Performance evaluation of Normalized Difference Chlorophyll Index in northern Gulf of Mexico estuaries using the Hyperspectral Imager for the Coastal Ocean

EPA Science Inventory

The Hyperspectral Imager for the Coastal Ocean (HICO) was used to derive chlorophyll-a (chl-a) based on the Normalized Difference Chlorophyll Index (NDCI) in two Gulf of Mexico coastal estuaries. Chl-a data were acquired from discrete in-situ water sample analysis and above-water...

A Multi-Index Approach to Delineate Surface Water Bodies in the Pastoral Regions of Mali Using ASTER Imagery

NASA Astrophysics Data System (ADS)

Alemu, H.; Velpuri, N.; Senay, G. B.; Angerer, J.

2011-12-01

Information on the location and availability of water resources is a day-to-day challenge for pastoralists in the Sahelian region of Mali. They move seasonally along their migration corridors in search for water and forage. Satellite data can be used to map the spatial and temporal dynamics of these water resources. In this work, ASTER imagery is selected for its high (15 m) spatial resolution and suitable spectral bands for water body identification. Our research indicates that as most of the waterholes of interest in the study area are very shallow and heavily sediment-laden, using only one of those commonly used water identification indices such as the Simple Band Ratio (SBR), or the Normalized Difference Water Index (NDWI) alone does not help in effectively characterizing all the surface water bodies in the region. As a result, we used four different spectral indices to identify surface water features: (i) Simple Band Ratio (SBR), (ii) Normalized Difference Water Index (NDWI), (iii) Modified Normalized Difference Water Index (MNDWI), and (iv) the Mean Absolute Deviation (MAD) to identify and delineate surface water bodies using 91 ASTER images. Initial results indicate that the SBR method identified 17 waterholes while the NDWI 18, the MNDWI 36, and the MAD method identified 28 waterholes. However, by combining the results from the four aforementioned spectral indices following a multi-index approach, 89 waterholes that were previously unidentified by a single approach alone were identified. Furthermore, our analysis indicates that the SBR and the NDWI methods identify relatively clearer waterholes better (29% of the waterholes), whereas MNDWI and MAD proved to be good indices for identifying sediment-laden waterholes. Identifying the location and spatial distribution of surface water bodies is the first step towards monitoring their seasonal dynamics using a hydrologic modeling system, similar to an existing setup for east Africa (http://watermon.tamu.edu/). Seasonal trends in relative surface water levels are one of the most important inputs in the livestock early warning system (LEWS) along with forage and livestock market prices.

The effect of water vapour on the normalized difference vegetation index derived for the Sahelian region from NOAA AVHRR data

NASA Technical Reports Server (NTRS)

Justice, Christopher O.; Eck, T. F.; Tanre, Didier; Holben, B. N.

1991-01-01

The near-infrared channel of the NOAA advanced very high resolution radiometer (AVHRR) contains a water vapor absorption band that affects the determination of the normalized difference vegetation index (NDVI). Daily and seasonal variations in atmospheric water vapor within the Sahel are shown to affect the use of the NDVI for the estimation of primary production. This water vapor effect is quantified for the Sahel by radiative transfer modeling and empirically using observations made in Mali in 1986.

Effect of water content and organic carbon on remote sensing of crop residue cover

NASA Astrophysics Data System (ADS)

Serbin, G.; Hunt, E. R., Jr.; Daughtry, C. S. T.; McCarty, G. W.; Brown, D. J.; Doraiswamy, P. C.

2009-04-01

Crop residue cover is an important indicator of tillage method. Remote sensing of crop residue cover is an attractive and efficient method when compared with traditional ground-based methods, e.g., the line-point transect or windshield survey. A number of spectral indices have been devised for residue cover estimation. Of these, the most effective are those in the shortwave infrared portion of the spectrum, situated between 1950 and 2500 nm. These indices include the hyperspectral Cellulose Absorption Index (CAI), and advanced multispectral indices, i.e., the Lignin-Cellulose Absorption (LCA) index and the Shortwave Infrared Normalized Difference Residue Index (SINDRI), which were devised for the NASA Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor. Spectra of numerous soils from U.S. Corn Belt (Indiana and Iowa) were acquired under wetness conditions varying from saturation to oven-dry conditions. The behavior of soil reflectance with water content was also dependent on the soil organic carbon content (SOC) of the soils, and the location of the spectral bands relative to significant water absorptions. High-SOC soils showed the least change in spectral index values with increase in soil water content. Low-SOC soils, on the other hand, showed measurable difference. For CAI, low-SOC soils show an initial decrease in index value followed by an increase, due to the way that water content affects CAI spectral bands. Crop residue CAI values decrease with water content. For LCA, water content increases decrease crop residue index values and increase them for soils, resulting in decreased contrast. SINDRI is also affected by SOC and water content. As such, spatial information on the distribution of surface soil water content and SOC, when used in a geographic information system (GIS), will improve the accuracy of remotely-sensed crop residue cover estimates.

Water Quality Assessment for Deep-water Channel area of Guangzhou Port based on the Comprehensive Water Quality Identification Index Method

NASA Astrophysics Data System (ADS)

Chen, Yi

2018-03-01

The comprehensive water quality identification index method is able to assess the general water quality situation comprehensively and represent the water quality classification; water environment functional zone achieves pollution level and standard objectively and systematically. This paper selects 3 representative zones along deep-water channel of Guangzhou port and applies comprehensive water quality identification index method to calculate sea water quality monitoring data for different selected zones from year 2006 to 2014, in order to investigate the temporal variation of water quality along deep-water channel of Guangzhou port. The comprehensive water quality level from north to south presents an increased trend, and the water quality of the three zones in 2014 is much better than in 2006. This paper puts forward environmental protection measurements and suggestions for Pearl River Estuary, provides data support and theoretical basis for studied sea area pollution prevention and control.

Preliminary comparison of landscape pattern-normalized difference vegetation index (NDVI) relationships to central plains stream conditions

USGS Publications Warehouse

Griffith, J.A.; Martinko, E.A.; Whistler, J.L.; Price, K.P.

2002-01-01

We explored relationships of water quality parameters with landscape pattern metrics (LPMs), land use-land cover (LULC) proportions, and the advanced very high resolution radiometer (AVHRR) normalized difference vegetation index (NDVI) or NDVI-derived metrics. Stream sites (271) in Nebraska, Kansas, and Missouri were sampled for water quality parameters, the index of biotic integrity, and a habitat index in either 1994 or 1995. Although a combination of LPMs (interspersion and juxtaposition index, patch density, and percent forest) within Ozark Highlands watersheds explained >60% of the variation in levels of nitrite-nitrate nitrogen and conductivity, in most cases the LPMs were not significantly correlated with the stream data. Several problems using landscape pattern metrics were noted: small watersheds having only one or two patches, collinearity with LULC data, and counterintuitive or inconsistent results that resulted from basic differences in land use-land cover patterns among ecoregions or from other factors determining water quality. The amount of variation explained in water quality parameters using multiple regression models that combined LULC and LPMs was generally lower than that from NDVI or vegetation phenology metrics derived from time-series NDVI data. A comparison of LPMs and NDVI indicated that NDVI had greater promise for monitoring landscapes for stream conditions within the study area.

Preliminary comparison of landscape pattern-normalized difference vegetation index (NDVI) relationships to Central Plains stream conditions.

PubMed

Griffith, Jerry A; Martinko, Edward A; Whistler, Jerry L; Price, Kevin P

2002-01-01

We explored relationships of water quality parameters with landscape pattern metrics (LPMs), land use-land cover (LULC) proportions, and the advanced very high resolution radiometer (AVHRR) normalized difference vegetation index (NDVI) or NDVI-derived metrics. Stream sites (271) in Nebraska, Kansas, and Missouri were sampled for water quality parameters, the index of biotic integrity, and a habitat index in either 1994 or 1995. Although a combination of LPMs (interspersion and juxtaposition index, patch density, and percent forest) within Ozark Highlands watersheds explained >60% of the variation in levels of nitrite-nitrate nitrogen and conductivity, in most cases the LPMs were not significantly correlated with the stream data. Several problems using landscape pattern metrics were noted: small watersheds having only one or two patches, collinearity with LULC data, and counterintuitive or inconsistent results that resulted from basic differences in land use-land cover patterns among ecoregions or from other factors determining water quality. The amount of variation explained in water quality parameters using multiple regression models that combined LULC and LPMs was generally lower than that from NDVI or vegetation phenology metrics derived from time-series NDVI data. A comparison of LPMs and NDVI indicated that NDVI had greater promise for monitoring landscapes for stream conditions within the study area.

Wine grape cultivar influence on the performance of models that predict the lower threshold canopy temperature of a water stress index

USDA-ARS?s Scientific Manuscript database

The calculation of a thermal based Crop Water Stress Index (CWSI) requires an estimate of canopy temperature under non-water stressed conditions. The objective of this study was to assess the influence of different wine grape cultivars on the performance of models that predict canopy temperature non...

Equivalences between refractive index and equilibrium water content of conventional and silicone hydrogel soft contact lenses from automated and manual refractometry.

PubMed

González-Méijome, José M; López-Alemany, Antonio; Lira, Madalena; Almeida, José B; Oliveira, M Elisabete C D Real; Parafita, Manuel A

2007-01-01

The purpose of the present study was to develop mathematical relationships that allow obtaining equilibrium water content and refractive index of conventional and silicone hydrogel soft contact lenses from refractive index measures obtained with automated refractometry or equilibrium water content measures derived from manual refractometry, respectively. Twelve HEMA-based hydrogels of different hydration and four siloxane-based polymers were assayed. A manual refractometer and a digital refractometer were used. Polynomial models obtained from the sucrose curves of equilibrium water content against refractive index and vice-versa were used either considering the whole range of sucrose concentrations (16-100% equilibrium water content) or a range confined to the equilibrium water content of current soft contact lenses (approximately 20-80% equilibrium water content). Values of equilibrium water content measured with the Atago N-2E and those derived from the refractive index measurement with CLR 12-70 by the applications of sucrose-based models displayed a strong linear correlation (r2 = 0.978). The same correlations were obtained when the models are applied to obtain refractive index values from the Atago N-2E and compared with those (values) given by the CLR 12-70 (r2 = 0.978). No significantly different results are obtained between models derived from the whole range of the sucrose solution or the model limited to the normal range of soft contact lens hydration. Present results will have implications for future experimental and clinical research regarding normal hydration and dehydration experiments with hydrogel polymers, and particularly in the field of contact lenses. 2006 Wiley Periodicals, Inc.

Evaluation of automated urban surface water extraction from Sentinel-2A imagery using different water indices

NASA Astrophysics Data System (ADS)

Yang, Xiucheng; Chen, Li

2017-04-01

Urban surface water is characterized by complex surface continents and small size of water bodies, and the mapping of urban surface water is currently a challenging task. The moderate-resolution remote sensing satellites provide effective ways of monitoring surface water. This study conducts an exploratory evaluation on the performance of the newly available Sentinel-2A multispectral instrument (MSI) imagery for detecting urban surface water. An automatic framework that integrates pixel-level threshold adjustment and object-oriented segmentation is proposed. Based on the automated workflow, different combinations of visible, near infrared, and short-wave infrared bands in Sentinel-2 image via different water indices are first compared. Results show that object-level modified normalized difference water index (MNDWI with band 11) and automated water extraction index are feasible in urban surface water mapping for Sentinel-2 MSI imagery. Moreover, comparative results are obtained utilizing optimal MNDWI from Sentinel-2 and Landsat 8 images, respectively. Consequently, Sentinel-2 MSI achieves the kappa coefficient of 0.92, compared with that of 0.83 from Landsat 8 operational land imager.

Using Scientific Inquiry to Teach Students about Water Quality

ERIC Educational Resources Information Center

Puche, Helena; Holt, Jame

2012-01-01

This semi-guided inquiry activity explores the macroinvertebrate fauna in water sources affected by different levels of pollution. Students develop their ability to identify macroinvertebrates, compare aquatic fauna from different sources of water samples, evaluate water quality using an index, document and analyze data, raise questions and…

Land use policy and agricultural water management of the previous half of century in Africa

NASA Astrophysics Data System (ADS)

Valipour, Mohammad

2015-12-01

This paper examines land use policy and agricultural water management in Africa from 1962 to 2011. For this purpose, data were gathered from Food and Agriculture Organization of the United Nations (FAO) and the World Bank Group. Using the FAO database, ten indices were selected: permanent crops to cultivated area (%), rural population to total population (%), total economically active population in agriculture to total economically active population (%), human development index, national rainfall index (mm/year), value added to gross domestic product by agriculture (%), irrigation water requirement (mm/year), percentage of total cultivated area drained (%), difference between national rainfall index and irrigation water requirement (mm/year), area equipped for irrigation to cultivated area or land use policy index (%). These indices were analyzed for all 53 countries in the study area and the land use policy index was estimated by two different formulas. The results show that value of relative error is <20 %. In addition, an average index was calculated using various methods to assess countries' conditions for agricultural water management. Ability of irrigation and drainage systems was studied using other eight indices with more limited information. These indices are surface irrigation (%), sprinkler irrigation (%), localized irrigation (%), spate irrigation (%), agricultural water withdrawal (10 km3/year), conservation agriculture area as percentage of cultivated area (%), percentage of area equipped for irrigation salinized (%), and area waterlogged by irrigation (%). Finally, tendency of farmers to use irrigation systems for cultivated crops has been presented. The results show that Africa needs governments' policy to encourage farmers to use irrigation systems and raise cropping intensity for irrigated area.

Retrieval of canopy water content of different crop types with two new hyperspectral indices: Water Absorption Area Index and Depth Water Index

NASA Astrophysics Data System (ADS)

Pasqualotto, Nieves; Delegido, Jesús; Van Wittenberghe, Shari; Verrelst, Jochem; Rivera, Juan Pablo; Moreno, José

2018-05-01

Crop canopy water content (CWC) is an essential indicator of the crop's physiological state. While a diverse range of vegetation indices have earlier been developed for the remote estimation of CWC, most of them are defined for specific crop types and areas, making them less universally applicable. We propose two new water content indices applicable to a wide variety of crop types, allowing to derive CWC maps at a large spatial scale. These indices were developed based on PROSAIL simulations and then optimized with an experimental dataset (SPARC03; Barrax, Spain). This dataset consists of water content and other biophysical variables for five common crop types (lucerne, corn, potato, sugar beet and onion) and corresponding top-of-canopy (TOC) reflectance spectra acquired by the hyperspectral HyMap airborne sensor. First, commonly used water content index formulations were analysed and validated for the variety of crops, overall resulting in a R2 lower than 0.6. In an attempt to move towards more generically applicable indices, the two new CWC indices exploit the principal water absorption features in the near-infrared by using multiple bands sensitive to water content. We propose the Water Absorption Area Index (WAAI) as the difference between the area under the null water content of TOC reflectance (reference line) simulated with PROSAIL and the area under measured TOC reflectance between 911 and 1271 nm. We also propose the Depth Water Index (DWI), a simplified four-band index based on the spectral depths produced by the water absorption at 970 and 1200 nm and two reference bands. Both the WAAI and DWI outperform established indices in predicting CWC when applied to heterogeneous croplands, with a R2 of 0.8 and 0.7, respectively, using an exponential fit. However, these indices did not perform well for species with a low fractional vegetation cover (<30%). HyMap CWC maps calculated with both indices are shown for the Barrax region. The results confirmed the potential of using generically applicable indices for calculating CWC over a great variety of crops.

[Comparition of ecological security stress effects of artificial landscapes on natural landscapes in different rapid urban sprawl areas].

PubMed

Lin, Mei Xia; Lin, Tao; Qiu, Quan Yi; Sun, Cai Ge; Deng, Fu Liang; Zhang, Guo Qin

2017-04-18

The expansion of built-up area will cause stress effect on the regional natural ecological security pattern during urbanization process. Taking rapid expanding regions of four inland and coastal cities as study areas, including Tongzhou in Beijing, Zhengding in Hebei, Tanggu in Tianjin and Xiamen in Fujian, we constructed regional landscape stress indexes according to the principle of landscape ecology and comparatively analyzed the landscape pattern characteristics of rapid expanding regions and the differences of stress effect of artificial landscapes on four natural landscapes ecological security pattern in the process of rapid urbanization. Results showed that landscape erosion indexes of Tongzhou, Zhengding, Tanggu and Xiamen in 2015 were 1.039, 0.996, 1.239 and 0.945, respectively, which indicated that the natural landscapes were eroded significantly. Natural landscape types of those four regions presented different threatened levels. Among all natural landscape types, unused land and waters were worst threatened in Tongzhou, Zhengding and Tanggu, while in Xiamen cultivated land and waters showed the highest threat levels. The waters threat indexes of those four areas were all more than 0.743. Landscape isolation indexes of waters and unused land of the inland cities were greater than those of coastal cities, which meant water distribution of inland cities in the space was less gathered than that of coastal cities. Besides, compared with the other natural landscape, unused land and waters suffered the largest stress from artificial landscapes.

Assessing corn water stress using spectral reflectance

NASA Astrophysics Data System (ADS)

Mefford, Brenna S.

Multiple remote sensing techniques have been developed to identify crop water stress, but some methods may be difficult for farmers to apply. Unlike most techniques, shortwave vegetation indices can be calculated using satellite, aerial, or ground imagery from the green (525-600 nm), red (625-700 nm), and near infrared (750-900 nm) spectral bands. If vegetation indices can be used to monitor crop water stress, growers could use this information as a quick low-cost guideline for irrigation management, thus helping save water by preventing over irrigating. This study occurred in the 2013 growing season near Greeley, CO, where pressurized drip irrigation was used to irrigate twelve corn ( Zea mays L.) treatments of varying water deficit. Multispectral data was collected and four different vegetation indices were evaluated: Normalized Difference Vegetation Index (NDVI), Optimized Soil-Adjusted Vegetation Index (OSAVI), Green Normalized Difference Vegetation Index (GNDVI), and the Wide Dynamic Range Vegetation Index (WDRVI). The four vegetation indices were compared to corn water stress as indicated by the stress coefficient (Ks) and water deficit in the root zone, calculated by using a water balance that monitors crop evapotranspiration (ET), irrigation events, precipitation events, and deep percolation. ET for the water balance was calculated using two different methods for comparison purposes: (1) calculation of the stress coefficient (Ks) using FAO-56 standard procedures; (2) use of canopy temperature ratio (Tc ratio) of a stressed crop to a non-stressed crop to calculate Ks. It was found that obtaining Ks from Tc ratio is a viable option, and requires less data to obtain than Ks from FAO-56. In order to compare the indices to Ks, vegetation ratios were developed in the process of normalization. Vegetation ratios are defined as the non-stressed vegetation index divided by the stressed vegetation index. Results showed that vegetation ratios were sensitive to water stress as indicated by good R2 values (Nratio = 0.53, G ratio=0.46, Oratio=0.49) and low RMSE values (Nratio = 0.076, Gratio=0.062, Oratio=0.076) when compared to Ks. Therefore it can be concluded that corn spectral reflectance is sensitive to water stress. In order to use spectral reflectance to manage crop water stress an irrigation trigger point of 0.93 for the vegetation ratios was determined. These results were validated using data collected by a MSR5 multispectral sensor in an adjacent field (SWIIM Field). The results from the second field proved better than in the main field giving higher R 2 values (Nratio = 0.66, Gratio = 0.63, Oratio = 0.66), and lower RMSE values (Nratio = 0.043, Gratio = 0.036, Oratio = 0.043) between Ks and the vegetation indices. SWIIM field further validated the results that spectral reflectance can be used to monitor corn water stress.

A genetic fuzzy analytical hierarchy process based projection pursuit method for selecting schemes of water transportation projects

NASA Astrophysics Data System (ADS)

Jin, Juliang; Li, Lei; Wang, Wensheng; Zhang, Ming

2006-10-01

The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of importance in both theory and practice in water resource systems engineering. In order to achieve consistency and eliminate the dimensions of fuzzy qualitative and fuzzy quantitative evaluation indexes, to determine the weights of the indexes objectively, and to increase the differences among the comprehensive evaluation index values of water transportation project schemes, a projection pursuit method, named FPRM-PP for short, was developed in this work for selecting the optimal water transportation project scheme based on the fuzzy preference relation matrix. The research results show that FPRM-PP is intuitive and practical, the correction range of the fuzzy preference relation matrix A it produces is relatively small, and the result obtained is both stable and accurate; therefore FPRM-PP can be widely used in the optimal selection of different multi-factor decision-making schemes.

Assessing clarity of message communication for mandated USEPA drinking water quality reports.

PubMed

Phetxumphou, Katherine; Roy, Siddhartha; Davy, Brenda M; Estabrooks, Paul A; You, Wen; Dietrich, Andrea M

2016-04-01

The United States Environmental Protection Agency mandates that community water systems (CWSs), or drinking water utilities, provide annual consumer confidence reports (CCRs) reporting on water quality, compliance with regulations, source water, and consumer education. While certain report formats are prescribed, there are no criteria ensuring that consumers understand messages in these reports. To assess clarity of message, trained raters evaluated a national sample of 30 CCRs using the Centers for Disease Control Clear Communication Index (Index) indices: (1) Main Message/Call to Action; (2) Language; (3) Information Design; (4) State of the Science; (5) Behavioral Recommendations; (6) Numbers; and (7) Risk. Communication materials are considered qualifying if they achieve a 90% Index score. Overall mean score across CCRs was 50 ± 14% and none scored 90% or higher. CCRs did not differ significantly by water system size. State of the Science (3 ± 15%) and Behavioral Recommendations (77 ± 36%) indices were the lowest and highest, respectively. Only 63% of CCRs explicitly stated if the water was safe to drink according to federal and state standards and regulations. None of the CCRs had passing Index scores, signaling that CWSs are not effectively communicating with their consumers; thus, the Index can serve as an evaluation tool for CCR effectiveness and a guide to improve water quality communications.

Using Panchromatic Imagery in Place of Multispectral Imagery for Kelp Detection in Water

DTIC Science & Technology

2010-01-01

Normalized Difference Vegetation Index ( NDVI ). In broadband panchromatic imagery, the kelp appears brighter than the water because of the strong...response of vegetation in the NIR, and can be reliably detected by means of a simple threshold; overall brightness is generally proportional to the NDVI ...Index ( NDVI ). In broadband panchromatic imagery, the kelp appears brighter than the water because of the strong response of vegetation in the NIR, and

Evaluating the potential of vegetation indices for winter wheat LAI estimation under different fertilization and water conditions

NASA Astrophysics Data System (ADS)

Xie, Qiaoyun; Huang, Wenjiang; Dash, Jadunandan; Song, Xiaoyu; Huang, Linsheng; Zhao, Jinling; Wang, Renhong

2015-12-01

Leaf area index (LAI) is an important indicator for monitoring crop growth conditions and forecasting grain yield. Many algorithms have been developed for remote estimation of the leaf area index of vegetation, such as using spectral vegetation indices, inversion of radiative transfer models, and supervised learning techniques. Spectral vegetation indices, mathematical combination of reflectance bands, are widely used for LAI estimation due to their computational simplicity and their applications ranged from the leaf scale to the entire globe. However, in many cases, their applicability is limited to specific vegetation types or local conditions due to species specific nature of the relationship used to transfer the vegetation indices to LAI. The overall objective of this study is to investigate the most suitable vegetation index for estimating winter wheat LAI under eight different types of fertilizer and irrigation conditions. Regression models were used to estimate LAI using hyperspectral reflectance data from the Pushbroom Hyperspectral Imager (PHI) and in-situ measurements. Our results showed that, among six vegetation indices investigated, the modified soil-adjusted vegetation index (MSAVI) and the normalized difference vegetation index (NDVI) exhibited strong and significant relationships with LAI, and thus were sensitive across different nitrogen and water treatments. The modified triangular vegetation index (MTVI2) confirmed its potential on crop LAI estimation, although second to MSAVI and NDVI in our study. The enhanced vegetation index (EVI) showed moderate performance. However, the ratio vegetation index (RVI) and the modified simple ratio index (MSR) predicted the least accurate estimations of LAI, exposing the simple band ratio index's weakness under different treatment conditions. The results support the use of vegetation indices for a quick and effective LAI mapping procedure that is suitable for winter wheat under different management practices.

a Framework of Change Detection Based on Combined Morphologica Features and Multi-Index Classification

NASA Astrophysics Data System (ADS)

Li, S.; Zhang, S.; Yang, D.

2017-09-01

Remote sensing images are particularly well suited for analysis of land cover change. In this paper, we present a new framework for detection of changing land cover using satellite imagery. Morphological features and a multi-index are used to extract typical objects from the imagery, including vegetation, water, bare land, buildings, and roads. Our method, based on connected domains, is different from traditional methods; it uses image segmentation to extract morphological features, while the enhanced vegetation index (EVI), the differential water index (NDWI) are used to extract vegetation and water, and a fragmentation index is used to the correct extraction results of water. HSV transformation and threshold segmentation extract and remove the effects of shadows on extraction results. Change detection is performed on these results. One of the advantages of the proposed framework is that semantic information is extracted automatically using low-level morphological features and indexes. Another advantage is that the proposed method detects specific types of change without any training samples. A test on ZY-3 images demonstrates that our framework has a promising capability to detect change.

Gas exchange and antioxidant activity in seedlings of C opaifera langsdorffii Desf. under different water conditions.

PubMed

Rosa, Derek B C J; Scalon, Silvana P Q; Cremon, Thais; Ceccon, Felipe; Dresch, Daiane M

2017-01-01

The aim of this study was to evaluate gas exchange, efficiency of the photosynthetic apparatus, and antioxidant activity in Copaifera langsdorffii Desf. The seedlings were cultivated under different conditions of water availability, in order to improve the utilization efficiency of available water resources. The seedlings were cultivated in four different water retention capacities (WRC- 25%, 50%, 75%, and 100%), and evaluated at four different time (T- 30, 60, 90, and 120 days). During the experimental period, seedlings presented the highest values for carboxylation efficiency of Rubisco (A/Ci), intrinsic water use efficiency (IWUE = A/gs), chlorophyll index, and stomatal opening, when grown in the substrate with 75% WRC, but the stomatal index (SI) was less the 25% WRC. The efficiency of photosystem II was not significantly altered by the treatments. Comparison between the extreme treatments in terms of water availability, represented by 25% and 100% WRC, represent stress conditions for the species. Water availability causes a high activity of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase) in the plant.

Assess water scarcity integrating water quantity and quality

NASA Astrophysics Data System (ADS)

Liu, J.; Zeng, Z.

2014-12-01

Water scarcity has become widespread all over the world. Current methods for water scarcity assessment are mainly based on water quantity and seldom consider water quality. Here, we develop an approach for assessing water scarcity considering both water quantity and quality. In this approach, a new water scarcity index is used to describe the severity of water scarcity in the form of a water scarcity meter, which may help to communicate water scarcity to a wider audience. To illustrate the approach, we analyzed the historical trend of water scarcity for Beijing city in China during 1995-2009, as well as the assessment for different river basins in China. The results show that Beijing made a huge progress in mitigating water scarcity, and that from 1999 to 2009 the blue and grey water scarcity index decreased by 59% and 62%, respectively. Despite this progress, we demonstrate that Beijing is still characterized by serious water scarcity due to both water quantity and quality. The water scarcity index remained at a high value of 3.5 with a blue and grey water scarcity index of 1.2 and 2.3 in 2009 (exceeding the thresholds of 0.4 and 1, respectively). As a result of unsustainable water use and pollution, groundwater levels continue to decline, and water quality shows a continuously deteriorating trend. To curb this trend, future water policies should further decrease water withdrawal from local sources (in particular groundwater) within Beijing, and should limit the grey water footprint below the total amount of water resources.

A Generalized Framework for Different Drought Indices: Testing its Suitability in a Simulation of the last two Millennia for Europe

NASA Astrophysics Data System (ADS)

Raible, Christoph C.; Baerenbold, Oliver; Gomez-Navarro, Juan Jose

2016-04-01

Over the past decades, different drought indices have been suggested in the literature. This study tackles the problem of how to characterize drought by defining a general framework and proposing a generalized family of drought indices that is flexible regarding the use of different water balance models. The sensitivity of various indices and its skill to represent drought conditions is evaluated using a regional model simulation in Europe spanning the last two millennia as test bed. The framework combines an exponentially damped memory with a normalization method based on quantile mapping. Both approaches are more robust and physically meaningful compared to the existing methods used to define drought indices. Still, framework is flexible with respect to the water balance, enabling users to adapt the index formulation to the data availability of different locations. Based on the framework, indices with different complex water balances are compared with each other. The comparison shows that a drought index considering only precipitation in the water balance is sufficient for Western to Central Europe. However, in the Mediterranean temperature effects via evapotranspiration need to be considered in order to produce meaningful indices representative of actual water deficit. Similarly, our results indicate that in north-eastern Europe and Scandinavia, snow and runoff effects needs to be considered in the index definition to obtain accurate results.

Construction of an evaluation index system of water resources bearing capacity: An empirical study in Xi’an, China

NASA Astrophysics Data System (ADS)

Qu, X. E.; Zhang, L. L.

2017-08-01

In this paper, a comprehensive evaluation of the water resources bearing capacity of Xi’an is performed. By constructing a comprehensive evaluation index system of the water resources bearing capacity that included water resources, economy, society, and ecological environment, we empirically studied the dynamic change and regional differences of the water resources bearing capacities of Xi’an districts through the TOPSIS method (Technique for Order Preference by Similarity to an Ideal Solution). Results show that the water resources bearing capacity of Xi’an significantly increased over time, and the contributions of the subsystems from high to low are as follows: water resources subsystem, social subsystem, ecological subsystem, and economic subsystem. Furthermore, there are large differences between the water resources bearing capacities of the different districts in Xi’an. The water resources bearing capacities from high to low are urban areas, Huxian, Zhouzhi, Gaoling, and Lantian. Overall, the water resources bearing capacity of Xi’an is still at a the lower level, which is highly related to the scarcity of water resources, population pressure, insufficient water saving consciousness, irrational industrial structure, low water-use efficiency, and so on.

Evaluating the ameliorative effect of natural dissolved organic matter (DOM) quality on copper toxicity to Daphnia magna: improving the BLM.

PubMed

Al-Reasi, Hassan A; Smith, D Scott; Wood, Chris M

2012-03-01

Various quality predictors of seven different natural dissolved organic matter (DOM) and humic substances were evaluated for their influence on protection of Daphnia magna neonates against copper (Cu) toxicity. Protection was examined at 3 and 6 mg l(-1) of dissolved organic carbon (DOC) of each DOM isolate added to moderately hard, dechlorinated water. Other water chemistry parameters (pH, concentrations of DOC, calcium, magnesium and sodium) were kept relatively constant. Predictors included absorbance ratios Abs(254/365) (index of molecular weight) and Abs-octanol(254)/Abs-water(254) (index of lipophilicity), specific absorption coefficient (SAC(340); index of aromaticity), and fluorescence index (FI; index of source). In addition, the fluorescent components (humic-like, fulvic-like, tryptophan-like, and tyrosine-like) of the isolates were quantified by parallel factor analysis (PARAFAC). Up to 4-fold source-dependent differences in protection were observed amongst the different DOMs. Significant correlations in toxicity amelioration were found with Abs(254/365), Abs-octanol(254)/Abs-water(254), SAC(340), and with the humic-like fluorescent component. The relationships with FI were not significant and there were no relationships with the tryptophan-like or tyrosine-like fluorescent components at 3 mg C l(-1), whereas a negative correlation was seen with the fulvic-like component. In general, the results indicate that larger, optically dark, more lipophilic, more aromatic DOMs of terrigenous origin, with higher humic-like content, are more protective against Cu toxicity. A method for incorporating SAC(340) as a DOM quality indicator into the Biotic Ligand Model is presented; this may increase the accuracy for predicting Cu toxicity in natural waters.

Contact lens material characteristics associated with hydrogel lens dehydration.

PubMed

Ramamoorthy, Padmapriya; Sinnott, Loraine T; Nichols, Jason J

2010-03-01

To determine the association between material dehydration and hydrogel contact lens material characteristics, including water content and ionicity. Water content and refractive index data were derived from automated refractometry measurements of worn hydrogel contact lenses of 318 participants in the Contact Lens and Dry Eye Study (CLADES). Dehydration was determined in two ways; as the difference between nominal and measured (1) water content and (2) refractive index. Multiple regression models were used to examine the relation between dehydration and material characteristics, controlling for tear osmolality. The overall measured and nominal water content values were 52.58 +/- 7.49% and 56.88 +/- 7.81% respectively, while the measured and nominal refractive indices were 1.429 +/- 0.015 and 1.410 +/- 0.017. High water content and ionic hydrogel lens materials were associated with greater dehydration (p < 0.0001 for both) than low water content and non-ionic materials. When dehydration was assessed as the difference in refractive index, only high water content was associated with dehydration (p < 0.0001). High water content and ionic characteristics of hydrogel lens materials are associated with hydrogel lens dehydration, with the former being more strongly associated. Such dehydration changes could in turn lead to important clinical ramifications such as reduced oxygen transmissibility, greater lens adherence and reduced tear exchange.

Modified Optimization Water Index (mowi) for LANDSAT-8 Oli/tirs

NASA Astrophysics Data System (ADS)

Moradi, M.; Sahebi, M.; Shokri, M.

2017-09-01

Water is one of the most important resources that essential need for human life. Due to population growth and increasing need of human to water, proper management of water resources will be one of the serious challenges of next decades. Remote sensing data is the best way to the management of water resources due time and cost effectiveness over a greater range of temporal and spatial scales. Between many kinds of satellite data, from SAR to optic or from high resolution to low resolution, Landsat imagery is more interesting data for water detection and management of earth surface water. Landsat8 OLI/TIRS is the newest version of Landsat satellite series. In this paper, we investigated the full spectral potential of Landsat8 for water detection. It is developed many kinds of methods for this purpose that index based methods have some advantages than other methods. Pervious indices just use a limited number of spectral band. In this paper, Modified Optimization Water Index (MOWI) defined by consideration of a linear combination of bands that each coefficient of bands calculated by particle swarm algorithm. The result shows that modified optimization water index (MOWI) has a proper performance on different condition like cloud, cloud shadow and mountain shadow.

Relative sensitivity of Normalized Difference Vegetation Index (NDVI) and Microwave Polarization Difference Index (MPDI) for vegetation and desertification monitoring

NASA Technical Reports Server (NTRS)

Becker, Francois; Choudhury, Bhaskar J.

1988-01-01

A simple equation relating the Microwave Polarization Difference Index (MPDI) and the Normalized Difference Vegetation Index (NDVI) is proposed which represents well data obtained from Nimbus 7/SMMR at 37 GHz and NOAA/AVHRR Channels 1 and 2. It is found that there is a limit which is characteristic of a particular type of cover for which both indices are equally sensitive to the variation of vegetation, and below which MPDI is more efficient than NDVI. The results provide insight into the relationship between water content and chlorophyll absorption at pixel size scales.

Development of a benthic multimetric index for the Serra da Bocaina bioregion in Southeast Brazil.

PubMed

Baptista, D F; Henriques-Oliveira, A L; Oliveira, R B S; Mugnai, R; Nessimian, J L; Buss, D F

2013-08-01

Brazil faces a challenge to develop biomonitoring tools to be used in water quality assessment programs, but few multimetric indices were developed so far. This study is part of an effort to test and implement programs using benthic macroinvertebrates as bioindicators in Rio de Janeiro State. Our aim was first to test the Multimetric Index for Serra dos Órgãos (SOMI) for a different area--Serra da Bocaina (SB)--in the same ecoregion. We sampled 27 streams of different sizes and altitudes in the SB region. Despite the environmental similarities, results indicated biological differences between reference sites of the two regions. Considering these differences, we decided to develop an index specific for the SB region, the Serra da Bocaina Multimetric Index (MISB). We tested twenty-two metrics for sensitivity to impairment and redundancy, and six metrics were considered valid to integrate the MISB: Family Richness, Trichoptera Richness, % Coleoptera, % Diptera, IBE-IOC index, EPT / Chironomidae ratio. A test of the MISB in eleven sites indicated it was more related to land-use and water physico-chemical parameters than with altitude or stream width, being a useful tool for the monitoring and assessment of streams in the bioregion.

The Effect of Vegetation on Soil Water Infiltration and Retention Capacity by Improving Soil Physiochemical Property in Semi-arid Grassland

NASA Astrophysics Data System (ADS)

A, Y.; Wang, G.

2017-12-01

Water shortage is the main limiting factor for semi-arid grassland development. However, the grassland are gradually degraded represented by species conversion, biomass decrease and ecosystem structure simplification under the influence of human activity. Soil water characteristics such as moisture, infiltration and conductivity are critical variables affecting the interactions between soil parameters and vegetation. In this study, Cover, Height, Shannon-Wiener diversity index, Pielou evenness index and Richness index are served as indexes of vegetation productivity and community structure. And saturated hydraulic conductivity (Ks) and soil moisture content are served as indexes of soil water characters. The interaction between vegetation and soil water is investigated through other soil parameters, such as soil organic matter content at different vertical depths and in different degradation area (e.g., initial, transition and degraded plots). The results show that Ks significantly controlled by soil texture other than soil organic matter content. So the influence of vegetation on Ks through increasing soil organic content (SOM) might be slight. However, soil moisture content (SMC) appeared significantly positive relationship with SOM and silt content and negative relationship with sand content at all depth, significantly. This indicated that capacity of soil water storage was influenced both by soil texture and organic matter. In addition, the highest correlation coefficient of SMC was with SOM at the sub-surficial soil layer (20 40 cm). At the depth of 20 40 cm, the soil water content was relatively steady which slightly influenced by precipitation and evaporation. But it significantly influenced by soil organic matter content which related to vegetation. The correlation coefficient between SOM and SMC at topsoil layer (0 20 cm) was lowest (R2=0.36, p<0.01), which indicated the influence of vegetation on soil water content not only by soil organic matter content but also the other influential factors, such as the root water uptake, precipitation and evaporation.

Prevalence of dental fluorosis in relation with different fluoride levels in drinking water among school going children in Sarada tehsil of Udaipur district, Rajasthan.

PubMed

Sarvaiya, B U; Bhayya, D; Arora, R; Mehta, D N

2012-01-01

To estimate the prevalence of dental fluorosis in relation with different fluoride levels in drinking water among school going children of 6-12 years age group. Dental fluorosis was recorded using Dean's index in school children of selected villages. The drinking water samples of all the selected villages were collected in polyethylene bottles and the fluoride content of these samples was determined by fluoride ion selective method using Orion microprocessor analyser. The overall prevalence of dental fluorosis was found to be 69.84%. An increase in the community fluorosis index (CFI) with corresponding increase in water fluoride content was found. There was an increase in prevalence of dental fluorosis with a corresponding increase in water fluoride content from 0.8 ppm to 4.1 ppm. A significantly strong positive correlation was found between CFI and fluoride concentration in drinking water.

Modeling gross primary production in semi-arid Inner Mongolia using MODIS imagery and eddy covariance data

Treesearch

Ranjeet John; Jiquan Chen; Asko Noormets; Xiangming Xiao; Jianye Xu; Nan Lu; Shiping Chen

2013-01-01

We evaluate the modelling of carbon fluxes from eddy covariance (EC) tower observations in different water-limited land-cover/land-use (LCLU) and biome types in semi-arid Inner Mongolia, China. The vegetation photosynthesis model (VPM) and modified VPM (MVPM), driven by the enhanced vegetation index (EVI) and land-surface water index (LSWI), which were derived from the...

Terahertz time-domain spectroscopy of submonolayer water adsorption in hydrophilic silica aerogel.

PubMed

Zhang, Jiangquan; Grischkowsky, Daniel

2004-05-01

We report a terahertz time-domain spectroscopy study of the adsorption of water in hydrophilic silica aerogel. The adsorbed water is in submonolayer form and shows properties of index of refraction similar to those of bulk water but different absorption properties.

Evaluation of water quality index for River Sabarmati, Gujarat, India

NASA Astrophysics Data System (ADS)

Shah, Kosha A.; Joshi, Geeta S.

2017-06-01

An attempt has been made to develop water quality index (WQI), using six water quality parameters pH, dissolved oxygen, biochemical oxygen demand, electrical conductivity, nitrate nitrogen and total coliform measured at three different stations along the Sabarmati river basin from the year 2005 to 2008. Rating scale is developed based on the tolerance limits of inland waters and health point of view. Weighted arithmetic water quality index method was used to find WQI along the stretch of the river basin. It was observed from this study that the impact of human activity and sewage disposal in the river was severe on most of the parameters. The station located in highly urban area showed the worst water quality followed by the station located in moderately urban area and lastly station located in a moderately rural area. It was observed that the main cause of deterioration in water quality was due to the high anthropogenic activities, illegal discharge of sewage and industrial effluent, lack of proper sanitation, unprotected river sites and urban runoff.

Assessing the performance of wave breaking parameterizations in shallow waters in spectral wave models

NASA Astrophysics Data System (ADS)

Lin, Shangfei; Sheng, Jinyu

2017-12-01

Depth-induced wave breaking is the primary dissipation mechanism for ocean surface waves in shallow waters. Different parametrizations were developed for parameterizing depth-induced wave breaking process in ocean surface wave models. The performance of six commonly-used parameterizations in simulating significant wave heights (SWHs) is assessed in this study. The main differences between these six parameterizations are representations of the breaker index and the fraction of breaking waves. Laboratory and field observations consisting of 882 cases from 14 sources of published observational data are used in the assessment. We demonstrate that the six parameterizations have reasonable performance in parameterizing depth-induced wave breaking in shallow waters, but with their own limitations and drawbacks. The widely-used parameterization suggested by Battjes and Janssen (1978, BJ78) has a drawback of underpredicting the SWHs in the locally-generated wave conditions and overpredicting in the remotely-generated wave conditions over flat bottoms. The drawback of BJ78 was addressed by a parameterization suggested by Salmon et al. (2015, SA15). But SA15 had relatively larger errors in SWHs over sloping bottoms than BJ78. We follow SA15 and propose a new parameterization with a dependence of the breaker index on the normalized water depth in deep waters similar to SA15. In shallow waters, the breaker index of the new parameterization has a nonlinear dependence on the local bottom slope rather than the linear dependence used in SA15. Overall, this new parameterization has the best performance with an average scatter index of ∼8.2% in comparison with the three best performing existing parameterizations with the average scatter index between 9.2% and 13.6%.

Mapping of Biophysical Parameters of Rice Agriculture System from Hyperspectral Imagery

NASA Astrophysics Data System (ADS)

Moharana, Shreedevi; Duta, Subashisa

2017-04-01

Chlorophyll, nitrogen and leaf water content are the most essential parameters for paddy crop growth. Ground hyperspectral observations were collected at canopy level during critical growth period of rice by using hand held Spectroradiometer. Chemical analysis was carried out to quantify the total chlorophyll, nitrogen and leaf water content. By exploiting the in-situ hyperspectral measurements, regression models were established between each of the crop growth parameters and the spectral indices specifically designed for chlorophyll, nitrogen and water stress. Narrow band vegetation index models were developed for mapping these parameters from Hyperion imagery in an agriculture system. It was inferred that the modified simple ratio (SR) and leaf nitrogen concentration (LNC) predictive index models, which followed a linear and nonlinear relationship respectively, produced satisfactory results in predicting rice nitrogen content from hyperspectral imagery. The presently developed model was compared with other models proposed by researchers. It was ascertained that, nitrogen content varied widely from 1-4 percentage and only 2-3 percentage for paddy crop using present modified index models and well-known predicted Tian et al. (2011) model respectively. The modified present LNC index model performed better than the established Tian et al. (2011) model as far as the estimated nitrogen content from Hyperion imagery was concerned. Moreover, within the observed chlorophyll range attained from the rice genotypes cultivated in the studied rice agriculture system, the index models (LNC, OASVI, Gitelson, mSR and MTCI) accomplished satisfactory results in the spatial distribution of rice chlorophyll content from Hyperion imagery. Spatial distribution of total chlorophyll content widely varied from 1.77-5.81 mg/g (LNC), 3.0-13 mg/g (OASVI) and 2.90-5.40 mg/g (MTCI). Following the similar guideline, it was found that normalized difference water index (NDWI) and normalized difference infrared index (NDII) predictive models demonstrated the spatial variability of leaf water content from 40 percentage to 90 percentage in the same rice agriculture system which has a good agreement with observed in-situ leaf water measurements. The spatial information of these parameters will be useful for crop nutrient management and yield forecasting, and will serve as inputs to various crop-forecasting models for developing a precision rice agriculture system. Key words: Rice agriculture system, nitrogen, chlorophyll, leaf water content, vegetation index

Automatic design of basin-specific drought indexes for highly regulated water systems

NASA Astrophysics Data System (ADS)

Zaniolo, Marta; Giuliani, Matteo; Castelletti, Andrea Francesco; Pulido-Velazquez, Manuel

2018-04-01

Socio-economic costs of drought are progressively increasing worldwide due to undergoing alterations of hydro-meteorological regimes induced by climate change. Although drought management is largely studied in the literature, traditional drought indexes often fail at detecting critical events in highly regulated systems, where natural water availability is conditioned by the operation of water infrastructures such as dams, diversions, and pumping wells. Here, ad hoc index formulations are usually adopted based on empirical combinations of several, supposed-to-be significant, hydro-meteorological variables. These customized formulations, however, while effective in the design basin, can hardly be generalized and transferred to different contexts. In this study, we contribute FRIDA (FRamework for Index-based Drought Analysis), a novel framework for the automatic design of basin-customized drought indexes. In contrast to ad hoc empirical approaches, FRIDA is fully automated, generalizable, and portable across different basins. FRIDA builds an index representing a surrogate of the drought conditions of the basin, computed by combining all the relevant available information about the water circulating in the system identified by means of a feature extraction algorithm. We used the Wrapper for Quasi-Equally Informative Subset Selection (W-QEISS), which features a multi-objective evolutionary algorithm to find Pareto-efficient subsets of variables by maximizing the wrapper accuracy, minimizing the number of selected variables, and optimizing relevance and redundancy of the subset. The preferred variable subset is selected among the efficient solutions and used to formulate the final index according to alternative model structures. We apply FRIDA to the case study of the Jucar river basin (Spain), a drought-prone and highly regulated Mediterranean water resource system, where an advanced drought management plan relying on the formulation of an ad hoc state index is used for triggering drought management measures. The state index was constructed empirically with a trial-and-error process begun in the 1980s and finalized in 2007, guided by the experts from the Confederación Hidrográfica del Júcar (CHJ). Our results show that the automated variable selection outcomes align with CHJ's 25-year-long empirical refinement. In addition, the resultant FRIDA index outperforms the official State Index in terms of accuracy in reproducing the target variable and cardinality of the selected inputs set.

Validity of total and segmental impedance measurements for prediction of body composition across ethnic population groups.

PubMed

Deurenberg, P; Deurenberg-Yap, M; Schouten, F J M

2002-03-01

To test the impact of body build factors on the validity of impedance-based body composition predictions across (ethnic) population groups and to study the suitability of segmental impedance measurements. Cross-sectional observational study. Ministry of Health and School of Physical Education, Nanyang Technological University, Singapore. A total of 291 female and male Chinese, Malays and Indian Singaporeans, aged 18-69, body mass index (BMI) 16.0-40.2 kg/ m2. Anthropometric parameters were measured in addition to impedance (100 kHz) of the total body, arms and legs. Impedance indexes were calculated as height2/impedance. Arm length (span) and leg length (sitting height), wrist and knee width were measured from which body build indices were calculated. Total body water (TBW) was measured using deuterium oxide dilution. Extra cellular water (ECW) was measured using bromide dilution. Body fat percentage was determined using a chemical four-compartment model. The bias of TBW predicted from total body impedance index (bias: measured minus predicted TBW) was different among the three ethnic groups, TBW being significantly underestimated in Indians compared to Chinese and Malays. This bias was found to be dependent on body water distribution (ECW/TBW) and parameters of body build, mainly relative (to height) arm length. After correcting for differences in body water distribution and body build parameters the differences in bias across the ethnic groups disappeared. The impedance index using total body impedance was better correlated with TBW than the impedance index of arm or leg impedance, even after corrections for body build parameters. The study shows that ethnic-specific bias of impedance-based prediction formulas for body composition is due mainly to differences in body build among the ethnic groups. This means that the use of 'general' prediction equations across different (ethnic) population groups without prior testing of their validity should be avoided. Total body impedance has higher predictive value than segmental impedance.

An approach to analyzing the intensity of the daytime surface urban heat island effect at a local scale.

PubMed

Xu, Shenlai

2009-04-01

A landscape index LI is proposed to evaluate the intensity of the daytime surface urban heat island (SUHI) effect at a local scale. Three aspects of this landscape index are crucial: the source landscape, the sink landscape, and the contribution of source and sink landscapes to the intensity of the SUHI. Source and sink landscape types are identified using the thermo-band of Landsat 7 with a spatial resolution of 60 m, along with appropriate threshold values for the Normalized Difference Vegetation Index, Modified Normalized Difference Water Index, and Normalized Difference Built-up Index. The landscape index was defined as the ratio of the contributions of the source and sink landscapes to the intensity of the SUHI. The intensity of the daytime SUHI is assessed with the help of the landscape index. Our analysis indicates the landscape index can be used to evaluate and compare the intensity of the daytime SUHI for different areas.

Fortification of seaweed (Eucheuma cottonii) flour on nutrition, iodine, and glycemic index of pasta

NASA Astrophysics Data System (ADS)

Firdaus, Muhamad; Yahya; Raditya Hardany Nugraha, Galih; Dwi Utari, Dyah

2017-10-01

Pasta is a nutritious and energy product which produced from the dough of wheat flour and water. It contains less of iodine and high of glycemic index. Euchema cottonii belongs of red seaweed is food substance that contains much of iodine and dietary fiber. The objective of this study was to know the fortification effect of E. cottonii flour on the nutrition, iodine, and glycemic index of pasta. E. cottonii was collected from the culture farm of E. cottonii on the Wongsorejo beach, District of Banyuwangi, East Java on April-June 2015. Wheat flour and pasta ingredients were obtained locally at shops of Pasar Besar, Malang. Pasta was produced by weighing of components, mixing, dough, milling, steaming and drying. E. cottonii flour was added on mixing process at 0; 7; 14 and 21 % of ingredients. The parameter of this study was the level of water, lipid, protein, ash, and carbohydrate (by difference), iodine, crude fiber, the total of dietary fiber, soluble fiber, insoluble fiber, and glycemic index, respectively. Data were analyzed by variance and the least square difference used to determine the difference between treatments. The highest concentration group showed more nutritious than other treatments. The characters of its product were water 6.70%, lipid 2.26%, protein 23.09%, ash 14.11%, carbohydrate 53.84%, iodine 3.71 ppm, crude fiber 8.02%, the total of dietary fiber 20.88%, soluble fiber 11.69%, insoluble fiber 9.19%, and glycemic index 44.45, respectively. In conclusion, the fortification of E. cottonii flour enhances the nutrition value, iodine content, and glycemic index of pasta.

Use of a macroinvertebrate based biotic index to estimate critical metal concentrations for good ecological water quality.

PubMed

Van Ael, Evy; De Cooman, Ward; Blust, Ronny; Bervoets, Lieven

2015-01-01

Large datasets from total and dissolved metal concentrations in Flemish (Belgium) fresh water systems and the associated macroinvertebrate-based biotic index MMIF (Multimetric Macroinvertebrate Index Flanders) were used to estimate critical metal concentrations for good ecological water quality, as imposed by the European Water Framework Directive (2000). The contribution of different stressors (metals and water characteristics) to the MMIF were studied by constructing generalized linear mixed effect models. Comparison between estimated critical concentrations and the European and Flemish EQS, shows that the EQS for As, Cd, Cu and Zn seem to be sufficient to reach a good ecological quality status as expressed by the invertebrate-based biotic index. In contrast, the EQS for Cr, Hg and Pb are higher than the estimated critical concentrations, which suggests that when environmental concentrations are at the same level as the EQS a good quality status might not be reached. The construction of mixed models that included metal concentrations in their structure did not lead to a significant outcome. However, mixed models showed the primary importance of water characteristics (oxygen level, temperature, ammonium concentration and conductivity) for the MMIF. Copyright © 2014 Elsevier Ltd. All rights reserved.

Determination of immersion factors for radiance sensors in marine and inland waters: a semi-analytical approach using refractive index approximation

NASA Astrophysics Data System (ADS)

Dev, Pravin J.; Shanmugam, P.

2016-05-01

Underwater radiometers are generally calibrated in air using a standard source. The immersion factors are required for these radiometers to account for the change in the in-water measurements with respect to in-air due to the different refractive index of the medium. The immersion factors previously determined for RAMSES series of commercial radiometers manufactured by TriOS are applicable to clear oceanic waters. In typical inland and turbid productive coastal waters, these experimentally determined immersion factors yield significantly large errors in water-leaving radiances (Lw) and hence remote sensing reflectances (Rrs). To overcome this limitation, a semi-analytical method with based on the refractive index approximation is proposed in this study, with the aim of obtaining reliable Lw and Rrs from RAMSES radiometers for turbid and productive waters within coastal and inland water environments. We also briefly show the variation of pure water immersion factors (Ifw) and newly derived If on Lw and Rrs for clear and turbid waters. The remnant problems other than the immersion factor coefficients such as transmission, air-water and water-air Fresnel's reflectances are also discussed.

A GIS-based Model for Urban Change and Implications for Water Quality in the Pontchartrain Basin

NASA Astrophysics Data System (ADS)

Carstens, D.; Amer, R. M.

2017-12-01

The combination of remote sensing techniques and Geographic Information Systems (GIS) to measure water quality allows researchers to monitor changes in various water quality parameters over temporal and spatial scales that are not always readily apparent from in situ measurements. Water has a distinct spectral behavior in comparison to soil, vegetation and urban, and therefore can be distinguished from surrounding environments. This study involves using remote sensing and GIS methods to map urban sprawl and its resulting influences on water quality in the Pontchartrain Basin over the last three decades. Two images of Landsat Thematic Mapper (TM) were taken in October 1985 and two images of Landsat Operational Land Imager (OLI) were taken in 2015 were atmospherically corrected and processed to map urban sprawl and influences on water quality of Pontchartrain Basin in the last three decades. To accomplish this, a normalized difference building index (NDBI) was developed for Landsat images. The NDBI was calculated from (NIR - SWIR) / (NIR + SWIR), where SWIR is the longest wavelength. The normalized difference vegetation index (NDVI), the normalized difference soil index (NDSI), and the normalized difference water index (NDWI) were also calculated for Landsat images. A GIS model was developed by integrating the NDBI, NDVI, NDSI, and NDWI, and yielded urban/non-urban/water boundary maps with 30-m resolution. Results indicate that urban areas have increased approximately from 25,643 km2 to 26,677 km2, which represents about 4.0% change from non-urban to urban in the last 3 decades. The results are in a good agreement with the U.S. Census data, which indicated that there is a 12.25% increase in population over the last 25 years in the 16 parishes of the Pontchartrain Basin. Urban changes were compared with changes of water quality parameters in PONTCHARTRAIN BASIN, which include pH, specific conductance, nitrogen, phosphorous, and dissolved oxygen. The results show that decrease in dissolved oxygen and phosphorus, and the increase in specific conductance, nitrogen and pH from 1985 to 2015 are consistent with the rate of urban sprawl that occurred during this time period. Future work will include analysis of changes in agricultural and industrial activities and correlation with changes of water quality parameters.

Use of the landfill water pollution index (LWPI) for groundwater quality assessment near the landfill sites.

PubMed

Talalaj, Izabela A; Biedka, Pawel

2016-12-01

The purpose of the paper is to assess the groundwater quality near the landfill sites using landfill water pollution index (LWPI). In order to investigate the scale of groundwater contamination, three landfills (E, H and S) in different stages of their operation were taken into analysis. Samples of groundwater in the vicinity of studied landfills were collected four times each year in the period from 2004 to 2014. A total of over 300 groundwater samples were analysed for pH, EC, PAH, TOC, Cr, Hg, Zn, Pb, Cd, Cu, as required by the UE legal acts for landfill monitoring system. The calculated values of the LWPI allowed the quantification of the overall water quality near the landfill sites. The obtained results indicated that the most negative impact on groundwater quality is observed near the old Landfill H. Improper location of piezometer at the Landfill S favoured infiltration of run-off from road pavement into the soil-water environment. Deep deposition of the groundwater level at Landfill S area reduced the landfill impact on the water quality. Conducted analyses revealed that the LWPI can be used for evaluation of water pollution near a landfill, for assessment of the variability of water pollution with time and for comparison of water quality from different piezometers, landfills or time periods. The applied WQI (Water Quality Index) can also be an important information tool for landfill policy makers and the public about the groundwater pollution threat from landfill.

Determining the impact of urban components on land surface temperature of Istanbul by using remote sensing indices.

PubMed

Bektaş Balçik, Filiz

2014-02-01

For the past 60 years, Istanbul has been experiencing an accelerated urban expansion. This urban expansion is leading to the replacement of natural surfaces by various artificial materials. This situation has a critical impact on the environment due to the alteration of heat energy balance. In this study, the effect upon the urban heat island (UHI) of Istanbul was analyzed using 2009 dated Landsat 5 Thematic Mapper (TM) data. An Index Based Built-up Index (IBI) was used to derive artificial surfaces in the study area. To produce the IBI index, Soil-Adjusted Vegetation Index, Normalized Difference Built-up Index, and Modified Normalized Difference Water Index were calculated. Land surface temperature (LST) distribution was derived from Landsat 5 TM images using a mono-window algorithm. In addition, 24 transects were selected, and different regression models were applied to explore the correlation between LST and IBI index. The results show that artificial surfaces have a positive exponential relationship with LST rather than a simple linear one. An ecological evaluation index of the region was calculated to explore the impact of both the vegetated land and the artificial surfaces on the UHI. Therefore, the quantitative relationship of urban components (artificial surfaces, vegetation, and water) and LST was examined using multivariate statistical analysis, and the correlation coefficient was obtained as 0.829. This suggested that the areas with a high rate of urbanization will accelerate the rise of LST and UHI in Istanbul.

Trawl-based assessment of Lake Ontario pelagic prey fishes including Alewife and Rainbow Smelt

USGS Publications Warehouse

Weidel, Brian C.; Walsh, Maureen; Connerton, Michael J.; Holden, Jeremy P.

2017-01-01

Managing Lake Ontario fisheries in an ecosystem-context, requires reliable data on the status and trends of prey fishes that support predator populations. We report on the community and population dynamics of Lake Ontario pelagic prey fishes, based on bottom trawl surveys. We emphasize information that supports the international Lake Ontario Committee’s Fish Community Objectives. In 2016, 142 bottom trawls were collected in U.S. waters, and for the first time 46 trawls were conducted in Canadian waters. A total of 420,386 fish from 24 species were captured. Alewife were 89% of the total fish catch and 93% of the pelagic prey fish catch. The Rainbow Smelt abundance index in U.S. waters increased slightly in 2016 relative to 2015. Interestingly, the Rainbow Smelt abundance index from tows in Canadian waters was 35% higher than the U.S. index. Abundances of Threespine Stickleback and Emerald Shiners in both U.S. and Canadian waters were low in 2016 relative to their peak abundances in the late 1990s, but Cisco abundance indices suggest a recent increase in their abundance. This year, the reported Alewife abundance time series was truncated to only include values since 1997, which were collected with the same trawl and eliminated the need to adjust values for different trawls. The 2016 adult Alewife abundance index was the second lowest abundance ever observed in the time series. This value was expected to decline from the 2015 value since the indices of juvenile Alewife were low in 2014 and the lowest ever observed in 2015. The fall condition index of adult Alewife increased in 2016 and is consistent with lower abundance and reduced competition for zooplankton resources. The 2016 Age-1 Alewife index increased relative to 2014 and 2015, and suggested lake conditions were favorable for Age-1 survival and growth during the summer of 2015 and the 2015-2016 winter. Interestingly, the catch of adult and Age1 Alewife was higher in trawls conducted in Canadian waters relative to U. S. waters. The larger trawl catches in Canadian waters suggest there may be important spatial differences in lake-wide distribution of prey fishes in April when trawling is conducted. Future surveys should to continue to sample at the whole-lake scale to understand the year to year variability in spatial distribution and the physical or biotic factors driving those distribution differences.

Atmospheric effects on the NDVI - Strategies for its removal. [Normalized Difference Vegetation Index

NASA Technical Reports Server (NTRS)

Kaufman, Y. J.; Tanre, D.; Holben, B. N.; Markham, B.; Gitelson, A.

1992-01-01

The compositing technique used to derive global vegetation index (NDVI) from the NOAA AVHRR radiances reduces the residual effect of water vapor and aerosol on the NDVI. The reduction in the atmospheric effect is shown using a comprehensive measured data set for desert conditions, and a simulation for grass with continental aerosol. A statistical analaysis of the probability of occurrence of aerosol optical thickness and precipitable water vapor measured in different climatic regimes is used for this simulation. It is concluded that for a long compositing period (e.g., 27 days), the residual aerosol optical thickness and precipitable water vapor are usually too small to be corrected. For a 9-day compositing, the residual average aerosol effect may be about twice the correction uncertainty. For Landsat TM or Earth Observing System Moderate Resolution Imaging Spectrometer (EOS-MODIS) data, the newly defined atmospherically resistant vegetation index (ARVI) is more promising than possible direct atmospheric correction schemes, except for heavy desert dust conditions.

Detection of changes in leaf water content using near- and middle-infrared reflectances

NASA Technical Reports Server (NTRS)

Hunt, E. Raymond, Jr.; Rock, Barrett N.

1989-01-01

A method to detect plant water stress by remote sensing is proposed using indices of near-IR and mid-IR wavelengths. The ability of the Leaf Water Content Index (LWCI) to determine leaf relative water content (RWC) is tested on species with different leaf morphologies. The way in which the Misture Stress Index (MSI) varies with RWC is studied. On test with several species, it is found that LWCI is equal to RWC, although the reflectances at 1.6 microns for two different RWC must be known to accurately predict unknown RWC. A linear correlation is found between MSI and RWC with each species having a different regression equation. Also, MSI is correlated with log sub 10 Equivalent Water Thickness (EWT) with data for all species falling on the same regression line. It is found that the minimum significant change of RWC that could be detected by appying the linear regression equation of MSI to EWT is 52 percent. Because the natural RWC variation from water stress is about 20 percent for most species, it is concluded that the near-IR and mid-IR reflectances cannot be used to remotely sense water stress.

Impact of Yangtze River Water Transfer on the Water Quality of the Lixia River Watershed, China

PubMed Central

Ma, Xiaoxue; Wang, Lachun; Wu, Hao; Li, Na; Ma, Lei; Zeng, Chunfen; Zhou, Yi; Yang, Jun

2015-01-01

To improve water quality and reduce the negative impacts of sudden inputs of water pollution in the Lixia River watershed, China, a series of experimental water transfers from the Yangtze River to the Lixia River were conducted from 2 December 2006 to 7 January 2007. Water samples were collected every six days at 55 monitoring sites during this period. Eight water parameters (water temperature, pH, dissolved oxygen (DO), chemical oxygen demand (COD), potassium permanganate index (CODMn), ammonia nitrogen (NH4 +-N), electrical conductivity (EC), and water transparency (WT)) were analyzed to determine changes in nutrient concentrations during water transfers. The comprehensive pollution index (Pi) and single-factor (Si) evaluation methods were applied to evaluate spatio-temporal patterns of water quality during water transfers. Water quality parameters displayed different spatial and temporal distribution patterns within the watershed. Water quality was improved significantly by the water transfers, especially for sites closer to water intake points. The degree of improvement is positively related to rates of transfer inflow and drainage outflow. The effects differed for different water quality parameters at each site and at different water transfer times. There were notable decreases in NH4 +-N, DO, COD, and CODMn across the entire watershed. However, positive effects on EC and pH were not observed. It is concluded that freshwater transfers from the Yangtze River can be used as an emergency measure to flush pollutants from the Lixia River watershed. Improved understanding of the effects of water transfers on water quality can help the development and implementation of effective strategies to improve water quality within this watershed. PMID:25835525

A coupled melt-freeze temperature index approach in a one-layer model to predict bulk volumetric liquid water content dynamics in snow

NASA Astrophysics Data System (ADS)

Avanzi, Francesco; Yamaguchi, Satoru; Hirashima, Hiroyuki; De Michele, Carlo

2016-04-01

Liquid water in snow rules runoff dynamics and wet snow avalanches release. Moreover, it affects snow viscosity and snow albedo. As a result, measuring and modeling liquid water dynamics in snow have important implications for many scientific applications. However, measurements are usually challenging, while modeling is difficult due to an overlap of mechanical, thermal and hydraulic processes. Here, we evaluate the use of a simple one-layer one-dimensional model to predict hourly time-series of bulk volumetric liquid water content in seasonal snow. The model considers both a simple temperature-index approach (melt only) and a coupled melt-freeze temperature-index approach that is able to reconstruct melt-freeze dynamics. Performance of this approach is evaluated at three sites in Japan. These sites (Nagaoka, Shinjo and Sapporo) present multi-year time-series of snow and meteorological data, vertical profiles of snow physical properties and snow melt lysimeters data. These data-sets are an interesting opportunity to test this application in different climatic conditions, as sites span a wide latitudinal range and are subjected to different snow conditions during the season. When melt-freeze dynamics are included in the model, results show that median absolute differences between observations and predictions of bulk volumetric liquid water content are consistently lower than 1 vol%. Moreover, the model is able to predict an observed dry condition of the snowpack in 80% of observed cases at a non-calibration site, where parameters from calibration sites are transferred. Overall, the analysis show that a coupled melt-freeze temperature-index approach may be a valid solution to predict average wetness conditions of a snow cover at local scale.

Modeling the Soil Water and Energy Balance of a Mixed Grass Rangeland and Evaluating a Soil Water Based Drought Index in Wyoming

NASA Astrophysics Data System (ADS)

Engda, T. A.; Kelleners, T. J.; Paige, G. B.

2013-12-01

Soil water content plays an important role in the complex interaction between terrestrial ecosystems and the atmosphere. Automated soil water content sensing is increasingly being used to assess agricultural drought conditions. A one-dimensional vertical model that calculates incoming solar radiation, canopy energy balance, surface energy balance, snow pack dynamics, soil water flow, snow-soil heat exchange is applied to calculate water flow and heat transport in a Rangeland soil located near Lingel, Wyoming. The model is calibrated and validated using three years of measured soil water content data. Long-term average soil water content dynamics are calculated using a 30 year historical data record. The difference between long-term average soil water content and observed soil water content is compared with plant biomass to evaluate the usefulness of soil water content as a drought indicator. Strong correlation between soil moisture surplus/deficit and plant biomass may prove our hypothesis that soil water content is a good indicator of drought conditions. Soil moisture based drought index is calculated using modeled and measured soil water data input and is compared with measured plant biomass data. A drought index that captures local drought conditions proves the importance of a soil water monitoring network for Wyoming Rangelands to fill the gap between large scale drought indices, which are not detailed enough to assess conditions at local level, and local drought conditions. Results from a combined soil moisture monitoring and computer modeling, and soil water based drought index soil are presented to quantify vertical soil water flow, heat transport, historical soil water variations and drought conditions in the study area.

Selection of an evaluation index for water ecological civilizations of water-shortage cities based on the grey rough set

NASA Astrophysics Data System (ADS)

Zhang, X. Y.; Zhu, J. W.; Xie, J. C.; Liu, J. L.; Jiang, R. G.

2017-08-01

According to the characteristics and existing problems of water ecological civilization of water-shortage cities, the evaluation index system of water ecological civilization was established using a grey rough set. From six aspects of water resources, water security, water environment, water ecology, water culture and water management, this study established the prime frame of the evaluation system, including 28 items, and used rough set theory to undertake optimal selection of the index system. Grey correlation theory then was used for weightings in order that the integrated evaluation index system for water ecology civilization of water-shortage cities could be constituted. Xi’an City was taken as an example, for which the results showed that 20 evaluation indexes could be obtained after optimal selection of the preliminary framework of evaluation index. The most influential indices were the water-resource category index and water environment category index. The leakage rate of the public water supply pipe network, as well as the disposal, treatment and usage rate of polluted water, urban water surface area ratio, the water quality of the main rivers, and so on also are important. It was demonstrated that the evaluation index could provide an objectively reflection of regional features and key points for the development of water ecology civilization for cities with scarce water resources. It is considered that the application example has universal applicability.

A global analysis of the environmental cost of river water withdrawals

NASA Astrophysics Data System (ADS)

Soligno, Irene; Ridolfi, Luca; Laio, Francesco

2017-04-01

World freshwater ecosystems are considerably declining, at a faster rate than other ecosystems. Water withdrawals are identified as one of the main drivers of increasing water stress in several river basins worldwide. So far, much effort has been devoted to quantify water withdrawals and fluvial water consumptions at a global scale; however, comparisons are not simple because the irregular spatiotemporal distribution of freshwater resources entails that the same volume of consumed water does not have the same environmental "cost" in different times or places. In order to take into account this spatial and temporal heterogeneity, our work proposes a novel index to evaluate the environmental cost of a reference amount of water withdrawn from a generic river section. The index depends on (i) the local environmental relevance of the impacted fluvial ecosystem (e.g., nutrient/sediment transport capacity, width of the riparian region, biodiversity richness) and (ii) the portion of the river network impacted by the reference water withdrawal, that is the downstream drainage network. In the present work, the index is applied at a global scale with a 0.5° x 0.5° spatial resolution and employing annual average data of river discharge. Globally, regions and countries more environmentally vulnerable to water depletion are identified. Since the proposed index systematically assesses the environmental cost by accounting for the downstream propagation effect of a water withdrawal on the fluvial ecosystem, it aims to support decision-making in global transboundary river basins as well.

Spectral entropy as a mean to quantify water stress history for natural vegetation and irrigated agriculture in a water-stressed tropical environment

NASA Astrophysics Data System (ADS)

Kim, Y.; Johnson, M. S.

2017-12-01

Spectral entropy (Hs) is an index which can be used to measure the structural complexity of time series data. When a time series is made up of one periodic function, the Hs value becomes smaller, while Hs becomes larger when a time series is composed of several periodic functions. We hypothesized that this characteristic of the Hs could be used to quantify the water stress history of vegetation. For the ideal condition for which sufficient water is supplied to an agricultural crop or natural vegetation, there should be a single distinct phenological cycle represented in a vegetation index time series (e.g., NDVI and EVI). However, time series data for a vegetation area that repeatedly experiences water stress may include several fluctuations that can be observed in addition to the predominant phenological cycle. This is because the process of experiencing water stress and recovering from it generates small fluctuations in phenological characteristics. Consequently, the value of Hs increases when vegetation experiences several water shortages. Therefore, the Hs could be used as an indicator for water stress history. To test this hypothesis, we analyzed Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data for a natural area in comparison to a nearby sugarcane area in seasonally-dry western Costa Rica. In this presentation we will illustrate the use of spectral entropy to evaluate the vegetative responses of natural vegetation (dry tropical forest) and sugarcane under three different irrigation techniques (center pivot irrigation, drip irrigation and flood irrigation). Through this comparative analysis, the utility of Hs as an indicator will be tested. Furthermore, crop response to the different irrigation methods will be discussed in terms of Hs, NDVI and yield.

Informed community mobilization for dengue prevention in households with and without a regular water supply: Secondary analysis from the Camino Verde trial in Nicaragua.

PubMed

Cárcamo, Alvaro; Arosteguí, Jorge; Coloma, Josefina; Harris, Eva; Ledogar, Robert J; Andersson, Neil

2017-05-30

Studies in different countries have identified irregular water supply as a risk factor for dengue virus transmission. In 2013, Camino Verde, a cluster-randomised controlled trial in Managua, Nicaragua, and Mexico's Guerrero State, demonstrated impact of evidence-based community mobilisation on recent dengue infection and entomological indexes of infestation by Aedes aegypti mosquitoes. This secondary analysis of data from the trial impact survey asks: (1) what is the importance of regular water supply in neighbourhoods with and without the trial intervention and (2) can community interventions like Camino Verde reasonably exclude households with adequate water supply? Entomological data collected in the dry season of 2013 in intervention and control communities allow contrasts between households with regular and irregular water supplies. Indicators of entomological risk included the House Index and pupa positive household index. Generalised linear mixed models with cluster as a random effect compared households with and without regular water, and households in intervention and control communities. For the House Index, regular water supply was associated with a protection in both intervention households (OR 0.7, 95%CI 0.6-0.9) and control households (OR 0.6, 95%CI 0.5-0.8). For the pupa positive household index, we found a similar protection from regular water supply in intervention households (OR 0.6, 95%CI 0.4-0.8) and control households (OR 0.7, 95%CI 0.5-0.9). The Camino Verde intervention had a similar impact on House Index in households with regular water supply (OR 0.7, 95%CI 0.5-1.0) and irregular water supply (OR 0.6, 95%CI 0.4-0.8); for the pupa positive household index, the effect of the intervention was very similar in households with regular (OR0.5, 95%CI 0.3-0.8) and irregular (OR 0.5, 95%CI 0.3-0.9) water supply. While Aedes aegypti control efforts based on informed community mobilisation had a strong impact on households without a regular water supply, this intervention also impacted entomological indices in households with a regular water supply. These households should not be excluded from community mobilisation efforts to reduce the Aedes aegypti vector. ISRCTN27581154 .

Vulnerability of Water Resources under Climate and Land Use Change: Evaluation of Present and Future Threats for Austria

NASA Astrophysics Data System (ADS)

Nachtnebel, Hans-Peter; Wesemann, Johannes; Herrnegger, Mathew; Senoner, Tobias; Schulz, Karsten

2015-04-01

Climate and Land Use Change can have severe impacts on natural water resources needed for domestic, agricultural and industrial water use. In order to develop adaptation strategies, it is necessary to assess the present and future vulnerability of the water resources on the basis of water quantity, water quality and adaptive capacity indicators. Therefore a methodological framework was developed within the CC-Ware project and a detailed assessment was performed for Austria. The Water Exploitation Index (WEI) is introduced as a quantitative indicator. It is defined as the ratio between the water demand and the water availability. Water availability is assessed by a high resolution grid-based water balance model, utilizing the meteorological information from bias corrected regional climate models. The demand term can be divided into domestic, agricultural and industrial water demand and is assessed on the water supply association level. The Integrated Groundwater Pollution Load Index (GWPLI) represents an indicator for areas at risk regarding water quality, considering agricultural loads (nitrate pollution loads), potential erosion and potential risks from landfills. Except for the landfills, the information for the current situation is based on the CORINE Landcover data. Future changes were predicted utilizing the PRELUDE land use scenarios. Since vulnerability is also dependent on the adaptive capacity of a system, the Adaptive Capacity Index is introduced. The Adaptive Capacity Index thereby combines the Ecosystem Service Index (ESSI), which represents three water related ecosystem services (Water Provision, Water Quantity Regulation and Water Quality Regulation) and the regional economic capacity expressed by the gross value added. On the basis of these indices, the Overall Vulnerability of the water resources can be determined for the present and the future. For Austria the different indices were elaborated. Maps indicating areas of different levels of vulnerability were developed. A comparison with existing data (River Basin Management Plan and Groundwater Chemistry Regulation) shows a good agreement between the elaborated maps and observations for the present state. The Overall Vulnerability is very low and low for most parts of Austria, especially in the forested alpine region. Bigger cities like Vienna, Graz and Linz show medium vulnerabilities, due to the high water demand and low ecosystem services. Only in the north-eastern and south-eastern part of the country some water supply associations with high and very high overall vulnerability exist. Groundwater recharge is quite small in these regions and the water quality is limited due to intense agriculture and possible threats through landfills. The developed framework allows an evaluation of water quantity and quality vulnerabilities for large scales for the present and the future. Including ecosystem services and gross value added an overall vulnerability can be determined.

Spatial heterogeneity of water quality in a highly degraded tropical freshwater ecosystem.

PubMed

Zambrano, Luis; Contreras, Victoria; Mazari-Hiriart, Marisa; Zarco-Arista, Alba E

2009-02-01

Awareness of environmental heterogeneity in ecosystems is critical for management and conservation. We used the Xochimilco freshwater system to describe the relationship between heterogeneity and human activities. This tropical aquatic ecosystem south of Mexico City is comprised of a network of interconnected canals and lakes that are influenced by agricultural and urban activities. Environmental heterogeneity was characterized by spatially extensive surveys within four regions of Xochimilco during rainy and dry seasons over 2 years. These surveys revealed a heterogeneous system that was shallow (1.1 m, SD=0.4 ), warm (17 degrees C, SD=2.9), well oxygenated (5.0 mg l(-1), SD=3), turbid (45.7 NTU SD = 26.96), and extremely nutrient-rich (NO(3)-N=15.9 mg l(-1), SD=13.7; NH(4)-N=2.88 mg l(-1), SD=4.24; and PO(4)-P=8.3 mg l(-1), SD=2.4). Most of the variables were not significantly different between years, but did differ between seasons, suggesting a dynamic system within a span of a year but with a high resilience over longer periods of time. Maps were produced using interpolations to describe distributions of all variables. There was no correlation between individual variables and land use. Consequently, we searched for relationships using all variables together by generating a combined water quality index. Significant differences in the index were apparent among the four regions. Index values also differed within individual region and individual water bodies (e.g., within canals), indicating that Xochimilco has high local heterogeneity. Using this index on a map helped to relate water quality to human activities and provides a simple and clear tool for managers and policymakers.

Spatial Heterogeneity of Water Quality in a Highly Degraded Tropical Freshwater Ecosystem

NASA Astrophysics Data System (ADS)

Zambrano, Luis; Contreras, Victoria; Mazari-Hiriart, Marisa; Zarco-Arista, Alba E.

2009-02-01

Awareness of environmental heterogeneity in ecosystems is critical for management and conservation. We used the Xochimilco freshwater system to describe the relationship between heterogeneity and human activities. This tropical aquatic ecosystem south of Mexico City is comprised of a network of interconnected canals and lakes that are influenced by agricultural and urban activities. Environmental heterogeneity was characterized by spatially extensive surveys within four regions of Xochimilco during rainy and dry seasons over 2 years. These surveys revealed a heterogeneous system that was shallow (1.1 m, SD = 0.4 ), warm (17°C, SD = 2.9), well oxygenated (5.0 mg l-1, SD = 3), turbid (45.7 NTU SD = 26.96), and extremely nutrient-rich (NO3-N = 15.9 mg l-1, SD=13.7; NH4-N = 2.88 mg l-1, SD = 4.24; and PO4-P = 8.3 mg l-1, SD = 2.4). Most of the variables were not significantly different between years, but did differ between seasons, suggesting a dynamic system within a span of a year but with a high resilience over longer periods of time. Maps were produced using interpolations to describe distributions of all variables. There was no correlation between individual variables and land use. Consequently, we searched for relationships using all variables together by generating a combined water quality index. Significant differences in the index were apparent among the four regions. Index values also differed within individual region and individual water bodies (e.g., within canals), indicating that Xochimilco has high local heterogeneity. Using this index on a map helped to relate water quality to human activities and provides a simple and clear tool for managers and policymakers.

The optical properties of regenerated silk fibroin films obtained from different sources

NASA Astrophysics Data System (ADS)

Perotto, Giovanni; Zhang, Yuji; Naskar, Deboki; Patel, Nereus; Kaplan, David L.; Kundu, Subhas C.; Omenetto, Fiorenzo G.

2017-09-01

Silk fibroin possesses unique properties for bio-functional optical interfaces and has been attracting increasing interest as an optical material. Here, we report on the refractive index and absorption coefficient of silk fibroin extracted from Bombyx mori, Antheraea mylitta, Samia ricini, and Antheraea assamensis. The influence of protein molecular weight, residual water content, and crystallinity on refractive index was investigated. The parameters for the Cauchy dispersion law and Urbach absorption were determined for each of the silk fibroins. By exploiting the differences in refractive index between the different fibroins, an all-protein slab waveguide was fabricated.

An innovative index for evaluating water quality in streams.

PubMed

Said, Ahmend; Stevens, David K; Sehlke, Gerald

2004-09-01

A water quality index expressed as a single number is developed to describe overall water quality conditions using multiple water quality variables. The index consists of water quality variables: dissolved oxygen, specific conductivity, turbidity, total phosphorus, and fecal coliform. The objectives of this study were to describe the preexisting indices and to define a new water quality index that has advantages over these indices. The new index was applied to the Big Lost River Watershed in Idaho, and the results gave a quantitative picture for the water quality situation. If the new water quality index for the impaired water is less than a certain number, remediation-likely in the form of total maximum daily loads or changing the management practices-may be needed. The index can be used to assess water quality for general beneficial uses. Nevertheless, the index cannot be used in making regulatory decisions, indicate water quality for specific beneficial uses, or indicate contamination from trace metals, organic contaminants, and toxic substances.

Evaluation of water quality at the source of streams of the Sinos River Basin, southern Brazil.

PubMed

Benvenuti, T; Kieling-Rubio, M A; Klauck, C R; Rodrigues, M A S

2015-05-01

The Sinos River Basin (SRB) is located in the northeastern region of the state of Rio Grande do Sul (29º20' to 30º10'S and 50º15' to 51º20'W), southern Brazil, and covers two geomorphologic provinces: the southern plateau and the central depression. It is part of the Guaíba basin, has an area of approximately 800 km 2 and contains 32 counties. The basin provides drinking water for 1.6 million inhabitants in one of the most important industrial centres in Brazil. This study describes different water quality indices (WQI) used for the sub-basins of three important streams in the SRB: Pampa, Estância Velha/Portão and Schmidt streams. Physical, chemical and microbiological parameters assessed bimonthly using samples collected at each stream source were used to calculate the Horton Index (HI), the Dinius Index (DI) and the water quality index adopted by the US National Sanitation Foundation (NSF WQI) in the additive and multiplicative forms. These indices describe mean water quality levels at the streams sources. The results obtained for these 3 indexes showed a worrying scenario in which water quality has already been negatively affected at the sites where three important sub-basins in the Sinos River Basin begin to form.

What is the Optimal Water Productivity Index for Irrigated Grapevines? Case of 'Godello' and 'Albariño' cultivars

NASA Astrophysics Data System (ADS)

Fandiño, María; Martínez, Emma M.; Rey, Benjamín J.; Cancela, Javier J.

2015-04-01

Different studies have tackled the conceptual and terminological study of crop water use indicators, mainly water use efficiency (WUE) and water productivity (WP) (Pereira et al., 2012; Scheierling et al., 2014). The high number of stakeholders, working about agricultural water use (hydrology and hydrogeology, civil and irrigation engineering, agronomy and crop physiology, economics), has hindered the real improvement thereof, from a multidisciplinary perspective. For example, Flexas et al. (2010) reviewed the future improvements in water use efficiency in grapevines, from a physiological approach. In this study, two grapevine cultivars, priority in Galicia (Spain): 'Godello' (DO Valdeorras) and 'Albariño' (DO Rías Baixas, two locations), was assessed in relation to four water productivity index, focus on irrigation systems, agronomy and crop physiology aspects, during a wet year (2012). All WP index was referred to farm yield level (kg ha-1); where the denominator applied to WPTWU, include all components of soil water balance; to WPTWUfarm, introduced rainfall and irrigation depth; to WPIrrig, only irrigation depth applied; and to WPT, crop transpiration was used. In the last index, SIMDualKc model was used to partitioning crop evapotranspiration and cover crop transpiration. Different ranges of values was obtained for both cultivars, WPTWUfarm was higher in cv 'Godello' than in cv 'Albariño', 3.8 and 0.9 kg m-3 respectively. Average value to WPIrrig has showed: 17.6 kg m-3 for cv 'Albariño' and 15.5 kg m-3 for cv 'Godello', due to a reduction of 60% of irrigation depth in DO Rías Baixas. However, for both locations, higher WPIrrig was obtained to drip irrigation system versus subsurface drip irrigation. WPT showed a different tendency, rain-fed 'Godello' and surface drip irrigation 'Albariño' treatments obtained higher values (6.8 and 3.6 kg m-3), with higher WPT to cv 'Godello' for all treatments versus 'Albariño'. Results had showed that water productivity indexes are cultivar depending, similar values was achieved in near locations (data not showed). Special care must be taken when analysing water productivity indexes at the farm level, considering identical irrigation depth, density, canopy management system, age of the plantation, management practices, among other factors, which may affect of water consumed or supplied to the vineyard. Agronomical economic aspects should be studied, taken into account irrigation systems cost and benefit crop yield, at basin scale. Temperate viticulture should pursue greater WUE and WP, identifying the most productive cultivars adapted to near-future climate conditions. References: Flexas J, Galmés J, Gallé A, Gulías J, Pou A, Ribas-Carbo M, Tomàs M, Medrano H (2010). Improving water use efficiency in grapevines: potential physiological targets for biotechnological improvement. Australian Journal of Grape and Wine Research, 16(s1):106-121 Pereira LS, Cordery I, Iacovides I (2012). Improved indicators of water use performance and productivity for sustainable water conservation and saving. Agricultural Water Management, 108:39-51 Scheierling SM, Treguer DO, Booker JF, Decker E (2014). How to assess agricultural water productivity? looking for water in the agricultural productivity and efficiency literature. Looking for Water in the Agricultural Productivity and Efficiency Literature (July 1, 2014). World Bank Policy Research Working Paper, (6982)

[Study on method and its optimization of improving seed germination of Astragalus membranaceus as gansu traditional medicinal herb].

PubMed

Shi, Li-Ping; Ou, Qiao-Ming; Cui, Wen-Juan; Chen, Yu-Liang

2014-04-01

To break the hard testa and improve seed germination situation of Astragalus membranaceus var. mongholicus, in order to solve the problems of low success rate of seed germination and seedling. Longxi Astragalus membranaceus var. mongholicus seed was treated by soaking seed with 75% alcohol and concentrated sulfuric acid, warm-water incubating, grinding and comprehensive treating with warm-water incubating, grinding and sand culture. Its seed germination situation was evaluated by germination potential, germination rate and germination index. Different processing methods significantly improved seed germination with different effect. Comprehensive treatment with warm-water incubating, grinding and sand culture was the best one on Astragalus membranaceus var. mongholicus seed germination. Its germination potential, germination rate and germination index was 66.04%, 87.70% and 1.34,respectively. Comprehensive treatment with warm-water incubating, grinding and sand culture is an economic and effective processing method, which is suitable for actual production.

Estimating maize water stress by standard deviation of canopy temperature in thermal imagery

USDA-ARS?s Scientific Manuscript database

A new crop water stress index using standard deviation of canopy temperature as an input was developed to monitor crop water status. In this study, thermal imagery was taken from maize under various levels of deficit irrigation treatments in different crop growing stages. The Expectation-Maximizatio...

Effect of feed composition, moisture content and extrusion temperature on extrudate characteristics of yam-corn-rice based snack food.

PubMed

Seth, Dibyakanta; Badwaik, Laxmikant S; Ganapathy, Vijayalakshmi

2015-03-01

Blends of yam, rice and corn flour were processed in a twin-screw extruder. Effects of yam flour (10-40 %), feed moisture content (12-24 %) and extruder barrel temperature (100-140 °C) on the characteristics of the dried extrudates was investigated using a statistical technique response surface methodology (RSM). Radial expansion ratio differed significantly (p ≤ 0.05) with change in all the independent variables. Highest expansion (3.97) was found at lowest moisture content (12 %) and highest barrel temperature (140 °C). Increased yam flour level decreased the expansion ratio significantly. Water absorption index (WAI) increased significantly with increase of all variables. However, water solubility index (WSI) did not change with change in yam flour percent. Hardness of extrudates that varied from 3.86 to 6.94 N was positively correlated with yam flour level and feed moisture content, however it decreased significantly (p ≤ 0.001) with increase of barrel temperature. Yam percent of 15.75 with feed moisture and barrel temperature at 12.00 % and 140 °C respectively gave an optimized product of high desirability (> 0.90) with optimum responses of 3.29 expansion ratio, 5.64 g/g dry solid water absorption index, 30.39 % water solubility index and 3.86 N hardness. The predicted values registered non-significant (p < 0.10) differences from the experimental results. Further study would include the sensory properties enhancement of extruded snacks and little emphasis on the chemistry of interaction between different components.

Utilization of combined remote sensing techniques to detect environmental variables influencing malaria vector densities in rural West Africa

PubMed Central

2012-01-01

Introduction The use of remote sensing has found its way into the field of epidemiology within the last decades. With the increased sensor resolution of recent and future satellites new possibilities emerge for high resolution risk modeling and risk mapping. Methods A SPOT 5 satellite image, taken during the rainy season 2009 was used for calculating indices by combining the image's spectral bands. Besides the widely used Normalized Difference Vegetation Index (NDVI) other indices were tested for significant correlation against field observations. Multiple steps, including the detection of surface water, its breeding appropriateness for Anopheles and modeling of vector imagines abundance, were performed. Data collection on larvae, adult vectors and geographic parameters in the field, was amended by using remote sensing techniques to gather data on altitude (Digital Elevation Model = DEM), precipitation (Tropical Rainfall Measurement Mission = TRMM), land surface temperatures (LST). Results The DEM derived altitude as well as indices calculations combining the satellite's spectral bands (NDTI = Normalized Difference Turbidity Index, NDWI Mac Feeters = Normalized Difference Water Index) turned out to be reliable indicators for surface water in the local geographic setting. While Anopheles larvae abundance in habitats is driven by multiple, interconnected factors - amongst which the NDVI - and precipitation events, the presence of vector imagines was found to be correlated negatively to remotely sensed LST and positively to the cumulated amount of rainfall in the preceding 15 days and to the Normalized Difference Pond Index (NDPI) within the 500 m buffer zone around capture points. Conclusions Remotely sensed geographical and meteorological factors, including precipitations, temperature, as well as vegetation, humidity and land cover indicators could be used as explanatory variables for surface water presence, larval development and imagines densities. This modeling approach based on remotely sensed information is potentially useful for counter measures that are putting on at the environmental side, namely vector larvae control via larviciding and water body reforming. PMID:22443452

Utilization of combined remote sensing techniques to detect environmental variables influencing malaria vector densities in rural West Africa.

PubMed

Dambach, Peter; Machault, Vanessa; Lacaux, Jean-Pierre; Vignolles, Cécile; Sié, Ali; Sauerborn, Rainer

2012-03-23

The use of remote sensing has found its way into the field of epidemiology within the last decades. With the increased sensor resolution of recent and future satellites new possibilities emerge for high resolution risk modeling and risk mapping. A SPOT 5 satellite image, taken during the rainy season 2009 was used for calculating indices by combining the image's spectral bands. Besides the widely used Normalized Difference Vegetation Index (NDVI) other indices were tested for significant correlation against field observations. Multiple steps, including the detection of surface water, its breeding appropriateness for Anopheles and modeling of vector imagines abundance, were performed. Data collection on larvae, adult vectors and geographic parameters in the field, was amended by using remote sensing techniques to gather data on altitude (Digital Elevation Model = DEM), precipitation (Tropical Rainfall Measurement Mission = TRMM), land surface temperatures (LST). The DEM derived altitude as well as indices calculations combining the satellite's spectral bands (NDTI = Normalized Difference Turbidity Index, NDWI Mac Feeters = Normalized Difference Water Index) turned out to be reliable indicators for surface water in the local geographic setting. While Anopheles larvae abundance in habitats is driven by multiple, interconnected factors - amongst which the NDVI - and precipitation events, the presence of vector imagines was found to be correlated negatively to remotely sensed LST and positively to the cumulated amount of rainfall in the preceding 15 days and to the Normalized Difference Pond Index (NDPI) within the 500 m buffer zone around capture points. Remotely sensed geographical and meteorological factors, including precipitations, temperature, as well as vegetation, humidity and land cover indicators could be used as explanatory variables for surface water presence, larval development and imagines densities. This modeling approach based on remotely sensed information is potentially useful for counter measures that are putting on at the environmental side, namely vector larvae control via larviciding and water body reforming. © 2012 Dambach et al; licensee BioMed Central Ltd.

Evaluating multiple indices of agricultural water use efficiency and productivity to improve comparisons between sites and trends

NASA Astrophysics Data System (ADS)

Levy, M. C.

2012-12-01

Approximately 70% of global available freshwater supplies are used in the agricultural sector. Increased demands for water to meet growing population food requirements, and expected changes in the reliability of freshwater supplies due to climate change, threaten the sustainability of water supplies worldwide - not only on farms, but in connected cities and industries. Researchers concerned with agricultural water use sustainability use a variety of theoretical and empirical measures of efficiency and productivity to gain insight into the sustainability of agricultural water use. However, definitions of measures, or indices, vary between different natural and political boundaries, across regions, states and nations and between their respective research, industry, and environmental groups. Index development responds to local data availability and local agendas, and there is debate about the validity of various indices. However, real differences in empirical index measures are not well-understood across the multiple disciplines that study agricultural water use, including engineering and hydrology, agronomy, climate and soil sciences, and economics. Nevertheless reliable, accessible, and generalizable indices are required for planners and policymakers to promote sustainable water use systems. This study synthesizes a set of water use efficiency and productivity indices based on academic, industry and government literature in California and Australia, two locations with similarly water-stressed and valuable agricultural industries under pressure to achieve optimal water use efficiency and productivity. Empirical data at the irrigation district level from the California San Joaquin Valley and Murray Darling Basin states of Victoria and New South Wales in Australia are used to compute indices that estimate efficiency, yield productivity, and economic productivity of agricultural water use. Multiple index estimates of same time-series data demonstrate historical spread in efficiency and productivity measures in different agricultural regions. Individual indices consistently over- or under- estimate trends in efficiency and productivity by their construction, and may provide inaccurate results in years with extreme climatic events, such as droughts. By treating multiple indices as an "ensemble" of measures, analogous to the treatment of multiple climate model predictions, this study quantifies likely "true" states of efficiency and productivity in the selected agricultural regions, and error in individual indices. While different individual indices are preferable at different scales, and relative to the quality of available input data, ensemble indices can be more reliably used in comparative study across different agricultural regions, and for prediction.

A Sensitivity Analysis of NDWI and SRWI to Different types of Vegetation Moisture

NASA Astrophysics Data System (ADS)

Chai, Linna; Chen, Zhizhong

2017-04-01

There are many definitions of vegetation moisture, such as fuel moisture content (FMC), gravimetric water content (GWC), relative water content (RWC), leaf water content (LWC), canopy water content (CWC) and vegetation water content (VWC). They were introduced because of different applications. For example, FMC is with superiority in monitoring wildfire potential, and GWC responses well to determine whether the plant is in health. RWC is suitable for estimating vegetation water stress. LWC and CWC are often used in optical remote sensing and are always related to equivalent water thickness (EWT). For VWC, the main application is for improving retrievals of soil moisture content from microwave sensors. For optical remote sensing technique, the absorption features of liquid water in plant leaves are readily detectable by spectroscopy. Spectral reflectance at 970nm, 1200nm, 1450nm, 1930nm and 2500nm are the basis of numerous remote-sensing indices that could be used in estimating vegetation moisture. Foregoing studies have introduced different spectral indices based on these bands to retrieve vegetation moisture. These spectral indices often fall into two categories, one is Normalized Different Water Index (NDWI), and the other is Simple Ratio Water Index (SRWI). NDWIs take the form of normalized difference spectral index, while SRWIs are in the form of ratio type. They were calculated from different combinations of spectral channels. Since the sensitivities to vegetation moisture of reflectance at different spectral channel are distinguished from each other, the capabilities of these NDWIs and SRWIs in estimating different types of vegetation moisture will be distinguished from one to one. In this work, based on in-situ measurements collected in the north China plain from wheat and corn (Fig. 1), a sensitivity analysis of NDWI and SRWI to different types of vegetation moisture, such as VWC, FMC and GWC, was carried out. They were calculated from different combinations of spectral channels of MODIS and Landsat-8 OLI. Result shows that: 1) NDWI and SRWI are more sensitive to VWC than to FMC and GWC; 2) SRWI and NDWI calculated from reflectances of green band at about 550nm and shortwave infrared band at about 1240nm often yielded relatively higher correlation coefficients with VWC; 3) For a fixed two-band combination, SRWI shows a slight superiority to NDWI. PIC Fig.1 The north China plain and the experimental area with corn and winter wheat sample locations A detailed description to this study work will be demonstrated in the fullpaper.

Impacts of Water Stress on Forest Recovery and Its Interaction with Canopy Height.

PubMed

Xu, Peipei; Zhou, Tao; Yi, Chuixiang; Luo, Hui; Zhao, Xiang; Fang, Wei; Gao, Shan; Liu, Xia

2018-06-13

Global climate change is leading to an increase in the frequency, intensity, and duration of drought events, which can affect the functioning of forest ecosystems. Because human activities such as afforestation and forest attributes such as canopy height may exhibit considerable spatial differences, such differences may alter the recovery paths of drought-impacted forests. To accurately assess how climate affects forest recovery, a quantitative evaluation on the effects of forest attributes and their possible interaction with the intensity of water stress is required. Here, forest recovery following extreme drought events was analyzed for Yunnan Province, southwest China. The variation in the recovery of forests with different water availability and canopy heights was quantitatively assessed at the regional scale by using canopy height data based on light detection and ranging (LiDAR) measurements, enhanced vegetation index data, and standardized precipitation evapotranspiration index (SPEI) data. Our results indicated that forest recovery was affected by water availability and canopy height. Based on the enhanced vegetation index measures, shorter trees were more likely to recover than taller ones after drought. Further analyses demonstrated that the effect of canopy height on recovery rates after drought also depends on water availability—the effect of canopy height on recovery diminished as water availability increased after drought. Additional analyses revealed that when the water availability exceeded a threshold (SPEI > 0.85), no significant difference in the recovery was found between short and tall trees ( p > 0.05). In the context of global climate change, future climate scenarios of RCP2.6 and RCP8.5 showed more frequent water stress in Yunnan by the end of the 21st century. In summary, our results indicated that canopy height casts an important influence on forest recovery and tall trees have greater vulnerability and risk to dieback and mortality from drought. These results may have broad implications for policies and practices of forest management.

Land surface temperature downscaling using random forest regression: primary result and sensitivity analysis

NASA Astrophysics Data System (ADS)

Pan, Xin; Cao, Chen; Yang, Yingbao; Li, Xiaolong; Shan, Liangliang; Zhu, Xi

2018-04-01

The land surface temperature (LST) derived from thermal infrared satellite images is a meaningful variable in many remote sensing applications. However, at present, the spatial resolution of the satellite thermal infrared remote sensing sensor is coarser, which cannot meet the needs. In this study, LST image was downscaled by a random forest model between LST and multiple predictors in an arid region with an oasis-desert ecotone. The proposed downscaling approach was evaluated using LST derived from the MODIS LST product of Zhangye City in Heihe Basin. The primary result of LST downscaling has been shown that the distribution of downscaled LST matched with that of the ecosystem of oasis and desert. By the way of sensitivity analysis, the most sensitive factors to LST downscaling were modified normalized difference water index (MNDWI)/normalized multi-band drought index (NMDI), soil adjusted vegetation index (SAVI)/ shortwave infrared reflectance (SWIR)/normalized difference vegetation index (NDVI), normalized difference building index (NDBI)/SAVI and SWIR/NDBI/MNDWI/NDWI for the region of water, vegetation, building and desert, with LST variation (at most) of 0.20/-0.22 K, 0.92/0.62/0.46 K, 0.28/-0.29 K and 3.87/-1.53/-0.64/-0.25 K in the situation of +/-0.02 predictor perturbances, respectively.

Assessment of Pansharpening Methods Applied to WorldView-2 Imagery Fusion.

PubMed

Li, Hui; Jing, Linhai; Tang, Yunwei

2017-01-05

Since WorldView-2 (WV-2) images are widely used in various fields, there is a high demand for the use of high-quality pansharpened WV-2 images for different application purposes. With respect to the novelty of the WV-2 multispectral (MS) and panchromatic (PAN) bands, the performances of eight state-of-art pan-sharpening methods for WV-2 imagery including six datasets from three WV-2 scenes were assessed in this study using both quality indices and information indices, along with visual inspection. The normalized difference vegetation index, normalized difference water index, and morphological building index, which are widely used in applications related to land cover classification, the extraction of vegetation areas, buildings, and water bodies, were employed in this work to evaluate the performance of different pansharpening methods in terms of information presentation ability. The experimental results show that the Haze- and Ratio-based, adaptive Gram-Schmidt, Generalized Laplacian pyramids (GLP) methods using enhanced spectral distortion minimal model and enhanced context-based decision model methods are good choices for producing fused WV-2 images used for image interpretation and the extraction of urban buildings. The two GLP-based methods are better choices than the other methods, if the fused images will be used for applications related to vegetation and water-bodies.

Assessment of Pansharpening Methods Applied to WorldView-2 Imagery Fusion

PubMed Central

Li, Hui; Jing, Linhai; Tang, Yunwei

2017-01-01

Since WorldView-2 (WV-2) images are widely used in various fields, there is a high demand for the use of high-quality pansharpened WV-2 images for different application purposes. With respect to the novelty of the WV-2 multispectral (MS) and panchromatic (PAN) bands, the performances of eight state-of-art pan-sharpening methods for WV-2 imagery including six datasets from three WV-2 scenes were assessed in this study using both quality indices and information indices, along with visual inspection. The normalized difference vegetation index, normalized difference water index, and morphological building index, which are widely used in applications related to land cover classification, the extraction of vegetation areas, buildings, and water bodies, were employed in this work to evaluate the performance of different pansharpening methods in terms of information presentation ability. The experimental results show that the Haze- and Ratio-based, adaptive Gram-Schmidt, Generalized Laplacian pyramids (GLP) methods using enhanced spectral distortion minimal model and enhanced context-based decision model methods are good choices for producing fused WV-2 images used for image interpretation and the extraction of urban buildings. The two GLP-based methods are better choices than the other methods, if the fused images will be used for applications related to vegetation and water-bodies. PMID:28067770

Photochemical Reflectance Index (PRI) as a proxy of Light Use Efficiency (LUE) and transpiration in Mediterranean crop sites

NASA Astrophysics Data System (ADS)

LE Dantec, V.; Chebbi, W.; Boulet, G.; Merlin, O.; Lili-Chabaane, Z.; Er Raki, S.; Ceschia, E.; Khabba, S.; Fanise, P.; Zawilski, B.; Simonneaux, V.; Jarlan, L.

2016-12-01

The Photochemical Reflectance Index (PRI) is based on the short term reversible xanthophyll pigment changes accompanying plant stress and therefore of the associated photosynthetic activities. Strong relationships between PRI and Light Use Efficiency (LUE) were shown at leaf and canopy scales and over a wide range of species (Garbulsky et al., 2011). But very few previous works have explored the potential link with plant water status. In this study, we have first analyzed the link between PRI and LUE at canopy scale on two different crops in terms of canopy structure and crop management: olive grove (Tunisia) and wheat grown under different water regimes (irrigated or rainfed) and climate zones (France, Morocco). We have investigated the daily and seasonal dynamics of PRI; linking its variations to meteorological factors (global radiation and sun angle effects, soil water content, relative air humidity …) and plant processes. The highest correlations were mainly observed in clear skies conditions. We have found, whatever site, linear negative relationships between PRI and LUE using data acquired in midday (i.e. in solar zenithal angle condition). Linear link between PRI and sapflow measurements was also revealed. This correlation was obtained over periods characterized by a moderate soil water deficit, i.e. by when transpiration rate was mainly control by Vapor Pressure Deficit. We will then briefly presented alternative and complementary approaches to this index, to detect different level of water stress using thermal infrared emissions.

Remote sensing based water-use efficiency evaluation in sub-surface irrigated wine grape vines

NASA Astrophysics Data System (ADS)

Zúñiga, Carlos Espinoza; Khot, Lav R.; Jacoby, Pete; Sankaran, Sindhuja

2016-05-01

Increased water demands have forced agriculture industry to investigate better irrigation management strategies in crop production. Efficient irrigation systems, improved irrigation scheduling, and selection of crop varieties with better water-use efficiencies can aid towards conserving water. In an ongoing experiment carried on in Red Mountain American Viticulture area near Benton City, Washington, subsurface drip irrigation treatments at 30, 60 and 90 cm depth, and 15, 30 and 60% irrigation were applied to satisfy evapotranspiration demand using pulse and continuous irrigation. These treatments were compared to continuous surface irrigation applied at 100% evapotranspiration demand. Thermal infrared and multispectral images were acquired using unmanned aerial vehicle during the growing season. Obtained results indicated no difference in yield among treatments (p<0.05), however there was statistical difference in leaf temperature comparing surface and subsurface irrigation (p<0.05). Normalized vegetation index obtained from the analysis of multispectral images showed statistical difference among treatments when surface and subsurface irrigation methods were compared. Similar differences in vegetation index values were observed, when irrigation rates were compared. Obtained results show the applicability of aerial thermal infrared and multispectral images to characterize plant responses to different irrigation treatments and use of such information in irrigation scheduling or high-throughput selection of water-use efficient crop varieties in plant breeding.

Assessment of food-water nexus by water footprint: a case study in Saskatchewan, Canada

NASA Astrophysics Data System (ADS)

Zhao, Y.; Si, B.

2016-12-01

It is important but challengeable to understand the water-food nexus complexity. The water footprint (WF), a relatively new index, is a comprehensive indicator that can be used to evaluate crop water production. This paper aims to 1) determine how water footprint changes at different crop rotational types; 2) investigate what is difference if WF is calculated by yield-based or protein-based; and 3) explore how virtual water flows are responding to regional meteorological, agricultural, and socio-economic factors. The result provided the water footprint and virtual water flow exemplified for Saskatchewan agri-food production industries. By using the water footprint, we determined the best rotation for pulse crops in terms of efficiency of water productivity and water-saving opportunity. While yield is a comprehensive index to assess the productivity (yield-based WF), it underestimated the contribution of some crops, such as pulse crops with relatively low yield but high protein contents (protein-based WF). Consequently, we concluded that water-saving benefits can be achieved by the development and adoption of water efficient technology and better virtual water flows may be achieved by increased area of low water footprint in Saskatchewan. Our finding improves the current concepts of water and food security, informs production and trade decisions, and thus suggests optimal strategies by reduced water footprints in terms of agricultural management.

On the New Concept of the Available Water Climatology and Its Application

NASA Astrophysics Data System (ADS)

Byun, H. R.; Kim, D. W.; Choi, K. S.; Deo, R. C.; Lee, S. M.; Park, C. K.; Kwon, S. H.; Kim, G. B.; Kwon, H. N.

2014-12-01

We propose a new concept of climatology called the Available Water Climate (AWC). Available water is 'the remained water usable in every moment' that is calculated regardless of any time intervals or the amounts of precipitation. With this concept, the Available Water Resources Index (AWRI) has been digitized following the earlier work of Byun and Lee (2002). The applicability of AWRI not only to the assessment and prediction of water related disasters but also to the academic researches has been tested. Resulted merits are as follows. Firstly, the threshold value of AWRI for the occurrence of all water related disasters like flood, drought, inundation landslide, and drought each region became clear, therefore the assessment and the prediction of them became much more precise than before. It became clear that the more extreme the AWRI value is, the severer the related disasters become. As example, all disasters caused by heavy rains, even though a small inundation, became predictable at the time step of heavy rain warning with the help of the Long-term remained water index(LWI). As another example, the drought intensity and its dates on start and end are defined with more reasonably and precisely than any other drought indexes with help of the Effective drought index (EDI) using sliding time scale. Secondly, the spatiotemporal distribution of water environment were digitized clearly and objectively using AWRI and new concepts of the Water Abundant Season (WAS) and the Little Water Season (LIWAS), their dates on start and end, and their strength were defined, which is very beneficial for agriculture, forestry, and all other water controls. Also, the differences of water environments among regions were clearly digitized and the improvement of the climate classification by Köppen etc. became possible. Thirdly, other merits will be found continuously afterwards.

[Comparative study on promoting blood effects of Danshen-Honghua herb pair with different preparations based on chemometrics and multi-attribute comprehensive index methods].

PubMed

Qu, Cheng; Tang, Yu-Ping; Shi, Xu-Qin; Zhou, Gui-Sheng; Shang, Er-Xin; Shang, Li-Li; Guo, Jian-Ming; Liu, Pei; Zhao, Jing; Zhao, Bu-Chang; Duan, Jin-Ao

2017-08-01

To evaluate the promoting blood circulation and removing blood stasis effects of Danshen-Honghua(DH) herb pair with different preparations (alcohol, 50% alcohol and water) on blood rheology and coagulation functions in acute blood stasis rats, and optimize the best preparation method of DH based on principal component analysis(PCA), hierarchical cluster heatmap analysis and multi-attribute comprehensive index methods. Ice water bath and subcutaneous injection of adrenaline were both used to establish the acute blood stasis rat model. Then the blood stasis rats were administrated intragastrically with DH (alcohol, 50% alcohol and water) extracts. The whole blood viscosity(WBV), plasma viscosity(PV), erythrocyte sedimentation rate(ESR) and haematocrit(HCT) were tested to observe the effects of DH herb pair with different preparations and doses on hemorheology of blood stasis rats; the activated partial thromboplastin time(APTT), thrombin time(TT), prothrombin time(PT), and plasma fibrinogen(FIB) were tested to observe the effects of DH herb pair with different preparations on blood coagulation function and platelet aggregation of blood stasis rats. Then PCA, hierarchical cluster heatmap analysis and multi-attribute comprehensive index methods were all used to comprehensively evaluate the total promoting blood circulation and removing blood stasis effects of DH herb pair with different preparations. The hemorheological indexes and coagulation parameters of model group had significant differences with normal blank group. As compared with the model group, the DH herb pair with different preparations at low, middle and high doses could improve the blood hemorheology indexes and coagulation parameters in acute blood stasis rats with dose-effect relation. Based on the PCA, hierarchical cluster heatmap analysis and multi-attribute comprehensive index methods, the high dose group of 50% alcohol extract had the best effect of promoting blood circulation and removing blood stasis. Under the same dose but different preparations, 50% alcohol DH could obviously improve the hemorheology and blood coagulation function in acute blood stasis rats. These results suggested that DH herb pair with different preparations could obviously ameliorate the abnormality of hemorheology and blood coagulation function in acute blood stasis rats, and the optimized preparation of DH herb pair on promoting blood effects was 50% alcohol extract, providing scientific basis for more effective application of the DH herb pair in modern clinic medicine. Copyright© by the Chinese Pharmaceutical Association.

The environmental cost of a reference withdrawal from surface waters: Definition and geography

NASA Astrophysics Data System (ADS)

Soligno, Irene; Ridolfi, Luca; Laio, Francesco

2017-12-01

World freshwater ecosystems are significantly deteriorating at a faster rate than other ecosystems. Water withdrawals are recognized as one of the main drivers of growing water stress in river basins worldwide. Over the years, much effort has been devoted to quantify water withdrawals at a global scale; however, comparisons are not simple because the uneven spatiotemporal distribution of surface water resources entails that the same amount of consumed water does not have the same environmental cost in different times or places. In order to account for this spatiotemporal heterogeneity, this work proposes a novel index to assess the environmental cost of a withdrawal from a generic river section. The index depends on (i) the environmental relevance of the impacted fluvial ecosystem (e.g., bed-load transport capacity, width of the riparian belt, biodiversity richness) and (ii) the downstream river network affected by the water withdrawal. The environmental cost has been estimated in each and every river section worldwide considering a reference withdrawal. Being referred to a unitary reference withdrawal that can occur in any river section worldwide, our results can be suitably arranged for describing any scenario of surface water consumption (i.e., as the superposition of the actual pattern of withdrawals). The index aims to support the interpretation of the volumetric measure of surface water withdrawal with a perspective that takes into account the fluvial system where the withdrawal actually occurs. The application of the index highlights the river regions where withdrawals can cause higher environmental costs, with the challenge of weighting each water withdrawal considering the responsibilities that it has on downstream freshwater ecosystems.

Determination of the water quality index ratings of water in the Mpumalanga and North West provinces, South Africa

NASA Astrophysics Data System (ADS)

Wanda, Elijah M. M.; Mamba, Bhekie B.; Msagati, Titus A. M.

2016-04-01

This study reports on the water quality index (WQI) of wastewater and drinking water in the Mpumalanga and North West provinces of South Africa. The WQI is one of the most effective tools available to water sustainability researchers, because it provides an easily intelligible ranking of water quality on a rating scale from 0 to 100, based on the ascription of different weightings to several different parameters. In this study the WQI index ratings of wastewater and drinking water samples were computed according to the levels of pH, electrical conductivity (EC), biochemical oxygen demand (BOD), E. coli, temperature, turbidity and nutrients (nitrogen and phosphates) found in water samples collected from the two provinces between June and December, 2014. This study isolated three groups of WQ-rated waters, namely: fair (with a WQI range = 32.87-38.54%), medium (with a WQI range = 56.54-69.77%) and good (with a WQI range = 71.69-81.63%). More specifically, 23%, 23% and 54% of the sampled sites registered waters with fair, medium and good WQ ratings respectively. None of the sites sampled during the entire period of the project registered excellent or very good water quality ratings, which would ordinarily indicate that no treatment is required to make it fit for human consumption. Nevertheless, the results obtained by the Eerstehoek and Schoemansville water treatment plants in Mpumalanga and North West provinces, respectively, suggest that substantial improvement in the quality of water samples is possible, since the WQI values for all of the treated samples were higher than those for raw water. Presence of high levels of BOD, low levels of dissolved oxygen (DO), E. coli, nitrates and phosphates especially in raw water samples greatly affected their overall WQ ratings. It is recommended that a point-of-use system should be introduced to treat water intended for domestic purposes in the clean-water-deprived areas.

Land cover classification of Landsat 8 satellite data based on Fuzzy Logic approach

NASA Astrophysics Data System (ADS)

Taufik, Afirah; Sakinah Syed Ahmad, Sharifah

2016-06-01

The aim of this paper is to propose a method to classify the land covers of a satellite image based on fuzzy rule-based system approach. The study uses bands in Landsat 8 and other indices, such as Normalized Difference Water Index (NDWI), Normalized difference built-up index (NDBI) and Normalized Difference Vegetation Index (NDVI) as input for the fuzzy inference system. The selected three indices represent our main three classes called water, built- up land, and vegetation. The combination of the original multispectral bands and selected indices provide more information about the image. The parameter selection of fuzzy membership is performed by using a supervised method known as ANFIS (Adaptive neuro fuzzy inference system) training. The fuzzy system is tested for the classification on the land cover image that covers Klang Valley area. The results showed that the fuzzy system approach is effective and can be explored and implemented for other areas of Landsat data.

Application of water footprint combined with a unified virtual crop pattern to evaluate crop water productivity in grain production in China.

PubMed

Wang, Y B; Wu, P T; Engel, B A; Sun, S K

2014-11-01

Water shortages are detrimental to China's grain production while food production consumes a great deal of water causing water crises and ecological impacts. Increasing crop water productivity (CWP) is critical, so China is devoting significant resources to develop water-saving agricultural systems based on crop planning and agricultural water conservation planning. A comprehensive CWP index is necessary for such planning. Existing indices such as water use efficiency (WUE) and irrigation efficiency (IE) have limitations and are not suitable for the comprehensive evaluation of CWP. The water footprint (WF) index, calculated using effective precipitation and local water use, has advantages for CWP evaluation. Due to regional differences in crop patterns making the CWP difficult to compare directly across different regions, a unified virtual crop pattern is needed to calculate the WF. This project calculated and compared the WF of each grain crop and the integrated WFs of grain products with actual and virtual crop patterns in different regions of China for 2010. The results showed that there were significant differences for the WF among different crops in the same area or among different areas for the same crop. Rice had the highest WF at 1.39 m(3)/kg, while corn had the lowest at 0.91 m(3)/kg among the main grain crops. The WF of grain products was 1.25 m(3)/kg in China. Crop patterns had an important impact on WF of grain products because significant differences in WF were found between actual and virtual crop patterns in each region. The CWP level can be determined based on the WF of a virtual crop pattern, thereby helping optimize spatial distribution of crops and develop agricultural water savings to increase CWP. Copyright © 2014 Elsevier B.V. All rights reserved.

Assessing Nitrogen Status of Dryland Wheat Using the Canopy Chlorophyll Content Index

USDA-ARS?s Scientific Manuscript database

Ground-based, active light sensing relies upon the Normalized Difference Vegetation Index (NDVI) for assessing crop nitrogen (N) response and applying N fertilizer. However, NDVI may not work well in semiarid environments where biomass and yields depend upon plant water. This study evaluated the C...

Assessment of water quality: a case study of the Seybouse River (North East of Algeria)

NASA Astrophysics Data System (ADS)

Guettaf, M.; Maoui, A.; Ihdene, Z.

2017-03-01

The assessment of water quality has been carried out to determine the concentrations of different ions present in the surface waters. The Seybouse River constitutes a dump of industrial and domestic rejections which contribute to the degradation of water quality. A total of 48 surface water samples were collected from different stations. The first objective of this study is the use of water quality index (WQI) to evaluate the state of the water in this river. The second aim is to calculate the parameters of the quality of water destined for irrigation such as sodium adsorption ratio , sodium percentage, and residual sodium carbonate. A high mineralization and high concentration of major chemical elements and nutrients indicate inevitably a high value of WQI index. The mean value of electrical conductivity is about 945.25 µs/cm in the station 2 (Bouhamdane) and exceeds 1,400 µs/cm in station 12 of Nador. The concentration of sulfates is above 250 mg/l in the stations 8 (Zimba) and 11 (Helia). A concentration of orthophosphate over 2 mg/l was observed in the station 11. The comparison of the obtained and the WHO standards indicates a before using it use in agricultural purposes.

Prevalence of dental fluorosis among primary school children in association with different water fluoride levels in Mysore district, Karnataka.

PubMed

Sebastian, Shibu Thomas; Soman, Rino Roopak; Sunitha, S

2016-01-01

Fluoride intake at optimal level decreases the incidence of dental caries. However, excessive intake, especially during developmental stages can cause adverse effects such as dental and skeletal fluorosis. To assess the prevalence and severity of dental fluorosis in primary school children born and raised in three villages of Mysore District. The three selected villages have different water fluoride concentrations. Three villages namely, Nerale (water fluoride 2.0 ppm), Belavadi (1.2 ppm) and Naganahally (0.4 ppm) were selected for the study. Then, a total of 405 children, 10-12-year-old (204 [50.4%] males and 201 [49.60%] females) were selected from three schools of the villages. Dean's fluorosis index recommended by World Health Organization was used to evaluate fluorosis among the study population. The overall prevalence of dental fluorosis was found to be 41.73%. An increase in the community fluorosis index (CFI) was higher among those living in high water fluoride area. A significantly positive correlation was found between CFI and water fluoride concentration in drinking water.

Developing index maps of water-harvest potential in Africa

USGS Publications Warehouse

Senay, G.B.; Verdin, J.P.

2004-01-01

The food security problem in Africa is tied to the small farmer, whose subsistence farming relies heavily on rain-fed agriculture. A dry spell lasting two to three weeks can cause a significant yield reduction. A small-scale irrigation scheme from small-capacity ponds can alleviate this problem. This solution would require a water harvest mechanism at a farm level. In this study, we looked at the feasibility of implementing such a water harvest mechanism in drought prone parts of Africa. A water balance study was conducted at different watershed levels. Runoff (watershed yield) was estimated using the SCS curve number technique and satellite derived rainfall estimates (RFE). Watersheds were delineated from the Africa-wide HYDRO-1K digital elevation model (DEM) data set in a GIS environment. Annual runoff volumes that can potentially be stored in a pond during storm events were estimated as the product of the watershed area and runoff excess estimated from the SCS Curve Number method. Estimates were made for seepage and net evaporation losses. A series of water harvest index maps were developed based on a combination of factors that took into account the availability of runoff, evaporation losses, population density, and the required watershed size needed to fill a small storage reservoir that can be used to alleviate water stress during a crop growing season. This study presents Africa-wide water-harvest index maps that could be used for conducting feasibility studies at a regional scale in assessing the relative differences in runoff potential between regions for the possibility of using ponds as a water management tool. ?? 2004 American Society of Agricultural Engineers.

Cold pressor-induced pain does not impair WAIS-IV processing speed index or working memory index performance.

PubMed

Etherton, Joseph

2014-01-01

Chronic pain frequently involves cognitive complaints such as concentration and memory deficits, but studies of the effects of pain on cognition have not consistently demonstrated deficits and have not typically utilized standard neuropsychological instruments. Effects of cold pressor-induced pain on Wechsler Adult Intelligence Scale-Fourth Edition Processing Speed Index (PSI) and Working Memory Index (WMI) performance was examined in nonclinical volunteers (n = 40). All took one PSI subtest and one WMI subtest normally, and then took different PSI and WMI subtests during cold pressor-induced pain or painless warm-water immersion. Scaled scores for normal administration versus pain or painless water immersion did not differ and there was no interaction between group (control vs. pain) and manner of administration, despite moderately severe mean pain ratings (M = 6.8 on a 0-10 pain-rating scale). Results indicate that induced pain in nonclinical volunteers does not impair PSI or WMI performance, and they suggest that chronic pain per se should not be expected to substantially affect these cognitive functions. However, patients with chronic pain may differ from nonclinical volunteers in their experience of pain, potentially limiting generalizability.

Comparison of remote sensing indices for monitoring of desert cienegas

USGS Publications Warehouse

Wilson, Natalie R.; Norman, Laura M.; Villarreal, Miguel; Gass, Leila; Tiller, Ron; Salywon, Andrew

2016-01-01

This research considers the applicability of different vegetation indices at 30 m resolution for mapping and monitoring desert wetland (cienega) health and spatial extent through time at Cienega Creek in southeastern Arizona, USA. Multiple stressors including the risk of decadal-scale drought, the effects of current and predicted global warming, and continued anthropogenic pressures threaten aquatic habitats in the southwest and cienegas are recognized as important sites for conservation and restoration efforts. However, cienegas present a challenge to satellite-imagery based analysis due to their small size and mixed surface cover of open water, exposed soils, and vegetation. We created time series of five well-known vegetation indices using annual Landsat Thematic Mapper (TM) images retrieved during the April–June dry season, from 1984 to 2011 to map landscape-level distribution of wetlands and monitor the temporal dynamics of individual sites. Indices included the Normalized Difference Vegetation Index (NDVI), the Soil-Adjusted Vegetation Index (SAVI), the Normalized Difference Water Index (NDWI), and the Normalized Difference Infrared Index (NDII). One topographic index, the Topographic Wetness Index (TWI), was analyzed to examine the utility of topography in mapping distribution of cienegas. Our results indicate that the NDII, calculated using Landsat TM band 5, outperforms the other indices at differentiating cienegas from riparian and upland sites, and was the best means to analyze change. As such, it offers a critical baseline for future studies that seek to extend the analysis of cienegas to other regions and time scales, and has broader applicability to the remote sensing of wetland features in arid landscapes.

An evaluation method of the sustainability of water resource in karst region: a case study of Zunyi, China

NASA Astrophysics Data System (ADS)

Li, Bo; Wang, Ganlu; Ding, Hanghang; Chen, Yulong

2017-06-01

Water resource is of great significance to the survival and development of human. However, the water resource system in karst regions is sensitive to external interference owing to the special geological processes which cause soil impoverishment, severe rocky desertification and large topographic height difference. Therefore, evaluating the sustainability of the water resource in karst regions is beneficial to reasonably use and protect water resource. This paper puts forward to evaluate the water resource from four aspects, including water resources system, water requirement system, ecosystem and social economic system. Moreover, on this basis, 18 evaluation indexes were selected to construct the sustainability evaluation index system and method. This method was used to evaluate the sustainability of the water resource in the typical karst region—Zunyi, Guizhou province, China, and was verified according to the actual situation in the research area. All these provide reference for the evaluation of the sustainability of the water resource in similar regions.

Variation of Biophysical Parameters of the Skin with Age, Gender, and Body Region

PubMed Central

Firooz, Alireza; Sadr, Bardia; Babakoohi, Shahab; Sarraf-Yazdy, Maryam; Fanian, Ferial; Kazerouni-Timsar, Ali; Nassiri-Kashani, Mansour; Naghizadeh, Mohammad Mehdi; Dowlati, Yahya

2012-01-01

Background. Understanding the physiological, chemical, and biophysical characteristics of the skin helps us to arrange a proper approach to the management of skin diseases. Objective. The aim of this study was to measure 6 biophysical characteristics of normal skin (sebum content, hydration, transepidermal water loss (TEWL), erythema index, melanin index, and elasticity) in a normal population and assess the effect of sex, age, and body location on them. Methods. Fifty healthy volunteers in 5 age groups (5 males and females in each) were enrolled in this study. A multifunctional skin physiology monitor (Courage & Khazaka electronic GmbH, Germany) was used to measure skin sebum content, hydration, TEWL, erythema index, melanin index, and elasticity in 8 different locations of the body. Results. There were significant differences between the hydration, melanin index, and elasticity of different age groups. Regarding the locations, forehead had the highest melanin index, where as palm had the lowest value. The mean values of erythema index and melanin index and TEWL were significantly higher in males and anatomic location was a significant independent factor for all of 6 measured parameters. Conclusion. Several biophysical properties of the skin vary among different gender, age groups, and body locations. PMID:22536139

An annual quasidifference approach to water price elasticity

NASA Astrophysics Data System (ADS)

Bell, David R.; Griffin, Ronald C.

2008-08-01

The preferred price specification for retail water demand estimation has not been fully settled by prior literature. Empirical consistency of price indices is necessary to enable testing of competing specifications. Available methods of unbiasing the price index are summarized here. Using original rate information from several hundred Texas utilities, new indices of marginal and average price change are constructed. Marginal water price change is shown to explain consumption variation better than average water price change, based on standard information criteria. Annual change in quantity consumed per month is estimated with differences in climate variables and the new quasidifference marginal price index. As expected, the annual price elasticity of demand is found to vary with daily high and low temperatures and the frequency of precipitation.

Analysis of vegetation recovery surrounding a restored wetland using the normalized difference infrared index (NDII) and normalized difference vegetation index (NDVI)

USGS Publications Warehouse

Wilson, Natalie R.; Norman, Laura

2018-01-01

Watershed restoration efforts seek to rejuvenate vegetation, biological diversity, and land productivity at Cienega San Bernardino, an important wetland in southeastern Arizona and northern Sonora, Mexico. Rock detention and earthen berm structures were built on the Cienega San Bernardino over the course of four decades, beginning in 1984 and continuing to the present. Previous research findings show that restoration supports and even increases vegetation health despite ongoing drought conditions in this arid watershed. However, the extent of restoration impacts is still unknown despite qualitative observations of improvement in surrounding vegetation amount and vigor. We analyzed spatial and temporal trends in vegetation greenness and soil moisture by applying the normalized difference vegetation index (NDVI) and normalized difference infrared index (NDII) to one dry summer season Landsat path/row from 1984 to 2016. The study area was divided into zones and spectral data for each zone was analyzed and compared with precipitation record using statistical measures including linear regression, Mann– Kendall test, and linear correlation. NDVI and NDII performed differently due to the presence of continued grazing and the effects of grazing on canopy cover; NDVI was better able to track changes in vegetation in areas without grazing while NDII was better at tracking changes in areas with continued grazing. Restoration impacts display higher greenness and vegetation water content levels, greater increases in greenness and water content through time, and a decoupling of vegetation greenness and water content from spring precipitation when compared to control sites in nearby tributary and upland areas. Our results confirm the potential of erosion control structures to affect areas up to 5 km downstream of restoration sites over time and to affect 1 km upstream of the sites.

The influence of changes in land use and landscape patterns on soil erosion in a watershed.

PubMed

Zhang, Shanghong; Fan, Weiwei; Li, Yueqiang; Yi, Yujun

2017-01-01

It is very important to have a good understanding of the relation between soil erosion and landscape patterns so that soil and water conservation in river basins can be optimized. In this study, this relationship was explored, using the Liusha River Watershed, China, as a case study. A distributed water and sediment model based on the Soil and Water Assessment Tool (SWAT) was developed to simulate soil erosion from different land use types in each sub-basin of the Liusha River Watershed. Observed runoff and sediment data from 1985 to 2005 and land use maps from 1986, 1995, and 2000 were used to calibrate and validate the model. The erosion modulus for each sub-basin was calculated from SWAT model results using the different land use maps and 12 landscape indices were chosen and calculated to describe the land use in each sub-basin for the different years. The variations in instead of the absolute amounts of the erosion modulus and the landscape indices for each sub-basin were used as the dependent and independent variables, respectively, for the regression equations derived from multiple linear regression. The results indicated that the variations in the erosion modulus were closely related to changes in the large patch index, patch cohesion index, modified Simpson's evenness index, and the aggregation index. From the regression equation and the corresponding landscape indices, it was found that watershed erosion can be reduced by decreasing the physical connectivity between patches, improving the evenness of the landscape patch types, enriching landscape types, and enhancing the degree of aggregation between the landscape patches. These findings will be useful for water and soil conservation and for optimizing the management of watershed landscapes. Copyright © 2016 Elsevier B.V. All rights reserved.

Study of different pretreatments for reverse osmosis reclamation of a petrochemical secondary effluent.

PubMed

Benito-Alcázar, C; Vincent-Vela, M C; Gozálvez-Zafrilla, J M; Lora-García, J

2010-06-15

Conventionally treated petrochemical wastewaters contain substantial quantities of hazardous pollutants. In addition, wastewater reuse is being enhanced as a consequence of the shortage of fresh water. Advanced petrochemical wastewater treatment for water reuse will reduce hazardous pollutants discharges as well as water consumption. Reverse osmosis is a suitable technology to obtain pure water. This work studies the adequacy of different pretreatments applied to a petrochemical secondary effluent to produce a suitable feeding for reverse osmosis treatment. The permeate obtained can be used in the petrochemical industry for different processes. In this work, several experiments (granulated activated carbon filtration, ultrafiltration, nanofiltration and granulated activated carbon filtration coupled with nanofiltration) were performed to improve the conventional pretreatment. Total organic carbon, chemical oxygen demand, turbidity and silt density index were used to evaluate water quality for reverse osmosis feeding. In granulated activated carbon filtration, all the measured parameters but silt density index indicated a good filtrate quality to feed reverse osmosis membranes. Although the ultrafiltration permeate obtained was suitable for reverse osmosis, nanofiltration and granulated activated carbon filtration coupled with NF provided a better effluent quality for reverse osmosis than the other pretreatments studied. Copyright 2010 Elsevier B.V. All rights reserved.

Developing a Vulnerability Mapping Methodology: Applying the Water-Associated Disease Index to Dengue in Malaysia

PubMed Central

Dickin, Sarah K.; Schuster-Wallace, Corinne J.; Elliott, Susan J.

2013-01-01

The Water-associated Disease Index (WADI) was developed to identify and visualize vulnerability to different water-associated diseases by integrating a range of social and biophysical determinants in map format. In this study vulnerability is used to encompass conditions of exposure, susceptibility, and differential coping capacity to a water-associated health hazard. By assessing these conditions, the tool is designed to provide stakeholders with an integrated and long-term understanding of subnational vulnerabilities to water-associated disease and contribute to intervention strategies to reduce the burden of illness. The objective of this paper is to describe and validate the WADI tool by applying it to dengue. A systemic ecohealth framework that considers links between people, the environment and health was applied to identify secondary datasets, populating the index with components including climate conditions, land cover, education status and water use practices. Data were aggregated to create composite indicators of exposure and of susceptibility in a Geographic Information System (GIS). These indicators were weighted by their contribution to dengue vulnerability, and the output consisted of an overall index visualized in map format. The WADI was validated in this Malaysia case study, demonstrating a significant association with dengue rates at a sub-national level, and illustrating a range of factors that drive vulnerability to the disease within the country. The index output indicated high vulnerability to dengue in urban areas, especially in the capital Kuala Lumpur and surrounding region. However, in other regions, vulnerability to dengue varied throughout the year due to the influence of seasonal climate conditions, such as monsoon patterns. The WADI tool complements early warning models for water-associated disease by providing upstream information for planning prevention and control approaches, which increasingly require a comprehensive and geographically broad understanding of vulnerability for implementation. PMID:23667642

Nocturnal Polyuria: Excess of Nocturnal Urine Production, Excess of Definitions-Influence on Renal Function Profile.

PubMed

Goessaert, An-Sofie; Walle, Johan Vande; Bosch, Ruud; Hoebeke, Piet; Everaert, Karel

2016-03-01

This study aimed to identify important differences in renal function profile, and potential water and sodium diuresis cutoffs among participants with nocturnal polyuria according to nocturnal polyuria definitions. This post hoc analysis was based on a prospective study in which participants completed a bladder diary, collected urine and provided a blood sample. With an age dependent nocturnal polyuria index greater than 20% to 33% as the referent 4 definitions of nocturnal polyuria were compared, including 1) nocturnal polyuria index greater than 33%, 2) nocturnal urine production greater than 90 ml per hour and 3) greater than 10 ml/kg, and 4) nocturia index greater than 1.5. In 112 male and female participants significant differences in baseline characteristics and bladder diary parameters were found according to definition. Diuresis rate, free water clearance and sodium clearance had similar 24-hour courses in the subgroups with and without polyuria by each definition. The range varied more in the subgroup with vs without polyuria, especially at night for diuresis rate and free water clearance. At night the latter decreased in the polyuria subgroup based on each definition (p <0.001 to 0.045). A significant difference vs the no polyuria subgroups was found only for urine production greater than 90 ml per hour and polyuria index greater than 20% to 33%. For each definition sodium clearance remained high in the polyuria subgroup, which differed significantly from the no polyuria subgroups (p <0.001 to 0.030). Free water and sodium clearance cutoffs ranged from -0.65 to -0.85 ml per minute between 12 and 2 a.m., and 0.65 to 0.77 ml per minute between 3 and 5 a.m., respectively, with large sensitivity and specificity differences according to definition. There were important differences when comparing participants with vs without nocturnal polyuria by definition. The renal function profile indicating the pathophysiological mechanism of nocturnal polyuria did not seem to be influenced by definition but free water clearance and sodium clearance cutoff sensitivity differed substantially. These results must be confirmed in a larger homogeneous sample. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Development of Dimensionless Index Assessing Low Impact Development in Urban Areas

NASA Astrophysics Data System (ADS)

Jun, S. H.; Lee, E. H.; Kim, J. H.

2017-12-01

Because the rapid urbanization and industrialization have increased the impervious area of watersheds, inundation in urban area and water pollution of river by non-point pollutants have caused serious problems for a long time. Low Impact Development (LID) techniques have been implemented for the solution of these problems due to its cost effectiveness for mitigating the water quality and quantity impact on urban areas. There have been many studies about the effectiveness of LID, but there is a lack of research on developing an index for the assessment of LID performance. In this study, the dimensionless reliability index of LID is proposed. The index is developed using Distance Measure Method (DMM). DMM is used to consider the parameters that have different units. The parameters for reliability of LID are the amount of pollutant at the outfall and the flooding volume. Both parameters become dimensionless index by DMM. Weighted factors in dimensionless index are considered to realize the behavior of reliability for the variation of importance to the parameters. LID is applied to an actual area called Gasan city in Seoul, South Korea where inundation is frequently occurred. The reliability is estimated for 16 different rainfall events. For each rainfall event, the parameters with LID installation are compared with those of no LID installation. Depending on which parameter is considered more important, the results showed difference. In conclusion, the optimal locations of LID are suggested as the weighted factors change.

Forecasting and Monitoring Agricultural Drought in the Philippines

NASA Astrophysics Data System (ADS)

Perez, G. J.; Macapagal, M.; Olivares, R.; Macapagal, E. M.; Comiso, J. C.

2016-06-01

A monitoring and forecasting sytem is developed to assess the extent and severity of agricultural droughts in the Philippines at various spacial scales and across different time periods. Using Earth observation satellite data, drought index, hazard and vulnerability maps are created. The drought index, called Standardized Vegetation-Temperature Ratio (SVTR), is derived using the Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST). SVTR is evaluated by correlating its values with existing agricultural drought index, particulary Evaporative Stress Index (ESI). Moreover, the performance of SVTR in detecting drought occurrences was assessed for the 2015-2016 drought event. This period is a strong El Niño year and a large portion of the country was affected by drought at varying degrees, making it a good case study for evaluating drought indices. Satellitederived SVTR was validated through several field visits and surveys across different major agricultural areas in the country, and was found to be 73% accurate. The drought hazard and vulnerability maps are produced by utilizing the evapotranspration product of MODIS, rainfall climatology from the Tropical Rainfall Microwave Mission (TRMM) and ancillary data, including irrigation, water holding capacity and land use. Finally, we used statistical techniques to determine trends in NDVI and LST and generate a sixmonth forecast of drought index. Outputs of this study are being assessed by the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) and the Department of Agriculture Bureau of Soils and Water Management (DABSWM) for future integration in their operations.

Variation in stream diatom communities in relation to water quality and catchment variables in a boreal, urbanized region.

PubMed

Teittinen, Anette; Taka, Maija; Ruth, Olli; Soininen, Janne

2015-10-15

Intensive anthropogenic land use such as urbanization alters the hydrological cycle, water chemistry and physical habitat characteristics, thus impairing stream physicochemical and biological quality. Diatoms are widely used to assess stream water quality as they integrate water chemistry temporally and reflect the joint influence of multiple stressors on stream biota. However, knowledge of the major community patterns of diatoms in urban streams remains limited especially in boreal regions. The aim of this study was to examine the effects of water chemistry and catchment characteristics on stream diatom communities, and to test the performance of the Index of Pollution Sensitivity (IPS) as a stream water quality indicator across an urban-to-rural gradient in southern Finland. Diatom community structure and species richness were related to local-scale variables such as water temperature, aluminium concentration, and electrical conductivity, which were in turn influenced by patterns in catchment land use and land cover. Diatoms reflected the intensity of human activities as more intensive land use increased the occurrence of pollution-tolerant species. The change in community structure along the land use intensity gradient was accompanied by a distinct decline in species richness. On the contrary, the IPS index failed to indicate differences in water quality along the urban-to-rural gradient as no consistent differences in the IPS values were found. Our results highlight the joint influence of multifaceted factors that underlie diatom patterns, and show that diatom biodiversity can be used as cost-effective metric indicating urban stream conditions. However, the IPS index turned out to be an unsuitable tool for assessing water quality among these streams. Copyright © 2015 Elsevier B.V. All rights reserved.

Variability of basin scale water resources indicators derived from global hydrological and land surface models

NASA Astrophysics Data System (ADS)

Werner, Micha; Blyth, Eleanor; Schellekens, Jaap

2016-04-01

Global hydrological and land-surface models are becoming increasingly available, and as the resolution of these improves, as well how hydrological processes are represented, so does their potential. These offer consistent datasets at the global scale, which can be used to establish water balances and derive policy relevant indicators in medium to large basins, including those that are poorly gauged. However, differences in model structure, model parameterisation, and model forcing may result in quite different indicator values being derived, depending on the model used. In this paper we explore indicators developed using four land surface models (LSM) and five global hydrological models (GHM). Results from these models have been made available through the Earth2Observe project, a recent research initiative funded by the European Union 7th Research Framework. All models have a resolution of 0.5 arc degrees, and are forced using the same WATCH-ERA-Interim (WFDEI) meteorological re-analysis data at a daily time step for the 32 year period from 1979 to 2012. We explore three water resources indicators; an aridity index, a simplified water exploitation index; and an indicator that calculates the frequency of occurrence of root zone stress. We compare indicators derived over selected areas/basins in Europe, Colombia, Southern Africa, the Indian Subcontinent and Australia/New Zealand. The hydrological fluxes calculated show quite significant differences between the nine models, despite the common forcing dataset, with these differences reflected in the indicators subsequently derived. The results show that the variability between models is related to the different climates types, with that variability quite logically depending largely on the availability of water. Patterns are also found in the type of models that dominate different parts of the distribution of the indicator values, with LSM models providing lower values, and GHM models providing higher values in some climates, and vice versa in others. How important this variability is in supporting a policy decision, depends largely on how a decision thresholds are set. For example in the case of the aridity index, with areas being denoted as arid with an index of 0.6 or above, we show that the variability is primarily of interest in transitional climates, such as the Mediterranean The analysis shows that while both LSM's and GHM's provide useful data, indices derived to support water resources management planning may differ substantially, depending on the model used. The analysis also identifies in which climates improvements to the models are particularly relevant to support the confidence with which decisions can be taken based on derived indicators.

Better almond water stress monitoring using fractional-order moments of non-normalized difference vegetation index

USDA-ARS?s Scientific Manuscript database

Stem water potential (SWP) has become a very popular tool for farmers to monitor the water status of almond trees. However, it is labor intensive and time consuming to scale up the measurements in the large field. With the development of unmanned aerial vehicles (UAVs) and sensing payload, it become...

The inequality of water scarcity events: who is actually being affected?

NASA Astrophysics Data System (ADS)

Veldkamp, Ted I. E.; Wada, Yoshihide; Kummu, Matti; Aerts, Jeroen C. J. H.; Ward, Philip J.

2015-04-01

Over the past decades, changing hydro-climatic and socioeconomic conditions increased regional and global water scarcity problems. In the near future, projected changes in human water use and population growth - in combination with climate change - are expected to aggravate water scarcity conditions and its associated impacts on our society. Whilst a wide range of studies have modelled past and future regional and global patterns of change in population or land area impacted by water scarcity conditions, less attention is paid on who is actually affected and how vulnerable this share of the population is to water scarcity conditions. The actual impact of water scarcity events, however, not only depends on the numbers being affected, but merely on how sensitive this population is to water scarcity conditions, how quick and efficient governments can deal with the problems induced by water scarcity, and how many (financial and infrastructural) resources are available to cope with water scarce conditions. Only few studies have investigated the above mentioned interactions between societal composition and water scarcity conditions (e.g. by means of the social water scarcity index and the water poverty index) and, up to our knowledge, a comprehensive global analysis including different water scarcity indicators and multiple climate and socioeconomic scenarios is missing. To address this issue, we assess in this contribution the adaptive capacity of a society to water scarcity conditions, evaluate how this may be driven by different societal factors, and discuss how enhanced knowledge on this topic could be of interest for water managers in their design of adaptation strategies coping with water scarcity events. For that purpose, we couple spatial information on water scarcity conditions with different components from, among others, the Human Development Index and the Worldwide Governance Indicators, such as: the share of the population with an income below the poverty line; mean year of schooling; the ratio between urban and rural population; import and export rates; political stability; corruption; and government effectiveness. Moreover, we also take into account the accessibility of fresh water bodies and markets. Underlying water scarcity conditions were estimated as follows: (1) yearly water availability was calculated at 0.5° x 0.5° over the period 1971-2099 using daily discharge and run-off fields from the global hydrological model PCR-GLOBWB, forced with different climate change scenarios; (2) statistical methods were applied to fit probability density functions to time-series of yearly water availability and to estimate water availability for a number of return periods covering the current, 2030, and 2050 conditions; (3) water availability results were assembled with scenario estimates of water consumption and population density which resulted in a series of water scarcity estimates.

Changes of glacier, glacier-fed rivers and lakes in Altai Tavan Bogd National Park, Western Mongolia, based on multispectral satellite data from 1990 to 2017

NASA Astrophysics Data System (ADS)

Batsaikhan, B.; Lkhamjav, O.; Batsaikhan, N.

2017-12-01

Impacts on glaciers and water resource management have been altering through climate changes in Mongolia territory characterized by dry and semi-arid climate with low precipitation. Melting glaciers are early indicators of climate change unlike the response of the forests which is slower and takes place over a long period of time. Mountain glaciers are important environmental components of local, regional, and global hydrological cycles. The study calculates an overview of changes for glacier, glacier-fed rivers and lakes in Altai Tavan Bogd mountain, the Western Mongolia, based on the indexes of multispectral data and the methods typically applied in glacier studies. Were utilized an integrated approach of Normalized Difference Snow Index (NDSI) and Normalized Difference Water Index (NDWI) to combine Landsat, MODIS imagery and digital elevation model, to identify glacier cover are and quantify water storage change in lakes, and compared that with and climate parameters including precipitation, land surface temperature, evaporation, moisture. Our results show that melts of glacier at the study area has contributed to significantly increase of water storage of lakes in valley of The Altai Tavan Bogd mountain. There is hydrologic connection that lake basin is directly fed by glacier meltwater.

Spectral Reflectance and Vegetation Index Changes in Deciduous Forest Foliage Following Tree Removal: Potential for Deforestation Monitoring

NASA Astrophysics Data System (ADS)

Peng, D.; Hu, Y.; Li, Z.

2016-05-01

It is important to detect and quantify deforestation to guide strategic decisions regarding environment, socioeconomic development, and climate change. In the present study, we conducted a field experiment to examine spectral reflectance and vegetation index changes in poplar and locust tree foliage with different leaf area indices over the course of three sunny days, following tree removal from the canopy. The spectral reflectance of foliage from harvested trees was measured using an ASD FieldSpec Prospectroradiometer; synchronous meteorological data were also obtained. We found that reflectance in short-wave infrared and red-edge reflectance was more time sensitive after tree removal than reflectance in other spectral regions, and that the normalized difference water index (NDWI) and the red-edge chlorophyll index (CIRE) were the preferred indicators of these changes from several indices evaluated. Synthesized meteorological environments were found to influence water and chlorophyll contents after tree removal, and this subsequently changed the spectral canopy reflectance. Our results indicate the potential for such tree removal to be detected with NDWI or CIRE from the second day of a deforestation event.

Remote Sensing Analysis of Volume in Taihu Lake: Application for Icesat/hydroweb and Landsat Data

NASA Astrophysics Data System (ADS)

Liu, Y.; Li, Y.; Lu, Y.; Yue, H.

2018-04-01

In order to evaluate the fluctuation of Taihui Lake, ICESat/Hydroweb and Landsat data recorded from 1975 to 2015 were used to examine changes in lake level and area, derived from Normalized Difference Water Index (NDWI) and Modified Normalized Difference Water Index (MNDWI), which are combined to indirectly evaluate water volume variations and water balance of Taihu Lake. The results show that the time series of lake area and volume variations of Taihu Lake exhibit a gradually increasing trend from 1975 to 2015 and the value rose from 2320.07 km2 and -0.0470 km3, respectively in 1975 to 2341.06 km2 and 0.2759 km3, respectively in 2015. The water level of Taihu Lake demonstrates a fluctuating trend during 1975-2015 and the value changed from 0.9826 m in 1975 to 1.1359 m in 2015. There was a moderate correlation for Taihu Lake (R2 ≈ 0.65) between water level and surface area. The water volume changes was in very good agreement for lake level changes and surface area variations (R2 > 0.85). Combining with lake level and area changes, water balance of Taihu Lake was acquired and it shows a positive water budgets of 0.0092 km3 during past 40 years.

Application of Aquatic Insects (Ephemeroptera, Plecoptera And Trichoptera) In Water Quality Assessment of Malaysian Headwater

PubMed Central

Ab Hamid, Suhaila; Md Rawi, Che Salmah

2017-01-01

The Ephemeroptera, Plecoptera and Trichoptera (EPT) community structure and the specific sensitivity of certain EPT genera were found to be influenced by water parameters in the rivers of Gunung Jerai Forest Reserve (GJFR) in the north of peninsular Malaysia. The scores of EPT taxa richness of >10 in all rivers indicated all rivers’ habitats were non-impacted, having good water quality coinciding with Class I and Class II of Malaysian water quality index (WQI) classification of potable water. The abundance of EPT was very high in Teroi River (9,661 individuals) but diversity was lower (22 genera) than Tupah River which was highly diverse (28 genera) but lower in abundance (4,263 individuals). The lowest abundance and moderate diversity was recorded from Batu Hampar River (25 genera). Baetis spp. and Thalerosphyrus spp., Neoperla spp. and Cheumatopsyche spp. were the most common genera found. Classification for all rivers using EPT taxa Richness Index and WQI gave different category of water quality, respectively. The WQI classified Tupah and Batu Hampar rivers into Class II and Teroi River (Class I) was two classes above the classification of the EPT taxa Richness Index. PMID:28890767

Application of Aquatic Insects (Ephemeroptera, Plecoptera And Trichoptera) In Water Quality Assessment of Malaysian Headwater.

PubMed

Ab Hamid, Suhaila; Md Rawi, Che Salmah

2017-07-01

The Ephemeroptera, Plecoptera and Trichoptera (EPT) community structure and the specific sensitivity of certain EPT genera were found to be influenced by water parameters in the rivers of Gunung Jerai Forest Reserve (GJFR) in the north of peninsular Malaysia. The scores of EPT taxa richness of >10 in all rivers indicated all rivers' habitats were non-impacted, having good water quality coinciding with Class I and Class II of Malaysian water quality index (WQI) classification of potable water. The abundance of EPT was very high in Teroi River (9,661 individuals) but diversity was lower (22 genera) than Tupah River which was highly diverse (28 genera) but lower in abundance (4,263 individuals). The lowest abundance and moderate diversity was recorded from Batu Hampar River (25 genera). Baetis spp. and Thalerosphyrus spp., Neoperla spp. and Cheumatopsyche spp. were the most common genera found. Classification for all rivers using EPT taxa Richness Index and WQI gave different category of water quality, respectively. The WQI classified Tupah and Batu Hampar rivers into Class II and Teroi River (Class I) was two classes above the classification of the EPT taxa Richness Index.

A robust Multi-Band Water Index (MBWI) for automated extraction of surface water from Landsat 8 OLI imagery

NASA Astrophysics Data System (ADS)

Wang, Xiaobiao; Xie, Shunping; Zhang, Xueliang; Chen, Cheng; Guo, Hao; Du, Jinkang; Duan, Zheng

2018-06-01

Surface water is vital resources for terrestrial life, while the rapid development of urbanization results in diverse changes in sizes, amounts, and quality of surface water. To accurately extract surface water from remote sensing imagery is very important for water environment conservations and water resource management. In this study, a new Multi-Band Water Index (MBWI) for Landsat 8 Operational Land Imager (OLI) images is proposed by maximizing the spectral difference between water and non-water surfaces using pure pixels. Based on the MBWI map, the K-means cluster method is applied to automatically extract surface water. The performance of MBWI is validated and compared with six widely used water indices in 29 sites of China. Results show that our proposed MBWI performs best with the highest accuracy in 26 out of the 29 test sites. Compared with other water indices, the MBWI results in lower mean water total errors by a range of 9.31%-25.99%, and higher mean overall accuracies and kappa coefficients by 0.87%-3.73% and 0.06-0.18, respectively. It is also demonstrated for MBWI in terms of robustly discriminating surface water from confused backgrounds that are usually sources of surface water extraction errors, e.g., mountainous shadows and dark built-up areas. In addition, the new index is validated to be able to mitigate the seasonal and daily influences resulting from the variations of the solar condition. MBWI holds the potential to be a useful surface water extraction technology for water resource studies and applications.

Integrated risk assessment and screening analysis of drinking water safety of a conventional water supply system.

PubMed

Sun, F; Chen, J; Tong, Q; Zeng, S

2007-01-01

Management of drinking water safety is changing towards an integrated risk assessment and risk management approach that includes all processes in a water supply system from catchment to consumers. However, given the large number of water supply systems in China and the cost of implementing such a risk assessment procedure, there is a necessity to first conduct a strategic screening analysis at a national level. An integrated methodology of risk assessment and screening analysis is thus proposed to evaluate drinking water safety of a conventional water supply system. The violation probability, indicating drinking water safety, is estimated at different locations of a water supply system in terms of permanganate index, ammonia nitrogen, turbidity, residual chlorine and trihalomethanes. Critical parameters with respect to drinking water safety are then identified, based on which an index system is developed to prioritize conventional water supply systems in implementing a detailed risk assessment procedure. The evaluation results are represented as graphic check matrices for the concerned hazards in drinking water, from which the vulnerability of a conventional water supply system is characterized.

Water Quality Evaluation of PET Bottled Water by Mineral Balance in the Northeast Asian Region: A Case Study of South Korea.

PubMed

Houri, Daisuke; Koo, Chung Mo

2015-09-01

The past few years have seen a demand for drinking water in contemporary society with a focus on safety and taste. Mineral water is now marketed as a popular commercial product and, partly due to health concerns, the production. For the study, a comparison was carried out of water samples from 9 types of polyethylene terephthalate (PET) bottled water sold in South Korea as well as from tap water in the cities of Seoul and Chuncheon. These were compared with samples of Japanese PET bottled water in order to determine shared commonalities and identify individual characteristics. To evaluate water quality objectively, we quantified the elements contained in the water samples. Samples were assessed not with the usual sensory evaluation but with the evaluation approach advocated by Hashimoto et al. which employs the Water Index of Taste and the Water Index of Health. The levels of water quality obtained were compared with the "Prerequisites for Tasty Water" and the "Standards for Tasty Water" devised for city water. The PET Bottled water varieties analyzed in this study-Seoksu, Icis, Bong Pyong, Soon Soo 100, Dong Won Saem Mul, GI JANG SOO and DIAMOND-showed the Water Index of Taste ≥ 2.0 and the Water Index of Health ≥ 5.2, which we classified as tasty/healthy water. SamDaSoo and NamiNeral can be classified as tasty water due to their values of the Water Index of Taste ≥ 2.0 and the Water Index of Health < 5.2. The South Korean PET bottled water studied here fulfills the "Water Index of Taste," "Water Index of Health," "Standard for Tasty Water" and "Prerequisites for Tasty Water" that Japanese people value for city water. We can conclude that bottled water which meets water quality requirements will be considered good-tasting by a majority of people.

Monitoring and Assessment of Youshui River Water Quality in Youyang

NASA Astrophysics Data System (ADS)

Wang, Xue-qin; Wen, Juan; Chen, Ping-hua; Liu, Na-na

2018-02-01

By monitoring the water quality of Youshui River from January 2016 to December 2016, according to the indicator grading and the assessment standard of water quality, the formulas for 3 types water quality indexes are established. These 3 types water quality indexes, the single indicator index Ai, single moment index Ak and the comprehensive water quality index A, were used to quantitatively evaluate the quality of single indicator, the water quality and the change of water quality with time. The results show that, both total phosphorus and fecal coliform indicators exceeded the standard, while the other 16 indicators measured up to the standard. The water quality index of Youshui River is 0.93 and the grade of water quality comprehensive assessment is level 2, which indicated that the water quality of Youshui River is good, and there is room for further improvement. To this end, several protection measures for Youshui River environmental management and pollution treatment are proposed.

Describing the spatio-temporal variability of vines and soil by satellite-based spectral indices: A case study in Apulia (South Italy)

NASA Astrophysics Data System (ADS)

Borgogno-Mondino, E.; Novello, V.; Lessio, A.; de Palma, L.

2018-06-01

A time series of Landsat 8 OLI (L8 OLI) multispectral images acquired between May 2013 and February 2016 were used to investigate vigour, vine and soil water content in a vineyard of Moscato Reale (syn. Moscato Bianco) sited in the Castel del Monte DOCG area. Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) were calculated and compared with vine midday stem water potential (ΨMDstem) and soil volume water content (VWC), to calibrate estimation models. Estimation models were calibrated using already existing ground observation datasets from previous ordinary vineyard management operations: ΨMDstem was measured at two different locations in vineyard at 6 different dates in summer 2014; VWC was continuously measured from June to October 2014 and from January to September 2015. Results showed that: a) vine stem water potential can be locally estimated with an accuracy ranging from ±0.046 (high vigour vines) to ±0.127 (low vigour vines) MPa; b) soil volume water content can be locally estimated with an accuracy of about ±1.7%. Medium resolution satellite imagery proved, therefore, to be effective, at vineyard level, to describe vigour, vine and soil water status and their seasonality. This is an important issue to focus on since, as Landsat 8 images are free, the entire process is economic enough to be consistent with cost and incoming of the farming system.

Observations of Typhoon Center by Using Satellite-derived Normalized Difference Convection Index

NASA Astrophysics Data System (ADS)

Liu, Chung-Chih; Chen, Chun-Hsu

2015-04-01

A technique involving differencing water vapor and infrared window channel brightness temperature values to identify and quantify intense convection in tropical cyclones using bispectral geostationary satellite imagery was proposed by Olander and Velden (2009). Rouse et al. (1974) calculated a normalized ratio of the near infrared and red bands and proposed an index called the normalized difference vegetation index. It was then used in many fields such as estimations of vegetation biomass, leaf area, the proportion of absorbed photosynthetically active radiation, etc. The present study used the spectral features of the IR1 and WV channels of the satellite to define a new index, the brightness temperature of the infrared window channel minus the brightness temperature of the water vapor channel divided by the brightness temperature of the infrared window channel plus the brightness temperature of the water vapor channel. The values obtained by this formula are called the Normalized Difference Convection Index (NDCI) values. The NDCI value is between -1 and 1. The NDCI value at WV = 0K is the highest, 1; while that at IR1 = 0K is the lowest, -1. In cases of a clear sky or atmosphere with thin cloud and dry air, NDCI values should be larger than 0. In cases of a convective cloud system, NDCI values should be lower than 0. In addition, the newly defined NDCI does show significant difference from simple difference of IR1-WV. For example, the NDCI value is -0.0017 at IR1=299K and WV=300K, while the NDCI value is -0.0033 at IR1=149K and WV=150K. The two times difference of NDCI values shows the features of clouds with NDCI value -0.0017 are quite different from those with NDCI value -0.0033. The former may be low level clouds, but the latter may be deep convections. However, the simple difference of IR1-WV cannot be used to distinguish the difference. The NDCI was applied to determine the centers of Typhoon Longwang (2005). The results showed that the two-dimensional NDCI analysis helped to identify positions of overshooting areas. In addition, because the NDCI values near a typhoon eye were rather significant, if a typhoon eye was formed, the NDCI cross-section analysis could help to confirm its position. When the center of a typhoon was covered by the high Anvils and Cirrus Layers, it could still be found qualitatively through the two-dimensional analysis. Keywords:Typhoon, Satellite imagery, Normalized Difference Convection Index

[Effects of combined application of water retention agent and organic fertilizer on physico-chemical properties of iron tailings.

PubMed

Li, Xiang; Zhang, Bao Juan; Li, Ji Quan; Li, Yu Ling; Li, Chen Guang

2017-02-01

In order to analyze the effects of combined application of water retention agent and orga-nic fertilizer on physico-chemical properties of iron tailings and to find the optimal proportion of water retention agent and organic fertilizer for the improvement of iron tailings, the experimental plots of the combination trials with 2 factors in 4 levels were designed in the iron tailings of Qian'an Shougang through investigating some indexes of physico-chemical properties such as bulk density, moisture capacity, porosity, pH and the contents of organic matter, nitrogen, phosphorus and potas-sium. The biomasses of Medicago sativa and Amorpha fruticosa planted in the experimental plots were measured to verify the improvement effects. 4 levels of super absorbent polymers (L·m -3 ) used in treatments were 0 (B 0 ), 10 (B 1 ), 50 (B 2 ), 100 (B 3 ), and 4 levels of organic fertilizer (kg·m -2 ) were 0(N 0 ), 2.25 (N 1 ), 11.24 (N 2 ), 22.49 (N 3 ). The improving effects of different treatments on physico-chemical properties of iron tailings were mainly reflected in the surface layer of 0-20 cm. All the tested indexes were significantly different from control (CK) in the layer of 0-20 cm. The improvement effects of organic fertilizer on physical and chemical properties of iron tai-lings were better than that of water retention agent. In the 0-20 cm layer, the bulk density, non-capillary porosity, organic matter, rapidly available phosphorus, and available potassium under all treatments of adding water retention agent individually were not significantly different from the CK, while significant difference was observed when the organic fertilizer was solely applied in B 0 N 2 and B 0 N 3 treatments. The improvement synergy effect of organic fertilizer and water retention agent was better than that of organic fertilizer or water retention agent, respectively. In 0-20 cm layer, all the indexes obtained from treatment B 3 N 3 performed best and were significantly different from the CK, which was the optimum for the improvement of iron tailings.

Water Quality Evaluation of PET Bottled Water by Mineral Balance in the Northeast Asian Region: A Case Study of South Korea

PubMed Central

Houri, Daisuke; Koo, Chung Mo

2015-01-01

Background The past few years have seen a demand for drinking water in contemporary society with a focus on safety and taste. Mineral water is now marketed as a popular commercial product and, partly due to health concerns, the production. Methods For the study, a comparison was carried out of water samples from 9 types of polyethylene terephthalate (PET) bottled water sold in South Korea as well as from tap water in the cities of Seoul and Chuncheon. These were compared with samples of Japanese PET bottled water in order to determine shared commonalities and identify individual characteristics. To evaluate water quality objectively, we quantified the elements contained in the water samples. Samples were assessed not with the usual sensory evaluation but with the evaluation approach advocated by Hashimoto et al. which employs the Water Index of Taste and the Water Index of Health. The levels of water quality obtained were compared with the “Prerequisites for Tasty Water” and the “Standards for Tasty Water” devised for city water. Results The PET Bottled water varieties analyzed in this study—Seoksu, Icis, Bong Pyong, Soon Soo 100, Dong Won Saem Mul, GI JANG SOO and DIAMOND—showed the Water Index of Taste ≥ 2.0 and the Water Index of Health ≥ 5.2, which we classified as tasty/healthy water. SamDaSoo and NamiNeral can be classified as tasty water due to their values of the Water Index of Taste ≥ 2.0 and the Water Index of Health < 5.2. Conclusion The South Korean PET bottled water studied here fulfills the “Water Index of Taste,” “Water Index of Health,” “Standard for Tasty Water” and “Prerequisites for Tasty Water” that Japanese people value for city water. We can conclude that bottled water which meets water quality requirements will be considered good-tasting by a majority of people. PMID:26538797

Numerical method based on transfer function for eliminating water vapor noise from terahertz spectra.

PubMed

Huang, Y; Sun, P; Zhang, Z; Jin, C

2017-07-10

Water vapor noise in the air affects the accuracy of optical parameters extracted from terahertz (THz) time-domain spectroscopy. In this paper, a numerical method was proposed to eliminate water vapor noise from the THz spectra. According to the Van Vleck-Weisskopf function and the linear absorption spectrum of water molecules in the HITRAN database, we simulated the water vapor absorption spectrum and real refractive index spectrum with a particular line width. The continuum effect of water vapor molecules was also considered. Theoretical transfer function of a different humidity was constructed through the theoretical calculation of the water vapor absorption coefficient and the real refractive index. The THz signal of the Lacidipine sample containing water vapor background noise in the continuous frequency domain of 0.5-1.8 THz was denoised by use of the method. The results show that the optical parameters extracted from the denoised signal are closer to the optical parameters in the dry nitrogen environment.

A human fecal contamination index for ranking impaired ...

EPA Pesticide Factsheets

Human fecal pollution of surface water remains a public health concern worldwide. As a result, there is a growing interest in the application of human-associated fecal source identification quantitative real-time PCR (qPCR) technologies for recreational water quality risk management. The transition from a research subject to a management tool requires the integration of standardized water sampling, laboratory, and data analysis procedures. In this study, a standardized HF183/BacR287 qPCR method was combined with a water sampling strategy and Bayesian data algorithm to establish a human fecal contamination index that can be used to rank impaired recreational water sites polluted with human waste. Stability and bias of index predictions were investigated under various parameters including siteswith different pollution levels, sampling period time range (1-15 weeks), and number of qPCR replicates per sample (2-14 replicates). Sensitivity analyses were conducted with simulated data sets (100 iterations) seeded with HF183/BacR287 qPCR laboratory measurements from water samples collected from three Southern California sites (588 qPCR measurements). Findings suggest that site ranking is feasible and that all parameters tested influence stability and bias in human fecal contamination indexscoring. Trends identified by sensitivity analyses will provide managers with the information needed to design and conduct field studies to rank impaired recreational water sites based

Current and future droughts in the Southeastern Mediterranean

NASA Astrophysics Data System (ADS)

Törnros, Tobias; Menzel, Lucas

2016-04-01

The southeastern Mediterranean region (i.e., Israel, Palestine, Jordan and neighboring countries) increasingly suffers significant water stress. The semi-arid to arid conditions with low precipitation amounts, high temperatures and strong interannual climate variability recurrently trigger drought conditions. However, the complex political situation, showing a low degree of mutual cooperation, favors an unsustainable use of water resources and no long-term, cross-boundary water management plan exists. In order to address the drought conditions under current and future climates in this region, the Standardized Precipitation-Evaporation Index (SPEI) was applied. In the first step, the SPEI was derived from spatially interpolated monthly precipitation and temperature data at multiple timescales: accumulated precipitation and monthly mean temperature were considered over a different number of consecutive months. To investigate the performance of the drought index, correlation analyses were conducted with simulated soil moisture and the Normalized Difference Vegetation Index (NDVI) obtained from remote sensing. A comparison with the Standardized Precipitation Index (SPI), i.e., a drought index that does not incorporate temperature, was also conducted. The results show that the choice of the SPEI/SPI timescale is crucial. In our study, the 6-month SPEI has the highest correlation with simulated soil moisture and best explains the interannual variation of the monthly NDVI. Although not extensively addressed, the SPI performs almost just as well and could be applied if temperature data are not available. In the second step, the 6-month SPEI was derived from three climate projections based on the IPCC emission scenario A1B. When comparing the period 2031-2060 with 1961-1990, it is shown that the percentage of time with moderate, severe and extreme drought conditions is projected to strongly increase for all scenarios. Since agriculture is by far the most water demanding sector in the region, the impact of drought on agriculture was addressed. For this, the irrigation water demand during certain drought years was simulated with a hydrological model on a spatial resolution of 1 km. A large increase in the demand for irrigation water was simulated, showing that the agricultural sector is expected to become even more vulnerable to drought in the future.

Ethanol-acetone pulping of wheat straw. Influence of the cooking and the beating of the pulps on the properties of the resulting paper sheets.

PubMed

Jiménez, L; Pérez, I; López, F; Ariza, J; Rodríguez, A

2002-06-01

The influence of independent variables in the pulping of wheat straw by use of an ethanol-acetone-water mixture [processing temperature and time, ethanol/(ethanol + acetone) value and (ethanol + acetone)/(ethanol + acetone + water) value] and of the number of PFI beating revolutions to which the pulp was subjected, on the properties of the resulting pulp (yield and Shopper-Riegler index) and of the paper sheets obtained from it (breaking length, stretch, burst index and tear index) was examined. By using a central composite factor design and the BMDP software suite, equations that relate each dependent variable to the different independent variables were obtained that reproduced the experimental results for the dependent variables with errors less than 30% at temperatures, times, ethanol/(ethanol + acetone) value, (ethanol + acetone)/(ethanol + acetone + water) value and numbers of PFI beating revolutions in the ranges 140-180 degrees C, 60-120 min, 25-75%, 35-75% and 0-1750, respectively. Using values of the independent variables over the variation ranges considered provided the following optimum values of the dependent variables: 78.17% (yield), 15.21 degrees SR (Shopper-Riegler index), 5265 m (breaking length), 1.94% (stretch), 2.53 kN/g (burst index) and 4.26 mN m2/g (tear index). Obtaining reasonably good paper sheets (with properties that differed by less than 15% from their optimum values except for the burst index, which was 28% lower) entailed using a temperature of 180 degrees C, an ethanol/(ethanol + acetone) value of 50%, an (ethanol + acetone)/(ethanol + acetone + water) value of 75%, a processing time of 60 min and a number of PFI beating revolutions of 1750. The yield was 32% lower under these conditions, however. A comparison of the results provided by ethanol, acetone and ethanol-acetone pulping revealed that the second and third process-which provided an increased yield were the best choices. On the other hand, if the pulp is to be refined, ethanol pulping is the process of choice.

Effective Use of Water and Increased Dry Matter Partitioned to Grain Contribute to Yield of Common Bean Improved for Drought Resistance

PubMed Central

Polania, Jose A.; Poschenrieder, Charlotte; Beebe, Stephen; Rao, Idupulapati M.

2016-01-01

Common bean (Phaseolus vulgaris L.) is the most important food legume in the diet of poor people in the tropics. Drought causes severe yield loss in this crop. Identification of traits associated with drought resistance contributes to improving the process of generating bean genotypes adapted to these conditions. Field studies were conducted at the International Center for Tropical Agriculture (CIAT), Palmira, Colombia, to determine the relationship between grain yield and different parameters such as effective use of water (EUW), canopy biomass, and dry partitioning indices (pod partitioning index, harvest index, and pod harvest index) in elite lines selected for drought resistance over the past decade. Carbon isotope discrimination (CID) was used for estimation of water use efficiency (WUE). The main objectives were: (i) to identify specific morpho-physiological traits that contribute to improved resistance to drought in lines developed over several cycles of breeding and that could be useful as selection criteria in breeding; and (ii) to identify genotypes with desirable traits that could serve as parents in the corresponding breeding programs. A set of 36 bean genotypes belonging to the Middle American gene pool were evaluated under field conditions with two levels of water supply (irrigated and drought) over two seasons. Eight bean lines (NCB 280, NCB 226, SEN 56, SCR 2, SCR 16, SMC 141, RCB 593, and BFS 67) were identified as resistant to drought stress. Resistance to terminal drought stress was positively associated with EUW combined with increased dry matter partitioned to pod and seed production and negatively associated with days to flowering and days to physiological maturity. Differences in genotypic response were observed between grain CID and grain yield under irrigated and drought stress. Based on phenotypic differences in CID, leaf stomatal conductance, canopy biomass, and grain yield under drought stress, the lines tested were classified into two groups, water savers and water spenders. Pod harvest index could be a useful selection criterion in breeding programs to select for drought resistance in common bean. PMID:27242861

Comparison of U.S. Geological Survey and Ohio Environmental Protection Agency fish-collection methods using the index of biotic integrity and modified index of well-being, 1996-97

USGS Publications Warehouse

Covert, S. Alex

2001-01-01

The U.S. Geological Survey (USGS) and Ohio Environmental Protection Agency (OEPA) collected data on fish from 10 stream sites in 1996 and 3 stream sites in 1997 as part of a comparative study of fish community assessment methods. The sites sampled represent a wide range of basin sizes (ranging from 132?6,330 square kilometers) and surrounding land-use types (urban, agricultural, and mixed). Each agency used its own fish-sampling protocol. Using the Index of Biotic Integrity and Modified Index of Well-Being, differences between data sets were tested for significance by means of the Wilcoxon signed-ranks test (a = 0.05). Results showed that the median of Index of Biotic Integrity differences between data sets was not significantly different from zero (p = 0.2521); however, the same statistical test showed the median differences in the Modified Index of Well-Being scores to be significantly different from zero (p = 0.0158). The differences observed in the Index of Biotic Integrity scores are likely due to natural variability, increased variability at sites with degraded water quality, differences in sampling methods, and low-end adjustments in the Index of Biotic Integrity calculation when fewer than 50 fish were collected. The Modified Index of Well-Being scores calculated by OEPA were significantly higher than those calculated by the USGS. This finding was attributed to the comparatively large numbers and biomass of fish collected by the OEPA. By combining the two indices and viewing them in terms of the percentage attainment of Ohio Warmwater Habitat criteria, the two agencies? data seemed comparable, although the Index of Biotic Integrity scores were more similar than the Modified Index of Well-Being scores.

Implications of non-sustainable agricultural water policies for the water-food nexus in large-scale irrigation systems: A remote sensing approach

NASA Astrophysics Data System (ADS)

Al Zayed, Islam Sabry; Elagib, Nadir Ahmed

2017-12-01

This study proposes a novel monitoring tool based on Satellite Remote Sensing (SRS) data to examine the status of water distribution and Water Use Efficiency (WUE) under changing water policies in large-scale and complex irrigation schemes. The aim is to improve our understanding of the water-food nexus in such schemes. With a special reference to the Gezira Irrigation Scheme (GeIS) in Sudan during the period 2000-2014, the tool devised herein is well suited for cases where validation data are absent. First, it introduces an index, referred to as the Crop Water Consumption Index (CWCI), to assess the efficiency of water policies. The index is defined as the ratio of actual evapotranspiration (ETa) over agricultural areas to total ETa for the whole scheme where ETa is estimated using the Simplified Surface Energy Balance model (SSEB). Second, the tool uses integrated Normalized Difference Vegetation Index (iNDVI), as a proxy for crop productivity, and ETa to assess the WUE. Third, the tool uses SSEB ETa and NDVI in an attempt to detect wastage of water. Four key results emerged from this research as follows: 1) the WUE has not improved despite the changing agricultural and water policies, 2) the seasonal ETa can be used to detect the drier areas of GeIS, i.e. areas with poor irrigation water supply, 3) the decreasing trends of CWCI, slope of iNDVI-ETa linear regression and iNDVI are indicative of inefficient utilization of irrigation water in the scheme, and 4) it is possible to use SSEB ETa and NDVI to identify channels with spillover problems and detect wastage of rainwater that is not used as a source for irrigation. In conclusion, the innovative tool developed herein has provided important information on the efficiency of a large-scale irrigation scheme to help rationalize laborious water management processes and increase productivity.

Relating seasonal patterns of the AVHRR vegetation index to simulated photosynthesis and transpiration of forests in different climates

NASA Technical Reports Server (NTRS)

Running, Steven W.; Nemani, Ramakrishna R.

1988-01-01

Weekly AVHRR Normalized Difference Vegetation Index (NDVI) values for 1983-1984 for seven sites of diverse climate in North America were correlated with results of an ecosystem simulation model of a hypothetical forest stand for the corresponding period at each site. The tendency of raw NDVI data to overpredict photosynthesis and transpiration on water limited sites was shown to be partially corrected by using an aridity index of annual radiation/annual precipitation. The results suggest that estimates of vegetation productivity using the global vegetation index are only accurate as annual integrations, unless unsubsampled local area coverage NDVI data can be tested against forest photosynthesis, transpiration and aboveground net primary production data measured at shorter time intervals.

Monitoring Coastal Marshes for Persistent Saltwater Intrusion

DTIC Science & Technology

2010-06-01

for the normalized difference indices (vegetation, soil, and water– NDVI , NDSI, and NDWI) for both MODIS and Landsat 5 and 7, referred to as the...Normalized Difference Index transformation [4]. The MODIS indices are 250 m ( NDVI ) and 500 m (NDWI and NDSI), and the Landsat indices are 30 m...indices are shown for two locations in Fig. 1 and Fig 2. Each figure shows the NDSI (soil), NDVI (vegetation), and NDWI (water) index as a function of

Microbiological quality of natural waters.

PubMed

Borrego, J J; Figueras, M J

1997-12-01

Several aspects of the microbiological quality of natural waters, especially recreational waters, have been reviewed. The importance of the water as a vehicle and/or a reservoir of human pathogenic microorganisms is also discussed. In addition, the concepts, types and techniques of microbial indicator and index microorganisms are established. The most important differences between faecal streptococci and enterococci have been discussed, defining the concept and species included. In addition, we have revised the main alternative indicators used to measure the water quality.

A spatial evaluation of global wildfire-water risks to human and natural systems.

PubMed

Robinne, François-Nicolas; Bladon, Kevin D; Miller, Carol; Parisien, Marc-André; Mathieu, Jérôme; Flannigan, Mike D

2018-01-01

The large mediatic coverage of recent massive wildfires across the world has emphasized the vulnerability of freshwater resources. The extensive hydrogeomorphic effects from a wildfire can impair the ability of watersheds to provide safe drinking water to downstream communities and high-quality water to maintain riverine ecosystem health. Safeguarding water use for human activities and ecosystems is required for sustainable development; however, no global assessment of wildfire impacts on water supply is currently available. Here, we provide the first global evaluation of wildfire risks to water security, in the form of a spatially explicit index. We adapted the Driving forces-Pressure-State-Impact-Response risk analysis framework to select a comprehensive set of indicators of fire activity and water availability, which we then aggregated to a single index of wildfire-water risk using a simple additive weighted model. Our results show that water security in many regions of the world is potentially vulnerable, regardless of socio-economic status. However, in developing countries, a critical component of the risk is the lack of socio-economic capability to respond to disasters. Our work highlights the importance of addressing wildfire-induced risks in the development of water security policies; the geographic differences in the components of the overall risk could help adapting those policies to different regional contexts. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Drought and water scarcity indicators: experience and operational applications in italian basins

NASA Astrophysics Data System (ADS)

Mazzanti, Bernardo; Checcucci, Gaia; Monacelli, Giuseppina; Puma, Francesco; Vezzani, Claudia

2013-04-01

In the framework of River Basin Managment Plans (RBMPs), according to the Water Framework Directive, prevention and mitigation of water scarcity and droughts are some of the most challenging tasks. In the last ten years Italy experienced the highest ever observed frequency of occurrence of drought/water scarcity events. As an example, the damages for the latest, country-wide drought event of summer 2012 exceeded one billion euros. On the other hand, according to the more recent reports on the risks of extreme events, there is evidence, providing a basis for medium confidence, that droughts will intensify over the coming century in southern Europe and in the Mediterranean region (IPCC 2012). Monitoring actions are necessary and extremely effective to "feel the pulse of the situation" about both natural availability and anthropic use of freshwater resources. In this context, referring to the Programmes of Measures of RBMPs, italian River Basin Authorities (RBA) are tackling the issue at different spatial scales, planning an operational use of different indicators, between theme the Water Exploitation Index (EEA, 2009) and some statistical indicators. In this context, Po and Arno River Basin authorities, with the support of ISPRA, are directly involved in the experimental application of some significant indicators combining climatic, hydrological and anthropic factors affecting water availability. Planning and operational experiences for the two main basins (Po and Arno) and for a list of smaller scale subbasins are presented, with a detailed description of data needs, range of application, spatial and temporal scale issues, and threshold definition. For each indicator, a critical analysis of strenghts and weaknesses (at data and response level) is reported, with particular regard to the feasibility of its use within water management and water planning actions at the river basin and district scale. Tests were carried out for the whole Po River and Northern Appennines districts, and for the basin of Arno, Trebbia and Oglio rivers, and included the following indicators: modified Water Exploitation Index (WEI+) calculated at annual and monthly scale (ETC/ICM, 2012); Standardized Precipitation Index (SPI); Standardized Runoff Index (SRI). The results confirmed the need for the analysis of the indicators different spatial and temporal scales to understand their meaning in the local regional context considered. It was clearly shown that sub-annual patterns of water availability and water use play a fundamental role in the indicators meaning, and should be considered in their operational application. References: IPCC, 2012 - Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation, 2012 ETC/ICM, 2012 - Vulnerability to Water Scarcity and Drought in Europe - Background thematic report for EEA water 2012 report, EEA/NSV/10/002

Remote sensing of water and nitrogen stress in broccoli

NASA Astrophysics Data System (ADS)

Elsheikha, Diael-Deen Mohamed

Remote sensing is being used in agriculture for crop management. Ground based remote sensing data acquisition system was used for collection of high spatial and temporal resolution data for irrigated broccoli crop. The system was composed of a small cart that ran back and forth on a rail system that was mounted on a linear move irrigation system. The cart was equipped with a sensor that had 4 discrete wavelengths; 550 nm, 660 nm, 720 nm, and 810 nm, and an infrared thermometer, all had 10 nm bandwidth. A global positioning system was used to indicate the cart position. The study consisted of two parts; the first was to evaluate remotely sensed reflectance and indices in broccoli during the growing season, and determine whether remotely sensed indices or standard deviation of indices can distinguish between nitrogen and water stress in broccoli, and the second part of the study was to evaluate remotely sensed indices and standard deviation of remotely sensed indices in broccoli during daily changes in solar zenith angle. Results indicated that nitrogen was detected using Ratio Vegetation index, RVI, Normalized Difference Vegetation Index, NDVI, Canopy Chlorophyll Concentration Index, CCCI, and also using the reflectance in the Near-Infrared, NIR, bands. The Red reflectance band capability of showing stress was not as clear as the previous indices and bands reflectance. The Canopy Chlorophyll Concentration Index, CCCI, was the most successful index. The Crop Water Stress Index was able to detect water stress but it was highly affected by the solar zenith angle change along the day.

National Coastal Condition Report IV Factsheet

EPA Pesticide Factsheets

Overall condition of the Nation’s coastal waters is fair. This rating is based on five indices of ecologicalcondition: water quality index, sediment quality index, benthic index, coastal habitat index, and fish tissue contaminants index.

Enhanced agricultural drought monitoring using a soil water anomaly-based drought index in south-west India

NASA Astrophysics Data System (ADS)

Hochstöger, Simon; Pfeil, Isabella; Amarnath, Giriraj; Pani, Peejush; Enenkel, Markus; Wagner, Wolfgang

2017-04-01

In India, agriculture accounts for roughly 17% of the GDP and employs around 50% of the total workforce. Especially in the western part of India, most of the agricultural fields are non-irrigated. Hence, agriculture is highly dependent on the monsoon in these areas. However, the absence of rainfall during the monsoon season increases the occurrence of drought periods, which is the main environmental factor affecting agricultural productivity. Rainfall is often not accessible to plants due to runoff or increased rates of evapotranspiration. Therefore, knowledge of the soil moisture state in the root zone of the soil is of great interest in the field of agricultural drought monitoring and operational decision-support. By introducing soil moisture, retrieved via active or passive microwave remote sensors, the gap between rainfall and the subsequent response of vegetation can be closed. Agricultural droughts are strongly influenced by a lack of water availability in the root zone of the soil, making anomalies of the Advanced Scatterometer (ASCAT) soil water index (SWI), representing the water content in lower soil layers, a suitable measure to estimate the water deficit in the soil. These anomalies describe the difference of the actual soil moisture value to the long-term average calculated for the same period. The objective of the study is to investigate the usability of soil moisture anomalies for developing an indicator that is based on critical thresholds, which finally results in a classification with different drought severity levels. In order to evaluate the performance of the drought index, it is compared to the Integrated Drought Severity Index (IDSI), which is developed at the International Water Management Institute in Colombo, Sri Lanka and to rainfall data from the Indian Meteorological Department (IMD). Overall, first analyses show a high potential of using SWI anomalies for agricultural drought monitoring. Most of the drought events detected by negative SWI anomalies correspond to IDSI drought events and also to reduced precipitation during that time.

A water marker monitored by satellites to predict seasonal endemic cholera.

PubMed

Jutla, Antarpreet; Akanda, Ali Shafqat; Huq, Anwar; Faruque, Abu Syed Golam; Colwell, Rita; Islam, Shafiqul

2013-01-01

The ability to predict an occurrence of cholera, a water-related disease, offers a significant public health advantage. Satellite based estimates of chlorophyll, a surrogate for plankton abundance, have been linked to cholera incidence. However, cholera bacteria can survive under a variety of coastal ecological conditions, thus constraining the predictive ability of the chlorophyll, since it provides only an estimate of greenness of seawater. Here, a new remote sensing based index is proposed: Satellite Water Marker (SWM), which estimates condition of coastal water, based on observed variability in the difference between blue (412 nm) and green (555 nm) wavelengths that can be related to seasonal cholera incidence. The index is bounded between physically separable wavelengths for relatively clear (blue) and turbid (green) water. Using SWM, prediction of cholera with reasonable accuracy, with at least two month in advance, can potentially be achieved in the endemic coastal regions.

Prediction of Floor Water Inrush: The Application of GIS-Based AHP Vulnerable Index Method to Donghuantuo Coal Mine, China

NASA Astrophysics Data System (ADS)

Wu, Qiang; Liu, Yuanzhang; Liu, Donghai; Zhou, Wanfang

2011-09-01

Floor water inrush represents a geohazard that can pose significant threat to safe operations for instance in coal mines in China and elsewhere. Its occurrence is controlled by many factors, and the processes are often not amenable to mathematical expressions. To evaluate the water inrush risk, the paper proposes the vulnerability index approach by coupling the analytic hierarchy process (AHP) and geographic information system (GIS). The detailed procedures of using this innovative approach are shown in a case study in China (Donghuantuo Coal Mine). The powerful spatial data analysis functions of GIS was used to establish the thematic layer of each of the six factors that control the water inrush, and the contribution weights of each factor was determined with the AHP method. The established AHP evaluation model was used to determine the threshold value for each risk level with a histogram of the water inrush vulnerability index. As a result, the mine area was divided into five regions with different vulnerability levels which served as general guidelines for the mine operations. The prediction results were further corroborated with the actual mining data, and the evaluation result is satisfactory.

Prediction of groundwater inrush into coal mines from aquifers underlying the coal seams in China: application of vulnerability index method to Zhangcun Coal Mine, China

NASA Astrophysics Data System (ADS)

Wu, Qiang; Zhou, Wanfang; Wang, Jinhua; Xie, Shuhan

2009-05-01

Groundwater inrush is a geohazard that can significantly impact safe operations of the coal mines in China. Its occurrence is controlled by many factors and processes are often not amenable to mathematical expressions. To evaluate the water inrush risk, Professor Wu and his colleagues have proposed the vulnerability index approach by coupling the artificial neural network (ANN) and geographic information system (GIS). The detailed procedures of using this innovative approach are shown in a case study. Firstly, the powerful spatial data analysis functions of GIS was used to establish the thematic layer of each of the main factors that control the water inrush, and then to choose the training sample on the thematic layer with the ANN-BP Arithmetic. Secondly, the ANN evaluation model of the water inrush was established to determine the threshold value for each risk level with a histogram of the water inrush vulnerability index. As a result, the mine area was divided into four regions with different vulnerability levels and they served as the general guidelines for the mine operations.

Use of porous materials to remove oil contaminants from water.

PubMed

Gołub, Adam; Piekutin, Janina

2018-06-15

The purpose of the research was to remove petroleum substances from water using porous materials. Birch bark, cork, glass wool and polyurethane foam were used for the study. The model solution was distilled water enriched with a mixture of petrol and diesel fuel in a volume ratio of 1:3. The model water used had 3 different concentrations of oil substances. The research included petroleum substances expressed as mineral oil index and aliphatic hydrocarbons, n-alkanes (from C7H16 to C38H78). The process of oil substances removal was carried out applying two methods: static and dynamic. Based on the research, it was found that materials the most effective in lowering the index of mineral oil and C7H16-C38H78 n-alkane concentrations were both birch bark and glass wool, both static and dynamic, while cork and polyurethane foam were less effective. In addition, concentration of C7H16-C38H78 n-alkanes was lowered in each measurement series to a greater extent than the mineral oil index. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluation of MODIS NDVI and NDWI for vegetation drought monitoring using Oklahoma Mesonet soil moisture data

USGS Publications Warehouse

Gu, Yingxin; Hunt, E.; Wardlow, B.; Basara, J.B.; Brown, Jesslyn F.; Verdin, J.P.

2008-01-01

The evaluation of the relationship between satellite-derived vegetation indices (normalized difference vegetation index and normalized difference water index) and soil moisture improves our understanding of how these indices respond to soil moisture fluctuations. Soil moisture deficits are ultimately tied to drought stress on plants. The diverse terrain and climate of Oklahoma, the extensive soil moisture network of the Oklahoma Mesonet, and satellite-derived indices from the Moderate Resolution Imaging Spectroradiometer (MODIS) provided an opportunity to study correlations between soil moisture and vegetation indices over the 2002-2006 growing seasons. Results showed that the correlation between both indices and the fractional water index (FWI) was highly dependent on land cover heterogeneity and soil type. Sites surrounded by relatively homogeneous vegetation cover with silt loam soils had the highest correlation between the FWI and both vegetation-related indices (r???0.73), while sites with heterogeneous vegetation cover and loam soils had the lowest correlation (r???0.22). Copyright 2008 by the American Geophysical Union.

Goos-Hänchen effect in semiconductor metamaterial waveguide and its application as a biosensor

NASA Astrophysics Data System (ADS)

Tang, Tingting; Li, Chaoyang; Luo, Li; Zhang, Yanfen; Li, Jie

2016-06-01

We investigate Goos-Hänchen (GH) effect in a prism waveguide coupling structure with semiconductor metamaterial (SMM) of ZnGaO/ZnO multilayer and explore the possibility as a biosensor. The GH effect in three different waveguides and their performances as a refractive index sensor to detect glycerol concentration in water are analyzed. The SMM brings a periodic property of GH shift peaks which is not found in other waveguides. It is also verified that setting coupling layer of the prism waveguide coupling structure as sensing area is an effective method to significantly increase the sensitivity to refractive index variation. A schematic diagram for the biosensor configuration is designed, and the sensitivity distribution for different glycerol water index is given. Calculation results show that in the proposed biosensor the maximum sensitivity reaches 3.2 × 106 μm/RIU and resolution reaches 1.6 × 10-7 (around 1.33306) with high sensitive position sensitive detector.

Projection pursuit water quality evaluation model based on chicken swam algorithm

NASA Astrophysics Data System (ADS)

Hu, Zhe

2018-03-01

In view of the uncertainty and ambiguity of each index in water quality evaluation, in order to solve the incompatibility of evaluation results of individual water quality indexes, a projection pursuit model based on chicken swam algorithm is proposed. The projection index function which can reflect the water quality condition is constructed, the chicken group algorithm (CSA) is introduced, the projection index function is optimized, the best projection direction of the projection index function is sought, and the best projection value is obtained to realize the water quality evaluation. The comparison between this method and other methods shows that it is reasonable and feasible to provide decision-making basis for water pollution control in the basin.

Role of geospatial technology in identifying natural habitat of malarial vectors in South Andaman, India.

PubMed

Shankar, Shiva; Agrawal, Deepak Kumar

2016-03-01

Malaria is a serious disease which has repeatedly threatened Andaman, an island territory of India. Uncharted dense vegetation and inaccessibility are the salient features of the area and the major areas are covered by remotely sensed data to identify the malaria vector's natural habitat. The present investigation appraises the role of geospatial technologies in identifying the natural habitat of malarial vectors. The base map was prepared from Survey of India's toposheets, the landuse map was prepared from indices techniques like normalised difference vegetation index (NDVI), normalised difference water index (NDWI), modified normalised difference water index (MNDWI), normalised difference pond index (NDPI), and normalized difference turbidity index (NDTI) in conjugation with visual interpretation. The soil moisture content map was reproduced from the soil atlas of Andaman and Nicobar Islands followed by generation of an aspect profile from ASTER-GDEM satellite data. Both the landuse map and aspect profile were validated for accuracy in the field. A weighted overlay analysis of the classes like landuse, soil moisture and aspect profile of the study area resulted in identification of the potential natural habitat map of malaria vector surrounding the areas of Tushnabad, Garacharma, Manglutan, Chouldari, Ferrargunj and Wimberlygunj hamlets. The natural habitat of malaria vector indicated that Tushnabad, Garacharma, Manglutan, Chouldari, Ferrargunj and Wimberlygunj hamlets are within the proximity of 2.5 km from the prime habitat location with more number of malaria positive cases. Also these hamlets are surrounded by dense evergreen forest and the land surface is draped by clay loam and clay soil texture exhibiting high soil moisture content warranting high rates of survival and proliferation of the vector ensuring resurgence of malaria every year. It is thus concluded that application of geospatial technologies plays an important role in identifying the natural habitat of malaria vector.

Preparation and characterization of starch-based loose-fill packaging foams

NASA Astrophysics Data System (ADS)

Fang, Qi

Regular and waxy corn starches were blended in various ratios with biodegradable polymers including polylactic acid (PLA), Eastar Bio Copolyester 14766 (EBC) and Mater-Bi ZF03U (MBI) and extruded with a C. W. Brabender laboratory twin screw extruder using a 3-mm die nozzle at 150°C and 150 rev/min. Physical characteristics including radial expansion, unit density and bulk density and water solubility index, water absorption characteristics, mechanical properties including compressibility, Young's modulus, spring index, bulk compressibility and bulk spring index and abrasion resistance were investigated as affected by the ingredient formulations, i.e. type of polymers, type of starches, polymer to starch ratio and starch moisture content. A completely randomized factorial blocking experimental design was used. Fifty-four treatments resulted. Each treatment was replicated three times. SAS statistical software package was used to analyze the data. Foams made of waxy starch had better radial expansion, lower unit density and bulk density than did foams made of regular starch. Regular starch foams had significantly lower water solubility index than did the waxy starch foams. PLA-starch foams had the lowest compressibility and Young's modulus. MBI-starch foams were the most rigid. All foams had excellent spring indices and bulk spring indices which were comparable to the spring index of commercial expanded polystyrene foam. Correlations were established between the foam mechanical properties and the physical characteristics. Foam compressibility and Young's modulus decreased as increases in radial expansion and decreases in unit and bulk densities. Their relationships were modeled with power law equations. No correlation was observed between spring index and bulk spring index and foam physical characteristics. MBI-starch foams had the highest equilibrium moisture content. EBC-starch and PLA-starch foams had similar water absorption characteristics. No significant difference existed in water absorption characteristics between foams made of regular and waxy starches. Empirical models were developed to correlate foam water absorption characteristics with relative humidity and polymer content. The developed models fit the data well with relatively small standard errors and uniformly scattered residual plots. Foams with higher polymer content had better abrasion resistance than did foams with lower polymer content.

MRI pallidal signal in children exposed to manganese in drinking water.

PubMed

Dion, Laurie-Anne; Bouchard, Maryse F; Sauvé, Sébastien; Barbeau, Benoit; Tucholka, Alan; Major, Philipe; Gilbert, Guillaume; Mergler, Donna; Saint-Amour, Dave

2016-03-01

Manganese (Mn) can have neurotoxic effects upon overexposure. We previously reported poorer cognitive and motor development in children exposed to Mn through drinking water, suggesting possible neurotoxic effects from Mn in water. Hyperintensity in the globus pallidus (GP) on T1-weighted magnetic resonance imaging (MRI) indicates excessive brain Mn accumulation. Previous studies have reported GP hyperintensity related to Mn exposure in occupationally exposed individuals. However, no study has used MRI in children exposed to Mn in drinking water and who show no sign of overt intoxication. To examine MRI signal intensity in the GP in children exposed to contrasted levels of Mn in drinking water. We enrolled 13 children exposed to low Mn concentration in water and 10 children (ages 9-15 years) with high concentration (median of 1 and 145μg/L, respectively). We calculated three MRI T1 indexes: (i) standard pallidal index (PI) using frontal white matter as reference; (ii) PI using pericranial muscles as reference; and (iii) T1 relaxation time. Each MRI index was compared between exposure groups, and with respect to the estimated Mn intake from water consumption. The standard PI did not differ between Mn-exposure groups. However, children in the group with high water-Mn concentration had significantly lower pericranial muscles PI than those with lower exposure and, accordingly, higher T1 relaxation time. Mn intake from water consumption was not correlated with the standard PI, but was significantly related to the pericranial muscles PI and T1 relaxation time. Motor performance was significantly lower in the high-exposure group. We observed lower signal intensity in the GP of children with higher exposure to Mn from drinking water. This result stands in contrast to previous MRI reports showing GP hyperintensity with greater Mn exposure. Differences in exposure pathways are discussed as a potential explanation for this discrepancy. Copyright © 2016 Elsevier Inc. All rights reserved.

Setting of index system of environmental and economic accounting of water

NASA Astrophysics Data System (ADS)

Tan, Yarong

2017-10-01

To realize the quality advancement of integrated water management in China, a scientific and perfect index system of environmental and economic accounting should be built. At present, the water shortage in China becomes increasingly serious, which further highlights the importance of efficient water management and improving the index system of water economic accounting. Based on the internal structure of the new statistical method of environmental and economic accounting, this paper focuses on analyzing and discussing the index system which it should have.

A new index for identifying socioeconomic drought events under climate change over the East River basin in China

NASA Astrophysics Data System (ADS)

Shi, H.; Chen, J.; Wang, K.; Niu, J.

2017-12-01

Drought, which means severe water deficiencies, is a complex natural hazard that may have destructive damages on societal properties and lives. Generally, socioeconomic drought occurs when the water resources systems cannot meet the water demands due to a weather-related shortfall in water supply to societies. This paper aims to propose a new index (i.e., socioeconomic drought index (SEDI)) for identifying socioeconomic drought events on different levels (i.e., slight, moderate, severe and extreme) under climate change through considering the gap between water supply and demand. First, the minimum in-stream water requirement (MWR) is determined through comprehensively considering the requirements of water quality, ecology, navigation and water supply. Second, according to the monthly water deficit calculated as the monthly streamflow data minus the MWR, drought month can be identified. Third, according to the cumulative water deficit derived from the monthly water deficit, drought duration (i.e., the number of continuous drought months) can be detected. Fourth, the SEDI of each socioeconomic drought event can be calculated through integrating the impacts of the cumulative water deficit and drought duration. The study area is the East River basin in South China, and the impact of a multi-year reservoir (i.e., the Xinfengjiang Reservoir) on drought is also analyzed. For historical and future drought analysis, it is concluded that the proposed SEDI is feasible to identify socioeconomic drought events. The results show that a number of socioeconomic drought events (including some extreme ones) may occur during 2020-2099, and the appropriate reservoir operation can significantly ease such situation.

The trade of virtual water: do property rights matter?

NASA Astrophysics Data System (ADS)

Xu, Ankai

2016-04-01

My paper examines the determinants of the virtual water trade - embodied in the trade of agriculture products - by estimating a structural gravity model. In particular, it tests the relationship between property rights and the export of water-intensive agricultural products based on water footprint data in Mekonnen and Hoekstra (2011, 2012). Using two different measures of property rights protection, I show that countries with weaker property rights have an apparent comparative advantage in the trade of water-intensive products. After controlling for the economic size, natural resource endowments, and possible effects of reverse causality, the trade flow of virtual water is negatively and significantly correlated with the property rights index of the exporting country. Holding other factors constant, one point increase in the property rights index of a country is associated with a 24% - 36% decrease in its virtual water export, whereas a 1% increase in the natural resource protection index of a country is associated with a 16% decrease in its virtual water export. This paper is the first empirical work that tests the relationship between property rights and trade of water-intensive products, offering a new perceptive in the debate of virtual water trade. The findings provide a possible explanation on the paradoxical evidence that some countries with scarce water resources export water-intensive products. The result is important not only in terms of its theoretical relevance, but also its policy implications. As prescribed by the model of trade and property rights, when countries with weaker property rights open to international trade, they are more likely to over-exploit and thus expedite the depletion of natural resources.

The water quality and Cultivant enrichment potency of pond based on saprobic index at north coastal waters of Central Java, Indonesia

NASA Astrophysics Data System (ADS)

Hidayat, Jafron W.

2018-05-01

Central Java is one of many areas which has long coastline, especially in the Northern Coast of Java Island. Intertidal activities occurred at this area may affect the transport of material and energy from surroundings. Cultivation activity supplies many inputs, i.e. feeds, chemicals (vitamin and mineral), including pollutants from feces and unconsumed feeds that affects the environment. One of water management is done through bioremediation by using vegetative agents (soft rehabilitation), such as seaweed and mangrove stands. The implementation of soft rehabilitation is highly depend on the existing environmental conditions of the ponds and surrounding waters. Therefore, it is very important to identify the condition of those waters first. The purpose of this study is to identify the quality of waters in the north coast of Central Java. Besides, it is also to analyze the potency of enriching cultivated commodity (cultivant), as well as a soft remediation mechanism using seaweed. The study was conducted in the coastal areas of Central Java, mainly to the locations commonly practicing cultivation in the pond waters; namely Brebes, Pemalang, Semarang, Demak, Pati and Jepara. Data were taken by sampling at least at 3 different sites as repetition, included ponds, public irrigations and coastline waters. The water sample was taken as much as 30 lt and filtered using plankton net no 25. Biodiversity of Shannon-Wiener Index (H'), evenness index (e) and Saprobic Index were used to analyze the plankton data. Result showed that plankton diversity in Central Java coasts were varied generally between 10 – 28 species. The most widely found species were Oscillatoria sp, Rhizosolenia styliformes, Surirella sp and Lyngbia conferoides. The diversity index varied from 1.83 to 2.9 with the stability status were between small to medium. The saprobic index showed a value between 0.33 up to 2.27; which indicated very small up to lightly contaminated status. The biggest stability disturbance was found in Batangan (Pati) water, especially because the existence of salt production practice in the pond during dry season. The optimum polyculture practice was found in Brebes, since this water was still suitable to support aquaculture in multitrophic basis, so called IMTA (Integrated Multitrophic Aquaculture). In general, the other pantura waters were still liable to be enriched with other cultivants, including seaweed which is also economically valuable (as a commodity) and also ecologically functional in controlling turbidity and contamination.

Study of water masses variability in the Mediterranean Sea using in-situ data / NEMO-Med12 model.

NASA Astrophysics Data System (ADS)

Margirier, Félix; Testor, Pierre; Mortier, Laurent; Arsouze, Thomas; Bosse, Anthony; Houpert, Loic; Hayes, Dan

2016-04-01

In the past 10 years, numerous observation programs in the Mediterranean deployed autonomous platforms (moorings, argo floats, gliders) and thus considerably increased the number of in-situ observations and the data coverage. In this study, we analyse time series built with profile data on interannual scales. Sorting data in regional boxes, we follow the evolution of different water masses in the basin and generate indexes to characterize their evolution. We then put those indexes in relation with external (atmospheric) forcings and present an intercomparison with the NEMO-Med12 model to estimate both the skill of the model and the relevance of the data-sampling in reproducing the evolution of water masses properties.

Design and Application of Drought Indexes in Highly Regulated Mediterranean Water Systems

NASA Astrophysics Data System (ADS)

Castelletti, A.; Zaniolo, M.; Giuliani, M.

2017-12-01

Costs of drought are progressively increasing due to the undergoing alteration of hydro-meteorological regimes induced by climate change. Although drought management is largely studied in the literature, most of the traditional drought indexes fail in detecting critical events in highly regulated systems, which generally rely on ad-hoc formulations and cannot be generalized to different context. In this study, we contribute a novel framework for the design of a basin-customized drought index. This index represents a surrogate of the state of the basin and is computed by combining the available information about the water available in the system to reproduce a representative target variable for the drought condition of the basin (e.g., water deficit). To select the relevant variables and combinatione thereof, we use an advanced feature extraction algorithm called Wrapper for Quasi Equally Informative Subset Selection (W-QEISS). W-QEISS relies on a multi-objective evolutionary algorithm to find Pareto-efficient subsets of variables by maximizing the wrapper accuracy, minimizing the number of selected variables, and optimizing relevance and redundancy of the subset. The accuracy objective is evaluated trough the calibration of an extreme learning machine of the water deficit for each candidate subset of variables, with the index selected from the resulting solutions identifying a suitable compromise between accuracy, cardinality, relevance, and redundancy. The approach is tested on Lake Como, Italy, a regulated lake mainly operated for irrigation supply. In the absence of an institutional drought monitoring system, we constructed the combined index using all the hydrological variables from the existing monitoring system as well as common drought indicators at multiple time aggregations. The soil moisture deficit in the root zone computed by a distributed-parameter water balance model of the agricultural districts is used as target variable. Numerical results show that our combined drought index succesfully reproduces the deficit. The index represents a valuable information for supporting appropriate drought management strategies, including the possibility of directly informing the lake operations about the drought conditions and improve the overall reliability of the irrigation supply system.

A novel approach in water quality assessment based on fuzzy logic.

PubMed

Gharibi, Hamed; Mahvi, Amir Hossein; Nabizadeh, Ramin; Arabalibeik, Hossein; Yunesian, Masud; Sowlat, Mohammad Hossein

2012-12-15

The present work aimed at developing a novel water quality index based on fuzzy logic, that is, a comprehensive artificial intelligence (AI) approach to the development of environmental indices for routine assessment of surface water quality, particularly for human drinking purposes. Twenty parameters were included based on their critical importance for the overall water quality and their potential impact on human health. To assess the performance of the proposed index under actual conditions, a case study was conducted at Mamloo dam, Iran, employing water quality data of four sampling stations in the water basin of the dam from 2006 to 2009. Results of this study indicated that the general quality of water in all the sampling stations over all the years of the study period is fairly low (yearly averages are usually in the range of 45-55). According to the results of ANOVA test, water quality did not significantly change over time in any of the sampling stations (P > 0.05). In addition, comparison of the outputs of the fuzzy-based proposed index proposed with those of the NSF water quality index (the WQI) and Canadian Water Quality Index (CWQI) showed similar results and were sensitive to changes in the level of water quality parameters. However, the index proposed by the present study produced a more stringent outputs compared to the WQI and CWQI. Results of the sensitivity analysis suggested that the index is robust against the changes in the rules. In conclusion, the proposed index seems to produce accurate and reliable results and can therefore be used as a comprehensive tool for water quality assessment, especially for the analysis of human drinking water. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Elaboration of instant corn flour by hydrothermal process I].

PubMed

Martínez B, F; el-Dahs, A A

1993-12-01

The objective of this research was to investigate a simplified hydrothermal process for the production of instant corn flour and evaluate some variables that affected the degree of gelatinization of corn flour, and evaluate some technological characteristics of the flour. The use of grits of lesser particle diameter and increasing temperature of the soaking water resulted in an increase in the rate of absorption of water of grits, permitting a reduction of soaking time necessary for the process. The instant corn flour prepared by the hydrothermal process using corn grits soaked in water at room temperature (28-30 degrees C) for 5 hours and steaming for 1 minute at 118 degrees C presented characteristics of viscosity, water absorption index and water solubility index similar to that of flours prepared with grits soaked in water at a temperature higher tan room temperature and different steaming time (5 and 15 minutes). The characteristics of color and shelf life of corn flour were improved with the hydrothermal process.

Rewarming index of the lower leg assessed by infrared thermography in adolescents with type 1 diabetes mellitus.

PubMed

Zotter, Heinz; Kerbl, Reinhold; Gallistl, Siegfried; Nitsche, Hilde; Borkenstein, Martin

2003-12-01

The aim of this study was to determine whether infrared thermography before and after challenge of the lower leg in cold water may be a useful tool to detect abnormalities in skin blood flow in adolescent asymptomatic patients with type 1 diabetes mellitus (DM1) and to assess the optimal setting of skin temperature measurements. Twenty-five adolescents (10 female, 15 male, mean age 21.2 +/- 6.2 years, body mass index [BMI] 23.0 +/- 2.1 kg/m2) with a duration of DMI of 13.8 +/- 5.4 years and mean HbA1c levels 8.5 +/- 1.3% were compared to age- and sex-matched controls (BMI 22.9 +/- 2.2 kg/m2). Seven defined sites of the lower leg were assessed by infrared thermography before and for 10 min after exposure of the leg to 14 degrees C cold water. As skin temperature before exposure to cold water differs from individual to individual and basal temperature was significantly warmer in patients at the tip of the first (p < 0.05) and fifth (p < 0.05) toe, the rewarming index was calculated in order to compare data. Rewarming indexes of skin temperature during the whole measurement procedure (0-10 min) were significantly lower at the tip of the first (p < 0.05) and fifth (p < 0.01) toes and from minute 2-10 also at the inner ankle (p < 0.05) in patients compared to healthy controls. Rewarming indexes of the other four sites were not significantly different between patients and controls. Infrared thermography of the lower leg after cold water exposure is an easily applicable method and a useful tool to detect abnormalities of skin blood flow in adolescents with DM1 especially at the tips of the first and fifth toes and the inner ankle.

Applying a water quality index model to assess the water quality of the major rivers in the Kathmandu Valley, Nepal.

PubMed

Regmi, Ram Krishna; Mishra, Binaya Kumar; Masago, Yoshifumi; Luo, Pingping; Toyozumi-Kojima, Asako; Jalilov, Shokhrukh-Mirzo

2017-08-01

Human activities during recent decades have led to increased degradation of the river water environment in South Asia. This degradation has led to concerns for the populations of the major cities of Nepal, including those of the Kathmandu Valley. The deterioration of the rivers in the valley is directly linked to the prevalence of poor sanitary conditions, as well as the presence of industries that discharge their effluents into the river. This study aims to investigate the water quality aspect for the aquatic ecosystems and recreation of the major rivers in the Kathmandu Valley using the Canadian Council of Ministers of the Environment water quality index (CCME WQI). Ten physicochemical parameters were used to determine the CCME WQI at 20 different sampling locations. Analysis of the data indicated that the water quality in rural areas ranges from excellent to good, whereas in denser settlements and core urban areas, the water quality is poor. The study results are expected to provide policy-makers with valuable information related to the use of river water by local people in the study area.

The use of biotic and abiotic components of Red Sea coastal areas as indicators of ecosystem health.

PubMed

Omar, Wael A; Saleh, Yousef S; Marie, Mohamed-Assem S

2016-03-01

A biomonitoring study was conducted using some biotic (Pomadasys hasta and Lutjanus russellii fish) and abiotic (water and sediment) components of the Red Sea coast of Hodeida, Yemen Republic along two polluted sites (Al-Dawar beach and Urj village) in comparison to a reference site (Al-Nukhailah beach). The studied fish biomarkers included hepatosomatic index (HSI), condition factor (K), scaled mass index (SMI), catalase, glutathione-S-transferase (GST), malondialdehyde (MDA), total protein and albumin. In addition, metals (Fe, Cu, Zn, Pb and Cd) concentrations in water and sediment were measured and sediment pollution assessment was carried out using contamination factor (CF), geoaccumulation index (Igeo), pollution load index (PLI) and enrichment factor (EF). The studied metals concentration in water and sediment samples showed significant increase among the polluted sites in comparison to the reference site. Sediment pollution assessment generally confirmed that Urj village was the most contaminated site followed by Al-Dawar beach. Catalase, GST and MDA proved to be the most responsive biomarkers with increased values of GST and MDA at sites influenced by agricultural, urban and industrial activities while catalase, HSI, K, SMI, total protein and albumin showed the opposite trend. This study recommends monitoring of sediment Igeo and EF values as well as SMI, catalase, GST and MDA as sensitive indicators of different anthropogenic activities and their effects on aquatic ecosystems under complex and different gradients of metal pollution. In addition, P. hasta proved to be more sensitive towards the detected pollution condition.

Physical and functional properties of arrowroot starch extrudates.

PubMed

Jyothi, A N; Sheriff, J T; Sajeev, M S

2009-03-01

Arrowroot starch, a commercially underexploited tuber starch but having potential digestive and medicinal properties, has been subjected to extrusion cooking using a single screw food extruder. Different levels of feed moisture (12%, 14%, and 16%) and extrusion temperatures (140, 150, 160, 170, 180, and 190 degrees C) were used for extrusion. The physical properties--bulk density, true density, porosity, and expansion ratio; functional properties such as water absorption index, water solubility index, oil absorption index, pasting, rheological, and textural properties; and in vitro enzyme digestibility of the extrudates were determined. The expansion ratio of the extrudates ranged from 3.22 to 6.09. The water absorption index (6.52 to 8.85 g gel/g dry sample), water solubility index (15.92% to 41.31%), and oil absorption index (0.50 to 1.70 g/g) were higher for the extrudates in comparison to native starch (1.81 g gel/g dry sample, 1.16% and 0.60 g/g, respectively). The rheological properties, storage modulus, and loss modulus of the gelatinized powdered extrudates were significantly lower (P < 0.05) and these behaved like solutions rather than a paste or a gel. Hardness and toughness were more for the samples extruded at higher feed moisture and lower extrusion temperature, whereas snap force and energy were higher at lower feed moisture and temperature. There was a significant decrease in the percentage digestibility of arrowroot starch (30.07% after 30 min of incubation with the enzyme) after extrusion (25.27% to 30.56%). Extrusion cooking of arrowroot starch resulted in products with very good expansion, color, and lower digestibility, which can be exploited for its potential use as a snack food.

The dynamics of soil aggregate breakdown in water in response to landuse as measured with laser diffraction technique

NASA Astrophysics Data System (ADS)

Oyedele, D. J.; Pini, R.; Sparvoli, E.; Scatena, M.

2012-04-01

The Mastersizer 2000G (Malvern Instruments) Diffraction Instrument was used to assess and quantify the breakdown of soil aggregates and compute wet aggregate stability indices. The study was aimed at evolving a novel rapid method of determining soil aggregate stability. Bulk surface (0-15 cm) soil samples were collected under 5 different land uses in the Teaching and Resrach Farm of Obafemi Awolowo University, Ile-Ife, Nigeria. About 0.5g of the soils aggregates (0.5 -1 mm diameter) were evaluated in the laser diffractometer with the stirrer operated at 500 rpm and the pump at 1800 rpm. The different size aggregates and particles of sand silt and clay were quantified periodically. Water stable aggregates greater than 250 µm (WSA>250), water stable aggregates less than 250 µm (WSA<250), water dispersible clay index (WDI), and mean volume diameter (MVD) among others were computed from the laser diffraction data. The values were compared with the classical Yoder wet sieving technique. The WSA>250 was significantly higher on the soils under Forest (FR), Cacao (CC), Teak (TK) and Oil Palm (OP) plantations, while it was significantly lowest under no-tillage (NT) and continuous cultivation (CT). The pasture (PD) was not significantly different from either the cultivated and the non-cultivated soils. Conversely, the WSA<250 and water dispersible clay index was highest in the cultivated soils (CT and NT) and lowest in the non-cultivated soils (FR, TK, CC and OP) while the PD was in-between. The MVD also followed a similar trend as the WSA>250. The wet sieving water stable aggregates index (WSI>250) was significantly correlated with WSA>250 (r = 0.75), MVD (r = 0.75), WDI (r = -0.68) and WSA<250 (r = - 0.73). All the laser diffraction measured aggregation indices were significantly correlated with the organic matter contents of the soils. Thus the laser diffraction promises a rapid and comprehensive method of evaluation of soil aggregate stability.

Remote sensing technologies applied to the irrigation water management on a golf course

NASA Astrophysics Data System (ADS)

Pedras, Celestina; Lança, Rui; Martins, Fernando; Soares, Cristina; Guerrero, Carlos; Paixão, Helena

2015-04-01

An adequate irrigation water management in a golf course is a complex task that depends upon climate (multiple microclimates) and land cover (where crops differ in morphology, physiology, plant density, sensitivity to water stress, etc.). These factors change both in time and space on a landscape. A direct measurement provides localized values of the evapotranspiration and climate conditions. Therefore this is not a practical or economical methodology for large-scale use due to spatial and temporal variability of vegetation, soils, and irrigation management strategies. Remote sensing technology combines large scale with ground measurement of vegetation indexes. These indexes are mathematical combinations of different spectral bands mostly in the visible and near infrared regions of the electromagnetic spectrum. They represent the measures of vegetation activity that vary not only with the seasonal variability of green foliage, but also across space, thus they are suitable for detecting spatial landscape variability. The spectral vegetation indexes may enhance irrigation management through the information contained in spectral reflectance data. This study was carried out on the 18th fairway of the Royal Golf Course, Vale do Lobo, Portugal, and it aims to establish the relationship between direct measurements and vegetation indexes. For that it is required (1) to characterize the soil and climatic conditions, (2) to assessment of the irrigation system, (3) to estimate the evapotranspiration (4) and to calculate the vegetation indices. The vegetation indices were determined with basis on spectral bands red, green and blue, RGB, and near Infrared, NIR, obtained from the analysis of images acquired from a unpiloted aerial vehicle, UAV, platform. The measurements of reference evapotranspiration (ETo) were obtained from two meteorological stations located in the study area. The landscape evapotranspiration, ETL, was determined in the fairway with multiple microclimates and managed stress. The ETL was obtained thru the use of mobile reference ET stations and also by the development of the surface renewal (SR) measurement technique. The sprinkler irrigation system installed was evaluated according to the methodology described by ASAE. The Normalized Difference Vegetation Index, NDVI, and Visible atmospherically Resistant Index, VARI, are confronted with the direct localized measurements. The NDVI is the most used indicator to assess the vigor status of the vegetation. However, this index depends of the use of NIR bands which demands quite expensive sensors. The use vegetation indexes obtained by sensors that collect data in the visible wavelength, such as VARI is less expensive and allow the vegetative vigor evaluation with a similar rigor. The information of vegetation indices is crossed with edafoclimatic data obtained in situ, in order to improve the irrigation water management based on aerial imagery.

Application of the BMWP-Costa Rica biotic index in aquatic biomonitoring: sensitivity to collection method and sampling intensity.

PubMed

Gutiérrez-Fonseca, Pablo E; Lorion, Christopher M

2014-04-01

The use of aquatic macroinvertebrates as bio-indicators in water quality studies has increased considerably over the last decade in Costa Rica, and standard biomonitoring methods have now been formulated at the national level. Nevertheless, questions remain about the effectiveness of different methods of sampling freshwater benthic assemblages, and how sampling intensity may influence biomonitoring results. In this study, we compared the results of qualitative sampling using commonly applied methods with a more intensive quantitative approach at 12 sites in small, lowland streams on the southern Caribbean slope of Costa Rica. Qualitative samples were collected following the official protocol using a strainer during a set time period and macroinvertebrates were field-picked. Quantitative sampling involved collecting ten replicate Surber samples and picking out macroinvertebrates in the laboratory with a stereomicroscope. The strainer sampling method consistently yielded fewer individuals and families than quantitative samples. As a result, site scores calculated using the Biological Monitoring Working Party-Costa Rica (BMWP-CR) biotic index often differed greatly depending on the sampling method. Site water quality classifications using the BMWP-CR index differed between the two sampling methods for 11 of the 12 sites in 2005, and for 9 of the 12 sites in 2006. Sampling intensity clearly had a strong influence on BMWP-CR index scores, as well as perceived differences between reference and impacted sites. Achieving reliable and consistent biomonitoring results for lowland Costa Rican streams may demand intensive sampling and requires careful consideration of sampling methods.

A novel two-stage evaluation system based on a Group-G1 approach to identify appropriate emergency treatment technology schemes in sudden water source pollution accidents.

PubMed

Qu, Jianhua; Meng, Xianlin; Hu, Qi; You, Hong

2016-02-01

Sudden water source pollution resulting from hazardous materials has gradually become a major threat to the safety of the urban water supply. Over the past years, various treatment techniques have been proposed for the removal of the pollutants to minimize the threat of such pollutions. Given the diversity of techniques available, the current challenge is how to scientifically select the most desirable alternative for different threat degrees. Therefore, a novel two-stage evaluation system was developed based on a circulation-correction improved Group-G1 method to determine the optimal emergency treatment technology scheme, considering the areas of contaminant elimination in both drinking water sources and water treatment plants. In stage 1, the threat degree caused by the pollution was predicted using a threat evaluation index system and was subdivided into four levels. Then, a technique evaluation index system containing four sets of criteria weights was constructed in stage 2 to obtain the optimum treatment schemes corresponding to the different threat levels. The applicability of the established evaluation system was tested by a practical cadmium-contaminated accident that occurred in 2012. The results show this system capable of facilitating scientific analysis in the evaluation and selection of emergency treatment technologies for drinking water source security.

Estimation on rubber tree disturbance caused by typhoon Damery (200518) with Landsat and MODIS data in Hainan Island of China

NASA Astrophysics Data System (ADS)

Tan, Chenyan; Fang, Weihua; Li, Jian

2016-04-01

In 2005, Typhoon Damery (200518) caused severe damage to the rubber trees in Hainan Island with its destructive winds and rainfall. Selection of proper vegetation indices using multi-source remote sensing data is critical to the assessment of forest disturbance and damage loss for this event. In this study, we will compare the performance of seven vegetation indices derived from MODIS and Landsat TM imageries prior to and after typhoon Damery, in order to select an optimal index for identifying rubber tree disturbance. The indices to be compared are normalized difference vegetation index (NDVI), Normalized Difference Water Index (NDWI), Normalized Difference Infrared Index (NDII), Enhanced vegetation index (EVI), Leaf area index (LAI), forest z-score (IFZ), and Disturbance Index (DI). The ground truth data of rubber tree damage collected through field investigation was used to verify and compare the results. Our preliminary result for the area with ground-truth data shows that DI has the most significant performance for disturbance detection for this typhoon event. This index DI is then applied to all the areas in Hainan Island hit by Darmey to evaluate the overall forest damage severity. At last, rubber tree damage severity is analyzed with other typhoon hazard factors such as wind, topography, soil and precipitation.

Evaluating Evapotranspiration of Pine Forest, Switchgrass, and Pine- Switchgrass Intercroppings using Remote Sensing and Ground-based Methods

NASA Astrophysics Data System (ADS)

Amatya, D. M.; Panda, S.; Chescheir, G. M.; Nettles, J. E.; Appelboom, T.; Skaggs, R. W.

2011-12-01

Vast areas of the land in the Southeastern United States are under pine forests managed primarily for timber and related byproducts. Evapotranspiration (ET) is the major loss in the water balance of this forest ecosystem. A long-term (1988-2008) study to evaluate hydrologic and nutrient balance during a life cycle of a pine stand was just completed. The study used both monitoring and modeling approaches to evaluate hydrologic and water quality effects of silvicultural and water management treatments on three 25 ha experimental watersheds in eastern North Carolina (NC). The research was extended in 2009 to include a dedicated energy crop, switchgrass (Panicum virgatum), by adding an adjacent 25 ha watershed. These multiple watersheds are being used to evaluate the hydrologic and water quality effects of switchgrass alone, young pine with natural understory, and young pine with switchgrass intercropping compared to the control (pine stand with a natural understory). The biofuels study has been further expanded to two other southern states, Alabama (AL) and Mississippi (MS). Each has five small watersheds (< 25 ha size) consisting of the above treatments and an additional woody biomass removal treatment. In this presentation we provide methods for estimating ET for these treatment watersheds in all three states (NC, AL, and MS) using remote sensing based spatial high resolution multispectral satellite imagery data with ground truthing, where possible, together with sensor technology. This technology is making ET parameter estimation a reality for various crops and vegetation surfaces. Slope-based vegetation indices like Normalized Difference Vegetation Index (NDVI) and Green Vegetation Index (GVI) and distance-based vegetation indices like Soil Adjusted Vegetation Index (SAVI) and Perpendicular Vegetation Index (PVI) will be developed using the R and NIR bands, vegetation density, and background soil reflectance as necessary. Landsat and high resolution aerial imageries of vegetation and soils will be used. IDRISI Taiga software will be used for the indices development. The forested vegetation health will be correlated to the leaf chlorophyll content for determining the vegetation health with a subsequent derivation of available plant water for radiation. Models will be developed to correlate the plant and soil available water to different vegetation indices. Correlation models will also be developed to obtain information on climatic parameters like surface air temperature, net radiation, albedo, soil moisture content, and stomatal water availability from Landsat imageries. On-site weather parameters used for the PET estimates will be combined with other vegetation parameters like leaf area index (LAI) obtained using LIDAR data and NAIP orthophotos of different seasons. That will also help detect the upper and understory vegetation. The LIDAR data will be processed to obtain the volume of vegetation to correctly estimate the total ET for each treatment.

Application of index number theory to the construction of a water quality index: aggregated nutrient loadings related to the areal extent of hypoxia in the northern Gulf of Mexico

USDA-ARS?s Scientific Manuscript database

The development of an index for description and monitoring of surface water quality has received significant attention in the water resources literature in recent years, primarily because of the increasing need for assessing water quality and the complex, multidimensional data collected from water q...

Habitat suitability index model of the sea cucumber Apostichopus japonicus (Selenka): A case study of Shandong Peninsula, China.

PubMed

Zhang, Zhipeng; Zhou, Jian; Song, Jingjing; Wang, Qixiang; Liu, Hongjun; Tang, Xuexi

2017-09-15

A habitat suitability index (HSI) model for the sea cucumber Apostichopus japonicus (Selenka) was established in the present study. Based on geographic information systems, the HSI model was used to identify potential sites around the Shandong Peninsula suitable for restoration of immature (<25g) and mature (>25g) A. japonicus. Six habitat factors were used as input variables for the HSI model: sediment classification, water temperature, salinity, water depth, pH and dissolved oxygen. The weighting of each habitat factor was defined through the Delphi method. Sediment classification was the most important condition affecting the HSI of A. japonicus in the different study areas, while water temperature was the most important condition in different seasons. The HSI of Western Laizhou Bay was relatively low, meaning the site was not suitable for aquaculture-based restoration of A. japonicus. In contrast, Xiaoheishan Island, Rongcheng Bay and Qingdao were preferable sites, suitable as habitats for restoration efforts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessing water scarcity in agricultural production system based on the generalized water resources and water footprint framework.

PubMed

Xinchun, Cao; Mengyang, Wu; Xiangping, Guo; Yalian, Zheng; Yan, Gong; Nan, Wu; Weiguang, Wang

2017-12-31

An indicator, agricultural water stress index (AWSI), was established based blue-green water resources and water footprint framework for regional water scarcity in agricultural production industry evaluation. AWSI is defined as the ratio of the total agricultural water footprint (AWF) to water resources availability (AWR) in a single year. Then, the temporal and spatial patterns of AWSI in China during 1999-2014 were analyzed based on the provincial AWR and AWF quantification. The results show that the annual AWR in China has been maintained at approximately 2540Gm 3 , of which blue water accounted for >70%. The national annual AWF was approximately 1040Gm 3 during the study period and comprised 65.6% green, 12.7% blue and 21.7% grey WFs The space difference in both the AWF for per unit arable land (AWFI) and its composition was significant. National AWSI was calculated as 0.413 and showed an increasing trend in the observed period. This index increased from 0.320 (mid-water stress level) in 2000 to 0.490 (high water stress level) in the present due to the expansion of the agricultural production scale. The Northern provinces, autonomous regions and municipalities (PAMs) have been facing high water stress, particularly the Huang-Huai-Hai Plain, which was at a very high water stress level (AWSI>0.800). Humid South China faces increasingly severe water scarcity, and most of the PAMs in the region have converted from low water stress level (AWSI=0.100-0.200) to mid water stress level (AWSI=0.200-0.400). The AWSI is more appropriate for reflecting the regional water scarcity than the existing water stress index (WSI) or the blue water scarcity (BWS) indicator, particularly for the arid agricultural production regions due to the revealed environmental impacts of agricultural production. China should guarantee the sustainable use of agricultural water resources by reducing its crop water footprint. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment of the water chemical quality improvement based on human health risk indexes: Application to a drinking water treatment plant incorporating membrane technologies.

PubMed

López-Roldán, Ramón; Rubalcaba, Alicia; Martin-Alonso, Jordi; González, Susana; Martí, Vicenç; Cortina, Jose Luis

2016-01-01

A methodology has been developed in order to evaluate the potential risk of drinking water for the health of the consumers. The methodology used for the assessment considered systemic and carcinogenic effects caused by oral ingestion of water based on the reference data developed by the World Health Organisation (WHO) and the Risk Assessment Information System (RAIS) for chemical contaminants. The exposure includes a hypothetical dose received by drinking this water according to the analysed contaminants. An assessment of the chemical quality improvement of produced water in the Drinking Water Treatment Plant (DWTP) after integration of membrane technologies was performed. Series of concentration values covering up to 261 chemical parameters over 5 years (2008-2012) of raw and treated water in the Sant Joan Despí DWTP, at the lower part of the Llobregat River basin (NE Spain), were used. After the application of the methodology, the resulting global indexes were located below the thresholds except for carcinogenic risk in the output of DWTP, where the index was slightly above the threshold during 2008 and 2009 before the upgrade of the treatment works including membrane technologies was executed. The annual evolution of global indexes showed a reduction in the global values for all situations: HQ systemic index based on RAIS dropped from 0.64 to 0.42 for surface water and from 0.61 to 0.31 for drinking water; the R carcinogenic index based on RAIS was negligible for input water and varied between 4.2×10(-05) and 7.4×10(-06) for drinking water; the W systemic index based on the WHO data varied between 0.41 and 0.16 for surface water and between 0.61 and 0.31 for drinking water. A specific analysis for the indexes associated with trihalomethanes (THMs) showed the same pattern. Copyright © 2015 Elsevier B.V. All rights reserved.

Developing a Water Quality Index (WQI) for an Irrigation Dam.

PubMed

De La Mora-Orozco, Celia; Flores-Lopez, Hugo; Rubio-Arias, Hector; Chavez-Duran, Alvaro; Ochoa-Rivero, Jesus

2017-04-29

Pollution levels have been increasing in water ecosystems worldwide. A water quality index (WQI) is an available tool to approximate the quality of water and facilitate the work of decision-makers by grouping and analyzing numerous parameters with a single numerical classification system. The objective of this study was to develop a WQI for a dam used for irrigation of about 5000 ha of agricultural land. The dam, La Vega, is located in Teuchitlan, Jalisco, Mexico. Seven sites were selected for water sampling and samples were collected in March, June, July, September, and December 2014 in an initial effort to develop a WQI for the dam. The WQI methodology, which was recommended by the Mexican National Water Commission (CNA), was used. The parameters employed to calculate the WQI were pH, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), total hardness (TH), alkalinity (Alk), total phosphorous (TP), Cl - , NO₃, SO₄, Ca, Mg, K, B, As, Cu, and Zn. No significant differences in WQI values were found among the seven sampling sites along the dam. However, seasonal differences in WQI were noted. In March and June, water quality was categorized as poor. By July and September, water quality was classified as medium to good. Quality then decreased, and by December water quality was classified as medium to poor. In conclusion, water treatment must be applied before waters from La Vega dam reservoir can be used for irrigation or other purposes. It is recommended that the water quality at La Vega dam is continually monitored for several years in order to confirm the findings of this short-term study.

Urban-rural differences in environmental quality and associations with adverse birth outcomes

EPA Science Inventory

Exposures affecting human health differ across environmental media and level of urbanicity. To address this, we constructed an Environmental Quality Index (EQI) with data representing five domains (air, water, land, built, sociodemographic) for each United States (U.S.) county. F...

A UAS-based remote sensing platform for crop water stress detection

NASA Astrophysics Data System (ADS)

Zhang, H.; Wang, D.; Ayars, J. E.

2014-12-01

The remote detection of water stress in a biofuel crop field was investigated using canopy temperature measurements. An experimental trial was set up in the central valley of Maui, Hawaii, comprising different sugarcane varieties and irrigation regimes. An unmanned aerial system (UAS) was equipped with a FLIR A615 thermal camera to acquire canopy temperature imagery. Images were mosaicked and processed to show spatial temperature difference of entire field. A weather station was installed in a full irrigation plot to collect meteorological parameters. The sensitivity of canopy to air temperature difference and crop water stress index were investigated on detecting cop water stress levels. The results showed that low irrigation level treatment plots resulted in higher canopy temperatures compared to the high irrigation level treatment plots. Canopy temperatures also showed differences in water stress in different sugarcane varieties. The study demonstrated the feasibility of UAS-based thermal method to quantify plant water status of sugar canes used for biofuel crops.

Combined Theoretical and Experimental Study of Refractive Indices of Water-Acetonitrile-Salt Systems.

PubMed

An, Ni; Zhuang, Bilin; Li, Minglun; Lu, Yuyuan; Wang, Zhen-Gang

2015-08-20

We propose a simple theoretical formula for describing the refractive indices in binary liquid mixtures containing salt ions. Our theory is based on the Clausius-Mossotti equation; it gives the refractive index of the mixture in terms of the refractive indices of the pure liquids and the polarizability of the ionic species, by properly accounting for the volume change upon mixing. The theoretical predictions are tested by extensive experimental measurements of the refractive indices for water-acetonitrile-salt systems for several liquid compositions, different salt species, and a range of salt concentrations. Excellent agreement is obtained in all cases, especially at low salt concentrations, with no fitting parameters. A simplified expression of the refractive index for low salt concentration is also given, which can be the theoretical basis for determination of salt concentration using refractive index measurements.

Daytime Changes of Skin Biophysical Characteristics: A Study of Hydration, Transepidermal Water Loss, pH, Sebum, Elasticity, Erythema, and Color Index on Middle Eastern Skin.

PubMed

Firooz, Alireza; Zartab, Hamed; Sadr, Bardia; Bagherpour, Leili Naraghi; Masoudi, Aidin; Fanian, Ferial; Dowlati, Yahya; Ehsani, Amir Hooshang; Samadi, Aniseh

2016-01-01

The exposure of skin to ultraviolet radiation and temperature differs significantly during the day. It is reasonable that biophysical parameters of human skin have periodic daily fluctuation. The objective of this study was to study the fluctuations of various biophysical characteristics of Middle Eastern skin in standardized experimental conditions. Seven biophysical parameters of skin including stratum corneum hydration, transepidermal water loss, pH, sebum, elasticity, skin color, and erythema index were measured at three time points (8 a.m., 12 p.m. and 4 p.m.) on the forearm of 12 healthy participants (mean age of 28.4 years) without any ongoing skin disease using the CK MPA 580 device in standard temperature and humidity conditions. A significant difference was observed between means of skin color index at 8 a.m. (175.42 ± 13.92) and 4 p.m. (164.44 ± 13.72, P = 0.025), between the pH at 8 a.m. (5.72 ± 0.48) and 4 p.m. (5.33 ± 0.55, P = 0.001) and pH at 12 p.m. (5.60 ± 0.48) and 4 p.m. (5.33 ± 0.55, P = 0.001). Other comparisons between the means of these parameters at different time points resulted in nonsignificant P values. There are daytime changes in skin color index and pH. Skin color index might be higher and cutaneous pH more basic in the early morning compared to later of the day.

Habitat Suitability Index Models: Red king crab

USGS Publications Warehouse

Jewett, Stephen C.; Onuf, Christopher P.

1988-01-01

A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for evaluating habitat of different life stages of red king crab (Paralithodes camtschatica). A model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat) in Alaskan coastal waters, especially in the Gulf of Alaska and the southeastern Bering Sea. HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

Water resources thesaurus: A vocabulary for indexing and retrieving the literature of water resources research and development

USGS Publications Warehouse

,

1980-01-01

This Water Resources Thesaurus encompasses such broad research areas as the hydrologic cycle, supply of and demand for water, conservation and best use of available supplies of water, methods of increasing supplies, and the economic, legal, social, engineering, recreational, biological, geographical, ecological, and qualitative aspects of water resources. This volume represents a major revision of the previous edition of the Thesaurus, published in 1971. The principal source of terms for this edition has been the indexing used in Selected Water Resources Abstracts (SWRA). Since its inception in 1968, SWRA has indexed tens of thousands of publications. Its indexing terminology has been developed by expert abstracters and researchers, and represents the range of disciplines related to research, development, and management of water resources.

A novel water poverty index model for evaluation of Chinese regional water security

NASA Astrophysics Data System (ADS)

Gong, L.; Jin, C. L.; Li, Y. X.; Zhou, Z. L.

2017-08-01

This study proposed an improved Water Poverty Index (WPI) model employed in evaluating Chinese regional water security. Firstly, the Chinese WPI index system was constructed, in which the indicators were obtained according to China River reality. A new mathematical model was then established for WPI values calculation on the basis of Center for Ecology and Hydrology (CEH) model. Furthermore, this new model was applied in Shiyanghe River (located in western China). It turned out that the Chinese index system could clearly reflect the indicators threatening security of river water and the Chinese WPI model is feasible. This work has also developed a Water Security Degree (WSD) standard which is able to be regarded as a scientific basis for further water resources utilization and water security warning mechanism formulation.

Definitions of components of the master water data index maintained by the National Water Data Exchange

USGS Publications Warehouse

Perry, R.A.; Williams, O.O.

1982-01-01

The Master Water Data Index is a computerized data base developed and maintained by the National Water Data Exchange (NAWDEX). The Index contains information about water-data collection sites. This information includes: the identification of new sites for which water data are available, the locations of these sites, the type of site, the data-collection organization, the types of data available, the major water-data parameters for which data are available, the frequency at which these parameters are measured, the period of time for which data are available, and the medial in which the data are stored. This document, commonly referred to as the MWDI data dictionary, contains a definition and description of each component of the Master Water Data Index data base. (USGS)

Trophic state and toxic cyanobacteria density in optimization modeling of multi-reservoir water resource systems.

PubMed

Sulis, Andrea; Buscarinu, Paola; Soru, Oriana; Sechi, Giovanni M

2014-04-22

The definition of a synthetic index for classifying the quality of water bodies is a key aspect in integrated planning and management of water resource systems. In previous works [1,2], a water system optimization modeling approach that requires a single quality index for stored water in reservoirs has been applied to a complex multi-reservoir system. Considering the same modeling field, this paper presents an improved quality index estimated both on the basis of the overall trophic state of the water body and on the basis of the density values of the most potentially toxic Cyanobacteria. The implementation of the index into the optimization model makes it possible to reproduce the conditions limiting water use due to excessive nutrient enrichment in the water body and to the health hazard linked to toxic blooms. The analysis of an extended limnological database (1996-2012) in four reservoirs of the Flumendosa-Campidano system (Sardinia, Italy) provides useful insights into the strengths and limitations of the proposed synthetic index.

Concentration and temperature dependence of the refractive index of ethanol-water mixtures: influence of intermolecular interactions.

PubMed

Riobóo, R J; Philipp, M; Ramos, M A; Krüger, J K

2009-09-01

The temperature and concentration dependence of the refractive index, nD(x, T), in ethanol-water mixtures agrees with previous data in the ethanol-rich concentration range. The refractive index versus concentration x determined at 20 degrees C shows the expected maximum at about 41 mol% water (22 mass% water). The temperature derivative of the refractive index, dnD/dT, shows anomalies at lower water concentrations at about 10 mol% water but no anomaly at 41 mol% water. Both anomalies are related to intermolecular interactions, the one in nD seems to be due to molecular segregation and cluster formation while the origin of the second one in dnD/dT is still not clear.

Light Refraction by Water as a Rationale for the Poggendorff Illusion.

PubMed

Bozhevolnyi, Sergey I

2016-08-24

The Poggendorff illusion in its classical form of parallel lines interrupting a transversal is viewed from the perspective of being related to the everyday experience of observing the light refraction in water. It is argued that if one considers a transversal to be a light ray in air and the parallel lines to form an occluding strip of a medium with the refractive index being between that of air and water, then one should be able to account, both qualitatively and quantitatively, for most of the features associated with the Poggendorff illusion. Statistical treatment of the visual experiments conducted with seven participants, each analyzing 50 configurations having different intercepting angles and strip widths, resulted in the effective refractive index of the occluding strip N = 1.13 ± 0.15, which is sufficiently close to the average (between that of water and air) refractive index of ∼1.17. It is further argued that the same mechanism can also be employed to account for many variants of the Poggendorff illusion, including the corner-Poggendorff pattern, as well as for the Hering illusion. © The Author(s) 2016.

Glophymed: an index to establish the ecological status for the Water Framework Directive based on phytoplankton in coastal waters.

PubMed

Romero, I; Pachés, M; Martínez-Guijarro, R; Ferrer, J

2013-10-15

Phytoplankton and its attributes (biomass, abundance, composition, and frequency and intensity of phytoplankton blooms) are essential to establish the ecological status in the Water Frame Directive. The aim of this study is to develop an index "Glophymed" based on all phytoplankton attributes for coastal water bodies according to the directive requirements. It is also developed an anthropogenic pressure index that takes into account population density, tourism, urbanization, industry, agriculture, fisheries and maritime transport for Comunitat Valenciana (Spain). Both indexes (Glophymed and human pressure index) based on a multisampling dataset collected monthly during several years, show a significant statistical correlation (r2 0.75 α<0.01) for typology IIA and (r2 0.93 α<0.01) for typology III-W. The relation between these indexes provides suitable information about the integrated management plans and protection measures of water resources since the Glophymed index is very sensitive to human pressures. Copyright © 2013 Elsevier Ltd. All rights reserved.

A new comprehensive index for drought monitoring with TM data

NASA Astrophysics Data System (ADS)

Wang, Yuanyuan

2017-10-01

Drought is one of the most important and frequent natural hazards to agriculture production in North China Plain. To improve agriculture water management, accurate drought monitoring information is needed. This study proposed a method for comprehensive drought monitoring by combining a meteorological index and three satellite drought indices of TM data together. SPI (Standard Precipitation Index), the meteorological drought index, is used to measure precipitation deficiency. Three satellite drought indices (Temperature Vegetation Drought Index, Land Surface Water Index, Modified Perpendicular Drought Index) are used to evaluate agricultural drought risk by exploring data from various channels (VIS, NIR, SWIR, TIR). Considering disparities in data ranges of different drought indices, normalization is implemented before combination. First, SPI is normalized to 0 — 100 given that its normal range is -4 - +4. Then, the three satellite drought indices are normalized to 0 - 100 according to the maximum and minimum values in the image, and aggregated using weighted average method (the result is denoted as ADI, Aggregated drought index). Finally, weighed geometric mean of SPI and ADI are calculated (the result is denoted as DIcombined). A case study in North China plain using three TM images acquired during April-May 2007 show that the method proposed in this study is effective. In spatial domain, DIcombined demonstrates dramatically more details than SPI; in temporal domain, DIcombined shows more reasonable drought development trajectory than satellite indices that are derived from independent TM images.

Adsorption of pharmaceuticals in water through lignocellulosic fibers synergism.

PubMed

Moro, Tatiana Rojo; Henrique, Francini Reis; Malucelli, Lucca Centa; de Oliveira, Cíntia Mara Ribas; da Silva Carvalho Filho, Marco Aurélio; de Vasconcelos, Eliane Carvalho

2017-03-01

The contamination of water from disposal of drugs is an emerging problem due to their consequences on trophic webs. This study evaluated the ability of sugarcane and coconut fiber to reduce water toxicity contaminated by pharmaceuticals. The toxicity of solutions containing pharmaceuticals was studied by bioassay using Allium cepa, before and after filtration of contaminated water. The coconut and sugarcane fiber have not been satisfactory in reducing toxicity when tested separately. Despite no induction of chromosomal aberrations, our study found a reduction of the mitotic index. The mixture of fibers showed better results providing total reduction of toxicity, in addition to maintenance in the mitotic index and induction of chromosome aberrations. The interaction between fibers and drugs was confirmed by Thermogravimetry and Differential Thermal Analyses (TG/DTA) which presented differences in profile between the fibers before and after adsorption. The mixture of coconut and sugarcane proved viable for reduction of toxicity in contaminated water by a mixture of pharmaceuticals. Copyright © 2016 Elsevier Ltd. All rights reserved.

A spectral water index based on visual bands

NASA Astrophysics Data System (ADS)

Basaeed, Essa; Bhaskar, Harish; Al-Mualla, Mohammed

2013-10-01

Land-water segmentation is an important preprocessing step in a number of remote sensing applications such as target detection, environmental monitoring, and map updating. A Normalized Optical Water Index (NOWI) is proposed to accurately discriminate between land and water regions in multi-spectral satellite imagery data from DubaiSat-1. NOWI exploits the spectral characteristics of water content (using visible bands) and uses a non-linear normalization procedure that renders strong emphasize on small changes in lower brightness values whilst guaranteeing that the segmentation process remains image-independent. The NOWI representation is validated through systematic experiments, evaluated using robust metrics, and compared against various supervised classification algorithms. Analysis has indicated that NOWI has the advantages that it: a) is a pixel-based method that requires no global knowledge of the scene under investigation, b) can be easily implemented in parallel processing, c) is image-independent and requires no training, d) works in different environmental conditions, e) provides high accuracy and efficiency, and f) works directly on the input image without any form of pre-processing.

Temporal trend and source apportionment of water pollution in different functional zones of Qiantang River, China.

PubMed

Su, Shiliang; Li, Dan; Zhang, Qi; Xiao, Rui; Huang, Fang; Wu, Jiaping

2011-02-01

The increasingly serious river water pollution in developing countries poses great threat to environmental health and human welfare. The assignment of river function to specific uses, known as zoning, is a useful tool to reveal variations of water environmental adaptability to human impact. Therefore, characterizing the temporal trend and identifying responsible pollution sources in different functional zones could greatly improve our knowledge about human impacts on the river water environment. The aim of this study is to obtain a deeper understanding of temporal trends and sources of water pollution in different functional zones with a case study of the Qiantang River, China. Measurement data were obtained and pretreated for 13 variables from 41 monitoring sites in four categories of functional zones during the period 1996-2004. An exploratory approach, which combines smoothing and non-parametric statistical tests, was applied to characterize trends of four significant parameters (permanganate index, ammonia nitrogen, total cadmium and fluoride) accounting for differences among different functional zones identified by discriminant analysis. Aided by GIS, yearly pollution index (PI) for each monitoring site was further mapped to compare the within-group variations in temporal dynamics for different functional zones. Rotated principal component analysis and receptor model (absolute principle component score-multiple linear regression, APCS-MLR) revealed that potential pollution sources and their corresponding contributions varied among the four functional zones. Variations of APCS values for each site of one functional zone as well as their annual average values highlighted the uncertainties associated with cross space-time effects in source apportionment. All these results reinforce the notion that the concept of zoning should be taken seriously in water pollution control. Being applicable to other rivers, the framework of management-oriented source apportionment is thus believed to have potentials to offer new insights into water management and advance the source apportionment framework as an operational basis for national and local governments. © 2010 Elsevier Ltd. All rights reserved.

Development of regression equations to revise estimates of historical streamflows for the St. Croix River at Stillwater, Minnesota (water years 1910-2011), and Prescott, Wisconsin (water years 1910-2007)

USGS Publications Warehouse

Ziegeweid, Jeffrey R.; Magdalene, Suzanne

2015-01-01

The new regression equations were used to calculate revised estimates of historical streamflows for Stillwater and Prescott starting in 1910 and ending when index-velocity streamgages were installed. Monthly, annual, 30-year, and period of record statistics were examined between previous and revised estimates of historical streamflows. The abilities of the new regression equations to estimate historical streamflows were evaluated by using percent differences to compare new estimates of historical daily streamflows to discrete streamflow measurements made at Stillwater and Prescott before the installation of index-velocity streamgages. Although less variability was observed between estimated and measured streamflows at Stillwater compared to Prescott, the percent difference data indicated that the new estimates closely approximated measured streamflows at both locations.

Impact on enzyme activity as a new quality index of wastewater.

PubMed

Balestri, Francesco; Moschini, Roberta; Cappiello, Mario; Del-Corso, Antonella; Mura, Umberto

2013-03-15

The aim of this study was to define a new indicator for the quality of wastewaters that are released into the environment. A quality index is proposed for wastewater samples in terms of the inertness of wastewater samples toward enzyme activity. This involves taking advantage of the sensitivity of enzymes to pollutants that may be present in the waste samples. The effect of wastewater samples on the rate of a number of different enzyme-catalyzed reactions was measured, and the results for all the selected enzymes were analyzed in an integrated fashion (multi-enzymatic sensor). This approach enabled us to define an overall quality index, the "Impact on Enzyme Function" (IEF-index), which is composed of three indicators: i) the Synoptic parameter, related to the average effect of the waste sample on each component of the enzymatic sensor; ii) the Peak parameter, related to the maximum effect observed among all the effects exerted by the sample on the sensor components; and, iii) the Interference parameter, related to the number of sensor components that are affected less than a fixed threshold value. A number of water based samples including public potable tap water, fluids from urban sewage systems, wastewater disposal from leather, paper and dye industries were analyzed and the IEF-index was then determined. Although the IEF-index cannot discriminate between different types of wastewater samples, it could be a useful parameter in monitoring the improvement of the quality of a specific sample. However, by analyzing an adequate number of waste samples of the same type, even from different local contexts, the profile of the impact of each component of the multi-enzymatic sensor could be typical for specific types of waste. The IEF-index is proposed as a supplementary qualification score for wastewaters, in addition to the certification of the waste's conformity to legal requirements. Copyright © 2013 Elsevier Ltd. All rights reserved.

Correlation of ADC value with pathologic indexes in colorectal tumor homografts in Balb/c mouse.

PubMed

Li, Xiaojun; Jiang, Hongnan; Niu, Jinliang; Zheng, Ying

2014-08-01

Noninvasive diffusion-weighted magnetic resonance imaging (DWI) is a well-studied MR imaging technique for quantifying water diffusion especially in tumor area. The correlation between apparent diffusion coefficient (ADC) value and apoptosis or proliferation is not clear by now. This study aimed to investigate whether DWI-ADC value could be used as an imaging marker related with pathologic indexes of tumors. A total of 30 Balb/c mice with HT29 colorectal carcinoma were subjected to DWI and histologic analysis. The percentage of ADC changes and the apoptotic and proliferating indexes were calculated at predefined time points. Kolmogorov-Smirnov distances were considered to determine whether the percentage of ADC changes, and the apoptotic and proliferating indexes were normally distributed. An independent-samples t-test was used to analyze the difference between apoptotic and proliferating indexes in the two groups. THERE WAS A STATISTICALLY SIGNIFICANT DIFFERENCE IN PROLIFERATING INDEX BETWEEN THE RADIOTHERAPY AND CONTROL GROUPS (MEAN PROLIFERATING INDEX: 49.27% vs. 83.09%), and there was a statistically significant difference in apoptotic index between the two groups (mean apoptotic index: 37.7% vs. 2.71%). A significant positive correlation was found between the percentage of ADC changes of the viable tissue and apoptotic index. Pearson's correlation coefficient was 0.655 (P=0.015). A significant negative correlation was found between the percentage of ADC changes of the viable tissue and ki-67 proliferation index. Pearson's correlation coefficient was 0.734 (P<0.001). Our results suggest that ADC value may be used in measurement of cell apoptotic and proliferating indexes in colorectal carcinoma.

[Spatial Variability Characteristics of Water Quality and Its Driving Forces in Honghu Lake During High Water-level Period].

PubMed

Li, Kun; Wang, Ling; Li, Zhao-hua; Wang, Xiang-rong; Chen, Hong-bing; Wu, Zhong; Zhu, Peng

2015-04-01

Based on the high-density analysis of 139 monitoring points and samples in water of honghu lake with different degrees of eutrophication during the high water-level period, we could get the figures of spatial variability characteristics of pollution factors, the biomass of aquatic plants and water quality in Honghu Lake using the GIS interpolation methods. The result showed that the concentrations of TN, TP, NH4(+) -N, permanganate index gradually increased from south to north during this period, the trend of water pollution degree in Honghu Lake was the region of inflowing rivers > enclosure culture area > open water area > the lake protection area > region of the Yangtze river into the lake; and the contribution rate of water quality parameters was in the order of TN > TP > permanganate index > NH4(+), -N > DO; under the influence of industrial sewage, agricultural sewage, domestic sewage, bait, aquatic plants and water exchange, 59% of TN, 35.2% of TP, 13.7% of permanganate index, 4.3% of NH4(+)-N exceeded the water quality targets, respectively, accordingly, 66.2% of the water quality also exceeded the water quality target. Nonetheless, DO reached the water quality target due to the influences of monsoon climate and other environment factors. The spatial variation analysis could directly reflect the mutual interaction among human activity, land-use types and environment factors which had an enormous impact on Honghu Lake water environment. In order to ensure that the lake water environment is beneficial for human productions and livings, it is necessary for us to control the discharge of industrial sewage, agricultural sewage and domestic sewage, as well as the expanding area of aquaculture, all the above measures would be significant for gradually resuming the self-purification capacity of water body and finally achieving the ecological sustainable development of Honghu Lake water environment.

Simplifying the Water Poverty Index

ERIC Educational Resources Information Center

Cho, Danny I.; Ogwang, Tomson; Opio, Christopher

2010-01-01

In this paper, principal components methodology is used to derive simplified and cost effective indexes of water poverty. Using a well known data set for 147 countries from which an earlier five-component water poverty index comprising of "Resources," "Access," "Capacity," "Use" and "Environment" was constructed, we find that a simplified…

Development of Water Quality Index for the United States: A Sensitivity Analysis

EPA Science Inventory

Background: Water quality is quantified using several measures, available from various data sources, which can be combined to create a single index of overall water quality. It is necessary to identify appropriate variables to include in an index which could be used for health re...

Testing the extended biotic index in Slovakia: consistency, advantages, and limitations versus the saprobic assessment method of water quality.

PubMed

Pennelli, Bruno; Nagel, Karl-Otto; Crivellaro, Giuseppe; Fabiani, Claudio; Vancova, Alexandra; Mancini, Laura

2006-04-01

The European Union Water Framework Directive requires the achievement of environmental objectives for the ecological quality of water bodies. A comparable implementation of the Directive throughout member countries of the European Union is necessary to verify equal protection of surface waters. The Directive specifies that member states determine ecological quality by means of biological indices. To improve comparability of water quality assessment, this research carried out an intercalibration trial between the Slovak Saprobic Index and the Italian protocol of the Extended Biotic Index, as part of a cooperative program between Italy and the Slovak Republic. When assessing streams with no or low pollution, statistics showed similar results for both methods. In contrast, the comparison of indices was not accurate in the case of severely affected waters. Reliable conversion formulas are feasible to transform the Italian Extended Biotic Index into the Slovak Saprobic Index, and not vice versa.

Assessment of water use in the Spanish irrigation district "Río Adaja"

NASA Astrophysics Data System (ADS)

Naroua, Illiassou; Rodriguez-Sinobas, Leonor; Sánchez Calvo, Raúl

2013-04-01

Intensive agricultural practices combined with the increasing pressure of urbanization and the changing lifestyles, have strengthened the problems of competing users over limited water resources in a fragile and already stressed environment. Sustainable irrigated agriculture is prescribed as a policy approach that maximizes economic benefits while maintaining environmental quality. Within this framework a proper management of irrigation systems saving water is required. On the other hand, crops with high tolerance to water stress and deficit irrigation are recommended. However, crop yield, among other factors, is very sensitive to water Thus, studies addressing the relations among crop water requirements, irrigation depth and crop yield are necessary. This type of study has been carried out in the Spanish irrigation District "Río Adaja" in the year 2010-2011 with the crops: wheat, barley, sugarbeet, corn, onion, potato, sunflower, clover and carrot. A soil hydrology balance model was applied taking into account climatic data for the nearby weather station and soil characteristics. Effective precipitation was calculated by the index curve number. Crop water requirements were calculated by the FAO Penman-Monteith with the application of the dual crop coefficient. Likewise, productivity was measured by the following indexes: annual relative irrigation supply (ARIS), relative water supply (RWS), relative rainfall supply (RS) and water productivity (WP). Results show that water applied with the irrigation of clover, sugarbeet, corn and onion was less than their water requirements There was a 35 % difference between the amount of water simulated with the model and the gross amount applied during the irrigation period by the irrigation district. WP values differed among crops depending, mainly, on the crop`s market price and the amount of irrigation water. The highest values corresponded to potato and onion crops.

Water Quality of a Reservoir and Its Major Tributary Located in East-Central Mexico

PubMed Central

Castilla-Hernández, Patricia; Torres-Alvarado, María del Rocío; Herrera-San Luis, José Antonio; Cruz-López, Norma

2014-01-01

A reservoir with ecological and economic importance and its major tributary, localized in east-central Mexico, were studied. The aim of this work was to know the physicochemical water characteristics of both water bodies and to contrast these by their different uses, and also estimate overall water quality using a Water Quality Index (WQI). Water samples from the reservoir and the tributary were obtained in different climatic seasons. In the tributary, anoxic and hypoxic conditions and high levels of organic matter, orthophosphate, and ammonium showed that this is strongly impacted by wastewater discharges and that the water is not suitable for different uses; independently of the season, the WQI showed “poor” quality (34.4–47.2). In contrast, in the reservoir a better water quality was determined; the WQI in the sampling months ranged from 72.1–76.6 (“good” quality), and spatially, this was from 66.5–79.5 (“fair” and “good” quality). PMID:24919132

Benthic invertebrates of fixed sites in the western Lake Michigan drainages, Wisconsin and Michigan, 1993-95

USGS Publications Warehouse

Lenz, Bernard N.; Rheaume, S.J.

2000-01-01

This report describes the variability in family-level benthic-invertebrate population data and the reliability of the data as a water-quality indicator for 11 fixed surface-water sites in the Western Lake Michigan Drainages study area of the National Water-Quality Assessment Program. Benthic-invertebrate-community measures were computed for the following: number of individuals, Hilsenhoff’s Family-Level Biotic Index, number and percent EPT (Ephemeroptera, Plecoptera, and Tricoptera), Margalef’s Diversity Index, and mean tolerance value. Relations between these measures and environmental setting, habitat, and of chemical water quality are examined. Benthic-invertebrate communities varied greatly among fixed sites and within individual streams among multiple-reach and multiple-year sampling. The variations between multiple reaches and years were sometimes larger than those found between different fixed sites. Factors affecting benthic invertebrates included both habitat and chemical quality. Generally, fixed-site streams with the highest diversity, greatest number of benthic invertebrates, and those at which community measures indicated the best water quality also had the best habitat and chemical quality. Variations among reaches are most likely related to differences in habitat. Variations among years are most likely related to climatic changes, which create variations in flow and/or chemical quality. The variability in the data analyzed in this study shows how benthic invertebrates are affected by differences in both habitat and water quality, making them useful indicators of stream health; however, a single benthic-invertebrate sample alone cannot be relied upon to accurately describe water quality of the streams in this study. Benthic-invertebrate data contributed valuable information on the biological health of the 11 fixed sites when used as one of several data sources for assessing water quality.

Development of a bacteria-based index of biotic integrity (Ba-IBI) for assessing ecological health of the Three Gorges Reservoir in different operation periods.

PubMed

Li, Yi; Yang, Nan; Qian, Bao; Yang, Zhengjian; Liu, Defu; Niu, Lihua; Zhang, Wenlong

2018-05-30

It is urgently needed to quantitatively assess ecological health of the Three Gorges Reservoir (TGR) when considering its special environmental conditions and temporal variations caused by reservoir operation. This study developed a bacteria-based index of biotic integrity (Ba-IBI) based on sediment samples collected along the TGR in low water level period, impoundment period and sluicing period, respectively. Reference conditions were defined using 8 ecological variables describing the hydromorphology and anthropogenic disturbances around the sites. Five core metrics, including % Acidobacteria, % Gemmatimonadetes, % Geobacter, Methanotroph and Phototroph, were selected after the screening processes. The developed index could clearly discriminate reference and impaired conditions and exhibited significant relationship with environmental parameters according to the redundancy (p < 0.01) and multivariable linear regression analysis (R 2  = 0.76). By implementing Ba-IBI in the TGR, the ecological health of the sampling sites was defined as "Excellent" (25%), "Good" (50%) and "Fair" (25%) separately. The spatial variation of biotic integrity was closely associated with environmental and ecological changes, especially the increase of nutrient concentrations. This study revealed a significant tendency that the ecological health in the low water level and sluicing periods was better than that in the impoundment period, which could be attributed to the hydrodynamic changes due to water level fluctuation. This study provides a comprehensive understanding of ecological health of the TGR in different operation periods and the index offers a guideline for the reservoir regulation in the similar areas. Copyright © 2018. Published by Elsevier B.V.

Development of a Coastal Drought Index Using Salinity Data

NASA Astrophysics Data System (ADS)

Conrads, P. A.; Darby, L. S.

2014-12-01

The freshwater-saltwater interface in surface-water bodies along the coast is an important factor in the ecological and socio-economic dynamics of coastal communities. It influences community composition in freshwater and saltwater ecosystems, determines fisheries spawning habitat, and controls freshwater availability for municipal and industrial water intakes. These dynamics may be affected by coastal drought through changes in Vibrio bacteria impacts on shellfish harvesting and occurrence of wound infection, fish kills, harmful algal blooms, hypoxia, and beach closures. There are many definitions of drought, with most describing a decline in precipitation having negative impacts on water supply and agriculture. Four general types of drought are recognized: hydrological, agricultural, meteorological, and socio-economic. Indices have been developed for these drought types incorporating data such as rainfall, streamflow, soil moisture, groundwater levels, and snow pack. These indices were developed for upland areas and may not be appropriate for characterizing drought in coastal areas. Because of the uniqueness of drought impacts on coastal ecosystems, a need exists to develop a coastal drought index. The availability of real-time and historical salinity datasets provides an opportunity to develop a salinity-based coastal drought index. The challenge of characterizing salinity dynamics in response to drought is excluding responses attributable to occasional saltwater intrusion events. Our approach to develop a coastal drought index modified the Standardized Precipitation Index and applied it to sites in South Carolina and Georgia, USA. Coastal drought indices characterizing 1-, 3-, 6-, 9-, and12-month drought conditions were developed. Evaluation of the coastal drought index indicates that it can be used for different estuary types, for comparison between estuaries, and as an index for wet conditions (high freshwater inflow) in addition to drought conditions.

Monitoring 2015 drought in West Java using Normalized Difference Water Index (NDWI)

NASA Astrophysics Data System (ADS)

Febrina Amalo, Luisa; Ma’rufah, Ummu; Ayu Permatasari, Prita

2018-05-01

Drought is a slow developing phenomenon that accumulates over period and affecting various sectors. It is one of natural hazards that occurs each year, particularly in Indonesia over Australian Monsoon period. During drought event, vegetation’s cover can be affected by water stress. Normalized Difference Water Index (NDWI) is a method for water resource assessment and known to be strongly related to the plant water content. NDWI is produced from MODIS bands Near-infrared (NIR) and Short Wave Infrared (SWIR). This research aims to monitor drought using NDWI in West Java during El Niño 2015 and its impact on rainfall variability. The result showed rainfall was decreased significantly starting from May-June, then increased in November. According to NDWI, it also showed that mostly West Java Region affected by drought during May-November. Very strong drought occurred on September-November. On December, areal extent of drought was decreasing significantly because rainfall had increased during November. Generally, areal extent of drought in West Java was dominated by strong and moderate drought. It implied that El Niño 2015, give great impact on increasing drought and decreasing rainfall in West Java. NDWI can be detected drought occurrence as it have good correlation with rainfall spatially.

The evaluation of basin water resources utilization efficiency based on Chaos projection mode

NASA Astrophysics Data System (ADS)

Guan, X.; Liang, S.; Meng, Y.; Wang, H.

2017-12-01

To promote the coordinated development of a healthy economy, society, and environment, and the sustainable development of water resources comprehensive utilization efficiency (WRCUE), this study investigated appropriate indicators using the trapezoidal fuzzy number method, and constructed an evaluation index system for WRCUE. A WRCUE evaluation model is applied to the areas in the Yellow River Basin in China using a genetic projection pursuit method. The comprehensive evaluation index system of water use efficiency includes 6 indicators: Water consumption per unit industrial value added, water consumption per unit GDP, eliminate the climate effect on agricultural water use efficiency, irrigation water consumption per unit area, domestic water use per capita and industrial water ratio. Then, multiple indexes in the index system are transformed to a comprehensive index by the combined model, which is used to represent the total water resources utilization efficiency. Results show that the WRCUE in Yellow River basin and the provinces have a great distance. WRCUE is well developed in Shanxi, Shandong, and Henan provinces, moderately developed in Shaanxi, Inner Mongolia, and Sichuan provinces, and poorly developed in the Ningxia Autonomous Region, Gansu Province, and Qinghai Province. According to the capacities of provinces, related measures are proposed.

Diversity, community composition, and dynamics of nonpigmented and late-pigmenting rapidly growing mycobacteria in an urban tap water production and distribution system.

PubMed

Dubrou, S; Konjek, J; Macheras, E; Welté, B; Guidicelli, L; Chignon, E; Joyeux, M; Gaillard, J L; Heym, B; Tully, T; Sapriel, G

2013-09-01

Nonpigmented and late-pigmenting rapidly growing mycobacteria (RGM) have been reported to commonly colonize water production and distribution systems. However, there is little information about the nature and distribution of RGM species within the different parts of such complex networks or about their clustering into specific RGM species communities. We conducted a large-scale survey between 2007 and 2009 in the Parisian urban tap water production and distribution system. We analyzed 1,418 water samples from 36 sites, covering all production units, water storage tanks, and distribution units; RGM isolates were identified by using rpoB gene sequencing. We detected 18 RGM species and putative new species, with most isolates being Mycobacterium chelonae and Mycobacterium llatzerense. Using hierarchical clustering and principal-component analysis, we found that RGM were organized into various communities correlating with water origin (groundwater or surface water) and location within the distribution network. Water treatment plants were more specifically associated with species of the Mycobacterium septicum group. On average, M. chelonae dominated network sites fed by surface water, and M. llatzerense dominated those fed by groundwater. Overall, the M. chelonae prevalence index increased along the distribution network and was associated with a correlative decrease in the prevalence index of M. llatzerense, suggesting competitive or niche exclusion between these two dominant species. Our data describe the great diversity and complexity of RGM species living in the interconnected environments that constitute the water production and distribution system of a large city and highlight the prevalence index of the potentially pathogenic species M. chelonae in the distribution network.

Diversity, Community Composition, and Dynamics of Nonpigmented and Late-Pigmenting Rapidly Growing Mycobacteria in an Urban Tap Water Production and Distribution System

PubMed Central

Dubrou, S.; Konjek, J.; Macheras, E.; Welté, B.; Guidicelli, L.; Chignon, E.; Joyeux, M.; Gaillard, J. L.; Heym, B.; Tully, T.

2013-01-01

Nonpigmented and late-pigmenting rapidly growing mycobacteria (RGM) have been reported to commonly colonize water production and distribution systems. However, there is little information about the nature and distribution of RGM species within the different parts of such complex networks or about their clustering into specific RGM species communities. We conducted a large-scale survey between 2007 and 2009 in the Parisian urban tap water production and distribution system. We analyzed 1,418 water samples from 36 sites, covering all production units, water storage tanks, and distribution units; RGM isolates were identified by using rpoB gene sequencing. We detected 18 RGM species and putative new species, with most isolates being Mycobacterium chelonae and Mycobacterium llatzerense. Using hierarchical clustering and principal-component analysis, we found that RGM were organized into various communities correlating with water origin (groundwater or surface water) and location within the distribution network. Water treatment plants were more specifically associated with species of the Mycobacterium septicum group. On average, M. chelonae dominated network sites fed by surface water, and M. llatzerense dominated those fed by groundwater. Overall, the M. chelonae prevalence index increased along the distribution network and was associated with a correlative decrease in the prevalence index of M. llatzerense, suggesting competitive or niche exclusion between these two dominant species. Our data describe the great diversity and complexity of RGM species living in the interconnected environments that constitute the water production and distribution system of a large city and highlight the prevalence index of the potentially pathogenic species M. chelonae in the distribution network. PMID:23835173

The Backscattering Enigma in Natural Waters

DTIC Science & Technology

2006-09-30

down because the effects of changing particle composition are not adequately understood. Our long term goal is to better understand the source of...natural waters. APPROACH A key focus over the last year has been determining the scattering properties of phytoplankton populations and...spaces, etc.), and forms the basis of the terrestrial biomass parameter NDVI (normalized difference vegetation index). However, plant cell structures

Effect of land cover and green space on land surface temperature of a fast growing economic region in Malaysia

NASA Astrophysics Data System (ADS)

Sheikhi, A.; Kanniah, K. D.; Ho, C. H.

2015-10-01

Green space must be increased in the development of new cities as green space can moderate temperature in the cities. In this study we estimated the land surface temperature (LST) and established relationships between LST and land cover and various vegetation and urban surface indices in the Iskandar Malaysia (IM) region. IM is one of the emerging economic gateways of Malaysia, and is envisaged to transform into a metropolis by 2025. This change may cause increased temperature in IM and therefore we conducted a study by using Landsat 5 image covering the study region (2,217 km2) to estimate LST, classify different land covers and calculate spectral indices. Results show that urban surface had highest LST (24.49 °C) and the lowest temperature was recorded in, forest, rubber and water bodies ( 20.69 to 21.02°C). Oil palm plantations showed intermediate mean LST values with 21.65 °C. We further investigated the relationship between vegetation and build up densities with temperature. We extracted 1000 collocated pure pixels of Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Normalized Difference Built-up Index (NDBI), Urban Index (UI) and LST in the study area. Results show a strong and significant negative correlation with (R2= -0.74 and -0.79) respectively between NDVI, NDWI and LST . Meanwhile a strong positive correlation (R2=0.8 and 0.86) exists between NDBI, UI and LST. These results show the importance of increasing green cover in urban environment to combat any adverse effects of climate change.

Capability of Hyperspectral data in Spatial Variability Distribution of Chlorophyll and Water Stress in Rice Agriculture System

NASA Astrophysics Data System (ADS)

Moharana, S.; Dutta, S.

2016-12-01

Abstract : The mapping and analysis of spatial variability within the field is a challenging task. However, field variability of a single vegetation cover does not give satisfactory results mainly due to low spectral resolution and non-availability of remote sensing data. From the NASA Earth Observing-1 (EO-1) satellite data, spatial distribution of biophysical parameters like chlorophyll and relative water content in a rice agriculture system is carried out in the present study. Hyperion L1R product composed of 242 spectral bands with 30m spatial resolution was acquired for Assam, India. This high dimensional data is allowed for pre-processing to get an atmospherically corrected imagery. Moreover, ground based hyperspectral measurements are collected from experimental rice fields from the study site using hand held ASD spectroradiometer (350-1050 nm). Published indices specifically designed for chlorophyll (OASVI, mSR, and MTCI indices) and water content (WI and WBI indices) are selected based on stastical performance of the in-situ hyperspectral data. Index models are established for the respective biophysical parameters and observed that the aforementioned indices followed different linear and nonlinear relationships which are completely different from the published indices. By employing the presently developed relationships, spatial variation of total chlorophyll and water stress are mapped for a rice agriculture system from Hyperion imagery. The findings showed that, the variation of chlorophyll and water content ranged from 1.77-10.61mg/g and 40-90% respectively for the studied rice agriculture system. The spatial distribution of these parameters resulted from presently developed index models are well captured from Hyperion imagery and they have good agreement with observed field based chlorophyll (1.14-7.26 mg/g) and water content (60-95%) of paddy crop. This study can be useful in providing essential information to assess the paddy field heterogeneity in an agriculture system. Keywords: Paddy crop, vegetation index, hyperspectral data, chlorophyll, water content

Development of Water Resources Drought Early Warning System

NASA Astrophysics Data System (ADS)

Chen, B. P. T.; Chen, C. H.

2017-12-01

Signs of impending drought are often vague and result from hydrologic uncertainty. Because of this, determining the appropriate time to enforce water supply restrictions is difficult. This study proposes a drought early warning index (DEWI) that can help water resource managers to anticipate droughts so that preparations can be made to mitigate the impact of water shortages. This study employs the expected-deficit-rate of normal water supply conditions as the drought early warning index. An annual-use-reservoir-based water supply system in southern Taiwan was selected as the case study. The water supply simulation was based on reservoir storage at the evaluation time and the reservoir inflow series to cope with the actual water supply process until the end of the hydrologic year. A variety of deficits could be realized during different hydrologic years of records and assumptions of initial reservoir storage. These deficits are illustrated using the Average Shortage Rate (ASR) and the value of the ASR, namely the DEWI. The ASR is divided into 5 levels according to 5 deficit-tolerance combinations of each kind of annual demand. A linear regression model and a Neuro-Fuzzy Computing Technique model were employed to estimate the DEWI using selected factors deduced from supply-demand traits and available information, including: rainfall, reservoir inflow and storage data. The chosen methods mentioned above are used to explain a significant index is useful for both model development and decision making. Tests in the Tsengwen-Wushantou reservoir system showed this DEWI to perform very well in adopting the proper mitigation policy at the end of the wet season.

Eutrophication in the Yunnan Plateau lakes: the influence of lake morphology, watershed land use, and socioeconomic factors.

PubMed

Liu, Wenzhi; Li, Siyue; Bu, Hongmei; Zhang, Quanfa; Liu, Guihua

2012-03-01

Lakes play an important role in socioeconomic development and ecological balance in China, but their water quality has deteriorated considerably in recent decades. In this study, we investigated the spatial-temporal variations of eutrophication parameters (secchi depth, total nitrogen, total phosphorus, chemical oxygen demand, chlorophyll-a, trophic level index, and trophic state index) and their relationships with lake morphology, watershed land use, and socioeconomic factors in the Yunnan Plateau lakes. Results indicated that about 77.8% of lakes were eutrophic according to trophic state index. The plateau lakes showed spatial variations in water quality and could be classified into high-nutrient and low-nutrient groups. However, because watersheds were dominated by vegetation, all eutrophication parameters except chlorophyll-a showed no significant differences between the wet and dry seasons. Lake depth, water residence time, volume, and percentage of built-up land were significantly related to several eutrophication parameters. Agricultural land use and social-economic factors had no significant correlation with all eutrophication parameters. Stepwise regression analyses demonstrated that lake depth and water residence time accounted for 73.8% to 87.6% of the spatial variation of single water quality variables, respectively. Redundancy analyses indicated that lake morphology, watershed land use, and socioeconomic factors together explained 74.3% of the spatial variation in overall water quality. The results imply that water quality degradation in the plateau lakes may be mainly due to the domestic and industrial wastewaters. This study will improve our understanding of the determinants of lake water quality and help to design efficient strategies for controlling eutrophication in the plateau region.

An investigation into dispersion upon switching between solvents within a microfluidic system using a chemically resistant integrated optical refractive index sensor.

PubMed

Parker, Richard M; Gates, James C; Wales, Dominic J; Smith, Peter G R; Grossel, Martin C

2013-02-07

A planar Bragg grating device has been developed that is capable of detecting changes in the refractive index of a wide range of fluids including solvents, acids and bases. The integration of this high precision refractive index sensor within a chemically resistant microfluidic flow system has enabled the investigation of diverse fluid interactions. By cycling between different solvents, both miscible and immiscible, within the microfluidic system it is shown that the previous solvent determines the nature of the refractive index profile across the transition in composition. This solvent dispersion effect is investigated with particular attention to the methanol-water transition, where transients in refractive index are observed that are an order of magnitude larger in amplitude than the difference between the bulk fluids. The potential complications of such phenomenon are discussed together with an example of a device that exploits this effect for the unambiguous composition measurement of a binary solvent system.

Quantitative diffusion and swelling kinetic measurements using large-angle interferometric refractometry.

PubMed

Saunders, John E; Chen, Hao; Brauer, Chris; Clayton, McGregor; Chen, Weijian; Barnes, Jack A; Loock, Hans-Peter

2015-12-07

The uptake and release of sorbates into films and coatings is typically accompanied by changes of the films' refractive index and thickness. We provide a comprehensive model to calculate the concentration of the sorbate from the average refractive index and the film thickness, and validate the model experimentally. The mass fraction of the analyte partitioned into a film is described quantitatively by the Lorentz-Lorenz equation and the Clausius-Mosotti equation. To validate the model, the uptake kinetics of water and other solvents into SU-8 films (d = 40-45 μm) were explored. Large-angle interferometric refractometry measurements can be used to characterize films that are between 15 μm to 150 μm thick and, Fourier analysis, is used to determine independently the thickness, the average refractive index and the refractive index at the film-substrate interface at one-second time intervals. From these values the mass fraction of water in SU-8 was calculated. The kinetics were best described by two independent uptake processes having different rates. Each process followed one-dimensional Fickian diffusion kinetics with diffusion coefficients for water into SU-8 photoresist film of 5.67 × 10(-9) cm(2) s(-1) and 61.2 × 10(-9) cm(2) s(-1).

Estimating the relative water content of leaves in a cotton canopy.

USDA-ARS?s Scientific Manuscript database

Remotely sensing plant canopy water status remains a long term goal of remote sensing research. Established approaches to estimating canopy water status — the Crop Water Stress Index, the Water Deficit Index, the Equivalent Water Thickness and the many other indices — involve measurements in the the...

Development of a coastal drought index using salinity data

USGS Publications Warehouse

Conrads, Paul; Darby, Lisa S.

2017-01-01

A critical aspect of the uniqueness of coastal drought is the effects on the salinity dynamics of creeks, rivers, and estuaries. The location of the freshwater–saltwater interface along the coast is an important factor in the ecological and socioeconomic dynamics of coastal communities. Salinity is a critical response variable that integrates hydrologic and coastal dynamics including sea level, tides, winds, precipitation, streamflow, and tropical storms. The position of the interface determines the composition of freshwater and saltwater aquatic communities as well as the freshwater availability for water intakes. Many definitions of drought have been proposed, with most describing a decline in precipitation having negative impacts on the water supply. Indices have been developed incorporating data such as rainfall, streamflow, soil moisture, and groundwater levels. These water-availability drought indices were developed for upland areas and may not be ideal for characterizing coastal drought. The availability of real-time and historical salinity datasets provides an opportunity for the development of a salinity-based coastal drought index. An approach similar to the standardized precipitation index (SPI) was modified and applied to salinity data obtained from sites in South Carolina and Georgia. Using the SPI approach, the index becomes a coastal salinity index (CSI) that characterizes coastal salinity conditions with respect to drought periods of higher-saline conditions and wet periods of higher-freshwater conditions. Evaluation of the CSI indicates that it provides additional coastal response information as compared to the SPI and the Palmer hydrologic drought index, and the CSI can be used for different estuary types and for comparison of conditions along coastlines.

Trophic State and Toxic Cyanobacteria Density in Optimization Modeling of Multi-Reservoir Water Resource Systems

PubMed Central

Sulis, Andrea; Buscarinu, Paola; Soru, Oriana; Sechi, Giovanni M.

2014-01-01

The definition of a synthetic index for classifying the quality of water bodies is a key aspect in integrated planning and management of water resource systems. In previous works [1,2], a water system optimization modeling approach that requires a single quality index for stored water in reservoirs has been applied to a complex multi-reservoir system. Considering the same modeling field, this paper presents an improved quality index estimated both on the basis of the overall trophic state of the water body and on the basis of the density values of the most potentially toxic Cyanobacteria. The implementation of the index into the optimization model makes it possible to reproduce the conditions limiting water use due to excessive nutrient enrichment in the water body and to the health hazard linked to toxic blooms. The analysis of an extended limnological database (1996–2012) in four reservoirs of the Flumendosa-Campidano system (Sardinia, Italy) provides useful insights into the strengths and limitations of the proposed synthetic index. PMID:24759172

Estimation of regional cutaneous cold sensitivity by analysis of the gasping response.

PubMed

Burke, W E; Mekjavić, I B

1991-11-01

Regional cutaneous sensitivity to cooling was assessed in males by separately immersing four discrete skin regions in cold water (15 degrees C) during head-out immersion. The response measured was gasping at the onset of immersion; the gasping response appears to be the result of a nonthermoregulatory neurogenic drive from cutaneous cold receptors. Subjects of similar body proportions wore a neoprene "dry" suit modified to allow exposure to the water of either the arms, upper torso, lower torso, or legs, while keeping the unexposed skin regions thermoneutral. Each subject was immersed to the sternal notch in all four conditions of partial exposure plus one condition of whole body exposure. The five cold water conditions were matched by control immersions in lukewarm (34 degrees C) water, and trials were randomized. The magnitude of the gasping response was determined by mouth occlusion pressure (P0.1). For each subject, P0.1 values for the 1st min of immersion were integrated, and control trial values, although minimal, were subtracted from their cold water counterpart to account for any gasping due to the experimental design. Results were averaged and showed that the highest P0.1 values were elicited from whole body exposure, followed in descending order by exposures of the upper torso, legs, lower torso, and arms. Correction of the P0.1 response for differences in exposed surface area (A) and cooling stimulus (delta T) between regions gave a cold sensitivity index [CSI, P0.1/(A.delta T)] for each region and showed that the index for the upper torso was significantly higher than that for the arms or legs; no significant difference was observed between the indexes for the upper and lower torso.(ABSTRACT TRUNCATED AT 250 WORDS)

Developing a Water Quality Index (WQI) for an Irrigation Dam

PubMed Central

De La Mora-Orozco, Celia; Flores-Lopez, Hugo; Rubio-Arias, Hector; Chavez-Duran, Alvaro; Ochoa-Rivero, Jesus

2017-01-01

Pollution levels have been increasing in water ecosystems worldwide. A water quality index (WQI) is an available tool to approximate the quality of water and facilitate the work of decision-makers by grouping and analyzing numerous parameters with a single numerical classification system. The objective of this study was to develop a WQI for a dam used for irrigation of about 5000 ha of agricultural land. The dam, La Vega, is located in Teuchitlan, Jalisco, Mexico. Seven sites were selected for water sampling and samples were collected in March, June, July, September, and December 2014 in an initial effort to develop a WQI for the dam. The WQI methodology, which was recommended by the Mexican National Water Commission (CNA), was used. The parameters employed to calculate the WQI were pH, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), total hardness (TH), alkalinity (Alk), total phosphorous (TP), Cl−, NO3, SO4, Ca, Mg, K, B, As, Cu, and Zn. No significant differences in WQI values were found among the seven sampling sites along the dam. However, seasonal differences in WQI were noted. In March and June, water quality was categorized as poor. By July and September, water quality was classified as medium to good. Quality then decreased, and by December water quality was classified as medium to poor. In conclusion, water treatment must be applied before waters from La Vega dam reservoir can be used for irrigation or other purposes. It is recommended that the water quality at La Vega dam is continually monitored for several years in order to confirm the findings of this short-term study. PMID:28468230

The Use of Index-Matched Beads in Optical Particle Counters

PubMed Central

Hu, Zhishang; Ripple, Dean C

2014-01-01

In this paper, we demonstrate the use of 2-pyridinemethanol (2P) aqueous solutions as a refractive index matching liquid. The high refractive index and low viscosity of 2P-water mixtures enables refractive index matching of beads that cannot be index matched with glycerol-water or sucrose-water solutions, such as silica beads that have the refractive index of bulk fused silica or of polymethylmethacrylate beads. Suspensions of beads in a nearly index-matching liquid are a useful tool to understand the response of particle counting instruments to particles of low optical contrast, such as aggregated protein particles. Data from flow imaging and light obscuration instruments are presented for bead diameters ranging from 6 µm to 69 µm, in a matrix liquid spanning the point of matched refractive index. PMID:26601049

Tunable two-dimensional liquid gradient refractive index (L-GRIN) lens for variable light focusing.

PubMed

Huang, Hua; Mao, Xiaole; Lin, Sz-Chin Steven; Kiraly, Brian; Huang, Yiping; Huang, Tony Jun

2010-09-21

We report a two-dimensional (2D) tunable liquid gradient refractive index (L-GRIN) lens for variable focusing of light in the out-of-plane direction. This lens focuses a light beam through a liquid medium with a 2D hyperbolic secant (HS) refractive index gradient. The refractive index gradient is established in a microfluidic chamber through the diffusion between two fluids with different refractive indices, i.e. CaCl(2) solution and deionized (DI) water. The 2D HS refractive index profile and subsequently the focal length of the L-GRIN lens can be tuned by changing the ratio of the flow rates of the CaCl(2) solution and DI water. The focusing effect is experimentally characterized through side-view and top-view image analysis, and the experimental data match well with the results from ray-tracing optical simulations. Advantages of the 2D L-GRIN lens include simple device fabrication procedure, low fluid consumption rate, convenient lens-tuning mechanism, and compatibility with existing microfluidic devices. We expect that with further optimizations, this 2D L-GRIN lens can be used in many optics-based lab-on-a-chip applications.

Challenges for implementing water quality monitoring and analysis on a small Costa Rican catchment

NASA Astrophysics Data System (ADS)

Golcher, Christian; Cernesson, Flavie; Tournoud, Marie-George; Bonin, Muriel; Suarez, Andrea

2016-04-01

The Costa Rican water regulatory framework (WRF) (2007), expresses the national concern about the degradation of surface water quality observed in the country since several years. Given the urgency of preserving and restoring the surface water bodies, and facing the need of defining a monitoring tool to classify surface water pollution, the Costa-Rican WRF relies on two water quality indexes: the so-called "Dutch Index" (D.I) and the Biological Monitoring Working Party adapted to Costa Rica (BMWP'CR), allowing an "easy" physicochemical and biological appraisal of the water quality and the ecological integrity of water bodies. Herein, we intend to evaluate whether the compound of water quality indexes imposed by Costa Rican legislation, is suitable to assess rivers local and global anthropogenic pressure and environmental conditions. We monitor water quality for 7 points of Liberia River (northern pacific region - Costa Rica) from March 2013 to July 2015. Anthropogenic pressures are characterized by catchment land use and riparian conditions. Environmental conditions are built from rainfall daily series. Our results show (i) the difficulties to monitor new sites following the recent implementation of the WRF; (ii) the statistical characteristics of each index; and (iii) a modelling tentative of relationships between water quality indexes and explanatory factors (land-use, riparian characteristics and climate conditions).

Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index.

PubMed

Li, Zheng; Zhou, Tao; Zhao, Xiang; Huang, Kaicheng; Gao, Shan; Wu, Hao; Luo, Hui

2015-07-08

Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI). We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI), from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months). When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation's responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April-October). The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages.

Decoupling of dissolved organic matter patterns between stream and riparian groundwater in a headwater forested catchment

NASA Astrophysics Data System (ADS)

Bernal, Susana; Lupon, Anna; Catalán, Núria; Castelar, Sara; Martí, Eugènia

2018-03-01

Streams are important sources of carbon to the atmosphere, though knowing whether they merely outgas terrestrially derived carbon dioxide or mineralize terrestrial inputs of dissolved organic matter (DOM) is still a big challenge in ecology. The objective of this study was to investigate the influence of riparian groundwater (GW) and in-stream processes on the temporal pattern of stream DOM concentrations and quality in a forested headwater stream, and whether this influence differed between the leaf litter fall (LLF) period and the remaining part of the year (non-LLF). The spectroscopic indexes (fluorescence index, biological index, humification index, and parallel factor analysis components) indicated that DOM had an eminently protein-like character and was most likely originated from microbial sources and recent biological activity in both stream water and riparian GW. However, paired samples of stream water and riparian GW showed that dissolved organic carbon (DOC) and nitrogen (DON) concentrations as well as the spectroscopic character of DOM differed between the two compartments throughout the year. A simple mass balance approach indicated that in-stream processes along the reach contributed to reducing DOC and DON fluxes by 50 and 30 %, respectively. Further, in-stream DOC and DON uptakes were unrelated to each other, suggesting that these two compounds underwent different biogeochemical pathways. During the LLF period, stream DOC and DOC : DON ratios were higher than during the non-LLF period, and spectroscopic indexes suggested a major influence of terrestrial vegetation on stream DOM. Our study highlights that stream DOM is not merely a reflection of riparian GW entering the stream and that headwater streams have the capacity to internally produce, transform, and consume DOM.

Daytime Changes of Skin Biophysical Characteristics: A Study of Hydration, Transepidermal Water Loss, pH, Sebum, Elasticity, Erythema, and Color Index on Middle Eastern Skin

PubMed Central

Firooz, Alireza; Zartab, Hamed; Sadr, Bardia; Bagherpour, Leili Naraghi; Masoudi, Aidin; Fanian, Ferial; Dowlati, Yahya; Ehsani, Amir Hooshang; Samadi, Aniseh

2016-01-01

Background: The exposure of skin to ultraviolet radiation and temperature differs significantly during the day. It is reasonable that biophysical parameters of human skin have periodic daily fluctuation. The objective of this study was to study the fluctuations of various biophysical characteristics of Middle Eastern skin in standardized experimental conditions. Materials and Methods: Seven biophysical parameters of skin including stratum corneum hydration, transepidermal water loss, pH, sebum, elasticity, skin color, and erythema index were measured at three time points (8 a.m., 12 p.m. and 4 p.m.) on the forearm of 12 healthy participants (mean age of 28.4 years) without any ongoing skin disease using the CK MPA 580 device in standard temperature and humidity conditions. Results: A significant difference was observed between means of skin color index at 8 a.m. (175.42 ± 13.92) and 4 p.m. (164.44 ± 13.72, P = 0.025), between the pH at 8 a.m. (5.72 ± 0.48) and 4 p.m. (5.33 ± 0.55, P = 0.001) and pH at 12 p.m. (5.60 ± 0.48) and 4 p.m. (5.33 ± 0.55, P = 0.001). Other comparisons between the means of these parameters at different time points resulted in nonsignificant P values. Conclusion: There are daytime changes in skin color index and pH. Skin color index might be higher and cutaneous pH more basic in the early morning compared to later of the day. PMID:27904203

Comparison of water extraction methods in Tibet based on GF-1 data

NASA Astrophysics Data System (ADS)

Jia, Lingjun; Shang, Kun; Liu, Jing; Sun, Zhongqing

2018-03-01

In this study, we compared four different water extraction methods with GF-1 data according to different water types in Tibet, including Support Vector Machine (SVM), Principal Component Analysis (PCA), Decision Tree Classifier based on False Normalized Difference Water Index (FNDWI-DTC), and PCA-SVM. The results show that all of the four methods can extract large area water body, but only SVM and PCA-SVM can obtain satisfying extraction results for small size water body. The methods were evaluated by both overall accuracy (OAA) and Kappa coefficient (KC). The OAA of PCA-SVM, SVM, FNDWI-DTC, PCA are 96.68%, 94.23%, 93.99%, 93.01%, and the KCs are 0.9308, 0.8995, 0.8962, 0.8842, respectively, in consistent with visual inspection. In summary, SVM is better for narrow rivers extraction and PCA-SVM is suitable for water extraction of various types. As for dark blue lakes, the methods using PCA can extract more quickly and accurately.

Collaborative, Rapid Mapping of Water Extents During Hurricane Harvey Using Optical and Radar Satellite Sensors

NASA Astrophysics Data System (ADS)

Muench, R.; Jones, M.; Herndon, K. E.; Bell, J. R.; Anderson, E. R.; Markert, K. N.; Molthan, A.; Adams, E. C.; Shultz, L.; Cherrington, E. A.; Flores, A.; Lucey, R.; Munroe, T.; Layne, G.; Pulla, S. T.; Weigel, A. M.; Tondapu, G.

2017-12-01

On August 25, 2017, Hurricane Harvey made landfall between Port Aransas and Port O'Connor, Texas, bringing with it unprecedented amounts of rainfall and flooding. In times of natural disasters of this nature, emergency responders require timely and accurate information about the hazard in order to assess and plan for disaster response. Due to the extreme flooding impacts associated with Hurricane Harvey, delineations of water extent were crucial to inform resource deployment. Through the USGS's Hazards Data Distribution System, government and commercial vendors were able to acquire and distribute various satellite imagery to analysts to create value-added products that can be used by these emergency responders. Rapid-response water extent maps were created through a collaborative multi-organization and multi-sensor approach. One team of researchers created Synthetic Aperture Radar (SAR) water extent maps using modified Copernicus Sentinel data (2017), processed by ESA. This group used backscatter images, pre-processed by the Alaska Satellite Facility's Hybrid Pluggable Processing Pipeline (HyP3), to identify and apply a threshold to identify water in the image. Quality control was conducted by manually examining the image and correcting for potential errors. Another group of researchers and graduate student volunteers derived water masks from high resolution DigitalGlobe and SPOT images. Through a system of standardized image processing, quality control measures, and communication channels the team provided timely and fairly accurate water extent maps to support a larger NASA Disasters Program response. The optical imagery was processed through a combination of various band thresholds by using Normalized Difference Water Index (NDWI), Modified Normalized Water Index (MNDWI), Normalized Difference Vegetation Index (NDVI), and cloud masking. Several aspects of the pre-processing and image access were run on internal servers to expedite the provision of images to analysts who could focus on manipulating thresholds and quality control checks for maximum accuracy within the time constraints. The combined results of the radar- and optical-derived value-added products through the coordination of multiple organizations provided timely information for emergency response and recovery efforts

Collaborative, Rapid Mapping of Water Extents During Hurricane Harvey Using Optical and Radar Satellite Sensors

NASA Technical Reports Server (NTRS)

Muench, Rebekke; Jones, Madeline; Herndon, Kelsey; Schultz, Lori; Bell, Jordan; Anderson, Eric; Markert, Kel; Molthan, Andrew; Adams, Emily; Cherrington, Emil;

[Effect of sampling effort on taxa richness of aquatic macroinvertebrates and the BMWP/Atitlán index].

PubMed

Reyes-Morales, Fátima; Springer, Monika

2014-04-01

Aquatic macroinvertebrates are the group of organisms most commonly used to determine ecosystem health in water quality studies and freshwater biomonitoring. Nevertheless, the methods and collecting time of biomonitoring have not yet been sufficiently adapted and tested in tropical aquatic environments. Twelve rivers in the Lago de Atitlán watershed in Guatemala were assessed with different collecting times, during the dry season. The method involved the collection of organic and inorganic material including benthic organisms, from different microhabitats, for a pre-established time period (5, 10, 15 min) with a D-frame net. Samples were preserved with 95% ethanol in the field, and sorted in the laboratory. As expected, the analysis showed that the abundance and taxonomic richness was higher with increasing sampling effort. The water quality categories obtained from the newly proposed BMWP/Atitlán index varied among sampling times. However, the Kruskal-Wallis test showed no significant differences between the categories obtained with the index and the number of taxa collected at 10 and 15 min. Therefore, we recommend a reduction of sample time, but maintaining the tree subsamples in order to include most variety of microhabitats and assure a representative sample of the aquatic macroinvertebrates.

Extreme Algal Bloom Detection with MERIS

NASA Astrophysics Data System (ADS)

Amin, R.; Gilerson, A.; Gould, R.; Arnone, R.; Ahmed, S.

2009-05-01

Harmful Algal Blooms (HAB's) are a major concern all over the world due to their negative impacts on the marine environment, human health, and the economy. Their detection from space still remains a challenge particularly in turbid coastal waters. In this study we propose a simple reflectance band difference approach for use with Medium Resolution Imaging Spectrometer (MERIS) data to detect intense plankton blooms. For convenience we label this approach as the Extreme Bloom Index (EBI) which is defined as EBI = Rrs (709) - Rrs (665). Our initial analysis shows that this band difference approach has some advantages over the band ratio approaches, particularly in reducing errors due to imperfect atmospheric corrections. We also do a comparison between the proposed EBI technique and the Maximum Chlorophyll Index (MCI) Gower technique. Our preliminary result shows that both the EBI and MCI indeces detect intense plankton blooms, however, MCI is more vulnerable in highly scattering waters, giving more positive false alarms than EBI.

Temporal water quality response in an urban river: a case study in peninsular Malaysia

NASA Astrophysics Data System (ADS)

VishnuRadhan, Renjith; Zainudin, Zaki; Sreekanth, G. B.; Dhiman, Ravinder; Salleh, Mohd. Noor; Vethamony, P.

2017-05-01

Ambient water quality is a prerequisite for the health and self-purification capacity of riverine ecosystems. To understand the general water quality situation, the time series data of selected water quality parameters were analyzed in an urban river in Peninsular Malaysia. In this regard, the stations were selected from the main stem of the river as well as from the side channel. The stations located at the main stem of the river are less polluted than that in the side channel. Water Quality Index scores indicated that the side channel station is the most polluted, breaching the Class IV water quality criteria threshold during the monitoring period, followed by stations at the river mouth and the main channel. The effect of immediate anthropogenic waste input is also evident at the side channel station. The Organic Pollution Index of side channel station is (14.99) 3 times higher than at stations at river mouth (4.11) and 6 times higher than at the main channel (2.57). The two-way ANOVA showed significant difference among different stations. Further, the factor analysis on water quality parameters yielded two significant factors. They discriminated the stations into two groups. The land-use land cover classification of the study area shows that the region near the sampling sites is dominated by urban settlements (33.23 %) and this can contribute significantly to the deterioration of ambient river water quality. The present study estimated the water quality condition and response in the river and the study can be an immediate yardstick for base lining river water quality, and a basis for future water quality modeling studies in the region.

Classifying Natural Waters with the Forel-Ule Colour Index System: Results, Applications, Correlations and Crowdsourcing.

PubMed

Garaba, Shungudzemwoyo P; Friedrichs, Anna; Voß, Daniela; Zielinski, Oliver

2015-12-18

Societal awareness of changes in the environment and climate has grown rapidly, and there is a need to engage citizens in gathering relevant scientific information to monitor environmental changes due to recognition that citizens are a potential source of critical information. The apparent colour of natural waters is one aspect of our aquatic environment that is easy to detect and an essential complementary optical water quality indicator. Here we present the results and explore the utility of the Forel-Ule colour index (FUI) scale as a proxy for different properties of natural waters. A FUI scale is used to distinguish the apparent colours of different natural surface water masses. Correlation analysis was completed in an effort to determine the constituents of natural waters related to FUI. Strong correlations with turbidity, Secchi-disk depth, and coloured dissolved organic material suggest the FUI is a good indicator of changes related to other constituents of water. The increase in the number of tools capable of determining the FUI colours, (i) ocean colour remote sensing products; (ii) a handheld scale; and (iii) a mobile device app, make it a versatile relative measure of water quality. It has the potential to provide higher spatial and temporal resolution of data for a modernized classification of optical water quality. This FUI colour system has been favoured by several scientists in the last century because it is affordable and easy to use and provides indicative information about the colour of water and the water constituents producing that colour. It is therefore within the scope of a growing interest in the application and usefulness of basic measurement methodologies with the potential to provide timely benchmark information about the environment to the public, scientists and policymakers.

Classifying Natural Waters with the Forel-Ule Colour Index System: Results, Applications, Correlations and Crowdsourcing

PubMed Central

Garaba, Shungudzemwoyo P.; Friedrichs, Anna; Voß, Daniela; Zielinski, Oliver

2015-01-01

Societal awareness of changes in the environment and climate has grown rapidly, and there is a need to engage citizens in gathering relevant scientific information to monitor environmental changes due to recognition that citizens are a potential source of critical information. The apparent colour of natural waters is one aspect of our aquatic environment that is easy to detect and an essential complementary optical water quality indicator. Here we present the results and explore the utility of the Forel-Ule colour index (FUI) scale as a proxy for different properties of natural waters. A FUI scale is used to distinguish the apparent colours of different natural surface water masses. Correlation analysis was completed in an effort to determine the constituents of natural waters related to FUI. Strong correlations with turbidity, Secchi-disk depth, and coloured dissolved organic material suggest the FUI is a good indicator of changes related to other constituents of water. The increase in the number of tools capable of determining the FUI colours, (i) ocean colour remote sensing products; (ii) a handheld scale; and (iii) a mobile device app, make it a versatile relative measure of water quality. It has the potential to provide higher spatial and temporal resolution of data for a modernized classification of optical water quality. This FUI colour system has been favoured by several scientists in the last century because it is affordable and easy to use and provides indicative information about the colour of water and the water constituents producing that colour. It is therefore within the scope of a growing interest in the application and usefulness of basic measurement methodologies with the potential to provide timely benchmark information about the environment to the public, scientists and policymakers. PMID:26694444

Optical diffusion property of chicken tissue

NASA Astrophysics Data System (ADS)

Schneider, Patricia S.; Flamholz, Alex; Wong, Peter K.; Lieberman, David H.; Cheung, Tak D.; Itoka, Harriet; Minott, Troy; Quizhpi, Janie; Rodriguez, Jacquelin

2004-11-01

Chicken tissue acts as a turbid medium in optical wavelength. Optical characterization data of fresh chicken dark and white meat were studied using the theory of light diffusion. The gaussian-like transmission profile was used to determine the transport mean free path and absorption. The refractive index, a fundamental parameter, was extracted via transmission correlation function analysis without using index-matching fluid. The variation in refractive index also produced various small shifts in the oscillatory feature of the intensity spatial correlation function at distance shorter than the transport mean free path. The optical system was calibrated with porous silicate slabs containing different water contents and also with a solid alumina slab. The result suggested that the selective scattering/absorption of myoglobin and mitochondria in the dark tissues is consistent with the transmission data. The refractive index was similar for dark and white tissues at the He-Ne wavelength and suggested that the index could serve as a marker for quality control. Application to chicken lunchmeat samples revealed that higher protein and lower carbohydrate would shift the correlation toward smaller distance. The pure fat refractive index was different from that of the meat tissue. Application of refractive index as a fat marker is also discussed

Composite measures of watershed health from a water quality perspective.

PubMed

Mallya, Ganeshchandra; Hantush, Mohamed; Govindaraju, Rao S

2018-05-15

Water quality data at gaging stations are typically compared with established federal, state, or local water quality standards to determine if violations (concentrations of specific constituents falling outside acceptable limits) have occurred. Based on the frequency and severity of water quality violations, risk metrics such as reliability, resilience, and vulnerability (R-R-V) are computed for assessing water quality-based watershed health. In this study, a modified methodology for computing R-R-V measures is presented, and a new composite watershed health index is proposed. Risk-based assessments for different water quality parameters are carried out using identified national sampling stations within the Upper Mississippi River Basin, the Maumee River Basin, and the Ohio River Basin. The distributional properties of risk measures with respect to water quality parameters are reported. Scaling behaviors of risk measures using stream order, specifically for the watershed health (WH) index, suggest that WH values increased with stream order for suspended sediment concentration, nitrogen, and orthophosphate in the Upper Mississippi River Basin. Spatial distribution of risk measures enable identification of locations exhibiting poor watershed health with respect to the chosen numerical standard, and the role of land use characteristics within the watershed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Contrasting Eutrophication Risks and Countermeasures in Different Water Bodies: Assessments to Support Targeted Watershed Management.

PubMed

Li, Tong; Chu, Chunli; Zhang, Yinan; Ju, Meiting; Wang, Yuqiu

2017-06-29

Eutrophication is a major problem in China. To combat this issue, the country needs to establish water quality targets, monitoring systems, and intelligent watershed management. This study explores a new watershed management method. Water quality is first assessed using a single factor index method. Then, changes in total nitrogen/total phosphorus (TN/TP) are analyzed to determine the limiting factor. Next, the study compares the eutrophication status of two water function districts, using a comprehensive nutritional state index method and geographic information system (GIS) visualization. Finally, nutrient sources are qualitatively analyzed. Two functional water areas in Tianjin, China were selected and analyzed: Qilihai National Wetland Nature Reserve and Yuqiao Reservoir. The reservoir is a drinking water source. Results indicate that total nitrogen (TN) and total phosphorus (TP) pollution are the main factors driving eutrophication in the Qilihai Wetland and Yuqiao Reservoir. Phosphorus was the limiting factor in the Yuqiao Reservoir; nitrogen was the limiting factor in the Qilihai Wetland. Pollution in Qilihai Wetland is more serious than in Yuqiao Reservoir. The study found that external sources are the main source of pollution. These two functional water areas are vital for Tianjin; as such, the study proposes targeted management measures.

Evaluation of different water-washing treatments effects on wheat straw combustion properties.

PubMed

Ma, Qiulin; Han, Lujia; Huang, Guangqun

2017-12-01

A series of experiments was conducted to explore the effects of various water-washing solid-liquid ratios (1:50 and 1:10) and the stirring on wheat straw (WS) combustion properties. Comparing different solid-liquid ratio groups, a 16% increment in the higher heating value was obtained for 1:50 groups and only 5% for 1:10 groups relative to the raw material. Moreover, energy was lost 4-26 times greater in 1:10 groups than 1:50 groups. While water-washing reduced the comprehensive combustibility index by 14.89%-32.09%, the index values of washed WS were all higher than 2, indicating good combustion performance. The combustion activation energy of four washed WS were 175, 172, 186, and 176kJ/mol, which were all higher than the 160kJ/mol of WS. The fouling/slagging propensity of washed WS reduced to a lower possibility compared to medium of untreated WS. Overall, the recommended condition for washing WS before combustion is 1:50 ratio without stirring. Copyright © 2017. Published by Elsevier Ltd.

Long-Term Remote Monitoring of Three Typical Lake Area Variations in the Northwest China Over the Past 40 Years

NASA Astrophysics Data System (ADS)

Liu, Y.; Lu, Y.; Li, Y.; Yue, H.

2018-04-01

water resources management and sustainable development strategy, but also provide reference for assessing the impact of climate change and human activities. This paper selects three inland lakes in Northwest China, using Landsat MSS/TM/ETM+/OLI data from 1970 to 2015, Normalized Difference Water Index (NDWI) and Modified Normalized Difference Water Index (MNDWI) were used to extract lake area and analysed the dynamic trends. Meteorological station rainfall, evaporation and other meteorological data of the lakes were used to analyse reasons for the area change. The results showed that area of Hongjiannao Lake in the past 40 a was reduced, the groundwater impoundment and underground coal mining are the main cause of area reduction; the area of Bosten Lake in recent 40 a showed a decreasing trend after the first increase, the area was mainly affected by the surface runoff and snowmelt; the area of Qinghai Lake in the past 40 a shows a trend of decreasing first and then increasing, the change of its area is mainly affected by regional precipitation and the inflow.

[Changes of bacterial community structure on reusing domestic sewage of Daoxianghujing Hotel to landscape water].

PubMed

Zhu, Jing-nan; Wang, Xiao-dan; Zhai, Zhen-hua; Ma, Wen-lin; Li, Rong-qi; Wang, Xue-lian; Li, Yan-hong

2010-05-01

A 16S rDNA library was used to evaluate the bacterial diversity and identify dominant groups of bacteria in different treatment pools in the domestic sewage system of the Beijing Daoxianghujing Hotel. The results revealed that there were many types of bacteria in the hotel domestic sewage, and the bacterial Shannon-Weaver diversity index was 3.12. In addition, epsilon Proteobacteria was found to be the dominant group with the ratio of 32%. In addition, both the CFB phylum, Fusobacteria, gamma Proteobacteria and Firmicutes were also reached to 9%-15%. After treated with the reclaimed water station, the bacterial Shannon-Weaver diversity index was reduced to 2. 41 and beta Proteobacteria became the dominant group and occupied 73% of the total clones. However, following artificial wetland training, the bacterial Shannon-Weaver diversity index in the sample increased to 3.38, Actinobacteria arrived to 33% and became the most dominant group; Cyanobacteria reached to 26%, and was the second dominant group. But, the control sample comprised 38% Cyanobacteria, and mainly involved in Cyanobium, Synechoccus and Microcystis, with ratios of 47.1%, 17.6% and 8.8%, respectively. Some bacteria of Microcystis aenruginosa were also detected, which probably resulted in the light bloom finally. Therefore, the bacterial diversity and community structures changed in response to treatment of the hotel domestic sewage; there was no cyanobacteria bloom explosion in the treated water. This study will aid in investigation the changes of microbial ecology in different types of water and providing the useful information for enhancing the cyanobacteria blooms control from ecological angle.

Effect of Water Invasion on Outburst Predictive Index of Low Rank Coals in Dalong Mine

PubMed Central

Jiang, Jingyu; Cheng, Yuanping; Mou, Junhui; Jin, Kan; Cui, Jie

2015-01-01

To improve the coal permeability and outburst prevention, coal seam water injection and a series of outburst prevention measures were tested in outburst coal mines. These methods have become important technologies used for coal and gas outburst prevention and control by increasing the external moisture of coal or decreasing the stress of coal seam and changing the coal pore structure and gas desorption speed. In addition, techniques have had a significant impact on the gas extraction and outburst prevention indicators of coal seams. Globally, low rank coals reservoirs account for nearly half of hidden coal reserves and the most obvious feature of low rank coal is the high natural moisture content. Moisture will restrain the gas desorption and will affect the gas extraction and accuracy of the outburst prediction of coals. To study the influence of injected water on methane desorption dynamic characteristics and the outburst predictive index of coal, coal samples were collected from the Dalong Mine. The methane adsorption/desorption test was conducted on coal samples under conditions of different injected water contents. Selective analysis assessed the variations of the gas desorption quantities and the outburst prediction index (coal cutting desorption index). Adsorption tests indicated that the Langmuir volume of the Dalong coal sample is ~40.26 m3/t, indicating a strong gas adsorption ability. With the increase of injected water content, the gas desorption amount of the coal samples decreased under the same pressure and temperature. Higher moisture content lowered the accumulation desorption quantity after 120 minutes. The gas desorption volumes and moisture content conformed to a logarithmic relationship. After moisture correction, we obtained the long-flame coal outburst prediction (cutting desorption) index critical value. This value can provide a theoretical basis for outburst prediction and prevention of low rank coal mines and similar occurrence conditions of coal seams. PMID:26161959

[The new method monitoring crop water content based on NIR-Red spectrum feature space].

PubMed

Cheng, Xiao-juan; Xu, Xin-gang; Chen, Tian-en; Yang, Gui-jun; Li, Zhen-hai

2014-06-01

Moisture content is an important index of crop water stress condition, timely and effective monitoring of crop water content is of great significance for evaluating crop water deficit balance and guiding agriculture irrigation. The present paper was trying to build a new crop water index for winter wheat vegetation water content based on NIR-Red spectral space. Firstly, canopy spectrums of winter wheat with narrow-band were resampled according to relative spectral response function of HJ-CCD and ZY-3. Then, a new index (PWI) was set up to estimate vegetation water content of winter wheat by improveing PDI (perpendicular drought index) and PVI (perpendicular vegetation index) based on NIR-Red spectral feature space. The results showed that the relationship between PWI and VWC (vegetation water content) was stable based on simulation of wide-band multispectral data HJ-CCD and ZY-3 with R2 being 0.684 and 0.683, respectively. And then VWC was estimated by using PWI with the R2 and RMSE being 0.764 and 0.764, 3.837% and 3.840%, respectively. The results indicated that PWI has certain feasibility to estimate crop water content. At the same time, it provides a new method for monitoring crop water content using remote sensing data HJ-CCD and ZY-3.

SEEING THE LIGHT: A WATER CLARITY INDEX FOR INTEGRATED WATER QUALITY ASSESSMENTS

EPA Science Inventory

Smith, Lisa M. and Linda C. Harwell. In press. Seeing the Light: A Water Clarity Index for Integrated Water Quality Assessments (Abstract). To be presented at EMAP Symposium 2004: Integrated Monitoring & Assessment for Effective Water Quality Management. 1 p. (ERL,GB R970).
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Effect of disopyramide on bacterial diversity in drinking water

NASA Astrophysics Data System (ADS)

Wu, Qing; Zhao, Xiaofei; Tian, Qi; Wang, Lei; Zhao, Xinhua

2018-02-01

Disopyramide was detected in drinking water by LC-MS/MS and the microbial diversity was investigated by PCR and high-throughput sequencing. The results showed that bacteria community structure in drinking water changed a lot when added different concentrations of disopyramide. The results of Shannon index showed that the total number and abundance of bacterial community species in drinking water samples decreased significantly after the addition of disopyramide. However, the number and abundance of community structure did not change with the concentration of disopyramide. Disopyramide inhibits the activity of bacterial community in drinking water and also can reduce the bacterial community diversity in drinking water.

Multivariate statistical evaluation of dissolved trace elements and a water quality assessment in the middle reaches of Huaihe River, Anhui, China.

PubMed

Wang, Jie; Liu, Guijian; Liu, Houqi; Lam, Paul K S

2017-04-01

A total of 211 water samples were collected from 53 key sampling points from 5-10th July 2013 at four different depths (0m, 2m, 4m, 8m) and at different sites in the Huaihe River, Anhui, China. These points monitored for 18 parameters (water temperature, pH, TN, TP, TOC, Cu, Pb, Zn, Ni, Co, Cr, Cd, Mn, B, Fe, Al, Mg, and Ba). The spatial variability, contamination sources and health risk of trace elements as well as the river water quality were investigated. Our results were compared with national (CSEPA) and international (WHO, USEPA) drinking water guidelines, revealing that Zn, Cd and Pb were the dominant pollutants in the water body. Application of different multivariate statistical approaches, including correlation matrix and factor/principal component analysis (FA/PCA), to assess the origins of the elements in the Huaihe River, identified three source types that accounted for 79.31% of the total variance. Anthropogenic activities were considered to contribute much of the Zn, Cd, Pb, Ni, Co, and Mn via industrial waste, coal combustion, and vehicle exhaust; Ba, B, Cr and Cu were controlled by mixed anthropogenic and natural sources, and Mg, Fe and Al had natural origins from weathered rocks and crustal materials. Cluster analysis (CA) was used to classify the 53 sample points into three groups of water pollution, high pollution, moderate pollution, and low pollution, reflecting influences from tributaries, power plants and vehicle exhaust, and agricultural activities, respectively. The results of the water quality index (WQI) indicate that water in the Huaihe River is heavily polluted by trace elements, so approximately 96% of the water in the Huaihe River is unsuitable for drinking. A health risk assessment using the hazard quotient and index (HQ/HI) recommended by the USEPA suggests that Co, Cd and Pb in the river could cause non-carcinogenic harm to human health. Copyright © 2017 Elsevier B.V. All rights reserved.

Physiological Assessment of Water Stress in Potato Using Spectral Information

PubMed Central

Romero, Angela P.; Alarcón, Andrés; Valbuena, Raúl I.; Galeano, Carlos H.

2017-01-01

Water stress in potato (Solanum tuberosum L.) causes considerable losses in yield, and therefore, potato is often considered to be a drought sensitive crop. Identification of water deficit tolerant potato genotypes is an adaptation strategy to mitigate the climatic changes that are occurring in the Cundiboyacense region in Colombia. Previous studies have evaluated potato plants under water stress conditions using physiological analyses. However, these methodologies require considerable amounts of time and plant material to perform these measurements. This study evaluated and compared the physiological and spectral traits between two genotypes, Diacol Capiro and Perla Negra under two drought levels (10 and 15 days without irrigation from flowering). Reflectance information was used to calculate indexes which were associated with the physiological behavior in plants. The results showed that spectral information was correlated (ρ < 0.0001) with physiological variables such as foliar area (FA), total water content (H2Ot), relative growth rate of potato tubers (RGTtub), leaf area ratio (LAR), and foliar area index (AFI). In general, there was a higher concentration of chlorophyll under drought treatments. In addition, Perla Negra under water deficit treatments did not show significant differences in its physiological variables. Therefore, it could be considered a drought tolerant genotype because its physiological performance was not affected under water stress conditions. However, yield was affected in both genotypes after being subject to 15 days of drought. The results suggested that reflectance indexes are a useful and affordable approach for potato phenotyping to select parent and segregant populations in breeding programs. PMID:28979277

18 CFR 3a.91 - Data index system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Data index system. 3a.91 Section 3a.91 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES NATIONAL SECURITY INFORMATION Data Index System § 3a.91 Data index system...

18 CFR 3a.91 - Data index system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Data index system. 3a.91 Section 3a.91 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES NATIONAL SECURITY INFORMATION Data Index System § 3a.91 Data index system...

18 CFR 3a.91 - Data index system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Data index system. 3a.91 Section 3a.91 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES NATIONAL SECURITY INFORMATION Data Index System § 3a.91 Data index system...

18 CFR 3a.91 - Data index system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Data index system. 3a.91 Section 3a.91 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES NATIONAL SECURITY INFORMATION Data Index System § 3a.91 Data index system...

Combining ground-based measurements and satellite-based spectral vegetation indices to track biomass accumulation in post-fire chaparral

NASA Astrophysics Data System (ADS)

Uyeda, K. A.; Stow, D. A.; Roberts, D. A.; Riggan, P. J.

2015-12-01

Multi-temporal satellite imagery can provide valuable information on patterns of vegetation growth over large spatial extents and long time periods, but corresponding ground-referenced biomass information is often difficult to acquire, especially at an annual scale. In this study, I test the relationship between annual biomass estimated using shrub growth rings and metrics of seasonal growth derived from Moderate Resolution Imaging Spectroradiometer (MODIS) spectral vegetation indices (SVIs) for a small area of southern California chaparral to evaluate the potential for mapping biomass at larger spatial extents. The site had most recently burned in 2002, and annual biomass accumulation measurements were available from years 5 - 11 post-fire. I tested metrics of seasonal growth using six SVIs (Normalized Difference Vegetation Index, Enhanced Vegetation Index, Soil Adjusted Vegetation Index, Normalized Difference Water Index, Normalized Difference Infrared Index 6, and Vegetation Atmospherically Resistant Index). While additional research would be required to determine which of these metrics and SVIs are most promising over larger spatial extents, several of the seasonal growth metrics/ SVI combinations have a very strong relationship with annual biomass, and all SVIs have a strong relationship with annual biomass for at least one of the seasonal growth metrics.

Application of Dynamic naïve Bayesian classifier to comprehensive drought assessment

NASA Astrophysics Data System (ADS)

Park, D. H.; Lee, J. Y.; Lee, J. H.; KIm, T. W.

2017-12-01

Drought monitoring has already been extensively studied due to the widespread impacts and complex causes of drought. The most important component of drought monitoring is to estimate the characteristics and extent of drought by quantitatively measuring the characteristics of drought. Drought assessment considering different aspects of the complicated drought condition and uncertainty of drought index is great significance in accurate drought monitoring. This study used the dynamic Naïve Bayesian Classifier (DNBC) which is an extension of the Hidden Markov Model (HMM), to model and classify drought by using various drought indices for integrated drought assessment. To provide a stable model for combined use of multiple drought indices, this study employed the DNBC to perform multi-index drought assessment by aggregating the effect of different type of drought and considering the inherent uncertainty. Drought classification was performed by the DNBC using several drought indices: Standardized Precipitation Index (SPI), Streamflow Drought Index (SDI), and Normalized Vegetation Supply Water Index (NVSWI)) that reflect meteorological, hydrological, and agricultural drought characteristics. Overall results showed that in comparison unidirectional (SPI, SDI, and NVSWI) or multivariate (Composite Drought Index, CDI) drought assessment, the proposed DNBC was able to synthetically classify of drought considering uncertainty. Model provided method for comprehensive drought assessment with combined use of different drought indices.

Technological Aspects of Waterworks Sludge Treatment

NASA Astrophysics Data System (ADS)

Belkanova, M. Yu; Nikolaenko, E. V.; Gevel, D. A.

2017-11-01

The water yielding capacity of the sludge in water-supply network treatment facilities is determined by the water quality in a water source and its treatment technology. The paper studies the sludge of water-supply network treatment facilities formed in the conditions of low turbidity and average water colour index in the water source. Such sludge has a low water yielding capacity and is subject to conditioning. The paper shows the influence of seasonal variations of turbidity, water colour index and temperature of the feed water on the specific sludge filtration resistance. It considers the specific features of sludge formation in different settling basins influencing its water yielding capacity. It is shown that the washwater return performed at one of the blocks of the facilities increases the feed water turbidity and leads to the formation of the sludge easily susceptible to conditioning. The paper studies the following methods of the reagent sludge treatment: polyacrylamide-based flocculant treatment, joint treatment with flocculant and vermiculite filler, lime treatment. The use of vermiculite allows to reduce the required flocculant dose. The author determines optimum doses of reagents allowing to direct the sludge for further mechanical dewatering after conditioning. It is shown that, when the sludge is processed with lime, the filtrate formed at dewatering can be reused as an alkalifying agent, which will allow one to cut the costs for the acquisition of reagents.

A 4-year assessment of a new water-fluoridation scheme in New South Wales, Australia.

PubMed

Blinkhorn, Anthony S; Byun, Roy; Mehta, Pathik; Kay, Meredith

2015-06-01

To monitor the changes in dental caries prevalence of 5- to 7-year-old children living in a fluoridated area, a newly fluoridated area and in an area without water fluoridation, in NSW, Australia. Dental caries prevalence was recorded for 5- to 7-year-old children, living in the three study locations, by six trained and calibrated examiners in 2008, 2010 and 2012. A questionnaire recorded demographic data, toothbrushing behaviour and sugary drink consumption. Caries experience was measured using the decayed, missing, and filled teeth (dmft) index for primary teeth, the percentage of children who were caries free and the significant caries index. Univariate analysis was undertaken to determine independent predictors of caries. The caries prevalence changed over time. In 2008, the mean dmft index was 1.40 for the fluoridated area, 2.02 for the area about to fluoridate and 2.09 for the unfluoridated control. By 2012, these mean dmft scores were 0.69, 0.72 and 1.21, respectively. In the two areas where children received fluoridated water, the significant caries index was 2.30 for the fluoridated area and 2.40 for the newly fluoridated area. The significant caries score for children in the unfluoridated location was 3.93. Multivariate analysis showed that over time the differences in dental caries prevalence between the established fluoride area and the newly fluoridated area diminished. However, children in the unfluoridated control area continued to demonstrate significant differences in the mean number of decayed teeth compared with children in the fluoridated comparator sites, and the proportions of children free from decay were significantly higher in the fluoridated areas than in the unfluoridated area. Fluoridation of public water supplies in Gosford and Wyong offers young children better dental health than those children who do not have access to this public health measure. © 2015 FDI World Dental Federation.

Indexing method for assessment of pollution potential of leachate from non-engineered landfill sites and its effect on ground water quality.

PubMed

Rana, Rishi; Ganguly, Rajiv; Gupta, Ashok Kumar

2017-12-26

Dumping of solid waste in a non-engineered landfill site often leads to contamination of ground water due to leachate percolation into ground water. The present paper assesses the pollution potential of leachate generated from three non-engineered landfill sites located in the Tricity region (one each in cities of Chandigarh, Mohali and Panchkula) of Northern India and its possible effects of contamination of groundwater. Analysis of physico-chemical properties of leachate from all the three landfill sites and the surrounding groundwater samples from five different downwind distances from each of the landfill sites were collected and tested to determine the leachate pollution index (LPI) and the water quality index (WQI). The Leachate Pollution Index values of 26.1, 27 and 27.8 respectively for landfill sites of Chandigarh (CHD), Mohali (MOH) and Panchkula (PKL) cities showed that the leachate generated are contaminated. The average pH values of the leachate samples over the sampling period (9.2 for CHD, 8.97 for MOH and 8.9 for PKL) show an alkaline nature indicating that all the three landfill sites could be classified as mature to old stage. The WQI calculated over the different downwind distances from the contamination sites showed that the quality of the groundwater improved with an increase in the downwind distance. Principal component analysis (PCA) carried out established major components mainly from natural and anthropogenic sources with cumulative variance of 88% for Chandigarh, 87.1% for Mohali and 87.8% for Panchkula. Hierarchical cluster analysis (HCA) identifies three distinct cluster types for the groundwater samples. These clusters corresponds to a relatively low pollution, moderate pollution and high pollution regions. It is suggested that all the three non-engineered landfill sites be converted to engineered landfill sites to prevent groundwater contamination and also new sites be considered for construction of these engineered landfill sites as the present dumpsites are nearing the end of their lifespan capacity.

An index of refraction algorithm for seawater over temperature, pressure, salinity, density, and wavelength

NASA Astrophysics Data System (ADS)

Millard, R. C.; Seaver, G.

1990-12-01

A 27-term index of refraction algorithm for pure and sea waters has been developed using four experimental data sets of differing accuracies. They cover the range 500-700 nm in wavelength, 0-30°C in temperature, 0-40 psu in salinity, and 0-11,000 db in pressure. The index of refraction algorithm has an accuracy that varies from 0.4 ppm for pure water at atmospheric pressure to 80 ppm at high pressures, but preserves the accuracy of each original data set. This algorithm is a significant improvement over existing descriptions as it is in analytical form with a better and more carefully defined accuracy. A salinometer algorithm with the same uncertainty has been created by numerically inverting the index algorithm using the Newton-Raphson method. The 27-term index algorithm was used to generate a pseudo-data set at the sodium D wavelength (589.26 nm) from which a 6-term densitometer algorithm was constructed. The densitometer algorithm also produces salinity as an intermediate step in the salinity inversion. The densitometer residuals have a standard deviation of 0.049 kg m -3 which is not accurate enough for most oceanographic applications. However, the densitometer algorithm was used to explore the sensitivity of density from this technique to temperature and pressure uncertainties. To achieve a deep ocean densitometer of 0.001 kg m -3 accuracy would require the index of refraction to have an accuracy of 0.3 ppm, the temperature an accuracy of 0.01°C and the pressure 1 db. Our assessment of the currently available index of refraction measurements finds that only the data for fresh water at atmospheric pressure produce an algorithm satisfactory for oceanographic use (density to 0.4 ppm). The data base for the algorithm at higher pressures and various salinities requires an order of magnitude or better improvement in index measurement accuracy before the resultant density accuracy will be comparable to the currently available oceanographic algorithm.

A Multi-Scale Sampling Strategy for Detecting Physiologically Significant Signals in AVIRIS Imagery

NASA Technical Reports Server (NTRS)

Gamon, John A.; Lee, Lai-Fun; Qiu, Hong-Lie; Davis, Stephen; Roberts, Dar A.; Ustin, Susan L.

1998-01-01

Models of photosynthetic production at ecosystem and global scales require multiple input parameters specifying physical and physiological surface features. While certain physical parameters (e.g., absorbed photosynthetically active radiation) can be derived from current satellite sensors, other physiologically relevant measures (e.g., vegetation type, water status, carboxylation capacity, or photosynthetic light-use efficiency), are not generally directly available from current satellite sensors at the appropriate geographic scale. Consequently, many model parameters must be assumed or derived from independent sources, often at an inappropriate scale. An abundance of ecophysiological studies at the leaf and canopy scales suggests strong physiological control of vegetation-atmosphere CO2 and water vapor fluxes, particularly in evergreen vegetation subjected to diurnal or seasonal stresses. For example hot, dry conditions can lead to stomatal closure, and associated "downregulation" of photosynthetic biochemical processes, a phenomenon often manifested as a "midday photosynthetic depression". A recent study with the revised simple biosphere (SiB2) model demonstrated that photosynthetic downregulation can significantly impact global climate. However, at the global scale, the exact significance of downregulation remains unclear, largely because appropriate physiological measures are generally unavailable at this scale. Clearly, there is a need to develop reliable ways of extracting physiologically relevant information from remote sensing. Narrow-band spectrometers offer many opportunities for deriving physiological parameters needed for ecosystem and global scale photosynthetic models. Experimental studies on the ground at the leaf- to stand-scale have indicated that several narrow-band features can be used to detect plant physiological status. One physiological signal is caused by xanthophyll cycle pigment activity, and is often expressed as the Photochemical Reflectance Index (PRI). Because the xanthophyll cycle pigments are photoregulatory pigments closely linked to photosynthetic function, this index can be used to derive relative photosynthetic rates. An additional signal with physiological significance is the 970 nm water absorption band, which provides a measure of liquid water content. This feature has been quantified both using a simple 2-band ratio (900/970 nm, here referred to as the "Water Band Index" or WBI;), and using the "continuum removal" method. Current atmospheric correction methods for AVIRIS imagery also obtain quantitative expressions of surface liquid water absorption based on the 970 nm water band and may be comparable to ground-based estimates of water content using this feature. However, physiological interpretations of both the PRI and the WBI are best understood at the leaf and canopy scales, where complications of atmospheric interference and complex stand and landscape features can be minimized, and where experimental manipulations can be readily applied. Currently it is not known whether these physiological indices can be used to derive meaningful physiological information from AVIRIS imagery. In addition to the problem of atmospheric interference, another challenge is that any simple physiological index can be confounded by multiple factors unrelated to physiology, and this problem can become more severe at progressively larger spatial scales. For example, previous work has suggested that both the PRI and the WBI, are strongly correlated with other optical measures of canopy structure (e.g., the Normalized Difference Vegetation Index or green vegetation fraction), indicating a confounding effect of structure on physiological signals at the larger, landscape scale. Furthermore, the normal operating mode of most imaging spectrometers does not allow simultaneous, ground truthing at a level of detail needed for physiological sampling. Additionally, manipulative experiments of physiology are difficult to apply at a geographic scale suitable for comparison with remote imagery, which often works at spatial scales that are several orders of magnitude larger than those typically used for physiological studies. These limitations require the consideration of alternative approaches to validating physiological information derived from AVIRIS data. In this report, we present a multi-scale sampling approach to detecting physiologically significant signals in narrow-band spectra. This approach explores the multi-dimensional data space provided by narrow-band spectrometry, and combines AVIRIS imagery at a large scale, with ground spectral sampling at an intermediate scale, and detailed ecophysiological measurements at a fine scale, to examine seasonally and spatially changing relationships between multiple structural and physiological variables. Examples of this approach are provided by simultaneous sampling of the Normalized Difference Vegetation Index (NDVI), an index of fractional PAR interception and green vegetation cover, the Water Band Index (WBI, an index of liquid water absorption, and the Photochemical Reflectance Index (PRI, an index of xanthophyll cycle pigment activity and photosynthetic light-use efficiency. By directly linking changing optical properties sampled on the ground with measurable physiological states, we hope to develop a basis for interpreting similar signals in AVIRIS imagery.

A new experimental correlation for non-Newtonian behavior of COOH-DWCNTs/antifreeze nanofluid

NASA Astrophysics Data System (ADS)

Izadi, Farhad; Ranjbarzadeh, Ramin; Kalbasi, Rasool; Afrand, Masoud

2018-04-01

In this paper, the rheological behavior of nano-antifreeze consisting of 50%vol. water, 50%vol. ethylene glycol and different quantities of functionalized double walled carbon nanotubes has been investigated experimentally. Initially, nano-antifreeze samples were prepared with solid volume fractions of 0.05, 0.1, 0.2, 0.4, 0.6, 0.8 and 1% using two-step method. Then, the dynamic viscosity of the nano-antifreeze samples was measured at different shear rates and temperatures. At this stage, the results showed that base fluid had the Newtonian behavior, while the behavior of all nano-antifreeze samples was non-Newtonian. Since the behavior of the samples was similar to power law model, it was attempted to find the constants of this model including consistency index and power law index. Therefore, using the measured viscosity and shear rates, consistency index and power law index were obtained by curve-fitting method. The obtained values showed that consistency index amplified with increasing volume fraction, while reduced with enhancing temperature. Besides, the obtained values for power law index were less than 1 for all samples which means shear thinning behavior. Lastly, new correlations were suggested to estimate the consistency index and power law index using curve-fitting.

Drinking water composition and incidence of urinary calculus: introducing a new index.

PubMed

Basiri, Abbas; Shakhssalim, Nasser; Khoshdel, Ali Reza; Pakmanesh, Hamid; Radfar, Mohammad Hadi

2011-01-01

INTRODUCTION. We searched for a pathophysiologically based feature of major water electrolytes, which may define water quality better than the water hardness, respecting urinary calculus formation. MATERIALS AND METHODS. Utilizing a multistage stratified sampling, 2310 patients were diagnosed in the imaging centers of the provincial capitals in Iran between 2007 and 2008. These were composed of 1755 patients who were settled residents of 24 provincial capitals. Data on the regional drinking water composition, obtained from an accredited registry, and their relationships with the region's incidence of urinary calculi were evaluated by metaregression models. The stone risk index (defined as the ratio of calcium to magnesium-bicarbonate product in drinking water) was used to assess the risk of calculus formation. RESULTS. No correlation was found between the urinary calculus incidence and the amount of calcium, bicarbonate, or the total hardness of the drinking water. In contrast, water magnesium had a marginally significant nonlinear inverse relationship with the incidence of the disease in the capitals (R(2) = 26%, P = .05 for a power model). The stone risk index was associated nonlinearly with the calculus incidence (R(2) = 28.4%, P = .04). CONCLUSIONS. Urinary calculus incidence was inversely related with drinking water magnesium content. We introduced a new index constructed on the foundation of a pathophysiologically based formula; the stone risk index had a strong positive association with calculus incidence. This index can have therapeutic and preventive applications, yet to be confirmed by clinical trials.

Water security evaluation in Yellow River basin

NASA Astrophysics Data System (ADS)

Jiang, Guiqin; He, Liyuan; Jing, Juan

2018-03-01

Water security is an important basis for making water security protection strategy, which concerns regional economic and social sustainable development. In this paper, watershed water security evaluation index system including 3 levels of 5 criterion layers (water resources security, water ecological security and water environment security, water disasters prevention and control security and social economic security) and 24 indicators were constructed. The entropy weight method was used to determine the weights of the indexes in the system. The water security index of 2000, 2005, 2010 and 2015 in Yellow River basin were calculated by linear weighting method based on the relative data. Results show that the water security conditions continue to improve in Yellow River basin but still in a basic security state. There is still a long way to enhance the water security in Yellow River basin, especially the water prevention and control security, the water ecological security and water environment security need to be promoted vigorously.

A global assessment of wildfire risks to human and environmental water security

NASA Astrophysics Data System (ADS)

Robinne, François-Nicolas; Parisien, Marc-André; Flannigan, Mike; Miller, Carol; Bladon, Kevin D.

2017-04-01

Extreme wildfire events extensively affect hydrosystem stability and generate an important threat to the reliability of the water supply for human and natural communities. While actively studied at the watershed scale, the development of a global vision of wildfire risk to water security has only been undertaken recently, pointing at potential water security concerns in an era of global changes. In order to address this concern, we propose a global-scale analysis of the wildfire risk to surface water supplies based on the Driving forces-Pressures-States-Impacts-Responses (DPSIR) framework. This framework relies on the cause-and-effect relationships existing between the five categories of the DPSIR chain. Based on the literature, we gathered an extensive set of spatial indicators relevant to fire-induced hydrological hazards and water consumption patterns by human and natural communities. Each indicator was assigned a DPSIR category. Then, we collapsed the information in each category using a principal component analysis in order to extract the most relevant pixel-based information provided by each spatial indicator. Finally, we compiled our five categories using an additive indexation process to produce a spatially-explicit index of the wildfire-water risk (WWR). For comparison purposes, we aggregated index scores by global hydrological regions, or hydrobelts, for analysis. Overall, our results show a distinct pattern of medium-to-high risk levels in areas where sizeable wildfire activity, water resources, and water consumption are concomitant, which mainly encompasses temperate and sub-tropical zones. A closer look at hydrobelts reveals differences in the factors driving the risk, with fire activity being the primary factor of risk in the circumboreal forest, and freshwater resource density being prevalent in tropical areas. We also identified major urban areas across the world whose source waters should be protected from extreme fire events, particularly when they are dependent on mountainous headwaters. This study offers new insights towards a better understanding of global water security issues that can inform and help guide international water governance.

Can a canopy temperature-based stress index enhance water use efficiency in irrigated wine grape under arid conditions?

USDA-ARS?s Scientific Manuscript database

Enhancement of irrigation water use efficiency and water productivity in arid wine grape production regions is hindered by a lack of automated, real-time methods for monitoring and interpreting vine water status. A normalized, water stress index calculated from real-time vine canopy temperature meas...

Phytoplankton community as bioindicator of fertility in belawan river

NASA Astrophysics Data System (ADS)

Sari Yeanny, Mayang

2018-03-01

Belawan River is an important river for the Medan residents and its surroundings. It serves as the main raw material for the local drinking water company, as well as domestic, industrial, hotel and tourism. Many human activities had led to the declining condition of water in the river throughout the year. One way to approach the concept of bioindicator is by knowing Abundance, Relative Abundance, Frequency of Attendance, equitability, dominance, and diversity of the phytoplankton itself. Results indicated that the phytoplankton community was from 3 different classes: Chlorophyceae, Bacillariophyceae, and Cyanophyceae. Phytoplankton individual abundance was around 2612 to 17755 ind / L. The diversity index was around 2.15 to 2.58, which is considered to have low to moderate diversity with high pollution level. Equitability Index was approaching 0, with relatively high domination from Sphaeroplea and Asterionella. The water quality that influences the diversity of phytoplankton as bioindicator was dissolved oxygen.

Synthesis and characterization of rice starch laurate as food-grade emulsifier for canola oil-in-water emulsions.

PubMed

García-Tejeda, Y V; Leal-Castañeda, E J; Espinosa-Solis, V; Barrera-Figueroa, V

2018-08-15

The effect of esterification on hydrolyzed rice starch was analyzed, for this aim rice starch was hydrolyzed and subsequently esterified with lauroyl chloride at three modification levels. Starch derivatives were characterized regarding their degree of substitution (DS), water solubility index, z-potential, gelatinization, and digestibility properties. DS of derivatives of rice starch laurate ranged from 0.042 to 1.86. It was determined that after esterification the water solubility index increased from 3.44 to 53.61%, the z-potential decreased from -3.18 to -11.27, and the content of slowly digestible starch (SDS) decreased from 26.22 to 5.13%. Different emulsions with starch concentrations ranging from 6 to 30 wt% were evaluated. The most stable emulsions were those having 20 and 30 wt% of rice starch laurate. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Wetness Index Using Terrain-Corrected Surface Temperature and Normalized Difference Vegetation Index Derived from Standard MODIS Products: An Evaluation of Its Use in a Humid Forest-Dominated Region of Eastern Canada

PubMed Central

Hassan, Quazi K.; Bourque, Charles P.-A.; Meng, Fan-Rui; Cox, Roger M.

2007-01-01

In this paper we develop a method to estimate land-surface water content in a mostly forest-dominated (humid) and topographically-varied region of eastern Canada. The approach is centered on a temperature-vegetation wetness index (TVWI) that uses standard 8-day MODIS-based image composites of land surface temperature (TS) and surface reflectance as primary input. In an attempt to improve estimates of TVWI in high elevation areas, terrain-induced variations in TS are removed by applying grid, digital elevation model-based calculations of vertical atmospheric pressure to calculations of surface potential temperature (θS). Here, θS corrects TS to the temperature value to what it would be at mean sea level (i.e., ∼101.3 kPa) in a neutral atmosphere. The vegetation component of the TVWI uses 8-day composites of surface reflectance in the calculation of normalized difference vegetation index (NDVI) values. TVWI and corresponding wet and dry edges are based on an interpretation of scatterplots generated by plotting θS as a function of NDVI. A comparison of spatially-averaged field measurements of volumetric soil water content (VSWC) and TVWI for the 2003-2005 period revealed that variation with time to both was similar in magnitudes. Growing season, point mean measurements of VSWC and TVWI were 31.0% and 28.8% for 2003, 28.6% and 29.4% for 2004, and 40.0% and 38.4% for 2005, respectively. An evaluation of the long-term spatial distribution of land-surface wetness generated with the new θS-NDVI function and a process-based model of soil water content showed a strong relationship (i.e., r2 = 95.7%). PMID:28903212

Land area change and fractional water maps in the Chenier Plain, Louisiana, following hurricane Rita

NASA Astrophysics Data System (ADS)

Palaseanu-Lovejoy, M.; Kranenburg, C.; Brock, J. C.

2009-12-01

The objective of this study is to develop a fractional water map at 30-m resolution scale using QuickBird and/or IKONOS high-resolution imagery as dependent variable to investigate the impact of hurricane Rita in the Chenier Plain, Louisiana. Eleven different indices were tested to obtain a high-resolution land / water classification on QuickBird (acquired on 05/23/2003) and IKONOS (acquired on 03/25/2006) images. The percent area covered by water in the high resolution images varied from 22 to 26% depending on the index used , with the simple ratio index (red band / NIR band) accounting for the lowest percent and the blue ratio index (blue band / sum(all bands)) for the highest percent. Using the ERDAS NLCD (National Land Cover Data) Mapping tool module, 100, 000 stratified random sample points with minimum 1000 points per stratum were selected from the high resolution dependent variable as training information for the independent variable layers. The rules for the regression tree were created using the data mining software Rulequest Cubist v. 2.05. This information was used to generate a fractional water map for the entire Landsat scene. The increase in water areas of about 10 - 15% between 2003 to 2006, as well as temporary changes in the water - land configurations are attributed to remnant flooding and removal of aquatic vegetation caused by hurricane Rita, and water level variations caused by tidal and / or meteorological variations between the acquisition dates of the satellite images. This analysis can assist in monitoring post-hurricane wetland recovery and assess trends in land loss due to extreme storm events, although estimation of permanent land loss cannot be made until wetland areas have the opportunity to recover from hurricane impacts.

WATER QUALITY AND ASSOCIATIONS WITH GASTROINTESTINAL CONDITIONS

EPA Science Inventory

Water quality is quantified using several measures, available from various data sources. These can be combined to create a single index of overall water quality which can be used for health research. We developed a water quality index for all United States counties and assessed a...

Land Use/Land Cover Changes and Its Response to Hydrological Characteristics in the Upper Reaches of Minjiang River

NASA Astrophysics Data System (ADS)

Ma, Kai; Huang, Xiaorong; Guo, Biying; Wang, Yanqiu; Gao, Linyun

2018-06-01

Land use changes alter the hydrological characteristics of the land surface, and have significant impacts on hydrological cycle and water balance, the analysis of complex effects on natural systems has become one of the main concerns. In this study, we generated the land use conversion matrixes using ArcGIS and selected several landscape indexes (contagion index, CONTAG, Shannon's diversity index, SHDI, etc.) to evaluate the impact of land use/cover changes on hydrological process in the upper reaches of Minjiang River. We also used a statistical regression model which was established based on hydrology and precipitation data during the period of 1959-2008 to simulate the impacts of different land use conditions on rainfall and runoff in different periods. Our results showed that the simulated annual mean flow from 1985 to 1995 and 1995 to 2008 are 9.19 and 1.04 m3 s-1 lower than the measured values, respectively, which implied that the ecological protection measures should be strengthened in the study area. Our study could provide a scientific basis for water resource management and proper land use planning of upper reaches of Minjiang River.

Hierarchical structure of the energy landscape of proteins revisited by time series analysis. II. Investigation of explicit solvent effects

NASA Astrophysics Data System (ADS)

Alakent, Burak; Camurdan, Mehmet C.; Doruker, Pemra

2005-10-01

Time series analysis tools are employed on the principal modes obtained from the Cα trajectories from two independent molecular-dynamics simulations of α-amylase inhibitor (tendamistat). Fluctuations inside an energy minimum (intraminimum motions), transitions between minima (interminimum motions), and relaxations in different hierarchical energy levels are investigated and compared with those encountered in vacuum by using different sampling window sizes and intervals. The low-frequency low-indexed mode relationship, established in vacuum, is also encountered in water, which shows the reliability of the important dynamics information offered by principal components analysis in water. It has been shown that examining a short data collection period (100ps) may result in a high population of overdamped modes, while some of the low-frequency oscillations (<10cm-1) can be captured in water by using a longer data collection period (1200ps). Simultaneous analysis of short and long sampling window sizes gives the following picture of the effect of water on protein dynamics. Water makes the protein lose its memory: future conformations are less dependent on previous conformations due to the lowering of energy barriers in hierarchical levels of the energy landscape. In short-time dynamics (<10ps), damping factors extracted from time series model parameters are lowered. For tendamistat, the friction coefficient in the Langevin equation is found to be around 40-60cm-1 for the low-indexed modes, compatible with literature. The fact that water has increased the friction and that on the other hand has lubrication effect at first sight contradicts. However, this comes about because water enhances the transitions between minima and forces the protein to reduce its already inherent inability to maintain oscillations observed in vacuum. Some of the frequencies lower than 10cm-1 are found to be overdamped, while those higher than 20cm-1 are slightly increased. As for the long-time dynamics in water, it is found that random-walk motion is maintained for approximately 200ps (about five times of that in vacuum) in the low-indexed modes, showing the lowering of energy barriers between the higher-level minima.

Determination of the refractive index of microparticles by utilizing light dispersion properties of the particle and an immersion liquid.

PubMed

Niskanen, I; Räty, J; Peiponen, K E

2013-10-15

The knowledge of the refractive index of a particle is important in sensing and imaging applications, e.g., in biology, medicine and process industry. The refractive index of tiny solid particles such as microsize particles can be determined by the so-called liquid immersion technique. This study deals with three different types of interrogation methods to get the refractive index of a particle in a liquid matrix. These methods utilize thermo-optical properties and wavelength-dependent refractive index of the particle and the immersion liquids, as well as, the classical method using a set of in advance prepared set of immersion liquids with different refractive indices. The emphasis is on a method to get especially the wavelength-dependent refractive index of microparticles and exploiting different wavelength-dependences of immersion liquid and a solid particle because identification of a particle is more reliable if the refractive index of the particle is known at several wavelengths. In this study glycerol-water mixtures served as immersion liquids to obtain the refractive index of CaF2 at several discrete wavelengths in the spectral range 200-500 nm. The idea is to find the maximum value of light transmission of suspension by scanning the wavelength of a commercial spectrophotometer. The light dispersion-based method is suggested as a relatively easy, economic and fast method to determine the refractive index of a particle by a spectrophotometer at several wavelengths of light. The accuracy of the detection of the refractive index is suggested to be better than ± 0.005 refractive index units. © 2013 Elsevier B.V. All rights reserved.

Taxocoenosis and distribution of nektonic fauna in the rice fields of Kashmir (J and K) India.

PubMed

Bahaar, S W N; Bhat, G A

2011-04-15

Present study attempts to identify the taxocoenosis and distribution of nektonic fauna harbouring the rice field ecosystems of Kashmir. The main objective of the study was to provide an overview of the nektonic community composition and physicochemical characteristics of flood waters. 6 sites were selected in Kupwara, Bandipora, Budgam, Srinagar, Pulwama and Anantnag districts of valley Kashmir. A total of 26 taxa belonging to 13 different orders were reported during the study which commenced through 2 consecutive crop cycles. The taxocoenosis was dominated by Coleoptera (10 taxa) followed by Hemiptera (3 taxa), Diptera (2 taxa), Diplostraca (2 taxa), Acarina, Anostraca, Anura, Amphipoda, Basommatophora, Cypriniformes, Cyprinodontiformes, Odonata and Pulmonata (1 taxa each). Diversity was calculated using Simpsons Index (D), Simpsons Index of Diversity (1-D), Simpsons Reciprocal Index (1/D), Shannon-Weiner Index (H'), Margalef Richness Index (d) and Evenness Index (e). Kupwara (34 degrees 02'N; 74 degrees 16'E) formed the most diverse site registering a total of 2384 individuals belonging to 24 taxa. A perusal of the primary data related to the physicochemical attributes of flood waters exhibited that average water temperature varied between 19-30 degrees C, average air temperature varied between 21 and 33 degrees C. pH depicted a variation between 6.0 and 9.0, Dissolved Oxygen varied between a minimum of 1.0 mg L(-1) and a maximum of 10 mg L(-1). Free CO2 ranged between 0 mg L(-1) and 6.1 mg(-1). The results pressed the need for recognizing and preserving rice fields as potential habitats for organisms that have successfully adapted to the highly manipulated and eutrophic conditions of rice paddies.

Determination of the refractive index of glucose-ethanol-water mixtures using spectroscopic refractometry near the critical angle.

PubMed

Sobral, H; Peña-Gomar, M

2015-10-01

A spectroscopic refractometer was used to investigate the dispersion curves of ethanol and D-glucose solutions in water near the critical angle; here, the reflectivity was measured using a white source. Dispersion curves were obtained in the 320-1000 nm wavelength range with a resolution better than 10(-4) for the refractive index, n. The differential refractive index is measured as a function of wavelength, and a simple expression is proposed to obtain the refractive index of the glucose-ethanol-water ternary system. Using this expression, combined with the experimental differential refractive index values, the concentrations of individual components can be calculated.

Water quality, hydrology, and the effects of changes in phosphorus loading to Pike Lake, Washington County, Wisconsin, with special emphasis on inlet-to-outlet short-circuiting

USGS Publications Warehouse

Rose, William J.; Robertson, Dale M.; Mergener, Elizabeth A.

2004-01-01

Simulations using water-quality models within the Wisconsin Lake Model Suite (WiLMS) indicated Pike Lake's response to 13 different phosphorus-loading scenarios. These scenarios included a base 'normal' year (2000) for which lake water quality and loading were known, six different percentage increases or decreases in phosphorus loading from controllable sources, and six different loading scenarios corresponding to specific management actions. Model simulations indicate that a 50-percent reduction in controllable loading sources would be needed to achieve a mesotrophic classification with respect to phosphorus, chlorophyll a, and Secchi depth (an index of water clarity). Model simulations indicated that short-circuiting of phosphorus from the inlet to the outlet was the main reason the water quality of the lake is good relative to the amount of loading from the Rubicon River and that changes in the percentage of inlet-to-outlet short-circuiting have a significant influence on the water quality of the lake.

Suitability Evaluation on River Bank Filtration of the Second Songhua River, China

NASA Astrophysics Data System (ADS)

Wang, Lixue; Ye, Xueyan; Du, Xinqiang

2016-04-01

The Second Songhua River is the biggest river with the most economic value in Jilin Province, China. In recent years, with the rapid development of economy, water resources and water environment problem is getting prominent, including surface water pollution and over exploitation of groundwater resources, etc. By means of bank filtration, the Second Songhua River basin might realize the combined utilization of regional groundwater and surface water, and thus has important significance for the guarantee of water demand for industrial and agricultural production planning in the basin. The following steps were adopted to evaluate the suitability of bank filtration nearby the Scond Songhua River : Firstly, in order to focus on the most possible area, the evaluation area was divided based on the aspects of natural geographical conditions and hydraulic connection extent between river water and groundwater. Second, the main suitability indexes including water quantity, water quality, interaction intensity between surface water and groundwater, and the exploitation condition of groundwater resource, and nine sub-indexes including hydraulic conductivity, aquifer thickness, river runoff, the status of groundwater quality, the status of surface water quality, groundwater hydraulic gradient, possible influence zone width of surface water under the condition of groundwater exploitation, permeability of riverbed layer and groundwater depth were proposed to establish an evaluation index system for the suitability of river bank filtration. Thirdly, Combined with the natural geography, geology and hydrogeology conditions of the Second Songhua River basin, the ArcGIS technology is used to complete the evaluation of the various indicators. According to the weighted sum of each index, the suitability of river bank filtration in the study area is divided into five grades. The evaluation index system and evaluation method established in this article are applicable to the Second Songhua River basin, which have clear pertinence and limitation. For future generalization of the evaluation index system, the specific evaluation index and its scoring criteria should be modified appropriately based on local conditions.

Development and Application of a Taiwan Domestic Generalized Water Supply Model

NASA Astrophysics Data System (ADS)

Ho, C. C.; Chang, L. C.

2016-12-01

Water allocation in Taiwan is more complicated than other countries because high river turbidity caused by rainstorm, reservoir management governed by different organization and conjunctive use of inter-basin reservoirs and dams. Those properties cause water resource planners need make extra effort on developing customized model to simulate the impact of water supply strategies on water resources. Hence, the study develops a Generalized Water Supply Model (GWSM) to analysis Multi-reservoirs water allocation in Taiwan for advancing the planning process. The model has following functions: (1) considering reservoirs operating rule curve. (2) considering the rule of multi-reservoir operation. Such as setting supply priority of different reservoirs or using "index balance" rule. (3) considering optimal hydroelectric power operation. (4) estimating the impact of high river turbidity on water supply. (5) considering the supply priority of different water use. (6) considering irrigation supply under special constraint. Such as the maximum irrigation supply is subject to natural inflow without reservoir storage. (7) considering two-way conduit transport. (8) considering environmental flow reservation. Conjunctive use Taan and Dajia Rivers was selected to demonstrate the ability of GWSM. The results also can be provided to different authorities to realize the impact of different strategies and that is good for negotiation and reaching a consensus.

Droughts in the US: Modeling and Forecasting for Agriculture-Water Management and Adaptation

NASA Astrophysics Data System (ADS)

Perveen, S.; Devineni, N.; Lall, U.

2012-12-01

More than half of all US counties are currently mired in a drought that is considered the worst in decades. A persistent drought can not only lead to widespread impacts on water access with interstate implications (as has been shown in the Southeast US and Texas), chronic scarcity can emerge as a risk in regions where fossil aquifers have become the primary source of supply and are being depleted at rates much faster than recharge (e.g., Midwestern US). The standardized drought indices on which the drought declarations are made in the US so far consider only the static decision frameworks—where only the supply is the control variable and not the water consumption. If a location has low demands, drought as manifest in the usual indices does not really have "proportionate" social impact. Conversely, a modest drought as indicated by the traditional measures may have significant impacts where demand is close to the climatological mean value of precipitation. This may also lead to drought being declared too late or too soon. Against this fact, the importance of improved drought forecasting and preparedness for different sectors of the economy becomes increasingly important. The central issue we propose to address through this paper is the construction and testing of a drought index that considers regional water demands for specific purposes (e.g., crops, municipal use) and their temporal distribution over the year for continental US. Here, we have highlighted the use of the proposed index for three main sectors: (i) water management organizations, (ii) optimizing agricultural water use, and (iii) supply chain water risk. The drought index will consider day-to-day climate variability and sectoral demands to develop aggregate regional conditions or disaggregated indices for water users. For the daily temperature and precipitation data, we are using NLDAS dataset that is available from 1949 onwards. The national agricultural statistics services (NASS) online database has been accessed for the agricultural data at the county level. Preliminary analyses show that large parts of Midwest and Southern parts of Florida and California are prone to multiyear droughts. This can primarily be attributed to high agricultural and/or urban water demands coupled with high interannual variability in supply. We propose to develop season-ahead and monthly updated forecasts of the drought index for informing the drought management plans. Given the already customized (sector specific) nature of the proposed drought index and its ability to represent the variability in both supply and demand, the early warning or forecasting of the index would not only complement the drought early warning systems in place by the national integrated drought information system (NIDIS) but also help in prescribing the ameliorative measures for adaptation.

Effects of cold plasma treatment on alfalfa seed growth under simulated drought stress

NASA Astrophysics Data System (ADS)

Jinkui, FENG; Decheng, WANG; Changyong, SHAO; Lili, ZHANG; Xin, TANG

2018-03-01

The effect of different cold plasma treatments on the germination and seedling growth of alfalfa (Medicago sativa L.) seeds under simulated drought stress conditions was investigated. Polyethyleneglycol-6000 (PEG 6000)with the mass fraction of 0% (purified water), 5%, 10%, and 15% were applied to simulate the drought environment. The alfalfa seeds were treated with 15 different power levels ranged between 0-280 W for 15 s. The germination potential, germination rate, germination index, seedling root length, seedling height, and vigor index were investigated. Results indicated significant differences between treated with proper power and untreated alfalfa seeds. With the increase of treatment power, these indexes mentioned above almost presented bimodal curves. Under the different mass fractions of PEG 6000, results showed that the lower power led to increased germination, and the seedlings presented good adaptability to different drought conditions. Meanwhile, higher power levels resulted in a decreased germination rate. Seeds treated with 40 W resulted in higher germination potential, germination rate, seedling height, root length, and vigor index. Vigor indexes of the treated seeds under different PEG 6000 stresses increased by 38.68%, 43.91%, 74.34%, and 39.20% respectively compared to CK0-0, CK5-0, CK10-0, and CK15-0 (the control sample under 0%, 5%, 10%, and 15% PEG 6000). Therefore, 40 W was regarded as the best treatment in this research. Although the trend indexes of alfalfa seeds treated with the same power were statistically the same under different PEG 6000 stresses, the cold plasma treatment had a significant effect on the adaptability of alfalfa seeds in different drought environments. Thus, this kind of treatment is worth implementing to promote seed growth under drought situations.

Stable and accurate methods for identification of water bodies from Landsat series imagery using meta-heuristic algorithms

NASA Astrophysics Data System (ADS)

Gamshadzaei, Mohammad Hossein; Rahimzadegan, Majid

2017-10-01

Identification of water extents in Landsat images is challenging due to surfaces with similar reflectance to water extents. The objective of this study is to provide stable and accurate methods for identifying water extents in Landsat images based on meta-heuristic algorithms. Then, seven Landsat images were selected from various environmental regions in Iran. Training of the algorithms was performed using 40 water pixels and 40 nonwater pixels in operational land imager images of Chitgar Lake (one of the study regions). Moreover, high-resolution images from Google Earth were digitized to evaluate the results. Two approaches were considered: index-based and artificial intelligence (AI) algorithms. In the first approach, nine common water spectral indices were investigated. AI algorithms were utilized to acquire coefficients of optimal band combinations to extract water extents. Among the AI algorithms, the artificial neural network algorithm and also the ant colony optimization, genetic algorithm, and particle swarm optimization (PSO) meta-heuristic algorithms were implemented. Index-based methods represented different performances in various regions. Among AI methods, PSO had the best performance with average overall accuracy and kappa coefficient of 93% and 98%, respectively. The results indicated the applicability of acquired band combinations to extract accurately and stably water extents in Landsat imagery.

Corrosiveness of ground water in the Kirkwood-Cohansey aquifer system of the New Jersey Coastal Plain

USGS Publications Warehouse

Barringer, J.L.; Kish, G.R.; Velnich, A.J.

1993-01-01

Ground water from the unconfined part of the Kirkwood-Cohansey aquifer system in the New Jersey Coastal Plain typically is corrosive-- that is, it is acidic, soft, and has low concentrations of alkalinity. Corrosive ground water has the potential to leach trace elements and asbestos fibers from plumbing materials used in potable- water systems, thereby causing potentially harmful concentrations of these substances in drinking water. Corrosion indices were calculated from water-quality data for 370 wells in the unconfined Kirkwood-Cohansey aquifer system. Values of the Langelier Saturation Index are predominantly negative, indicating that the water is undersaturated with respect to calcium carbonate, and, therefore, is potentially corrosive. Values of the Aggressive Index, a similar estimator of the corrosiveness of water, range from 3.9 (highly corrosive) to 11.9 (moderately corrosive). The median Aggressive Index value calculated for the 370 wells is 6.0, a value that indicates that the water is highly corrosive. Moderately corrosive ground water is found in some coastal areas. Isolated instances of moderately corrosive water are found in northern Ocean County, and in Burlington, Camden, and Salem Counties. In the vicinity of Ocean County corrosion-index values change little with depth, but in Atlantic, Burlington, and Salem Counties the corrosiveness of ground water generally appears to decrease with depth. Analyses of standing tap water from newly constructed homes in the Coastal Plain show concentrations of lead and other trace elements are significantly higher than those in ambient ground water. The elevated trace-element concentrations are attributed to the corrosion of plumbing materials by ground water. Results of the tap-water analyses substantiate the corrosiveness of Kirkwood-Cohansey ground water, as estimated by corrosion-index values.

Textural and sensory properties of trifoliate yam (Dioscorea dumetorum) flour and stiff dough 'amala'.

PubMed

Abiodun, O A; Akinoso, R

2015-05-01

The use of trifoliate yam (Dioscorea dumetorum) flour for stiff dough 'amala' production is one of the ways to curb under-utilization of the tuber. The study evaluates the textural and sensory properties of trifoliate yam flour and stiff dough. Freshly harvested trifoliate yam tubers were peeled, washed, sliced and blanched (60 (°)C for 10 min). The sliced yam were soaked in water for 12 h, dried and milled into flour. Pasting viscosities, functional properties, brown index and sensory attributes of the flour and stiff dough were analyzed. Peak, holding strength and final viscosities ranged from 84.09 to 213.33 RVU, 81.25 to 157.00 RVU and 127.58 to 236.17 RVU respectively. White raw flour had higher viscosity than the yellow flours. The swelling index, water absorption capacity and bulk density ranged from 1.46 to 2.28, 2.11 to 2.92 ml H2O/g and 0.71 to 0.88 g/cm(3) respectively. Blanching method employed improved the swelling index and water absorption capacity of flour. The brown index values of flour and stiff dough ranged from 6.73 to 18.36 and 14.63-46.72 respectively. Sensory evaluation revealed significant differences in the colour, odour and general acceptability of the product when compared with the stiff dough from white yam.

Interpreting drinking water quality in the distribution system using Dempster-Shafer theory of evidence.

PubMed

Sadiq, Rehan; Rodriguez, Manuel J

2005-04-01

Interpreting water quality data routinely generated for control and monitoring purposes in water distribution systems is a complicated task for utility managers. In fact, data for diverse water quality indicators (physico-chemical and microbiological) are generated at different times and at different locations in the distribution system. To simplify and improve the understanding and the interpretation of water quality, methodologies for aggregation and fusion of data must be developed. In this paper, the Dempster-Shafer theory also called theory of evidence is introduced as a potential methodology for interpreting water quality data. The conceptual basis of this methodology and the process for its implementation are presented by two applications. The first application deals with the interpretation of spatial water quality data fusion, while the second application deals with the development of water quality index based on key monitored indicators. Based on the obtained results, the authors discuss the potential contribution of theory of evidence as a decision-making tool for water quality management.

Hedging the financial risk from water scarcity for Great Lakes shipping

NASA Astrophysics Data System (ADS)

Meyer, Eliot S.; Characklis, Gregory W.; Brown, Casey; Moody, Paul

2016-01-01

Low water levels in the Great Lakes have recently had significant financial impacts on the region's commercial shipping, which transports hundreds of millions of dollars' worth of bulk goods each year. Cargo capacity is a function of a ship's draft, the distance between water level and the ship's bottom, and lower water levels force ships to reduce cargo loads to prevent running aground in shallow harbors and locks. Financial risk transfer instruments, such as index-based insurance contracts, may provide an adaptable method for managing these financial risks. In this work, a relationship between water levels and shipping revenues is developed and used in an actuarial analysis of the frequency and magnitude of revenue losses. This analysis is used to develop a standardized suite of binary financial contracts, which are indexed to water levels and priced according to predefined thresholds. These contracts are then combined to form hedging portfolios with different objectives for the shippers. Results suggest that binary contracts could substantially reduce the risk of financial losses during low lake level periods and at a relatively low cost of only one to three percent of total revenues, depending on coverage level.

Polar pollutants entry into the water cycle by municipal wastewater: a European perspective.

PubMed

Reemtsma, Thorsten; Weiss, Stefan; Mueller, Jutta; Petrovic, Mira; González, Susana; Barcelo, Damia; Ventura, Francesc; Knepper, Thomas P

2006-09-01

The effluents of eight municipal wastewater treatment plants (WWTP) in Western Europe were analyzed by liquid-chromatography-mass spectrometry for the occurrence of 36 polar pollutants, comprising household and industrial chemicals, pharmaceuticals, and personal care products. In a long-term study of the effluents of three WWTP over 10 months, sulfophenyl carboxylates and ethylene diamino tetraacetate (EDTA) were detected above 10 microg/L on average, while benzotriazoles, benzothiazole-2-sulfonate, diclofenac, and carbamazepine showed mean concentrations of 1-10 microg/L, followed by some flame retardants, naphthalene disulfonates, and personal care products in the range of 0.1-1 microg/L. Half of the determined compounds were not significantly removed in tertiary wastewater treatment. By dividing the effluent concentration of a compound by its relative removal in WWTP a water cycle spreading index (WCSI) was calculated for each compound. We propose that this index provides a measure for the potential of a polar compound to spread along a partially closed water cycle after discharge with municipal wastewater and to occur in raw waters used for drinking water production. Polar pollutants in surface water samples of different catchments showed increasing concentration for compounds with increasing WCSI.

Three-dimensional molecular mapping of a multiple emulsion by means of CARS microscopy.

PubMed

Meyer, Tobias; Akimov, Denis; Tarcea, Nicolae; Chatzipapadopoulos, Susana; Muschiolik, Gerald; Kobow, Jens; Schmitt, Michael; Popp, Jürgen

2008-02-07

Multiple emulsions consisting of water droplets dispersed in an oil phase containing emulsifier which is emulsified in an outer water phase (W/O/W) are of great interest in pharmacology for developing new drugs, in the nutrition sciences for designing functional food, and in biology as model systems for cell organelles such as liposomes. In the food industry multiple emulsions with high sugar content in the aqueous phase can be used for the production of sweets, because the high sugar content prevents deterioration. However, for these emulsions the refractive indexes of oil and aqueous phase are very similar. This seriously impedes the analysis of these emulsions, e.g., for process monitoring, because microscopic techniques based on transmission or reflection do not provide sufficient contrast. We have characterized the inner dispersed phase of concentrated W/O/W emulsions with the same refractive index of the three phases by micro Raman spectroscopy and investigated the composition and molecular distribution in water-oil-water emulsions by means of three-dimensional laser scanning CARS (coherent anti-Stokes Raman scattering) microscopy. CARS microscopy has been used to study water droplets dispersed in oil droplets at different Raman resonances to visualize different molecular species. Water droplets with a diameter of about 700 nm could clearly be visualized. The advantages of CARS microscopy for studying this particular system are emphasized by comparing this microscopic technique with conventional confocal reflection and transmission microscopies.

Extracting cross sections and water levels of vegetated ditches from LiDAR point clouds

NASA Astrophysics Data System (ADS)

Roelens, Jennifer; Dondeyne, Stefaan; Van Orshoven, Jos; Diels, Jan

2016-12-01

The hydrologic response of a catchment is sensitive to the morphology of the drainage network. Dimensions of bigger channels are usually well known, however, geometrical data for man-made ditches is often missing as there are many and small. Aerial LiDAR data offers the possibility to extract these small geometrical features. Analysing the three-dimensional point clouds directly will maintain the highest degree of information. A longitudinal and cross-sectional buffer were used to extract the cross-sectional profile points from the LiDAR point cloud. The profile was represented by spline functions fitted through the minimum envelop of the extracted points. The cross-sectional ditch profiles were classified for the presence of water and vegetation based on the normalized difference water index and the spatial characteristics of the points along the profile. The normalized difference water index was created using the RGB and intensity data coupled to the LiDAR points. The mean vertical deviation of 0.14 m found between the extracted and reference cross sections could mainly be attributed to the occurrence of water and partly to vegetation on the banks. In contrast to the cross-sectional area, the extracted width was not influenced by the environment (coefficient of determination R2 = 0.87). Water and vegetation influenced the extracted ditch characteristics, but the proposed method is still robust and therefore facilitates input data acquisition and improves accuracy of spatially explicit hydrological models.

[Effects of natural factors of Niska Banja spa on indexes of mobility of vertebral column in patients with ankylosing spondylitis].

PubMed

Nedović, Jovan; Stamenković, Bojana; Stojanović, Sonja; Stanković, Aleksandra; Dimić, Aleksandar

2009-01-01

Ankylosing spondilitis (AS) is a disease from a group of seronegative spondyloarthropathies with the prevalence of 0.1% affecting mainly young males, which also gives sociomedical significance to the disease. Among all inflammatory arthropathies, AS is the most suitable for balneotherapy. Thermomineral water of the Niska Banja spa is homeothermic, oligomineral, alkaline, low radioactive radon water and also, in conjunction with mineral peloid, is considered to be optimal for this indication. Our aim was to investigate the effects of natural factors of the Niska Banja spa as a part of complex treatment on the indexes of mobility of the vertebral column in the patients with AS. The study enrolled 40 patients with the average age of 48.0 +/-14.82 years and the average duration of disease of 16.9 +/- 6.42 years. Patients were treated with hydro- and peloidotherapy during the average of 17.23 +/- 2.71 days. At the beginning and at the end of treatment, a number of indexes of spinal mobility were measured. The statistical significance of differences was calculated using the Student's t-test. All of the measured indexes were better after balneotherapy reaching statistically significant differences in regard to the wall-to-occiput distance (p < 0.05), the index of sagittal mobility of the cervical (p < 0.05) and lumbar (p < 0.005) spine. The application of natural factors of the Niska Banja spa during complex treatment of the patients with AS is accompanied with the objective increase of the spine mobility.

Absolute Measurement of the Refractive Index of Water by a Mode-Locked Laser at 518 nm.

PubMed

Meng, Zhaopeng; Zhai, Xiaoyu; Wei, Jianguo; Wang, Zhiyang; Wu, Hanzhong

2018-04-09

In this paper, we demonstrate a method using a frequency comb, which can precisely measure the refractive index of water. We have developed a simple system, in which a Michelson interferometer is placed into a quartz-glass container with a low expansion coefficient, and for which compensation of the thermal expansion of the water container is not required. By scanning a mirror on a moving stage, a pair of cross-correlation patterns can be generated. We can obtain the length information via these cross-correlation patterns, with or without water in the container. The refractive index of water can be measured by the resulting lengths. Long-term experimental results show that our method can measure the refractive index of water with a high degree of accuracy-measurement uncertainty at 10 -5 level has been achieved, compared with the values calculated by the empirical formula.

Absolute Measurement of the Refractive Index of Water by a Mode-Locked Laser at 518 nm

PubMed Central

Meng, Zhaopeng; Zhai, Xiaoyu; Wei, Jianguo; Wang, Zhiyang; Wu, Hanzhong

2018-01-01

In this paper, we demonstrate a method using a frequency comb, which can precisely measure the refractive index of water. We have developed a simple system, in which a Michelson interferometer is placed into a quartz-glass container with a low expansion coefficient, and for which compensation of the thermal expansion of the water container is not required. By scanning a mirror on a moving stage, a pair of cross-correlation patterns can be generated. We can obtain the length information via these cross-correlation patterns, with or without water in the container. The refractive index of water can be measured by the resulting lengths. Long-term experimental results show that our method can measure the refractive index of water with a high degree of accuracy—measurement uncertainty at 10−5 level has been achieved, compared with the values calculated by the empirical formula. PMID:29642518

[Study on the hypoglycemic activity of different extracts of wild Psidium guajava leaves in Panzhihua Area].

PubMed

Wang, Bo; Liu, Heng-Chuan; Ju, Chang-Yan

2005-11-01

To illuminate the role of water-soluble, 650 ml/L edible alcohol and 950 ml/L edible alcohol-soluble extracts of wild Psidium guajava leaves in Panzhihua Area in decreasing blood glucose. High-level blood glucose models were made by use of male Kunming mice given intraperitoneal injection of glucose, subcutaneous injection of adrenaline and intraperitoneal injection of streptozotocin (STZ), respectively. Blood glucose concentration was measured after oral administration (gastrogavage) of the soluble extracts of Psidium guajava leaves, respectively. Body weight and organ morphology were observed, and organ index was obtained. The All available indexes were statistically analyzed in comparing the study groups and control group. three extracts resisted the rise of blood glucose level induced by exogenous glucose and adrenaline to various degrees. The extracts of water, 650 ml/L alcohol and 950 ml/L alcohol significantly decreased the blood glucose level in STZ-induced diabetic mice by 36.3%, 33.5% and 31.3% respectively. Furthermore, among three extracts, water-soluble extract showed little influence on the growth of mice. The water-soluble, 650 ml/L edible alcohol and 950 ml/L edible alcohol-soluble extracts of wild Psidium guajava leaves in Panzhihua area may have different hypoglycemic potential.

Hydrological modelling of the Mara River Basin, Kenya: Application of the Normalised Difference Infrared Index (NDII)

NASA Astrophysics Data System (ADS)

Hulsman, Petra; Savenije, Hubert; Bogaard, Thom

2017-04-01

In hydrology and water resources management, precipitation and discharge are the main time series for hydrological modelling. However, in African river catchments, the quantity and quality of the available precipitation stations and discharge measurements are unfortunately often inadequate for reliable hydrological modelling. To cope with these uncertainties, this study proposes to calibrate on water levels and to constrain the model using the Normalised Difference Infrared Index (NDII) as a proxy for root zone moisture stress. With the NDII, the leaf water content can be monitored. Previous studies related the NDII to the equivalent water thickness (EWT) of leaves, which is used to determine the vegetation water content (VWC). As the water content in the leaves is related to the water content in the root zone, the NDII can also be used as indicator of the soil moisture content in the root zone. In previous studies it was found that the root zone moisture content is exponentially correlated to the NDII during periods of moisture stress. In this study, the semi-distributed rainfall runoff model FLEX-Topo has been applied to the Mara River Basin. In this model seven sub-basins are distinguished and four hydrological response units with each a unique model structure based on the expected dominant flow processes. To calibrate the model, the water levels have been back-calculated from modelled discharges, using cross-section data and the Strickler formula calibrating parameter 'k•s1/2', and compared to measured water levels. In addition, the correlation between the NDII and root zone moisture content has been analysed for this river basin for each sub-catchment and hydrological response unit. Also, the application of the NDII as model constraint or for calibration has been analysed.

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 30, 1987.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

The Environmental Quality Instructional Resources Center acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. This publication contains abstracts and indexes to selected materials related…

Cyclic Steps and Antidunes : Relating Their Features to a Suspension Index

NASA Astrophysics Data System (ADS)

Yokokawa, M.; Kishima, Y.; Parker, G.

2010-12-01

Cyclic Steps and Antidunes : Relating Their Features to a Suspension Index Miwa Yokokawa (1), Yasushi Kishima (1), Gary Parker (2, 3) 1: Osaka Institute of Technology, Hirakata, Osaka, Japan 2: Dept. of Civil & Environmental Engineering, University of Illinois, Urbana, Illinois, U.S.A. 3: Dept. of Geology, University of Illinois, Urbana, Illinois, U.S.A. There are very few comparative studies of the differences in hydraulic conditions and morphologic features of bed- and water-surface-waves associated with cyclic steps and antidunes. In this study, the features of both the bed and the water surface, as well as hydraulic conditions are examined over the spectrum from antidune to cyclic steps. Experiments were performed using a flume at the Osaka Institute of Technology. The resultant features of the bedforms are as follows. In the case of antidunes, bed waves and water surface waves are in phase except when they collapse. Antidunes show several kinds of behavior; migrating downstream, standing, or migrating upstream. Upstream-migrating antidunes are divided into non-breaking, and breaking-types. Breaking antidunes appear alternatively with the plane bed state. Cyclic steps migrate upstream regularly associated with trains of hydraulic jumps, which divide each step. There is a significant change in water depth at the hydraulic jump, so that the phasing between the bed waves and water surface waves break at the each hydraulic jump. There is a kind of compromise between cyclic steps and antidunes, which we designate as “intermediate steps”. They move upstream and are associated with regular trains of hydraulic jumps. The jumps, however, occasionally collapse toward upstream. When this happens, bed waves move rapidly upstream; low-amplitude water surface waves and bed waves become in phase all over the bed shortly after the collapse. Then after some time, water surface waves become sufficiently prominent to yield regular hydraulic jumps. This cycle is then repeated.The hydraulic conditions for these bedfoms were examined using three non-dimensional parameters, i.e. the Froude Number, the Suspension Index, and the dimensionless particle size. The suspension index is a newly introduced parameter which is the ratio of the shear velocity divided by the settling velocity of the sediment (u*/Vs). Data from previous experimental studies are examined together with the present data in studying the characteristic regimes of bedform formation. In a diagram of Froude Number v.s. Suspension Index, antidunes, intermediate steps and cyclic steps can be divided along the axis of the Suspension Index. In the lowest range of the suspension index, downstream-migrating antidunes and upstream-migrating antidunes that do not break are found. The intermediate steps discussed above are located in the middle range. The highest range corresponds to cyclic steps and breaking antidunes. As described above, the Suspension Index can serve as a scale to quantify the spectrum between antidunes and cyclic steps. The use of the parameter also helps verify that suspension plays an important role in the formation and maintenance of cyclic steps.

An evaluation index system of water security in China based on macroeconomic data from 2000 to 2012

NASA Astrophysics Data System (ADS)

Li, X. S.; Peng, Z. Y.; Li, T. T.

2016-08-01

This paper establishes an evaluation index system of water security. The index system employs 5 subsystems (water circulation security, water environment security, water ecology security, water society security and water economy security) and has 39 indicators. Using the AHP method, each indicator is given a relative weight to integrate within the whole system. With macroeconomic data from 2000 to 2012, a model of water security evaluation is applied to assess the state of water security in China. The results show an improving trend in the overall state of China's water security. In particular, the cycle of water security is at a high and low fluctuation. Water environment security presents an upward trend on the whole; however, this trend is unsteady and has shown a descending tendency in some years. Yet, water ecology security, water society security, and water economy security are basically on the rise. However, the degree of coordination of China's water security system remains in need of consolidation.

Automatic Indexing for Content Analysis of Whale Recordings and XML Representation

NASA Astrophysics Data System (ADS)

Bénard, Frédéric; Glotin, Hervé

2010-12-01

This paper focuses on the robust indexing of sperm whale hydrophone recordings based on a set of features extracted from a real-time passive underwater acoustic tracking algorithm for multiple whales using four hydrophones. Acoustic localization permits the study of whale behavior in deep water without interfering with the environment. Given the position coordinates, we are able to generate different features such as the speed, energy of the clicks, Inter-Click-Interval (ICI), and so on. These features allow to construct different markers which allow us to index and structure the audio files. Thus, the behavior study is facilitated by choosing and accessing the corresponding index in the audio file. The complete indexing algorithm is processed on real data from the NUWC (Naval Undersea Warfare Center of the US Navy) and the AUTEC (Atlantic Undersea Test & Evaluation Center-Bahamas). Our model is validated by similar results from the US Navy (NUWC) and SOEST (School of Ocean and Earth Science and Technology) Hawaii university labs in a single whale case. Finally, as an illustration, we index a single whale sound file using the extracted whale's features provided by the tracking, and we present an example of an XML script structuring it.

Water-quality and lake-stage data for Wisconsin Lakes, water year 2003

USGS Publications Warehouse

Rose, W.J.; Garn, H.S.; Goddard, G.L.; Olson, D.L.; Robertson, Dale M.

2004-01-01

Water-resources data, including stage and discharge data at most streamflow-gaging stations, are available throught the World Wide Web on the Internet. The Wisconsin District's home page is at http://wi.water.usgs.gov/. Information on the Wisconsin District's Lakes Program is found at wi.water.usgs.gov/lake/index.html and wi.water.usgs.gov/projects/ index.html.

Using the Method of Water Poverty Index (WPI) to Evaluate the Region Water Security

NASA Astrophysics Data System (ADS)

Fu, Q.; Kachanoski, G.

2008-12-01

Water security is a widely concerned issue in the world nowadays. A new method, water poverty index (WPI), has been used to evaluate the regional water security. Twelve state farms in Heilongjiang Province, Northeastern China were selected to evaluate water security status based on the data of 2006 by using WPI and mean deviation grading method. The method of WPI includes five key indexes, such as resources(R), access (A), capacity(C), utilization (U) and environment (E). Each key index includes several sub-indexes. According to the results of WPI, the grade of each farm has been calculated by using the method of mean deviation grading. Thus, the radar images can be protracted of each farm. From the radar images, the conclusions can be drawn that the WPI values of Farms 853 and Hongqiling were in very safe status, while that of Farm Raohe was in safe status, those of Farms Youyi, 597, 852, 291 and Jiangchuan were in moderate safe status, that of Farm Beixing was in low safe status and those of Farms Shuangyashan, Shuguang and Baoshan were in unsafe status. The results from this study can provide basic information for decision making on rational use of water resources and regulations for regional water safety guarantee system.

The influence of climate regime shifts on the marine environment and ecosystems in the East Asian Marginal Seas and their mechanisms

NASA Astrophysics Data System (ADS)

Kun Jung, Hae; Rahman, SM Mustafizur; Kang, Chang-Keun; Park, Se-Young; Heon Lee, Sang; Je Park, Hyun; Kim, Hyun-Woo; Il Lee, Chung

2017-09-01

Step changes to seawater temperature (SWT) in the East Asian marginal seas (EAMS) are associated with three recent climate regime shifts (CRS) occurring in the mid-1970s, late 1980s, and late 1990s, but the responses of the ocean conditions and marine ecosystems had regional differences. A step change in SWT in the East China Sea (ECS) was detected after the CRS of the 1970s as were step changes in the North Pacific Index (NPI), Pacific Decadal Oscillation Index (PDOI), and East Asian Winter Monsoon Index (EAWMI). SWT in the ECS decreased with decreasing warm water volume transport into the EAMS and a strong monsoon, but step changes in SWT in other regions were not detected as clearly. After the CRS of the 1980s, SWT in all EAMS increased rapidly with step changes detected in all five climate indices examined. These changes were associated with a weak winter monsoon, increasing surface air temperature (SAT), and increasing warm water volume transport into the EAMS. However, after the CRS of the 1990s, a decrease in SWT around the EAMS was detected in the northern part of East China Sea (NECS), and the ECS with step changes also in the EAWMI and the Arctic Oscillation Index (AOI). In contrast, SWT in the East Sea/Sea of Japan (EJS) and the Yellow Sea (YS) continuously increased during this time. Long-term changes in zooplankton biomass were affected by regional differences in the responses of atmospheric and oceanic variability to CRSs. Specifically, long-term changes in the timing of peaks in zooplankton abundances exhibited differences. During warm periods (e.g. after the 1980s CRS) in the EJS, the amount of zooplankton biomass in October increased, while in February it decreased. On the contrary, in the YS and the NECS, the peaks of October and June in zooplankton biomass occurred during cold periods (after the 1970s and 1990s CRS). Major fisheries resources also responded to the three CRSs, although warm and cold water species responded differently to changes in oceanographic conditions in regional spawning grounds.

Assessment and hydro-geochemical characterization for evaluation of corrosion and scaling potential of groundwater in South West Delhi, India.

PubMed

Acharya, Sanigdha; Sharma, S K; Khandegar, Vinita

2018-06-01

In the present study, hydro-geochemical characteristics of groundwater samples collected from South West Delhi, India, have been assessed. 50 sampling locations were recorded with the help of global positioning system, to assess the groundwater quality and evaluate the corrosion and scaling potential. Hydro-geochemical characterization for different parameters such as pH, temperature (T), electrical conductivity (EC), total dissolved solids (TDS), salinity (SA), total hardness (TH), total alkalinity ( H C O 3 - ), levels of anions such as calcium (Ca +2 ), magnesium (Mg +2 ), sodium (Na + ), potassium (K + ) and cations which include chloride (Cl - ), Flouride (F - ), sulfates ( S O 4 - 2 ), Nitrates ( N O 3 - ) was done using standard APHA methods. The corrosion and scaling potential of groundwater was evaluated by five stability indices: Langelier saturation index (LSI), Ryznar stability index (RSI), Aggressive index (AI), Learson-Skold index (Ls) and Puckorius scaling index (PSI). The dataset classified groundwater as polluted and this indicates that the water is not safe for domestic, agricultural and industrial usage and will need further treatment. This dataset is beneficial for policymakers, and researchers in the field of water purification, quality management and in preventing the economic and safety concerns related to corrosion and scaling of groundwater.

Performance evaluation of different filter media in turbidity removal from water by application of modified qualitative indices.

PubMed

Gholikandi, G Badalians; Dehghanifard, E; Sepehr, M Noori; Torabian, A; Moalej, S; Dehnavi, A; Yari, Ar; Asgari, Ar

2012-01-01

Water filtration units have been faced problems in water turbidity removal related to their media, which is determined by qualitative indices. Moreover, Current qualitative indices such as turbidity and escaping particle number could not precisely determine the efficiency of the media in water filtration, so defining new indices is essential. In this study, the efficiency of Anthracite-Silica and LECA-Silica media in turbidity removal were compared in different operating condition by using modified qualitative indices. The pilot consisted of a filter column (one meter depth) which consisted of a layer of LECA (450 mm depth) and a layer of Silica sand (350 mm depth. Turbidities of 10, 20, and 30 NTU, coagulant concentrations of 4, 8, and 12 ppm and filtration rates of 10, 15, and 20 m/h were considered as variables. The LECA-Silica media is suitable media for water filtration. Averages of turbidity removal efficiencies in different condition for the LECA-Silica media were 85.8±5.37 percent in stable phase and 69.75±3.37 percent in whole operation phase, while the efficiency of total system were 98.31±0.63 and 94.49±2.97 percent, respectively. The LECA layer efficiency in turbidity removal was independent from filtration rates and due to its low head loss; LECA can be used as a proper medium for treatment plants. Results also showed that the particle index (PI) was a suitable index as a substitute for turbidity and EPN indices.

Application of the Water Needs Index: Can Tho City, Mekong Delta, Vietnam

NASA Astrophysics Data System (ADS)

Moglia, Magnus; Neumann, Luis E.; Alexander, Kim S.; Nguyen, Minh N.; Sharma, Ashok K.; Cook, Stephen; Trung, Nguyen H.; Tuan, Dinh D. A.

2012-10-01

SummaryProvision of urban water supplies to rapidly growing cities of South East Asia is difficult because of increasing demand for limited water supplies, periodic droughts, and depletion and contamination of surface and groundwater. In such adverse environments, effective policy and planning processes are required to secure adequate water supplies. Developing a Water Needs Index reveals key elements of the complex urban water supply by means of a participatory approach for rapid and interdisciplinary assessment. The index uses deliberative interactions with stakeholders to create opportunities for mutual understanding, confirmation of constructs and capacity building of all involved. In Can Tho City, located at the heart of the Mekong delta in Vietnam, a Water Needs Index has been developed with local stakeholders. The functional attributes of the Water Needs Index at this urban scale have been critically appraised. Systemic water issues, supply problems, health issues and inadequate, poorly functioning infrastructure requiring attention from local authorities have been identified. Entrenched social and economic inequities in access to water and sanitation, as well as polluting environmental management practices has caused widespread problems for urban populations. The framework provides a common language based on systems thinking, increased cross-sectoral communication, as well as increased recognition of problem issues; this ought to lead to improved urban water management. Importantly, the case study shows that the approach can help to overcome biases of local planners based on their limited experience (information black spots), to allow them to address problems experienced in all areas of the city.

Determination of reversed-phase high performance liquid chromatography based octanol-water partition coefficients for neutral and ionizable compounds: Methodology evaluation.

PubMed

Liang, Chao; Qiao, Jun-Qin; Lian, Hong-Zhen

2017-12-15

Reversed-phase liquid chromatography (RPLC) based octanol-water partition coefficient (logP) or distribution coefficient (logD) determination methods were revisited and assessed comprehensively. Classic isocratic and some gradient RPLC methods were conducted and evaluated for neutral, weak acid and basic compounds. Different lipophilicity indexes in logP or logD determination were discussed in detail, including the retention factor logk w corresponding to neat water as mobile phase extrapolated via linear solvent strength (LSS) model from isocratic runs and calculated with software from gradient runs, the chromatographic hydrophobicity index (CHI), apparent gradient capacity factor (k g ') and gradient retention time (t g ). Among the lipophilicity indexes discussed, logk w from whether isocratic or gradient elution methods best correlated with logP or logD. Therefore logk w is recommended as the preferred lipophilicity index for logP or logD determination. logk w easily calculated from methanol gradient runs might be the main candidate to replace logk w calculated from classic isocratic run as the ideal lipophilicity index. These revisited RPLC methods were not applicable for strongly ionized compounds that are hardly ion-suppressed. A previously reported imperfect ion-pair RPLC method was attempted and further explored for studying distribution coefficients (logD) of sulfonic acids that totally ionized in the mobile phase. Notably, experimental logD values of sulfonic acids were given for the first time. The IP-RPLC method provided a distinct way to explore logD values of ionized compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

Risk Assessment and effect of Penicillin-G on bacterial diversity in drinking water

NASA Astrophysics Data System (ADS)

Wu, Qing; Zhao, Xiaofei; Peng, Sen; Wang, Lei; Zhao, Xinhua

2018-02-01

Penicillin-G was detected in drinking water by LC-MS/MS and the bacterial diversity was investigated by PCR and high-throughput sequencing. The results showed that bacteria community structure in drinking water has undergone major changes when added different concentrations of penicillin-G. The diversity index of each sample was calculated. The results showed that the total number and abundance of bacterial community species in drinking water samples decreased significantly after the addition of penicillin-G. However, the number and abundance of community structure did not change with the concentration. Penicillin-G inhibits the activity of bacterial community in drinking water and can reduce the bacterial diversity in drinking water.

Regional estimation of base recharge to ground water using water balance and a base-flow index.

PubMed

Szilagyi, Jozsef; Harvey, F Edwin; Ayers, Jerry F

2003-01-01

Naturally occurring long-term mean annual base recharge to ground water in Nebraska was estimated with the help of a water-balance approach and an objective automated technique for base-flow separation involving minimal parameter-optimization requirements. Base recharge is equal to total recharge minus the amount of evapotranspiration coming directly from ground water. The estimation of evapotranspiration in the water-balance equation avoids the need to specify a contributing drainage area for ground water, which in certain cases may be considerably different from the drainage area for surface runoff. Evapotranspiration was calculated by the WREVAP model at the Solar and Meteorological Surface Observation Network (SAMSON) sites. Long-term mean annual base recharge was derived by determining the product of estimated long-term mean annual runoff (the difference between precipitation and evapotranspiration) and the base-flow index (BFI). The BFI was calculated from discharge data obtained from the U.S. Geological Survey's gauging stations in Nebraska. Mapping was achieved by using geographic information systems (GIS) and geostatistics. This approach is best suited for regional-scale applications. It does not require complex hydrogeologic modeling nor detailed knowledge of soil characteristics, vegetation cover, or land-use practices. Long-term mean annual base recharge rates in excess of 110 mm/year resulted in the extreme eastern part of Nebraska. The western portion of the state expressed rates of only 15 to 20 mm annually, while the Sandhills region of north-central Nebraska was estimated to receive twice as much base recharge (40 to 50 mm/year) as areas south of it.

Toxicity assessment of multi-walled carbon nanotubes on Cucurbita pepo L. under well-watered and water-stressed conditions.

PubMed

Hatami, Mehrnaz

2017-08-01

The rapid increase in the production and application of various types of nanomaterials increases the possibility of their presence in total environment, which subsequently raises concerns about their potential threats to the first trophic level of organisms, specifically under varying environmental constraints. In this work, seeds of Cucurbita pepo L. were cultured in MS basal medium exposed to multi-walled carbon nanotubes (MWCNTs) at different concentrations (0, 125, 250, 500 and 1000μgmL -1 ) under two levels of water potential, well-watered (0MPa) and water stress (-1.5MPa) induced by polyethylene glycol (PEG 6000) for 14 days. Seeds exposed to MWCNTs showed reduction in germination percentage, root and shoot length, biomass accumulation and vigor index in a dose-dependent manner. However, seedlings germinated in MWCNTs-fortified media had significantly lower germination and growth attributes than those of control under water stress conditions. This happened due to increased oxidative injury indices including hydrogen peroxide (H 2 O 2 ), and malondialdehyde (MDA) contents, as well as electrolyte leakage index (ELI) of tissues. The impaired morpho-physiological and biochemical processes of seedlings exposed to different concentrations of MWCNTs under both PEG-induced stress and non-stress growing conditions were consequence of changes in the activation of various cellular antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (POD). Taken together, our findings reveal that MWCNTs played negative role on seed germination and subsequent growth of C. pepo L. seedlings under both levels of water potential. Copyright © 2017 Elsevier Inc. All rights reserved.

A Water Temperature Simulation Model for Rice Paddies With Variable Water Depths

NASA Astrophysics Data System (ADS)

Maruyama, Atsushi; Nemoto, Manabu; Hamasaki, Takahiro; Ishida, Sachinobu; Kuwagata, Tsuneo

2017-12-01

A water temperature simulation model was developed to estimate the effects of water management on the thermal environment in rice paddies. The model was based on two energy balance equations: for the ground and for the vegetation, and considered the water layer and changes in the aerodynamic properties of its surface with water depth. The model was examined with field experiments for water depths of 0 mm (drained conditions) and 100 mm (flooded condition) at two locations. Daily mean water temperatures in the flooded condition were mostly higher than in the drained condition in both locations, and the maximum difference reached 2.6°C. This difference was mainly caused by the difference in surface roughness of the ground. Heat exchange by free convection played an important role in determining water temperature. From the model simulation, the temperature difference between drained and flooded conditions was more apparent under low air temperature and small leaf area index conditions; the maximum difference reached 3°C. Most of this difference occurred when the range of water depth was lower than 50 mm. The season-long variation in modeled water temperature showed good agreement with an observation data set from rice paddies with various rice-growing seasons, for a diverse range of water depths (root mean square error of 0.8-1.0°C). The proposed model can estimate water temperature for a given water depth, irrigation, and drainage conditions, which will improve our understanding of the effect of water management on plant growth and greenhouse gas emissions through the thermal environment of rice paddies.

Source apportionment and pollution evaluation of heavy metals in water and sediments of Buriganga River, Bangladesh, using multivariate analysis and pollution evaluation indices.

PubMed

Bhuiyan, Mohammad Amir Hossain; Dampare, Samuel B; Islam, M A; Suzuki, Shigeyuki

2015-01-01

Concentrations of heavy metals in water and sediment samples of Buriganga River in the capital city Dhaka, Bangladesh, were studied to understand the level of heavy metals and their source apportionment. The results showed that the mean concentrations of heavy metals both in water and sediment samples were very high and, in most cases, exceeded the permissible limits recommended by the Bangladesh government and other international organizations. Significantly higher concentrations of Pb, Cr, Mn, Co, Ni, Cu, Zn, As, and Cd were found in sediment samples. However, average concentrations of metals both in water and sediment samples were above the effect range median. The heavy metal pollution index (HPI) and degree of contamination (Cd) yielded different results in water samples despite significant correlations between them. The heavy metal evaluation index (HEI) showed strong correlations with HPI and Cd and provided better assessment of pollution levels. The enrichment factor (EF) and geoaccumulation index (Igeo) showed the elevated value of Cr, Pb, and Cd in access of background values. The measured elements were subjected to positive matrix factorization (PMF) and examining correlations in order to explain the content, behavior, and source apportionment of metals. PMF resulted in a successful partitioning of variances into sources related to background geochemistry and contaminant influences. However, the PMF approach successfully demarcated the major sources of metals from tannery, paint, municipal sewage, textiles, and agricultural activities.

Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index

PubMed Central

Li, Zheng; Zhou, Tao; Zhao, Xiang; Huang, Kaicheng; Gao, Shan; Wu, Hao; Luo, Hui

2015-01-01

Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI). We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI), from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months). When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation’s responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April–October). The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages. PMID:26184243

Relative water content of Spruce needles determined by the leaf water content index

NASA Technical Reports Server (NTRS)

Hunt, E. Raymond, Jr.; Wong, Sam K. S.; Rock, Barrett N.

1987-01-01

Leaf relative water content (RWC) is defined as the volume of water in a leaf divided by the volume at full turgor. Using reflectance factors of wavelengths 0.83 micron and 1.6 microns, a Leaf Water Content Index (LWCI) was derived from the Lambert-Beer Law such that LWCI should equal RWC; LWCI was equal to RWC for Picea pungens, Picea rubens, Liquidambar styraciflua, and Quercus agrifolia. Algebraic manipulation shows that R(1.6)/R(0.83) termed the Moisture Stress Index (MSI), is near-linearly correlated to RWC and to the Equivalent Water Thickness (EWT). Five species tested so far had the same relationship between MSI and EWT, but EWT is not a measure of plant water status.

[Spatial and temporal characteristics of flue-cured tobacco water requirement and irrigation requirement index in Yunnan Province, China].

PubMed

Zheng, Dong-fang; Xu, Jia-yang; Lu, Xiu-ping; Xu, Zi-cheng; Li, Jun-ying; Pang, Tao; Zhang, Ya-jie; Wang, Pei-wen

2015-07-01

Based on the daily meteorological data of 124 agricultural meteorological sites during 1977-2010 in Yunnan Province, using recommended Penman-Monteith formula by FAO, water requirement and irrigation requirement index in the growth period of flue-cured tobacco were calculated to analyze their spatial and temporal characteristics and change patterns. The results showed that water requirements of flue-cured tobacco in root extending, vigorous, mature periods and field growth period during 1977-2010 were 76.73-174.73, 247.50-386.64, 180.28-258.14 and 528.18-764.08 mm, respectively, and the water requirement of vigorous period was the highest. The average irrigation demand index of each period was -0.02, 0.38, 0.17 and 0.26, respectively. Effective precipitation could meet the demand of flue-cured tobacco in root extending period. Water requirement of flue-cured tobacco in Yunnan Province decreased annually, and the rates of water requirement under the climate change trend in the four periods abovementioned were -12. 42, -21.46, -7.17 and -47.15 mm . (10 a)-1, respectively. The smallest irrigation demand index was observed in Dehong, and the largest in Diqing. The irrigation demand indexes of Dehong, Xishuangbanna and Puer regions were negative in flue-cured tobacco field growth period. The reference crop evapotranspiration, water requirement and effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of latitude. The effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of altitude.

Community structure, phytoplankton density and physical-chemical factor of batang palangki waters of sijunjung regency, west sumatera

NASA Astrophysics Data System (ADS)

Gusmaweti; Deswati, L.

2018-03-01

The long-term goal of this study is to provide an overview of the presence of phytoplankton in support of its functions in the waters of Batang Palangki as a conservation area of information on river water management, especially for Batang Palangki stakeholders. Specific targets to be achieved in achieving these objectives are (1) to know the density of phytoplankton, index of diversity of species, equitabilty index, domination index, and in Batang Palangki waters, and (2) to analyze the chemical and physical factors of the waters. The sampling method of phytoplankton is purposive sampling. The phytoplankton sampling is done By filtering 100 liters of water into the net plankton no 25 and filtered into the 25 cc, and then identified. The determination of water quality such as water temperature, water pH and watercolour. dissolved oxygen (DO) and BOD, and Hg content (mercury). The results showed that phytoplankton found from each of station was 370 individualis per liter with the highest density found in the station I of 155. The number of genus was 7, namely Neidium, Gyrogsima, Synedra, Frustulia, Fragillaria, Nitzschia and Peridinium. The diversity index averaged at 0.45, equabilty index averaged at 0.54, while the dominance index averaged at 0.28. Physical and chemical factor measurement results found that water temperature averaged at 26 °C, transparency ranged from 12 - 30 cm, velocity speed ranged from 8 - 15 m/s, while chemical factors such as DO, BOD, and COD ranged from 5.25 to 5.96 mg/L, 3.28 - 3.49 mg/L, and 47.05 - 76.25 mg/L respectively. Likewise, TOM measured in this research was 9.61 - 2.10 mg/L while Hg content ranged from 0.098 - 0.208 mg/L.

Sources of variation in estimates of lean body mass by creatinine kinetics and by methods based on body water or body mass index in patients on continuous peritoneal dialysis.

PubMed

Tzamaloukas, Antonios H; Murata, Glen H; Piraino, Beth; Raj, Dominic S C; VanderJagt, Dorothy J; Bernardini, Judith; Servilla, Karen S; Sun, Yijuan; Glew, Robert H; Oreopoulos, Dimitrios G

2010-03-01

We identified factors that account for differences between lean body mass computed from creatinine kinetics (LBM(cr)) and from either body water (LBM(V)) or body mass index (LBM(BMI)) in patients on continuous peritoneal dialysis (CPD). We compared the LBM(cr) and LBM(V) or LBM(BMI) in hypothetical subjects and actual CPD patients. We studied 439 CPD patients in Albuquerque, Pittsburgh, and Toronto, with 925 clearance studies. Creatinine production was estimated using formulas derived in CPD patients. Body water (V) was estimated from anthropometric formulas. We calculated LBM(BMI) from a formula that estimates body composition based on body mass index. In hypothetical subjects, LBM values were calculated by varying the determinants of body composition (gender, diabetic status, age, weight, and height) one at a time, while the other determinants were kept constant. In actual CPD patients, multiple linear regression and logistic regression were used to identify factors associated with differences in the estimates of LBM (LBM(cr)LBM(V). The differences in determinants of body composition between groups with high versus low LBM(cr) were similar in hypothetical and actual CPD patients. Multivariate analysis in actual CPD patients identified serum creatinine, height, age, gender, weight, and body mass index as predictors of the differences LBM(V)-LBM(cr) and LBM(BMI)-LBM(cr). Overhydration is not the sole factor accounting for the differences between LBM(cr) and either LBM(V) or LBM(BMI) in CPD patients. These differences also stem from the coefficients assigned to major determinants of body composition by the formulas estimating LBM. Published by Elsevier Inc.

Potential Water Availability Index (PWAI): A New Water Vulnerability Index for Africa Based on GRACE Data

NASA Astrophysics Data System (ADS)

Hasan, E.; Tarhule, A.; Hong, Y.; Moore, B., III

2016-12-01

The critical role of water in enabling or constraining human wellbeing and socio-economic activities has led to interest in quantitatively establishing the status or index of water (in)sufficiency over time and space. Introduced in 1989, the first widely accepted index expressed the status of water resources availability in terms of vulnerability, stress, or scarcity. Since then, numerous refinements and modifications to the concept have been published but nearly all adopt the same basic formulation; water status is a function of available water resources and demand or use. However, accurately defining and assessing `available water' has proved problematic especially in data scarce regions, such as Africa. In this paper, we use Total Water Storage (TWS) estimated from NASA's Gravity Recovery and Climate Experiment (GRACE) in lieu of observational hydrologic data, to estimate the Water Scarcity Index (WSI) for Africa at country level. The monthly TWS Positive anomalies represent periods of net system recharge while negative anomalies represent net system loss due to evapotranspiration and anthropogenic withdrawals. The procedure is as follows. First, we calculated the long-term (2002-2014) Internal Water Storage (IWS) for each country using the monthly precipitation data from the Global Precipitation Climatology Centre (GPCC). Next, the yearly cumulative positive and negative anomalies were added to the long-term IWS to obtain volumetric Potential Water Storage (VPWS) per country. By dividing VPWS by population, we obtain estimates of per capita water availability which can be grouped into vulnerability classes using established thresholds. Our VPWS showed very high correlation (R2 =0.94, p=0.0001) with the values of Internal Renewable Water Resources (IRWR) estimated by AQUSTAT. Additionally, the GWSI is highly correlated (R2 =0.94, p=0.0001) with the existing WSI index from the world bank data center. The novelty and contribution of our approach is in using GRACE anomalies to efficiently estimate total available water, including groundwater which is at best poorly estimated and, frequently, completely ignored in conventional approaches due to absent or unreliable data. The available water estimated in this way represent the potential amount of water that could be theoretically exploited.

The Trapping Index: How to integrate the Eulerian and the Lagrangian approach for the computation of the transport time scales of semi-enclosed basins.

PubMed

Cucco, Andrea; Umgiesser, Georg

2015-09-15

In this work, we investigated if the Eulerian and the Lagrangian approaches for the computation of the Transport Time Scales (TTS) of semi-enclosed water bodies can be used univocally to define the spatial variability of basin flushing features. The Eulerian and Lagrangian TTS were computed for both simplified test cases and a realistic domain: the Venice Lagoon. The results confirmed the two approaches cannot be adopted univocally and that the spatial variability of the water renewal capacity can be investigated only through the computation of both the TTS. A specific analysis, based on the computation of a so-called Trapping Index, was then suggested to integrate the information provided by the two different approaches. The obtained results proved the Trapping Index to be useful to avoid any misleading interpretation due to the evaluation of the basin renewal features just from an Eulerian only or from a Lagrangian only perspective. Copyright © 2015 Elsevier Ltd. All rights reserved.

Deploying a Proximal Sensing Cart to Identify Drought-Adaptive Traits in Upland Cotton for High-Throughput Phenotyping

PubMed Central

Thompson, Alison L.; Thorp, Kelly R.; Conley, Matthew; Andrade-Sanchez, Pedro; Heun, John T.; Dyer, John M.; White, Jeffery W.

2018-01-01

Field-based high-throughput phenotyping is an emerging approach to quantify difficult, time-sensitive plant traits in relevant growing conditions. Proximal sensing carts represent an alternative platform to more costly high-clearance tractors for phenotyping dynamic traits in the field. A proximal sensing cart and specifically a deployment protocol, were developed to phenotype traits related to drought tolerance in the field. The cart-sensor package included an infrared thermometer, ultrasonic transducer, multi-spectral reflectance sensor, weather station, and RGB cameras. The cart deployment protocol was evaluated on 35 upland cotton (Gossypium hirsutum L.) entries grown in 2017 at Maricopa, AZ, United States. Experimental plots were grown under well-watered and water-limited conditions using a (0,1) alpha lattice design and evaluated in June and July. Total collection time of the 0.87 hectare field averaged 2 h and 27 min and produced 50.7 MB and 45.7 GB of data from the sensors and RGB cameras, respectively. Canopy temperature, crop water stress index (CWSI), canopy height, normalized difference vegetative index (NDVI), and leaf area index (LAI) differed among entries and showed an interaction with the water regime (p < 0.05). Broad-sense heritability (H2) estimates ranged from 0.097 to 0.574 across all phenotypes and collections. Canopy cover estimated from RGB images increased with counts of established plants (r = 0.747, p = 0.033). Based on the cart-derived phenotypes, three entries were found to have improved drought-adaptive traits compared to a local adapted cultivar. These results indicate that the deployment protocol developed for the cart and sensor package can measure multiple traits rapidly and accurately to characterize complex plant traits under drought conditions. PMID:29868041

A revisitation of TRIX for trophic status assessment in the light of the European Water Framework Directive: application to Italian coastal waters.

PubMed

Pettine, Maurizio; Casentini, Barbara; Fazi, Stefano; Giovanardi, Franco; Pagnotta, Romano

2007-09-01

The trophic status classification of coastal waters at the European scale requires the availability of harmonised indicators and procedures. The composite trophic status index (TRIX) provides useful metrics for the assessment of the trophic status of coastal waters. It was originally developed for Italian coastal waters and then applied in many European seas (Adriatic, Tyrrhenian, Baltic, Black and Northern seas). The TRIX index does not fulfil the classification procedure suggested by the WFD for two reasons: (a) it is based on an absolute trophic scale without any normalization to type-specific reference conditions; (b) it makes an ex ante aggregation of biological (Chl-a) and physico-chemical (oxygen, nutrients) quality elements, instead of an ex post integration of separate evaluations of biological and subsequent chemical quality elements. A revisitation of the TRIX index in the light of the European Water Framework Directive (WFD, 2000/60/EC) and new TRIX derived tools are presented in this paper. A number of Italian coastal sites were grouped into different types based on a thorough analysis of their hydro-morphological conditions, and type-specific reference sites were selected. Unscaled TRIX values (UNTRIX) for reference and impacted sites have been calculated and two alternative UNTRIX-based classification procedures are discussed. The proposed procedures, to be validated on a broader scale, provide users with simple tools that give an integrated view of nutrient enrichment and its effects on algal biomass (Chl-a) and on oxygen levels. This trophic evaluation along with phytoplankton indicator species and algal blooms contribute to the comprehensive assessment of phytoplankton, one of the biological quality elements in coastal waters.

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources materials. Supplement 31, 1987.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

The Environmental Quality Instructional Resources Center in Columbus, Ohio, acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. This publication contains abstracts and indexes to selected…

USING ENERGY AND EMERGY TO COUPLE GEOMORPHOLOGY AND HUMAN INFLUENCES INTO A WATERSHED/LANDSCAPE INDEX AND LINK THE INDEX TO DOWNSTREAM WATER AND HABITAT QUALITY

EPA Science Inventory

The Clean Water Act requires identification of all waters whose abiotic and biotic integrity have been compromised or impaired, but it is impossible to assess each water body in the nation. Although landscape studies attempting to find correlations between land use and water con...

Modeling seasonal changes in live fuel moisture and equivalent water thickness using a cumulative water balance index

Treesearch

Philip E. Dennison; Dar A. Roberts; Sommer R. Thorgusen; Jon C. Regelbrugge; David Weise; Christopher Lee

2003-01-01

Live fuel moisture, an important determinant of fire danger in Mediterranean ecosystems, exhibits seasonal changes in response to soil water availability. Both drought stress indices based on meteorological data and remote sensing indices based on vegetation water absorption can be used to monitor live fuel moisture. In this study, a cumulative water balance index (...

Study for determination of industrial water corrosivity in Kashan Fajre Sepahan Galvanizing Mills during 2005-2006 Iran.

PubMed

Rabbani, D; Miranzadeh, M B; Motlagh, A Ahmadi

2008-01-01

This research was carried out in Kashan Fajre Sepahan Galvanizing mills (KFSGM) for evaluation of water corrosivity during 2005-2006. A total of 18 samples were taken from various points of the water supply system for testing the specific parameters and calculation Langelier Index (LI), Ryznar Index (RI) and Pukorious Index (PI). This research showed that in raw water (sand filter effluent) LI were positive as well as RI and PI were lower than 7 which means that mentioned water is not corrosive. Also LI in treated water by reverse osmosis process was negative and RI and PI were higher than 7, so, this water has corrosive properties. Finally, calculated indexes indicate that according to LI, conditioned water is not corrosive but based on RI and P. this water tend to corrosivity which this findings is compatible with literature review statement. So it is recommended that, for water conditioning addition of preservative chemicals to be continued but at the same time another alternatives such as pH adjustment, air stripping and deoxygenating, control of carbonate concentration and split flow treatment should be studied.

Wheat Response to Differences In Water and Nutritional Status Between Zeoponic and Hydroponic Growth Systems

NASA Technical Reports Server (NTRS)

Steinberg, Susan L.; Ming, Douglas W.; Henderson, Keith E.; Carrier, Chris; Gruener, John E.; Barta, Dan J.; Henninger, Don L.

1999-01-01

Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L., CV 'USU-Apogee'). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15-20 L per square meters per d up to day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences were noted in water status between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT versus hydroponic culture. Sterile green tillers made up 12% and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4 -N nutrition of plants grown in ZPT as compared with NO3-N in hydroponic nutrient solution. It was likely that NH4-N induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.

Wheat response to differences in water and nutritional status between zeoponic and hydroponic growth systems

NASA Technical Reports Server (NTRS)

Steinberg, S. L.; Ming, D. W.; Henderson, K. E.; Carrier, C.; Gruener, J. E.; Barta, D. J.; Henninger, D. L.

2000-01-01

Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L. cv. USU-Apogee). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15 to 20 L m-2 d-1 up to Day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences in water status were noted between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT than in hydroponic culture. Sterile green tillers made up 12 and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4-N nutrition of plants grown in ZPT compared with NO3-N in hydroponic nutrient solution. It is probable that NH4-N-induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.

A Geographically Variable Water Quality Index Used in Oregon.

ERIC Educational Resources Information Center

Dunnette, D. A.

1979-01-01

Discusses the procedure developed in Oregon to formulate a valid water quality index which accounts for the specific conditions in the water body of interest. Parameters selected include oxygen depletion, BOD, eutrophication, dissolved substances, health hazards, and physical characteristics. (CS)

Contrasting Eutrophication Risks and Countermeasures in Different Water Bodies: Assessments to Support Targeted Watershed Management

PubMed Central

Li, Tong; Chu, Chunli; Zhang, Yinan; Ju, Meiting; Wang, Yuqiu

2017-01-01

Eutrophication is a major problem in China. To combat this issue, the country needs to establish water quality targets, monitoring systems, and intelligent watershed management. This study explores a new watershed management method. Water quality is first assessed using a single factor index method. Then, changes in total nitrogen/total phosphorus (TN/TP) are analyzed to determine the limiting factor. Next, the study compares the eutrophication status of two water function districts, using a comprehensive nutritional state index method and geographic information system (GIS) visualization. Finally, nutrient sources are qualitatively analyzed. Two functional water areas in Tianjin, China were selected and analyzed: Qilihai National Wetland Nature Reserve and Yuqiao Reservoir. The reservoir is a drinking water source. Results indicate that total nitrogen (TN) and total phosphorus (TP) pollution are the main factors driving eutrophication in the Qilihai Wetland and Yuqiao Reservoir. Phosphorus was the limiting factor in the Yuqiao Reservoir; nitrogen was the limiting factor in the Qilihai Wetland. Pollution in Qilihai Wetland is more serious than in Yuqiao Reservoir. The study found that external sources are the main source of pollution. These two functional water areas are vital for Tianjin; as such, the study proposes targeted management measures. PMID:28661417

[Scientific substantiation of perfection of sanitary bacteriological monitoring in drinking water use].

PubMed

Rakhmanin, Iu A; Zhuravlev, P V; Aleshnia, V V; Panasovets, O P; Artemova, T Z; Zagaĭnova, A V; Gipp, E K

2014-01-01

Criterion of the epidemic safety of drinking water is the absence of pathogenic and potentially pathogenic microorganisms. Currently, water quality control is performed in terms of the index of total coliform bacteria (TCB). TCB index oriented to the labile lactose sign has not sufficient relevance in the determination of the degree of the epidemic danger in the water use in relation to Salmonella and potentially pathogenic microorganisms. The frequency of detection of GCB in standard quality of drinking water as well as the application of the methodology for the assessment of the microbial risk of the occurrence of bacterial intestinal infections with the use of integral index--GCB, provide the most reliable prediction of risk in the occurrence of water-caused intestinal infections and more objectively reflect the epidemiological importance of drinking water in their distribution among the population. Proceeding from the data obtained, it is advisable to carry out the quality control of drinking water with the use of the broader indicator index GCB- detected from basic signs of the Enterobacteriaceae family--glucose fermentation and oxidase test and oxidase test.

Water use benefit index as a tool for community-based monitoring of water related trends in the Great Barrier Reef region

NASA Astrophysics Data System (ADS)

Smajgl, A.; Larson, S.; Hug, B.; De Freitas, D. M.

2010-12-01

SummaryThis paper presents a tool for documenting and monitoring water use benefits in the Great Barrier Reef catchments that allows temporal and spatial comparison along the region. Water, water use benefits and water allocations are currently receiving much attention from Australian policy makers and conservation practitioners. Because of the inherent complexity and variability in water quality, it is essential that scientific information is presented in a meaningful way to policy makers, managers and ultimately, to the general public who have to live with the consequences of the decisions. We developed an inexpensively populated and easily understandable water use benefit index as a tool for community-based monitoring of water related trends in the Great Barrier Reef region. The index is developed based on a comparative list of selected water-related indices integrating attributes across physico-chemical, economic, social, and ecological domains currently used in the assessment of water quality, water quantity and water use benefits in Australia. Our findings indicate that the proposed index allows the identification of water performance indicators by temporal and spatial comparisons. Benefits for decision makers and conservation practitioners include a flexible way of prioritization towards the domain with highest concern. The broader community benefits from a comprehensive and user-friendly tool, communicating changes in water quality trends more effectively.

Managing hydroclimatological risk to water supply with option contracts and reservoir index insurance

NASA Astrophysics Data System (ADS)

Brown, Casey; Carriquiry, Miguel

2007-11-01

This paper explores the performance of a system of economic instruments designed to facilitate the reduction of hydroclimatologic variability-induced impacts on stakeholders of shared water supply. The system is composed of bulk water option contracts between urban water suppliers and agricultural users and insurance indexed on reservoir inflows. The insurance is designed to cover the financial needs of the water supplier in situations where the option is likely to be exercised. Insurance provides the irregularly needed funds for exercising the water options. The combined option contract - reservoir index insurance system creates risk sharing between sectors that is currently lacking in many shared water situations. Contracts are designed for a shared agriculture - urban water system in Metro Manila, Philippines, using optimization and Monte Carlo analysis. Observed reservoir inflows are used to simulate contract performance. Results indicate the option - insurance design effectively smooths water supply costs of hydrologic variability for both agriculture and urban water.

A descriptive study on selected growth parameters and growth hormone receptor gene in healthy young adults from the American Midwest.

PubMed

Hartin, Samantha N; Hossain, Waheeda A; Manzardo, Ann M; Brown, Shaquanna; Fite, Paula J; Bortolato, Marco; Butler, Merlin G

2018-02-12

The first study of growth hormone receptor (GHR) genotypes in healthy young adults in the United States attending a Midwestern university and impact on selected growth parameters. To describe the frequency of GHR genotypes in a sample of healthy young adults from the United States attending a university in the Midwest and analyze the relationship between GHR genotypes and selected growth parameters. Saliva was collected from 459 healthy young adults (237 females, 222 males; age range = 18-25 y) and DNA isolated for genotyping of GHR alleles (fl/fl, fl/d3, or d3/d3). Selected growth parameters were collected and GHR genotype data examined for previously reported associations (e.g., height, weight or bone mass density) or novel findings (e.g., % body water and index finger length). We found 219 participants (48%) homozygous for fl/fl, 203 (44%), heterozygous fl/d3 and 37 (8%) homozygous d3/d3. The distribution of GHR genotypes in our participants was consistent with previous reports of non-US populations. Several anthropometric measures differed by sex. The distribution of GHR genotypes did not significantly differ by sex, weight, or other anthropometric measures. However, the fl/d3 genotype was more common among African-Americans. Our study of growth and anthropometric parameters in relationship to GHR genotypes found no association with height, weight, right index finger length, BMI, bone mass density, % body fat or % body water in healthy young adults. We did identify sex differences with increased body fat, decreased bone density, body water and index finger length in females. Copyright © 2018 Elsevier Ltd. All rights reserved.

Relationship between Hydrodynamic Conditions and Water Quality in Landscape Water Body

NASA Astrophysics Data System (ADS)

Kang, Mengxin; Tian, Yimei; Zhang, Haiya; Wang, Dehong

2018-01-01

The urban landscape water usually lacks necessary water cycle and water speed is closed to zero, which easily lead to eutrophication in water system and deterioration of water quality. Therefore, understanding the impact of water circulation on the water quality is of great significance. With that significance, this research has been done to investigate the relationship between hydrodynamic conditions and water quality of urban landscape water based on adopted water quality indexes such as chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and nitrogen-ammonia (NH3-N). Moreover, MIKE 21 model is used to simulate the hydrodynamics and water quality under different cases in an urban landscape lake. The results of simulation show that water circulation system could effectively improve current speeds, reduce the proportion of stagnation area, and solve the problem of water quality deterioration caused by reclaimed water in the lake.

Application of minidisk infiltrometer to estimate soil water repellency

NASA Astrophysics Data System (ADS)

Alagna, Vincenzo; Iovino, Massimo; Bagarello, Vincenzo; Mataix-Solera, Jorge; Lichner, Ľubomír

2016-04-01

Soil water repellency (SWR) reduces affinity of soils to water resulting in detrimental implication for plants growth as well as for hydrological processes. During the last decades, it has become clear that SWR is much more widespread than formerly thought, having been reported for a wide variety of soils, land uses and climatic conditions. The repellency index (RI), based on soil-water to soil-ethanol sorptivity ratio, was proposed to characterize subcritical SWR that is the situation where a low degree of repellency impedes infiltration but does not prevent it. The minidisk infiltrometer allows adequate field assessment of RI inherently scaled to account for soil physical properties other than hydrophobicity (e.g., the volume, connectivity and the geometry of pores) that directly influence the hydrological processes. There are however some issues that still need consideration. For example, use of a fixed time for both water and ethanol sorptivity estimation may lead to inaccurate RI values given that water infiltration could be negligible whereas ethanol sorptivity could be overestimated due to influence of gravity and lateral diffusion that rapidly come into play when the infiltration process is very fast. Moreover, water and ethanol sorptivity values need to be determined at different infiltration sites thus implying that a large number of replicated runs should be carried out to obtain a reliable estimate of RI for a given area. Minidisk infiltrometer tests, conducted under different initial soil moisture and management conditions in the experimental sites of Ciavolo, Trapani (Italy) and Javea, Alicante (East Spain), were used to investigate the best applicative procedure to estimate RI. In particular, different techniques to estimate the water, Sw, and ethanol, Se, sorptivities were compared including i) a fixed 1-min time interval, ii) the slope of early-time 1D infiltration equation and iii) the two-term transient 3D infiltration equation that explicitly accounts for the effects of gravity and lateral expansion. According to Pekárová et al. (2015), the combination of all the ethanol and water sorptivities was used to calculate an aggregated repellency index, RIa, that accounts for the influence of spatial variability. Alternatively, the plot of the water cumulative infiltration vs. square root of time, exhibiting a clear "hockey-stick-like" shape, was used to estimate a single-test repellency index, RI∗, that overcomes the limitations of the traditional approach given that information on both the hydrophobic and the wettable states of soil are gathered from a unique infiltration test. The mean RI values were affected by the technique used to estimate Sw and Se. In particular, the choice of a fixed time interval lead to overestimation of RI up to a factor of 3.2 as compared with the other techniques. The RIa yielded unbiased estimations of the mean RI values and also allowed to quantify the variability of SWR within a given area. A statistically significant relationship was found between RI∗ and RI but also between RI∗ and the water retention cessation time, that is the time hydrophobic turns into wettable soil, thus indicating that RI∗ is potentially able detect both the degree and the persistence of SWR. Pekárová P., Pekár J., Lichner Ľ. 2015. A new method for estimating soil water repellency index. Biologia, 70(11):1450-1455.

18 CFR 401.105 - Indexes of certain records.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Indexes of certain records. 401.105 Section 401.105 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL RULES OF PRACTICE AND PROCEDURE Public Access to Records and Information § 401.105 Indexes...

Assessment of water resources potential of Ceará state (Brazil)

NASA Astrophysics Data System (ADS)

Araujo, Angelo; Pereira, Diamantino; Pereira, Paulo

2016-04-01

A methodological approach and results on water resources assessment in large areas are described with the case study of Ceará State (148,016 km2, northeast Brazil), where the scarceness of water resources is one of the main challenges in territorial planning and development. This work deals with the quantification and the mapping of water resources potential, being part of methodological approaches applied to the quantification of hydric diversity and geodiversity. Water resources potential is here considered as the sum of the hydric elements rainfall, groundwater specific discharge, water reservoirs, and river hierarchy. The assessment was based in a territorial organization by drainage sub-basins and in vector maps generated and treated with GIS software. Rainfall, groundwater specific discharge and hydrographical data were obtained in official institutions and allowed the construction of the annual mean rainfall map for a forty year period (1974-2014), the annual mean groundwater specific discharge map for a thirty-four year period, and the river and drainage basin hierarchy maps. These delivered rainfall, groundwater specific discharge, water reservoirs and river hierarchy partial indices expressed on quantitative maps with normalized values distributed by level 3 drainage basins. The sum of the partial indices originated the quantitative map of water resources potential index and by the Gaussian interpolation of this quantitative data a map of hydric diversity in Ceará state was created. Therefore, the water resources potential index is higher in 4 regions of the state (Noroeste Cearense, Zona Metropolitana de Fortaleza e da Zona Norte, Vale do Jaguaribe and Zonas Centro-sul e Sul Cearense). The index is low or very low in the whole region of Sertões Cearenses, confirming the important role of climatic features in hydrological diversity. Water resources management must consider technical tools for water resources assessment, in the line of other methods for quantitative assessment of natural features either biotic or abiotic. These results quantify water resources and their distribution in a large region with important climatic differences. They constitute a basis for the knowledge of regional issues concerning water needs, flood and droughts events and even engineering solutions for water resources management.

DFT simulations of water adsorption and activation on low-index α-Ga2O3 surfaces.

PubMed

Zhou, Xin; Hensen, Emiel J M; van Santen, Rutger A; Li, Can

2014-06-02

Density functional theory (DFT) calculations are used to explore water adsorption and activation on different α-Ga2O3 surfaces, namely (001), (100), (110), and (012). The geometries and binding energies of molecular and dissociative adsorption are studied as a function of coverage. The simulations reveal that dissociative water adsorption on all the studied low-index surfaces are thermodynamically favorable. Analysis of surface energies suggests that the most preferentially exposed surface is (012). The contribution of surface relaxation to the respective surface energies is significant. Calculations of electron local density of states indicate that the electron-energy band gaps for the four investigated surfaces appears to be less related to the difference in coordinative unsaturation of the surface atoms, but rather to changes in the ionicity of the surface chemical bonds. The electrochemical computation is used to investigate the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) on α-Ga2O3 surfaces. Our results indicate that the (100) and (110) surfaces, which have low stability, are the most favorable ones for HER and OER, respectively. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Estimated water use and availability in the Pawcatuck Basin, southern Rhode Island and southeastern Connecticut, 1995-99

USGS Publications Warehouse

Wild, Emily C.; Nimiroski, Mark T.

2004-01-01

In 1988, the Pawcatuck Basin (302.4 square miles) in southern Rhode Island (245.3 square miles) and southeastern Connecticut (57.12 square miles) was defined as a sole-source aquifer for 14 towns in southern Rhode Island and 4 towns in southeastern Connecticut. To determine water use and availability, the six subbasins in the Pawcatuck Basin were delineated on the basis of the surface- and ground-water system drainage areas. From 1995 through 1999, five major water suppliers in the basin withdrew an average of 6.768 million gallons per day from the aquifers. The estimated water withdrawals from minor water suppliers during the study period were 0.099 million gallons per day. Self-supplied domestic, industrial, commercial, and agricultural withdrawals from the basin averaged 4.386 million gallons per day. Water use in the basin averaged 7.401 million gallons per day. The average return flow in the basin was 7.855 million gallons per day, which included effluent from permitted facilities and self-disposed water users. The PART program, a computerized hydrographseparation application, was used for five selected index streamgaging stations to determine water availability on the basis of the 75th, 50th, and 25th percentiles of the total base flow, the base flow minus the 7-day, 10-year flow criteria, and the base flow minus the Aquatic Base Flow criteria at the index stations. The differences in the surface- and ground-water system drainage areas in the summer were applied to the water availability calculated at the index stations and subbasins. The base-flow contributions from sand and gravel deposits at the index stations were computed for June, July, August, and September, and applied to the percentage of surficial deposits at each index station. The base-flow contributions were converted to a per unit area at the station for the till, and for the sand and gravel deposits, and applied to the subbasins. The statistics used to estimate the gross yield of base flow, as well as subtracting out the two low-flow criteria, resulted in various wateravailability values at each index station, which were present in the subbasin after applying the per unit area rates from the index station. The results from the Chipuxet and Arcadia streamgaging stations were lowest in September at the 75th and 25th percentiles, and August flows were lowest for the summer at the 50th percentile. For the other three index stations, September flows were the lowest for the summer. Because water withdrawals and use are greater during the summer than other times of the year, water availability in June, July, August, and September was assessed and compared to water withdrawals in the basin and subbasins. The ratios were calculated by using the water-availability flow scenarios at the 75th, 50th, and 25th percentiles for the subbasins, which are based on total water available from base-flow contributions from till deposits and sand and gravel deposits in the subbasins. For the study period, the withdrawals in August were higher than the other summer months. The ratios were close to one in August for the estimated gross yield and 7-day, 10-year flow criterion, and were close to one in September for the estimated Aquatic Base Flow criterion water-availability scenarios in the Pawcatuck Basin. The closer the ratio is to one, the closer the withdrawals are to the estimated water available, and the net water available decreases. To determine the effects of streamflow depletion from continuous water withdrawals, the program STRMDEPL was used to simulate public wells and well fields at a constant pumping rate based on the 1999 summer average for each withdrawal, over a period of 180 days. The streamflow depletion was 86, 95, 93, 96, and 98 percent at 30 days for Kingston wells 1 and 2, Westerly well fields 1 and 2, and well 3, respectively. A long-term hydrologic budget was calculated for the Pawcatuck Basin to identify and assess the basin and subbasin inflow and outflows. The water withdrawals and return flows used in the budget were from 1995 through 1999. For the hydrologic budget, it was assumed that inflow equals outflow, which resulted in 723.1 million gallons per day in the basin. The estimated inflows from precipitation and water return flow were 99 and 1 percent in the basin, respectively. The estimated outflows from evapotranspiration, streamflow, and water withdrawals were 43, 56, and 1 percent, respectively.

Drought assessment in the Dongliao River basin: traditional approaches vs. generalized drought assessment index based on water resources systems

NASA Astrophysics Data System (ADS)

Weng, B. S.; Yan, D. H.; Wang, H.; Liu, J. H.; Yang, Z. Y.; Qin, T. L.; Yin, J.

2015-08-01

Drought is firstly a resource issue, and with its development it evolves into a disaster issue. Drought events usually occur in a determinate but a random manner. Drought has become one of the major factors to affect sustainable socioeconomic development. In this paper, we propose the generalized drought assessment index (GDAI) based on water resources systems for assessing drought events. The GDAI considers water supply and water demand using a distributed hydrological model. We demonstrate the use of the proposed index in the Dongliao River basin in northeastern China. The results simulated by the GDAI are compared to observed drought disaster records in the Dongliao River basin. In addition, the temporal distribution of drought events and the spatial distribution of drought frequency from the GDAI are compared with the traditional approaches in general (i.e., standard precipitation index, Palmer drought severity index and rate of water deficit index). Then, generalized drought times, generalized drought duration, and generalized drought severity were calculated by theory of runs. Application of said runs at various drought levels (i.e., mild drought, moderate drought, severe drought, and extreme drought) during the period 1960-2010 shows that the centers of gravity of them all distribute in the middle reaches of Dongliao River basin, and change with time. The proposed methodology may help water managers in water-stressed regions to quantify the impact of drought, and consequently, to make decisions for coping with drought.

Groundwater level responses to precipitation variability in Mediterranean insular aquifers

NASA Astrophysics Data System (ADS)

Lorenzo-Lacruz, Jorge; Garcia, Celso; Morán-Tejeda, Enrique

2017-09-01

Groundwater is one of the largest and most important sources of fresh water on many regions under Mediterranean climate conditions, which are exposed to large precipitation variability that includes frequent meteorological drought episodes, and present high evapotranspiration rates and water demand during the dry season. The dependence on groundwater increases in those areas with predominant permeable lithologies, contributing to aquifer recharge and the abundance of ephemeral streams. The increasing pressure of tourism on water resources in many Mediterranean coastal areas, and uncertainty related to future precipitation and water availability, make it urgent to understand the spatio-temporal response of groundwater bodies to precipitation variability, if sustainable use of the resource is to be achieved. We present an assessment of the response of aquifers to precipitation variability based on correlations between the Standardized Precipitation Index (SPI) at various time scales and the Standardized Groundwater Index (SGI) across a Mediterranean island. We detected three main responses of aquifers to accumulated precipitation anomalies: (i) at short time scales of the SPI (<6 months); (ii) at medium time scales (6-24 months); and at long time scales (>24 months). The differing responses were mainly explained by differences in lithology and the percentage of highly permeable rock strata in the aquifer recharge areas. We also identified differences in the months and seasons when aquifer storages are more dependent on precipitation; these were related to climate seasonality and the degree of aquifer exploitation or underground water extraction. The recharge of some aquifers, especially in mountainous areas, is related to precipitation variability within a limited spatial extent, whereas for aquifers located in the plains, precipitation variability influence much larger areas; the topography and geological structure of the island explain these differences. Results indicate large spatial variability in the response of aquifers to precipitation in a very small area, highlighting the importance of having high spatial resolution hydro-climatic databases available to enable full understanding of the effects of climate variability on scarce water resources.

Total water storage dynamics derived from tree-ring records and terrestrial gravity observations

NASA Astrophysics Data System (ADS)

Creutzfeldt, Benjamin; Heinrich, Ingo; Merz, Bruno

2015-10-01

For both societal and ecological reasons, it is important to understand past and future subsurface water dynamics but estimating subsurface water storage is notoriously difficult. In this pilot study, we suggest the reconstruction of subsurface water dynamics by a multi-disciplinary approach combining hydrology, dendrochronology and geodesy. In a first step, nine complete years of high-precision gravimeter observations are used to estimate water storage changes in the subsurface at the Geodetic Observatory Wettzell in the Bavarian Forest, Germany. The record is extended to 63 years by calibrating a hydrological model against the 9 years of gravimeter observations. The relationship between tree-ring growth and water storage changes is evaluated as well as that between tree-ring growth and supplementary hydro-meteorological data. Results suggest that tree-ring growth is influenced primarily by subsurface water storage. Other variables related to the overall moisture status (e.g., Standardized Precipitation Index, Palmer Drought Severity Index, streamflow) are also strongly correlated with tree-ring width. While these indices are all indicators of water stored in the landscape, water storage changes of the subsurface estimated by depth-integral measurements give us the unique opportunity to directly reconstruct subsurface water storage dynamics from records of tree-ring width. Such long reconstructions will improve our knowledge of past water storage variations and our ability to predict future developments. Finally, knowing the relationship between subsurface storage dynamics and tree-ring growth improves the understanding of the different signal components contained in tree-ring chronologies.

A MULTI-ASSEMBLAGE INDEX OF STREAM INTEGRITY: WHAT ARE THE FISH, BUGS, AND ALGAE TELLING US?

EPA Science Inventory

Three different taxonomic assemblages have been proposed for use in the biological monitoring and assessment of water quality and stream biological integrity: fishm macroinvertebrates, and periphyton. All three assemblages can be eficiently collected with established methods, ar...

The combination of environmental quality with increasingly rural residence and associations with adverse birth outcomes

EPA Science Inventory

Environmental quality differs across levels of urbanicity, and both urban and rural residence having been previously associated with better health. To explore these relationships, we constructed an environmental quality index (EQI) with data representing five domains (air, water,...

Modeling the ratio of photosynthetically active radiation to broadband global solar radiation using ground and satellite-based data in the tropics

NASA Astrophysics Data System (ADS)

Janjai, S.; Wattan, R.; Sripradit, A.

2015-12-01

Data from four stations in Thailand are used to model the ratio of photosynthetically active radiation (PAR) to broadband global solar radiation. The model expresses the ratio of PAR-to-broadband global solar radiation as a function of cloud index, aerosol optical depth, precipitable water, total ozone column and solar zenith angle. Data from the MTSAT-1R and OMI/AURA satellites are used to estimate the cloud index and total ozone column, respectively at each of the four stations, while aerosol optical depth and precipitable water are retrieved from Aerosol Robotic Network (AERONET) sunphotometer measurements, also available at each station. When tested against hourly measurements, the model exhibits a coefficient of variance (R2) equal to or better than 0.96, and root mean square difference (RMSD) in the range of 7.3-7.9% and mean bias difference (MBD) of -4.5% to 3.5%. The model compares favorably with other existing models.

An improved water budget for the El Yunque National Forest, Puerto Rico, as determined by the Water Supply Stress Index Model

Treesearch

Liangxia Zhang; Ge Sun; Erika Cohen; Steven McNulty; Peter Caldwell; Suzanne Krieger; Jason Christian; Decheng Zhou; Kai Duan; Keren J. Cepero-Pérez

2018-01-01

Quantifying the forest water budget is fundamental to making science-based forest management decisions. This study aimed at developing an improved water budget for the El Yunque National Forest (ENF) in Puerto Rico, one of the wettest forests in the United States. We modified an existing monthly scale water balance model, Water Supply Stress Index (WaSSI), to reflect...

Effect of new organic supplement (Panchgavya) on seed germination and soil quality.

PubMed

Jain, Paras; Sharma, Ravi Chandra; Bhattacharyya, Pradip; Banik, Pabitra

2014-04-01

We studied the suitability of Panchgavya (five products of cow), new organic amendment, application on seed germination, plant growth, and soil health. After characterization, Panchgavya was mixed with water to form different concentration and was tested for seed germination, germination index, and root and shoot growth of different seedlings. Four percent solution of Panchgavya was applied to different plants to test its efficacy. Panchgavya and other two organic amendments were incorporated in soil to test the change of soil chemical and microbiological parameters. Panchgavya contained higher nutrients as compared to farm yard manure (FYM) and vermicompost. Its application on different seeds has positively influenced germination percentage, germination index, root and shoot length, and fresh and dry weight of the seedling. Water-soluble macronutrients including pH and metal were positively and negatively correlated with the growth parameters, respectively. Four percent solution of Panchgavya application on some plants showed superiority in terms of plant height and chlorophyll content. Panchgavya-applied soil had higher values of macro and micronutrients (zinc, copper, and manganese), microbial activity as compared to FYM, and vermicompost applied soils. Application of Panchgavya can be gainfully used as an alternative organic supplement in agriculture.

Assessment of health status of oysters (Crassostreagigas) exposed to environmentally relevant concentrations of Ag and Cu in brackish waters

NASA Astrophysics Data System (ADS)

Rementeria, Ane; Mikolaczyk, Mathilde; Peña, Ainhize; Lanceleur, Laurent; Blanc, Gérard; Soto, Manu; Schäfer, Jörg; Zaldibar, Beñat

2017-12-01

Human activities have altered estuarine environments leading to increased presence of different pollutants including metals. Although the implementation of new environmental policies has caused a considerable decrease in trace metal concentrations in estuaries around the Bay of Biscay, some elements such as copper (Cu) and silver (Ag) are still present in relatively high concentrations. Oysters have been widely used in environmental biomonitoring programs as sentinel organisms. Oysters Crassostrea gigas from an uncontaminated estuary were exposed to sublethal, environmentally relevant concentrations of Cu (2000 ng Cu/L) and Ag (500 ng Ag/L) during 14 days in brackish water (S = 18). A battery of cell and tissue level (exposure) biomarkers at different levels of biological complexity was applied and integrated into the Integrative Biological Response (IBR) index including: metallothionein contents, intralysosomal metal accumulation, digestive gland atrophy and digestive gland tissue integrity. Condition Index (CI) was incorporated into the IBR index as a complementary parameter that reflects the general physiological condition of oysters (organism level). Results indicated an increase in intralysosomal metal accumulation after 7 and 14 days of exposure to Ag together with an increase in the digestive epithelium atrophy and lipofuscin content after 7 days of exposure to Ag. The responses detected with the aid of biomarkers integrated in the IBR index showed higher toxicity in oysters exposed to Ag, inducing the clear onset of detoxification processes which also occurred, to a lower extent, in Cu-exposed oysters.

Physico-chemical characteristics of groundwater in and around Surat City (India).

PubMed

Raval, Viral H; Malik, G M

2010-10-01

Groundwater samples were collected from different locations of Surat city, Gujarat (India). These samples from 32 locations of Surat city were analysed for their physico-chemical characteristics involving pH, colour, odour, hardness, chloride, alkalinity, COD, sulfate, TDS, SS, iron, Cu, boron, chromium, temperature and Langelier Saturation Index. On comparing the results against drinking water quality standards laid by Indian Council of Medical Research (ICMR) and World Health Organization (WHO), it is found that most of the water samples are non-potable. Most of the samples indicated Total Alkalinity, Hardness, Chloride and TDS values much higher than the permissible level stipulated by ICMR and WHO. Even at some places Langelier Saturation Index values found higher too. The high values of these parameters may have health implications and therefore these need attention.

Evaluation of Radar Vegetation Indices for Vegetation Water Content Estimation Using Data from a Ground-Based SMAP Simulator

NASA Technical Reports Server (NTRS)

Srivastava, Prashant K.; O'Neill, Peggy; Cosh, Michael; Lang, Roger; Joseph, Alicia

2015-01-01

Vegetation water content (VWC) is an important component of microwave soil moisture retrieval algorithms. This paper aims to estimate VWC using L band active and passive radar/radiometer datasets obtained from a NASA ground-based Soil Moisture Active Passive (SMAP) simulator known as ComRAD (Combined Radar/Radiometer). Several approaches to derive vegetation information from radar and radiometer data such as HH, HV, VV, Microwave Polarization Difference Index (MPDI), HH/VV ratio, HV/(HH+VV), HV/(HH+HV+VV) and Radar Vegetation Index (RVI) are tested for VWC estimation through a generalized linear model (GLM). The overall analysis indicates that HV radar backscattering could be used for VWC content estimation with highest performance followed by HH, VV, MPDI, RVI, and other ratios.

Experimental datasets on engineering properties of expansive soil treated with common salt.

PubMed

Durotoye, Taiwo O; Akinmusuru, Joseph O; Ogundipe, Kunle E

2018-06-01

Construction of highway pavements or high rise structures over the expansive soils are always problematic due to failures of volume change or swelling characteristic experienced in the water permeability of the soil. The data in this article represented summary of (Durotoye et al., 2016; Durotoye, 2016) [1], [2]. The data explored different percentages of sodium chloride as additive in stabilizing the engineering properties of expansive soil compared with other available stabilizer previously worked on. Experimental procedures carried out on expansive soil include: (Liquid limit, Plastic limit, Plasticity index, Shrinkage limit, Specific gravity Free swell index and Optimum water content) to determine the swelling parameters and (maximum dry density, California bearing ratio and unconfined compressive strength) to determine the strength parameters. The results of the experiment were presented in pie charts.

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement VIII.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials; related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and…

Effect of water stress on total biomass, tuber yield, harvest index and water use efficiency in Jerusalem artichoke

USDA-ARS?s Scientific Manuscript database

The objectives of this study were to determine the effect of drought on tuber yield, total biomass, harvest index, water use efficiency of tuber yield (WUEt) and water use efficiency of biomass (WUEb), and to evaluate the differential responses of Jerusalem artichoke (JA) varieties under drought str...

Drought impacts on vegetation activity in the Mediterranean region: An assessment using remote sensing data and multi-scale drought indicators

NASA Astrophysics Data System (ADS)

Gouveia, C. M.; Trigo, R. M.; Beguería, S.; Vicente-Serrano, S. M.

2017-04-01

The present work analyzes the drought impacts on vegetation over the entire Mediterranean basin, with the purpose of determining the vegetation communities, regions and seasons at which vegetation is driven by drought. Our approach is based on the use of remote sensing data and a multi-scalar drought index. Correlation maps between fields of monthly Normalized Difference Vegetation Index (NDVI) and the Standardized Precipitation-Evapotranspiration Index (SPEI) at different time scales (1-24 months) were computed for representative months of winter (Feb), spring (May), summer (Aug) and fall (Nov). Results for the period from 1982 to 2006 show large areas highly controlled by drought, although presenting high spatial and seasonal differences, with a maximum influence in August and a minimum in February. The highest correlation values are observed in February for 3 months' time scale and in May for 6 and 12 months. The higher control of drought on vegetation in February and May is obtained mainly over the drier vegetation communities (Mediterranean Dry and Desertic) at shorter time scales (3 to 9 months). Additionally, in February the impact of drought on vegetation is lower for Temperate Oceanic and Continental vegetation types and takes place at longer time scales (18-24). The dependence of drought time-scale response with water balance, as obtained through a simple difference between precipitation and reference evapotranspiration, varies with vegetation communities. During February and November low water balance values correspond to shorter time scales over dry vegetation communities, whereas high water balance values implies longer time scales over Temperate Oceanic and Continental areas. The strong control of drought on vegetation observed for Mediterranean Dry and Desertic vegetation types located over areas with high negative values of water balance emphasizes the need for an early warning drought system covering the entire Mediterranean basin. We are confident that these results will provide a useful tool for drought management plans and play a relevant role in mitigating the impact of drought episodes.

Managing the financial risk of low water levels in Great Lakes with index-based contracts

NASA Astrophysics Data System (ADS)

Meyer, E.; Characklis, G. W.; Brown, C. M.; Moody, P.

2014-12-01

Low water levels in the Great Lakes have recently had significant financial impacts on the region's commercial shipping, responsible for transporting millions of dollars' worth of bulk goods each year. Low lake levels can significantly affect shipping firms, as cargo capacity is a function of draft, or the distance between water level and the ship's bottom. Draft increases with weight, and lower lake levels force ships to reduce cargo to prevent running aground in shallow harbors, directly impacting the finances of shipping companies. Risk transfer instruments may provide adaptable, yet unexplored, alternatives for managing these financial risks, at significantly less expense than more traditional solutions (e.g., dredging). Index-based financial instruments can be particularly attractive as contract payouts are directly linked to well-defined transparent metrics (e.g., lake levels), eliminating the need for subjective adjustors, as well as concerns over moral hazard. In developing such instruments, a major challenge is identifying an index that is well correlated with financial losses, and thus a contract that reliably pays out when losses are experienced (low basis risk). In this work, a relationship between lake levels and shipping revenues is developed, and actuarial analyses of the frequency and magnitude of revenue losses is completed using this relationship and synthetic water level data. This analysis is used to develop several types of index-based contracts. A standardized suite of binary contracts is developed, with each indexed to lake levels and priced according to predefined thresholds. These are combined to form portfolios with different objectives (e.g. options, collars), with optimal portfolio structure and length of coverage determined by limiting basis risk and contract cost, using simulations over the historic dataset. Results suggest that portfolios of these binary contracts can substantially reduce the risk of financial losses during periods of low lake level at a cost of only 1-3% of total revenues.

Statistical, time series, and fractal analysis of full stretch of river Yamuna (India) for water quality management.

PubMed

Parmar, Kulwinder Singh; Bhardwaj, Rashmi

2015-01-01

River water is a major resource of drinking water on earth. Management of river water is highly needed for surviving. Yamuna is the main river of India, and monthly variation of water quality of river Yamuna, using statistical methods have been compared at different sites for each water parameters. Regression, correlation coefficient, autoregressive integrated moving average (ARIMA), box-Jenkins, residual autocorrelation function (ACF), residual partial autocorrelation function (PACF), lag, fractal, Hurst exponent, and predictability index have been estimated to analyze trend and prediction of water quality. Predictive model is useful at 95% confidence limits and all water parameters reveal platykurtic curve. Brownian motion (true random walk) behavior exists at different sites for BOD, AMM, and total Kjeldahl nitrogen (TKN). Quality of Yamuna River water at Hathnikund is good, declines at Nizamuddin, Mazawali, Agra D/S, and regains good quality again at Juhikha. For all sites, almost all parameters except potential of hydrogen (pH), water temperature (WT) crosses the prescribed limits of World Health Organization (WHO)/United States Environmental Protection Agency (EPA).

Peculiarities of the Bound Water and Water Ice Seasonal Variations in the Martian Surface Layer of the Regolith.

NASA Astrophysics Data System (ADS)

Kuzmin, R. O.; Zabalueva, E. V.; Evdokimova, N. A.; Christensen, P. H.; Mitrofanov, I. G.; Litvak, M. L.

2008-09-01

Introduction: The processes of the hydration/ dehydration of salt minerals within the Martian soil and the condensation/sublimation of water ice (and frost) in the surficial soil layer and on the polar cap surface play great significance in the modern water cycle on Mars and directly affect the redistribution of the water phases and forms in the system "atmosphere/regolith/polar caps" [1, 2, 3, 4, 5]. The processes are reversible in time and their intensity is strongly dependent on such time-variable climatic parameters as atmospheric and surface temperature, atmospheric water vapour content and specific features of atmospheric seasonal circulation [6, 7, 8, 9, 10]. In the work we report the study results of the seasonal variations of the chemically bound water (BW) spectral signature (based on the TES and OMEGA data), estimation and mapping of the winterand spring-time water ice increase within the Martian surface soil (based on the TES and HEND data). Analysis and results: Regional and global mapping of the BW spectral index distribution as function of the seasons was conducted by using of the 6.1 μm emission pick from the TES dataset and the 1.91 μm absorption band from reflectance spectra of the OMEGA data. The study of the seasonal redistribution of the water ice (and frost) within the thin surficial soil layer was conducted based on the TES thermal inertia (TI) data and the HEND neutrons flux mapping data. Bound water mapping: The mapping of the TES 6.1 μm BW index distributions was conducted at the time steps from 30° to 60° of Ls [11]. The mapping results show remarkable changes of the BW index values from one season to other one at notable latitudinal dependence of the index (Fig.1). At that, the higher BW index values are disposed mostly within the peripheral zone near the edge of the perennial and seasonal polar caps (cooler, wetter areas), while the lower BW index values are observed at low latitudes (warmer, drier areas). Between the Nspring (Ls=0°-90°) and winter (Ls=270°-360°) the zone with maximum values of BW index is shifting gradually from high latitudes to middle latitudes (20°- 30°N), being mostly disappearing in the period of Ls=150°-210°. Mapping results demonstrates that intensity of the TES 6.1 μm BW index correlates well with albedo, being higher in the brighter dusty areas and lower in the darker areas on Mars. Nevertheless, the seasonal variations of the BW index are characteristic for both bright and dark surfaces. The distinct hemispherical asymmetry of the BW index distribution is observed during the N-summer, while during the S-summer the asymmetry is much less visible. The observing time range from hydrated to dehydrated states of surface materials corresponds to the Ls range from 15° to 30° (from ~1 to 2 months). The time scale may to be conforming to the rate of the hydration/dehydration process for the Mg- and Fesulfates, composing part of the Martian soil [12, 13]. The BW index based on 1.91μm band has been mapped for spring and summer by using the OMEGA data of the first and second Martian year observations. As well in the case of the TES BW index, the mapping results of the 1.91 μm BW index also shown remarkable difference in the bound water distribution between spring and summer seasons (Fig.2). Seasonal water ice increase in the surface regolith: To define the order of the winter-time increase of the water ice within the Martian surface layer corresponding to the daily thermal skin depth (3- 10 cm in thickness) we compared the difference between the TI values mapped separately for the Nsummer- (Ls=120°-150°) and the N-winter (Ls=300°- 310°) in the latitude range ±50° out of the seasonal CO2 ice cover. We consider the summer-time and the winter-time TI values as characteristic of the dry and icy soils correspondingly. To estimate the possible water ice amount increase in the soil during winter we definition based on relationship between TI dry soil_ and TI icy soil (computed for different soil's ice content from 0% to 10%)._Following to the estimations, the zonally averaged (in 5°-latitude belts) winter-time TI values are consistent with a soil's ice content from 2-8 vol. % in the latitude ranges 30°-50°N and 40°-50°S to < 1 vol. % (and up to dry soil) at a lower latitudes 0-30° S/N. The water ice volume part was estimated for all coincided summer and winter TES TI surface footprints by solving of the quadratic equation, received at inclusion of the thermal parameters for two-component mixture (soil+ice) into formula of thermal inertia [15]. The estimated winter-time amount of water ice in the Martian soil was globally mapped and the received result is shown on Figure 3. The described method we also applied for estimation and mapping of the water ice within surficial soil in the peripheral zone of the retreating seasonal CO2 ice cap, where the polar water ice annulus (~5° circular belt) has been observed recently [16,17]. In our report we will discuss the character of the soil's water ice amount dynamics in the belt as function of the Ls and latitude. Example of the water ice amount mapping within the surficial soil in the circular belt for Ls=0-40° is shown on figure 4. As one can see from the map, the ice amount in the soil layer (with thickness 3-10cm) within the belt is varies from 3 to 11 vol. %. The seasonal variations of the water amount within thicker surface layer (up to depth 20-30 cm), we had analyzed [18] based on the HEND fast neutrons flux data (with energy range 2.5-10 Mev (FN2)) collected during two Martian years [19]. We found that distribution of the water equivalent on Mars shows notable annual differences (Fig.5). At that, the picture of the winter-time (in both hemispheres) water equivalent distribution has visible similarity with trend of the winter-time distribution of the water ice (frost) derived from the TES TI data. Conclusion: The received results of the joint analysis of the TES, HEND and OMEGA data demonstrates existence of the strong seasonal effect of the bound water and water ice amount variations in the surficial soil layer with thickness from a hundreds microns up to 20-30 cm. Appearance of the water ice in the surficial soil layer around of receding CO2 ice cap serves as direct conformation of the seasonal permafrost layer formation on Mars. Our results shown that mapped amount of the soil's water ice (involved in the seasonal redistribution) exceed notably the content of the atmospheric water. This means that the role of the regolith in the modern water cycle on Mars may to be much significant than it was suggested before. References: [1] Fanale F.P. et al., (1986), Icarus, 68, 1- 18 ; [2] Zent A.P. et al, (1995), JGR, 100, 5341-5349 ; [3] Zolotov M. Yu. (1989), LPSC XX, 1257-1258 ; [4] Mohlmann D.T.F. (2004), Icarus, 168, 318-323 ; [5] Tokano T. (2003), Icarus, 164, 50-78 ; [6] Mellon M.T. and Jakosky B.M. (1995), JGR, 100, 11781-11799 ; [7] Bottger H.M. et al., (2004), JGL, 31,L22702; [8] Smith M.D. (2004), Icarus, 167, 148-165 ; [9] Bish D.L. et al., (2003), Icarus, 164, 96- 103 ; [10] Kuzmin R.O. et al., (2007), Solar System Reseach, 41, 99-102 ; [11] Kuzmin R.O. et al., (2006), LPSC XXXVII, #1846 ; [12] Chipera S.J., Vaniman D.T. (2007), Geoch. et Cosmoch. Acta, 71, 241-250 ; [13] Chou I-M, R.R. Seal II (2007), JGR, 112, E11004, doi : 10.1029/2007JE002898 ; [14] Kuzmin R.O. et al., (2007) 7th Mars Conf., #3022; [15] Kuzmin R.O. et al., (2007), Europian Mars Science and Exploration Conference : Mars Express & ExoMars, # 1120023 ;[16] Titus, T.N. (2005), Lunar. Planet. Sci.XXXVI, Abstract #1993; [17] Wagstaff, K.L., T.N. Titus, A.B. Ivanov, R. Castano, J.L.Bandfield. (2008), Planetary and Space Science, 56, 256-265;[18] Kuzmin R.O. et al., (2007), Brown-Vernadsky Microsymp. 46th (www.planetology.ru/micro.php.); [19] Litvak M.L. et al., (2007), Solar System Reseach, 41,5, 385-397. used the nomogram [14], created for ice content

Peculiarities of the Bound Water and Water Ice Seasonal Variations in the Martian Surface Layer of the Regolith.

NASA Astrophysics Data System (ADS)

Kuzmin, R. O.; Zabalueva, E. V.; Evdokimova, N. A.; Christensen, P. H.; Mitrofanov, I. G.; Litvak, M. L.

2008-09-01

Introduction: The processes of the hydration/ dehydration of salt minerals within the Martian soil and the condensation/sublimation of water ice (and frost) in the surficial soil layer and on the polar cap surface play great significance in the modern water cycle on Mars and directly affect the redistribution of the water phases and forms in the system "atmosphere/regolith/polar caps" [1, 2, 3, 4, 5]. The processes are reversible in time and their intensity is strongly dependent on such time-variable climatic parameters as atmospheric and surface temperature, atmospheric water vapour content and specific features of atmospheric seasonal circulation [6, 7, 8, 9, 10]. In the work we report the study results of the seasonal variations of the chemically bound water (BW) spectral signature (based on the TES and OMEGA data), estimation and mapping of the winterand spring-time water ice increase within the Martian surface soil (based on the TES and HEND data). Analysis and results: Regional and global mapping of the BW spectral index distribution as function of the seasons was conducted by using of the 6.1 μm emission pick from the TES dataset and the 1.91 μm absorption band from reflectance spectra of the OMEGA data. The study of the seasonal redistribution of the water ice (and frost) within the thin surficial soil layer was conducted based on the TES thermal inertia (TI) data and the HEND neutrons flux mapping data. Bound water mapping: The mapping of the TES 6.1 μm BW index distributions was conducted at the time steps from 30° to 60° of Ls [11]. The mapping results show remarkable changes of the BW index values from one season to other one at notable latitudinal dependence of the index (Fig.1). At that, the higher BW index values are disposed mostly within the peripheral zone near the edge of the perennial and seasonal polar caps (cooler, wetter areas), while the lower BW index values are observed at low latitudes (warmer, drier areas). Between the Nspring (Ls=0°-90°) and winter (Ls=270°-360°) the zone with maximum values of BW index is shifting gradually from high latitudes to middle latitudes (20°- 30°N), being mostly disappearing in the period of Ls=150°-210°. Mapping results demonstrates that intensity of the TES 6.1 μm BW index correlates well with albedo, being higher in the brighter dusty areas and lower in the darker areas on Mars. Nevertheless, the seasonal variations of the BW index are characteristic for both bright and dark surfaces. The distinct hemispherical asymmetry of the BW index distribution is observed during the N-summer, while during the S-summer the asymmetry is much less visible. The observing time range from hydrated to dehydrated states of surface materials corresponds to the Ls range from 15° to 30° (from ~1 to 2 months). The time scale may to be conforming to the rate of the hydration/dehydration process for the Mg- and Fesulfates, composing part of the Martian soil [12, 13]. The BW index based on 1.91μm band has been mapped for spring and summer by using the OMEGA data of the first and second Martian year observations. As well in the case of the TES BW index, the mapping results of the 1.91 μm BW index also shown remarkable difference in the bound water distribution between spring and summer seasons (Fig.2). Seasonal water ice increase in the surface regolith: To define the order of the winter-time increase of the water ice within the Martian surface layer corresponding to the daily thermal skin depth (3- 10 cm in thickness) we compared the difference between the TI values mapped separately for the Nsummer- (Ls=120°-150°) and the N-winter (Ls=300°- 310°) in the latitude range ±50° out of the seasonal CO2 ice cover. We consider the summer-time and the winter-time TI values as characteristic of the dry and icy soils correspondingly. To estimate the possible water ice amount increase in the soil during winter we used the nomogram [14], created for ice content definition based on relationship between TI dry soil_ and TI icy soil (computed for different soil's ice content from 0% to 10%)._Following to the estimations, the zonally averaged (in 5°-latitude belts) winter-time TI values are consistent with a soil's ice content from 2-8 vol. % in the latitude ranges 30°-50°N and 40°-50°S to < 1 vol. % (and up to dry soil) at a lower latitudes 0-30° S/N. The water ice volume part was estimated for all coincided summer and winter TES TI surface footprints by solving of the quadratic equation, received at inclusion of the thermal parameters for two-component mixture (soil+ice) into formula of thermal inertia [15]. The estimated winter-time amount of water ice in the Martian soil was globally mapped and the received result is shown on Figure 3. The described method we also applied for estimation and mapping of the water ice within surficial soil in the peripheral zone of the retreating seasonal CO2 ice cap, where the polar water ice annulus (~5° circular belt) has been observed recently [16,17]. In our report we will discuss the character of the soil's water ice amount dynamics in the belt as function of the Ls and latitude. Example of the water ice amount mapping within the surficial soil in the circular belt for Ls=0-40° is shown on figure 4. As one can see from the map, the ice amount in the soil layer (with thickness 3-10cm) within the belt is varies from 3 to 11 vol. %. The seasonal variations of the water amount within thicker surface layer (up to depth 20-30 cm), we had analyzed [18] based on the HEND fast neutrons flux data (with energy range 2.5-10 Mev (FN2)) collected during two Martian years [19]. We found that distribution of the water equivalent on Mars shows notable annual differences (Fig.5). At that, the picture of the winter-time (in both hemispheres) water equivalent distribution has visible similarity with trend of the winter-time distribution of the water ice (frost) derived from the TES TI data. Conclusion: The received results of the joint analysis of the TES, HEND and OMEGA data demonstrates existence of the strong seasonal effect of the bound water and water ice amount variations in the surficial soil layer with thickness from a hundreds microns up to 20-30 cm. Appearance of the water ice in the surficial soil layer around of receding CO2 ice cap serves as direct conformation of the seasonal permafrost layer formation on Mars. Our results shown that mapped amount of the soil's water ice (involved in the seasonal redistribution) exceed notably the content of the atmospheric water. This means that the role of the regolith in the modern water cycle on Mars may to be much significant than it was suggested before. References: [1] Fanale F.P. et al., (1986), Icarus, 68, 1- 18 ; [2] Zent A.P. et al, (1995), JGR, 100, 5341-5349 ; [3] Zolotov M. Yu. (1989), LPSC XX, 1257-1258 ; [4] Mohlmann D.T.F. (2004), Icarus, 168, 318-323 ; [5] Tokano T. (2003), Icarus, 164, 50-78 ; [6] Mellon M.T. and Jakosky B.M. (1995), JGR, 100, 11781-11799 ; [7] Bottger H.M. et al., (2004), JGL, 31,L22702; [8] Smith M.D. (2004), Icarus, 167, 148-165 ; [9] Bish D.L. et al., (2003), Icarus, 164, 96- 103 ; [10] Kuzmin R.O. et al., (2007), Solar System Reseach, 41, 99-102 ; [11] Kuzmin R.O. et al., (2006), LPSC XXXVII, #1846 ; [12] Chipera S.J., Vaniman D.T. (2007), Geoch. et Cosmoch. Acta, 71, 241-250 ; [13] Chou I-M, R.R. Seal II (2007), JGR, 112, E11004, doi : 10.1029/2007JE002898 ; [14] Kuzmin R.O. et al., (2007) 7th Mars Conf., #3022; [15] Kuzmin R.O. et al., (2007), Europian Mars Science and Exploration Conference : Mars Express & ExoMars, # 1120023 ;[16] Titus, T.N. (2005), Lunar. Planet. Sci.XXXVI, Abstract #1993; [17] Wagstaff, K.L., T.N. Titus, A.B. Ivanov, R. Castano, J.L.Bandfield. (2008), Planetary and Space Science, 56, 256-265;[18] Kuzmin R.O. et al., (2007), Brown-Vernadsky Microsymp. 46th (www.planetology.ru/micro.php.); [19] Litvak M.L. et al., (2007), Solar System Reseach, 41,5, 385-397.

Probabilistic Analysis of Earthquake-Led Water Contamination: A Case of Sichuan, China

NASA Astrophysics Data System (ADS)

Yang, Yan; Li, Lin; Benjamin Zhan, F.; Zhuang, Yanhua

2016-06-01

The objective of this paper is to evaluate seismic-led point source and non-point source water pollution, under the seismic hazard of 10 % probability of exceedance in 50 years, and with the minimum value of the water quality standard in Sichuan, China. The soil conservation service curve number method of calculating the runoff depth in the single rainfall event combined with the seismic damage index were applied to estimate the potential degree of non-point source water pollution. To estimate the potential impact of point source water pollution, a comprehensive water pollution evaluation framework is constructed using a combination of Water Quality Index and Seismic Damage Index methods. The four key findings of this paper are: (1) The water catchment that has the highest factory concentration does not have the highest risk of non-point source water contamination induced by the outbreak of potential earthquake. (2) The water catchment that has the highest numbers of cumulative water pollutants types are typically located in the south western parts of Sichuan where the main river basins in the regions flow through. (3) The most common pollutants in sample factories studied is COD and NH3-N which are found in all catchments. The least common pollutant is pathogen—found present in W1 catchment which has the best rating in the water quality index. (4) Using water quality index as a standardization parameter, parallel comparisons is made among the 16 water catchments. Only catchment W1 reaches level II water quality status which has the rating of moderately polluted in events of earthquake induced water contamination. All other areas suffer from severe water contamination with multiple pollution sources. The results from the data model are significant to urban planning commissions and businesses to strategically choose their factory locations in order to minimize potential hazardous impact during the outbreak of earthquake.

A multiple index integrating different levels of organization.

PubMed

Cortes, Rui; Hughes, Samantha; Coimbra, Ana; Monteiro, Sandra; Pereira, Vítor; Lopes, Marisa; Pereira, Sandra; Pinto, Ana; Sampaio, Ana; Santos, Cátia; Carrola, João; de Jesus, Joaquim; Varandas, Simone

2016-10-01

Many methods in freshwater biomonitoring tend to be restricted to a few levels of biological organization, limiting the potential spectrum of measurable of cause-effect responses to different anthropogenic impacts. We combined distinct organisational levels, covering biological biomarkers (histopathological and biochemical reactions in liver and fish gills), community based bioindicators (fish guilds, invertebrate metrics/traits and chironomid pupal exuviae) and ecosystem functional indicators (decomposition rates) to assess ecological status at designated Water Framework Directive monitoring sites, covering a gradient of human impact across several rivers in northern Portugal. We used Random Forest to rank the variables that contributed more significantly to successfully predict the different classes of ecological status and also to provide specific cut levels to discriminate each WFD class based on reference condition. A total of 59 Biological Quality Elements and functional indicators were determined using this procedure and subsequently applied to develop the integrated Multiple Ecological Level Index (MELI Index), a potentially powerful bioassessment tool. Copyright © 2016 Elsevier Inc. All rights reserved.

Seasonal variation in imposex intensity of Thais clavigera

NASA Astrophysics Data System (ADS)

Li, Zhengyan

2005-06-01

Imposex, specifically caused by TBT pollution, refers to the superimposition of male sexual characteristics in gastropod females. Seasonal variation of imposex intensity in Thais clavigera from both slightly and severely contaminated sites in Hong Kong waters was studied from 1988 to 1999. The male penis length showed significant difference between both sites and seasons. It was shortest during late autumn and early winter (October to December) and longest during spring and early summer (February to June). Female penis length also showed significant difference between sites. It did not change seasonally, however. The RPS (Relative Penis Size) index was the highest during autumn and early winter, and the lowest during spring and early summer. The VDS (Vas Deferens Sequence) index remained stable throughout the sampling period. This study showed that VDS index is a better indicator when we compare relative intensity of imposex. The comparison can only be meaningful provided the samples from different locations are taken during the same season.

Assessing the productivity change of water companies in England and Wales: A dynamic metafrontier approach.

PubMed

Molinos-Senante, María; Maziotis, Alexandros; Sala-Garrido, Ramon

2017-07-15

The assessment of productivity change and its drivers across water companies and over time is a powerful tool for both regulators and companies when setting water tariffs. Water and sewerage companies (WaSCs) and water only companies (WoCs) provide different services. Hence, their productivity change cannot directly be evaluated jointly. In this paper and for the first time, we provide a pioneering approach to assess and compare the dynamics of productivity change of WaSCs and WoCs. To achieve this, both the traditional Malmquist productivity index and the metafrontier Malmquist productivity index and its components are computed to assess the productivity change for a sample of English and Welsh water companies over the period 2001-2014. The findings from both indices indicate that productivity for both WaSCs and WoCs did not improve during this period, mainly due to the negative shift in the production frontier which offset the positive effect of efficiency change. It is also reported that the performance of the WoCs over time was slightly better than that of the WaSCs. Finally, our study provides some insights into the relationship between productivity change and the regulatory cycle. This information is essential to improve the regulation of water and sewerage services, contributing to the long-term sustainability of the urban water cycle. Copyright © 2017 Elsevier Ltd. All rights reserved.

Estimating Groundwater Development area in Jianan Plain using Standardized Groundwater Index

NASA Astrophysics Data System (ADS)

Yu, Chang Hsiang; Haw, Lee Cheng

2017-04-01

Taiwan has been facing severe water crises in recent years owing to the effects of extreme weather conditions. Changes in precipitation patterns have also made the drought phenomenon increasingly prominent, which has indirectly affected groundwater recharge. Hence, in the present study, long-term monitoring data were collected from the study area of the Jianan plain. The standardized groundwater index (SGI) and was then used to analyse the region's drought characteristics. To analyse the groundwater level by using SGI, making SGI180 groundwater level be the medium water crises, and SGI360 groundwater level be the extreme water crises. Through the different water crises signal in SGI180 and SGI360, we divide groundwater in Jianan plain into two sections. Thereby the water crises indicators establishing groundwater level standard line in Jianan Plain, then using the groundwater level standard line to find the study area where could be groundwater development area in Jianan plain. Taking into account relatively more water scarcity in dry season, so the study screen out another emergency backup groundwater development area, but the long-term groundwater development area is still as a priority development area. After finding suitable locations, groundwater modeling systems(GMS) software is used to simulate our sites to evaluate development volume. Finally, the result of study will help the government to grasp the water shortage situation immediately and solve the problem of water resources deployment.

Effects of Advice to Drink 8 Cups of Water per Day in Adolescents With Overweight or Obesity: A Randomized Clinical Trial.

PubMed

Wong, Julia M W; Ebbeling, Cara B; Robinson, Lisa; Feldman, Henry A; Ludwig, David S

2017-05-01

Health care professionals commonly recommend increased water consumption, typically to 8 cups per day, as part of a weight-reducing diet. However, this recommendation is based on limited evidence and virtually no experimental data from the pediatric population. To compare 2 standardized weight-loss diets among adolescents with overweight or obesity, either with or without additional advice and behavioral support to increase habitual water intake to 8 cups per day. A randomized clinical, parallel-group trial was conducted between February 2, 2011, and June 26, 2014, at Boston Children's Hospital, Boston, Massachusetts, among 38 adolescents with overweight or obesity who reported drinking 4 cups or less of water per day. All participants in both groups received similar weight-reducing interventions, differentiated by advice about water intake (the water group received advice to increase water intake to 8 cups per day; the control group did not receive such advice) but controlled for other dietary recommendations and treatment intensity. The interventions included dietary counseling, daily text messages, and a cookbook with health guides. To support adherence to 8 cups of water per day, the water group received well-defined messages about water through counseling and daily text messages, a water bottle, and a water pitcher with filters. The primary outcome was 6-month change in body mass index z score. Data analyses followed the intention-to-treat principle. All 38 participants (27 girls and 11 boys; mean [SD] age, 14.9 [1.7] years) completed the study. Both groups reported drinking approximately 2 cups of water per day at baseline. Self-reported change in water intake at 6 months was greater in the water group (difference from baseline, 2.8 cups per day [95% CI, 1.8 to 3.8]; P < .001) compared with that in the control group (difference from baseline, 1.2 cups per day [95% CI, 0.2 to 2.2]; P = .02) (difference between groups, 1.6 cups per day [95% CI, 0.2 to 3.0 cups per day]; P = .03). The 6-month change in body mass index z score did not differ between the water group (difference from baseline, -0.1 [95% CI, -0.2 to -0.0]; P = .005) and the control group (difference from baseline, -0.1 [95% CI, -0.2 to -0.0]; P = .008) (difference between groups, -0.0 [95% CI, -0.1 to 0.1]; P = .88). Advice and behavioral supports to consume 8 cups of water per day in the context of a weight-reducing diet did not affect body weight among adolescents with overweight or obesity. Despite intensive behavior supports, few adolescents achieved the target of 8 cups of water per day. Environmental interventions to reduce barriers to water consumption at school may be necessary in future research of the feasibility and effectiveness to achieve the target of an intake of 8 cups of water per day in adolescents. clinicaltrials.gov Identifier: NCT01044134.

The Body Mass Index of San Francisco Cold-water Swimmers: Comparisons to U.S. National and Local Populations, and Pool Swimmers

PubMed Central

CROW, BRENDAN T.; MATTHAY, ELLICOTT C.; SCHATZ, STEPHEN P.; DEBELISO, MARK D.; NUCKTON, THOMAS J.

2017-01-01

To determine if cold-water swimmers have substantial differences in BMI, which might have a protective effect against heat loss during swims in cold water without wetsuits, and to determine if obesity is more or less prevalent in cold-water swimmers, we compared the body mass index (BMI) values of 103 recreational open-water swimmers (mean age 54.3 ±10.8 years) to data from various population groups. Swimmers swam consistently throughout the winter months, in the San Francisco Bay (water temperature range: 9.6° C [49.3 ° F] to 12.6° C [54.7 ° F]), without wetsuits. After matching for age and sex, the average BMI of cold-water swimmers (25.9 kg/m2) was lower than the corresponding predicted U.S. average BMI (29.2 kg/m2; p<.001), the predicted California state average BMI (28.0 kg/m2; p<.001), and the predicted San Francisco city average BMI (26.6 kg/m2; p=.047). The average BMI value for cold-water swimmers (25.9 kg/m2) was not significantly different from values of North American masters pool swimmers (25.1 kg/m2; p=.15) or international masters pool swimmers (25.3 kg/m2; p=.16). 10.7% of cold-water swimmers were classified as obese (BMI > 30 kg/m2) vs. 35.7%, 25.8%, and 11.8% of the U.S., California, and San Francisco populations, respectively. The lower or similar BMI values of our swimmers suggest that successful recreational swimming in cold water is influenced by factors other than body habitus, such as acclimatization, heat production while swimming, and most importantly, limiting immersion time. The relatively low prevalence of obesity in our swimmers suggests that cold-water swimming could contribute to a healthy lifestyle. PMID:29399251

Correlation of water with carbon/energy footprints for effective agricultural and livestock products classification

NASA Astrophysics Data System (ADS)

Borsato, Eros; Marinello, Francesco; Tarolli, Paolo

2017-04-01

World population is increasing and human diet is becoming of considerable concern for human welfare. Natural resources are overexploited and governments need policies for a good management of the environment. Sustainable agriculture can provide some solutions, as it minimizes inputs, wastes or pollution. The aim of the present study is to provide a combined analysis of different footprints approaches in order to allow comparison of different agricultural and livestock products in terms of efficiency of resource exploitation. Time is the real important variable that influences the footprint. Water use efficiency, greenhouse gas emissions and energy indexes are included in this study. The study takes advantage of indexes collected from a wide bibliography focused on different fresh agricultural products: the target is the definition of a time table of footprints for agricultural products. Starting from a top-down prospective, an analysis of the environmental footprint for different products is an approach to understand which products can be more sustainable for human diet. This study distinguishes different clusters in different sub-cluster of vegetable products and animal products. The classification is based on a comparison of water consumption in relation to yield, greenhouse gas emissions equivalent and energy for a given product quantity. Additionally time is considered, which affects sustainability, in terms of inputs caught for a period. The footprint is spread out in time, thus changing its relevance with respect to the exploitation of a resource. Ultimately, this works wants to propose a new original basis for sustainability metrics, allowing an effective quantitative comparison of food products for a more conscious human diet.

A GIS-derived integrated moisture index

Treesearch

Louis R. Iverson; Anantha M. Prasad

2003-01-01

A geographic information system (GIS) approach was used in conjunction with forest-plot data to develop an integrated moisture index (IMI) that is being used to stratify and help explain landscape-level phenomena in the four study areas. Several landscape features (a slope-aspect shading index, cumulative flow of water downslope, curvature of the landscape, and water-...

Influence of polluted SY River on child growth and sex hormones.

PubMed

Tang, Chun Yu; Li, An Qi; Guan, Yong Bo; Li, Yan; Cheng, Xue Min; Li, Ping; Li, Shi Qun; Luo, Yi Xin; Huang, Qi; Chen, Hong Yang; Cui, Liu Xin

2012-06-01

To investigate the influence of the polluted SY River on children's growth and sex hormones, and provide scientific data for assessment of the polluted status of the SY River. The study areas were selected randomly from the SY River Basin. Lead (Pb), mercury (Hg), arsenic (As), phthalates (DEP, DBP, DMP, DEHP), and bisphenol A (BPA) were measured both in the river water and in the drinking water. School children were selected by cluster sampling (n=154). Physical development indexes (height, weight, bust-circumference, and skinfold thickness) and sex hormones [testosterone (T) and estradiol (E2)] were measured for all the children. The contents of Pb and Hg exceeded Class V standards of surface water quality in each section of the river and other indicators exceeded Class III. Compared to the control area, the concentrations of Pb, Hg, As, BPA, DEP, and DBP in the drinking water were significantly higher than in the polluted area (P<0.05). Children from the control area had significantly lower E2 and T than children from the polluted area (P<0.05). Among anthropometric results, only skinfold thickness had statistically significant difference between the two groups (P<0.05), while the other indexes showed no significant differences between the two groups (P>0.05). The drinking water has been polluted by the SY River and affected serum sex hormone levels of children living in the polluted area. Copyright © 2012 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.

Evaluation of surface water quality indices and ecological risk assessment for heavy metals in scrap yard neighbourhood.

PubMed

Ojekunle, Olusheyi Z; Ojekunle, Olurotimi V; Adeyemi, Azeem A; Taiwo, Abayomi G; Sangowusi, Opeyemi R; Taiwo, Adewale M; Adekitan, Adetoun A

2016-01-01

Pollution of surface water with heavy metals from industrial activities especially those from scrap yard has caused a major threat to human life exposing man to series of hazard, diseases, disability and consequently death. This study focuses on water quality indices of Owode-Onirin and Lafenwa scrap yard with respect to its physicochemical parameters and heavy metal concentrations by evaluating Heavy Metal Pollution Index (HPI), Metal Index (MI) and Potential Ecological Risk Index (PERI). Fifteen water samples were selected randomly from two locations by purposive sampling methods. Five heavy metals which includes Nickel (Ni), Zinc (Zn), Copper (Cu), Cadmium (Cd), Lead (Pb) were analyzed using Atomic Absorption Spectroscopy and standard analytical procedure were follow to ensure accuracy. One way analysis of variance was carried out to analyse the data. The concentrations of the heavy metals were significantly different between sampling locations. However, the mean concentrations of Cd (0.0121 mg/L) were found to be above the highest permissible value of Standard Organization of Nigeria standards for drinking water (SON 2007) and WHO (Guidelines for drinking water quality: incorporating 1st and 2nd Addlenda. World Health Organization, Geneva, 2004) for drinking water. Although Pb was present in two out of the fifteen water samples with a mean value of (0.0324 mg/L) which was also above the highest permissible value. The mean concentrations of Zn (0.2149 mg/L) and Cu (0.0341 mg/L) are found to be below the highest permissible value of the mentioned guideline while no trace of Ni was found in the water samples across the two sampling locations. The mean HPI 518.55 is far above the critical value of 100, indicates that selected water samples are critically polluted with heavy metals. MI revealed low quality water with mean value 4.83, suggests that the selected water is seriously affected with the present of heavy metal. The Hakanson PERI indicated that of the five heavy metals, the risk coefficient of Zn, Pb, Cu, and Ni had light levels of contamination while the level of Cd contamination posed the most serious potential ecological risk, with an index value between 14.1 and 234. The study concluded that order of magnitude to this five heavy metals contamination is Cd > Pb > Zn > Cu > Ni.

Using a Budyko Derived Index to Evaluate the Internal Hydrological Variability of Catchments in Complex Terrain

NASA Astrophysics Data System (ADS)

Dominguez, M.

2017-12-01

Headwater catchments in complex terrain typically exhibit significant variations in microclimatic conditions across slopes. This microclimatic variability in turn, modifies land surface properties presumably altering the hydrologic dynamics of these catchments. The extent to which differences in microclimate and land cover dictate the partition of water and energy fluxes within a catchment is still poorly understood. In this study, we attempt to do an assessment of the effects of aspect, elevation and latitude (which are the principal factors that define microclimate conditions) on the hydrologic behavior of the hillslopes within catchments with complex terrain. Using a distributed hydrologic model on a number of catchments at different latitudes, where data is available for calibration and validation, we estimate the different components of the water balance to obtain the aridity index (AI = PET/P) and the evaporative index (EI = AET/P) of each slope for a number of years. We use Budyko's curve as a framework to characterize the inter-annual variability in the hydrologic response of the hillslopes in the studied catchments, developing a hydrologic sensitivity index (HSi) based on the relative change in Budyko's curve components (HSi=ΔAI/ΔEI). With this method, when the HSi values of a given hillslope are larger than 1 the hydrologic behavior of that part of the catchment is considered sensitive to changes in climatic conditions, while values approaching 0 would indicate the opposite. We use this approach as a diagnostic tool to discern the effect of aspect, elevation, and latitude on the hydrologic regime of the slopes in complex terrain catchments and to try to explain observed patterns of land cover conditions on these types of catchments.

The effects of creatine supplementation on thermoregulation and isokinetic muscular performance following acute (3-day) supplementation.

PubMed

Rosene, J M; Matthews, T D; Mcbride, K J; Galla, A; Haun, M; Mcdonald, K; Gagne, N; Lea, J; Kasen, J; Farias, C

2015-12-01

The purpose of this investigation was to determine the effects of 3 d of creatine supplementation on thermoregulation and isokinetic muscular performance. Fourteen males performed two exercise bouts following 3 d of creatine supplementation and placebo. Subjects exercised for 60 min at 60-65% of VO2max in the heat followed by isokinetic muscular performance at 60, 180, and 300°·s(-1). Dependent variables for pre- and postexercise included nude body weight, urine specific gravity, and serum creatinine levels. Total body water, extracellular water and intracellular water were measured pre-exercise. Core temperature was assessed every 5 min during exercise. Peak torque and Fatigue Index were used to assess isokinetic muscular performance. Core temperature increased during the run for both conditions. Total body water and extracellular water were significantly greater (P<0.05) following creatine supplementation. No significant difference (P>0.05) was found between conditions for intracellular water, nude body weight, urine specific gravity, and serum creatinine. Pre-exercise scores for urine specific gravity and serum creatinine were significantly less (P<0.05) versus post-exercise. No significant differences (P>0.05) were found in peak torque values or Fatigue Index between conditions for each velocity. A significant (P<0.05) overall velocity effect was found for both flexion and extension. As velocity increased, mean peak torque values decreased. Three d of creatine supplementation does not affect thermoregulation during submaximal exercise in the heat and is not enough to elicit an ergogenic effect for isokinetic muscle performance following endurance activity.

Multi-frequency bioelectrical impedance: a comparison between the Cole-Cole modelling and Hanai equations with the classical impedance index approach.

PubMed

Deurenberg, P; Andreoli, A; de Lorenzo, A

1996-01-01

Total body water and extracellular water were measured by deuterium oxide and bromide dilution respectively in 23 healthy males and 25 healthy females. In addition, total body impedance was measured at 17 frequencies, ranging from 1 kHz to 1350 kHz. Modelling programs were used to extrapolate impedance values to frequency zero (extracellular resistance) and frequency infinity (total body water resistance). Impedance indexes (height2/Zf) were computed at all 17 frequencies. The estimation errors of extracellular resistance and total body water resistance were 1% and 3%, respectively. Impedance and impedance index at low frequency were correlated with extracellular water, independent of the amount of total body water. Total body water showed the greatest correlation with impedance and impedance index at high frequencies. Extrapolated impedance values did not show a higher correlation compared to measured values. Prediction formulas from the literature applied to fixed frequencies showed the best mean and individual predictions for both extracellular water and total body water. It is concluded that, at least in healthy individuals with normal body water distribution, modelling impedance data has no advantage over impedance values measured at fixed frequencies, probably due to estimation errors in the modelled data.

Short term effect of conventional tillage and cover crops in physical and chemical properties in two olive orchards of southern Spain

NASA Astrophysics Data System (ADS)

Guzmán, Gema; Giráldez, Juan Vicente; Gómez, José Alfonso

2014-05-01

Numerous studies have attempted to assess the differences in soil properties caused by different management systems in olive cropped farms. Nevertheless the influence of the most frequent management systems on the hydraulic properties of these soils has not been evaluated. Contrarily, there are very few studies that have tried to correlate these results with soil losses due to water erosion. There are complementary approaches to traditional degradation indices, as the S index based on the form of the soil retention curve (Dexter 2004a,b,c). The objectives of this study were (i) to evaluate the methods based on the S index to assess the physical quality of soil in olive orchards, (ii) to assess the short-term changes (2 years) in soil physical and chemical properties in two olive orchards under different managements systems, namely conventional tillage and cover crop, and (iii) to formulate strategies for assessing the quality of soil in olive orchards. For the studied soils, degradation processes (associated to conventional tillage) and the improvement of their properties (linked to cover crops) showed a fast response. Chemical changes were quickly observed. However physical changes are slower than chemical changes for both soils. Water retention curves allowed the evaluation of soil porosity based on depth in the profile and the management practices. The S index was computed for every soil using the conventional soil water retention equations fitted to the experimental data. For the olive cropped soils, higher S index values were obtained in the less degradated areas, in most of the cases. Therefore, the S index could be used as a soil quality indicator although further research should be required to study its evolution at a larger temporal scale. References: Dexter, A. R. 2004. a.- Soil physical quality. PartI. Theory, effects of soil texture, density, and organic matter, and effects on root growth. Geoderma 120 (2004) 201-214. Dexter, A. R. 2004. b.- Soil physical quality. Part II. Friability, tillage, tilth and hardsetting. Geoderma 120 (2004) 215-225. Dexter, A. R. 2004. c.- Soil physical quality. Part III: Unsaturated hydraulic conductivity and general conclusions about S-theory. Geoderma 120 (2004) 227-239.

Satellite Image-based Estimates of Snow Water Equivalence in Restored Ponderosa Pine Forests in Northern Arizona

NASA Astrophysics Data System (ADS)

Sankey, T.; Springer, A. E.; O'Donnell, F. C.; Donald, J.; McVay, J.; Masek Lopez, S.

2014-12-01

The U.S. Forest Service plans to conduct forest restoration treatments through the Four Forest Restoration Initiative (4FRI) on hundreds of thousands of acres of ponderosa pine forest in northern Arizona over the next 20 years with the goals of reducing wildfire hazard and improving forest health. The 4FRI's key objective is to thin and burn the forests to create within-stand openings that "promote snowpack accumulation and retention which benefit groundwater recharge and watershed processes at the fine (1 to 10 acres) scale". However, little is known about how these openings created by restoration treatments affect snow water equivalence (SWE) and soil moisture, which are key parts of the water balance that greatly influence water availability for healthy trees and for downstream water users in the Sonoran Desert. We have examined forest canopy cover by calculating a Normalized Difference Vegetation Index (NDVI), a key indicator of green vegetation cover, using Landsat satellite data. We have then compared NDVI between treatments at our study sites in northern Arizona and have found statistically significant differences in tree canopy cover between treatments. The control units have significantly greater forest canopy cover than the treated units. The thinned units also have significantly greater tree canopy cover than the thin-and-burn units. Winter season Landsat images have also been analyzed to calculate Normalized Difference Snow Index (NDSI), a key indicator of snow water equivalence and snow accumulation at the treated and untreated forests. The NDSI values from these dates are examined to determine if snow accumulation and snow water equivalence vary between treatments at our study sites. NDSI is significantly greater at the treated units than the control units. In particular, the thinned forest units have significantly greater snow cover than the control units. Our results indicate that forest restoration treatments result in increased snow pack accumulation and this increase can be efficiently estimated at a landscape scale using satellite data.

Water footprint assessment of oil palm in Malaysia: A preliminary study

NASA Astrophysics Data System (ADS)

Muhammad-Muaz, A.; Marlia, M. H.

2014-09-01

This study evaluates the water footprint of growing oil palm in Malaysia based on the water footprint method. The crop water use was determined using the CROPWAT 8.0 model developed by the Land and Water Development Division of FAO. The total water footprint for growing oil palm is 243 m3/ton. The result of this study showed that the green water footprint is 1.5 orders of magnitude larger compared to the blue water footprint. Besides providing updated status of total water used from the oil palm plantation, our result also shows that this baseline information helps in identifying which areas need to be conserved and what type of recommendation that should be drawn. As the results of the water footprint can differ between locations, the inclusion of local water stress index should be considered in the calculation of water footprint.

The need for an improved risk index for phosphorus losses to water from tile-drained agricultural land

NASA Astrophysics Data System (ADS)

Ulén, Barbro; Djodjic, Faruk; Etana, Araso; Johansson, Göran; Lindström, Jan

2011-03-01

SummaryA refined version of a conditional phosphorus risk index (PRI) for P losses to waters was developed based on monitoring and analyses of PRI factors from an agricultural catchment in Sweden. The catchment has a hummocky landscape of heavy glacial till overlying moraine and an overall balanced soil P level. Single P source factors and combinations of factors were tested and discussed together with water movement and water management factors important for catchments dominated by drained clay soils. An empirical relationship was established (Pearson correlation coefficient 0.861, p < 0.001) between phosphorus sorption index (PSI-CaCl 2), measured in a weak calcium chloride solution, and iron (Fe-AL) aluminium (Al-AL) and phosphorus (P-AL) in soil extract with acid ammonium lactate. Differing relationships were found for a field that had not received any manure in the last 15 years and a field that had received chicken litter very recently. In addition, a general relationship (Pearson correlation coefficient 0.839, p < 0.001) was found between the ratio of phosphorus extracted from fresh soil in water (Pw) to PSI-CaCl 2 and the degree of phosphorus saturation in lactate extract (DPS-AL). One exception was a single field, representing 7% of agricultural land in the catchment, that had been treated with glyphosate shortly before soil sampling. Saturated hydraulic conductivity (SHC) in heavy clay in contact with the moraine base (at 1 m depth) was on average 0.06 m day -1. In clay not in contact with moraine, SHC was significantly lower (mean 0.007 m day -1). A reduction in the present tile drain spacing (from 14-16 m to 11 m) is theoretically required to maintain satisfactory water discharge and groundwater level. Up to 10% of the arable land was estimated to be a potential source area for P, based on different indices. Parts of a few fields close to farm buildings (1% of total arable land) were identified as essential P source areas, with high DPS-AL values and low PSI-CaCl 2 values throughout the soil profile. A further 2% of arable land was identified as potential important transport areas, based on visible surface water rills or frequent water-ponded conditions. Fields comprising 10% of the total arable land in the catchment should be re-drained in the near future to improve water infiltration and avoid unnecessary channelised water flow. The need for an improved PRI for erosion and water transport is discussed.

Photosynthetic metabolism and quality of Eugenia pyriformis Cambess. seedlings on substrate function and water levels.

PubMed

Scalon, Silvana P Q; Jeromini, Tatiane S; Mussury, Rosilda M; Dresch, Daiane M

2014-12-01

The aim of this research was to evaluate the quality and photosynthetic metabolism of "uvaia" seedlings (Eugenia pyriformis Cambess.) on different substrates and water regimes. The seeds were sown in tubes of 50 x 190 mm in the following substrates: Sand (S), Latosol + Sand (L + S) (1:1), Latosol + Sand + Semi Decomposed Poultry Litter (L + S1 + PL) ( 1:1:0.5), Latosol + Sand + Semi Decomposed Poultry Litter (L + S2 + PL) (1:2:0.5), Latosol + Bioplant® (L + B) (1:1), and the water levels assessed were 50, 75 and 100% of water retention capacity. At 60, 90, 120 and 150 days the seedlings were evaluated according to their chlorophyll index, leaf area (cm2) and Dickson Quality Index (DQI) and at 150 days their internal concentration of carbon (mol m-2 s-1), stomatal conductance (mol m-2 s-1), transpiration rate (mmol m-2 s-1), photosynthesis (µmol m-2 s-1) and efficiency of water use (µmol de CO2 / mmol de H2O). Until their 150th days, the seedlings had higher quality and photosynthetic metabolism when cultured with substrates containing latosol + sand + poultry litter on the two variations assessed and water retention capacity of 50%.

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 28, 1986.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and nonprint materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 29, 1987.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources, Supplement XIV (1983).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 23 (1985).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement XII.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement XIX (1984).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 25 (1986).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to hazardous wastes and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS). A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement XVI.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement IX.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 24 (l985).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS). A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement XIII.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS). A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement XV.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement XI.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement X.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 26, 1986.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of governmental, private concerns, and…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement XX (1984).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 22 (1985).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS). A Compilation of Abstracts to Water Quality and Water Resources Materials. Supplement XVII.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 21 (1985).

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement 27, 1986.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials, Supplement XVIII.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracted/indexed materials include all levels of government, private concerns, and educational…

Design of negative refractive index metamaterial with water droplets using 3D-printing

NASA Astrophysics Data System (ADS)

Shen, Zhaoyang; Yang, Helin; Huang, Xiaojun; Yu, Zetai

2017-11-01

We numerically and experimentally demonstrate a negative refractive index (NRI) behavior in combined water droplets and photosensitive resin materials operating in the microwave regime. The NRI is achieved over a very wide frequency range in 10.27-15 GHz with bandwidth of 4.63 GHz. The simulated results approximately agree with the experimental results. The negative index band can be controlled by water droplet radius. The proposed metamaterial production process is simple and may have potential applications in broadband tunable devices.

Effect of brewery wastewater obtained from different phases of treatment plant on seed germination of chickpea (Cicer arietinum), maize (Zea mays), and pigeon pea (Cajanus cajan).

PubMed

Salian, Rupa; Wani, Suhas; Reddy, Ramamohan; Patil, Mukund

2018-03-01

Brewing industry releases large quantities of wastewater after product generation. Brewery wastewater contains organic compounds which are biodegradable in nature. These biodegradable wastes can be recycled and reused and hence considered as suitable products for agriculture. But before using wastewater for agriculture, it is better to evaluate the phytotoxic effects of wastewater on crops. Hence, the main objective of this study is to evaluate the effects of brewery effluent on seed germination and growth parameters of selected crop species like chickpea (Cicer arietinum), maize (Zea mays), and pigeon pea (Cajanus cajan). Study comprised seven types of water treatments-tap water as control, diluted UASBR effluent (50% effluent + 50% distilled water): UASBR50, undiluted UASBR effluent: UASBR100, diluted TC effluent (50% effluent + 50% distilled water): ETP50,TC effluent without dilution: ETP100, 10% diluted reverse osmosis (RO10) reject (10% RO reject + 90% distilled water), and 25% diluted reverse osmosis(RO25) reject (25% RO reject + 75% distilled water) with three replications in completely randomized design. Germination test was performed in petri plates for 5 days. Parameters like germination percentage, germination rate index, seedling length, phytotoxicity index, seed vigor index, and biomass were calculated. All parameters decreased with increase in respective effluent concentration. Among all treatments, RO25 showed highest inhibitory effect on all three crops. Even though undiluted effluent of UASBR and ETP effluent showed positive effect on germination, seedling growth of three crops was promoted to the maximum by UASBR50 and ETP50. Hence, from the study, it was concluded that dilution of brewery effluent can be recommended before using it for irrigational purpose.

Creating a Flood Risk Index to Improve Community Resilience

NASA Astrophysics Data System (ADS)

Klima, K.; El Gammal, L.

2017-12-01

While flood risk reduction is an existent discourse and agenda in policy and insurance, vulnerabilities vary between communities; some communities may have aging infrastructure, or an older/poorer population less able to absorb a flood, putting them at increased risk from the hazards. As a result, some are considering environmental justice aspects of flood risk reduction. To date, catastrophe models have focused on creating floodmaps (e.g., NOAA's Sea Level Rise Viewer, Climate Central's Surging Seas), or on linking hydrological models to economic loss models (e.g., HEC-RAS + HAZUS). However, this approach may be highly inequitable between areas of different income (as well as other demographics). Some have begun work on combining hydrology with vulnerability information (e.g., USACE's North Atlantic Comprehensive Coastal Study). To our knowledge, no one has tried to adapt the more advanced known heat risk theory to water risk by combining hydrology information (e.g., HEC-RAS, floodplain maps) with the social vulnerability (e.g., Cutter et al.) of the residents. This project will create a method to combine water hazard data with a derived water vulnerability index to help a community understand their current and future water risk. We will use the case study area of Pittsburgh, PA, which faces severe precipitation and riverine flooding hazards. Building on present literature of factors influencing water vulnerability contextualized to the Pittsburgh region, we will identify, quantify, and map the top factors impacting water vulnerability. We will combine these with flood maps to identify the geospatial distribution of water risk. This work will allow policy makers to identify location-specific aspects of water vulnerability and risk in any community, thus promoting environmental justice. It is possible that this type of original research would create maps of relative water risk that may prove as understandable to the general public as other flood maps, and may also help to promote "just resilience". This presentation will present a method to combine water hazard data with a derived water vulnerability index to present work on the geospatial distribution of water risk in Pittsburgh, PA.

Ingestion of dug well water from an area with high prevalence of chronic kidney disease of unknown etiology (CKDu) and development of kidney and liver lesions in rats

PubMed

Thammitiyagodage, M G; Gunatillaka, M M; Ekanayaka, N; Rathnayake, C; Horadagoda, N U; Jayathissa, R; Gunaratne, U K; Kumara, W G; Abeynayake, P

2017-03-31

Chronic kidney disease of unknown aetiology (CKDu) is prevalent in the North Central Province (NCP) of Sri Lanka and ingestion of dug well water is considered a potential causative factor. Three CKDu prevalent villages were selected from the NCP based on the number of CKDu patients in the locality. Forty Wistar rats were divided into four groups with 10 rats each. Group No 1, 2 and 3 were given water from selected dug wells. Control group was given tap water from Colombo. Water samples were analysed for fluoride, iron, arsenic, cadmium and calcium. Histopathological examination of liver and kidney tissues were performed. Significant reduction of glomerular filtration rate (GFR) was observed in two test groups compared to the control group (p0.05). In one group hepatocellular carcinoma with elevated serum liver enzymes was observed whilst hepatitis was observed in another test group (p<0.05). But mixed lesions were common in all affected rats. Significantly high renal tubular lesion index was observed in all three experimental groups (p<0.05) and high glomerular lesion index (p=0.017) was observed in one test group. Cadmium, arsenic and iron contents were below detectable levels in the NCP water sources and tap water from Colombo. Different wells may have different concentrations of environmental toxins and depending on the severity of the toxin contents GFR and grade and type of liver and kidney lesions may vary. High fluoride and other undetected toxins in shallow dug wells may be the causative factors for renal and liver lesions in these Wistar rats.

Impact of Drought on Groundwater and Soil Moisture - A Geospatial Tool for Water Resource Management

NASA Astrophysics Data System (ADS)

Ziolkowska, J. R.; Reyes, R.

2016-12-01

For many decades, recurring droughts in different regions in the US have been negatively impacting ecosystems and economic sectors. Oklahoma and Texas have been suffering from exceptional and extreme droughts in 2011-2014, with almost 95% of the state areas being affected (Drought Monitor, 2015). Accordingly, in 2011 alone, around 1.6 billion were lost in the agricultural sector alone as a result of drought in Oklahoma (Stotts 2011), and 7.6 billion in Texas agriculture (Fannin 2012). While surface water is among the instant indicators of drought conditions, it does not translate directly to groundwater resources that are the main source of irrigation water. Both surface water and groundwater are susceptible to drought, while groundwater depletion is a long-term process and might not show immediately. However, understanding groundwater availability is crucial for designing water management strategies and sustainable water use in the agricultural sector and other economic sectors. This paper presents an interactive geospatially weighted evaluation model and a tool at the same time to analyze groundwater resources that can be used for decision support in water management. The tool combines both groundwater and soil moisture changes in Oklahoma and Texas in 2003-2014, thus representing the most important indicators of agricultural and hydrological drought. The model allows for analyzing temporal and geospatial long-term drought at the county level. It can be expanded to other regions in the US and the world. The model has been validated with the Palmer Drought Index Severity Index to account for other indicators of meteorological drought. It can serve as a basis for an upcoming socio-economic and environmental analysis of drought events in the short and long-term in different geographic regions.

Ecological Health and Water Quality Assessments in Big Creek Lake, AL

NASA Astrophysics Data System (ADS)

Childs, L. M.; Frey, J. W.; Jones, J. B.; Maki, A. E.; Brozen, M. W.; Malik, S.; Allain, M.; Mitchell, B.; Batina, M.; Brooks, A. O.

2008-12-01

Big Creek Lake (aka J.B. Converse Reservoir) serves as the water supply for the majority of residents in Mobile County, Alabama. The area surrounding the reservoir serves as a gopher tortoise mitigation bank and is protected from further development, however, impacts from previous disasters and construction have greatly impacted the Big Creek Lake area. The Escatawpa Watershed drains into the lake, and of the seven drainage streams, three have received a 303 (d) (impaired water bodies) designation in the past. In the adjacent ecosystem, the forest is experiencing major stress from drought and pine bark beetle infestations. Various agencies are using control methods such as pesticide treatment to eradicate the beetles. There are many concerns about these control methods and the run-off into the ecosystem. In addition to pesticide control methods, the Highway 98 construction projects cross the north area of the lake. The community has expressed concern about both direct and indirect impacts of these construction projects on the lake. This project addresses concerns about water quality, increasing drought in the Southeastern U.S., forest health as it relates to vegetation stress, and state and federal needs for improved assessment methods supported by remotely sensed data to determine coastal forest susceptibility to pine bark beetles. Landsat TM, ASTER, MODIS, and EO-1/ALI imagery was employed in Normalized Difference Vegetation Index (NDVI) and Normalized Difference Moisture Index (NDMI), as well as to detect concentration of suspended solids, chlorophyll and water turbidity. This study utilizes NASA Earth Observation Systems to determine how environmental conditions and human activity relate to pine tree stress and the onset of pine beetle invasion, as well as relate current water quality data to community concerns and gain a better understanding of human impacts upon water resources.

The nonlinear Schrödinger equation and the propagation of weakly nonlinear waves in optical fibers and on the water surface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chabchoub, A., E-mail: achabchoub@swin.edu.au; Kibler, B.; Finot, C.

2015-10-15

The dynamics of waves in weakly nonlinear dispersive media can be described by the nonlinear Schrödinger equation (NLSE). An important feature of the equation is that it can be derived in a number of different physical contexts; therefore, analogies between different fields, such as for example fiber optics, water waves, plasma waves and Bose–Einstein condensates, can be established. Here, we investigate the similarities between wave propagation in optical Kerr media and water waves. In particular, we discuss the modulation instability (MI) in both media. In analogy to the water wave problem, we derive for Kerr-media the Benjamin–Feir index, i.e. amore » nondimensional parameter related to the probability of formation of rogue waves in incoherent wave trains.« less

A Comparison of Natural and Urban Characteristics and the Development of Urban Intensity Indices Across Six Geographic Settings

USGS Publications Warehouse

Falcone, James A.; Stewart, Jana; Sobieszczyk, Steven; Dupree, Jean; McMahon, Gerard; Buell, Gary

2007-01-01

As part of the U.S. Geological Survey National Water-Quality Assessment Program, the effects of urbanization on stream ecosystems have been intensively investigated in six metropolitan areas in the United States. Approximately 30 watersheds in each area, ranging in size from 4 to 560 square kilometers (median is 50 square kilometers), and spanning a development gradient from very low to very high urbanization, were examined near Atlanta, Georgia; Raleigh, North Carolina; Denver, Colorado; Dallas-Fort Worth, Texas; Portland, Oregon; and Milwaukee-Green Bay, Wisconsin. These six studies are a continuation of three previous studies in Boston, Massachusetts; Birmingham, Alabama; and Salt Lake City, Utah. In each study, geographic information system data for approximately 300 variables were assembled to (a) characterize the environmental settings of the areas and (b) establish a consistent multimetric urban intensity index based on locally important land-cover, infrastructure, and socioeconomic variables. This paper describes the key features of urbanization and the urban intensity index for the study watersheds within each area, how they differ across study areas, and the relation between the environmental setting and the characteristics of urbanization. A number of features of urbanization were identified that correlated very strongly to population density in every study area. Of these, road density had the least variability across diverse geographic settings and most closely matched the multimetric nature of the urban intensity index. A common urban intensity index was derived that ranks watersheds across all six study areas. Differences in local natural settings and urban geography were challenging in (a) identifying consistent urban gradients in individual study areas and (b) creating a common urban intensity index that matched the site scores of the local urban intensity index in all areas. It is intended that the descriptions of the similarities and differences in urbanization and environmental settings across these study areas will provide a foundation for understanding and interpreting the effects of urbanization on stream ecosystems in the studies being conducted as part of the National Water-Quality Assessment Program.

Predominant role of water in regulating the tree-growth response to diurnal asymmetric warmin

NASA Astrophysics Data System (ADS)

Chen, Z.; Xia, J.; Cui, E.

2017-12-01

Growth of the Northern Hemisphere trees is affected by diurnal asymmetric warming, which is generally considered to touch off carbon assimilation and increment of carbon storage. Asymmetric effects of diurnal warming on vegetation greenness were validated in previous researches, however, the effect of diurnal warming on wood tissue which stores most carbon of a whole plant is still unknown. Here, we combined ring-width index (RWI), remote sensing-based normalized difference vegetation index (NDVI) and climate datasets to detect the effects of daytime and night-time warming on vegetation growth, respectively. Our results indicate that daytime warming enhances NDVI but has neutral effect on tree woody growth over the Northern Hemisphere. Response of wood growth to daytime warming is linearly regulated by soil water availability. The underlying mechanism of different response of canopy and wood growth to daytime warming may attribute to the biomass change, that is, allocation to foliage tissues increased at the expense of wood tissue under warming and water-limited conditions. Night-time warming show neutral effects on NDVI and RWI over the Northern Hemisphere, and the neutral Tmin-NDVI correlations result from the non-linear mediation of soil water availability. Our results highlight the current greening trend under daytime warming does not mean higher carbon sink capacity, the warming-drying climate may impair the large carbon sink of global forests.

Minimizing instrumentation requirement for estimating crop water stress index and transpiration of maize

USDA-ARS?s Scientific Manuscript database

Research was conducted in northern Colorado in 2011 to estimate the Crop Water Stress Index (CWSI) and actual water transpiration (Ta) of maize under a range of irrigation regimes. The main goal was to obtain these parameters with minimum instrumentation and measurements. The results confirmed that ...

River Pollution: Part II. Biological Methods for Assessing Water Quality.

ERIC Educational Resources Information Center

Openshaw, Peter

1984-01-01

Discusses methods used in the biological assessment of river quality and such indicators of clean and polluted waters as the Trent Biotic Index, Chandler Score System, and species diversity indexes. Includes a summary of a river classification scheme based on quality criteria related to water use. (JN)

Applications of Remote Sensing and In-Situ Measurements for the Purpose of Understanding Lateral Carbon Fluxes between Tidal Marshes and Connected Estuarine Waters

NASA Astrophysics Data System (ADS)

Van, U. A.; Lamb, B. T.

2016-12-01

Wetlands are biologically diverse ecosystems that provide a number of ecosystems services, including flood protection, erosion prevention, and carbon sequestration. Wetlands often act as carbon sinks because the abundant plant life in wetlands does not decompose easily in the saturated conditions, leading to carbon accumulating in wetland soils. Due to the motion of tides, however, this stored carbon can be transported to the adjacent estuary. Our study site is in the northwestern shore of the Chesapeake Bay, focusing on the Kirkpatrick Marsh and the adjacent Rhode River estuary. The goal of this project is to use remotely sensed data and in situ measurements to understand carbon fluxes between the Kirkpatrick marsh and the Rhode river estuary. Satellite earth images are obtained from the Optical Land Imager (OLI) sensor aboard the Landsat 8 satellite through the USGS Earth Explorer online interface. Landsat imagery is then processed using various spatial analysis tools to calculate for vegetation indices such as Normalized Density Vegetation Index (NDVI), Transformed Vegetation Index (TVI) and Green Normalized Density Vegetation Index (GNDVI). One goal of this project is to compare the vegetation data obtained from the different indices and find out which index can optimize the wide categorization of vegetation over the wetland. We evaluated lesser known vegetation indices (TVI and GNDVI) to compare to NDVI. Preliminary results have shown TVI to be most effective when compared against NDVI and has a correlating factor of 0.987. In addition to using marsh vegetation indices, we are using water quality indices such as the Red/Green index to compare to in-situ water samples in the Rhode River. A YSI EXO2 sensor sits at the marsh-estuary interface and continuously measures water parameters such as turbidity, depth, fDOM and chlorophyll-A. We are attempting to understand if the marsh vegetation indices, water quality indices (remote sensing), and in-situ measurements of water quality are related to one another. Initial comparison between remotely sensed NDVI data and in-situ fDOM data have a correlating factor of 0.93. Understanding the processes affecting carbon cycling within wetlands is pivotal to knowing how to manage them in the future.

A five-year analysis of MODIS NDVI and NDWI for grassland drought assessment over the central Great Plains of the United States

USGS Publications Warehouse

Gu, Yingxin; Brown, Jesslyn F.; Verdin, J.P.; Wardlow, B.

2007-01-01

A five-year (2001–2005) history of moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) data was analyzed for grassland drought assessment within the central United States, specifically for the Flint Hills of Kansas and Oklahoma. Initial results show strong relationships among NDVI, NDWI, and drought conditions. During the summer over the Tallgrass Prairie National Preserve, the average NDVI and NDWI were consistently lower (NDVI < 0.5 and NDWI < 0.3) under drought conditions than under non-drought conditions (NDVI>0.6 and NDWI>0.4). NDWI values exhibited a quicker response to drought conditions than NDVI. Analysis revealed that combining information from visible, near infrared, and short wave infrared channels improved sensitivity to drought severity. The proposed normalized difference drought index (NDDI) had a stronger response to summer drought conditions than a simple difference between NDVI and NDWI, and is therefore a more sensitive indicator of drought in grasslands than NDVI alone.

Designing basin-customized combined drought indices via feature extraction

NASA Astrophysics Data System (ADS)

Zaniolo, Marta; Giuliani, Matteo; Castelletti, Andrea

2017-04-01

The socio-economic costs of drought are progressively increasing worldwide due to the undergoing alteration of hydro-meteorological regimes induced by climate change. Although drought management is largely studied in the literature, most of the traditional drought indexes fail in detecting critical events in highly regulated systems, which generally rely on ad-hoc formulations and cannot be generalized to different context. In this study, we contribute a novel framework for the design of a basin-customized drought index. This index represents a surrogate of the state of the basin and is computed by combining the available information about the water available in the system to reproduce a representative target variable for the drought condition of the basin (e.g., water deficit). To select the relevant variables and how to combine them, we use an advanced feature extraction algorithm called Wrapper for Quasi Equally Informative Subset Selection (W-QEISS). The W-QEISS algorithm relies on a multi-objective evolutionary algorithm to find Pareto-efficient subsets of variables by maximizing the wrapper accuracy, minimizing the number of selected variables (cardinality) and optimizing relevance and redundancy of the subset. The accuracy objective is evaluated trough the calibration of a pre-defined model (i.e., an extreme learning machine) of the water deficit for each candidate subset of variables, with the index selected from the resulting solutions identifying a suitable compromise between accuracy, cardinality, relevance, and redundancy. The proposed methodology is tested in the case study of Lake Como in northern Italy, a regulated lake mainly operated for irrigation supply to four downstream agricultural districts. In the absence of an institutional drought monitoring system, we constructed the combined index using all the hydrological variables from the existing monitoring system as well as the most common drought indicators at multiple time aggregations. The soil moisture deficit in the root zone computed by a distributed-parameter water balance model of the agricultural districts is used as target variable. Numerical results show that our framework succeeds in constructing a combined drought index that reproduces the soil moisture deficit. Moreover, this index represents a valuable information for supporting appropriate drought management strategies, including the possibility of directly informing the lake operations about the drought conditions and improve the overall reliability of the irrigation supply system.

Links Between Flood Frequency and Annual Water Balance Behaviors: A Basis for Similarity and Regionalization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Jiali; Li, Hongyi; Leung, Lai-Yung R.

This paper presents the results of a data based comparative study of several hundred catchments across continental United States belonging to the MOPEX dataset, which systematically explored the connection between the flood frequency curve and measures of mean annual water balance. Two different measures of mean annual water balance are used: (i) a climatic aridity index, AI, which is a measure of the competition between water and energy availability at the annual scale; and, (ii) baseflow index, BFI, the ratio of slow runoff to total runoff also at the annual time scale, reflecting the role of geology, soils, topography andmore » vegetation. The data analyses showed that the aridity index, AI, has a first order control on both the mean and Cv of annual maximum floods. While mean annual flood decreases with increasing aridity, Cv increases with increasing aridity. BFI appeared to be a second order control on the magnitude and shape of the flood frequency curve. Higher BFI, meaning more subsurface flow and less surface flow leads to a decrease of mean annual flood whereas lower BFI leads to accumulation of soil moisture and increased flood magnitudes that arise from many events acting together. The results presented in this paper provide innovative means to delineate homogeneous regions within which the flood frequency curves can be assumed to be functionally similar. At another level, understanding the connection between annual water balance and flood frequency will be another building block towards developing comprehensive understanding of catchment runoff behavior in a holistic way.« less

Variation of MODIS reflectance and vegetation indices with viewing geometry and soybean development.

PubMed

Breunig, Fábio M; Galvão, Lênio S; Formaggio, Antônio R; Epiphanio, José C N

2012-06-01

Directional effects introduce a variability in reflectance and vegetation index determination, especially when large field-of-view sensors are used (e.g., Moderate Resolution Imaging Spectroradiometer - MODIS). In this study, we evaluated directional effects on MODIS reflectance and four vegetation indices (Normalized Difference Vegetation Index - NDVI; Enhanced Vegetation Index - EVI; Normalized Difference Water Index - NDWI(1640) and NDWI(2120)) with the soybean development in two growing seasons (2004-2005 and 2005-2006). To keep the reproductive stage for a given cultivar as a constant factor while varying viewing geometry, pairs of images obtained in close dates and opposite view angles were analyzed. By using a non-parametric statistics with bootstrapping and by normalizing these indices for angular differences among viewing directions, their sensitivities to directional effects were studied. Results showed that the variation in MODIS reflectance between consecutive phenological stages was generally smaller than that resultant from viewing geometry for closed canopies. The contrary was observed for incomplete canopies. The reflectance of the first seven MODIS bands was higher in the backscattering. Except for the EVI, the other vegetation indices had larger values in the forward scattering direction. Directional effects decreased with canopy closure. The NDVI was lesser affected by directional effects than the other indices, presenting the smallest differences between viewing directions for fixed phenological stages.

Introduction of Drought Monitoring and Forecasting System based on Real-time Water Information Using ICT

NASA Astrophysics Data System (ADS)

Lee, Y., II; Kim, H. S.; Chun, G.

2016-12-01

There were severe damages such as restriction on water supply caused by continuous drought from 2014 to 2015 in South Korea. Through this drought event, government of South Korea decided to establish National Drought Information Analysis Center in K-water(Korea Water Resources Corporation) and introduce a national drought monitoring and early warning system to mitigate those damages. Drought index such as SPI(Standard Precipitation Index), PDSI(Palmer Drought Severity Index) and SMI(Soil Moisture Index) etc. have been developed and are widely used to provide drought information in many countries. However, drought indexes are not appropriate for drought monitoring and early warning in civilized countries with high population density such as South Korea because it could not consider complicated water supply network. For the national drought monitoring and forecasting of South Korea, `Drought Information Analysis System' (D.I.A.S) which is based on the real time data(storage, flowrate, waterlevel etc.) was developed. Based on its advanced methodology, `DIAS' is changing the paradigm of drought monitoring and early warning systems. Because `D.I.A.S' contains the information of water supply network from water sources to the people across the nation and provides drought information considering the real-time hydrological conditions of each and every water source. For instance, in case the water level of a specific dam declines to predetermined level of caution, `D.I.A.S' will notify people who uses the dam as a source of residential or industrial water. It is expected to provide credible drought monitoring and forecasting information with a strong relationship between drought information and the feelings of people rely on water users by `D.I.A.S'.

Chemical composition and physicochemical properties of Phaeodactylum tricornutum microalgal residual biomass.

PubMed

German-Báez, L J; Valdez-Flores, M A; Félix-Medina, J V; Norzagaray-Valenzuela, C D; Santos-Ballardo, D U; Reyes-Moreno, C; Shelton, L M; Valdez-Ortiz, A

2017-12-01

The production of photosynthetic biofuels using microalgae is a promising strategy to combat the use of non-renewable energy sources. The microalgae residual biomass is a waste by-product of biofuel production; however, it could prove to have utility in the development of sustainable nutraceuticals and functional foods. In this study, a comprehensive characterisation of the under-utilised Phaeodactylum tricornutum microalgae residual biomass is presented. Proximal composition, antioxidant capacity (using three different antioxidant assays; oxygen radical absorbance capacity; radical cation activity, ABTS; and radical scavenging activity, DPPH), and total phenolic content of free and bound polyphenols were determined. Additionally, the physicochemical properties of water activity, pH, water absorption index, water solubility index, and dispersibility were evaluated. Results revealed that P. tricornutum microalgae residual biomass exhibits a relatively high protein and carbohydrate content, with values of 36.67% and 46.78%, respectively; and most carbohydrates were found as total dietary fibre (45.57%), of which insoluble dietary fibre was the most predominant (43.54%). Antioxidant capacity values for total phytochemicals of 106.22, 67.93, 9.54 µM TE g -1 dw were determined by oxygen radical absorbance capacity, ABTS, and DPPH assays, respectively. Total phenolic content was found to be 2.90 mg GAE g -1 dw. Interestingly, antioxidant capacity and total phenolic content were higher in bound than in free phytochemical extracts. The physicochemical analysis showed P. tricornutum microalgae residual biomass to have suitable properties for the generation of a beverage with Aw, pH, water absorption index, water solubility index, and dispersibility values of 0.45, 7.12, 3.40 g gel g -1  dw, 2.5 g solids 100 g -1  dw, and 90%, respectively. Hence, P. tricornutum microalgae residual biomass could be considered a potential source of bioactive compounds suitable for the production of functional food exhibiting antioxidant capacity and high dietary fibre content.

[Distribution and risk assessment of mercury species in soil of the water-level-fluctuating zone in the Three Gorges Reservoir].

PubMed

Zhang, Cheng; Chen, Hong; Wang, Ding-Yong; Sun, Rong-Guo; Zhang, Jin-Yang

2014-03-01

To investigate pollution level and ecological risk of mercury in soils of the water-level-fluctuating zone in the Three Gorges Reservoir Region, 192 surface soil samples from 14 counties (districts) in Chongqing were obtained. Concentrations of THg and Hg species, bioavailable Hg were analyzed and discussed. Geoaccumulation index (I(geo)) and Håkanson potential ecological risk index (E(r)) were applied to assess the pollution status and potential ecological risk of THg and Hg species, respectively. The results showed that significant differences in the concentration of THg were found in soils of water-level-fluctuating zone in the Three Gorges Reservoir. The THg concentration ranged from 22.4 to 393.5 microg x kg(-1), with an average of (84.2 +/- 54.3) microg x kg(-1). 76.6% of the samples' THg content was higher than the soil background value in the Three Gorges Reservoir Region. The percentage of five mercury species (water-soluble Hg, HCl-soluble Hg, KOH-soluble Hg, H2O2-soluble Hg, residue Hg) in soils were 4.1%, 15.5%, 18.3%, 10.9%, 51.3%, respectively. The average concentrations of bioavailable mercury varied between 19.7-36.6 microg x kg(-1), and the percentage of bioavailable Hg was 22.1%-51.6% of THg. According to the geoaccumulation index, the soils were lightly polluted by Hg. Håkanson single potential ecological risk index evaluation showed that Hg species had a low potential ecological risk, moreover, soils of water-level-fluctuating zone in the Three Gorges Reservoir were at low ecological risk levels as evaluated by bioavailable Hg. While, the assessment results based on THg of soils was much higher than that based on the Hg species. Two methods of evaluation showed that the I(geo) and E(r) values calculated based on the Hg species better reflected the actual pollution levels of soils and its hazard to aquatic organisms.

Characterization of cells and bacteria by photophoretic velocimetry

NASA Astrophysics Data System (ADS)

Helmbrecht, Clemens; Niessner, Reinhard; Haisch, Christoph

2008-02-01

The migration induced by intensive light is termed photophoresis. We could show that the evaluation of light-induced velocities of microparticles, bacteria and cells suspended in water is valuable for the prediction of their intrinsic properties. Two different laser setups were evaluated for photophoretic migration, a He-Ne laser (P = 45 mW, λ = 633 nm) and a diode-pumped cw-Nd:YAG (P = 1.1 W, λ = 532 nm). When analyzing the migration behavior of particles, we find significant differences depending on both, geometrical size and refractive index. We describe migration of PS particles of different size as well as with different refractive index but same diameter, SiO II and melamine resin. The potential for the separation of biological matter is shown as velocity distributions of heat killed bacteria of Escherichia coli, Salmonella enteritidis, and baker's yeast is reported.

[Soil moisture estimation method based on both ground-based remote sensing data and air temperature in a summer maize ecosystem.

PubMed

Wang, Min Zheng; Zhou, Guang Sheng

2016-06-01

Soil moisture is an important component of the soil-vegetation-atmosphere continuum (SPAC). It is a key factor to determine the water status of terrestrial ecosystems, and is also the main source of water supply for crops. In order to estimate soil moisture at different soil depths at a station scale, based on the energy balance equation and the water deficit index (WDI), a soil moisture estimation model was established in terms of the remote sensing data (the normalized difference vegetation index and surface temperature) and air temperature. The soil moisture estimation model was validated based on the data from the drought process experiment of summer maize (Zea mays) responding to different irrigation treatments carried out during 2014 at Gucheng eco-agrometeorological experimental station of China Meteorological Administration. The results indicated that the soil moisture estimation model developed in this paper was able to evaluate soil relative humidity at different soil depths in the summer maize field, and the hypothesis was reasonable that evapotranspiration deficit ratio (i.e., WDI) linearly depended on soil relative humidity. It showed that the estimation accuracy of 0-10 cm surface soil moisture was the highest (R 2 =0.90). The RMAEs of the estimated and measured soil relative humidity in deeper soil layers (up to 50 cm) were less than 15% and the RMSEs were less than 20%. The research could provide reference for drought monitoring and irrigation management.

Study of hydrological extremes - floods and droughts in global river basins using satellite data and model output

NASA Astrophysics Data System (ADS)

Lakshmi, V.; Fayne, J.; Bolten, J. D.

2016-12-01

We will use satellite data from TRMM (Tropical Rainfall Measurement Mission), AMSR (Advanced Microwave Scanning Radiometer), GRACE (Gravity Recovery and Climate Experiment) and MODIS (Moderate Resolution Spectroradiometer) and model output from NASA GLDAS (Global Land Data Assimilation System) to understand the linkages between hydrological variables. These hydrological variables include precipitation soil moisture vegetation index surface temperature ET and total water. We will present results for major river basins such as Amazon, Colorado, Mississippi, California, Danube, Nile, Congo, Yangtze Mekong, Murray-Darling and Ganga-Brahmaputra.The major floods and droughts in these watersheds will be mapped in time and space using the satellite data and model outputs mentioned above. We will analyze the various hydrological variables and conduct a synergistic study during times of flood and droughts. In order to compare hydrological variables between river basins with vastly different climate and land use we construct an index that is scaled by the climatology. This allows us to compare across different climate, topography, soils and land use regimes. The analysis shows that the hydrological variables derived from satellite data and NASA models clearly reflect the hydrological extremes. This is especially true when data from different sensors are analyzed together - for example rainfall data from TRMM and total water data from GRACE. Such analyses will help to construct prediction tools for water resources applications.

Characterization of water molecular state in in-vivo thick tissues using diffuse optical spectroscopic imaging

NASA Astrophysics Data System (ADS)

Chung, So Hyun

Structural changes in water molecules are related to physiological, anatomical and pathological properties of tissues. Near infrared (NIR) optical absorption methods are sensitive to water; however, detailed characterization of water in thick tissues is difficult to achieve because subtle spectral shifts can be obscured by multiple light scattering. In the NIR, a water absorption peak is observed around 975 nm. The precise NIR peak's shape and position are highly sensitive to water molecular disposition. A bound water index (BWI) was developed that quantifies the spectral shift and shape changes observed in tissue water absorption spectra measured by broadband diffuse optical spectroscopic imaging (DOSI). DOSI quantitatively measures light absorption and scattering spectra in cm-deep tissues and therefore reveals bound water spectral shifts. BWI as a water state index was validated by comparing broadband DOSI to MRI and a conductivity cell using bound water phantoms. Non-invasive BWI measurements of malignant and normal tissues in 18 subjects showed a significantly higher fraction of free water in malignant tissues (p<0.0001) compared to normal tissues. BWI showed potential as a prognostic index based on high correlations with tumor grade and size. An algorithm for absolute temperature measurements in deep tissues was developed based on resolving opposing effects of water vibrational frequency shifts due to macromolecular binding. DOSI measures absolute temperature with a difference of 1.1+/-0.91°C from a thermistor. Deep tissue temperature measured in forearms during cold-stress was consistent with previously reported invasively-measured deep tissue temperature. Finally, the BWI was compared to Apparent Diffusion Coefficient (ADC) of diffusion weighted MRI in 9 breast cancer patients. The BWI and ADC correlated (R=0.8, p=<0.01) and both parameters decreased with increasing bulk water content in cancer tissues. Although BWI and ADC are positively correlated in vivo, BWI appears to be more sensitive to free water in the extracellular matrix while ADC reflects increased tumor cellularity. The relationship between ADC, BWI and bulk water concentration suggests that both parameters have potential for assessing tumor histopathological grade. My results confirm the importance of water as a critical tissue component that can potentially provide unique insight into the molecular pathophysiology of cancer.

Water quality evaluation system to assess the status and the suitability of the Citarum river water to different uses.

PubMed

Fulazzaky, Mohamad Ali

2010-09-01

Water quality degradation in the Citarum river will increase from the year to year due to increasing pollutant loads when released particularly from Bandung region of the upstream areas into the river without treatment. This will be facing the problems on water quality status to use for multi-purposes in the downstream areas. The water quality evaluation system is used to evaluate the available water condition that distinguishes into two categories, i.e., the water quality index (WQI) and water quality aptitude (WQA). The assessment of water quality for the Citarum river from 10 selected stations was found that the WQI situates in the bad category generally and the WQA ranges from the suitable quality for agriculture and livestock watering uses to the unsuitable for biological potential function, drinking water production, and leisure activities and sports in the upstream areas of Saguling dam generally.

33 CFR 52.81 - Reading room and index.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Reading room and index. 52.81 Section 52.81 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Public Access to Decisions § 52.81 Reading room and index. After deleting only so much...

33 CFR 52.81 - Reading room and index.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Reading room and index. 52.81 Section 52.81 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Public Access to Decisions § 52.81 Reading room and index. After deleting only so much...

33 CFR 52.81 - Reading room and index.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Reading room and index. 52.81 Section 52.81 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Public Access to Decisions § 52.81 Reading room and index. After deleting only so much...

33 CFR 52.81 - Reading room and index.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Reading room and index. 52.81 Section 52.81 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Public Access to Decisions § 52.81 Reading room and index. After deleting only so much...

33 CFR 52.81 - Reading room and index.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Reading room and index. 52.81 Section 52.81 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PERSONNEL BOARD FOR CORRECTION OF MILITARY RECORDS OF THE COAST GUARD Public Access to Decisions § 52.81 Reading room and index. After deleting only so much...

Development of an Integrated Moisture Index for predicting species composition

Treesearch

Louis R. Iverson; Charles T. Scott; Martin E. Dale; Anantha Prasad

1996-01-01

A geographic information system (GIS) approach was used to develop an Integrated Moisture Index (IMI), which was used to predict species composition for Ohio forests. Several landscape features (a slope-aspect shading index, cumulative flow of water downslope, curvature of the landscape, and the water-holding capacity of the soil) were derived from elevation and soils...

Spatial Variability in Condition of Southern Rock Lobsters (Jasus edwardsii) at the Start of the Tasmanian Fishing Season.

PubMed

Mendo, Tania; Simon, Cedric; Green, Bridget; Gardner, Caleb

2016-01-01

The southern rock lobster (Jasus edwardsii) industry in Australia favours red lobsters, which are usually caught in shallow waters, over paler (brindle) lobsters. This preference is driven partly by the Chinese market, where red is associated with luck and prosperity, and additionally, by the widely held perception within the industry that brindles have greater mortality rates during out of water transport than reds. Limited scientific evidence supports these industry observations; however, these studies did not evaluate the initial condition of lobsters. This study aimed first, to determine which variables better describe condition in J. edwardsii and second, to compare condition among lobsters in several sites around Tasmania at the typical time of high transport mortality. Male lobsters were collected from the South West, South East, East and North coast of Tasmania in late November/December 2014, which correspond to the start of the Tasmanian fishing season. A comprehensive condition assessment was applied by measuring tissue proximal composition, Brix index, Total Haemocyte Count, pH, haemocyanin and another 16 haemolymph parameters of interest. A useful framework to compare condition in J. edwardsii was established by first, using Brix index as a measure of nutritional condition, second, using pH, magnesium, and bicarbonate to evaluate differences in physiological condition and finally, using THC counts as a proxy for lobster health condition. Lobsters from different sites had different nutritional, physiological and health condition, consistent with industry observations, however our results indicate that some red shallow water lobsters exhibited poorer nutritional and health condition, while some deep water brindle lobsters were in good condition. Differences in condition could not be directly associated to catch depth of lobsters and was related to other spatially discrete factors which sometimes vary over distances <3 km.

Spatial Variability in Condition of Southern Rock Lobsters (Jasus edwardsii) at the Start of the Tasmanian Fishing Season

PubMed Central

Simon, Cedric; Green, Bridget; Gardner, Caleb

2016-01-01

The southern rock lobster (Jasus edwardsii) industry in Australia favours red lobsters, which are usually caught in shallow waters, over paler (brindle) lobsters. This preference is driven partly by the Chinese market, where red is associated with luck and prosperity, and additionally, by the widely held perception within the industry that brindles have greater mortality rates during out of water transport than reds. Limited scientific evidence supports these industry observations; however, these studies did not evaluate the initial condition of lobsters. This study aimed first, to determine which variables better describe condition in J. edwardsii and second, to compare condition among lobsters in several sites around Tasmania at the typical time of high transport mortality. Male lobsters were collected from the South West, South East, East and North coast of Tasmania in late November/December 2014, which correspond to the start of the Tasmanian fishing season. A comprehensive condition assessment was applied by measuring tissue proximal composition, Brix index, Total Haemocyte Count, pH, haemocyanin and another 16 haemolymph parameters of interest. A useful framework to compare condition in J. edwardsii was established by first, using Brix index as a measure of nutritional condition, second, using pH, magnesium, and bicarbonate to evaluate differences in physiological condition and finally, using THC counts as a proxy for lobster health condition. Lobsters from different sites had different nutritional, physiological and health condition, consistent with industry observations, however our results indicate that some red shallow water lobsters exhibited poorer nutritional and health condition, while some deep water brindle lobsters were in good condition. Differences in condition could not be directly associated to catch depth of lobsters and was related to other spatially discrete factors which sometimes vary over distances <3 km. PMID:27846289

Fluorosis and dental caries in Mexican schoolchildren residing in areas with different water fluoride concentrations and receiving fluoridated salt.

PubMed

García-Pérez, A; Irigoyen-Camacho, M E; Borges-Yáñez, A

2013-01-01

To explore the association between fluoride in drinking water and the prevalence and severity of fluorosis and dental caries in children living in communities receiving fluoridated salt. Participants were schoolchildren (n = 457) living in two rural areas of the State of Morelos, Mexico, where the water fluoride concentration was 0.70 or 1.50 ppm. Dental caries status was assessed using Pitts' criteria. Lesions that were classified as D3 (decayed) were identified to determine the decayed, missing, and filled teeth index (D3MFT). Fluorosis was assessed using the Thylstrup-Fejerskov Index (TFI). Information regarding drinking water source and oral hygiene practices (tooth brushing frequency, dentifrice use, and oral hygiene index) was obtained. The prevalence of fluorosis (TFI ≥1) in communities with 0.70 and 1.50 ppm water fluoride was 39.4 and 60.5% (p = 0.014), respectively, while the prevalence of more severe forms (TFI ≥4) was 7.9 and 25.5% (p < 0.001), respectively. The mean D3MFT was 0.49 (±1.01) in the 0.70 ppm community and 0.61 (±1.47) in the 1.50 ppm community (p = 0.349). A logistic regression model for caries (D3 >1) showed that higher fluorosis categories (TFI 5-6 OR = 6.81, p = 0.001) were associated with higher caries experience, adjusted by age, number of teeth present, tooth brushing frequency, bottled water use, and natural water fluoride concentration. The prevalence of fluorosis was associated with the water fluoride concentration. Fluorosis at moderate and severe levels was associated with a higher prevalence of dental caries, compared with lesser degrees of fluorosis. The impact of dental fluorosis should be considered in dental public health programs. Copyright © 2013 S. Karger AG, Basel.

Impact of dynamic distribution of floc particles on flocculation effect.

PubMed

Nan, Jun; He, Weipeng; Song, Xinin; Li, Guibai

2009-01-01

Polyaluminum chloride (PAC) was used as coagulant and suspended particles in kaolin water. Online instruments including turbidimeter and particle counter were used to monitor the flocculation process. An evaluation model for demonstrating the impact on the flocculation effect was established based on the multiple linear regression analysis method. The parameter of the index weight of channels quantitatively described how the variation of floc particle population in different size ranges cause the decrement of turbidity. The study showed that the floc particles in different size ranges contributed differently to the decrease of turbidity and that the index weight of channel could excellently indicate the impact degree of floc particles dynamic distribution on flocculation effect. Therefore, the parameter may significantly benefit the development of coagulation and sedimentation techniques as well as the optimal coagulant selection.

Wetting behavior of selected crude oil/brine/rock systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-04-01

Of the many methods of characterizing wettability of a porous medium, the most commonly used are the Amott test and the USBM test. The Amott test does not discriminate adequately between systems that give high values of wettability index to water and are collectively described as very strongly water-wet. The USBM test does not recognize systems that achieve residual oil saturation by spontaneous imbibition. For such systems, and for any systems that exhibit significant spontaneous imbibition, measurements of imbibition rate provide a useful characterization of wettability. Methods of interpreting spontaneous imbibition data are reviewed and a new method of quantifyingmore » wettability from rate of imbibition is proposed. Capillary pressure is the driving force in spontaneous imbibition. The area under an imbibition curve is closely related to the work of displacement that results from decrease in surface free energy. Imbibition rate data can be correlated to allow for differences in interracial tension, viscosities, pore structure, and sample size. Wettability, the remaining key factor in determining the capillary driving force and the related imbibition rate, then largely determines the differences in saturation vs. scaled time curves. These curves are used to obtain pseudo imbibition capillary pressure curves; a wettability index based on relative areas under these curves is defined as the relative pseudo work of imbibition. The method is applied for two crude oil/brine/rock systems. Comparison of the method with the Amott wettability index is made for different wettability states given by differences in aging of cores with crude oil. Correlations of wettability indices with waterflood recoveries are presented.« less

Hydration-dependent dynamics of water in calcium-silicate-hydrate: A QENS study by global model.

PubMed

Le, Peisi; Fratini, Emiliano; Chen, Sow-Hsin

2018-02-02

In a saturated cement paste, there are three different types of water: the structural water chemically reacted with cement, the constrained water absorbed to the surface of the pores, and the free water in the center of the pores. Each type has different physicochemical state and unique relation to cement porosity. The different water types have different dynamics which can be detected using quasi-elastic neutron scattering (QENS). Since the porosity of a hardened cement paste is impacted strongly by the water to cement ratio (w/c), it should be possible to extract the hydration dependence of the pores by exploiting the dynamical parameters of the confined water. Three C-S-H samples with different water levels, 8%, 17% and 30% were measured using QENS. The measurements were carried out in the scattering vector, Q, range from 0.5 Å -1 to 1.3 Å -1 , and in the temperature interval from 230 K to 280 K. The data were analyzed using a novel global model developed for cement QENS spectra. The results show that while increasing the water content, the structural water index (SWI) decreases and the confining radius, a, increases. Both SWI and a have a linear relationship with the water content. The Arrhenius plot of the translational relaxation time shows that the constrained water dominates the non-structural water at water contents lower than 17%. The rotational activation energy is smaller for lower water content. The analysis demonstrated that our newly proposed global model is practical and useful for analyzing cement QENS data. Copyright © 2018 Elsevier B.V. All rights reserved.

The Assessment of Biological and Pollution Index of Estuaries Around Port of Tanjung Emas Semarang

NASA Astrophysics Data System (ADS)

Tjahjono, A.; Wahyuni, O.; Purwantini, S.

2018-02-01

Estuary is a place of accumulation of the population’s actitivites produced by domestic, industry or agriculture. This research was conducted to three of estuary of the rivers around the waters of Port of Tanjung Emas Semarang (PTES). They were estuaries of Baru river, Banjir Kanal Timur (BKT) and Siangker in west monsoon from October to December 2015. The purpose of this research was to analyze pollution index, the abundance of microorganisms either phytoplankton or zooplankton, the content of heavy metal in sediment and sea water, biological index that included diversity (H), uniformity (e), dominance (D), Saprobik Index (SI), and the Total of Saprobik Index (TSI) in the waters either HTL (High Tide Level) or LTL (Low Tide Level). The concentration of heavy metal in both sea water and sediments were analyzed by using Atomic Absorption Spectrophotometer (AAS). The result obtained from 12 parameters which were tested showed that the three waters can be categorized at heavily polluted condition at each value from 12.52 to 24.98. The concentration of heavy metal at sea water during HTW and LTW ranging from Cd is around 0.033 and 0. 048 mg/kg, Cu 0.047 and 0.07 mg/kg, Pb 0.48 and 0.71 mg/kg, and Zn 0.043 and 0.057 mg/kg. The saprobity value index based on the existence of phytoplankton or zooplankton was ranging of Oligosaprobik at low pollution or has not been polluted yet.

Remote Sensing of Water Quality in the Niger River Basin

NASA Astrophysics Data System (ADS)

Mueller, C.; Palacios, S. L.; Milesi, C.; Schmidt, C.; Baney, O. N.; Mitchell, Å. R.; Kislik, E.; Palmer-Moloney, L. J.

2015-12-01

An overarching goal of the National Geospatial Intelligence Agency (NGA) Anticipatory Analytics- -GEOnarrative program is to establish water linkages with energy, food, and climate and to understand how these linkages relate to national security and stability. Recognizing that geopolitical stability is tied to human health, agricultural productivity, and natural ecosystems' vitality, NGA partnered with NASA Ames Research Center to use satellite remote sensing to assess water quality in West Africa, specifically the Niger River Basin. Researchers from NASA Ames used MODIS and Landsat imagery to apply two water quality indices-- the Floating Algal Index (FAI) and the Turbidity Index (TI)--to large rivers, lakes and reservoirs within the Niger Basin. These indices were selected to evaluate which observations were most suitable for monitoring water quality in a region where coincident in situ measurements are not available. In addition, the FAI and TI indices were derived using data from the Hyperspectral Imagery for the Coastal Ocean (HICO) sensor for Lake Erie in the United States to determine how increased spectral resolution and in-situ measurements would improve the ability to measure the spatio-temporal variations in water quality. Results included the comparison of outputs from sensors with different spectral and spatial resolution characteristics for water quality monitoring. Approaches, such as the GEOnarrative, that incorporate water quality will enable analysts and decision-makers to recognize the current and potentially future impacts of changing water quality on regional security and stability.

Large-scale vegetation responses to terrestrial moisture storage changes

NASA Astrophysics Data System (ADS)

Andrew, Robert L.; Guan, Huade; Batelaan, Okke

2017-09-01

The normalised difference vegetation index (NDVI) is a useful tool for studying vegetation activity and ecosystem performance at a large spatial scale. In this study we use the Gravity Recovery and Climate Experiment (GRACE) total water storage (TWS) estimates to examine temporal variability of the NDVI across Australia. We aim to demonstrate a new method that reveals the moisture dependence of vegetation cover at different temporal resolutions. Time series of monthly GRACE TWS anomalies are decomposed into different temporal frequencies using a discrete wavelet transform and analysed against time series of the NDVI anomalies in a stepwise regression. The results show that combinations of different frequencies of decomposed GRACE TWS data explain NDVI temporal variations better than raw GRACE TWS alone. Generally, the NDVI appears to be more sensitive to interannual changes in water storage than shorter changes, though grassland-dominated areas are sensitive to higher-frequencies of water-storage changes. Different types of vegetation, defined by areas of land use type, show distinct differences in how they respond to the changes in water storage, which is generally consistent with our physical understanding. This unique method provides useful insight into how the NDVI is affected by changes in water storage at different temporal scales across land use types.

Vegetation Cover Change in Yellowstone National Park Detected Using Landsat Satellite Image Analysis

NASA Technical Reports Server (NTRS)

Potter, Christopher S.

2015-01-01

Results from Landsat satellite image analysis since 1987 in all unburned areas (since the 1880s) of Yellowstone National Park (YNP) showed that consistent decreases in the normalized difference vegetation index (NDVI) have been strongly dependent on periodic variations in peak annual snow water equivalents (SWE).

Sex-specific differences of craniofacial traits in Croatia: the impact of environment in a small geographic area.

PubMed

Buretic-Tomljanovic, Alena; Giacometti, Jasminka; Ostojic, Sasa; Kapovic, Miljenko

2007-01-01

Craniometric variation in humans reflects different genetic and environmental influences. Long-term climatic adaptation is less likely to show an impact on size and shape variation in a small local area than at the global level. The aim of this work was to assess the contribution of the particular environmental factors to body height and craniofacial variability in a small geographic area of Croatia. A total of 632 subjects, aged 18-21, participated in the survey. Body height, head length, head breadth, head height, head circumference, cephalic index, morphological face height, face breadth, and facial index were analysed regarding geographic, climatic and dietary conditions in different regions of the country, and correlated with the specific climatic variables (cumulative multiyear sunshine duration, cumulative multiyear average precipitation, multiyear average air temperatures) and calcium concentrations in drinking water. Significant differences between groups classified according to geographic, climatic or dietary affiliation, and the impact of the environmental predictors on the variation in the investigated traits were assessed using multiple forward stepwise regression analyses. Higher body height measures in both sexes were significantly correlated with Mediterranean diet type. Mediterranean diet type also contributed to higher head length and head circumference measures in females. Cephalic index values correlated to geographic regions in both sexes, showing an increase from southern to eastern Croatia. In the same direction, head length significantly decreased in males and head breadth increased in females. Mediterranean climate was associated with higher and narrower faces in females. The analysis of the particular climatic variables did not reveal a significant influence on body height in either sex. Concurrently, climatic features influenced all craniofacial traits in females and only head length and facial index in males. Mediterranean climate, characterized by higher average sunshine duration, higher average precipitation and higher average air temperatures, was associated with longer, higher and narrower skulls, higher head circumference, lower cephalic index, and higher and narrower faces (lower facial index). Calcium concentrations in drinking water did not correlate significantly with any dependent variable. A significant effect of environmental factors on body height and craniofacial variability was found in Croatian young adult population. This effect was more pronounced in females, revealing sex-specific craniofacial differentiation. However, the impact of environment was low and may explain only 1.0-7.32% variation of the investigated traits.

Water Quality Instructional Resources Information System (IRIS): A Compilation of Abstracts to Water Quality and Water Resources Materials. Includes May 1979 edition and Supplements 1-15.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.

Compiled are abstracts and indexes to selected print and non-print materials related to wastewater treatment and water quality education and instruction, as well as materials related to pesticides, hazardous wastes, and public participation. Sources of abstracts/indexed materials include all levels of government, private concerns, and educational…

Dendrochronological assessment of drought severity indices for Panola Mountain Research Watershed, Georgia, U.S.A.

NASA Astrophysics Data System (ADS)

McKee, A.; Aulenbach, B. T.

2015-12-01

Quantifying the relation between drought severity and tree growth is important to predict future growth rates as climate change effects the frequency and severity of future droughts. Two commonly used metrics of drought severity are the Standardized Precipitation Index (SPI) and the Palmer Drought Severity Index (PDSI). These indices are often calculated from proximal weather station data and therefore may not be very accurate at the local watershed scale. The accuracy of these commonly used measures of drought severity was compared to a recently developed, locally calibrated model of water limitation based on the difference between potential and actual evapotranspiration (ETDIFF). Relative accuracies of the drought indices were assessed on the strength of correlations with a 20-year tree-ring index chronology (1986-2006) developed from 22 loblolly pine (Pinus taeda) trees in water-limited landscape positions at the Panola Mountain Research Watershed (PMRW), a 41-hectare forested watershed located in north-central Georgia. We used SPI and PDSI index values from the weather station located at the Atlanta Airport, approximately 36 kilometers from PMRW. ETDIFF was calculated based on precipitation, temperature, runoff, and solar radiation data collected at PMRW. Annual index values for all three drought indices were calculated as the mean value over the growing season (May to September). All three indices had significant Pearson correlations with the tree-ring index (p = 0.044, 0.007, 0.002 for SPI, PDSI, and ETDIFF, respectively). The ETDIFF method had the strongest correlation (R2 = 0.40) compared to SPI and PDSI results (R2 = 0.19 and 0.32, respectively). Results suggest SPI and PDSI provided a general measure of drought conditions, however, the locally calibrated model of water limitation appears to measure drought severity more accurately. Future studies on the ecological effects of drought may benefit from adopting ETDIFF as a measure of drought severity.

Study on Remote Sensing Image Characteristics of Ecological Land: Case Study of Original Ecological Land in the Yellow River Delta

NASA Astrophysics Data System (ADS)

An, G. Q.

2018-04-01

Takes the Yellow River Delta as an example, this paper studies the characteristics of remote sensing imagery with dominant ecological functional land use types, compares the advantages and disadvantages of different image in interpreting ecological land use, and uses research results to analyse the changing trend of ecological land in the study area in the past 30 years. The main methods include multi-period, different sensor images and different seasonal spectral curves, vegetation index, GIS and data analysis methods. The results show that the main ecological land in the Yellow River Delta included coastal beaches, saline-alkaline lands, and water bodies. These lands have relatively distinct spectral and texture features. The spectral features along the beach show characteristics of absorption in the green band and reflection in the red band. This feature is less affected by the acquisition year, season, and sensor type. Saline-alkali land due to the influence of some saline-alkaline-tolerant plants such as alkali tent, Tamarix and other vegetation, the spectral characteristics have a certain seasonal changes, winter and spring NDVI index is less than the summer and autumn vegetation index. The spectral characteristics of a water body generally decrease rapidly with increasing wavelength, and the reflectance in the red band increases with increasing sediment concentration. In conclusion, according to the spectral characteristics and image texture features of the ecological land in the Yellow River Delta, the accuracy of image interpretation of such ecological land can be improved.

Climatological Modeling of Monthly Air Temperature and Precipitation in Egypt through GIS Techniques

NASA Astrophysics Data System (ADS)

El Kenawy, A.

2009-09-01

This paper describes a method for modeling and mapping four climatic variables (maximum temperature, minimum temperature, mean temperature and total precipitation) in Egypt using a multiple regression approach implemented in a GIS environment. In this model, a set of variables including latitude, longitude, elevation within a distance of 5, 10 and 15 km, slope, aspect, distance to the Mediterranean Sea, distance to the Red Sea, distance to the Nile, ratio between land and water masses within a radius of 5, 10, 15 km, the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Water Index (NDWI), the Normalized Difference Temperature Index (NDTI) and reflectance are included as independent variables. These variables were integrated as raster layers in MiraMon software at a spatial resolution of 1 km. Climatic variables were considered as dependent variables and averaged from quality controlled and homogenized 39 series distributing across the entire country during the period of (1957-2006). For each climatic variable, digital and objective maps were finally obtained using the multiple regression coefficients at monthly, seasonal and annual timescale. The accuracy of these maps were assessed through cross-validation between predicted and observed values using a set of statistics including coefficient of determination (R2), root mean square error (RMSE), mean absolute error (MAE), mean bias Error (MBE) and D Willmott statistic. These maps are valuable in the sense of spatial resolution as well as the number of observatories involved in the current analysis.

Caries and fluoridated water in two Brazilian municipalities with low prevalence of the disease.

PubMed

Cruz, Mariângela Guanaes Bortolo da; Narvai, Paulo Capel

2018-04-09

To analyze the association between exposure to fluoridated water and dental caries in a context of widespread use of fluoride toothpaste in Brazil, in a scenario of low prevalence of the disease. This is a cross-sectional observational study, of the census type, in the form of a double population-based epidemiological survey carried out in two municipalities of the state of São Paulo in 2014. The sample consisted of adolescents aged 11 and 12 years, exposed (n = 184) or not exposed (n = 128) to fluoridated water for at least five years. The populations studied lived in communities of the same geographic region and had small demographic size and similar socioeconomic classification, differing only in the exposure (Silveiras) or not exposure (São José do Barreiro) to fluoridated water. The experience, magnitude, and degree of polarization of dental caries in these populations were analyzed using the DMFT and SiC indexes, and the association was tested using Pearson's chi-square statistics and prevalence ratio between those not exposed and those exposed to fluoridated water. Although caries experience (DMFT ≥ 1) was not associated with exposure to fluoridated water (chi-square = 1.78; p = 0.18; α = 5%), a significant difference was observed in the magnitude with which the disease reached the population: the means of DMFT were 1.76 in those exposed and 2.60 in those not exposed and the means of SiC were 4.04 and 6.16, respectively. The degree of polarization, indicated by the percentage of subjects with DMFT = 0, was different, being it higher (41.8%) in subjects exposed and lower (34.3%) in subjects not exposed. The prevalence ratio between those not exposed and those exposed was 1.13, indicating little expressiveness in prevalence difference. Exposure to fluoridated water implied lower mean values for the DMFT and SiC indexes, even in the presence of the concomitant exposure to fluoridated toothpaste, in a scenario of low prevalence of the disease, and with a similar pattern of caries distribution in the populations analyzed.

Caries and fluoridated water in two Brazilian municipalities with low prevalence of the disease

PubMed Central

da Cruz, Mariângela Guanaes Bortolo; Narvai, Paulo Capel

2018-01-01

ABSTRACT OBJECTIVE To analyze the association between exposure to fluoridated water and dental caries in a context of widespread use of fluoride toothpaste in Brazil, in a scenario of low prevalence of the disease. METHODS This is a cross-sectional observational study, of the census type, in the form of a double population-based epidemiological survey carried out in two municipalities of the state of São Paulo in 2014. The sample consisted of adolescents aged 11 and 12 years, exposed (n = 184) or not exposed (n = 128) to fluoridated water for at least five years. The populations studied lived in communities of the same geographic region and had small demographic size and similar socioeconomic classification, differing only in the exposure (Silveiras) or not exposure (São José do Barreiro) to fluoridated water. The experience, magnitude, and degree of polarization of dental caries in these populations were analyzed using the DMFT and SiC indexes, and the association was tested using Pearson’s chi-square statistics and prevalence ratio between those not exposed and those exposed to fluoridated water. RESULTS Although caries experience (DMFT ≥ 1) was not associated with exposure to fluoridated water (chi-square = 1.78; p = 0.18; α = 5%), a significant difference was observed in the magnitude with which the disease reached the population: the means of DMFT were 1.76 in those exposed and 2.60 in those not exposed and the means of SiC were 4.04 and 6.16, respectively. The degree of polarization, indicated by the percentage of subjects with DMFT = 0, was different, being it higher (41.8%) in subjects exposed and lower (34.3%) in subjects not exposed. The prevalence ratio between those not exposed and those exposed was 1.13, indicating little expressiveness in prevalence difference. CONCLUSIONS Exposure to fluoridated water implied lower mean values for the DMFT and SiC indexes, even in the presence of the concomitant exposure to fluoridated toothpaste, in a scenario of low prevalence of the disease, and with a similar pattern of caries distribution in the populations analyzed. PMID:29641653

Water-resources data index for Osceola National Forest, Florida

USGS Publications Warehouse

Seaber, Paul R.; Hull, Robert W.

1979-01-01

The U.S. Geological Survey conducted an intensive investigation from December 1975 to December 1977 of the geohydrology of Osceola National Forest, Fla. The primary purpose was to provide the geohydrological understanding needed to predict the impact of potential phosphate industry operations in the forest on the natural hydrologic system. The investigation involved test drilling, implementation of a hydrologic monitoring network, water-quality sampling, comprehensive aquifer tests, and literature study. This report is an index to the type, source, location, and availability of the data used in the interpretive investigation. The indexes include: geological, geophysical, ground water, surface water, quality of water, meteorological, climatological, aquifer tests, maps, photographs, elevations, and reference publications. The manner of storage and retrieval of the data is decribed also. (Woodard-USGS).

Performance of pond-wetland complexes as a preliminary processor of drinking water sources.

PubMed

Wang, Weidong; Zheng, Jun; Wang, Zhongqiong; Zhang, Rongbin; Chen, Qinghua; Yu, Xinfeng; Yin, Chengqing

2016-01-01

Shijiuyang Constructed Wetland (110 hm(2)) is a drinking water source treatment wetland with primary structural units of ponds and plant-bed/ditch systems. The wetland can process about 250,000 tonnes of source water in the Xincheng River every day and supplies raw water for Shijiuyang Drinking Water Plant. Daily data for 28 months indicated that the major water quality indexes of source water had been improved by one grade. The percentage increase for dissolved oxygen and the removal rates of ammonia nitrogen, iron and manganese were 73.63%, 38.86%, 35.64%, and 22.14% respectively. The treatment performance weight of ponds and plant-bed/ditch systems was roughly equal but they treated different pollutants preferentially. Most water quality indexes had better treatment efficacy with increasing temperature and inlet concentrations. These results revealed that the pond-wetland complexes exhibited strong buffering capacity for source water quality improvement. The treatment cost of Shijiuyang Drinking Water Plant was reduced by about 30.3%. Regional rainfall significantly determined the external river water levels and adversely deteriorated the inlet water quality, thus suggesting that the "hidden" diffuse pollution in the multitudinous stream branches as well as their catchments should be the controlling emphases for river source water protection in the future. The combination of pond and plant-bed/ditch systems provides a successful paradigm for drinking water source pretreatment. Three other drinking water source treatment wetlands with ponds and plant-bed/ditch systems are in operation or construction in the stream networks of the Yangtze River Delta and more people will be benefited. Copyright © 2015. Published by Elsevier B.V.

Estimate of the Impact of Absorbing Aerosol Over Cloud on the MODIS Retrievals of Cloud Optical Thickness and Effective Radius Using Two Independent Retrievals of Liquid Water Path

NASA Technical Reports Server (NTRS)

Wilcox, Eric M.; Harshvardhan; Platnick, Steven

2009-01-01

Two independent satellite retrievals of cloud liquid water path (LWP) from the NASA Aqua satellite are used to diagnose the impact of absorbing biomass burning aerosol overlaying boundary-layer marine water clouds on the Moderate Resolution Imaging Spectrometer (MODIS) retrievals of cloud optical thickness (tau) and cloud droplet effective radius (r(sub e)). In the MODIS retrieval over oceans, cloud reflectance in the 0.86-micrometer and 2.13-micrometer bands is used to simultaneously retrieve tau and r(sub e). A low bias in the MODIS tau retrieval may result from reductions in the 0.86-micrometer reflectance, which is only very weakly absorbed by clouds, owing to absorption by aerosols in cases where biomass burning aerosols occur above water clouds. MODIS LWP, derived from the product of the retrieved tau and r(sub e), is compared with LWP ocean retrievals from the Advanced Microwave Scanning Radiometer-EOS (AMSR-E), determined from cloud microwave emission that is transparent to aerosols. For the coastal Atlantic southern African region investigated in this study, a systematic difference between AMSR-E and MODIS LWP retrievals is found for stratocumulus clouds over three biomass burning months in 2005 and 2006 that is consistent with above-cloud absorbing aerosols. Biomass burning aerosol is detected using the ultraviolet aerosol index from the Ozone Monitoring Instrument (OMI) on the Aura satellite. The LWP difference (AMSR-E minus MODIS) increases both with increasing tau and increasing OMI aerosol index. During the biomass burning season the mean LWP difference is 14 g per square meters, which is within the 15-20 g per square meter range of estimated uncertainties in instantaneous LWP retrievals. For samples with only low amounts of overlaying smoke (OMI AI less than or equal to 1) the difference is 9.4, suggesting that the impact of smoke aerosols on the mean MODIS LWP is 5.6 g per square meter. Only for scenes with OMI aerosol index greater than 2 does the average LWP difference and the estimated bias in MODIS cloud optical thickness attributable to the impact of overlaying biomass burning aerosol exceed the instantaneous uncertainty in the retrievals.

Evaluation of water quality and stability in the drinking water distribution network in the Azogues city, Ecuador.

PubMed

García-Ávila, Fernando; Ramos-Fernández, Lía; Pauta, Damián; Quezada, Diego

2018-06-01

This document presents the physical-chemical parameters with the objective of evaluating and analyzing the drinking water quality in the Azogues city applying the water quality index (WQI) and to research the water stability in the distribution network using corrosion indexes. Thirty samples were collected monthly for six months throughout the drinking water distribution network; turbidity, temperature, electric conductivity, pH, total dissolved solids, total hardness, calcium, magnesium, alkalinity, chlorides, nitrates, sulfates and phosphates were determined; the physical-chemical parameters were measured using standard methods. The processed data revealed that the average values ​​of LSI, RSI and PSI were 0.5 (±0.34), 6.76 (±0.6), 6.50 (±0.99) respectively. The WQI calculation indicated that 100% of the samples are considered excellent quality water. According to the Langelier, Ryznar and Pukorius indexes showed that drinking water in Azogues is corrosive. The quality of drinking water according to the WQI is in a good and excellent category.

Analysis of water sorption isotherms of amorphous food materials by solution thermodynamics with relevance to glass transition: evaluation of plasticizing effect of water by the thermodynamic parameters.

PubMed

Shimazaki, Eriko; Tashiro, Akiko; Kumagai, Hitomi; Kumagai, Hitoshi

2017-04-01

Relation between the thermodynamic parameters obtained from water sorption isotherms and the degree of reduction in the glass transition temperature (T g ), accompanied by water sorption, was quantitatively studied. Two well-known glassy food materials namely, wheat gluten and maltodextrin were used as samples. The difference between the chemical potential of water in a solution and that of pure water ([Formula: see text]), the difference between the chemical potential of solid in a solution and that of a pure solid ([Formula: see text]), and the change in the integral Gibbs free energy ([Formula: see text]) were obtained by analyzing the water sorption isotherms using solution thermodynamics. The parameter [Formula: see text] correlated well with ΔT g (≡T g  - T g0 ; where T g0 is the glass transition temperature of dry material), which had been taken to be an index of plasticizing effect. This indicates that plasticizing effect of water on foods can be evaluated through the parameter [Formula: see text].

[Concentrations and pollution assessment of soil heavy metals at different water-level altitudes in the draw-down areas of the Three Gorges Reservoir].

PubMed

Wang, Ye-Chun; Lei, Bo; Yang, San-Ming; Zhang, Sheng

2012-02-01

To investigate the effect of 175 m trial impounding (2008 and 2009) of the Three Gorges Reservoir on soil heavy metals, three draw-down areas with similar geological environment and history of land-use in Zhongxian County were chosen. Altogether 36 surface soil samples (including 0-10 cm and 10-20 cm soil layer) from water-level altitude of 160 m and 170 m were obtained, and their heavy metals concentrations (As, Cd, Cr, Cu, Ni, Pb and Zn) were measured by the X-ray fluorescence spectrometric method. Geoaccumulation index (I(geo)) and Håkanson potential ecological risk index were applied to assess the heavy metals pollution status and potential ecological risk, respectively. Results indicated that although the inundation period of 160 m was 224 d longer than that of 170 m, significant difference in concentrations of heavy metals were not found between the two water-level altitudes. Except for Cd, most of the heavy metals highly related with each other positively. According to the geoaccumulation index, the pollution extent of the heavy metals followed the order: As > Cd > Cu > Ni > Zn = Pb > Cr. The I(geo) value of As, Cd and Cu were 0.45, 0.39 and 0.06, respectively, indicating that the soil was only lightly polluted by these heavy metals. Håkanson single potential ecological risk index followed the order: Cd > As > Cu > Pb > Ni > Cr > Zn. Cd with E(i) values of 59.10, had a medium potential for ecological risk,while As, Cr, Cu, Pb, Ni and Zn only had a light potential. Consequently, although As, Cd and Cu were the major heavy metals with potential ecological risk for surface soil pollution in the draw-down areas in Zhongxian County, the Three Gorges Reservoir.

Effect of ecological group classification schemes on performance of the AMBI benthic index in US coastal waters

EPA Science Inventory

The AZTI Marine Biotic Index (AMBI) requires less geographically-specific calibration than other benthic indices, but has not performed as well in US coastal waters as it has in the European waters for which it was originally developed. Here we examine the extent of improvement i...

Ecohydrological optimality in the Northeast China Transect

NASA Astrophysics Data System (ADS)

Cong, Zhentao; Li, Qinshu; Mo, Kangle; Zhang, Lexin; Shen, Hong

2017-05-01

The Northeast China Transect (NECT) is one of the International Geosphere-Biosphere Program (IGBP) terrestrial transects, where there is a significant precipitation gradient from east to west, as well as a vegetation transition of forest-grassland-desert. It is remarkable to understand vegetation distribution and dynamics under climate change in this transect. We take canopy cover (M), derived from Normalized Difference Vegetation Index (NDVI), as an index to describe the properties of vegetation distribution and dynamics in the NECT. In Eagleson's ecohydrological optimality theory, the optimal canopy cover (M*) is determined by the trade-off between water supply depending on water balance and water demand depending on canopy transpiration. We apply Eagleson's ecohydrological optimality method in the NECT based on data from 2000 to 2013 to get M*, which is compared with M from NDVI to further discuss the sensitivity of M* to vegetation properties and climate factors. The result indicates that the average M* fits the actual M well (for forest, M* = 0.822 while M = 0.826; for grassland, M* = 0.353 while M = 0.352; the correlation coefficient between M and M* is 0.81). Results of water balance also match the field-measured data in the references. The sensitivity analyses show that M* decreases with the increase of leaf area index (LAI), stem fraction and temperature, while it increases with the increase of leaf angle and precipitation amount. Eagleson's ecohydrological optimality method offers a quantitative way to understand the impacts of climate change on canopy cover and provides guidelines for ecorestoration projects.

Developing a chloramine decay index to understand nitrification: A case study of two chloraminated drinking water distribution systems.

PubMed

Moradi, Sina; Liu, Sanly; Chow, Christopher W K; van Leeuwen, John; Cook, David; Drikas, Mary; Amal, Rose

2017-07-01

The management of chloramine decay and the prevention of nitrification are some of the critical issues faced by water utilities that use chloramine as a disinfectant. In this study, potential association between high performance size exclusion chromatography (HPSEC) data obtained with multiple wavelength Ultraviolet (UV) detection from two drinking water distribution systems in Australia and nitrification occurrence was investigated. An increase in the absorbance signal of HPSEC profiles with UV detection at λ=230nm between apparent molecular weights of 200 to 1000Da was observed at sampling sites that experienced rapid chloramine decay and nitrification while its absorbance signal at λ=254nm decreased. A chloramine decay index (C.D.I) defined as the ratio of area beneath the HPSEC spectra at two different wavelengths of 230 and 254nm, was used in assessing chloramine decay occurrences. The C.D.Is of waters at locations that experienced nitrification were consistently higher than locations not experiencing nitrification. A simulated laboratory study showed that the formation of nitrite/nitrate and/or soluble microbial products and/or the release of extracellular polymeric substances (EPS) during nitrification may contribute to the C.D.I. increase. These findings suggest that C.D.I derived from HPSEC with multiple wavelength UV detection could be an informative index to track the occurrence of rapid chloramine decay and nitrification. Copyright © 2016. Published by Elsevier B.V.

Comparison of macroinvertebrate-derived stream quality metrics between snag and riffle habitats

USGS Publications Warehouse

Stepenuck, K.F.; Crunkilton, R.L.; Bozek, Michael A.; Wang, L.

2008-01-01

We compared benthic macroinvertebrate assemblage structure at snag and riffle habitats in 43 Wisconsin streams across a range of watershed urbanization using a variety of stream quality metrics. Discriminant analysis indicated that dominant taxa at riffles and snags differed; Hydropsychid caddisflies (Hydropsyche betteni and Cheumatopsyche spp.) and elmid beetles (Optioservus spp. and Stenemlis spp.) typified riffles, whereas isopods (Asellus intermedius) and amphipods (Hyalella azteca and Gammarus pseudolimnaeus) predominated in snags. Analysis of covariance indicated that samples from snag and riffle habitats differed significantly in their response to the urbanization gradient for the Hilsenhoff biotic index (BI), Shannon's diversity index, and percent of filterers, shredders, and pollution intolerant Ephemeroptera, Plecoptera, and Trichoptera (EPT) at each stream site (p ??? 0.10). These differences suggest that although macroinvertebrate assemblages present in either habitat type are sensitive to detecting the effects of urbanization, metrics derived from different habitats should not be intermixed when assessing stream quality through biomonitoring. This can be a limitation to resource managers who wish to compare water quality among streams where the same habitat type is not available at all stream locations, or where a specific habitat type (i.e., a riffle) is required to determine a metric value (i.e., BI). To account for differences in stream quality at sites lacking riffle habitat, snag-derived metric values can be adjusted based on those obtained from riffles that have been exposed to the same level of urbanization. Comparison of nonlinear regression equations that related stream quality metric values from the two habitat types to percent watershed urbanization indicated that snag habitats had on average 30.2 fewer percent EPT individuals, a lower diversity index value than riffles, and a BI value of 0.29 greater than riffles. ?? 2008 American Water Resources Association.

A minimalist probabilistic description of root zone soil water

USGS Publications Warehouse

Milly, P.C.D.

2001-01-01

The probabilistic response of depth‐integrated soil water to given climatic forcing can be described readily using an existing supply‐demand‐storage model. An apparently complex interaction of numerous soil, climate, and plant controls can be reduced to a relatively simple expression for the equilibrium probability density function of soil water as a function of only two dimensionless parameters. These are the index of dryness (ratio of mean potential evaporation to mean precipitation) and a dimensionless storage capacity (active root zone soil water capacity divided by mean storm depth). The first parameter is mainly controlled by climate, with surface albedo playing a subsidiary role in determining net radiation. The second is a composite of soil (through moisture retention characteristics), vegetation (through rooting characteristics), and climate (mean storm depth). This minimalist analysis captures many essential features of a more general probabilistic analysis, but with a considerable reduction in complexity and consequent elucidation of the critical controls on soil water variability. In particular, it is shown that (1) the dependence of mean soil water on the index of dryness approaches a step function in the limit of large soil water capacity; (2) soil water variance is usually maximized when the index of dryness equals 1, and the width of the peak varies inversely with dimensionless storage capacity; (3) soil water has a uniform probability density function when the index of dryness is 1 and the dimensionless storage capacity is large; and (4) the soil water probability density function is bimodal if and only if the index of dryness is <1, but this bimodality is pronounced only for artificially small values of the dimensionless storage capacity.

Spatio-temporal evaluation of Yamchi Dam basin water quality using Canadian water quality index.

PubMed

Farzadkia, Mahdi; Djahed, Babak; Shahsavani, Esmaeel; Poureshg, Yousef

2015-04-01

In recent years, the growth of population and increase of the industries around the tributaries of Yamchi Dam basin have led to deterioration of dam water quality. This study aimed to evaluate the quality of the Yamchi Dam basin water, which is used for drinking and irrigation consumptions using Canadian Water Quality Index (CWQI) model, and to determine the main water pollution sources of this basin. Initially, nine sampling stations were selected in the sensitive locations of the mentioned basin's tributaries, and 12 physico-chemical parameters and 2 biological parameters were measured. The CWQI for drinking consumptions was under 40 at all the stations indicating a poor water quality for drinking consumptions. On the other hand, the CWQI was 62-100 for irrigation at different stations; thus, the water had an excellent to fair quality for irrigation consumptions. Almost in all the stations, the quality of irrigation and drinking water in cold season was better. Besides, for drinking use, total coliform and fecal coliform had the highest frequency of failure, and total coliform had the maximum deviation from the specified objective. For irrigation use, total suspended solids had the highest frequency of failure and deviation from the objective in most of the stations. The pisciculture center, aquaculture center, and the Nir City wastewater discharge were determined as the main pollution sources of the Yamchi Dam basin. Therefore, to improve the water quality in this important surface water resource, urban and industrial wastewater treatment prior to disposal and more stringent environmental legislations are recommended.

Assessing the risks of trace elements in environmental materials under selected greenhouse vegetable production systems of China.

PubMed

Chen, Yong; Huang, Biao; Hu, Wenyou; Weindorf, David C; Liu, Xiaoxiao; Niedermann, Silvana

2014-02-01

The risk assessment of trace elements of different environmental media in conventional and organic greenhouse vegetable production systems (CGVPS and OGVPS) can reveal the influence of different farming philosophy on the trace element accumulations and their effects on human health. These provide important basic data for the environmental protection and human health. This paper presents trace element accumulation characteristics of different land uses; reveals the difference of soil trace element accumulation both with and without consideration of background levels; compares the trace element uptake by main vegetables; and assesses the trace element risks of soils, vegetables, waters and agricultural inputs, using two selected greenhouse vegetable systems in Nanjing, China as examples. Results showed that greenhouse vegetable fields contained significant accumulations of Zn in CGVPS relative to rice-wheat rotation fields, open vegetable fields, and geochemical background levels, and this was the case for organic matter in OGVPS. The comparative analysis of the soil medium in two systems with consideration of geochemical background levels and evaluation of the geo-accumulation pollution index achieved a more reasonable comparison and accurate assessment relative to the direct comparison analysis and the evaluation of the Nemerow pollution index, respectively. According to the Chinese food safety standards and the value of the target hazard quotient or hazard index, trace element contents of vegetables were safe for local residents in both systems. However, the spatial distribution of the estimated hazard index for producers still presented certain specific hotspots which may cause potential risk for human health in CGVPS. The water was mainly influenced by nitrogen, especially for CGVPS, while the potential risk of Cd and Cu pollution came from sediments in OGVPS. The main inputs for trace elements were fertilizers which were relatively safe based on relevant standards; but excess application caused trace element accumulations in the environmental media. Copyright © 2013 Elsevier B.V. All rights reserved.

Within-catchment variation in regulation of water use by eucalypts, and the roles of stomatal anatomy and physiology

NASA Astrophysics Data System (ADS)

Gharun, Mana; Turnbull, Tarryn; Adams, Mark

2014-05-01

Understanding how environmental cues impact water use of forested catchments is crucial for accurate calculation of water balance and effective catchment management in terrestrial ecosystems. We characterised structural and physiological properties of leaves and canopies of Eucalyptus delegatensis, E. pauciflora and E. radiata, the most common species in high-country catchments in temperate Australia. These properties were related to whole-tree water transport to assess differences in water use strategies among the three species. Stomatal conductance, instantaneous transpiration efficiency, stomatal occlusion (through cuticular ledges) and leaf area index differed significantly among species. Whole-tree water use of all species was strongly coupled to changes in vapour pressure deficit (VPD) and photosynthetically active radiation (Q), yet stomatal closure reduced water transport at VPD > 1 kPa in all species, even when soil water was not limiting. The observed differences in leaf traits and related water use strategies reflect species-specific adaptations to dominant environmental conditions within the landscape matrix of catchments. The generalist E. radiata seems to follow an opportunistic, while the two more spatially restricted species have adopted a pessimistic water use strategy. Catchment-scale models of carbon and water fluxes will need to reflect such variation in structure and function, if they are to fully capture species effects on water balance and yield.

Assessment of Drought Severity Using Normal Precipitation Index (Case Study: Sistan and Baluchistan Province)

NASA Astrophysics Data System (ADS)

Rahimi, D.; Movahedi, S.

2009-04-01

In the last decades, water crisis is one of the most important critical phenomenons in the environment planning and human society's management which affecting on development aspects in the international, national and regional levels. In this research, have been considered the Drought as the main parameter in water rare serious. For drought assessment, can treat the different methods, such as statistical model, meteorological and hydrological methods. In this research, have been used the Normal Precipitation index to meteorological analysis of drought severity in Sistan and Baluchistan province with high drought severity during recent years. According to the obtained result, the annual precipitation of studied area was between 36 to 52 percent more than mean precipitation of province. 10%-23 percent of precipitation amount involved the drought threshold border, 3%-13 percent of precipitations contain the weakness drought, 6.7% -23 percent were considered for moderate drought, 6%-20 percent involved the severe drought and ultimately, 6.7% to 23 percent of precipitations were considered as very severe drought. Keywords: Drought, Normal index, precipitation, Sistan and Baluchistan

Study on the Water Resource Sustainable Utilization Evaluation Index System in Jiangsu Coast Reclamation Region

NASA Astrophysics Data System (ADS)

Ren, L.

2016-12-01

As a comprehensive system, there are many subsystems such as water resource subsystem, social subsystem, economic subsystem and ecological subsystem in water resource sustainable utilization system. In this paper, an evaluation system including three levels is set up according to the metric demands of sustainable water resource utilization in Jiangsu coast reclamation region, namely the target level, the rule level, and the index level. Considering the large number of the indexes, the analytic hierarchy process is used to determine the weights of all these subsystems in the total goal of water sustainable utilization. By analyzing these weights, the attributes of water resource itself is found to be the most important aspect for the evaluation of sustainable utilization in Jiangsu coast reclamation region, and the second important aspect is the situation of the eco-environment.

Comparative analysis of time-scaling properties about water pH in Poyang Lake Inlet and Outlet on the basis of fractal methods.

PubMed

Shi, K; Liu, C Q; Huang, Z W; Zhang, B; Su, Y

2010-01-01

Detrended fluctuation analysis (DFA) and multifractal methods are applied to the time-scaling properties analysis of water pH series in Poyang Lake Inlet and Outlet in China. The results show that these pH series are characterised by long-term memory and multifractal scaling, and these characteristics have obvious differences between the Lake Inlet and Outlet. The comparison results suggest that monofractal and multifractal parameters can be quantitative dynamical indexes reflecting the capability of anti-acidification of Poyang Lake. Furthermore, we investigated the frequency-size distribution of pH series in Poyang Lake Inlet and Outlet. Our findings suggest that water pH is an example of a self-organised criticality (SOC) process. The results show that it is different SOC behaviours that result in the differences of power-law relations between pH series in Poyang Lake Inlet and Outlet. This work can be helpful to improvement of modelling of lake water quality.

Effect of Nitrogen Compounds on Shrimp Litopenaeus vannamei: Histological Alterations of the Antennal Gland.

PubMed

Fregoso-López, Marcela G; Morales-Covarrubias, María S; Franco-Nava, Miguel A; Ponce-Palafox, Jesús T; Fierro-Sañudo, Juan F; Ramírez-Rochín, Javier; Páez-Osuna, Federico

2018-06-01

Two experimental modules with different stocking densities (M1 = 70 and M2 = 120 shrimp m -2 ) were examined weekly during 72-day culture cycle at low-salinity water (1.9 g L -1 ) and zero-water exchange to examine the effects of water quality deterioration on the antennal gland (AG) of shrimp. Results showed survival rates of 87.7% and 11.9% in M1 and M2, respectively. Water temperature, pH, dissolved oxygen, and chlorophyll a were not significantly different between modules but the concentrations of the nitrogen compounds were significantly different between modules with the exception of nitrite-N, showing a higher histological alteration index in M2 (32 ± 10) than M1 (22 ± 0) with a strong correlation with the nitrogen compounds. During the last weeks was evidenced in M1 inflammation and hemocytic and hemolymph infiltration, while in M2, melanization, hemocytic melanized nodules and cells with kariorrexis.

Comparison of Vegetation Indices from Rpas and SENTINEL-2 Imagery for Detecting Permanent Pastures

NASA Astrophysics Data System (ADS)

Piragnolo, M.; Lusiani, G.; Pirotti, F.

2018-04-01

Permanent pastures (PP) are defined as grasslands, which are not subjected to any tillage, but only to natural growth. They are important for local economies in the production of fodder and pastures (Ali et al. 2016). Under these definitions, a pasture is permanent when it is not under any crop-rotation, and its production is related to only irrigation, fertilization and mowing. Subsidy payments to landowners require monitoring activities to determine which sites can be considered PP. These activities are mainly done with visual field surveys by experienced personnel or lately also using remote sensing techniques. The regional agency for SPS subsidies, the Agenzia Veneta per i Pagamenti in Agricoltura (AVEPA) takes care of monitoring and control on behalf of the Veneto Region using remote sensing techniques. The investigation integrate temporal series of Sentinel-2 imagery with RPAS. Indeed, the testing area is specific region were the agricultural land is intensively cultivated for production of hay harvesting four times every year between May and October. The study goal of this study is to monitor vegetation presence and amount using the Normalized Difference Vegetation Index (NDVI), the Soil-adjusted Vegetation Index (SAVI), the Normalized Difference Water Index (NDWI), and the Normalized Difference Built Index (NDBI). The overall objective is to define for each index a set of thresholds to define if a pasture can be classified as PP or not and recognize the mowing.

Mobility Analyses of Standard- and High-Mobility Tactical Support Vehicles (HIMO Study)

DTIC Science & Technology

1976-02-01

l, APPENDIX G: PARTICIPANTS IN SCENARIO EXERCISES ... ....... Gl I ?S LIST OF TABLES Table Page I Summary of Vehicle Caracteristics and Some...15 1 :1010 2 :1111 Organid silts and clays ( plastic ) >7-30 0 11212 1 1 1313Peat (nou plastic ) _._>_3_0 0 .1414 Li Groups with Different Materiai in 0...diameter LL = Liquid limit PI - Plasticity index Drainage potential classified by occurrence of water table as follows: Class 0 Water table occurs at

Effects of Source- versus Household Contamination of Tubewell Water on Child Diarrhea in Rural Bangladesh: A Randomized Controlled Trial

PubMed Central

Unicomb, Leanne; Arnold, Benjamin F.; Colford Jr., John M.; Luby, Stephen P.

2015-01-01

Background Shallow tubewells are the primary drinking water source for most rural Bangladeshis. Fecal contamination has been detected in tubewells, at low concentrations at the source and at higher levels at the point of use. We conducted a randomized controlled trial to assess whether improving the microbiological quality of tubewell drinking water by household water treatment and safe storage would reduce diarrhea in children <2 years in rural Bangladesh. Methods We randomly assigned 1800 households with a child aged 6-18 months (index child) into one of three arms: chlorine plus safe storage, safe storage and control. We followed households with monthly visits for one year to promote the interventions, track their uptake, test participants’ source and stored water for fecal contamination, and record caregiver-reported child diarrhea prevalence (primary outcome). To assess reporting bias, we also collected data on health outcomes that are not expected to be impacted by our interventions. Findings Both interventions had high uptake. Safe storage, alone or combined with chlorination, reduced heavy contamination of stored water. Compared to controls, diarrhea in index children was reduced by 36% in the chlorine plus safe storage arm (prevalence ratio, PR = 0.64, 0.55-0.73) and 31% in the safe storage arm (PR = 0.69, 0.60-0.80), with no difference between the two intervention arms. One limitation of the study was the non-blinded design with self-reported outcomes. However, the prevalence of health outcomes not expected to be impacted by water interventions did not differ between study arms, suggesting minimal reporting bias. Conclusions Safe storage significantly improved drinking water quality at the point of use and reduced child diarrhea in rural Bangladesh. There was no added benefit from combining safe storage with chlorination. Efforts should be undertaken to implement and evaluate long-term efforts for safe water storage in Bangladesh. Trial Registration ClinicalTrials.gov NCT01350063 PMID:25816342

[Influence of Different Straws Returning with Landfill on Soil Microbial Community Structure Under Dry and Water Farming].

PubMed

Lan, Mu-ling; Gao, Ming

2015-11-01

Based on rice, wheat, corn straw and rape, broad bean green stalk as the research object, using phospholipid fatty acid (PLFA) method, combining principal component analysis method to study the soil microbial quantity, distribution of flora, community structure characteristics under dry and water farming as two different cultivated land use types. The PLFA analysis results showed that: under dry farming, total PLFA quantity ranged 8.35-25.15 nmol x g(-1), showed rape > broad bean > corn > rice > wheat, rape and broad bean significantly increased total PLFA quantity by 1.18 and 1.08 times compared to the treatment without straw; PLFA quantity of bacterial flora in treatments with straws was higher than that without straw, and fungal biomass was significantly increased, so was the species richness of microbial community. Under water faming, the treatments of different straws returning with landfill have improved the PLFA quantity of total soil microbial and flora comparing with the treatment without straw, fungi significantly increased, and species richness of microbial communities value also increased significantly. Total PLFA quantity ranged 4.04-22.19 nmol x g(-1), showed rice > corn > wheat > broad bean > rape, which in rape and broad bean treatments were lower than the treatment without straw; fungal PLFA amount in 5 kinds of straw except broad bean treatment was significantly higher than that of the treatment without straw, bacteria and total PLFA quantity in broad bean processing were significantly lower than those of other treatments, actinomycetes, G+, G- had no significant difference between all treatments; rice, wheat, corn, rape could significantly increase the soil microbial species richness index and dominance index under water faming. The results of principal component analysis showed that broad bean green stalk had the greatest impact on the microbial community structure in the dry soil, rape green stalk and wheat straw had the biggest influence on soil microbial community structure in water soil.

Options for refractive index and viscosity matching to study variable density flows

NASA Astrophysics Data System (ADS)

Clément, Simon A.; Guillemain, Anaïs; McCleney, Amy B.; Bardet, Philippe M.

2018-02-01

Variable density flows are often studied by mixing two miscible aqueous solutions of different densities. To perform optical diagnostics in such environments, the refractive index of the fluids must be matched, which can be achieved by carefully choosing the two solutes and the concentration of the solutions. To separate the effects of buoyancy forces and viscosity variations, it is desirable to match the viscosity of the two solutions in addition to their refractive index. In this manuscript, several pairs of index matched fluids are compared in terms of viscosity matching, monetary cost, and practical use. Two fluid pairs are studied in detail, with two aqueous solutions (binary solutions of water and a salt or alcohol) mixed into a ternary solution. In each case: an aqueous solution of isopropanol mixed with an aqueous solution of sodium chloride (NaCl) and an aqueous solution of glycerol mixed with an aqueous solution of sodium sulfate (Na_2SO_4). The first fluid pair allows reaching high-density differences at low cost, but brings a large difference in dynamic viscosity. The second allows matching dynamic viscosity and refractive index simultaneously, at reasonable cost. For each of these four solutes, the density, kinematic viscosity, and refractive index are measured versus concentration and temperature, as well as wavelength for the refractive index. To investigate non-linear effects when two index-matched, binary solutions are mixed, the ternary solutions formed are also analyzed. Results show that density and refractive index follow a linear variation with concentration. However, the viscosity of the isopropanol and NaCl pair deviates from the linear law and has to be considered. Empirical correlations and their coefficients are given to create index-matched fluids at a chosen temperature and wavelength. Finally, the effectiveness of the refractive index matching is illustrated with particle image velocimetry measurements performed for a buoyant jet in a linearly stratified environment. The creation of the index-matched solutions and linear stratification in a large-scale experimental facility are detailed, as well as the practical challenges to obtain precise refractive index matching.

Modelling the potential role of forest thinning in maintaining water supplies under a changing climate across the conterminous United States

Treesearch

Ge Sun; Peter V. Caldwell; Steven G. McNulty

2015-01-01

The goal of this study was to test the sensitivity of water yield to forest thinning and other forest management/disturbances and climate across the conterminous United States (CONUS). Leaf area index (LAI) was selected as a key parameter linking changes in forest ecosystem structure and functions. We used the Water Supply Stress Index model to examine water yield...

Southern Phosphorus Indices, Water Quality Data, and Modeling (APEX, APLE, and TBET) Results: A Comparison.

PubMed

Osmond, Deanna; Bolster, Carl; Sharpley, Andrew; Cabrera, Miguel; Feagley, Sam; Forsberg, Adam; Mitchell, Charles; Mylavarapu, Rao; Oldham, J Larry; Radcliffe, David E; Ramirez-Avila, John J; Storm, Dan E; Walker, Forbes; Zhang, Hailin

2017-11-01

Phosphorus (P) Indices in the southern United States frequently produce different recommendations for similar conditions. We compared risk ratings from 12 southern states (Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, and Texas) using data collected from benchmark sites in the South (Arkansas, Georgia, Mississippi, North Carolina, Oklahoma, and Texas). Phosphorus Index ratings were developed using both measured erosion losses from each benchmark site and Revised Universal Soil Loss Equation 2 predictions; mostly, there was no difference in P Index outcome. The derived loss ratings were then compared with measured P loads at the benchmark sites by using equivalent USDA-NRCS P Index ratings and three water quality models (Annual P Loss Estimator [APLE], Agricultural Policy Environmental eXtender [APEX], and Texas Best Management Practice Evaluation Tool [TBET]). Phosphorus indices were finally compared against each other using USDA-NRCS loss ratings model estimate correspondence with USDA-NRCS loss ratings. Correspondence was 61% for APEX, 48% for APLE, and 52% for TBET, with overall P index correspondence at 55%. Additive P Indices (Alabama and Texas) had the lowest USDA-NRCS loss rating correspondence (31%), while the multiplicative (Arkansas, Florida, Louisiana, Mississippi, South Carolina, and Tennessee) and component (Georgia, Kentucky, and North Carolina) indices had similar USDA-NRCS loss rating correspondence-60 and 64%, respectively. Analysis using Kendall's modified Tau suggested that correlations between measured and calculated P-loss ratings were similar or better for most P Indices than the models. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Spatial modeling on the upperstream of the Citarum watershed: An application of geoinformatics

NASA Astrophysics Data System (ADS)

Ningrum, Windy Setia; Widyaningsih, Yekti; Indra, Tito Latif

2017-03-01

The Citarum watershed is the longest and the largest watershed in West Java, Indonesia, located at 106°51'36''-107°51' E and 7°19'-6°24'S across 10 districts, and serves as the water supply for over 15 million people. In this area, the water criticality index is concerned to reach the balance between water supply and water demand, so that in the dry season, the watershed is still able to meet the water needs of the society along the Citarum river. The objective of this research is to evaluate the water criticality index of Citarum watershed area using spatial model to overcome the spatial dependencies in the data. The result of Lagrange multiplier diagnostics for spatial dependence results are LM-err = 34.6 (p-value = 4.1e-09) and LM-lag = 8.05 (p-value = 0.005), then modeling using Spatial Lag Model (SLM) and Spatial Error Model (SEM) were conducted. The likelihood ratio test show that both of SLM dan SEM model is better than OLS model in modeling water criticality index in Citarum watershed. The AIC value of SLM and SEM model are 78.9 and 51.4, then the SEM model is better than SLM model in predicting water criticality index in Citarum watershed.

High-resolution near real-time drought monitoring in South Asia

NASA Astrophysics Data System (ADS)

Aadhar, Saran; Mishra, Vimal

2017-10-01

Drought in South Asia affect food and water security and pose challenges for millions of people. For policy-making, planning, and management of water resources at sub-basin or administrative levels, high-resolution datasets of precipitation and air temperature are required in near-real time. We develop a high-resolution (0.05°) bias-corrected precipitation and temperature data that can be used to monitor near real-time drought conditions over South Asia. Moreover, the dataset can be used to monitor climatic extremes (heat and cold waves, dry and wet anomalies) in South Asia. A distribution mapping method was applied to correct bias in precipitation and air temperature, which performed well compared to the other bias correction method based on linear scaling. Bias-corrected precipitation and temperature data were used to estimate Standardized precipitation index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) to assess the historical and current drought conditions in South Asia. We evaluated drought severity and extent against the satellite-based Normalized Difference Vegetation Index (NDVI) anomalies and satellite-driven Drought Severity Index (DSI) at 0.05°. The bias-corrected high-resolution data can effectively capture observed drought conditions as shown by the satellite-based drought estimates. High resolution near real-time dataset can provide valuable information for decision-making at district and sub-basin levels.

Determining the refractive index of particles using glare-point imaging technique

NASA Astrophysics Data System (ADS)

Meng, Rui; Ge, Baozhen; Lu, Qieni; Yu, Xiaoxue

2018-04-01

A method of measuring the refractive index of a particle is presented from a glare-point image. The space of a doublet image of a particle can be determined with high accuracy by using auto-correlation and Gaussian interpolation, and then the refractive index is obtained from glare-point separation, and a factor that may influence the accuracy of glare-point separation is explored. Experiments are carried out for three different kinds of particles, including polystyrene latex particles, glass beads, and water droplets, whose measuring accuracy is improved by the data fitting method. The research results show that the method presented in this paper is feasible and beneficial to applications such as spray and atmospheric composition measurements.

Alisiaquinones and alisiaquinol, dual inhibitors of Plasmodium falciparum enzyme targets from a New Caledonian deep water sponge.

PubMed

Desoubzdanne, Denis; Marcourt, Laurence; Raux, Roselyne; Chevalley, Séverine; Dorin, Dominique; Doerig, Christian; Valentin, Alexis; Ausseil, Frédéric; Debitus, Cécile

2008-07-01

Four new meroterpenes, alisiaquinones A-C (1-3) and alisiaquinol (4), were isolated from a New Caledonian deep water sponge. Their structures and relative stereochemistry were elucidated by spectroscopic data analysis. They are related to xestoquinone, but showed unusual substitution on a tetrahydrofuran junction. They displayed micromolar range activity on two enzymatic targets of importance for the control of malaria, the plasmodial kinase Pfnek-1 and a protein farnesyl transferase, as well as on different chloroquine-sensitive and -resistant strains of Plasmodium falciparum. Alisiaquinone C displayed a submicromolar activity on P. falciparum and a competitive selectivity index on the different plasmodial strains.

Climate, interseasonal storage of soil water, and the annual water balance

USGS Publications Warehouse

Milly, P.C.D.

1994-01-01

The effects of annual totals and seasonal variations of precipitation and potential evaporation on the annual water balance are explored. It is assumed that the only other factor of significance to annual water balance is a simple process of water storage, and that the relevant storage capacity is the plant-available water-holding capacity of the soil. Under the assumption that precipitation and potential evaporation vary sinusoidally through the year, it is possible to derive an analytic solution of the storage problem, and this yields an expression for the fraction of precipitation that evaporates (and the fraction that runs off) as a function of three dimensionless numbers: the ratio of annual potential evaporation to annual precipitation (index of dryness); an index of the seasonality of the difference between precipitation and potential evaporation; and the ratio of plant-available water-holding capacity to annual precipitation. The solution is applied to the area of the United States east of 105??W, using published information on precipitation, potential evaporation, and plant-available water-holding capacity as inputs, and using an independent analysis of observed river runoff for model evaluation. The model generates an areal mean annual runoff of only 187 mm, which is about 30% less than the observed runoff (263 mm). The discrepancy is suggestive of the importance of runoff-generating mechanisms neglected in the model. These include intraseasonal variability (storminess) of precipitation, spatial variability of storage capacity, and finite infiltration capacity of land. ?? 1994.

Comprehensive benefit analysis of regional water resources based on multi-objective evaluation

NASA Astrophysics Data System (ADS)

Chi, Yixia; Xue, Lianqing; Zhang, Hui

2018-01-01

The purpose of the water resources comprehensive benefits analysis is to maximize the comprehensive benefits on the aspects of social, economic and ecological environment. Aiming at the defects of the traditional analytic hierarchy process in the evaluation of water resources, it proposed a comprehensive benefit evaluation of social, economic and environmental benefits index from the perspective of water resources comprehensive benefit in the social system, economic system and environmental system; determined the index weight by the improved fuzzy analytic hierarchy process (AHP), calculated the relative index of water resources comprehensive benefit and analyzed the comprehensive benefit of water resources in Xiangshui County by the multi-objective evaluation model. Based on the water resources data in Xiangshui County, 20 main comprehensive benefit assessment factors of 5 districts belonged to Xiangshui County were evaluated. The results showed that the comprehensive benefit of Xiangshui County was 0.7317, meanwhile the social economy has a further development space in the current situation of water resources.

Primary production processes in ice-free waters of the Ross Sea (Antarctica) during the austral summer 1996

NASA Astrophysics Data System (ADS)

Saggiomo, Vincenzo; Catalano, Giulio; Mangoni, Olga; Budillon, Giorgio; Carrada, Gian Carlo

During austral summer 1996 (January 11-February 10) oceanographic studies were conducted in the ice-free waters of the Ross Sea within the framework of the Italian National Programme for Antarctic Research (PNRA). Thirty-eight hydrological stations within 72.5°-78.0°S and 164.5°E-175.0°W were sampled. Size-fractionated photosynthetic pigments were measured at all stations, primary production was evaluated at 24 stations, and P vs. E measurements were carried out at 3 or 4 depths at 18 stations. In the open Ross Sea, integrated chlorophyll a (Chl a) concentrations were between 15 and 102 mg m -2 in the 0-100 m layer, and primary production was between 124 and 638 mgC m -2 d -1. Offshore waters were completely ice-free and the water column was only slightly stratified. However, phytoplankton biomass and production were relatively high wherever the Upper Mixed Layer (UML) was <30 m deep. Hydrographic characters and phytoplankton distribution varied remarkably along the coastal waters of Terra Nova Bay; during a late summer bloom, integrated primary production ranged between 620 and 2411 mgC m -2 d -1. The dimensional composition of phytoplankton communities and the Redfield ratio indicate that the Ross Sea was dominated by diatoms. The photosynthetic parameters measured suggest the importance of the depth and dynamics of the UML, where the integrated mean irradiance always exceeded the photosaturation index ( Ek). However, occasionally different PmaxB and Ek were recorded even in apparently well-mixed water columns. The presence of turbulent cells in different layers of the photic zone or a weak wind-driven vertical mixing, which might induce different photosynthetic indexes, can thus be hypothesized. Simulated in situ primary production was well correlated with production calculated with the photosynthetic coefficients obtained from the P vs. E experiments. Our data could be used to construct models aimed at assessing primary production in the area studied.

Experimental analysis of the impact of sluice regulation on water quality in the highly polluted Huai River Basin, China.

PubMed

Zuo, Qiting; Chen, Hao; Dou, Ming; Zhang, Yongyong; Li, Dongfeng

2015-07-01

Impact assessment of sluice regulation on water quality is one of the crucial tasks in the present river management. However, research difficulties remain because of insufficient in situ data and numerous influencing factors in aquatic environments. The Huaidian Sluice, the main control sluice of the Shaying River, China, was selected for this study. Three field experimental programs were designed and carried out to analyze spatial and temporal variations in water quality parameters under various sluice regulation conditions and to explore the impacts of regulation mechanisms on water quality. Monitoring data were used to simulate water quality under different scenarios by the water quality analysis simulation program (WASP). Results demonstrate that the influences of sluice regulation on permanganate index (CODMn) and ammonia nitrogen (NH4-N) concentrations (indicators of water quality) were complex and nonlinear and presented different trends of increase or decrease from different regulation modes. Gate openings of different widths and different flow rates affected CODMn and NH4-N concentrations differently. Monitoring results and numerical simulation results indicate that the sluice opening should be small. Flow discharge through the sluice should be greater than 10 m(3) s and less than 60 m(3) s to maintain low CODMn concentrations, and discharge should be low (e.g., 14 m(3) s) to maintain low NH4-N concentrations. This research provides an experimental basis for further research on the construction of water quality models and for the development of reasonable regulations on water quality and quantity.

Microbial Community Analysis in the Roots of Aquatic Plants and Isolation of Novel Microbes Including an Organism of the Candidate Phylum OP10

PubMed Central

Tanaka, Yasuhiro; Tamaki, Hideyuki; Matsuzawa, Hiroaki; Nigaya, Masahiro; Mori, Kazuhiro; Kamagata, Yoichi

2012-01-01

A number of molecular ecological studies have revealed complex and unique microbial communities in various terrestrial plant roots; however, little is known about the microbial communities of aquatic plant roots in spite of their potential use for water quality improvement in aquatic environments (e.g. floating treatment wetland system). Here, we report the microbial communities inhabiting the roots of emerged plants, reed (Phragmites australis) and Japanese loosestrife (Lythrum anceps), collected from a floating treatment wetland in a pond by both culture-independent and culture-dependent approaches. Culture-independent analysis based on 16S rRNA gene sequences revealed that the microbial compositions between the two aquatic plant roots were clearly different (e.g. the predominant microbe was Betaproteobacteria for reed and Alphaproteobacteria for Japanese loosestrife). In comparisons of microbial communities between the plant roots and pond water taken from near the plants, the microbial diversity in the plant roots (e.g. 4.40–4.26 Shannon-Weiner index) were higher than that of pond water (e.g. 3.15 Shannon-Weiner index). Furthermore, the plant roots harbored 2.5–3.5 times more phylogenetically novel clone phylotypes than pond water. The culture-dependent approach also revealed differences in the microbial composition and diversity among the two plant roots and pond water. More importantly, compared to pond water, we succeeded in isolating approximately two times more novel isolate phylotypes, including a bacterium of candidate phylum OP10 (recently named Armatimonadetes) from the plant roots. These findings suggest that aquatic plants roots are significant sources for a variety of novel organisms. PMID:22791047

Neuro-fuzzy inference system Prediction of stability indices and Sodium absorption ratio in Lordegan rural drinking water resources in west Iran.

PubMed

Takdastan, Afshin; Mirzabeygi Radfard, Majid; Yousefi, Mahmood; Abbasnia, Abbas; Khodadadia, Rouhollah; Soleimani, Hamed; Mahvi, Amir Hossein; Naghan, Davood Jalili

2018-06-01

According to World Health Organization guidelines, corrosion control is an important aspect of safe drinking-water supplies. Water always includes ingredients, dissolved gases and suspended materials. Although some of these water ingredients is indispensable for human beings, these elements more than permissible limits, could be endanger human health. The aim of this study is to assess physical and chemical parameters of drinking water in the rural areas of Lordegan city, also to determine corrosion indices. This cross-sectional study has carried out with 141 taken samples during 2017 with 13 parameters, which has been analyzed based on standard method and to estimate the water quality indices from groundwater using ANFIS. Also with regard to standard conditions, results of this paper are compared with Environmental Protection Agency and Iran national standards. Five indices, Ryznar Stability Index (RSI), Langlier Saturation Index (LSI), Larson-Skold Index (LS), Puckorius Scaling Index (PSI), and Aggressive Index (AI) programmed by using Microsoft Excel software. Owing to its simplicity, the program, can easily be used by researchers and operators. Parameters included Sulfate, Sodium, Chloride, and Electrical Conductivity respectively were 13.5, 28, 10.5, and 15% more than standard level. The amount of Nitrate, in 98% of cases were in permissible limits and about 2% were more than standard level. Result of presented research indicate that water is corrosive at 10.6%,89.4%,87.2%,59.6% and 14.9% of drinking water supply reservoirs, according to LSI, RSI, PSI, LS and AI, respectively.

The effectiveness of a magnetized water oral irrigator (Hydro Floss) on plaque, calculus and gingival health.

PubMed

Johnson, K E; Sanders, J J; Gellin, R G; Palesch, Y Y

1998-04-01

The purpose of this study was to evaluate the effects of a magnetized water oral irrigator on plaque, calculus and gingival health. 29 patients completed this double-blind crossover study. Each patient was brought to baseline via an oral prophylaxis with a plaque index < or = 1 and a gingival index < or = 1. Subjects used the irrigator for a period of 3 months with the magnet and 3 months without the magnet. After each 3 month interval, data were collected using the plaque index, gingival index, and accretions index. The repeated measures analysis on plaque, gingival and calculus indices yielded a statistically-significant period effect for PlI (p=0.0343), GI (p=0.0091), and approached significance for calculus (p=0.0593). This meant that the effect of irrigation resulted in a decrease of all indices over time. Therefore, the treatment effect on each index was evaluated using only the measurements obtained at the end of the first period (i.e., assuming a parallel design). Irrigation with magnetized water resulted in 64% less calculus compared to the control group. The reduction was statistically significant (p< or =0.02). The reduction by 27% in gingival index was not statistically significant. The reduction in plaque was minimal (2.2%). A strong positive correlation between the plaque index and the Watt accretion index was observed. The magnetized water oral irrigator could be a useful adjunct in the prevention of calculus accumulation in periodontal patients, but appears to have minimal effect on plaque reduction. The results indicated a clinical improvement in the gingival index, but this was not a statistically significant finding.

Surrogate immiscible liquid pairs with refractive indexes matchable over a wide range of density and viscosity ratios

NASA Astrophysics Data System (ADS)

Saksena, Rajat; Christensen, Kenneth T.; Pearlstein, Arne J.

2015-08-01

In liquid-liquid flows, use of optical diagnostics is limited by interphase refractive index mismatch, which leads to optical distortion and complicates data interpretation, and sometimes also by opacity. Both problems can be eliminated using a surrogate pair of immiscible index-matched transparent liquids, whose density and viscosity ratios match corresponding ratios for the original liquid pair. We show that a wide range of density and viscosity ratios is accessible using aqueous solutions of 1,2-propanediol and CsBr (for which index, density, and viscosity are available), and solutions of light and heavy silicone oils and 1-bromooctane (for which we measured the same properties at 119 compositions). For each liquid phase, polynomials in the composition variables, least-squares fitted to index and density and to the logarithm of kinematic viscosity, were used to determine accessible density and viscosity ratios for each matchable index. Index-matched solution pairs can be prepared with density and viscosity ratios equal to those for water-liquid CO2 at 0 °C over a range of pressure (allowing water-liquid CO2 behavior at inconveniently high pressure to be simulated by 1-bar experiments), and for water-crude oil and water-trichloroethylene (avoiding opacity and toxicity problems, respectively), each over a range of temperature. For representative index-matched solutions, equilibration changes index, density, and viscosity only slightly, and mass spectrometry and elemental analysis show that no component of either phase has significant interphase solubility. Finally, procedures are described for iteratively reducing the residual index mismatch in surrogate solution pairs prepared on the basis of approximate polynomial fits to experimental data, and for systematically dealing with nonzero interphase solubility.

[Dental caries and fluorosis in children consuming water with different fluoride concentrations in Maiquetia, Vargas State, Venezuela].

PubMed

Montero, Maglynert; Rojas-Sanchez, Fátima; Socorro, Mairobys; Torres, José; Acevedo, Ana María

2007-03-01

The objective of this study was to determine the experience of fluorosis and dental caries in 8- 12 year old children that drink water with different fluoride concentrations, from Maiquetía, Vargas State. Four hundred and twenty-one children were evaluated and divided in groups of 84 children each, according with their age (8-9-10-11) but 85 for the age 12. This evaluation was developed by a calibrated dentist using Dean's Index for dental fluorosis examining only the six upper anterior teeth and DMFT/dmft index to determine dental caries, following the criteria established by the WHO. In addition, a social status questionnaire was given to the subjects and samples of water and salt from the communities were collected. Thirty-three per cent of the children in this study were males and 67% were females. Results indicated that the mean DMFT and dmft were 0.91 and 1.88, respectively, showing a total of 2.17 teeth with dental caries being the decayed component, the highest component observed in both dentitions. The mean prevalence of dental fluorosis for the studied population was 16.6%, where the very mild category (8.5%) predominated. Maria May was the most affected school with dental fluorosis (41.5%) and the fluoride concentration in drinking water after analyses was 1.58%. The results of this study indicate the presence of an inverse relationship between fluoride concentrations in the water collected at the schools and the prevalence of dental fluorosis in the permanent dentition of school children, but not in the primary dentition.

Calculating crop water requirement satisfaction in the West Africa Sahel with remotely sensed soil moisture

USGS Publications Warehouse

McNally, Amy; Gregory J. Husak,; Molly Brown,; Carroll, Mark L.; Funk, Christopher C.; Soni Yatheendradas,; Kristi Arsenault,; Christa Peters-Lidard,; Verdin, James

2015-01-01

The Soil Moisture Active Passive (SMAP) mission will provide soil moisture data with unprecedented accuracy, resolution, and coverage, enabling models to better track agricultural drought and estimate yields. In turn, this information can be used to shape policy related to food and water from commodity markets to humanitarian relief efforts. New data alone, however, do not translate to improvements in drought and yield forecasts. New tools will be needed to transform SMAP data into agriculturally meaningful products. The objective of this study is to evaluate the possibility and efficiency of replacing the rainfall-derived soil moisture component of a crop water stress index with SMAP data. The approach is demonstrated with 0.1°-resolution, ~10-day microwave soil moisture from the European Space Agency and simulated soil moisture from the Famine Early Warning Systems Network Land Data Assimilation System. Over a West Africa domain, the approach is evaluated by comparing the different soil moisture estimates and their resulting Water Requirement Satisfaction Index values from 2000 to 2010. This study highlights how the ensemble of indices performs during wet versus dry years, over different land-cover types, and the correlation with national-level millet yields. The new approach is a feasible and useful way to quantitatively assess how satellite-derived rainfall and soil moisture track agricultural water deficits. Given the importance of soil moisture in many applications, ranging from agriculture to public health to fire, this study should inspire other modeling communities to reformulate existing tools to take advantage of SMAP data.

Evaluation of phytotoxicity effect of olive mill wastewater treated by different technologies on seed germination of barley (Hordeum vulgare L.).

PubMed

Rusan, Munir J M; Albalasmeh, Ammar A; Zuraiqi, Said; Bashabsheh, Mohammad

2015-06-01

Olive-mill wastewater (OMW) is a by-product effluent of olive oil extraction process that is produced in large amount in the Mediterranean region. OMW is believed to induce phytotoxic effect on organisms including seed germination and plant growth. The objective of this study was to evaluate the impact of untreated and treated OMW with different techniques on seed germination of barley (Hordeum vulgare L.). The following treatments were investigated: (1) tap water (control); (2) OMW treated by aerobic biological technology in a Jacto Reactor (JR); (3) OMW treated by solar fenton oxidation (SFO); (4) OMW treated by microfiltration followed by nanofiltration (MF+NF); (5) OMW treated by microfiltration followed by reverse osmosis (MF+RO) process; (6) diluted OMW with tap water (25 % OMW); (7) diluted OMW with tap water (50 % OMW); (8) diluted OMW with tap water (75 % OMW); and (9) untreated OMW (100 % OMW). A germination test was conducted in an incubator at temperature of 23 (∘)C. In each petri dish, a filter paper was mounted and ten seeds of barley were placed on the filter paper. Five milliliter of water were added to each petri dish. The seed germination was determined by counting the number of germinated seeds to calculate the percentage of germination (G %). Germination rate index (GRI), seed vigor index (SVI), and phytotoxicity index (PI) were also calculated. Then, the dry weights and lengths of the shoots and the roots of the germinated seeds were measured. The results show that 100, 75, and 50 %OMW were very phytotoxic and completely prohibited seed germination. However, phytotoxicity decreased significantly following treatments of OMW with all techniques investigated and by the 25 % OMW dilution, as results of removing the phenols and other phytotoxic organic compounds from the OMW or by diluting it. This was evidenced by relative enhancement of the dry weights and lengths of shoot and root as well as the G %, GRI, SVG, and PI. It was concluded that if OMW will be used for irrigating crops, it has to be first treated or diluted with tap water at a ratio of 1:3 OMW:water at least. The most efficient treatment techniques in reducing the phytotoxicity of OMW were the MF+RO, followed by SFO and JR.

Ecohydrological Responses to Hurricane Harvey across South-Central Texas a Multidisciplinary Approach of the Texas Water Observatory

NASA Astrophysics Data System (ADS)

Jaimes, A.; Gaur, N.; Aparecido, L. M. T.; Everett, M. E.; Knappett, P.; Lawing, M.; Majumder, S.; Miller, G. R.; Moore, G. W.; Morgan, C.; Mitra, B.; Noormets, A.; Mohanty, B.

2017-12-01

The unprecedented destructive hurricane Harvey struck eastern Texas from August 25th to 29th, 2017. As the hurricane moved through the region, it dropped the equivalent of one year of precipitation within a five-day period, with peak accumulations near 165 cm. Rainfall intensity and distribution varied across the region but Harris County and portions of the lower Brazos River Basin experienced devastating flooding due to high run-off and water accumulation in the built-up area. In this study, we use a multidisciplinary approach to quantify the dynamics of carbon and water flux at different spatiotemporal resolution across land types both in and outside of the path of hurricane Harvey using a combination of remote sensing and fixed monitoring platforms of the Texas Water Observatory (TWO). We used LANDSAT imagery to compute Soil Adjusted Vegetation Index, Enhanced Vegetation Index, and Normalized Difference Moisture Index. MODIS ET, GPP, and sap flow data were used in combination with eddy covariance and meteorological data from seven sites of the TWO representative of biomes ranging from low tidal salt marsh of the Gulf Coastal Plain, Shrubland, Improved Pasture, Mixed and Native Prairies, and Crop sites. We hypothesize alteration in ecohydrological characteristics across land types, which were in the path of hurricane due to changes in vegetation structure. Specifically we used trend analysis to detect structural changes in temporal dynamics of sap flow, ET, and carbon to pulse response. In addition, we monitored trace metal concentration of soil and water pores before and immediately after the hurricane in order to predict the potential of any of the toxic metal (loid)s being mobilized in the natural water resources as a function of the changes in the redox gradient. Preliminary results indicated that tree water use was reduced on average 30% below normal days. Porewater concentration of some of the metal (loid) concentration increased (Fe, Mn, Co, As, Sb, Pb) from pre- to post-hurricane scenario. Overall, the integrative approach adopted by TWO in evaluating the impact of Hurricane Harvey on ecosystem structure and function has the potential to provide the baseline information to manage and mitigate the effects of future events with similar characteristics.

Simultaneous PLIF and PIV measurement of a near field turbulent immiscible buoyant oil jet fragmentation in water using liquid-liquid refractive index matching

NASA Astrophysics Data System (ADS)

Xue, Xinzhi; Katz, Joseph

2017-11-01

Very little experimental data exits on the flow structure in the near field of a crude oil jet fragmenting in water because of inability to probe dense droplet cloud. Refractive index-matching is applied to overcome this challenge by using silicone oil and sugar water as a surrogate liquid pair. Their density ratio, viscosity ratio, and interfacial tension are closely matched with those of crude oil and seawater. Simultaneous PLIF and PIV measurements are conducted by fluorescently tagging the oil and seeding both phases with particles. With increasing jet Reynolds and Weber numbers, the oil plume breakup occurs closer to the nozzle, the spreading angle of the jet increases, and the droplet sizes decrease. The varying spread rate is attributed to differences in droplet size distributions. The location of primary oil breakup is consistent with the region of high strain rate fluctuations. What one may perceive as oil droplets in opaque fluids actually consists of multi-layers containing water droplets, which sometimes encapsulate smaller oil droplets, creating a ``Russian Doll'' like phenomenon. This system forms as ligaments of oil and water wrap around each other during entrainment. Results include profiles of mean velocity and turbulence parameters along with energy spectra. Gulf of Mexico Research Inititave.

Manipulating plant geometry to improve microclimate, grain yield, and harvest index in grain sorghum.

PubMed

Thapa, Sushil; Stewart, Bob A; Xue, Qingwu; Chen, Yuanquan

2017-01-01

Cultivar selection, planting geometry, and plant population are the key factors determining grain sorghum yields in water deficit areas. The objective of this study was to investigate whether clump geometry (three plants clustered) improves microclimate within crop canopy when plants are grown under varying water levels. In a 2-yr sorghum (Sorghum bicolor L. Moench) greenhouse study, plants were grown at two geometries (clump and conventional evenly spaced planting, ESP), two water levels (high and low, representing well-watered and water-limited condition, respectively), and three soil surface treatments (lid covered, straw-mulched, and bare). Air temperature and relative humidity (RH) within the plant canopy were measured every five minutes at different growth stages. Mean vapor pressure deficits (VPDs) within the clumps were consistently lower than those for ESPs, indicating that clumps improved the microclimate. Clumps had significantly higher harvest index (HI) compared to ESPs (0.48 vs. 0.43), which was largely due to clumps having an average of 0.4 tillers per plant compared to 1.2 tillers per plant for ESPs. Grain yield in the current study was similar between clumps and ESPs. However, our results suggest that improved microclimate was likely a reason for clumps producing significantly higher grain yields compared to ESPs in previous studies.

Manipulating plant geometry to improve microclimate, grain yield, and harvest index in grain sorghum

PubMed Central

Stewart, Bob A.; Xue, Qingwu; Chen, Yuanquan

2017-01-01

Cultivar selection, planting geometry, and plant population are the key factors determining grain sorghum yields in water deficit areas. The objective of this study was to investigate whether clump geometry (three plants clustered) improves microclimate within crop canopy when plants are grown under varying water levels. In a 2-yr sorghum (Sorghum bicolor L. Moench) greenhouse study, plants were grown at two geometries (clump and conventional evenly spaced planting, ESP), two water levels (high and low, representing well-watered and water-limited condition, respectively), and three soil surface treatments (lid covered, straw-mulched, and bare). Air temperature and relative humidity (RH) within the plant canopy were measured every five minutes at different growth stages. Mean vapor pressure deficits (VPDs) within the clumps were consistently lower than those for ESPs, indicating that clumps improved the microclimate. Clumps had significantly higher harvest index (HI) compared to ESPs (0.48 vs. 0.43), which was largely due to clumps having an average of 0.4 tillers per plant compared to 1.2 tillers per plant for ESPs. Grain yield in the current study was similar between clumps and ESPs. However, our results suggest that improved microclimate was likely a reason for clumps producing significantly higher grain yields compared to ESPs in previous studies. PMID:28264051

Assessing the Variability of Heavy Metal Concentrations in Liquid-Solid Two-Phase and Related Environmental Risks in the Weihe River of Shaanxi Province, China

PubMed Central

Song, Jinxi; Yang, Xiaogang; Zhang, Junlong; Long, Yongqing; Zhang, Yan; Zhang, Taifan

2015-01-01

Accurate estimation of the variability of heavy metals in river water and the hyporheic zone is crucial for pollution control and environmental management. The biotoxicities and potential ecological risks of heavy metals (Cu, Zn, Pb, Cd) in a solid-liquid two-phase system were estimated using the Geo-accumulation Index, Potential Ecological Risk Assessment and Quality Standard Index methods in the Weihe River of Shaanxi Province, China. Water and sediment samples were collected from five study sites during spring, summer and winter, 2013. The dominant species in the streambed sediments were chironomids and flutter earthworm, whose bioturbation mainly ranged from 0 to 20 cm. The concentrations of heavy metals in surface water and pore water varied obviously in spring and summer. The degrees of concentration of Cu and Cd in spring and summer were higher than the U.S. water quality Criteria Maximum Concentrations. Furthermore, the biotoxicities of Pb and Zn demonstrated season-spatial variations. The concentrations of Cu, Zn, Pb and Cd in spring and winter were significantly higher than those in summer, and the pollution levels also varied obviously in different layers of the sediments. Moreover, the pollution level of Cd was the most serious, as estimated by all three assessment methods. PMID:26193293

Surrogate Immiscible Liquid Solution Pairs with Refractive Indexes Matchable Over a Wide Range of Density and Viscosity Ratios

NASA Astrophysics Data System (ADS)

Saksena, Rajat; Christensen, Kenneth T.; Pearlstein, Arne J.

2014-11-01

Use of laser diagnostics in liquid-liquid flows is limited by refractive index mismatch. This can be avoided using a surrogate pair of immiscible index-matched liquids, with density and viscosity ratios matching those of the original liquid pair. We demonstrate that a wide range of density and viscosity ratios is accessible using aqueous solutions of 1,2-propanediol and CsBr (for which index, density, and viscosity are available), and solutions of light and heavy silicone oils and 1-bromooctane (for which we measured the same properties at 119 compositions). For each liquid phase, polynomials in the composition variables were fitted to index and density and to the logarithm of kinematic viscosity, and the fits were used to determine accessible density and viscosity ratios for each matchable index. Index-matched solution pairs can be prepared with density and viscosity ratios equal to those for water-liquid CO2 at 0oC over a range of pressure, and for water-crude oil and water-trichloroethylene, each over a range of temperature. For representative index-matched solutions, equilibration changes index, density, and viscosity only slightly, and chemical analysis show that no component of either solution has significant interphase solubility. Partially supported by Intl. Inst. for Carbon-Neutral Energy Research.

Water stress index for alkaline fen habitat based on UAV and continuous tower measurements of canopy infrared temperature

NASA Astrophysics Data System (ADS)

Ciężkowski, Wojciech; Jóźwiak, Jacek; Chormański, Jarosław; Szporak-Wasilewska, Sylwia; Kleniewska, Małgorzata

2017-04-01

This study is focused on developing water stress index for alkaline fen, to evaluate water stress impact on habitat protected within Natura 2000 network: alkaline fens (habitat code:7230). It is calculated based on continuous measurements of air temperature, relative humidity and canopy temperature from meteorological tower and several UAV flights for canopy temperature registration. Measurements were taken during the growing season in 2016 in the Upper Biebrza Basin in north-east Poland. Firstly methodology of the crop water stress index (CWSI) determination was used to obtained non-water stress base line based on continuous measurements (NWSBtower). Parameters of NWSBtower were directly used to calculate spatial variability of CWSI for UAV thermal infrared (TIR) images. Then for each UAV flight day at least 3 acquisition were performed to define NWSBUAV. NWSBUAV was used to calculate canopy waters stress for whole image relative to the less stressed areas. The spatial distribution of developed index was verified using remotely sensed indices of vegetation health. Results showed that in analysed area covered by sedge-moss vegetation NWSB cannot be used directly. The proposed modification of CWSI allows identifying water stress in alkaline fen habitats and was called as Sedge-Moss Water Stress Index (SMWSI). The study shows possibility of usage remotely sensed canopy temperature data to detect areas exposed to the water stress on wetlands. This research has been carried out under the Biostrateg Programme of the Polish National Centre for Research and Development (NCBiR), project No.: DZP/BIOSTRATEG-II/390/2015: The innovative approach supporting monitoring of non-forest Natura 2000 habitats, using remote sensing methods (HabitARS).

Monitoring land cover dynamics in the Aral Sea region by remote sensing

NASA Astrophysics Data System (ADS)

Kozhoridze, Giorgi; Orlovsky, Leah; Orlovsky, Nikolai

2012-10-01

The Aral Sea ecological crisis resulted from the USSR government decision in 1960s to deploy agricultural project for cotton production in Central Asia. Consequently water flow in the Aral Sea decreased drastically due to the regulation of Amydarya and Syrdarya Rivers for irrigation purposes from 55-60 km3 in 1950s to 43 km3 in 1970s, 4 km3 in 1980s and 9-10 km3 in 2000s. Expert land cover classification approach gives the opportunity to use the unlimited variable for classification purposes. The band algebra (band5/band4 and Band4/Band3) and remote sensing indices (Normalized differential Salinity Index (NDSI), Salt Pan Index (SPI), Salt Index (SI), Normalized difference Vegetation Index (NDVI), Albedo, Crust Index) utilized for the land cover classification has shown satisfactory result with classification overall accuracy 86.9 % and kappa coefficient 0.85. Developed research algorithm and obtained results can support monitoring system, contingency planning development, and improvement of natural resources rational management.

Soil Erosion Risk Map based on irregularity of the vegetative activity

NASA Astrophysics Data System (ADS)

Saa-Requejo, Antonio; Tarquis, Ana Maria; Martín-Sotoca, Juan J.; Valencia, Jose L.; Gobin, Anne; Rodriguez-Sinobas, Leonor

2016-04-01

Because of the difficulties to build on both daily rainfall and base shorter time, we explored the possibilities of building indexes based on land cover, which also provide us the opportunity to evaluate their evolution over time. We consider the Fournier index (Fournier, 1960) which is used to assess the rainfall erosivity based on monthly rainfall, alternatively to use of the rainfall intensity in time bases under one hour (eg., van der Knijff et al., 1999; Shamshad et al, 2008). This index can also be interpreted as an index of irregularity and representing a ratio between maximum monthly precipitation and annual rainfall. We propose to calculate this irregularity in terms of irregularity of the vegetative activity. This activity is related to precipitation, but also with the availability of water in the soil reservoir and land use. Therefore, we propose a kind of Fournier index on the effective use of water, which is also closely related to variations in infiltration. Higher is the presence of vegetation higher is the effective use of water. For this "modified Fourier index" we used the NDVI (Normalized Difference Vegetation Index) as index of available vegetative activity, which is widely reported in the literature (Jensen, 2000). Initial calculations have been done with MODIS 500 x 500 m satellite data. The selected area was Cega-Eresma-Adaja subbasin during the period from 2009 to 2012. We selected 8 days composite images product. The calculation of the valid values to eliminate areas with clouds or snow is performed according to the criteria of Martinez Sotoca (2014), ie with a Saturation (based on HSL color model) greater or equal to 0.15. Then, an average of these values was estimated to represent each month of the year. The results are very interesting when we compare Modified Fournier Index on NDVIs with the map of potential soil loss. We have found surprisingly similar patterns and practical equivalence between several classes. Therefore, the Modified Fournier Index on NDVI values seems to synthesize the different parameters of the USLE, referring to rainfall, soil, geomorphology and vegetation cover. Acknowledgements Authors are grateful to TALE project (CICYT PCIN-2014-080) and DURERO project (Env.C1.3913442) for their financial support. References Fournier, F. (1960), Climat et erosion. P.U.F. Paris. Jensen, J.R. (2000). Remote Sensing of the Environment: An Earth Resource Perpective, Prentice Hall, New Jersey. Martínez Sotoca, J. J. (2014) estructura espacial de la sequía en pastos y sus aplicaciones en el seguro agrario indexado. (In Spanish) Master Thesis, UPM. Shamshad, A., Azhari M.N., Isaac, M.H., wan Hussin, W.M.A., Parida, B.P.. (2008). Development of an appropriate procedure for estimation of RUSLE EI30 index and preparation of erosivity maps for Pulau Penang in Peninsular Malaysia. Catena, 72, 423-432. van der Knijff, J.M., Jones, R.J.A., Montanarella, L. (1999). Soil Erosion Risk Assessment Italy Soil Erosion Risk Assessment in Italy. European Commission Soil Bureau Joint Research Centre European Commission. EUR 19022EN.

Comparative study of carbonic anhydrase activity in waters among different geological eco-environments of Yangtze River basin and its ecological significance.

PubMed

Nzung'a, Sila Onesmus; Pan, Weizhi; Shen, Taiming; Li, Wei; Qin, Xiaoqun; Wang, Chenwei; Zhang, Liankai; Yu, Longjiang

2018-04-01

This study provides the presence of carbonic anhydrase (CA) activity in waters of the Yangtze River basin, China, as well as the correlation of CA activity with HCO 3 - concentration and CO 2 sink flux. Different degrees of CA activity could be detected in almost all of the water samples from different geological eco-environments in all four seasons. The CA activity of water samples from karst areas was significantly higher than from non-karst areas (PP3 - concentration (r=0.672, P2 sink flux (r=0.602, P=0.076) in karst areas. This suggests that CA in waters might have a promoting effect on carbon sinks for atmospheric CO 2 in karst river basins. In conditions of similar geological type, higher CA activity was generally detected in water samples taken from areas that exhibited better eco-environments, implying that the CA activity index of waters could be used as an indicator for monitoring ecological environments and protection of river basins. These findings suggest that the role of CA in waters in the karst carbon sink potential of river basins is worthy of further in-depth studies. Copyright © 2017. Published by Elsevier B.V.

Assessment of Shallow-Water Habitat Availability in Modified Dike Structures, Lower Missouri River, 2004

USGS Publications Warehouse

Jacobson, Robert B.; Elliott, Caroline M.; Johnson, Harold E.

2004-01-01

This study documented the effects of wing-dike notching on the availabilit of shallow water habitat in the Lower Missouri River. Five wing dikes were surveyed in late May 2004 after they were notched in early May as part of shallow-water habitat (SWH) rehabilitation activities undertaken by the U.S. Army Corps of Engineers. Surveys included high-resolution hydroacoustic depth, velocity, and substrate mapping. Relations of bottom elevations within the wing dike fields to index discharges and water-surface elevations indicate that little habitat meeting the SWH definition was created immediately following notching. This result is not unexpected, as significant geomorphic adjustment may require large flow events. Depth, velocity, and substrate measurements in the post-rehabilitation time period provide baseline data for monitoring ongoing changes. Differences in elevation and substrate were noted at all sites. Most dike fields showed substantial aggradation and replacement of mud substrate with sandier sediment, although the changes did not result in increased availability of SWH at the index discharge. It is not known how much of the elevation and substrate changes can be attributed directly to notching and how much would result from normal sediment transport variation.

Nanophotonic sensors for oil sensing (Conference Presentation)

NASA Astrophysics Data System (ADS)

Salemink, Huub W.; Liu, Yazhao

2017-02-01

The proof of concept for a photonic cavity sensor for oil, water and gas detection is reported. The optical design employs an optimized photonic crystal cavity with fluidic infiltration of gas, water or (reservoir) oils. The 3D design and simulation is discussed, followed by the nanofabrication in standard silicon on insulator wafers (SoI). Using an optofluidic cicuit with PDMS channels, the fluid flow to the photonic cavity is controlled with syringe pumps. The variations in dielectric value (refractive index) change with the involved media result in a shift of the cavity resonant wavelength. For fluid change from water to typical oil (refractive index difference of 0.12), we report a wavelenght shift of up to 12 nm at the measurement wavelength of 1550 nm, in very good agreement with the simulations. We follow the optical response at a fixed wavelength, when feeding alternate flows or bubbles of oil/water through the optofluidic chip, and observe the flow pattern on camera. Finally we discuss the outlook and antifouling of the sensor with a special design. This work is supported by Shell Global Solutions. Appl.Phys.Lett., 106, 031116 (2015) J.Lightw.Technol., 33, 3672 (2015)

Reproductive allocation strategies in desert and Mediterranean populations of annual plants grown with and without water stress.

PubMed

Aronson, J; Kigel, J; Shmida, A

1993-03-01

Reproductive effort (relative allocation of biomass to diaspore production) was compared in matched pairs of Mediterranean and desert populations of three unrelated annual species, Erucaria hispanica (L.) Druce, Bromus fasciculatus C. Presl. and Brachypodium distachyon (L.) Beauv., grown under high and low levels of water availability in a common-environment experiment. Desert populations in all three species showed higher reproductive effort than corresponding Mediterranean populations, as expressed by both a reproductive index (RI= reproductive biomass/vegetative biomass), and a reproductive efficiency index (REI=number of diaspores/total plant biomass). Moreover, in E. hispanica and Brachypodium distachyon, inter-populational differences in reproductive effort were greater under water stress, the main limiting factor for plant growth in the desert. These results indicate that variability in reproductive effort in response to drought is a critical and dynamic component of life history strategies in annual species in heterogeneous, unpredictable xeric environments. When subjected to water stress the Mediterranean populations of E. hispanica and B. distachyon showed greater plasticity (e.g. had a greater reduction) in reproductive effort than the desert populations, while in Bromus fasciculatus both populations showed similar amounts of plasticity.

Dental caries, its surface susceptibility and dental fluorosis in South India.

PubMed

Acharya, Shashidhar

2005-12-01

To correlate water fluoride levels with dental caries and dental fluorosis in areas with different levels of fluoride in the drinking water and to establish the surface susceptibility of dental caries in an endemic fluoride area. 544 schoolchildren 12 to 15 years of age from the Davangere region of India were examined. The DMFS index was used to measure dental caries, which was further differentiated into smooth surface and pit and fissure lesions. Dean's index was used to diagnose dental fluorosis. Five villages with fluoride levels ranging from 0.43 ppm to 3.41 ppm were studied. There was a highly significant negative correlation (r = -0.16) between water fluoride levels and dental caries. Dental fluorosis increased from 16% at 0.43 ppm to 100% at 3.41 ppm. Pit and fissure lesions made up the vast majority of the lesions in all the villages and showed a decreasing trend with increasing fluoride levels, however no such trend was seen for smooth surface lesions. Water fluoride was an important factor responsible for the low caries prevalence. The prevalence of fluorosis and low caries even in low fluoride areas may point to a halo effect.