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First record of abnormal body coloration in a rockfish Sebastes koreanus(Scorpaenoidei:Sebastidae)from coastal water of China based on morphological characteristics and DNA barcoding
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作者 Ang LI Huan WANG +1 位作者 Changting AN Shufang LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期640-646,共7页
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
关键词 abnormal body coloration Sebastes koreanus coastal water of China Yellow Sea morphological characteristics DNA barcoding
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Ecological Remediation Technology of Urban Landscape Water Body
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作者 SUN Xiangxuan XIONG Qingqing XIAO Shizhen 《Journal of Landscape Research》 2024年第1期55-58,共4页
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
关键词 Urban landscape water body water body treatment Ecological remediation
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Quantitative Evaluation of Heavy Metal Pollution and Its Influencing Factors in Water Bodies of Karst Areas
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作者 Dijin MU Shizhen XIAO 《Meteorological and Environmental Research》 2024年第1期75-82,共8页
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
关键词 water body SEDIMENT Soil BEDROCK Speciation forms POLLUTION Influence factor
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Automated Extraction for Water Bodies Using New Water Index from Landsat 8 OLI Images 被引量:1
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作者 Pu YAN Yue FANG +2 位作者 Jie CHEN Gang WANG Qingwei TANG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期59-75,共17页
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
关键词 water bodies extraction Landsat 8 OLI images water index improved local adaptive threshold segmentation linear feature enhancement
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Wave Radiation by a Floating Body in Water of Finite Depth Using an Exact DtN Boundary Condition
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作者 RIM Un-Ryong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第6期1497-1504,共8页
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
关键词 wave radiation boundary element method Dirichlet-to-Neumann map artificial boundary floating body finite-depth water
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Extracting water body data based on SDWI and threshold segmentation:A case study in permafrost area surrounding Salt Lake in Hoh Xil,Qinghai-Tibet Plateau,China
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作者 QingSong Du GuoYu Li +4 位作者 Dun Chen ShunShun Qi Yu Zhou Fei Wang YaPeng Cao 《Research in Cold and Arid Regions》 CSCD 2023年第4期202-209,共8页
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
关键词 Permafrost region water body extraction Salt Lake in Hoh Xil Qinghai-Tibet Plateau Sentinel-1 Ecological environment impact Disaster prevention and mitigation
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Monitoring Surface Water Change in Northeast China in 1999–2020:Evidence from Satellite Observation and Refined Classification
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作者 LIU Kai ZHANG Dapeng +3 位作者 CHEN Tan CUI Peipei FAN Chenyu SONG Chunqiao 《Chinese Geographical Science》 SCIE CSCD 2024年第1期106-117,共12页
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
关键词 surface water spatiotemporal variation water body classification remote sensing Northeast China
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Fractionation mechanism of stable isotope in evaporating water body 被引量:7
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作者 ZHANG Xinping TIAN Lide LIU Jingmiao 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期375-384,共10页
Under Rayleigh equilibrium condition, stable isotopic ratio in residual water increases with the decrease of the residual water proportion f exponentially, and the fractionation rate of stable isotopes is inversely pr... Under Rayleigh equilibrium condition, stable isotopic ratio in residual water increases with the decrease of the residual water proportion f exponentially, and the fractionation rate of stable isotopes is inversely proportional to temperature. However, under kinetic evaporation condition, the fi'actionation of stable isotopes is not only related to the phase temperature but also influenced by the atmospheric humidity and the mass exchange between liquid and vapor phases. The ratio 6 in residual water will not change with f after undergoing evaporation of a long time for great relative humidity. The rate that the evaporating water body reaches isotopic steady state is mainly dependent on the relative humidity in atmosphere. The analysis shows that the actual mean linear variety rates, about -30.0, of the δ^18O in residual water versus the residual water proportion at Nagqu and Amdo stations are consistent with the simulated process under temperature of 20℃ and relative humidity of 50%. The distillation line simulated under Rayleigh equilibrium condition is analogous to the global meteoric water line (MWL) as the temperature is about 20℃. Under non-equilibrium condition, the slope and constant values of distillation line are directly proportional to temperature and relative humidity. According to the basic data, the simulated distillation line is very consistent with the actual distillation line of Qinghai Lake. 展开更多
关键词 stable isotope EVAPORATION kinetic fractionation distillation line water body
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Landscape pattern dynamics of water body in Kaifeng city in the 20th century 被引量:5
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作者 CAOXinxiang DINGShengyan 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期106-114,共9页
Landscape spatial pattern mainly refers to the distribution of patches, which are different in size and shape in space owing to the interaction of various ecological activities. In landscape ecology study, landscape p... Landscape spatial pattern mainly refers to the distribution of patches, which are different in size and shape in space owing to the interaction of various ecological activities. In landscape ecology study, landscape pattern has been one of the key study areas. Water body landscape plays an important role in the development history of a city, but at present city water body landscape in many cities has been destroyed, hence protecting water body in the city is becoming more and more important. In order to protect city water body landscape reasonably, the precondition is to probe the dynamics of water body landscape. Based on historical data and remote sensing data, six indexes including patch number, patch area, landscape dominance index, fractal dimension, patch density and connectivity index etc. were used to analyze landscape pattern dynamics of water body in Kaifeng city since the end of the Qing Dynasty (in the 20th century). The results showed: (1) Since the end of the Qing Dynasty, landscape area of water body in Kaifeng city increased first and then decreased from 1898 to 2002AD; the landscape dominant degree had the same changing tendency with the area. (2) Patch number of water body landscape in Kaifeng city had an increase from 1898 to 2002, but maximum area of patch, minimum area of patch and average area of patch decreased, which resulted in an increase in landscape fragment degree. (3) Connectivity index decreased and fractal dimension increased from 1898 to 2002. The reasons for these changes were the repeated overflows and flooding of the Yellow River and the influence of human activities. 展开更多
关键词 landscape pattern water body DYNAMICS Kaifeng city the early 20th century
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Mechanism of combination membrane and electro-winning process on treatment and remediation of Cu^(2+) polluted water body 被引量:3
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作者 ZHANG Linnan WU Yanjun +2 位作者 QU Xiaoyan LI Zhenshan NI Jinren 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第6期764-769,共6页
Mechanism of treatment and remediation of synthetic Cu^2+ polluted water body by membrane and electro-winning combination process was investigated.The influences of electrolysis voltage,pH,and electrolysis time on th... Mechanism of treatment and remediation of synthetic Cu^2+ polluted water body by membrane and electro-winning combination process was investigated.The influences of electrolysis voltage,pH,and electrolysis time on the metal recovery effciencies were studied.Relationship between trans-membrane pressure drop(△P),additions ratio,initial Cu^2+ concentration on operating effciency,stability of membrane and the possibility of water reuse were also investigated.The morphology of membrane and electrodes were observed using scanning electron microscopy(SEM),the composition of surface deposits was ascertained using combined energy dispersive X-ray spectroscopy(EDX) and atomic absorption spectrophotometer.The results showed that using low pressure reverse osmosis(LPRO),Cu^2+ concentration could increase from 20 to 100 mg/L or even higher in concentrated solutions and permeate water conductivity could be less than 20 μS/cm.The addition of sodium dodecy/sulfate sodium dodecyl sulfate improved Cu^2+ removal effciency,while EDTA had little side influence.In electro-reduction process,using plante electrode cell,Cu^2+ concentration could be further reduced to 5 mg/L,and the average current effciency ranged from 9% to 40%.Using 3D electrolysis treatment,Cu^2+ concentration could be reduced to 0.5 mg/L with a current effciency range 60%-70%. 展开更多
关键词 heavy metal water body membranes electro-winning REMEDIATION
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Performances of conventional fusion methods evaluated for inland water body observation using GF-1 image 被引量:3
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作者 Yong Du Xiaoyu Zhang +1 位作者 Zhihua Mao Jianyu Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第1期172-179,共8页
Satellite remote sensing of inland water body requires a high spatial resolution and a multiband narrow spectral resolution, which makes the fusion between panchromatic(PAN) and multi-spectral(MS) images particularly ... Satellite remote sensing of inland water body requires a high spatial resolution and a multiband narrow spectral resolution, which makes the fusion between panchromatic(PAN) and multi-spectral(MS) images particularly important. Taking the Daquekou section of the Qiantang River as an observation target, four conventional fusion methods widely accepted in satellite image processing, including pan sharpening(PS), principal component analysis(PCA), Gram-Schmidt(GS), and wavelet fusion(WF), are utilized to fuse MS and PAN images of GF-1.The results of subjective and objective evaluation methods application indicate that GS performs the best,followed by the PCA, the WF and the PS in the order of descending. The existence of a large area of the water body is a dominant factor impacting the fusion performance. Meanwhile, the ability of retaining spatial and spectral informations is an important factor affecting the fusion performance of different fusion methods. The fundamental difference of reflectivity information acquisition between water and land is the reason for the failure of conventional fusion methods for land observation such as the PS to be used in the presence of the large water body. It is suggested that the adoption of the conventional fusion methods in the observing water body as the main target should be taken with caution. The performances of the fusion methods need re-assessment when the large-scale water body is present in the remote sensing image or when the research aims for the water body observation. 展开更多
关键词 GF-1 satellite IMAGE FUSION methods FUSION evaluation INLAND water body
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Water Quality Criteria for Water Bodies in Urban Areas and Accompanying Changes in Surrounding and <i>In-Situ</i>Vegetation: Considerations from the Landscape Aspect of Planning Water Recreational Areas 被引量:1
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作者 Shigeki Harada Risa Wagatsuma +2 位作者 Tatsunari Koseki Toshiaki Aoki Taisuke Hashimoto 《Journal of Water Resource and Protection》 2013年第2期156-163,共8页
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
关键词 Small water body COD TOC VEGETATION LANDSCAPE
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Pollution control of urban black-odor water bodies 被引量:4
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作者 FAN Kai-qing JIA Jun +1 位作者 SUN Ping-li LIANG Hui-min 《Ecological Economy》 2017年第4期344-350,共7页
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
关键词 black-odor water bodies pollution control control techniques
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Strategy &Techniques for Restoration of Healthy Aquaecosystem from Toxic Super Eutrophic Water Body 被引量:1
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作者 Peimin Pu Jiangping Pu 《Journal of Geoscience and Environment Protection》 2015年第6期55-61,共7页
There are complex river-lake systems in the Taihu Lake catchment with total water surface area of 6174.7 km2, and population density of 1079/km2, including Taihu Lake water surface area of 2338 km2. The water systems ... There are complex river-lake systems in the Taihu Lake catchment with total water surface area of 6174.7 km2, and population density of 1079/km2, including Taihu Lake water surface area of 2338 km2. The water systems in this catchment have healthy aquaecosystems during long history. However, in some riverlets in this catchment the water quality was estimated as “acute toxicity for higher organisms” and over standards for many heavy metal elements content;there were no any living plants and macro organisms in the water body, because there were developed a series of industry with abundant release of heavy metals and difficult decomposition organic chemical components along the riverlets during last decades. The even more serious situation was observed in sediments of the riverlets. How to restore such riverlet into a healthy aquaeosystem with abound plants and higher organisms? The main strategy and techniques are described in this paper as summarizing a report of engineering in a riverlet in Wuxi New District during last years, which leads to restore the aquaecosystem into a healthy one with abundant surface plant cultured on floating islands and observed living fish, lobster, frog, toad, mollusk and others in the riverlet. The main techniques are: 1) softwall buffer technic;2) floating eco-island technic by using which can culture any plant which can be cultured in solution;3) immobilized nitrogen cycle bacteria (INCB) technic;4) tattering esters and other big-molecule organic chemicals by using electronic pulse technic and photosensitization technic;5) mist spray facility technic for improving dissolved oxygen in deep water layers;6) technic for buffering and suppressing H2S release from water;7) the appropriate portion of surface with cultured plant to the total water surface area is about 1/3;8) Cress [Oenanthe Ljavanica (Bl.) DC.] and Myriophyllum verticilatum L. may be cultured in Taihu Lake catchment during the whole year as main plants with mosaic combination of other supplement plants in different seasons. 展开更多
关键词 RESTORATION of HEALTHY Aquaecosystem TOXIC water body Electronic Pulse Technique for DECOMPOSITION Esters PHOTOSENSITIZATION for DECOMPOSITION of Organic Matters Floating Eco-Islands Immobilized Nitrogen Cycle Bacteria
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Effects of water depth and substrate color on the growth and body color of the red sea cucumber,Apostichopus japonicus 被引量:3
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作者 姜森颢 董双林 +2 位作者 高勤峰 任贻超 王芳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期616-623,共8页
Three color variants of the sea cucumber,Apostichopus japonicus are recognized,the red one is highly valued in the market. When the red variant is cultured in ponds in China,its body color changes from red to celadon ... Three color variants of the sea cucumber,Apostichopus japonicus are recognized,the red one is highly valued in the market. When the red variant is cultured in ponds in China,its body color changes from red to celadon in 3–6 months. The effects of water depth and substrate color on the growth and body color of this animal were investigated. Juveniles of red A. japonicus were cultured in cages suspended at a range of water depths(20,50,100,150 and 200 cm). The specific growth rate of red sea cucumbers was significantly higher in animals cultured at deeper water layers compared with those grown at shallowers. Body weights were greatest for sea cucumbers cultured at a depth of 150 cm and their survival rates were highest at a depth of 200 cm. A scale to evaluate the color of red sea cucumbers(R value) was developed using a Pantone standard color card. All stocked animals in the 9-month trial retained a red color,however the red body color was much more intense in sea cucumbers cultured at shallower depths,while animals suspended in deeper layers became pale. In a separate trial,A. japonicus were cultured in suspended cages with seven different colored substrates. Substrate color had a significant effect on the growth and body-color of red A. japonicus. The yield were greatest for A. japonicus cultured on a yellow substrate,followed by green > white > orange > red > black and blue. All sea cucumbers in the 7-month trial retained a red color,although the red was most intense(highest R value) in animals cultured on a blue substrate and pale(lowest R value) for animals cultured on a green substrate. 展开更多
关键词 车身颜色 海参 水深 色彩效果 底物 特定生长率 身体 体色变化
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Development of a Model for Water and Heat Exchange Between the Atmosphere and a Water Body
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作者 孙菽芬 颜金凤 +1 位作者 夏南 孙长海 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第5期927-938,共12页
A model for studying the heat and mass exchange between the atmosphere and a water body is developed, in which the phase change process of water freezing in winter and melting in summer and the function of the convect... A model for studying the heat and mass exchange between the atmosphere and a water body is developed, in which the phase change process of water freezing in winter and melting in summer and the function of the convective mixing process are taken into consideration. The model uses enthalpy rather than temperature as the predictive variable. It helps to set up governing equations more concisely, to deal with the phase change process more easily, and make the numerical scheme simpler. The model is verified by observed data from Lake Kinneret for a non-frozen lake in summer time, and Lake Lower Two Medicine for a frozen lake in winter time. Reasonably good agreements between the model simulations and observed data indicate that the model can serve as a component for a water body in a land surface model. In order to more efficiently apply the scheme in a climate system model, a sensitivity study of various division schemes with less layers in the vertical direction in the water body is conducted. The results of the study show that the division with around 10 vertical layers could produce a prediction accuracy that is comparable to the fine division with around 40 layers. 展开更多
关键词 water body model ENTHALPY convective mixing model validation
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Dying Traditional Water Bodies in India Struggling to Survive against Unplanned Development
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作者 Rudresh Sugam Bhawna Gupta Diticha Deka 《Journal of Water Resource and Protection》 2018年第6期539-558,共20页
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
关键词 Resources Protection TRADITIONAL water Bodies URBANIZATION GIS water Quality water Security
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Shallow Water Body Data Processing Based on the Seismic Oceanography 被引量:2
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作者 LIU Huaishan HU Yi +3 位作者 YIN Yanxin WANG Linfei TONG Siyou MA Hai 《Journal of Ocean University of China》 SCIE CAS 2013年第3期319-326,共8页
Physical properties of sea water,such as salinity,temperature,density and acoustic velocity,could be demarcated through degradation of energy caused by water absorption,attenuation and other factors.To overcome the ch... Physical properties of sea water,such as salinity,temperature,density and acoustic velocity,could be demarcated through degradation of energy caused by water absorption,attenuation and other factors.To overcome the challenging difficulties in the quick monitoring of these physical properties,we have explored the high resolution marine seismic survey to instantly characterize them.Based on the unique wavefield propagating in the sea water,we have developed a new approach to suppress the noise caused by the shallow sea water disturbance and obtain useful information for estimating the sea water structure.This approach improves seismic data with high signal-to-noise ratio and resolution.The seismic reflection imaging can map the sea water structure acoustically.Combined with the knowledge of local water body structure profile over years,the instant model for predicting the sea water properties could be built using the seismic data acquired from the specially designed high precision marine seismic acquisition.This model can also be updated with instant observation and the complete data processing system.The present study has the potential value to many applications,such as 3D sea water monitoring,engineering evaluation,geological disaster assessment and environmental assessment. 展开更多
关键词 数据处理系统 地震勘测 海洋学 水体 地震数据采集 海水结构 浅层 高分辨率
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Stand-Alone Photovoltaic System to Mitigate Pollution in Bodies of Water CASE Study: Laguna Del Carpintero, Tampico, Tamaulipas
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作者 Adán Hernández-Sánchez Josefina García-Navarro +2 位作者 María Esther Bautista-Vargas Santiago Gómez-Carpizo Raúl Hernández-Martínez 《Journal of Environmental Protection》 2015年第4期351-358,共8页
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
关键词 Photovoltaic System POLLUTION water AERATION BODIES of water Laguna de Carpintero
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Impact of Urban Land Transformation on Water Bodies in Srinagar City, India
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作者 Shahab Fazal Arshad Amin 《Journal of Environmental Protection》 2011年第2期142-153,共12页
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
关键词 Urban LAND TRANSFORMATION water BODIES AGRICULTURE Marshy
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