiangsu Polytechnic College of Agriculture and Forestry (Grant No. 2016kj005)
文摘On the basis of on-the-spot investigation, the causes of urban black-odor water bodies and the problems existing in the treatment are analyzed, and the control techniques and management countermeasures for black-odor water bodies were put forward. The countermeasures include: treating from both the roots and the symptoms and combining multiple technologies; comprehensively managing and improve the monitoring systems; coordinating functions and implementing long-term management; opening information and innovating supervision platform; coordinating advance and promoting the construction of sponge city; diversified financing to form the market-oriented model of water pollution control.
基金Guizhou Provincial Key Technology R&D Program (2202023QKHZC).
文摘At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedrock, and water of a typical karst watershed in southwest China were investigated. The results indicated that the average values of heavy metals in soil and sediment were relatively higher than those in bedrock except for Ni and As. During the research period, As and Cd were the main heavy metal elements polluting the soil and sediment in the study area, while water bodies were mainly polluted by Ni, As, and Cd. The pollution assessment indicated that there were instances of poor or very poor water quality in the study area during the study period;the soil as a whole was slightly polluted by Cd and As;sediment was subject to moderate Cd pollution and mild As pollution. Analysis of geochemical form for heavy metals showed that heavy metals in soil and sediment were mainly in residual form, and the proportions of exchangeable As and Cd were relatively high. Multiple statistical analysis showed that heavy metals in sediment, soil, and bedrock explained 23.8%, 16.8%, and 16.2% of the changes in heavy metals of water, respectively. The research results can provide scientific basis for the prevention and control of heavy metal pollution in water bodies.
基金Auhui Provincial Key Research and Development Project(No.202004a07020050)National Natural Science Foundation of China Youth Program(No.61901006)。
文摘The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to highlight water bodies in remote sensing images.We employ a new water index and digital image processing technology to extract water bodies automatically and accurately from Landsat 8 OLI images.Firstly,we preprocess Landsat 8 OLI images with radiometric calibration and atmospheric correction.Subsequently,we apply KT transformation,LBV transformation,AWEI nsh,and HIS transformation to the preprocessed image to calculate a new water index.Then,we perform linear feature enhancement and improve the local adaptive threshold segmentation method to extract small water bodies accurately.Meanwhile,we employ morphological enhancement and improve the local adaptive threshold segmentation method to extract large water bodies.Finally,we combine small and large water bodies to get complete water bodies.Compared with other traditional methods,our method has apparent advantages in water extraction,particularly in the extraction of small water bodies.
文摘Water bodies in urban areas are important as recreational areas. Thus, management plans that maintain high water quality are quite important. At the Hatadate Water Park adjacent to Miyagi University, water quality parameters such as visibility, COD, TOC, and TN were monitored at a small pond and the inflowing stream from August to December in 2011, and photographs were taken of these sites. Variations in COD and TOC were highly related to changes in the physical appearance, especially changes in vegetation. These findings suggest: 1) the importance of management of vegetation for water quality control;and 2) the importance of collecting photographic records of sites for research purposes of interpreting data and even as a data point of water quality. Together with the water quality goals for water bodies in urban areas proposed by Sudo et al. [1], these water quality criteria were assessed, and it was notable that COD often exceeded the set goal. These results suggest that the maintenance of vegetation is more important than controlling incoming TN for primary production in the pond. Seasonal variations in COD and TOC were plotted for surface water of Kamafusa and Okura dams, both are important lakes in Miyagi area and the catchments of both lakes are mainly hilly area, using published water quality reports. Similar annual-cycle changing patterns were shown both for the dams, implying that some kinds of ecological factors in the catchments are affecting the water qualities of the dam, even at those larger scale water bodies. Finally, by shifting the focus from only water to upstream features such as small park, or pocket park, with a parking lot for the water body, the importance of landscape including vegetation and tree cover was highlighted.
基金Under the auspices of Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA28020503,XDA23100102)National Key Research and Development Program of China(No.2019YFA0607101)+1 种基金Project of China Geological Survey(No.DD20230505)Excellent Scientific Research and Innovation Team of Universities in Anhui Province(No.2023AH010071)。
文摘As a typical region with high water demand for agricultural production,understanding the spatiotemporal surface water changes in Northeast China is critical for water resources management and sustainable development.However,the long-term variation characteristics of surface water of different water body types in Northeast China remain rarely explored.This study investigated how surface water bodies of different types(e.g.,lake,reservoir,river,coastal aquaculture,marsh wetland,ephemeral water) changed during1999–2020 in Northeast China based on various remote sensing-based datasets.The results showed that surface water in Northeast China grew dramatically in the past two decades,with an equivalent area increasing from 24 394 km^(2) in 1999 to 34 595 km^(2) in 2020.The surge of ephemeral water is the primary driver of surface water expansion,which could ascribe to shifted precipitation pattern.Marsh wetlands,rivers,and reservoirs experienced a similar trend,with an approximate 20% increase at the interdecadal scale.By contrast,coastal aquacultures and natural lakes remain relatively stable.This study is expected to provide a more comprehensive investigation of the surface water variability in Northeast China and has important practical significance for the scientific management of different types of surface water.
基金Supported by the National Key R&D Program of China (No.2018YFD0900803)the China Agriculture Research System of MOF and MARA (No.CARS-47)the Central Public-Interest Scientific Institution Basal Research Fund (Nos.2021JC01,20603022022024)
文摘The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were collected from the coastal waters of Qingdao,China,and the whole body and all fins of them were red.Of the two red-colored rockfish,there were tiny deep red spots on each fin,2 red radial stripes behind and below the eyes and 1 large deep red blotch on the opercula,while the similar stripe and spot patterns are also present in the S.koreanus specimens with normal body coloration.The countable characteristics of the two specimens are in the range of the morphometry of S.koreanus.To further clarify the species identity and taxonomic status of the two specimens,DNA barcode analysis was carried out.The genetic distance between the red-colored rockfish and S.koreanus was 0,and the minimum net genetic distances between the red-colored rockfish and other Sebastes species except for S.koreanus were 3.0%,which exceeds the threshold of species delimitation.The phylogenetic analysis showed that the DNA barcoding sequences of the two red-colored rockfish clustered with the S.koreanus sequences.The above results of DNA barcode analysis also support that the two red-colored rockfish could be identified as the species of S.koreanus.The mechanism of color variation in S.koreanus is desirable for further research and the species could be an ideal model to study the color-driven speciation of the rockfishes.
文摘Urban landscape water body is not only an important part of urban landscape construction,but also an important way to maintain landscape diversity and biodiversity,carrying the beautiful yearning of urban residents for natural life.A good state of urban landscape water body is crucial to the ecological environment of the city.However,due to the poor kinetic energy of urban landscape water body and the influence of various human factors,the quality of urban landscape water body often declines,and urban population is threatened by water security problems.Through the study of several water body ecological remediation technologies,relevant suggestions are put forward,in order to provide a reference for water pollution restoration and treatment in urban human settlement environment.
文摘India is endowed with diverse and distinctive traditional water bodies. They support large human population and biodiversity but are under continuous stress, caused primarily by demographic pressure and unplanned growth. There has been a decline in their water quality and quantity and several of them have vanished, thanks to improper monitoring of these water bodies. This research study was conducted in Meerut district to help government in identifying status of traditional water bodies and suggest steps necessary for protection of these water bodies. Similar research framework, with minor customization, could be applied to any other district in India. Meerut district, with a population of around 3.5 million people is in an abysmal state as the rivers and groundwater are highly polluted. The last resort—the traditional water bodies are also getting transformed into sewage ponds. A field based research was undertaken—which involved on-ground survey using GPS, GIS mapping & water quality testing of 120 ponds, distributed across 12 blocks of Meerut district to acquire a practical understanding of the status of these water bodies. The research team also did an informal discussion with around 500 residents, located nearby ponds, to understand the water situation of the locality. Results show that more than 50% of water bodies are severely polluted (with D.O below 5mg/l) and total dissolved solids (more than 100 NTU). Fecal contamination was observed in all the ponds that were analyzed. The major problems are excessive nutrient pollution, leading to eutrophication, and sewage contamination. The spatial analysis finds out that around half the ponds have reduced in area. With around 100 upcoming cities in India and most of the cities already experiencing water scarcity, it is essential to digitize, monitor, control & prevent pollution and most essentially make the people and grassroots institutions aware in order to protect these essential water bodies from getting extinct.
基金supported by the Russian Foundation for Basic Research (grant no. 14-04-01139)supported by a travel grant from the Organizing Committee
文摘The order Diptera(Insecta)is one of animal groups most successful in the colonization of mineralized shallow aquatic and semiaquatic environments.At the same time,the taxonomic composition of Diptera,their role
文摘One of the main environmental issues at present times is the pollution of hydrological resources. Water quality is a major factor to ecosystems, mostly those that support human health, food production and biodiversity. The utilization of renewable energy sources as solar energy through Photovoltaic Cells is a competitive and consolidated option to approach the solution of this kind of issues. This document is intended to introduce a prototype powered by photovoltaic cells to aerate a body of water and increase the amount of Dissolved Oxygen (DO) in water. The body of water studied is the lagoon Laguna del Carpintero in Tampico, Tamaulipas, Mexico. A Stand-alone Photovoltaic System (SPS) prototype was designed for this matter with the purpose of powering a pumping system to sprinkle water to the lake’s surface. This system is a way of ventilating the water so that it gets in direct contact with the surrounding atmosphere obtaining mean values compared to prevailing values of DO contained in the lagoon. We obtained DO concentration values going from 7 to 8 mg/L of O2 in different tests which can be considered an appropriate parameter for this body of water. The efficiency of the SPS was proved as it showed good performance by supplying power to the oxygenation system compared to the dimensional estimate. Improving the SPS prototype is the main goal of this work so that this oxygenation system could be used in other urban lagoons in the surrounding area without being powered by electrical grid. This makes possible to locate it at any point of the body of water to mitigate the pollution by increasing the amount of DO.
文摘Human actions rather than natural forces are the source of most contemporary changes in the state and flows of the biosphere. Understanding these actions and the social forces that drive them is crucial to understanding, modelling and predicting local, regional as well as global environmental change and also for managing and responding to such change. The present study investigates the patterns of urban land transformation in Srinagar City, which lies in fragile hill eco-system of Kashmir valley. The results points towards unplanned and haphazard urban expansion and transformation. These transformations have severely destroyed the water bodies both in terms of area as well as its quality.
文摘Bacterial attachment is influenced by the cell surface, attachment media and other environmental factors. Bacterial community composition involved in biofilm formation in extremely high rainfall areas like Cherrapunjee has not been reported. The present study was undertaken to characterize bacteria involved in biofilm formation on different substrata in water bodies of Cherrapunjee, the highest rainfall receiving place on planet earth and to assess if the continuous rainfall has an effect on nature and colonization of biofilm bacteria. We developed the biofilm bacteria on stainless steel and glass surfaces immersed in water bodies of the study sites. Isolation of biofilm bacteria were performed on different culture media followed by estimation of protein and carbohydrate content of bacterial exopolysaccharides. 16S rRNA gene sequences were amplified for molecular characterization. The results showed that the biofilm bacterial diversity in water bodies of Cherrapunjee was influenced by substratum and was observed more in stainless steel than glass surface. Scanning electron microscopy images revealed that biofilm microstructure may represent a key determinant of biofilm growth and physiology of associated bacteria. The overall protein content of the extracted EPS of all the isolates were relatively higher than the carbohydrate content. Diverse bacteria proliferated on the substrata regardless of each other's presence, with more diverse bacteria colonizing the substrata on 7th day compared to 15th day of incubation. The biofilm bacteria compositions in the highest rainfall receiving habitat were not distinctly different from reports available, hence not unique from other water bodies.
文摘Engineering nano-materials & their impact on human health or environmental security constitute a newly emerging R&D hot spot and a key problem now urgently waiting for its solution in supporting the sustainability of China's nano-science and related technology development. At present, water bodies in Chinese cities have been seriously polluted by metallic nano-particles (MNPs) while related monitoring data are found woefully lacking throughout the country. Based on the above understanding, this article gives a round-up explanation on distributive characteristics of MNPs in the river mouths or water bodies of Chinese cities, their ecological hazards as well as our research in this regard, providing some inspiring ideas and data for control over this scourge. In addition, our exploration probes the discharge traits of MNPs themselves and the mechanism underlying its impact on water pollution.
文摘The present paper focuses on the wave radiation by an oscillating body with six degrees of freedom by using the DtN artifi-cial boundary condition.The artificial boundary is usually selected as a circle or spherical surface to solve various types of fields,such as sound waves or electromagnetic waves,provided that the considered domain is infinite or unbounded in all directions.However,the substantial wave motion is considered in water of finite depth,that is,the fluid domain is bounded vertically but unbounded horizon-tally.Thus,the DtN boundary condition is given on an artificial cylindrical surface,which divides the water domain into an interior and exterior region.The boundary integral equation is adopted to implement the present model.In the case of a floating cylinder,the results of hydrodynamic coefficients of a chamfer box are discussed.
基金funded by the Second Tibetan Plateau Scientific Expedition and Research(STEP)program,grant number 2019QZKK0905the National Natural Science Foundation of China,grant number 42272339,42201162,42101121the Research Project of the State Key Laboratory of Frozen Soils Engineering,grant number SKLFSE-ZQ-58,SKLFSE-ZT-202203,SKLFSE-ZY-20.
文摘There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources in sur-rounding areas and downstream areas,resulting in environmental impact and bringing potential flood disasters,which will induce more serious issues and problems in alpine and high-altitude areas with a fragile habitat(such as the QTP in China).Generally,effective,reasonable,and scientific monitoring of large-scale water bodies can not only document the changes in water bodies intuitively,but also provide important theoretical reference for subsequent environmental impact prediction,and disaster prevention and mitigation in due course of time.The large-scale water extraction technology derived from the optical remote sensing(RS)image is seriously affected by clouds,bringing about large differences among the extracted water result products.Synthetic aperture radar(SAR)RS technology has the unique advantage characteristics of all-weather,all-day,strong penetration,and not being affected by clouds,which is hopeful in extracting water body data,especially for days with cloudy weather.The data extraction of large-scale water bodies based on SAR images can effectively avoid the errors caused by clouds that become prevalent at present.In this paper,the Hoh Xil Salt Lake on the QTP and its surrounding five lakes are taken as the research objects.The 2-scene Sentinel-1 SAR image data covering the whole area on 22 August 2022 was used to verify the feasibility of extracting water body data in permafrost zones.Furthermore,on 22 August 2022,the wealth here was cloudy,which made the optical RS images,e.g.,Sentinel-2 images full of clouds.The results show that:using the Sentinel-1 image and threshold segmentation method to extract water body data is efficient and effective with excellent results in permafrost areas.Concretely,the Sentinel-1 dual-polarized water index(SDWI),calculated by combining dual vertical–vertical(VV)polarized and verti-cal–horizontal(VH)polarized data is a useful index for water extraction and the result is better than each of the VV or VH polarized images.
