Mapping Rural Areas with Widespread Plastic Covered Vineyards Using True Color Aerial Data

Directory of Open Access Journals (Sweden)

Eufemia Tarantino

2012-06-01

Full Text Available Plastic covering is used worldwide to protect crops against damaging growing conditions. This agricultural practice raises some controversial issues. While it significantly impacts on local economic vitality, plasticulture also shows several environmental affects. In the Apulia Region (Italy the wide-spreading of artificial plastic coverings for vineyard protection has showed negative consequences on the hydrogeological balance of soils as well as on the visual quality of rural landscape. In order to monitor and manage this phenomenon, a detailed site mapping has become essential. In this study an efficient object-based classification procedure from Very High Spatial Resolution (VHSR true color aerial data was developed on eight test areas located in the Ionian area of the Apulia Region in order to support the updating of the existing land use database aimed at plastic covered vineyard monitoring.

Standard Enucleation with Aluminium Oxide Implant (Bioceramic Covered with Patient's Sclera

Directory of Open Access Journals (Sweden)

Gian Luigi Zigiotti

2012-01-01

Full Text Available Purpose. We describe in our study a modified standard enucleation, using sclera harvested from the enucleated eye to cover the prosthesis in order to insert a large porous implant and to reduce postoperative complication rates in a phthisis globe. Methods. We perform initially a standard enucleation. The porous implant (Bioceramic is then covered only partially by the patient's sclera. The implant is inserted in the posterior Tenon's space with the scleral covering looking at front. All patients were followed at least for twelve months (average followup 16 months. Results. We performed nineteen primary procedures (19 patients, 19 eyes, M; F and secondary, to fill the orbital cavity in patients already operated by standard evisceration (7 patients, 7 eyes. There were no cases of implant extrusion. The orbital volume was well reintegrated. Conclusion. Our procedure was safe and effective. All patients had a good cosmetic result after final prosthetic fitting and we also achieved good prothesis mobility.

Generating local scale land use/cover change scenarios: case studies of high-risk mountain areas

Science.gov (United States)

Malek, Žiga; Glade, Thomas; Boerboom, Luc

2014-05-01

The relationship between land use/cover changes and consequences to human well-being is well acknowledged and has led to higher interest of both researchers and decision makers in driving forces and consequences of such changes. For example, removal of natural vegetation cover or urban expansion resulting in new elements at risk can increase hydro-meteorological risk. This is why it is necessary to study how the land use/cover could evolve in the future. Emphasis should especially be given to areas experiencing, or expecting, high rates of socio-economic change. A suitable approach to address these changes is scenario development; it offers exploring possible futures and the corresponding environmental consequences, and aids decision-making, as it enables to analyse possible options. Scenarios provide a creative methodology to depict possible futures, resulting from existing decisions, based on different assumptions of future socio-economic development. They have been used in various disciplines and on various scales, such as flood risk and soil erosion. Several studies have simulated future scenarios of land use/cover changes at a very high success rate, however usually these approaches are tailor made for specific case study areas and fit to available data. This study presents a multi-step scenario generation framework, which can be transferable to other local scale case study areas, taking into account the case study specific consequences of land use/cover changes. Through the use of experts' and decision-makers' knowledge, we aimed to develop a framework with the following characteristics: (1) it enables development of scenarios that are plausible, (2) it can overcome data inaccessibility, (3) it can address intangible and external driving forces of land use/cover change, and (4) it ensures transferability to other local scale case study areas with different land use/cover change processes and consequences. To achieve this, a set of different methods is applied

Changing landscape in the Three Gorges Reservoir Area of Yangtze River from 1977 to 2005: Land use/land cover, vegetation cover changes estimated using multi-source satellite data

Science.gov (United States)

Zhang, Jixian; Zhengjun, Liu; Xiaoxia, Sun

2009-12-01

The eco-environment in the Three Gorges Reservoir Area (TGRA) in China has received much attention due to the construction of the Three Gorges Hydropower Station. Land use/land cover changes (LUCC) are a major cause of ecological environmental changes. In this paper, the spatial landscape dynamics from 1978 to 2005 in this area are monitored and recent changes are analyzed, using the Landsat TM (MSS) images of 1978, 1988, 1995, 2000 and 2005. Vegetation cover fractions for a vegetation cover analysis are retrieved from MODIS/Terra imagery from 2000 to 2006, being the period before and after the rising water level of the reservoir. Several analytical indices have been used to analyze spatial and temporal changes. Results indicate that cropland, woodland, and grassland areas reduced continuously over the past 30 years, while river and built-up area increased by 2.79% and 4.45% from 2000 to 2005, respectively. The built-up area increased at the cost of decreased cropland, woodland and grassland. The vegetation cover fraction increased slightly. We conclude that significant changes in land use/land cover have occurred in the Three Gorges Reservoir Area. The main cause is a continuous economic and urban/rural development, followed by environmental management policies after construction of the Three Gorges Dam.

Land cover in single-family housing areas and how it correlates with urban form

DEFF Research Database (Denmark)

Nielsen, Mette Boye; Jensen, Marina Bergen

2015-01-01

Land cover composition is a valuable indicator of the ecological performance of a city. Single-family housing areas constitute a substantial part of most cities and may as such play an important role for sustainable urban development. From aerial photos we performed detailed GIS-based mapping...... of land cover in three detached single-family housing areas in Denmark of different urban form but comparable housing densities (ranging from 10.0 to 11.3 houses per hectare). The findings were subjected to statistical analysis and landscape metrics. Land cover varied with urban form: A traditional...... spatial configuration with rectangular parcels contained significantly more vegetation and less impervious surfaces per parcel than newer Radburn-inspired configurations with more quadratic parcels. Correlation analysis showed size of paved access ways to be positively correlated with distance from road...

Decision Tree and Texture Analysis for Mapping Debris-Covered Glaciers in the Kangchenjunga Area, Eastern Himalaya

Directory of Open Access Journals (Sweden)

Adina Racoviteanu

2012-10-01

Full Text Available In this study we use visible, short-wave infrared and thermal Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER data validated with high-resolution Quickbird (QB and Worldview2 (WV2 for mapping debris cover in the eastern Himalaya using two independent approaches: (a a decision tree algorithm, and (b texture analysis. The decision tree algorithm was based on multi-spectral and topographic variables, such as band ratios, surface reflectance, kinetic temperature from ASTER bands 10 and 12, slope angle, and elevation. The decision tree algorithm resulted in 64 km2 classified as debris-covered ice, which represents 11% of the glacierized area. Overall, for ten glacier tongues in the Kangchenjunga area, there was an area difference of 16.2 km2 (25% between the ASTER and the QB areas, with mapping errors mainly due to clouds and shadows. Texture analysis techniques included co-occurrence measures, geostatistics and filtering in spatial/frequency domain. Debris cover had the highest variance of all terrain classes, highest entropy and lowest homogeneity compared to the other classes, for example a mean variance of 15.27 compared to 0 for clouds and 0.06 for clean ice. Results of the texture image for debris-covered areas were comparable with those from the decision tree algorithm, with 8% area difference between the two techniques.

Evapotranspiration Cover for the 92-Acre Area Retired Mixed Waste Pits:Interim CQA Report

International Nuclear Information System (INIS)

2011-01-01

This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. Construction was approved by the Nevada Division of Environmental Protection (NDEP) under the Approval of Corrective Action Decision Document/Corrective Action Plan (CADD/CAP) for Corrective Action Unit (CAU) 111: Area 5 WMD Retired Mixed Waste Pits, Nevada National Security Site, Nevada, on January 6, 2011, pursuant to Subpart XII.8a of the Federal Facility Agreement and Consent Order. The project is located in Area 5 of the Radioactive Waste Management Complex (RWMC) at the Nevada National Security Site (NNSS), formerly known as the Nevada Test Site, located in southern Nevada, approximately 65 miles northwest of Las Vegas, Nevada, in Nye County. The project site, in Area 5, is located in a topographically closed basin approximately 14 additional miles north of Mercury Nevada, in the north-central part of Frenchman Flat. The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste. The 92-Acre Area encompasses the southern portion of the Area 5 RWMS, which has been designated for the first final closure operations. This area contains 13 Greater Confinement Disposal (GCD) boreholes, 16 narrow trenches, and 9 broader pits. With the exception of two active pits (P03 and P06), all trenches and pits in the 92-Acre Area had operational covers approximately 2.4 meters thick, at a minimum, in most areas when this project began. The units within the 92-Acre Area are grouped into the following six informal categories based on physical location

Evapotranspiration Cover for the 92-Acre Area Retired Mixed Waste Pits:Interim CQA Report

Energy Technology Data Exchange (ETDEWEB)

The Delphi Groupe, Inc., and J. A. Cesare and Associates, Inc.

2011-06-20

This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. Construction was approved by the Nevada Division of Environmental Protection (NDEP) under the Approval of Corrective Action Decision Document/Corrective Action Plan (CADD/CAP) for Corrective Action Unit (CAU) 111: Area 5 WMD Retired Mixed Waste Pits, Nevada National Security Site, Nevada, on January 6, 2011, pursuant to Subpart XII.8a of the Federal Facility Agreement and Consent Order. The project is located in Area 5 of the Radioactive Waste Management Complex (RWMC) at the Nevada National Security Site (NNSS), formerly known as the Nevada Test Site, located in southern Nevada, approximately 65 miles northwest of Las Vegas, Nevada, in Nye County. The project site, in Area 5, is located in a topographically closed basin approximately 14 additional miles north of Mercury Nevada, in the north-central part of Frenchman Flat. The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste. The 92-Acre Area encompasses the southern portion of the Area 5 RWMS, which has been designated for the first final closure operations. This area contains 13 Greater Confinement Disposal (GCD) boreholes, 16 narrow trenches, and 9 broader pits. With the exception of two active pits (P03 and P06), all trenches and pits in the 92-Acre Area had operational covers approximately 2.4 meters thick, at a minimum, in most areas when this project began. The units within the 92-Acre Area are grouped into the following six informal categories based on physical location

Proposed hybrid-classifier ensemble algorithm to map snow cover area

Science.gov (United States)

Nijhawan, Rahul; Raman, Balasubramanian; Das, Josodhir

2018-01-01

Metaclassification ensemble approach is known to improve the prediction performance of snow-covered area. The methodology adopted in this case is based on neural network along with four state-of-art machine learning algorithms: support vector machine, artificial neural networks, spectral angle mapper, K-mean clustering, and a snow index: normalized difference snow index. An AdaBoost ensemble algorithm related to decision tree for snow-cover mapping is also proposed. According to available literature, these methods have been rarely used for snow-cover mapping. Employing the above techniques, a study was conducted for Raktavarn and Chaturangi Bamak glaciers, Uttarakhand, Himalaya using multispectral Landsat 7 ETM+ (enhanced thematic mapper) image. The study also compares the results with those obtained from statistical combination methods (majority rule and belief functions) and accuracies of individual classifiers. Accuracy assessment is performed by computing the quantity and allocation disagreement, analyzing statistic measures (accuracy, precision, specificity, AUC, and sensitivity) and receiver operating characteristic curves. A total of 225 combinations of parameters for individual classifiers were trained and tested on the dataset and results were compared with the proposed approach. It was observed that the proposed methodology produced the highest classification accuracy (95.21%), close to (94.01%) that was produced by the proposed AdaBoost ensemble algorithm. From the sets of observations, it was concluded that the ensemble of classifiers produced better results compared to individual classifiers.

Variations of Near Surface Energy Balance Caused by Land Cover Changes in the Semiarid Grassland Area of China

Directory of Open Access Journals (Sweden)

Qun’ou Jiang

2014-01-01

Full Text Available This study applies the Dynamics of Land System (DLS model to simulating the land cover under the designed scenarios and then analyzes the effects of land cover conversion on energy flux in the semiarid grassland area of China with the Weather Research and Forecasting (WRF model. The results indicate that the grassland will show a steadily upgrowing trend under the coordinated environmental sustainability (CES scenario. Compared to the CES scenario, the rate of increase in grassland cover is lower, while the rate of increase in urban land cover will be higher under the rapid economic growth (REG scenario. Although the conversion from cropland to grassland will reduce the energy flux, the expansion of urban area and decreasing of forestry area will bring about more energy flux. As a whole, the energy flux of near surface will obviously not change under the CES scenario, and the climate therefore will not be possible to be influenced greatly by land cover change. The energy flux under the REG scenario is higher than that under the CES scenario. Those research conclusions can offer valuable information for the land use planning and climate change adaptation in the semiarid grassland area of China.

[Evaluation of pollution of an urban area by level of heavy metals in snow cover].

Science.gov (United States)

Stepanova, N V; Khamitova, R Ia; Petrova, R S

2003-01-01

The goal of this study was to systematize various methodological approaches to evaluating the contamination of the snow cover with heavy metals (HM) by using Kazan, an industrial city with diversified industry, as an example. The findings suggest that it is necessary to characterize the contamination of the snow cover by the actual entrance of an element per area unit of the snow cover for a definite period of time rather than by the concentration of TM in the volume unit of snow water (mg/l), which minimizes the uncertainties with spatial and temporary snow cover variations. The index of the maximum allowable entrance, which is of practical value, may be used to objectively calibrate the pollution of the snow cover, by estimating the amount of a coming element and its toxicity.

Evapotranspiration Cover for the 92-Acre Area Retired Mixed Waste Pits, Area 5 Waste Management Division, Nevada National Security Site, Final CQA Report

International Nuclear Information System (INIS)

2012-01-01

The report is the Final Construction Quality Assurance (CQA) Report for the 92-Acrew Evapotranspiration Cover, Area 5 Waste Management Division Retired Mixed Waste Pits, Nevada National Security Site, Nevada, for the period of January 20, 2011, to January 31, 2012 The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste. The 92-Acre Area encompasses the southern portion of the Area 5 RWMS, which has been designated for the first final closure operations. This area contains 13 Greater Confinement Disposal (GCD) boreholes, 16 narrow trenches, and 9 broader pits. With the exception of two active pits (P03 and P06), all trenches and pits in the 92-Acre Area had operational covers approximately 2.4 meters thick, at a minimum, in most areas when this project began. The units within the 92-Acre Area are grouped into the following six informal categories based on physical location, waste types and regulatory requirements: (1) Pit 3 Mixed Waste Disposal Unit (MWDU); (2) Corrective Action Unit (CAU) 111; (3) CAU 207; (4) Low-level waste disposal units; (5) Asbestiform low-level waste disposal units; and (6) One transuranic (TRU) waste trench.

Determination of priority areas for the re-establishment of forest cover, based on the use of geotechnologies

Directory of Open Access Journals (Sweden)

Nelson Wellausen Dias

2012-12-01

Full Text Available The determination of priority areas for the re-establishment of forest cover in watersheds is directly associated to the probability of effective success of restoration processes. However, considering the complexity of the analysis and the large amount of spatial data necessary to accomplish that purpose, state of the art technological tools capable of processing multi-criteria analysis to support decision making are necessary. Thus, the current work developed for an area of 476 km² corresponding to the Una river watershed in the municipal district of Taubaté, SP, used a multi-criteria analysis based on the continuous classification and on Analytical Hierarchy Process (AHP paired comparisons techniques, available in the complete GIS package named SPRING (Georeferenced Information Processing System for generating a map of priority areas for the re-establishment of forest cover in that watershed. Results revealed a large area (26.6% of the entire watershed falling in the “Extreme Priority” class for forest cover re-establishment, what indicates the urgent need of environmental recovery of this basin considering that it is used for Taubaté city water supply. Results from this research support the decision making for resource optimization applied to priority areas in an operational way.

Subpixel Snow-covered Area Including Differentiated Grain Size from AVIRIS Data Over the Sierra Nevada Mountain Range

Science.gov (United States)

Hill, R.; Calvin, W. M.; Harpold, A. A.

2016-12-01

Mountain snow storage is the dominant source of water for humans and ecosystems in western North America. Consequently, the spatial distribution of snow-covered area is fundamental to both hydrological, ecological, and climate models. Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data were collected along the entire Sierra Nevada mountain range extending from north of Lake Tahoe to south of Mt. Whitney during the 2015 and 2016 snow-covered season. The AVIRIS dataset used in this experiment consists of 224 contiguous spectral channels with wavelengths ranging 400-2500 nanometers at a 15-meter spatial pixel size. Data from the Sierras were acquired on four days: 2/24/15 during a very low snow year, 3/24/16 near maximum snow accumulation, and 5/12/16 and 5/18/16 during snow ablation and snow loss. Previous retrieval of subpixel snow-covered area in alpine regions used multiple snow endmembers due to the sensitivity of snow spectral reflectance to grain size. We will present a model that analyzes multiple endmembers of varying snow grain size, vegetation, rock, and soil in segmented regions along the Sierra Nevada to determine snow-cover spatial extent, snow sub-pixel fraction and approximate grain size or melt state. The root mean squared error will provide a spectrum-wide assessment of the mixture model's goodness-of-fit. Analysis will compare snow-covered area and snow-cover depletion in the 2016 year, and annual variation from the 2015 year. Field data were also acquired on three days concurrent with the 2016 flights in the Sagehen Experimental Forest and will support ground validation of the airborne data set.

Low-cost computer classification of land cover in the Portland area, Oregon, by signature extension techniques

Science.gov (United States)

Gaydos, Leonard

1978-01-01

Computer-aided techniques for interpreting multispectral data acquired by Landsat offer economies in the mapping of land cover. Even so, the actual establishment of the statistical classes, or "signatures," is one of the relatively more costly operations involved. Analysts have therefore been seeking cost-saving signature extension techniques that would accept training data acquired for one time or place and apply them to another. Opportunities to extend signatures occur in preprocessing steps and in the classification steps that follow. In the present example, land cover classes were derived by the simplest and most direct form of signature extension: Classes statistically derived from a Landsat scene for the Puget Sound area, Wash., were applied to the Portland area, Oreg., using data for the next Landsat scene acquired less than 25 seconds down orbit. Many features can be recognized on the reduced-scale version of the Portland land cover map shown in this report, although no statistical assessment of its accuracy is available.

Vegetation cover and land use of a protected coastal area and its surroundings, southeast Brazil

OpenAIRE

Caris,Elisa Araujo Penna; Kurtz,Bruno Coutinho; Cruz,Carla Bernadete Madureira; Scarano,Fabio Rubio

2013-01-01

We applied remote sensing techniques on a TM Landsat 5 image (1:50,000) to map land use and vegetation cover of the Restinga de Jurubatiba National Park and surroundings. The thematic map generated from the digital classification of the image allowed us to spatially characterize and quantify the different land uses and soil covers of the area. Thirteen classes were identified. The most representative classes in the park were the Clusia (31.99%) and Ericaceae formations (29.14%). More than 90%...

Borders of left gastric lymph node area in 124 patients with esophageal and gastric cardia carcinoma

International Nuclear Information System (INIS)

Qian Pudong; Guo Yesong; Li Jianzhong; Wang Yufen; Feng Chunwei; Lv Hong; Fei Wenlong

2006-01-01

Objective: To measure and define the distribution of left gastric lymph nodes. Methods: From Jan. 2004 to Apr. 2005, silver clips were set around the root of the left gastric artery in 124 patients with esophageal and gastric cardia carcinoma, X-ray films at 0 degree and 90 degree simulator gantry in the radio- therapeutic position were taken. Then, the data of the superior, lower, left, right, anterior and posterior bor- der in each patient was recorded. With SAS 8.02 software, data of minimum area which covered the left gastric lymph node in different incidences were obtained. Results: According to the analysis of Shapiro-Wilk, Kolmogorov-Smimov, Cramervon Mises and Anderson-Darling tests, each border' was of normal distribution, with equal frequency in the male and female, despite the actual results in different genders. Pearson Correlation Coefficients analysis did not suggest a significant relationship between the border and height, weight and size of vertebrae, which formed the minimum area covering the left gastric area at frequency of 100%, 95%, 90% and 85%, which were drawn out through the calculation. Conclusions: Aiming at completely identifying the normal distribution of the left gastric lymph node, more patients are required to be in the pool. For the time being, location in the left gastric area can be obtained from details of the results in the present study. (authors)

Snow cover monitoring model and change over both time and space in pastoral area of northern China

Science.gov (United States)

Cui, Yan; Li, Suju; Wang, Ping; Zhang, Wei; Nie, Juan; Wen, Qi

2014-11-01

Snow disaster is a natural phenomenon owning to widespread snowfall for a long time and usually affect people's life, property and economic. During the whole disaster management circle, snow disaster in pastoral area of northern china which including Xinjiang, Inner Mongolia, Qinghai, Tibet has been paid more attention. Thus do a good job in snow cover monitoring then found snow disaster in time can help the people in disaster area to take effective rescue measures, which always been the central and local government great important work. Remote sensing has been used widely in snow cover monitoring for its wide range, high efficiency, less conditions, more methods and large information. NOAA/AVHRR data has been used for wide range, plenty bands information and timely acquired and act as an import data of Snow Cover Monitoring Model (SCMM). SCMM including functions list below: First after NOAA/AVHRR data has been acquired, geometric calibration, radiometric calibration and other pre-processing work has been operated. Second after band operation, four threshold conditions are used to extract snow spectrum information among water, cloud and other features in NOAA/AVHRR image. Third snow cover information has been analyzed one by one and the maximum snow cover from about twenty images in a week has been selected. Then selected image has been mosaic which covered the pastoral area of China. At last both time and space analysis has been carried out through this operational model ,such as analysis on the difference between this week and the same period of last year , this week and last week in three level regional. SCMM have been run successfully for three years, and the results have been take into account as one of the three factors which led to risk warning of snow disaster and analysis results from it always play an important role in disaster reduction and relief.

Land cover mapping with emphasis to burnt area delineation using co-orbital ALI and Landsat TM imagery

Science.gov (United States)

Petropoulos, George P.; Kontoes, Charalambos C.; Keramitsoglou, Iphigenia

2012-08-01

In this study, the potential of EO-1 Advanced Land Imager (ALI) radiometer for land cover and especially burnt area mapping from a single image analysis is investigated. Co-orbital imagery from the Landsat Thematic Mapper (TM) was also utilised for comparison purposes. Both images were acquired shortly after the suppression of a fire occurred during the summer of 2009 North-East of Athens, the capital of Greece. The Maximum Likelihood (ML), Artificial Neural Networks (ANNs) and Support Vector Machines (SVMs) classifiers were parameterised and subsequently applied to the acquired satellite datasets. Evaluation of the land use/cover mapping accuracy was based on the error matrix statistics. Also, the McNemar test was used to evaluate the statistical significance of the differences between the approaches tested. Derived burnt area estimates were validated against the operationally deployed Services and Applications For Emergency Response (SAFER) Burnt Scar Mapping service. All classifiers applied to either ALI or TM imagery proved flexible enough to map land cover and also to extract the burnt area from other land surface types. The highest total classification accuracy and burnt area detection capability was returned from the application of SVMs to ALI data. This was due to the SVMs ability to identify an optimal separating hyperplane for best classes' separation that was able to better utilise ALI's advanced technological characteristics in comparison to those of TM sensor. This study is to our knowledge the first of its kind, effectively demonstrating the benefits of the combined application of SVMs to ALI data further implying that ALI technology may prove highly valuable in mapping burnt areas and land use/cover if it is incorporated into the development of Landsat 8 mission, planned to be launched in the coming years.

The Effect Of Land Cover/Land Use On Groundwater Resources In Southern Egypt (Luxor Area): Remote Sensing And Field Studies

International Nuclear Information System (INIS)

Faid, A.M.; Hinz, E.A.; Montgomery, H.

2003-01-01

The impact of land cover/land use on groundwater can be critical. Land cover / land use maps give an early warning for planners and developers to protect groundwater resources from depletion and preserve its sustain ability. These land cover / land use maps can be used for the planning of groundwater development to prevent the deterioration of the aquifer. The Research Institute for Groundwater of Egypt (RIGW) has carried out hydrogeological studies in 1990 to evaluate the potentiality of groundwater in Luxor area in southern Egypt close to the Nile valley. The region is characterized by a rapid and continuous increase in land reclamation and development on the fringes which surround the already heavily cultivated land within the Nile valley. This presented a need for continuous monitoring and information updating over a vast region in a short time and at a reasonable cost. This study illustrates how remote sensing techniques can be effectively used for monitoring changes in land cover / land use in an effort to aid groundwater management. Landsat Thematic Mapper (TM) data collected in 1984 and 2000 were processed and analyzed over the study area to produce land cover/land use maps. The Normalized Difference Vegetation Index (NDVI) technique is used for Landsat TM images of to quantify areas which are covered by vegetation. Results indicated significant increase in cultivated areas. Remote sensing results are compared with iso-piezo metric maps and iso-salinity maps that were produced in 1984 and 2000. Comparison of these maps indicates groundwater depletion and salinity increase from 1984 to 2000. We relate this to the increase of the area being cultivated

BUILT-UP AREA AND LAND COVER EXTRACTION USING HIGH RESOLUTION PLEIADES SATELLITE IMAGERY FOR MIDRAND, IN GAUTENG PROVINCE, SOUTH AFRICA

Directory of Open Access Journals (Sweden)

E. Fundisi

2017-09-01

Full Text Available Urban areas, particularly in developing countries face immense challenges such as climate change, poverty, lack of resources poor land use management systems, and week environmental management practices. Mitigating against these challenges is often hampered by lack of data on urban expansion, urban footprint and land cover. To support the recently adopted new urban agenda 2030 there is need for the provision of information to support decision making in the urban areas. Earth observation has been identified as a tool to foster sustainable urban planning and smarter cities as recognized by the new urban agenda, because it is a solution to unavailability of data. Accordingly, this study uses high resolution EO data Pleiades satellite imagery to map and document land cover for the rapidly expanding area of Midrand in Johannesburg, South Africa. An unsupervised land cover classification of the Pleiades satellite imagery was carried out using ENVI software, whereas NDVI was derived using ArcGIS software. The land cover had an accuracy of 85% that is highly adequate to document the land cover in Midrand. The results are useful because it provides a highly accurate land cover and NDVI datasets at localised spatial scale that can be used to support land use management strategies within Midrand and the City of Johannesburg South Africa.

Built-Up Area and Land Cover Extraction Using High Resolution Pleiades Satellite Imagery for Midrand, in Gauteng Province, South Africa

Science.gov (United States)

Fundisi, E.; Musakwa, W.

2017-09-01

Urban areas, particularly in developing countries face immense challenges such as climate change, poverty, lack of resources poor land use management systems, and week environmental management practices. Mitigating against these challenges is often hampered by lack of data on urban expansion, urban footprint and land cover. To support the recently adopted new urban agenda 2030 there is need for the provision of information to support decision making in the urban areas. Earth observation has been identified as a tool to foster sustainable urban planning and smarter cities as recognized by the new urban agenda, because it is a solution to unavailability of data. Accordingly, this study uses high resolution EO data Pleiades satellite imagery to map and document land cover for the rapidly expanding area of Midrand in Johannesburg, South Africa. An unsupervised land cover classification of the Pleiades satellite imagery was carried out using ENVI software, whereas NDVI was derived using ArcGIS software. The land cover had an accuracy of 85% that is highly adequate to document the land cover in Midrand. The results are useful because it provides a highly accurate land cover and NDVI datasets at localised spatial scale that can be used to support land use management strategies within Midrand and the City of Johannesburg South Africa.

Partial pleural covering for intractable pneumothorax in patients with Birt-Hogg-Dubé Syndrome.

Science.gov (United States)

Okada, Akira; Hirono, Tatsuhiko; Watanabe, Takehiro; Hasegawa, Go; Tanaka, Reiko; Furuya, Mitsuko

2017-03-01

Birt-Hogg-Dubé syndrome (BHD) is an inherited disorder associated with a germline mutation of the folliculin (FLCN) gene. Most patients with BHD have multiple pulmonary cysts, and are at high risk of repeated pneumothorax. Although an increasing number of patients are diagnosed with BHD by genetic testing, therapeutic approaches for intractable pneumothorax have not yet been described. We treated three patients who had repeated episodes of pneumothorax. All had multiple pulmonary cysts in the lower lobes, and two had a family history of pneumothorax. Video-assisted thoracic surgery was used to perform wedge resections and partial pleural covering of the cystic lesions. The partial pleural covering technique used sheets of polyglycolic acid felt or regenerative oxidized cellulose mesh. The resected tissues underwent histopathological evaluation, and peripheral blood leukocytes were tested for FLCN mutations. The operative times were less than 2 h, and there were no complications. The resected cysts had histopathological features characteristic of BHD lung. All patients were found to have FLCN germline mutations; thus their repeated pneumothoraces were a manifestation of BHD. None of the patients developed respiratory problems after undergoing the partial pleural covering procedure, and they have all been well without pneumothorax for 30 months or more. Partial pleural covering combined with resection of protruding cysts should be a safe and effective therapeutic approach for BHD patients with intractable pneumothorax. Further investigation is needed to establish a detailed protocol for treatment of pneumothorax that results in minimal functional impairment. © 2015 John Wiley & Sons Ltd.

Paravertebral and Brachial plexus block for Abdominal flap to cover the upper limb wound

Directory of Open Access Journals (Sweden)

Narendra kumar

2011-08-01

Full Text Available We present a case report where thoracic paravertebral block and brachial plexus block were used in a sick elderly patient with poor cardiopulmonary reserve, to cover a post traumatic raw area of the upper limb by raising flap from lateral abdominal wall. The residual raw area of abdomen was then covered with the split skin graft taken from thigh.

Solar radiation measurements and Leaf Area Index (LAI) from vegetal covers

International Nuclear Information System (INIS)

Wandelli, E.V.; Marques Filho, A. de O.

1999-01-01

A method by which a physical model of the solar radiation transfer in a vegetal medium is inverted to estimate the leaf area index (LAI) for different types of vegetation is presented here, as an alternative to the destructive experiments, which are a hard task to implement on the vegetation covers. Radiation data were obtained during the dry season — 1996, at the Embrapa Experimental Station, (BR 174 - km 54, 2° 31' S, 60° 01' W), Manaus, Brazil. The method yielded convergent values for the LAI between different adopted radiation classes with more stable estimates at time when there is a predominant diffuse radiation. The application of the inversion algorithm yields the following values for the leaf area index and respective annual foliage increments: 3.5 (0.35 yr. -1 ) for the intact secondary forest; 2.0 (0.5 yr -1 ) for the palm agroforestry system; and 1.6 (0.4 yr -1 ) for the multi-layer ones [pt

Study Of Land Cover And Condition Catchment Area Groundwater Aquifer In Tanah Merah North Samarinda District Using Resistivity Geoelectric Sounding

Directory of Open Access Journals (Sweden)

Djayus

2017-06-01

Full Text Available Land cover is a biophysical cover that maintains land conditions in water balance. The purpose of this research is to know the condition of land cover water catchment groundwater aquifer and correlation. This research begins by collecting data on land cover soil type rainfall slopes and groundwaterinformation. Field activities include observation and data collection of land cover geological conditions community wells and geoelectric sounding. Land cover data is classified according to circumstances and conditions. Geoelectric sounding data was analyzed with IP2WIN software interpretation of lithologic variation of rocks and depth based on resistivity value. Plot the position of each lithology sounding with Surfer software obtained kontour rock field boundary and 3D model of the aquifer position.The results showed that the land cover consisted of vegetated areas forests 27221 Ha 4032 and agricultural land 18336 Ha 2716 non-vegetation area 9880 Ha 1464 constructed land Open land 116.33 Ha 17.23 and water body 4.35 Ha 0.64 The condition of land cover in this water catchment area has decreased 6838 Ha 1014 from the previous condition 34059 Ha 5046 to 27221 Ha 4032. Referring to Permenhut RI No. 32 in 2009 total score catchment area 33 including the somewhat critical condition. Groundwater aquifers based on 3D sounding geolistrik modeling consist of a free aquifer for shallow groundwater depth of water level between 2-30 m with thickness 2-65 m and a distorted aquifer for groundwaterin depth of water between 75-150 m With thickness 75-125 m depth of community well 10-45 m. The transfer of land into open pit mines resulted in the destruction of the balance and water system the decreasing decreasing the discharge of the well water of the community drill the failure and the lack of new water discharge of the new wells the loss of groundwaterin several dug wells landslides and mud floods on the farmland

Land Cover Mapping using GEOBIA to Estimate Loss of Salacca zalacca Trees in Landslide Area of Clapar, Madukara District of Banjarnegara

Science.gov (United States)

Permata, Anggi; Juniansah, Anwar; Nurcahyati, Eka; Dimas Afrizal, Mousafi; Adnan Shafry Untoro, Muhammad; Arifatha, Na'ima; Ramadhani Yudha Adiwijaya, Raden; Farda, Nur Mohammad

2016-11-01

Landslide is an unpredictable natural disaster which commonly happens in highslope area. Aerial photography in small format is one of acquisition method that can reach and obtain high resolution spatial data faster than other methods, and provide data such as orthomosaic and Digital Surface Model (DSM). The study area contained landslide area in Clapar, Madukara District of Banjarnegara. Aerial photographs of landslide area provided advantage in objects visibility. Object's characters such as shape, size, and texture were clearly seen, therefore GEOBIA (Geography Object Based Image Analysis) was compatible as method for classifying land cover in study area. Dissimilar with PPA (PerPixel Analyst) method that used spectral information as base object detection, GEOBIA could use spatial elements as classification basis to establish a land cover map with better accuracy. GEOBIA method used classification hierarchy to divide post disaster land cover into three main objects: vegetation, landslide/soil, and building. Those three were required to obtain more detailed information that can be used in estimating loss caused by landslide and establishing land cover map in landslide area. Estimating loss in landslide area related to damage in Salak (Salacca zalacca) plantations. This estimation towards quantity of Salak tree that were drifted away by landslide was calculated in assumption that every tree damaged by landslide had same age and production class with other tree that weren't damaged. Loss calculation was done by approximating quantity of damaged trees in landslide area with data of trees around area that were acquired from GEOBIA classification method.

Monitoring land use/land cover transformations from 1945 to 2007 in two peri-urban mountainous areas of Athens metropolitan area, Greece.

Science.gov (United States)

Mallinis, Giorgos; Koutsias, Nikos; Arianoutsou, Margarita

2014-08-15

The aims of this study were to map and analyze land use/land cover transitions and landscape changes in the Parnitha and Penteli mountains, which surround the Athens metropolitan area of Attica, Greece over a period of 62 years. In order to quantify the changes between land categories through time, we computed the transition matrices for three distinct periods (1945-1960, 1960-1996, and 1996-2007), on the basis of available aerial photographs used to create multi-temporal maps. We identified systematic and stationary transitions with multi-level intensity analysis. Forest areas in Parnitha remained the dominant class of land cover throughout the 62 years studied, while transitional woodlands and shrublands were the main classes involved in LULC transitions. Conversely, in Penteli, transitional woodlands, along with shrublands, dominated the study site. The annual rate of change was faster in the first and third time intervals, compared to the second (1960-1996) time interval, in both study areas. The category level analysis results indicated that in both sites annual crops avoided to gain while discontinuous urban fabric avoided to lose areas. At the transition level of analysis, similarities as well as distinct differences existed between the two areas. In both sites the gaining pattern of permanent crops with respect to annual crops and the gain of forest with respect to transitional woodland/shrublands were stationary across the three time intervals. Overall, we identified more systematic transitions and stationary processes in Penteli. We discussed these LULC changes and associated them with human interference (activity) and other major socio-economic developments that were simultaneously occurring in the area. The different patterns of change of the areas, despite their geographical proximity, throughout the period of analysis imply that site-specific studies are needed in order to comprehensively assess the driving forces and develop models of landscape

Effect of Cover Crops on Vertical Distribution of Leaf Area and Dry Matter of Soybean (Glycine max L. in Competition with Weeds

Directory of Open Access Journals (Sweden)

seyyedeh samaneh hashemi

2017-08-01

Full Text Available Introduction Amount and vertical distribution of leaf area are essential for estimating interception and utilization of solar radiation of crop canopies and, consequently dry matter accumulation (Valentinuz & Tollenaar, 2006. Vertical distribution of leaf area is leaf areas per horizontal layers, based on height (Boedhram et al., 2001. Above-ground biomass is one of the central traits in functional plant ecology and growth analysis. It is a key parameter in many allometric relationships (Niklas & Enquist, 2002. The vertical biomass distribution is considered to be the main determinant of competitive strength in plant species. The presence of weeds intensifies competition for light, with the effect being determined by plant height, position of the branches, and location of the maximum leaf area. So, this experiment was conducted to study the vertical distribution of leaf area and dry matter of soybean canopy in competition with weeds and cover crops. Materials and methods This experiment was performed based on complete randomized block design with 3 replications in center of Agriculture of Joybar in 2013. Soybean was considered as main crop and soybean and Persian clover (Trifolium resupinatum L., fenugreek (Trigonella foenum–graecum L., chickling pea (Lathyrus sativus L. and winter vetch (Vicia sativa L. were the cover crops. Treatments were included cover crops (Persian clover, fenugreek, chickling pea and winter vetch and cover crop planting times (simultaneous planting of soybean with cover crops and planting cover crops three weeks after planting of soybeans and also monoculture of soybeans both in weedy and weed free conditions were considered as controls. Soybean planted in 50 cm row spacing with 5 cm between plants in the same row. Each plot was included 5 rows soybeans. Cover crop inter-seeded simultaneously in the main crop. Crops were planted on 19 May 2013 for simultaneous planting of soybean. The dominant weed species were green

Evaluation of impermeable covers for bedding in patients with allergic rhinitis

NARCIS (Netherlands)

Terreehorst, Ingrid; Hak, Eelko; Oosting, Albert J.; Tempels-Pavlica, Zana; de Monchy, Jan G. R.; Bruijnzeel-Koomen, Carla A. F. M.; Aalberse, Rob C.; Gerth van Wijk, Roy

2003-01-01

BACKGROUND: Encasing bedding in impermeable covers reduces exposure to house-dust mites, but the clinical benefit of this intervention as part of mite-avoidance measures for patients with allergic rhinitis is not known. We performed a multicenter, randomized, placebo-controlled trial of one year of

A Fast Placement Technique for Covered Tracheobronchial Stents in Patients with Complicated Esophagorespiratory Fistulas

International Nuclear Information System (INIS)

Kishi, Kazushi; Nakao, Taisei; Goto, Hironobu; Kimura, Masashi; Sonomura, Tetsuo; Yamanaka, Noboru; Nanjo, Kishio; Sato, Morio

2005-01-01

Purpose. To test an endotracheal placement procedure for malignant esophagorespiratory fistula when endoesophageal placement is inapplicable. Methods. We report on patients with malignant esophagorespiratory fistula to which endoesophageal approaches were complicated with a complete obstruction of the hypopharynx, a collapsible tracheobronchus, or a previously placed endoesophageal stents. Gore-Tex membrane-covered Z-stents were deployed in the trachea using a coaxial introducer system in three patients. A Dumon tube was deployed in the bronchus over the bronchofiberscope in one patient. Results. All fistula were completely sealed by the endotracheal or endobronchial stenting. Symptomatic and clinical improvements were immediate obtained. Conclusion. Endotracheal or endobronchial covered stent placement is thought to be an effective alternative method for sealing esophagorespiratory fistula

High spatial resolution mapping of land cover types in a priority area for conservation in the Brazilian savanna

Science.gov (United States)

Ribeiro, F.; Roberts, D. A.; Hess, L. L.; Davis, F. W.; Caylor, K. K.; Nackoney, J.; Antunes Daldegan, G.

2017-12-01

Savannas are heterogeneous landscapes consisting of highly mixed land cover types that lack clear distinct boundaries. The Brazilian Cerrado is a Neotropical savanna considered a biodiversity hotspot for conservation due to its biodiversity richness and rapid transformation of its landscape by crop and pasture activities. The Cerrado is one of the most threatened Brazilian biomes and only 2.2% of its original extent is strictly protected. Accurate mapping and monitoring of its ecosystems and adjacent land use are important to select areas for conservation and to improve our understanding of the dynamics in this biome. Land cover mapping of savannas is difficult due to spectral similarity between land cover types resulting from similar vegetation structure, floristically similar components, generalization of land cover classes, and heterogeneity usually expressed as small patch sizes within the natural landscape. These factors are the major contributor to misclassification and low map accuracies among remote sensing studies in savannas. Specific challenges to map the Cerrado's land cover types are related to the spectral similarity between classes of land use and natural vegetation, such as natural grassland vs. cultivated pasture, and forest ecosystem vs. crops. This study seeks to classify and evaluate the land cover patterns across an area ranked as having extremely high priority for future conservation in the Cerrado. The main objective of this study is to identify the representativeness of each vegetation type across the landscape using high to moderate spatial resolution imagery using an automated scheme. A combination of pixel-based and object-based approaches were tested using RapidEye 3A imagery (5m spatial resolution) to classify the Cerrado's major land cover types. The random forest classifier was used to map the major ecosystems present across the area, and demonstrated to have an effective result with 68% of overall accuracy. Post

EVALUATION OF DATA APPLICABILITY FOR D-INSAR IN AREAS COVERED BY ABUNDANT VEGETATION

Directory of Open Access Journals (Sweden)

P. Zhang

2018-04-01

Full Text Available In the past few years, the frequent geological disasters have caused enormous casualties and economic losses. Therefore, D-InSAR (differential interferometry synthetic aperture radar has been widely used in early-warning and post disaster assessment. However, large area of decorrelation often occurs in the areas covered with abundant vegetation, which seriously affects the accuracy of surface deformation monitoring. In this paper, we analysed the effect of sensor parameters and external environment parameters on special decorrelation. Then Synthetic Aperture Radar (SAR datasets acquired by X-band TerraSAR-X, Phased Array type L-band Synthetic Aperture Satellite-2 (ALOS-2, and C-band Sentinel-1 in Guizhou province were collected and analysed to generate the maps of coherence, which were used to evaluating the applicability of datasets of different wavelengths for D-InSAR in forest area. Finally, we found that datasets acquired by ALOS-2 had the best monitoring effect.

Land use/ land cover and ecosystem functions change in the grassland restoration program areas in China from 2000 to 2010

Science.gov (United States)

Zhang, H.; Fan, J.

2015-12-01

The grassland restoration areas in China, most of which was located in arid and semi-arid areas, are affected by climate change and anthropogenic activities. Using the 3S (RS, GIS, GPS) technologies, quantitative analysis method of landscape patterns and ecological simulation, this study examines the spatiotemporal characteristics of land use/ land cover and ecosystem functions change in the grassland restoration areas in China from 2000 to 2010. We apply two parameters land use transfer matrix and land use dynamic degree to explore the speed and regional differentiation of land use change. We propose vegetation coverage, net primary production (NPP), soil and water conservation capacity to assess the ecosystem functions. This study analyzes the characteristics of landscape patterns at the class and landscape levels and explores the ecological effect of land use pattern and regional ecological processes. The results show that: (1) Grassland and others were the main landscape types in the study area in the past decade. The ecosystem structure was stable. About 0.37% of the total grassland area in 2000 experienced change in land use / land cover types. The area of woodlands, wetlands, farmlands, and built-up areas expanded. The area of others has declined. (2) The dynamic degree of regional land use was less than one percent in the recent ten years. The speed of land use and land cover change was low, and regional differentiation of change between the provinces was small. (3) The matrix of the landscape did not change in the study area. Landscape fragmentation index values decreased progressively; landscape diversity rose continuously; landscape aggregation and continuity decreased slightly; the landscape maintained relative integrity. (4) Ecosystem functions has increased as a whole. The vegetation coverages with significant increase (with a 1.99% yr-1 slope of regression) in the total study area; NPP has a fluctuating and increasing tendency, ranging from 218.23 g

Hydrological Modelling and data assimilation of Satellite Snow Cover Area using a Land Surface Model, VIC

Directory of Open Access Journals (Sweden)

S. Naha

2016-06-01

Full Text Available The snow cover plays an important role in Himalayan region as it contributes a useful amount to the river discharge. So, besides estimating rainfall runoff, proper assessment of snowmelt runoff for efficient management and water resources planning is also required. A Land Surface Model, VIC (Variable Infiltration Capacity is used at a high resolution grid size of 1 km. Beas river basin up to Thalot in North West Himalayas (NWH have been selected as the study area. At first model setup is done and VIC has been run in its energy balance mode. The fluxes obtained from VIC has been routed to simulate the discharge for the time period of (2003-2006. Data Assimilation is done for the year 2006 and the techniques of Data Assimilation considered in this study are Direct Insertion (D.I and Ensemble Kalman Filter (EnKF that uses observations of snow covered area (SCA to update hydrologic model states. The meteorological forcings were taken from 0.5 deg. resolution VIC global forcing data from 1979-2006 with daily maximum temperature, minimum temperature from Climate Research unit (CRU, rainfall from daily variability of NCEP and wind speed from NCEP-NCAR analysis as main inputs and Indian Meteorological Department (IMD data of 0.25 °. NBSSLUP soil map and land use land cover map of ISRO-GBP project for year 2014 were used for generating the soil parameters and vegetation parameters respectively. The threshold temperature i.e. the minimum rain temperature is -0.5°C and maximum snow temperature is about +0.5°C at which VIC can generate snow fluxes. Hydrological simulations were done using both NCEP and IMD based meteorological Forcing datasets, but very few snow fluxes were obtained using IMD data met forcing, whereas NCEP based met forcing has given significantly better snow fluxes throughout the simulation years as the temperature resolution as given by IMD data is 0.5°C and rainfall resolution of 0.25°C. The simulated discharge has been validated

[Covering stoma in anterior rectum resection with TME for rectal cancer in elderly patients].

Science.gov (United States)

Cirocchi, Roberto; Grassi, Veronica; Barillaro, Ivan; Cacurri, Alban; Koltraka, Bledar; Coccette, Marco; Sciannameo, Francesco

2010-01-01

The aim of our study is to evaluate the advisability of covering stoma in Anterior Rectum Resection with TME in elderly patients. A research of both the Ministry of Health and Terni Hospital databases has been conducted so as to collect information about patients with rectal tumor. Such research allowed to identify the amount of patients diagnosed with rectal cancer, the type of intervention, and the average hospitalization time. Between January 1997 and June 2008, 209 patients have undergone chirurgical surgery at Terni hospital's General and Emergency Surgical Clinic. An Anterior Rectum Resection with TME has been performed in 135 patients out of the sample (64.59%). The average hospitalization time of geriatric patients does not show significant differences compared to that of younger patients. An age-cohort analysis has been performed among patients who have been subject to stomia and those who have not. The former have been further split up between those who underwent ileostomy and those subject to colostomy. While ileostomy patients face a similar hospitalization time across all age cohorts, geriatric colostomy patients face longer hospitalizations than younger patients. Patients subject to Anterior Rectum Resection show no meaningful differences, in terms of hospitalization time, across all age cohorts. In geriatric patients the construction of covering stoma has resulted in longer hospitalizations only when a loop colostomy was executed, as opposed to loop ileostomy.

Dust pollution of snow cover in the industrial areas of Tomsk city (Western Siberia, Russia)

Science.gov (United States)

Talovskaya, A. V.; Filimonenko, E. A.; Osipova, N. A.; Yazikov, E. G.; Nadeina, L. V.

2016-03-01

This article describes the results of long-term monitoring (2007-2014) of snow cover pollution in the territory of Tomsk city. Snow samples were collected in the territory of Tomsk. Determination of dust load level was carried out by comparing with the background and reference values. It has been determined that the north-east and central parts of Tomsk are the most contaminated areas, where brickworks, coal and gas-fired thermal power plant are located. The analysis of long-term dynamics showed a dust load decrease in the vicinity of coal and gas-fired thermal power plant due to upgrading of the existing dust collecting systems. During the monitoring period the high dust load in the vicinity of brickworks did not change. The lowest value of the dust load on snow cover was detected in the vicinity of the petrochemical plant and concrete product plants. The near and far zones of dust load on snow cover were determined with the reference to the location of the studied plants.

Characterization Report Operational Closure Covers for the Area 5 Radioactive Waste Management Site at the Nevada Test Site

International Nuclear Information System (INIS)

Bechtel Nevada Geotechnical Sciences

2005-01-01

Bechtel Nevada (BN) manages two low-level Radioactive Waste Management Sites (RWMSs) at the Nevada Test Site (NTS) for the U.S. Department of Energy (DOE) National Nuclear Security Administration Nevada Site Office (NNSA/NSO). The Area 3 RWMS is located in south-central Yucca Flat and the Area 5 RWMS is located about 15 miles south, in north-central Frenchman Flat. Though located in two separate topographically closed basins, they are similar in climate and hydrogeologic setting. The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste, while the Area 3 RWMS uses subsidence craters formed from underground testing of nuclear weapons for the disposal of packaged and unpackaged bulk waste. Over the next several decades, most waste disposal units at both the Area 3 and Area 5 RWMSs are anticipated to be closed. Closure of the Area 3 and Area 5 RWMSs will proceed through three phases: operational closure, final closure, and institutional control. Many waste disposal units at the Area 5RWMS are operationally closed and final closure has been placed on one unit at the Area 3 RWMS (U-3ax/bl). Because of the similarities between the two sites (e.g., type of wastes, environmental factors, operational closure cover designs, etc.), many characterization studies and data collected at the Area 3 RWMS are relevant and applicable to the Area 5 RWMS. For this reason, data and closure strategies from the Area 3 RWMS are referred to as applicable. This document is an interim Characterization Report - Operational Closure Covers, for the Area 5 RWMS. The report briefly describes the Area 5 RWMS and the physical environment where it is located, identifies the regulatory requirements, reviews the approach and schedule for closing, summarizes the monitoring programs, summarizes characterization studies and results, and then presents conclusions and recommendations

Palliation of patients with esophagogastric neoplasms by insertion of a covered expandable modified Gianturco-Z endoprosthesis: experiences in 153 patients

NARCIS (Netherlands)

Bartelsman, J. F.; Bruno, M. J.; Jensema, A. J.; Haringsma, J.; Reeders, J. W.; Tytgat, G. N.

2000-01-01

We aimed to evaluate the short- and long-term outcomes of treatment by insertion of a covered expandable modified Gianturco-Z endoprosthesis (Song stent) in patients with esophagogastric malignancies. Consecutive patients with esophagogastric malignancies in whom a Song stent was inserted were

Updating the 2001 National Land Cover Database land cover classification to 2006 by using Landsat imagery change detection methods

Science.gov (United States)

Xian, George; Homer, Collin G.; Fry, Joyce

2009-01-01

The recent release of the U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001, which represents the nation's land cover status based on a nominal date of 2001, is widely used as a baseline for national land cover conditions. To enable the updating of this land cover information in a consistent and continuous manner, a prototype method was developed to update land cover by an individual Landsat path and row. This method updates NLCD 2001 to a nominal date of 2006 by using both Landsat imagery and data from NLCD 2001 as the baseline. Pairs of Landsat scenes in the same season in 2001 and 2006 were acquired according to satellite paths and rows and normalized to allow calculation of change vectors between the two dates. Conservative thresholds based on Anderson Level I land cover classes were used to segregate the change vectors and determine areas of change and no-change. Once change areas had been identified, land cover classifications at the full NLCD resolution for 2006 areas of change were completed by sampling from NLCD 2001 in unchanged areas. Methods were developed and tested across five Landsat path/row study sites that contain several metropolitan areas including Seattle, Washington; San Diego, California; Sioux Falls, South Dakota; Jackson, Mississippi; and Manchester, New Hampshire. Results from the five study areas show that the vast majority of land cover change was captured and updated with overall land cover classification accuracies of 78.32%, 87.5%, 88.57%, 78.36%, and 83.33% for these areas. The method optimizes mapping efficiency and has the potential to provide users a flexible method to generate updated land cover at national and regional scales by using NLCD 2001 as the baseline.

Assessment of the vegetation cover in a burned area 22-years ago using remote sensing techniques and GIS analysis (Sierra de las Nieves, South of Spain).

Science.gov (United States)

Martínez-Murillo, Juan F.; Remond, Ricardo; Ruiz-Sinoga, José D.

2015-04-01

The study aim was to characterize the vegetation cover in a burned area 22-years ago considering the previous situation to wildfire in 1991 and the current one in 2013. The objectives were to: (i) compare the current and previous vegetation cover to widlfire; (ii) evaluate whether the current vegetation has recovered the previous cover to wildfire; and (iii) determine the spatial variability of vegetation recovery after 22-years since the wildfire. The study area is located in Sierra de las Nieves, South of Spain. It corresponds to an area affected by a wildfire in August 8th, 1991. The burned area was equal to 8156 ha. The burn severity was spatially very high. The main geographic features of the burned area are: mountainous topography (altitudes ranging from 250 m to 1500 m; slope gradient >25%; exposure mainly southfacing); igneous (peridotites), metamorphic (gneiss) and calcareous rocks (limestones); and predominant forest land use (Pinus pinaster sp. woodlands, 10%; pinus opened forest + shrubland, 40%; shrubland, 35%; and bare soil + grassland, 15%). Remote sensing techniques and GIS analysis has been applied to achieve the objectives. Landsat 5 and Landsat 8 images were used: July 13th, 1991 and July 1st, 2013, for the previous wildfire situation and 22-years after, respectively. The 1990 CORINE land cover was also considered to map 1991 land uses prior the wildfire. Likewise, the Andalucía Regional Government wildfire historic records were used to select the burned area and its geographical limit. 1991 and 2013 land cover map were obtained by means of object-oriented classifications. Also, NDVI and PVI1 vegetation indexes were calculated and mapped for both years. Finally, some images transformations and kernel density images were applied to determine the most recovered areas and to map the spatial concentration of bare soil and pine cover areas in 1991 and 2013, respectively. According to the results, the combination of remote sensing and GIS analysis let

Esprit HR mattress cover in pressure ulcer prevention.

Science.gov (United States)

Khoulowa, J

Modern mattresses provide soft dense foam, which permits the redistribution of pressure on the patient over a wider area - away from bony prominences where pressure ulcers usually occur. The material used in producing multistretch covers for the new mattresses had a tendency to delaminate as a result of a combination of heat, moisture and inappropriate cleansing techniques causing the water barriers to fall. In partnership with York Health NHS Trust and the material manufacturer, STM Healthcare produced a mattress cover (Esprit HR) which was able to withstand higher pressure from heat and moisture and greatly extended the life expectancy of the Esprit HR mattress.

Variability of snow line elevation, snow cover area and depletion in the main Slovak basins in winters 2001–2014

Directory of Open Access Journals (Sweden)

Krajčí Pavel

2016-03-01

Full Text Available Spatial and temporal variability of snow line (SL elevation, snow cover area (SCA and depletion (SCD in winters 2001–2014 is investigated in ten main Slovak river basins (the Western Carpathians. Daily satellite snow cover maps from MODIS Terra (MOD10A1, V005 and Aqua (MYD10A1, V005 with resolution 500 m are used.

Landfill Top Covers

DEFF Research Database (Denmark)

Scheutz, Charlotte; Kjeldsen, Peter

2011-01-01

The purpose of the final cover of a landfill is to contain the waste and to provide for a physical separation between the waste and the environment for protection of public health. Most landfill covers are designed with the primary goal to reduce or prevent infiltration of precipitation...... into the landfill in order to minimize leachate generation. In addition the cover also has to control the release of gases produced in the landfill so the gas can be ventilated, collected and utilized, or oxidized in situ. The landfill cover should also minimize erosion and support vegetation. Finally the cover...... is landscaped in order to fit into the surrounding area/environment or meet specific plans for the final use of the landfill. To fulfill the above listed requirements landfill covers are often multicomponent systems which are placed directly on top of the waste. The top cover may be placed immediately after...

Digital Cover Photography for Estimating Leaf Area Index (LAI in Apple Trees Using a Variable Light Extinction Coefficient

Directory of Open Access Journals (Sweden)

Carlos Poblete-Echeverría

2015-01-01

Full Text Available Leaf area index (LAI is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io and transmitted radiation (I through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAID, which was compared with LAI estimated by the proposed digital photography method (LAIM. Results showed that the LAIM was able to estimate LAID with an error of 25% using a constant light extinction coefficient (k = 0.68. However, when k was estimated using an exponential function based on the fraction of foliage cover (ff derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions.

Digital cover photography for estimating leaf area index (LAI) in apple trees using a variable light extinction coefficient.

Science.gov (United States)

Poblete-Echeverría, Carlos; Fuentes, Sigfredo; Ortega-Farias, Samuel; Gonzalez-Talice, Jaime; Yuri, Jose Antonio

2015-01-28

Leaf area index (LAI) is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io) and transmitted radiation (I) through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAI(D)), which was compared with LAI estimated by the proposed digital photography method (LAI(M)). Results showed that the LAI(M) was able to estimate LAI(D) with an error of 25% using a constant light extinction coefficient (k = 0.68). However, when k was estimated using an exponential function based on the fraction of foliage cover (f(f)) derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic) were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions.

Digital Cover Photography for Estimating Leaf Area Index (LAI) in Apple Trees Using a Variable Light Extinction Coefficient

Science.gov (United States)

Poblete-Echeverría, Carlos; Fuentes, Sigfredo; Ortega-Farias, Samuel; Gonzalez-Talice, Jaime; Yuri, Jose Antonio

2015-01-01

Leaf area index (LAI) is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io) and transmitted radiation (I) through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAID), which was compared with LAI estimated by the proposed digital photography method (LAIM). Results showed that the LAIM was able to estimate LAID with an error of 25% using a constant light extinction coefficient (k = 0.68). However, when k was estimated using an exponential function based on the fraction of foliage cover (ff) derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic) were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions. PMID:25635411

Habitat Characteristics of Bracken-Covered Areas Intended for Afforestation in Ličko Sredogorje

Directory of Open Access Journals (Sweden)

Zvonko Seletković

2013-12-01

Full Text Available Background and Purpose: Forest cultures in continental part of Croatia are mainly based on bracken-covered areas and moors on deserted agriculture soils and pastures. Successful afforestation i.e. establishment of forest cultures depends among other things on the understanding of habitats and ecology of forest trees. The choice of best species of forest trees for afforestation needs to be based on the research in soil and climate characteristics of target habitats. The aims of this research were to show mesoclimatic characteristics of Ličko sredogorje and microclimatic and pedological characteristics of Ličko polje. Also, based on habitat characteristics and ecology of forest trees, the aim was to determine species of forest trees suitable for afforestation of bracken-covered areas. Materials and Methods: Climate, microclimate, pedological and plant nutrition researches were done at the area of Lika highlands. Climate analysis was done according to air temperatures, amount of precipitation, relative air humidity and other climate elements and appearances. Composite soil samples were taken from the depth of 0-30 cm in order to determine plant nutrition potential. Samples were prepared for further analysis in the laboratory. Results: The highest average annual air temperature of 9.6 °C was found at weather station Gračac and the lowest at Korenica station (8.1 °C. Average amount of precipitation for this region was around 1500 mm. Monthly rain factors were ranging from arid to perhumid. Considering thermal character of the climate, the area has moderately warm climate. Average volumetric soil humidity is 14.2 %. Soil has strong acid reaction, is very humus, good to richly supplied with total nitrogen, content of physiologically active phosphorus and potassium is low, and C/N ration normal. Conclusions: According to habitat characteristics in the area of Ličko sredogorje and ecological demands of forest tree species, forest cultures of Common

Conversion of traditional agricultural land to built-up areas. Land use/cover changes in the municipality of Valencia (1956-2012

Directory of Open Access Journals (Sweden)

Antonio Valera Lozano

2017-01-01

Full Text Available The aim of this study is to understand the land use-cover dynamics from the mid- 1950s to 2012 in the municipality of Valencia, eastern Spain. The study area is a very interesting example of the many land use and land cover changes in the landscape of Mediterranean alluvial plains. The analysis was based on photo interpretation of aerial photographs (1956, 1984, 2006 and 2012 and GIS based methodology. At a detailed scale (1:10,000, results show that there has been a highly dynamic process produced by the extent of land developed as urban area. In 1956 11,112 hectares were occupied by agricultural land and natural areas. During fifty five years, the sealed surface was 2,396 hectares. In 2012 the built-up extent was around 33% of the studied area. In the municipality of Valencia much of the land converted to urban use was once highly productive agricultural land.

Multitemporal analysis of Landsat images to detect land use land cover changes for monitoring soil sealing in the Nola area (Naples, Italy)

Science.gov (United States)

De Giglio, Michaela; Allocca, Maria; Franci, Francesca

2016-10-01

Land Use Land Cover Changes (LULCC) data provide objective information to support environmental policy, urban planning purposes and sustainable land development. Understanding of past land use/cover practices and current landscape patterns is critical to assess the effects of LULCC on the Earth system. Within the framework of soil sealing in Italy, the present study aims to assess the LULCC of the Nola area (Naples metropolitan area, Italy), relating to a thirty year period from 1984 to 2015. The urban sprawl affects this area causing the impervious surface increase, the loss in rural areas and landscape fragmentation. Located near Vesuvio volcano and crossed by artificial filled rivers, the study area is subject to landslide, hydraulic and volcanic risks. Landsat time series has been processed by means of the supervised per-pixel classification in order to produce multitemporal Land Use Land Cover maps. Then, post-classification comparison approach has been applied to quantify the changes occurring between 1984 and 2015, also analyzing the intermediate variations in 1999, namely every fifteen years. The results confirm the urban sprawl. The increase of the built-up areas mainly causes the habitat fragmentation and the agricultural land conversion of the Nola area that is already damaged by unauthorized disposal of urban waste. Moreover, considering the local risk maps, it was verified that some of the new urban areas were built over known hazardous sites. In order to limit the soil sealing, urgent measures and sustainable urban planning are required.

Land-cover mapping of Red Rock Canyon National Conservation Area and Coyote Springs, Piute-Eldorado Valley, and Mormon Mesa Areas of Critical Environmental Concern, Clark County, Nevada

Science.gov (United States)

Smith, J. LaRue; Damar, Nancy A.; Charlet, David A.; Westenburg, Craig L.

2014-01-01

DigitalGlobe’s QuickBird satellite high-resolution multispectral imagery was classified by using Visual Learning Systems’ Feature Analyst feature extraction software to produce land-cover data sets for the Red Rock Canyon National Conservation Area and the Coyote Springs, Piute-Eldorado Valley, and Mormon Mesa Areas of Critical Environmental Concern in Clark County, Nevada. Over 1,000 vegetation field samples were collected at the stand level. The field samples were classified to the National Vegetation Classification Standard, Version 2 hierarchy at the alliance level and above. Feature extraction models were developed for vegetation on the basis of the spectral and spatial characteristics of selected field samples by using the Feature Analyst hierarchical learning process. Individual model results were merged to create one data set for the Red Rock Canyon National Conservation Area and one for each of the Areas of Critical Environmental Concern. Field sample points and photographs were used to validate and update the data set after model results were merged. Non-vegetation data layers, such as roads and disturbed areas, were delineated from the imagery and added to the final data sets. The resulting land-cover data sets are significantly more detailed than previously were available, both in resolution and in vegetation classes.

A Novel Partially Covered Self-Expandable Metallic Stent with Proximal Flare in Patients with Malignant Gastric Outlet Obstruction.

Science.gov (United States)

Takahara, Naminatsu; Isayama, Hiroyuki; Nakai, Yousuke; Yoshida, Shuntaro; Saito, Tomotaka; Mizuno, Suguru; Yagioka, Hiroshi; Kogure, Hirofumi; Togawa, Osamu; Matsubara, Saburo; Ito, Yukiko; Yamamoto, Natsuyo; Tada, Minoru; Koike, Kazuhiko

2017-07-15

Endoscopic placement of self-expandable metal stents (SEMSs) has emerged as a palliative treatment for malignant gastric outlet obstruction (GOO). Although covered SEMSs can prevent tumor ingrowth, frequent migration of covered SEMSs may offset their advantages in preventing tumor ingrowth. We conducted this multicenter, single-arm, retrospective study at six tertiary referral centers to evaluate the safety and efficacy of a partially covered SEMS with an uncovered large-bore flare at the proximal end as an antimigration system in 41 patients with symptomatic malignant GOO. The primary outcome was clinical success, and the secondary outcomes were technical success, stent dysfunction, adverse events, and survival after stent placement. The technical and clinical success rates were 100% and 95%, respectively. Stent dysfunctions occurred in 17 patients (41%), including stent migration in nine (23%), tumor ingrowth in one (2%), and tumor overgrowth in four (10%). Two patients (5%) developed adverse events: one pancreatitis and one perforation. No procedure-related death was observed. A novel partially covered SEMS with a large-bore flare proximal end was safe and effective for malignant GOO but failed to prevent stent migration. Further research is warranted to develop a covered SEMS with an optimal antimigration system.

Clinical remission following endoscopic placement of retrievable, fully covered metal stents in patients with esophageal achalasia.

Science.gov (United States)

Zeng, Y; Dai, Y-M; Wan, X-J

2014-01-01

Metal stents may represent an alternative therapy in the treatment of achalasia. We therefore evaluated the effectiveness of retrievable, fully covered metal stents in patients with achalasia. Fifty-nine patients with achalasia were treated with retrievable, fully covered metal stents. Symptoms using a global symptom score (0-10), lower esophageal sphincter (LES) resting pressure, LES relaxation, and simultaneous contraction of the esophagus were analyzed before and 1 week and 1 month after intervention. Complications and treatment outcomes were followed up at 6, 12, 18, and 24 months postoperatively. Stent placement was successful, and clinical symptoms resolved (P treatment in patients with achalasia. © 2013 Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

Large-Area, High-Resolution Tree Cover Mapping with Multi-Temporal SPOT5 Imagery, New South Wales, Australia

Directory of Open Access Journals (Sweden)

Adrian Fisher

2016-06-01

Full Text Available Tree cover maps are used for many purposes, such as vegetation mapping, habitat connectivity and fragmentation studies. Small remnant patches of native vegetation are recognised as ecologically important, yet they are underestimated in remote sensing products derived from Landsat. High spatial resolution sensors are capable of mapping small patches of trees, but their use in large-area mapping has been limited. In this study, multi-temporal Satellite pour l’Observation de la Terre 5 (SPOT5 High Resolution Geometrical data was pan-sharpened to 5 m resolution and used to map tree cover for the Australian state of New South Wales (NSW, an area of over 800,000 km2. Complete coverages of SPOT5 panchromatic and multispectral data over NSW were acquired during four consecutive summers (2008–2011 for a total of 1256 images. After pre-processing, the imagery was used to model foliage projective cover (FPC, a measure of tree canopy density commonly used in Australia. The multi-temporal imagery, FPC models and 26,579 training pixels were used in a binomial logistic regression model to estimate the probability of each pixel containing trees. The probability images were classified into a binary map of tree cover using local thresholds, and then visually edited to reduce errors. The final tree map was then attributed with the mean FPC value from the multi-temporal imagery. Validation of the binary map based on visually assessed high resolution reference imagery revealed an overall accuracy of 88% (±0.51% standard error, while comparison against airborne lidar derived data also resulted in an overall accuracy of 88%. A preliminary assessment of the FPC map by comparing against 76 field measurements showed a very good agreement (r2 = 0.90 with a root mean square error of 8.57%, although this may not be representative due to the opportunistic sampling design. The map represents a regionally consistent and locally relevant record of tree cover for NSW, and

Covering techniques for severe burn treatment: lessons for radiological burn accidents

International Nuclear Information System (INIS)

Carsin, H.; Stephanazzi, J.; Lambert, F.; Curet, P.M.; Gourmelon, P.

2002-01-01

Covering techniques for severe burn treatment: lessons for radiological burn accidents. After a severe burn, the injured person is weakened by a risk of infection and a general inflammation. The necrotic tissues have to be removed because they are toxic for the organism. The injured person also needs to be covered by a cutaneous envelope, which has to be done by a treatment centre for burned people. The different techniques are the following: - auto grafts on limited burned areas; - cutaneous substitutes to cover temporary extended burned areas. Among them: natural substitutes like xenografts (pork skin, sheep skin,..) or allografts (human skin), - treated natural substitutes which only maintain the extracellular matrix. Artificial skins belong to this category and allow the development of high quality scars, - cell cultures in the laboratory: multiplying the individual cells and grafting them onto the patient. This technique is not common but allows one to heal severely injured patients. X-ray burns are still a problem. Their characteristics are analysed: intensive, permanent, antalgic resistant pain. They are difficult to compare with heat burns. In spite of a small number of known cases, we can give some comments and guidance on radio necrosis cures: the importance of the patients comfort, of ending the pain, of preventing infection, and nutritional balance. At the level of epidermic inflammation and phlyctena (skin blisters), the treatment may be completed by the use of growth factors. At the level of necrosis, after a temporary cover, an auto graft can be considered only if a healthy basis is guaranteed. The use of cellular cultures in order to obtain harmonious growth factors can be argued. (author)

Diabetes-related emotional distress in Dutch and U.S. diabetic patients: cross-cultural validity of the problem areas in diabetes scale

NARCIS (Netherlands)

Snoek, F. J.; Pouwer, F.; Welch, G. W.; Polonsky, W. H.

2000-01-01

To examine the cross-cultural validity of the Problem Areas in Diabetes Scale (PAID) in Dutch and U.S. diabetic patients. A total of 1,472 Dutch people with diabetes completed the PAID along with other self-report measures of affect. Statistics covered Cronbach's alpha, exploratory factor analysis

Forward-looking Assimilation of MODIS-derived Snow Covered Area into a Land Surface Model

Science.gov (United States)

Zaitchik, Benjamin F.; Rodell, Matthew

2008-01-01

Snow cover over land has a significant impact on the surface radiation budget, turbulent energy fluxes to the atmosphere, and local hydrological fluxes. For this reason, inaccuracies in the representation of snow covered area (SCA) within a land surface model (LSM) can lead to substantial errors in both offline and coupled simulations. Data assimilation algorithms have the potential to address this problem. However, the assimilation of SCA observations is complicated by an information deficit in the observation SCA indicates only the presence or absence of snow, and not snow volume and by the fact that assimilated SCA observations can introduce inconsistencies with atmospheric forcing data, leading to non-physical artifacts in the local water balance. In this paper we present a novel assimilation algorithm that introduces MODIS SCA observations to the Noah LSM in global, uncoupled simulations. The algorithm utilizes observations from up to 72 hours ahead of the model simulation in order to correct against emerging errors in the simulation of snow cover while preserving the local hydrologic balance. This is accomplished by using future snow observations to adjust air temperature and, when necessary, precipitation within the LSM. In global, offline integrations, this new assimilation algorithm provided improved simulation of SCA and snow water equivalent relative to open loop integrations and integrations that used an earlier SCA assimilation algorithm. These improvements, in turn, influenced the simulation of surface water and energy fluxes both during the snow season and, in some regions, on into the following spring.

Scenarios of land cover in China

Science.gov (United States)

Yue, Tian Xiang; Fan, Ze Meng; Liu, Ji Yuan

2007-02-01

A method for surface modeling of land cover change (SMLC) is developed on the basis of establishing transition probability matrixes between land cover types and HLZ types. SMLC is used to simulate land cover scenarios of China for the years 2039, 2069 and 2099, for which HLZ scenarios are first simulated in terms of HadCM3 climatic scenarios that are downscaled in zonal model of spatial climate change in China. This paper also analyzes spatial distribution of land cover types, area change and mean center shift of each land cover type, ecotope diversity, and patch connectivity under the land cover scenarios. The results show that cultivated land would decrease and woodland would expand greatly with climatic change, which coincides with consequences expected by implementation of Grain-for-Green policy. Nival area would shrink, and desertification area would expand at a comparatively slow rate in future 100 years. Climate change would generally cause less ecotope diversity and more patch connectivity. Ecosystems in China would have a pattern of beneficial cycle after efficient ecological conservation and restoration. However, if human activities would exceed regulation capacity of ecosystems themselves, the ecosystems in China might deteriorate more seriously.

Dust pollution of snow cover in the industrial areas of Tomsk city (Western Siberia, Russia)

OpenAIRE

Talovskaya, Anna Valerievna; Filimonenko, Ekaterina Anatolievna; Osipova, Nina Aleksandrovna; Yazikov, Yegor (Egor) Grigoryevich; Nadeina, Louise Vasilievna

2016-01-01

This article describes the results of long-term monitoring (2007-2014) of snow cover pollution in the territory of Tomsk city. Snow samples were collected in the territory of Tomsk. Determination of dust load level was carried out by comparing with the background and reference values. It has been determined that the north-east and central parts of Tomsk are the most contaminated areas, where brickworks, coal and gas-fired thermal power plant are located. The analysis of long-term dynamics sho...

Cloud Cover Assessment for Operational Crop Monitoring Systems in Tropical Areas

Directory of Open Access Journals (Sweden)

Isaque Daniel Rocha Eberhardt

2016-03-01

Full Text Available The potential of optical remote sensing data to identify, map and monitor croplands is well recognized. However, clouds strongly limit the usefulness of optical imagery for these applications. This paper aims at assessing cloud cover conditions over four states in the tropical and sub-tropical Center-South region of Brazil to guide the development of an appropriate agricultural monitoring system based on Landsat-like imagery. Cloudiness was assessed during overlapping four months periods to match the typical length of crop cycles in the study area. The percentage of clear sky occurrence was computed from the 1 km resolution MODIS Cloud Mask product (MOD35 considering 14 years of data between July 2000 and June 2014. Results showed high seasonality of cloud occurrence within the crop year with strong variations across the study area. The maximum seasonality was observed for the two states in the northern part of the study area (i.e., the ones closer to the Equator line, which also presented the lowest averaged values (15% of clear sky occurrence during the main (summer cropping period (November to February. In these locations, optical data faces severe constraints for mapping summer crops. On the other hand, relatively favorable conditions were found in the southern part of the study region. In the South, clear sky values of around 45% were found and no significant clear sky seasonality was observed. Results underpin the challenges to implement an operational crop monitoring system based solely on optical remote sensing imagery in tropical and sub-tropical regions, in particular if short-cycle crops have to be monitored during the cloudy summer months. To cope with cloudiness issues, we recommend the use of new systems with higher repetition rates such as Sentinel-2. For local studies, Unmanned Aircraft Vehicles (UAVs might be used to augment the observing capability. Multi-sensor approaches combining optical and microwave data can be another

Strontium-90 and plutonium-239/240 accumulation and distribution in soil-vegetative cover of some Semipalatinsk test site areas

International Nuclear Information System (INIS)

Tuleubaev, B.A.; Artem'ev, O.I.; Luk'yanova, Yu.A.; Sidorovich, T.V.; Silkina, G.P.; Kurmanbaeva, D.S.

2001-01-01

This paper presents results of field and laboratory studies of soil-vegetative cover contamination by 90 Sr and 239/240 Pu. Certain parameters of radionuclide migration in the environment of some former Semipalatinsk Test Site areas were determined. (author)

A large-area, spatially continuous assessment of land cover map error and its impact on downstream analyses.

Science.gov (United States)

Estes, Lyndon; Chen, Peng; Debats, Stephanie; Evans, Tom; Ferreira, Stefanus; Kuemmerle, Tobias; Ragazzo, Gabrielle; Sheffield, Justin; Wolf, Adam; Wood, Eric; Caylor, Kelly

2018-01-01

Land cover maps increasingly underlie research into socioeconomic and environmental patterns and processes, including global change. It is known that map errors impact our understanding of these phenomena, but quantifying these impacts is difficult because many areas lack adequate reference data. We used a highly accurate, high-resolution map of South African cropland to assess (1) the magnitude of error in several current generation land cover maps, and (2) how these errors propagate in downstream studies. We first quantified pixel-wise errors in the cropland classes of four widely used land cover maps at resolutions ranging from 1 to 100 km, and then calculated errors in several representative "downstream" (map-based) analyses, including assessments of vegetative carbon stocks, evapotranspiration, crop production, and household food security. We also evaluated maps' spatial accuracy based on how precisely they could be used to locate specific landscape features. We found that cropland maps can have substantial biases and poor accuracy at all resolutions (e.g., at 1 km resolution, up to ∼45% underestimates of cropland (bias) and nearly 50% mean absolute error (MAE, describing accuracy); at 100 km, up to 15% underestimates and nearly 20% MAE). National-scale maps derived from higher-resolution imagery were most accurate, followed by multi-map fusion products. Constraining mapped values to match survey statistics may be effective at minimizing bias (provided the statistics are accurate). Errors in downstream analyses could be substantially amplified or muted, depending on the values ascribed to cropland-adjacent covers (e.g., with forest as adjacent cover, carbon map error was 200%-500% greater than in input cropland maps, but ∼40% less for sparse cover types). The average locational error was 6 km (600%). These findings provide deeper insight into the causes and potential consequences of land cover map error, and suggest several recommendations for land

Monitoring urban expansion and land use/land cover changes of Shanghai metropolitan area during the transitional economy (1979-2009) in China.

Science.gov (United States)

Yin, Jie; Yin, Zhane; Zhong, Haidong; Xu, Shiyuan; Hu, Xiaomeng; Wang, Jun; Wu, Jianping

2011-06-01

This study explored the spatio-temporal dynamics and evolution of land use/cover changes and urban expansion in Shanghai metropolitan area, China, during the transitional economy period (1979-2009) using multi-temporal satellite images and geographic information systems (GIS). A maximum likelihood supervised classification algorithm was employed to extract information from four landsat images, with the post-classification change detection technique and GIS-based spatial analysis methods used to detect land-use and land-cover (LULC) changes. The overall Kappa indices of land use/cover change maps ranged from 0.79 to 0.89. Results indicated that urbanization has accelerated at an unprecedented scale and rate during the study period, leading to a considerable reduction in the area of farmland and green land. Findings further revealed that water bodies and bare land increased, obviously due to large-scale coastal development after 2000. The direction of urban expansion was along a north-south axis from 1979 to 2000, but after 2000 this growth changed to spread from both the existing urban area and along transport routes in all directions. Urban expansion and subsequent LULC changes in Shanghai have largely been driven by policy reform, population growth, and economic development. Rapid urban expansion through clearing of vegetation has led to a wide range of eco-environmental degradation.

Land related grievances shape tropical forest-cover in areas affected by armed-conflict

DEFF Research Database (Denmark)

Nunez, Augusto Carlos Castro; Mertz, Ole; Buritica, Alexander

2017-01-01

Armed-conflicts often occur in tropical areas considered to be of high ‘conservation-value’, termed as such for their biodiversity or carbon-storage functions. Despite this important overlap, few studies have assessed how forest-biomass is affected by armed-conflicts. Thus, in this paper we develop...... a multinomial logit model to examine how outcomes of the interactions between carbon-storage, armed-conflict and deforestation rates are linked to social, institutional and economic factors. We use Colombia as a case study because of its protracted armed-conflict, high forest-cover, sustained deforestation......-ownership disputes, the Colombian government might uphold their international climate change commitments via reducing deforestation and hence forest based carbon emissions, while pursuing their national security objective via undermining opportunities for guerrilla groups to operate....

Silicone covered vs. Non- covered endotracheal self expandable metallic stent: An experimental study

Energy Technology Data Exchange (ETDEWEB)

Do, Young Soo; Lee, Byung Hee; Kim, Soo Ah; Kim, Kie Hwan; Chin, Soo Yil; Cho, Kyung Ja; Cho, Dae Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

1994-10-15

To evaluate pathologic changes of the trachea and the lung after insertion of silicone covered and non covered Gianturco stent in the trachea of dog. Silicone covered(covered) and non covered(bare) Gianturco stent, six in each, were inserted into the tracheal lumen of six consecutive dogs. After 1-10 weeks observation, the dogs were sacrificed and their tracheas and lungs were examined grossly and histopathologically. Serial chest radiographs were performed to evaluate pneumonia and stent migration every 3-5 days. Pneumonia was observed in one of bare stent group and five of covered stent group. Stent migration was noted in three of covered stent group. In bare stent group, the epithelium of the trachea was markedly thickened by hyperplasia and stent was covered by granulation tissue from 6 weeks after stent insertion. Inflammation was focal at contact site between the stent and the trachea. In covered stent group, the epithelium was denuded at multiple areas and there were multifocal squamous metaplasia of the mucosa. Inflammatory reaction of the trachea was diffuse. Inflammatory reaction was more severe and stent migration was more frequent in covered stent group. The use of covered stent in the trachea should be studied further.

Functional MRI in Patients with Intracranial Lesions near Language Areas.

Science.gov (United States)

Hakyemez, B; Erdogan, C; Yildirim, N; Bora, I; Bekar, A; Parlak, M

2006-06-30

We aimed to depict Broca's area and Wernicke's area by word generation and sentence formation paradigms in patients with various intracranial lesions adjacent to language areas using functional MRI technique and to evaluate the ability of functional MRI to lateralize the hemispheric dominance for language. Twenty-three right-handed patients were included in this study. Lesions were classified as low-grade glioma (n=8), high-grade glioma (n=9), metastasis (n=1), meningioma (n=1), arteriovenous malformation (n=2) and mesial temporal sclerosis (n=2). We performed blood-oxygenated-level-dependant functional MRI using a 1.5-T unit. Word generation and sentence formation tasks were used to activate language areas. Language areas were defined as Brodmann 44, 45 (Broca's area) and Brodmann 22 area (Wernicke's area). Laterality index was used to show the dominant hemisphere. Two poorly cooperative patients showed no activation and were excluded from the study. Broca's area was localized in 21 patients (100 %). Wernicke's area, on the other hand, could only be localized in eight of the 21 patients (38 %).The left hemisphere was dominant in 86% of patients while atypical language lateralization (right or bilateral) was demonstrated in 14% of the patients. Bilateral activation areas were shown in 10% of those patients while right cerebral hemisphere was dominant in 4% of the patients. Word generation and sentence formation tasks are especially helpful in localizing Broca's area. Wernicke's area could also be demonstrated in some of the cases. Functional MRI can be used as an important and useful means of demonstrating language areas in patients with lesions adjacent to those areas and depicting the hemispheric dominance.

Covered stent placement for the treatment of malignant superior vena cava syndrome: Is unilateral covered stenting and effective?

International Nuclear Information System (INIS)

Cho, Young Hoon; Gwon, Dong Il; Ko, Gi Young; Ko, Heung Kyu; Kim, Jin Hyoung; Shin, Ji Hoon; Yoon, Hyun Ki; Sung, Kyu Bo

2014-01-01

To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome. Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins. Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively. Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.

Covered stent placement for the treatment of malignant superior vena cava syndrome: Is unilateral covered stenting and effective?

Energy Technology Data Exchange (ETDEWEB)

Cho, Young Hoon; Gwon, Dong Il; Ko, Gi Young; Ko, Heung Kyu; Kim, Jin Hyoung; Shin, Ji Hoon; Yoon, Hyun Ki; Sung, Kyu Bo [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

2014-02-15

To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome. Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins. Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively. Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.

A Water Balance Study of Four Landfill Cover Designs at Material Disposal Area B in Los Alamos, New Mexico

Energy Technology Data Exchange (ETDEWEB)

David D. Breshears; Fairley J. Barnes; John W. Nyhan; Johnny A. Salazar

1998-09-01

The goal of disposing of low-level radioactive and hazardous waste in shallow landfills is to reduce risk to human health and the environment by isolating contaminants until they no longer pose an unacceptable hazard. In order to achieve this, the Department of Energy Environmental Restoration Program is comparing the performance of several different surface covers at Material Disposal Area (MDA) B in Los Alamos. Two conventional landfill were compared with an improved cover designed to minimize plant and animal intrusion and to minimize water infiltration into the underlying wastes. The conventional covers varied in depth and both conventional and improved designs had different combinations of vegetation (grass verses shrub) and gravel mulch (no mulch verses mulch). These treatments were applied to each of 12 plots and water balance parameters were measured from March1987 through June 1995. Adding a gravel mulch significantly influenced the plant covered field plots receiving no gravel mulch averaged 21.2% shrub cover, while plots with gravel had a 20% larger percent cover of shrubs. However, the influence of gravel mulch on the grass cover was even larger than the influence on shrub cover, average grass cover on the plots with no gravel was 16.3%, compared with a 42% increase in grass cover due to gravel mulch. These cover relationships are important to reduce runoff on the landfill cover, as shown by a regression model that predicts that as ground cover is increased from 30 to 90%,annual runoff is reduced from 8.8 to 0.98 cm-a nine-fold increase. We also found that decreasing the slope of the landfill cover from 6 to 2% reduced runoff from the landfill cover by 2.7-fold. To minimize the risk of hazardous waste from landfills to humans, runoff and seepage need to be minimized and evapotranspiration maximized on the landfill cover. This has to be accomplished for dry and wet years at MDA B. Seepage consisted of 1.9% and 6.2% of the precipitation in the average and

Modeling of surface dust concentration in snow cover at industrial area using neural networks and kriging

Science.gov (United States)

Sergeev, A. P.; Tarasov, D. A.; Buevich, A. G.; Shichkin, A. V.; Tyagunov, A. G.; Medvedev, A. N.

2017-06-01

Modeling of spatial distribution of pollutants in the urbanized territories is difficult, especially if there are multiple emission sources. When monitoring such territories, it is often impossible to arrange the necessary detailed sampling. Because of this, the usual methods of analysis and forecasting based on geostatistics are often less effective. Approaches based on artificial neural networks (ANNs) demonstrate the best results under these circumstances. This study compares two models based on ANNs, which are multilayer perceptron (MLP) and generalized regression neural networks (GRNNs) with the base geostatistical method - kriging. Models of the spatial dust distribution in the snow cover around the existing copper quarry and in the area of emissions of a nickel factory were created. To assess the effectiveness of the models three indices were used: the mean absolute error (MAE), the root-mean-square error (RMSE), and the relative root-mean-square error (RRMSE). Taking into account all indices the model of GRNN proved to be the most accurate which included coordinates of the sampling points and the distance to the likely emission source as input parameters for the modeling. Maps of spatial dust distribution in the snow cover were created in the study area. It has been shown that the models based on ANNs were more accurate than the kriging, particularly in the context of a limited data set.

Preliminary clinical application in the cranial internal carotid artery of covered stents specially designed for intracranial vasculature

International Nuclear Information System (INIS)

Li Minghua; Luo Qiyi; Fang Chun; Xie Zhiyong; Cheng Yingsheng; Gao Bulang; Li Yu; Zhang Beilei; Xie Jian; Wang Yongli

2007-01-01

Objective: To investigate the flexibility of both the covered stents specially designed for use in intracranial vasculature and the delivering system in passing through the bone tube and the physiological curves of the cranial internal carotid artery (CICA) to reach the targeted area, the performance (adherence) of the covered stents in occluding vascular wall diseases and the impact on the vascular branches of the covered segment. Methods: The covered stents specially designed for use in intracranial vasculature were used to treat 13 patients with CICA diseases using endovascular techniques. There were 4 huge pseudoaneurysms, 4 giant aneurysms, 3 small wide-necked aneurysms, 1 giant pseudoaneurysm with concurrent internal carotid cavernous fistula (CCF), and 1 CCF. Prior to the detachment of the covered stents, balloon occlusion test (BOT) of the internal carotid artery on the diseased side and whole-brain digital subtraction angiography (DSA) were performed in all the patients. Three to 16 months following procedure, DSA and clinical follow-ups were performed. Results: Thirteen patients all tolerated the BOT well with the DSA demonstrating well-opened anterior and posterior communicating arteries. The covered stents and the delivering systems all successfully passed CICA to reach the targeted diseased area, with the diseased segments of the internal carotid artery including C3-C4 in 4 cases, C4-C5 in 4 and C6-C7 in 5. Immediately following the detachment of the covered stents, DSA demonstrated that 7 aneurysms were completely occluded, 4 aneurysms had slight endoleak, and 1 CCF had markedly-decreased blood flow through the fistula. In the patient with concurrent pseudoaneurysm and CCF, the pseudoaneurysm disappeared and the blood flow through the fistula was markedly-reduced immediately following the stenting procedure. Apart from one patient with aneurysmal subarachnoid hemorrhage who died due to extensive vascular spasm on the 9th day following the stenting

Urban land use and land cover change analysis and modeling a case study area Malatya, Turkey

OpenAIRE

Baysal, Gülendam

2013-01-01

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies. This research was conducted to analyze the land use and land cover changes and to model the changes for the case study area Malatya, Turkey. The first step of the study was acquisition of multi temporal data in order to detect the changes over the time. For this purpose satellite images (Landsat 1990-2000-2010) have been used. In order to acquire data from satel...

Land cover fire proneness in Europe

Directory of Open Access Journals (Sweden)

Mario Gonzalez Pereira

2014-12-01

Full Text Available Aim of study: This study aims to identify and characterize the spatial and temporal evolution of the types of vegetation that are most affected by forest fires in Europe. The characterization of the fuels is an important issue of the fire regime in each specific ecosystem while, on the other hand, fire is an important disturbance for global vegetation dynamics.Area of study: Southern European countries: Portugal, Spain, France, Italy and Greece.Material and Methods: Corine Land Cover maps for 2000 and 2006 (CLC2000, CLC2006 and burned area (BA perimeters, from 2000 to 2013 in Europe are combined to access the spatial and temporal evolution of the types of vegetation that are most affected by wild fires using descriptive statistics and Geographical Information System (GIS techniques.Main results: The spatial and temporal distribution of BA perimeters, vegetation and burnt vegetation by wild fires was performed and different statistics were obtained for Mediterranean and entire Europe, confirming the usefulness of the proposed land cover system. A fire proneness index is proposed to assess the fire selectivity of land cover classes. The index allowed to quantify and to compare the propensity of vegetation classes and countries to fire.Research highlights: The usefulness and efficiency of the land cover classification scheme and fire proneness index. The differences between northern Europe and southern Europe and among the Mediterranean region in what concerns to vegetation cover, fire incidence, area burnt in land cover classes and fire proneness between classes for the different countries.Keywords: Fire proneness; Mixed forests; Land cover/land use; Fire regime; Europe; GIS; Corine land cover. 

Spatial and temporal analysis of the land cover in riparian buffer zones (Areas for Permanent Preservation in Sorocaba City, SP, Brazil

Directory of Open Access Journals (Sweden)

Sergio Henrique Alves

2009-08-01

Full Text Available Considering the fundamental role that the riparian vegetation plays in relation to maintenance of the environmental health of a watershed and the necessity of restoring sectors of the buffer zone without natural vegetation, in this paper we investigated what land cover classes occur along the riparian buffer stripes considered Area for Permanent Preservation (APP in the Sorocaba municipality, SP in three periods: 1988, 1995 and 2003. Based on GIS technology and using the drainage network map, the APP stripes (riparian buffer zones map was generated, and this map was overlaid to the land cover map (1988, 1995 and 2003 to provide a land cover map specifically of the riparian buffer zones. The results show that 58.43% of the APPs have no land cover of native vegetation and therefore, need to be reforested, representing 5,400 hectares to be restored.

Forest value and optimal rotations in continuous cover forestry

DEFF Research Database (Denmark)

Jacobsen, Jette Bredahl; Jensen, Frank; Thorsen, Bo Jellesmark

2018-01-01

The Faustmann forest rotation model is a celebrated contribution in economics. The model provides a forest value expression and allows a solution to the optimal rotation problem valid for perpetual rotations of even-aged forest stands. However, continuous forest cover forest management systems......, but rigorous mathematical model of the continuous cover forest, which strictly focuses on the area use dynamics that such an uneven-aged forest must have in equilibrium. This implies explicitly accounting for area reallocation and for weighting the productivity of each age class by the area occupied. We...... present results for unrestricted as well as area-restricted versions of the models. We find that land values are unambiguously higher in the continuous cover forest models compared with the even-aged models. Under area restrictions, the optimal rotation age in a continuous cover forest model...

The Analysis of Land Use Based on CORINE Land Cover in the Romanian Part of the Tisa Catchment Area

Directory of Open Access Journals (Sweden)

CIPRIAN MOLDOVAN

2010-01-01

Full Text Available The analysis of the land use structure of the 13 counties of the Romanian part of Tisa catchment area has been made according to the 2000 edition of CORINE Land Cover, while the 1990 edition has been used for comparative purposes. Out of the total area of 8,269,229.48 hectares, the forests cover 37.92%, the arable lands 35.02% and the grasslands 17.97%. The other types of land use have lower weights, such as the continuous and discontinuous urban fabric 4.81%, the orchards 1.10% and the vineyards 0.98%. In the category of forests, the following types of land use are included: broad-leaved forests, which form the majority (24.72%, coniferous forests (6.22%, mixed forests (3.46% and transitional woodland-shrub areas (3.52%. The forests are mainly located in the Carpathians and the hills. The non-irrigated arable lands (23.50% are predominant within the arable lands. They lie mostly in the Western Plain and in the basins and corridors of the Transylvanian Depression and the Western Hills. The analysis of the dynamics of the land use structure between 1990 and 2000 indicates a relative stability in the case of forests, a decrease of arable lands and an increase of grasslands.

Evaluation of postoperative patient satisfaction after covering the nasal dorsum with upper lateral cartilage: "upper lateral closing".

Science.gov (United States)

Çağıcı, Can Alper

2017-11-16

Following nasal hump removal during septorhinoplasty, the middle vault should be reconstructed to avoid functional and esthetic problems. Middle vault reconstruction, however, may result in widening of the middle vault and may need a camouflage graft to cover dorsal irregularities. To present the results of reconstructing the middle vault with a technique that covers the nasal dorsum with upper lateral cartilage, from the viewpoint of patient satisfaction. Retrospective study of patients who underwent septorhinoplasty that included nasal dorsum closure with upper lateral cartilage from December 1, 2014 to January 31, 2016. Those with postoperative follow-up of less than 3 months were excluded. The final study group included 39 patients. The same surgeon performed all septorhinoplasties. The dorsum was closed using an "upper lateral closing" technique that approximated upper lateral cartilages to each other over the septum. Postoperative patient satisfaction was determined using a visual analog scale and the rhinoplasty outcomes evaluation questionnaire. The questionnaire evaluates patient esthetic and functional satisfaction with the operated nose. High scores indicate improved esthetic results. No dorsal irregularities were seen at postoperative follow-up evaluation of the patients. For esthetic nasal appearance, the median visual analogue scale scores was 86%, and the mean for the questionnaire was 77.03%. The natural dome-shaped anatomy of the nasal dorsum was achieved by approximating the upper lateral cartilages to each other. Closing the dorsum with this technique also covers any dorsal irregularities and results in a smooth dorsum. Patients expressed satisfaction with the esthetic and functional aspects of the smooth, attractive nasal dorsum. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Emerging factors associated with the decline of a gray fox population and multi-scale land cover associations of mesopredators in the Chicago metropolitan area.

Energy Technology Data Exchange (ETDEWEB)

Willingham, Alison N.; /Ohio State U.

2008-01-01

Statewide surveys of furbearers in Illinois indicate gray (Urocyon cinereoargenteus) and red (Vulpes vulpes) foxes have experienced substantial declines in relative abundance, whereas other species such as raccoons (Procyon lotor) and coyotes (Canis latrans) have exhibited dramatic increases during the same time period. The cause of the declines of gray and red foxes has not been identified, and the current status of gray foxes remains uncertain. Therefore, I conducted a large-scale predator survey and tracked radiocollared gray foxes from 2004 to 2007 in order to determine the distribution, survival, cause-specific mortality sources and land cover associations of gray foxes in an urbanized region of northeastern Illinois, and examined the relationships between the occurrence of gray fox and the presence other species of mesopredators, specifically coyotes and raccoons. Although generalist mesopredators are common and can reach high densities in many urban areas their urban ecology is poorly understood due to their secretive nature and wariness of humans. Understanding how mesopredators utilize urbanized landscapes can be useful in the management and control of disease outbreaks, mitigation of nuisance wildlife issues, and gaining insight into how mesopredators shape wildlife communities in highly fragmented areas. I examined habitat associations of raccoons, opossums (Didelphis virginiana), domestic cats (Felis catus), coyotes, foxes (gray and red), and striped skunks (Mephitis mephitis) at multiple spatial scales in an urban environment. Gray fox occurrence was rare and widely dispersed, and survival estimates were similar to other studies. Gray fox occurrence was negatively associated with natural and semi-natural land cover types. Fox home range size increased with increasing urban development suggesting that foxes may be negatively influenced by urbanization. Gray fox occurrence was not associated with coyote or raccoon presence. However, spatial avoidance and

Total pleural covering technique for intractable pneumothorax in patient with Ehlers-Danlos syndrome.

Science.gov (United States)

Kadota, Yoshihisa; Fukui, Eriko; Kitahara, Naoto; Okura, Eiji; Ohta, Mitsunori

2016-07-01

We report a patient with vascular-type Ehlers-Danlos syndrome (vEDS) who developed pneumothorax and was treated with a total pleural covering technique (TPC). A 24-year-old man developed repeat pneumothorax with intermittent hemo-sputum. Based on unusual radiological manifestations of lung lesions and physical findings, EDS was suspected as an underlying cause of the pneumothorax. Surgical treatment was performed using a mediastinal fat pad and TPC, and no relapse was seen up to 2 years after surgery. TPC is a less invasive surgical approach for selected patients with vEDS. Accurate underlying diagnosis of vEDS and systemic evaluation of vascular complications are necessary before planning surgery.

Surface lowering of the debris-covered area of Kanchenjunga Glacier in the eastern Nepal Himalaya since 1975, as revealed by Hexagon KH-9 and ALOS satellite observations

Science.gov (United States)

Lamsal, Damodar; Fujita, Koji; Sakai, Akiko

2017-12-01

This study presents the geodetic mass balance of Kanchenjunga Glacier, one of the largest debris-covered glaciers in the easternmost Nepal Himalaya, which possesses a negative mass balance of -0.18 ± 0.17 m w.e. a-1 for the 1975-2010 study period, estimated using digital elevation models (DEMs) generated from Hexagon KH-9 and ALOS PRISM stereo images. Accurate DEMs, with a relative uncertainty of ±5.5 m, were generated from the intensive and manual editing of triangulated irregular network (TIN) models on a stereo MirrorTM/3D Monitor. The glacier ice-flow velocity field was also calculated using a feature-tracking method that was applied to two ALOS orthoimages taken in 2010. The elevation differences between the two DEMs highlight considerable surface lowering across the debris-covered area, and a slight thickening in the accumulation area of Kanchenjunga Glacier between 1975 and 2010. The magnitude and gradient of surface lowering are similar among the six glacier tributaries, even though they are situated at different elevations, which may reflect variations in the ice-flow velocity field. The pattern of surface lowering correlates well with the ice-flow velocity field over the debris-covered portion of the main tributary, suggesting that the glacier dynamics significantly affect surface lowering by altering the emergence velocity along the glacier, particularly in the compressive ablation area. Surface-lowering patterns partially correspond to the supraglacial pond area fraction of the glacier, with enhanced surface lowering observed in areas that possess a larger pond area fraction. These findings support the hypothesis that supraglacial ponds may intensify ice wastage and play a key role in the heterogeneous surface lowering of debris-covered glaciers. The estimated mass loss of Kanchenjunga Glacier is moderate compared with other debris-covered glaciers in neighboring Himalayan regions, which may be due to the lower pond area fraction of Kanchenjunga

Land cover changes in central Sonora Mexico

Science.gov (United States)

Diego Valdez-Zamudio; Alejandro Castellanos-Villegas; Stuart Marsh

2000-01-01

Remote sensing techniques have been demonstrated to be very effective tools to help detect, analyze, and evaluate land cover changes in natural areas of the world. Changes in land cover can generally be attributed to either natural or anthropogenic forces. Multitemporal satellite imagery and airborne videography were used to detect, analyze, and evaluate land cover...

Effects of tourism and globalization on land cover and the influence on the quality of life of Paphos area in Cyprus

Science.gov (United States)

Italos, Chrysostomos; Akylas, Evangelos; Hadjimitsis, Diofantos G.

2014-08-01

Since 1960 most of the coastal area cites across the Mediterranean Sea concentrates people due mass immigration of people from the rural to urban areas. The extensive tourism development especially across the coastal areas, create demand of infrastructures and new work positions and intensive pressure to the environment. The new spirit of the globalization creates movability of people and goods around the word. The free transfer of people from countries with big population and low economical wealth, which are moved to areas where they can work. All the above generate demands of labor and Paphos is one of these areas where during the last decades was transformed from a small agriculture village in one excellent tourist destination. Across the coastal areas big tourist infrastructure was built and lot of different people travel from all areas around the word especially during the summer months. All these generate continuous changes to the environment, to the people and the society. The globalization of the universe commerce and the free transfer of goods and people modify the community stratification. The inflow of agricultures products from third countries reduces the local production and generates degradation and desertification of the rural areas. The periodical variation of the population of the area during the summer and winter periods affect to the environment. The increment demand of sources (water, energy and food) during the summer months pressurize the coastal strip area. By estimating a ratio of inflows by the outflows of goods, people and services of the study area and a ratio of the tourists by the local population, a general index can by arise which will clarify the effects on the environment on the study area. This paper presents the results obtained by this study by examining the effects of tourism on land cover and effects on quality of life for the Paphos area in Cyprus. The authors explores the potential of blending in the sustainability study the

Multispectral LiDAR Data for Land Cover Classification of Urban Areas

Directory of Open Access Journals (Sweden)

Salem Morsy

2017-04-01

Full Text Available Airborne Light Detection And Ranging (LiDAR systems usually operate at a monochromatic wavelength measuring the range and the strength of the reflected energy (intensity from objects. Recently, multispectral LiDAR sensors, which acquire data at different wavelengths, have emerged. This allows for recording of a diversity of spectral reflectance from objects. In this context, we aim to investigate the use of multispectral LiDAR data in land cover classification using two different techniques. The first is image-based classification, where intensity and height images are created from LiDAR points and then a maximum likelihood classifier is applied. The second is point-based classification, where ground filtering and Normalized Difference Vegetation Indices (NDVIs computation are conducted. A dataset of an urban area located in Oshawa, Ontario, Canada, is classified into four classes: buildings, trees, roads and grass. An overall accuracy of up to 89.9% and 92.7% is achieved from image classification and 3D point classification, respectively. A radiometric correction model is also applied to the intensity data in order to remove the attenuation due to the system distortion and terrain height variation. The classification process is then repeated, and the results demonstrate that there are no significant improvements achieved in the overall accuracy.

Multispectral LiDAR Data for Land Cover Classification of Urban Areas.

Science.gov (United States)

Morsy, Salem; Shaker, Ahmed; El-Rabbany, Ahmed

2017-04-26

Airborne Light Detection And Ranging (LiDAR) systems usually operate at a monochromatic wavelength measuring the range and the strength of the reflected energy (intensity) from objects. Recently, multispectral LiDAR sensors, which acquire data at different wavelengths, have emerged. This allows for recording of a diversity of spectral reflectance from objects. In this context, we aim to investigate the use of multispectral LiDAR data in land cover classification using two different techniques. The first is image-based classification, where intensity and height images are created from LiDAR points and then a maximum likelihood classifier is applied. The second is point-based classification, where ground filtering and Normalized Difference Vegetation Indices (NDVIs) computation are conducted. A dataset of an urban area located in Oshawa, Ontario, Canada, is classified into four classes: buildings, trees, roads and grass. An overall accuracy of up to 89.9% and 92.7% is achieved from image classification and 3D point classification, respectively. A radiometric correction model is also applied to the intensity data in order to remove the attenuation due to the system distortion and terrain height variation. The classification process is then repeated, and the results demonstrate that there are no significant improvements achieved in the overall accuracy.

Modeling percent tree canopy cover: a pilot study

Science.gov (United States)

John W. Coulston; Gretchen G. Moisen; Barry T. Wilson; Mark V. Finco; Warren B. Cohen; C. Kenneth Brewer

2012-01-01

Tree canopy cover is a fundamental component of the landscape, and the amount of cover influences fire behavior, air pollution mitigation, and carbon storage. As such, efforts to empirically model percent tree canopy cover across the United States are a critical area of research. The 2001 national-scale canopy cover modeling and mapping effort was completed in 2006,...

Object-based land cover classification and change analysis in the Baltimore metropolitan area using multitemporal high resolution remote sensing data

Science.gov (United States)

Weiqi Zhou; Austin Troy; Morgan Grove

2008-01-01

Accurate and timely information about land cover pattern and change in urban areas is crucial for urban land management decision-making, ecosystem monitoring and urban planning. This paper presents the methods and results of an object-based classification and post-classification change detection of multitemporal high-spatial resolution Emerge aerial imagery in the...

Esophagorespiratory fistula: treatment with self-expanding covered stent

International Nuclear Information System (INIS)

Zang Jian; Dou Yongchong; Wang Zheng; Kong Jian

2002-01-01

Objective: To evaluate self-expanding covered stent in the management of esophagorespiratory fistula. Methods: A self-expanding esophageal covered stent was implanted under fluoroscopic guidance in 13 patients with esophagorespiratory fistula. In this series patients aged 31-73 years (60.2 years in average). All patients had a pre-procedure fast of 6-41 days (17.3 days in average), in which 12 patients had pulmonary infection. Results: All fistulas were excluded and swallowing function was restored. No stend-related complication was observed. Pulmonary infection was managed in 10 patients out of 13. The mean survived time was 33.3 wks (1-178 wks) in follow-up. Conclusion: Covered self-expanding stent implantation is a safe and effective treatment of ERF

Forest cover disturbances in the South Taiga of West Siberia

Energy Technology Data Exchange (ETDEWEB)

Dyukarev, E A; Pologova, N N; Golovatskaya, E A; Dyukarev, A G, E-mail: egor@imces.ru [Institute of Monitoring of Climatic and Ecological Systems SB RAS, Akademicheskii Prospekt 10/3 (Russian Federation)

2011-07-15

Analysis of vegetation cover and tendencies in forest cover changes at a typical site in the south of West Siberia was performed using remote sensing observations from Landsat. The Northern Eurasia Land Cover legend was used for the assessment of unsupervised classification results. The land cover maps constructed have shown that about half of the study area is occupied by wetlands with several distinctively different vegetation types. The area studied is typical for the South Taiga zone (ecoregion) of Western Siberia from the Ob' river to the Irtysh river, where loamy and clayey soil forming rocks are widespread. Similar vegetation structures dominate over 600 000 km{sup 2}, or about 20%, of the West Siberia area. Analyses of the forest cover changes show that the forest cover loss is not very significant. The area of forest disturbed in 1990-9 is equal to 16 008 ha. The area of forest disturbances during the 2000-7 period was about twice as high (30 907 ha). The main reasons for the forest reduction are intensive forest harvesting and strong windthrow. The high sustainability of the region studied against anthropogenic impacts is explained by the high overall wetness of the territory, the small population density, and the prevalence of deciduous forests at different succession stages with rich vegetation cover.

EnviroAtlas - Land Cover for the Conterminous United States

Data.gov (United States)

U.S. Environmental Protection Agency — This dataset represents the percentage of land area that is classified as forest land cover, modified forest land cover, and natural land cover using the 2006...

Assessment of Land Use-Cover Changes and Successional Stages of Vegetation in the Natural Protected Area Altas Cumbres, Northeastern Mexico, Using Landsat Satellite Imagery

Directory of Open Access Journals (Sweden)

Uriel Jeshua Sánchez-Reyes

2017-07-01

Full Text Available Loss of vegetation cover is a major factor that endangers biodiversity. Therefore, the use of geographic information systems and the analysis of satellite images are important for monitoring these changes in Natural Protected Areas (NPAs. In northeastern Mexico, the Natural Protected Area Altas Cumbres (NPAAC represents a relevant floristic and faunistic patch on which the impact of loss of vegetation cover has not been assessed. This work aimed to analyze changes of land use and coverage (LULCC over the last 42 years on the interior and around the exterior of the area, and also to propose the time of succession for the most important types of vegetation. For the analysis, LANDSAT satellite images from 1973, 1986, 2000, 2005 and 2015 were used, they were classified in seven categories through a segmentation and maximum likelihood analysis. A cross-tabulation analysis was performed to determine the succession gradient. Towards the interior of the area, a significant reduction of tropical vegetation and, to a lesser extent, temperate forests was found, as well as an increase in scrub cover from 1973 to 2015. In addition, urban and vegetation-free areas, as well as modified vegetation, increased to the exterior. Towards the interior of the NPA, the processes of perturbation and recovery were mostly not linear, while in the exterior adjacent area, the presence of secondary vegetation with distinct definite time of succession was evident. The analysis carried out is the first contribution that evaluates LULCC in this important NPA of northeastern Mexico. Results suggest the need to evaluate the effects of these modifications on species.

Pharmacodynamic Comparison of Rocuronium Bromide between Patients from the Plateau Area and from the Plain Area.

Science.gov (United States)

Xie, Min; Huang, Jianxin; Li, Peng; Ou, Zhiyan; Hou, Jing

2016-06-23

We aimed to conduct a pharmacodynamic comparison of rocuronium bromide between patients from the plateau area and from the plain area. A total of 104 patients who received laparoscopic cholecystectomy in Sichuan Provincial People's Hospital and Aba Autonomous Prefecture People's Hospital from October 2015 to December 2015 were included in this study. Among them, 46 patients were from the plateau area and 58 were from the plain area. Both groups received total intravenous anesthesia (TIVA) with a dose of 0.6mg/kg rocuronium bromide during induction. In the meantime, neuromuscular block was monitored using a train-of-four (TOF) stimulation mode. The onset time (time to achieve the lowest TOF value after the injection of rocuronium bromide), duration of maximal neuromuscular block (duration of lowest T1 value), time to 25% recovery, time to 75% recovery, recovery index (time from 25% recovery to 75% recovery), time to extubation, length of stay in Post Anesthesia Care Unit (PACU) and muscle strength upon PACU discharge were all recorded. The onset time, time to 25% recovery, time to 75% recovery and time to extubation were all significantly prolonged in patients from the plateau area after receiving one single dose of rocuronium bromide (P0.05). Compared to patients from the plain area, patients from the plateau area showed prolonged onset time of rocuronium bromide, reduced metabolic capabilities and longer duration of muscular relaxation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Land cover changes in catchment areas of lakes situated in headwaters of the Tyśmienica River

Directory of Open Access Journals (Sweden)

Grzywna Antoni

2017-06-01

Full Text Available The paper presents the history of land cover changes in the catchment area of lakes situated in the headwaters of the Tyśmienica River. The basis of the study were topographic maps in scale 1:50 000, from 1936 and 2014. We analyzed the quantitative aspect of these changes. The study was conducted in three natural lakes (Rogóźno, Krasne, Łukcze, and in one lake transformed into a storage reservoir (Krzczeń. The technical issues of georeferencing maps in the Geographic Information System (GIS software are addressed first. In the landscape of Łęczna and Włodawa Lake District, to the end of the 19th century wetlands and bushes dominated. The first type of human pressure on this area was agriculture. Another type of pressure was recreation. In the catchment areas of studied lakes increased mainly the area of buildings and forests. Significantly increased also the length of roads and watercourses. Almost completely disappeared bushes and wastelands. In most of the analyzed basins, the area of wetlands and arable lands decreased. The probable cause of the changes in catchment use was decline in the water table, and thus overgrowing of meadows and wetlands.

The Thermal Collector With Varied Glass Covers

International Nuclear Information System (INIS)

Luminosu, I.; Pop, N.

2010-01-01

The thermal collector with varied glass covers represents an innovation realized in order to build a collector able to reach the desired temperature by collecting the solar radiation from the smallest surface, with the highest efficiency. In the case of the thermal collector with variable cover glasses, the number of the glass plates covering the absorber increases together with the length of the circulation pipe for the working fluid. The thermal collector with varied glass covers compared to the conventional collector better meet user requirements because: for the same temperature increase, has the collecting area smaller; for the same collection area, realizes the highest temperature increase and has the highest efficiency. This works is addressed to researchers in the solar energy and to engineers responsible with air-conditioning systems design or industrial and agricultural products drying.

On the impact of snow cover on daytime pollution dispersion

Science.gov (United States)

Segal, M.; Garratt, J. R.; Pielke, R. A.; Hildebrand, P.; Rogers, F. A.; Cramer, J.; Schanot, A.

A preliminary evaluation of the impact of snow cover on daytime pollutant dispersion conditions is made by using conceptual, scaling, and observational analyses. For uniform snow cover and synoptically unperturbed sunny conditions, observations indicate a considerate suppression of the surface sensible heat flux, the turbulence, and the development of the daytime atmospheric boundary layer (ABL) when compared to snow-free conditions. However, under conditions of non-uniform snow cover, as in urban areas, or associated with vegetated areas or bare ground patches, a milder effect on pollutant dispersion conditions would be expected. Observed concentrations of atmospheric particles within the ABL, and surface pollutant concentrations in urban areas, reflect the impact of snow cover on the modification of ABL characteristics.

Soil cover of gas-bearing areas

Science.gov (United States)

Mozharova, N. V.

2010-08-01

Natural soils with disturbed functioning parameters compared to the background soils with conservative technogenic-pedogenic features were distinguished on vast areas above the artificial underground gas storages in the zones of spreading and predominant impact of hydrocarbon gases. The disturbance of the functioning parameters is related to the increase in the methane concentration, the bacterial oxidation intensity and destruction, and the complex microbiological and physicochemical synthesis of iron oxides. The technogenic-pedogenic features include neoformations of bacteriomorphic microdispersed iron oxides. The impurity components consist of elements typical for biogenic structures. New soil layers, horizons, specific anthropogenically modified soils, and soil-like structures were formed on small areas in the industrial zones of underground gas storages due to the mechanical disturbance, the deposition of drilling sludge, and the chemical contamination. Among the soils, postlithogenic formations were identified—chemotechnosols (soddy-podzolic soils and chernozems), as well as synlithogenic ones: strato-chemotechnosols and stratochemoembryozems. The soil-like bodies included postlithogenic soil-like structures (chemotechnozems) and synlithogenic ones (strato-chemotechnozems). A substantive approach was used for the soil diagnostics. The morphological and magnetic profiles and the physical, chemical, and physicochemical properties of the soils were analyzed. The micromorphological composition of the soil magnetic fraction was used as a magnetic label.

Estimating the Fractional Vegetation Cover from GLASS Leaf Area Index Product

Directory of Open Access Journals (Sweden)

Zhiqiang Xiao

2016-04-01

Full Text Available The fractional vegetation cover (FCover is an essential biophysical variable and plays a critical role in the carbon cycle studies. Existing FCover products from satellite observations are spatially incomplete and temporally discontinuous, and also inaccurate for some vegetation types to meet the requirements of various applications. In this study, an operational method is proposed to calculate high-quality, accurate FCover from the Global LAnd Surface Satellite (GLASS leaf area index (LAI product to ensure physical consistency between LAI and FCover retrievals. As a result, a global FCover product (denoted by TRAGL were generated from the GLASS LAI product from 2000 to present. With no missing values, the TRAGL FCover product is spatially complete. A comparison of the TRAGL FCover product with the Geoland2/BioPar version 1 (GEOV1 FCover product indicates that these FCover products exhibit similar spatial distribution pattern. However, there were relatively large discrepancies between these FCover products over equatorial rainforests, broadleaf crops in East-central United States, and needleleaf forests in Europe and Siberia. Temporal consistency analysis indicates that TRAGL FCover product has continuous trajectories. Direct validation with ground-based FCover estimates demonstrated that TRAGL FCover values were more accurate (RMSE = 0.0865, and R2 = 0.8848 than GEOV1 (RMSE = 0.1541, and R2 = 0.7621.

Investigation the Vertical Distribution of Leaf Area and Dry Matter of Sweet Basil (Ocimum basilicum L., Borage (Borago officinalis L. and Cover Crops in Competition with Weeds

Directory of Open Access Journals (Sweden)

zeinab shirzadi margavi

2017-10-01

Full Text Available Introduction Distribution of leaf area and dry matter are the effective factors that influence on absorption the radiation, evaporation and transpiration of canopy and eventually dry matter accumulation and grain yield in plants. Plant canopy is the spatial arrangement of shoots in a plant population. In plant canopy, leaves are responsible for radiation absorption and gas exchange with the outside. Stem and branches arrange photosynthetic organs somehow, which gas exchange and light distribution best done. The effect of canopy structure on gas exchange and absorption of radiation in plant communities caused detailed study of the canopy structure to be more important. Materials and methods In order to investigate the vertical distribution of leaf area and dry matter of borage and sweet basil in competition with weeds by cover crops treatments, a field experiment was carried out in a randomized complete block design with 8 treatments and 3 replications in Agricultural Sciences and Natural Resources University of Sari in 2013. Treatments were cover crops mung bean (Vigna radiata L. and Persian clover (Trifolium resupinatum L. in the rows between the sweet basil (Ocimum basilicum L. and borage (Borago officinalis L.. Moreover, in order to evaluate the effectiveness of cover crops to control weeds, pure stand of sweet basil and borage in terms of weeding and no weed controls per replicates were used. Each plot was included 5 rows of medicinal plants. Cover crop inter-seeded simultaneously in the main crop. Estimation of leaf area and dry matter of each plant in different canopy layers (0-20, 20-40, 40-60, 80.100, 100-120 and 120-140 cm were done after 75 planting days, with 1 m × 1 m quadrate per plot. For this purpose a vertical card board frame marked in 20-cm increments was used in the field as a guide to cut standing plants (crops, cover crops and weeds into 20-cm strata increments (Mosier & Oliver, 1995. All samples were transferred to the

Emergency and elective implantation of covered stent systems in iatrogenic arterial injuries

International Nuclear Information System (INIS)

Goltz, J.P.; Kickuth, R.; Bastuerk, P.; Hoppe, H.; Triller, J.

2011-01-01

Purpose: To evaluate the effectiveness and safety of covered stents for the management of iatrogenic arterial injury. Materials and Methods: Between 03/1998 and 12/2009, 31 patients underwent selective covered stent implantation after iatrogenic arterial injury. 12/31 of these patients (38.7 %) were hemodynamically unstable. Six different endovascular covered stent types were utilized. The primary endpoints of this study were technical and clinical success and rates of minor and major complications. Results: Initial angiograms demonstrated active extravasation in 19 (61.3 %) patients and pseudoaneurysms in 12 (38.7 %) patients. The following sites of bleeding origin were detected: axillary artery, subclavian artery, common iliac artery, external iliac artery, internal iliac artery, common femoral artery, superficial femoral artery, popliteal and fibular artery, femoro-popliteal and popliteo-crural bypasses, common hepatic artery, aberrant hepatic artery, cystic and gastroduodenal artery. In all patients bleeding was effectively controlled by covered stent implantation resulting in an immediate technical success of 100 %. Clinical success attributed to covered stent implantation was documented in 30 of the 31 patients (96.8 %). Major complications included death in four patients (11.1 %), acute thrombosis with arm ischemia in one patient (2.8 %) and stent fracture with associated pseudoaneurysm in another patient (2.8 %). In 2/31 patients (6.5 %) covered stent failure was detected and successfully treated by implantation of a second covered stent. Conclusion: Emergency and elective implantation of covered stents may be used for minimally invasive and effective management of iatrogenic arterial injury. (orig.)

Forest cover of Champaign County, Illinois in 1993

Science.gov (United States)

Jesus Danilo Chinea; Louis R. Iverson

1997-01-01

The forest cover of Champaign County, in east-central Illinois, was mapped from 1993 aerial photography and entered in a geographical information system database. One hundred and six forest patches cover 3,380 ha. These patches have a mean area of 32 ha, a mean perimeter of 4,851 m, a mean perimeter to area ratio of 237, a fractal dimension of 1.59, and a mean nearest...

Mapping land cover through time with the Rapid Land Cover Mapper—Documentation and user manual

Science.gov (United States)

Cotillon, Suzanne E.; Mathis, Melissa L.

2017-02-15

The Rapid Land Cover Mapper is an Esri ArcGIS® Desktop add-in, which was created as an alternative to automated or semiautomated mapping methods. Based on a manual photo interpretation technique, the tool facilitates mapping over large areas and through time, and produces time-series raster maps and associated statistics that characterize the changing landscapes. The Rapid Land Cover Mapper add-in can be used with any imagery source to map various themes (for instance, land cover, soils, or forest) at any chosen mapping resolution. The user manual contains all essential information for the user to make full use of the Rapid Land Cover Mapper add-in. This manual includes a description of the add-in functions and capabilities, and step-by-step procedures for using the add-in. The Rapid Land Cover Mapper add-in was successfully used by the U.S. Geological Survey West Africa Land Use Dynamics team to accurately map land use and land cover in 17 West African countries through time (1975, 2000, and 2013).

Development of 2010 national land cover database for the Nepal.

Science.gov (United States)

Uddin, Kabir; Shrestha, Him Lal; Murthy, M S R; Bajracharya, Birendra; Shrestha, Basanta; Gilani, Hammad; Pradhan, Sudip; Dangol, Bikash

2015-01-15

Land cover and its change analysis across the Hindu Kush Himalayan (HKH) region is realized as an urgent need to support diverse issues of environmental conservation. This study presents the first and most complete national land cover database of Nepal prepared using public domain Landsat TM data of 2010 and replicable methodology. The study estimated that 39.1% of Nepal is covered by forests and 29.83% by agriculture. Patch and edge forests constituting 23.4% of national forest cover revealed proximate biotic interferences over the forests. Core forests constituted 79.3% of forests of Protected areas where as 63% of area was under core forests in the outside protected area. Physiographic regions wise forest fragmentation analysis revealed specific conservation requirements for productive hill and mid mountain regions. Comparative analysis with Landsat TM based global land cover product showed difference of the order of 30-60% among different land cover classes stressing the need for significant improvements for national level adoption. The online web based land cover validation tool is developed for continual improvement of land cover product. The potential use of the data set for national and regional level sustainable land use planning strategies and meeting several global commitments also highlighted. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of deforestation and land cover database for Bhutan (1930-2014).

Science.gov (United States)

Reddy, C Sudhakar; Satish, K V; Jha, C S; Diwakar, P G; Murthy, Y V N Krishna; Dadhwal, V K

2016-12-01

Bhutan is a mountainous country located in the Himalayan biodiversity hotspot. This study has quantified the total area under land cover types, estimated the rate of forest cover change, analyzed the changes across forest types, and modeled forest cover change hotpots in Bhutan. The topographical maps and satellite remote sensing images were analyzed to get the spatial patterns of forest and associated land cover changes over the past eight decades (1930-1977-1987-1995-2005-2014). Forest is the largest land cover in Bhutan and constitutes 68.3% of the total geographical area in 2014. Subtropical broad leaved hill forest is predominant type occupies 34.1% of forest area in Bhutan, followed by montane dry temperate (20.9%), montane wet temperate (18.9%), Himalayan moist temperate (10%), and tropical moist sal (8.1%) in 2014. The major forest cover loss is observed in subtropical broad leaved hill forest (64.5 km 2 ) and moist sal forest (9.9 km 2 ) from 1977 to 2014. The deforested areas have mainly been converted into agriculture and contributed for 60.9% of forest loss from 1930 to 2014. In spite of major decline of forest cover in time interval of 1930-1977, there is no net rate of deforestation is recorded in Bhutan since 1995. Forest cover change analysis has been carried out to evaluate the conservation effectiveness in "Protected Areas" of Bhutan. Hotspots that have undergone high transformation in forest cover for afforestation and deforestation were highlighted in the study for conservation prioritisation. Forest conservation policies in Bhutan are highly effective in controlling deforestation as compared to neighboring Asian countries and such service would help in mitigating climate change.

Evaluation and parameterization of ATCOR3 topographic correction method for forest cover mapping in mountain areas

Science.gov (United States)

Balthazar, Vincent; Vanacker, Veerle; Lambin, Eric F.

2012-08-01

A topographic correction of optical remote sensing data is necessary to improve the quality of quantitative forest cover change analyses in mountainous terrain. The implementation of semi-empirical correction methods requires the calibration of model parameters that are empirically defined. This study develops a method to improve the performance of topographic corrections for forest cover change detection in mountainous terrain through an iterative tuning method of model parameters based on a systematic evaluation of the performance of the correction. The latter was based on: (i) the general matching of reflectances between sunlit and shaded slopes and (ii) the occurrence of abnormal reflectance values, qualified as statistical outliers, in very low illuminated areas. The method was tested on Landsat ETM+ data for rough (Ecuadorian Andes) and very rough mountainous terrain (Bhutan Himalayas). Compared to a reference level (no topographic correction), the ATCOR3 semi-empirical correction method resulted in a considerable reduction of dissimilarities between reflectance values of forested sites in different topographic orientations. Our results indicate that optimal parameter combinations are depending on the site, sun elevation and azimuth and spectral conditions. We demonstrate that the results of relatively simple topographic correction methods can be greatly improved through a feedback loop between parameter tuning and evaluation of the performance of the correction model.

Variation in wood anatomy of species with a distribution covering both rain forest and savanna areas of the Ivory Coast, West-Africa

NARCIS (Netherlands)

Outer, den R.W.; Veenendaal, van W.L.H.

1976-01-01

The variation in wood anatomy within 30 hardwood species, each with a distribution covering both rain forest and savanna areas of the Ivory Coast, Africa, has been studied. Compared to specimens from the rain forest, material from the savanna tends to have more wood ray tissue (rays are higher,

About soil cover heterogeneity of agricultural research stations' experimental fields

Science.gov (United States)

Rannik, Kaire; Kõlli, Raimo; Kukk, Liia

2013-04-01

Depending on local pedo-ecological conditions (topography, (geo) diversity of soil parent material, meteorological conditions) the patterns of soil cover and plant cover determined by soils are very diverse. Formed in the course of soil-plant mutual relationship, the natural ecosystems are always influenced to certain extent by the other local soil forming conditions or they are site specific. The agricultural land use or the formation of agro-ecosystems depends foremost on the suitability of soils for the cultivation of feed and food crops. As a rule, the most fertile or the best soils of the area, which do not present any or present as little as possible constraints for agricultural land use, are selected for this purpose. Compared with conventional field soils, the requirements for the experimental fields' soil cover quality are much higher. Experimental area soils and soil cover composition should correspond to local pedo-ecological conditions and, in addition to that, represent the soil types dominating in the region, whereas the fields should be as homogeneous as possible. The soil cover heterogeneity of seven arable land blocks of three research stations (Jõgeva, Kuusiku and Olustvere) was studied 1) by examining the large scale (1:10 000) digital soil map (available via the internet), and 2) by field researches using the transect method. The stages of soils litho-genetic and moisture heterogeneities were estimated by using the Estonian normal soils matrix, however, the heterogeneity of top- and subsoil texture by using the soil texture matrix. The quality and variability of experimental fields' soils humus status, was studied more thoroughly from the aspect of humus concentration (g kg-1), humus cover thickness (cm) and humus stocks (Mg ha-1). The soil cover of Jõgeva experimental area, which presents an accumulative drumlin landscape (formed during the last glacial period), consist from loamy Luvisols and associated to this Cambisols. In Kuusiku area

Temporary placement of covered retrievable expandable nitinol stents with barbs in high-risk surgical patients with benign prostatic hyperplasia: work in progress.

Science.gov (United States)

Kim, Choung-Soo; Song, Ho-Young; Jeong, In Gab; Yeo, Hyun Jin; Kim, Eun-Young; Park, Jung-Hoon; Yoon, Chang Jin; Paick, Sung Hyun; Park, Sang Woo; Bae, Jae-Ik; Won, Je Hwan

2011-10-01

To report the use of a newly constructed, covered, retrievable, expandable nitinol stent with barbs to overcome the problem of stent migration associated with conventional covered prostatic expandable stents and to evaluate prospectively the technical feasibility and clinical effectiveness of the stents in patients with benign prostatic hyperplasia (BPH). A covered retrievable expandable nitinol stent with four barbs was placed with use of an 18-F stent delivery system in seven consecutive patients with symptomatic BPH who had high operative risks. Age range of patients was 62-83 years (mean 74 years). In cases in which the stent migrated, it was replaced with a stent with eight barbs. The stents were routinely removed 4 months after placement using a 21-F stent removal set. Stent placement was technically successful and well tolerated in six of the seven patients. The remaining patient needed a second stent placement after removal of the first stent. The stent with four barbs migrated into the urinary bladder in four patients (57%); three of these patients received a second stent with eight barbs with good results, and the fourth patient did not need further treatment because his symptoms improved. Routine removal of the stent 4 months after placement was performed in three of the seven patients with good results. Retrievable stents with eight barbs seem to overcome the problem of stent migration associated with conventional prostatic expandable stents. Preliminary results suggest that stents with barbs are both feasible and effective in patients with BPH. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

Anticonvulsant prescription patterns in patients covered by the Colombian Health System.

Science.gov (United States)

Morales-Plaza, C D; Machado-Alba, J E

Epilepsy is a group of long-term neurological disorders characterised by seizures that may respond to pharmacological treatment. Determine the prescribing patterns of anticonvulsants for patients covered by the healthcare system in Colombia. Cross-sectional study using a database containing 6.5 million people. From among residents in 88 Colombian cities, we selected patients of both sexes and all ages who were treated continuously with anticonvulsants between June and August 2012. We designed a drug consumption database and performed multivariate analysis for combination treatment and co-medication using SPSS 20.0. A total of 13,793 patients with mean age of 48.9±22.0 years were studied; 52.9% of the participants were women. Of the patient total, 74.4% were treated in monotherapy and 25.6% received two or more anticonvulsants. Globally, 72.9% of the patients were initially treated with classic anticonvulsants and 27.1% with new drugs. The most frequently used drugs were valproic acid (33.3%), carbamazepine (30.2%), clonazepam (15.7%), pregabalin (10.3%), phenytoin (10.0%) and levetiracetam (7.9%). Most agents were used in higher doses than recommended. The most common combinations were valproic acid+clonazepam (10.9%), valproic acid+carbamazepine (10.0%), carbamazepine+clonazepam (5.6%), valproic acid+phenytoin (4.4%). The most frequently prescribed co-medications were antihypertensives (61.0%), lipid-lowering drugs (45.8%), antidepressants (36.7%), antipsychotics (20.1%), anxiolytics (7.9%), and lithium (1.8%). Doctors predominantly prescribe drugs with a high therapeutic value and favour anticonvulsant monotherapy. Most agents were used in higher doses than recommended. This underlines the need to design educational strategies addressing these prescribing habits, and to undertake research on the effectiveness of treatment. Copyright © 2014 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Tracking Land Use/Land Cover Dynamics in Cloud Prone Areas Using Moderate Resolution Satellite Data: A Case Study in Central Africa

Directory of Open Access Journals (Sweden)

Bikash Basnet

2015-05-01

Full Text Available Tracking land surface dynamics over cloud prone areas with complex mountainous terrain is an important challenge facing the Earth Science community. One such region is the Lake Kivu region in Central Africa. We developed a processing chain to systematically monitor the spatio-temporal land use/land cover dynamics of this region over the years 1988, 2001, and 2011 using Landsat data, complemented by ancillary data. Topographic compensation was performed on Landsat reflectances to avoid the strong illumination angle impacts and image compositing was used to compensate for frequent cloud cover and thus incomplete annual data availability in the archive. A systematic supervised classification was applied to the composite Landsat imagery to obtain land cover thematic maps with overall accuracies of 90% and higher. Subsequent change analysis between these years found extensive conversions of the natural environment as a result of human related activities. The gross forest cover loss for 1988–2001 and 2001–2011 period was 216.4 and 130.5 thousand hectares, respectively, signifying significant deforestation in the period of civil war and a relatively stable and lower deforestation rate later, possibly due to conservation and reforestation efforts in the region. The other dominant land cover changes in the region were aggressive subsistence farming and urban expansion displacing natural vegetation and arable lands. Despite limited data availability, this study fills the gap of much needed detailed and updated land cover change information for this biologically important region of Central Africa. These multi-temporal datasets will be a valuable baseline for land use managers in the region interested in developing ecologically sustainable land management strategies and measuring the impacts of biodiversity conservation efforts.

Operational monitoring of land-cover change using multitemporal remote sensing data

Science.gov (United States)

Rogan, John

2005-11-01

Land-cover change, manifested as either land-cover modification and/or conversion, can occur at all spatial scales, and changes at local scales can have profound, cumulative impacts at broader scales. The implication of operational land-cover monitoring is that researchers have access to a continuous stream of remote sensing data, with the long term goal of providing for consistent and repetitive mapping. Effective large area monitoring of land-cover (i.e., >1000 km2) can only be accomplished by using remotely sensed images as an indirect data source in land-cover change mapping and as a source for land-cover change model projections. Large area monitoring programs face several challenges: (1) choice of appropriate classification scheme/map legend over large, topographically and phenologically diverse areas; (2) issues concerning data consistency and map accuracy (i.e., calibration and validation); (3) very large data volumes; (4) time consuming data processing and interpretation. Therefore, this dissertation research broadly addresses these challenges in the context of examining state-of-the-art image pre-processing, spectral enhancement, classification, and accuracy assessment techniques to assist the California Land-cover Mapping and Monitoring Program (LCMMP). The results of this dissertation revealed that spatially varying haze can be effectively corrected from Landsat data for the purposes of change detection. The Multitemporal Spectral Mixture Analysis (MSMA) spectral enhancement technique produced more accurate land-cover maps than those derived from the Multitemporal Kauth Thomas (MKT) transformation in northern and southern California study areas. A comparison of machine learning classifiers showed that Fuzzy ARTMAP outperformed two classification tree algorithms, based on map accuracy and algorithm robustness. Variation in spatial data error (positional and thematic) was explored in relation to environmental variables using geostatistical interpolation

Tree and impervious cover change in U.S

Science.gov (United States)

David J. Nowak; Eric J. Greenfield

2012-01-01

Paired aerial photographs were interpreted to assess recent changes in tree, impervious and other cover types in 20 U.S. cities as well as urban land within the conterminous United States. National results indicate that tree cover in urban areas of the United States is on the decline at a rate of about 7900 ha/yr or 4.0 million trees per year. Tree cover in 17 of the...

Comprehensive monitoring of Bangladesh tree cover inside and outside of forests, 2000-2014

Science.gov (United States)

Potapov, P.; Siddiqui, B. N.; Iqbal, Z.; Aziz, T.; Zzaman, B.; Islam, A.; Pickens, A.; Talero, Y.; Tyukavina, A.; Turubanova, S.; Hansen, M. C.

2017-10-01

A novel approach for satellite-based comprehensive national tree cover change assessment was developed and applied in Bangladesh, a country where trees outside of forests play an important role in the national economy and carbon sequestration. Tree cover change area was quantified using the integration of wall-to-wall Landsat-based mapping with a higher spatial resolution sample-based assessment. The total national tree canopy cover area was estimated as 3165 500 ± 186 600 ha in the year 2000, with trees outside forests making up 54% of total canopy cover. Total tree canopy cover increased by 135 700 (± 116 600) ha (4.3%) during the 2000-2014 time interval. Bangladesh exhibits a national tree cover dynamic where net change is rather small, but gross dynamics significant and variable by forest type. Despite the overall gain in tree cover, results revealed the ongoing clearing of natural forests, especially within the Chittagong hill tracts. While forests decreased their tree cover area by 83 600 ha, the trees outside forests (including tree plantations, village woodlots, and agroforestry) increased their canopy area by 219 300 ha. Our results demonstrated method capability to quantify tree canopy cover dynamics within a fine-scale agricultural landscape. Our approach for comprehensive monitoring of tree canopy cover may be recommended for operational implementation in Bangladesh and other countries with significant tree cover outside of forests.

Creating high-resolution time series land-cover classifications in rapidly changing forested areas with BULC-U in Google Earth Engine

Science.gov (United States)

Cardille, J. A.; Lee, J.

2017-12-01

With the opening of the Landsat archive, there is a dramatically increased potential for creating high-quality time series of land use/land-cover (LULC) classifications derived from remote sensing. Although LULC time series are appealing, their creation is typically challenging in two fundamental ways. First, there is a need to create maximally correct LULC maps for consideration at each time step; and second, there is a need to have the elements of the time series be consistent with each other, without pixels that flip improbably between covers due only to unavoidable, stray classification errors. We have developed the Bayesian Updating of Land Cover - Unsupervised (BULC-U) algorithm to address these challenges simultaneously, and introduce and apply it here for two related but distinct purposes. First, with minimal human intervention, we produced an internally consistent, high-accuracy LULC time series in rapidly changing Mato Grosso, Brazil for a time interval (1986-2000) in which cropland area more than doubled. The spatial and temporal resolution of the 59 LULC snapshots allows users to witness the establishment of towns and farms at the expense of forest. The new time series could be used by policy-makers and analysts to unravel important considerations for conservation and management, including the timing and location of past development, the rate and nature of changes in forest connectivity, the connection with road infrastructure, and more. The second application of BULC-U is to sharpen the well-known GlobCover 2009 classification from 300m to 30m, while improving accuracy measures for every class. The greatly improved resolution and accuracy permits a better representation of the true LULC proportions, the use of this map in models, and quantification of the potential impacts of changes. Given that there may easily be thousands and potentially millions of images available to harvest for an LULC time series, it is imperative to build useful algorithms

Fully covered stents versus partially covered stents for palliative treatment of esophageal cancer: Is there a difference?

Science.gov (United States)

Alonso Lárraga, J O; Flores Carmona, D Y; Hernández Guerrero, A; Ramírez Solís, M E; de la Mora Levy, J G; Sánchez Del Monte, J C

2018-02-26

Malignant dysphagia is difficulty swallowing resulting from esophageal obstruction due to cancer. The goal of palliative treatment is to reduce the dysphagia and improve oral dietary intake. Self-expandable metallic stents are the current treatment of choice, given that they enable the immediate restoration of oral intake. The aim of the present study was to describe the results of using totally covered and partially covered esophageal stents for palliating esophageal cancer. A retrospective study was conducted on patients with inoperable esophageal cancer treated with self-expandable metallic stents. The 2 groups formed were: group A, which consisted of patients with a fully covered self-expandable stent (SX-ELLA ® ), and group B, which was made up of patients with a partially covered self-expandable stent (Ultraflex ® ). Of the 69-patient total, 50 were included in the study. Group A had 19 men and 2 women and their mean age was 63.6 years (range 41-84). Technical success was achieved in 100% (n=21) of the cases and clinical success in 90.4% (n=19). Group B had 24 men and 5 women and their mean age was 67.5 years (range 43-92). Technical success was achieved in 100% (n=29) of the cases and clinical success in 89.6% (n=26). Complications were similar in both groups (33.3 vs. 51.7%). There was no difference between the 2 types of stent for the palliative treatment of esophageal cancer with respect to technical success, clinical success, or complications. Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

LAND COVER CHANGE MONITORING OF TYPICAL FUNCTIONAL COMMUNITIES OF SICHUAN PROVINCE BASED ON ZY-3 DATA

Directory of Open Access Journals (Sweden)

G. M. Li

2018-04-01

Full Text Available According to the function, land space types are divided into key development areas, restricted development areas and forbidden development areas in Sichuan Province. This paper monitors and analyses the changes of land cover in different typical functional areas from 2010 to 2017, which based on ZY-3 high-score images data and combined with statistical yearbook and thematic data of Sichuan Province. The results show that: The land cover types of typical key development zones are mainly composed of cultivated land, forest land, garden land, and housing construction land, which accounts for the total area of land cover 87 %. The land cover types of typical restricted development zone mainly consists of forest land and grassland, which occupy 97.71 % of the total area of the surface coverage. The land cover types of the typical prohibition development zone mainly consist of forest land, grassland, desert and bared earth, which accounts for the total area of land cover 99.31 %.

Land Cover Change Monitoring of Typical Functional Communities of Sichuan Province Based on ZY-3 Data

Science.gov (United States)

Li, G. M.; Li, S.; Ying, G. W.; Wu, X. P.

2018-04-01

According to the function, land space types are divided into key development areas, restricted development areas and forbidden development areas in Sichuan Province. This paper monitors and analyses the changes of land cover in different typical functional areas from 2010 to 2017, which based on ZY-3 high-score images data and combined with statistical yearbook and thematic data of Sichuan Province. The results show that: The land cover types of typical key development zones are mainly composed of cultivated land, forest land, garden land, and housing construction land, which accounts for the total area of land cover 87 %. The land cover types of typical restricted development zone mainly consists of forest land and grassland, which occupy 97.71 % of the total area of the surface coverage. The land cover types of the typical prohibition development zone mainly consist of forest land, grassland, desert and bared earth, which accounts for the total area of land cover 99.31 %.

Differences in breeding bird assemblages related to reed canary grass cover cover and forest structure on the Upper Mississippi River

Science.gov (United States)

Kirsch, Eileen M.; Gray, Brian R.

2017-01-01

Floodplain forest of the Upper Mississippi River provides habitat for an abundant and diverse breeding bird community. However, reed canary grass Phalaris arundinacea invasion is a serious threat to the future condition of this forest. Reed canary grass is a well-known aggressive invader of wetland systems in the northern tier states of the conterminous United States. Aided by altered flow regimes and nutrient inputs from agriculture, reed canary grass has formed dense stands in canopy gaps and forest edges, retarding tree regeneration. We sampled vegetation and breeding birds in Upper Mississippi River floodplain forest edge and interior areas to 1) measure reed canary grass cover and 2) evaluate whether the breeding bird assemblage responded to differences in reed canary grass cover. Reed canary grass was found far into forest interiors, and its cover was similar between interior and edge sites. Bird assemblages differed between areas with more or less reed canary grass cover (.53% cover breakpoint). Common yellowthroat Geothlypis trichas, black-capped chickadee Parus atricapillus, and rose-breasted grosbeak Pheucticus ludovicianus were more common and American redstart Setophaga ruticilla, great crested flycatcher Myiarchus crinitus, and Baltimore oriole Icterus galbula were less common in sites with more reed canary grass cover. Bird diversity and abundance were similar between sites with different reed canary grass cover. A stronger divergence in bird assemblages was associated with ground cover ,15%, resulting from prolonged spring flooding. These sites hosted more prothonotary warbler Protonotaria citrea, but they had reduced bird abundance and diversity compared to other sites. Our results indicate that frequently flooded sites may be important for prothonotary warblers and that bird assemblages shift in response to reed canary grass invasion.

Quantifying environmental limiting factors on tree cover using geospatial data.

Science.gov (United States)

Greenberg, Jonathan A; Santos, Maria J; Dobrowski, Solomon Z; Vanderbilt, Vern C; Ustin, Susan L

2015-01-01

Environmental limiting factors (ELFs) are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1) Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2) How are the ELFs distributed spatially? 3) To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET) and PET minus precipitation (PET-P) as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4) environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

Long-term agricultural land-cover change and potential for cropland expansion in the former Virgin Lands area of Kazakhstan

DEFF Research Database (Denmark)

Kraemer, Roland; Prishchepov, Alexander; Müller, Daniel

2015-01-01

of Northern Kazakhstan. Further, we assessed the potential of currently idle cropland for re-cultivation. We reconstructed the cropland extent before and after the Virgin Lands Campaign using archival maps, and we mapped the agricultural land cover in the late Soviet and post-Soviet period using multi...... until 1990, as well as cropland contraction after 1990, occurred mainly in areas that were less favorable for agriculture. Cropland re-cultivation after 2000 was occurring on lands with relatively favorable agro-environmental conditions in comparison to remaining idle croplands, albeit with much lower...... agro-environmental endowment compared to stable croplands from 1990 to 2010. In sum, we found that cropland production potentials of the currently uncultivated areas are much lower than commonly believed, and further cropland expansion is only possible at the expense of marginal lands. Our results...

Land Use and Land Cover Change Analysis along the Coastal ...

African Journals Online (AJOL)

Agribotix GCS 077

are carried out on the land usually effect changes in its cover. ... The FAO document on land cover classification systems, (2000) partly answers this ... over the surface land, including water, vegetation, bare soils and or artificial structures. ... diseases may occur more readily in areas exposed by Land Use and Land Cover ...

Soundscape and the Adaptation of Soundscape to Covered Spaces

Directory of Open Access Journals (Sweden)

Aslı ÖZÇEVİK

2011-01-01

Full Text Available Soundscape, as urban noise is termed, is essentially a qualitative approach which aims to discover ways to improve the “sonic environment”. A possible analogy can be assumed for the acoustic quality of some types of covered spaces which have a function similar to urban spaces. Furthermore, it can be proposed that such covered spaces may have a specific, distinct and recognizable sound environment - hence, a “soundscape” occurs which is created both by the architecture and the sound sources. This study takes a further step in suggesting that the acoustic comfort or sound quality of these spaces cannot be sufficiently dealt with via noise parameters. This paper aims to show the possibility of evaluating the acoustical quality of covered spaces, such as shopping centers, through soundscape studies. The formation of streets is the basic spatial design concept that connects open and closed shopping areas. For this reason the researchers chose to study a modern and an historical shopping center and a modern and a traditional street, both of which have shopping as a basic function, The soundscapes of these open and closed shopping areas were determined by soundwalks and listening tests. The objective and subjective findings of this study showed that covered shopping areas have a specific soundscape that can be evaluated by the soundwalk method regardless of whether the environment is open or covered.

Inventory and change detection of urban land cover in Illinois using Landsat Thematic Mapper data

International Nuclear Information System (INIS)

Cook, E.A.; Iverson, L.R.

1991-01-01

In order to provide information about urban forests and other vegetative land cover in Illinois cities, Landsat TM data from June 17, 1988, were classified for the Chicago metropolitan region and five urban areas of central Illinois. Ten land cover classes were identified, including three types of forestland, cropland, two grassland categories, two urban classes, water, and miscellaneous vegetation. The cities inventoried have a significantly higher proportion of forests and forested residential areas than the surrounding rural areas because of preservation measures and accruement of tree cover from landscaping. Short-term change in land cover for the Chicago region was also assessed by postclassification comparison of the 1988 data with similarly derived data from a June 3, 1985, TM scene. The largest single category of change in the six-county area was cropland to urban land use. A majority of cover loss was conversion of forested tracts to residential areas, and forest cover increase was negligible. 16 refs

Cover times of random searches

Science.gov (United States)

Chupeau, Marie; Bénichou, Olivier; Voituriez, Raphaël

2015-10-01

How long must one undertake a random search to visit all sites of a given domain? This time, known as the cover time, is a key observable to quantify the efficiency of exhaustive searches, which require a complete exploration of an area and not only the discovery of a single target. Examples range from immune-system cells chasing pathogens to animals harvesting resources, from robotic exploration for cleaning or demining to the task of improving search algorithms. Despite its broad relevance, the cover time has remained elusive and so far explicit results have been scarce and mostly limited to regular random walks. Here we determine the full distribution of the cover time for a broad range of random search processes, including Lévy strategies, intermittent strategies, persistent random walks and random walks on complex networks, and reveal its universal features. We show that for all these examples the mean cover time can be minimized, and that the corresponding optimal strategies also minimize the mean search time for a single target, unambiguously pointing towards their robustness.

The managed clearing: An overlooked land-cover type in urbanizing regions?

Science.gov (United States)

Madden, Marguerite; Gray, Josh; Meentemeyer, Ross K.

2018-01-01

Urban ecosystem assessments increasingly rely on widely available map products, such as the U.S. Geological Service (USGS) National Land Cover Database (NLCD), and datasets that use generic classification schemes to detect and model large-scale impacts of land-cover change. However, utilizing existing map products or schemes without identifying relevant urban class types such as semi-natural, yet managed land areas that account for differences in ecological functions due to their pervious surfaces may severely constrain assessments. To address this gap, we introduce the managed clearings land-cover type–semi-natural, vegetated land surfaces with varying degrees of management practices–for urbanizing landscapes. We explore the extent to which managed clearings are common and spatially distributed in three rapidly urbanizing areas of the Charlanta megaregion, USA. We visually interpreted and mapped fine-scale land cover with special attention to managed clearings using 2012 U.S. Department of Agriculture (USDA) National Agriculture Imagery Program (NAIP) images within 150 randomly selected 1-km2 blocks in the cities of Atlanta, Charlotte, and Raleigh, and compared our maps with National Land Cover Database (NLCD) data. We estimated the abundance of managed clearings relative to other land use and land cover types, and the proportion of land-cover types in the NLCD that are similar to managed clearings. Our study reveals that managed clearings are the most common land cover type in these cities, covering 28% of the total sampled land area– 6.2% higher than the total area of impervious surfaces. Managed clearings, when combined with forest cover, constitutes 69% of pervious surfaces in the sampled region. We observed variability in area estimates of managed clearings between the NAIP-derived and NLCD data. This suggests using high-resolution remote sensing imagery (e.g., NAIP) instead of modifying NLCD data for improved representation of spatial heterogeneity and

Study on resources and environmental data integration towards data warehouse construction covering trans-boundary area of China, Russia and Mongolia

Science.gov (United States)

Wang, J.; Song, J.; Gao, M.; Zhu, L.

2014-02-01

The trans-boundary area between Northern China, Mongolia and eastern Siberia of Russia is a continuous geographical area located in north eastern Asia. Many common issues in this region need to be addressed based on a uniform resources and environmental data warehouse. Based on the practice of joint scientific expedition, the paper presented a data integration solution including 3 steps, i.e., data collection standards and specifications making, data reorganization and process, data warehouse design and development. A series of data collection standards and specifications were drawn up firstly covering more than 10 domains. According to the uniform standard, 20 resources and environmental survey databases in regional scale, and 11 in-situ observation databases were reorganized and integrated. North East Asia Resources and Environmental Data Warehouse was designed, which included 4 layers, i.e., resources layer, core business logic layer, internet interoperation layer, and web portal layer. The data warehouse prototype was developed and deployed initially. All the integrated data in this area can be accessed online.

Study on resources and environmental data integration towards data warehouse construction covering trans-boundary area of China, Russia and Mongolia

International Nuclear Information System (INIS)

Wang, J; Song, J; Gao, M; Zhu, L

2014-01-01

The trans-boundary area between Northern China, Mongolia and eastern Siberia of Russia is a continuous geographical area located in north eastern Asia. Many common issues in this region need to be addressed based on a uniform resources and environmental data warehouse. Based on the practice of joint scientific expedition, the paper presented a data integration solution including 3 steps, i.e., data collection standards and specifications making, data reorganization and process, data warehouse design and development. A series of data collection standards and specifications were drawn up firstly covering more than 10 domains. According to the uniform standard, 20 resources and environmental survey databases in regional scale, and 11 in-situ observation databases were reorganized and integrated. North East Asia Resources and Environmental Data Warehouse was designed, which included 4 layers, i.e., resources layer, core business logic layer, internet interoperation layer, and web portal layer. The data warehouse prototype was developed and deployed initially. All the integrated data in this area can be accessed online

Optimal shortening of uniform covering arrays.

Directory of Open Access Journals (Sweden)

Jose Torres-Jimenez

Full Text Available Software test suites based on the concept of interaction testing are very useful for testing software components in an economical way. Test suites of this kind may be created using mathematical objects called covering arrays. A covering array, denoted by CA(N; t, k, v, is an N × k array over [Formula: see text] with the property that every N × t sub-array covers all t-tuples of [Formula: see text] at least once. Covering arrays can be used to test systems in which failures occur as a result of interactions among components or subsystems. They are often used in areas such as hardware Trojan detection, software testing, and network design. Because system testing is expensive, it is critical to reduce the amount of testing required. This paper addresses the Optimal Shortening of Covering ARrays (OSCAR problem, an optimization problem whose objective is to construct, from an existing covering array matrix of uniform level, an array with dimensions of (N - δ × (k - Δ such that the number of missing t-tuples is minimized. Two applications of the OSCAR problem are (a to produce smaller covering arrays from larger ones and (b to obtain quasi-covering arrays (covering arrays in which the number of missing t-tuples is small to be used as input to a meta-heuristic algorithm that produces covering arrays. In addition, it is proven that the OSCAR problem is NP-complete, and twelve different algorithms are proposed to solve it. An experiment was performed on 62 problem instances, and the results demonstrate the effectiveness of solving the OSCAR problem to facilitate the construction of new covering arrays.

Exploring patient satisfaction levels, self-rated oral health status and associated variables among citizens covered for dental insurance through a National Social Security Scheme in India.

Science.gov (United States)

Singh, Abhinav; Purohit, Bharathi M

2017-06-01

To assess patient satisfaction, self-rated oral health and associated factors, including periodontal status and dental caries, among patients covered for dental insurance through a National Social Security Scheme in New Delhi, India. A total of 1,498 patients participated in the study. Satisfaction levels and self-rated oral-health scores were measured using a questionnaire comprising 12 closed-ended questions. Clinical data were collected using the Community Periodontal Index (CPI) and the decayed, missing and filled teeth (DMFT) index. Regression analysis was conducted to evaluate factors associated with dental caries, periodontal status and self-rated oral health. Areas of concern included poor cleanliness within the hospital, extensive delays for appointments, waiting time in hospital and inadequate interpersonal and communication skills among health-care professionals. Approximately 51% of the respondents rated their oral health as fair to poor. Younger age, no tobacco usage, good periodontal status and absence of dental caries were significantly associated with higher oral health satisfaction, with odds ratios of 3.94, 2.38, 2.58 and 2.09, respectively (P ≤ 0.001). The study indicates poor satisfaction levels with the current dental care system and a poor self-rated oral health status among the study population. Some specific areas of concern have been identified. These findings may facilitate restructuring of the existing dental services under the National Social Security Scheme towards creating a better patient care system. © 2017 FDI World Dental Federation.

Quantifying environmental limiting factors on tree cover using geospatial data.

Directory of Open Access Journals (Sweden)

Jonathan A Greenberg

Full Text Available Environmental limiting factors (ELFs are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1 Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2 How are the ELFs distributed spatially? 3 To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET and PET minus precipitation (PET-P as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4 environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover < 25% were primarily limited by cold mean temperatures, open-canopy forest sites (tree cover between 25% and 60% were primarily limited by evaporative demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

Land Cover Change Detection in Urban Lake Areas Using Multi-Temporary Very High Spatial Resolution Aerial Images

Directory of Open Access Journals (Sweden)

Wenyuan Zhang

2018-01-01

Full Text Available The availability of very high spatial resolution (VHR remote sensing imagery provides unique opportunities to exploit meaningful change information in detail with object-oriented image analysis. This study investigated land cover (LC changes in Shahu Lake of Wuhan using multi-temporal VHR aerial images in the years 1978, 1981, 1989, 1995, 2003, and 2011. A multi-resolution segmentation algorithm and CART (classification and regression trees classifier were employed to perform highly accurate LC classification of the individual images, while a post-classification comparison method was used to detect changes. The experiments demonstrated that significant changes in LC occurred along with the rapid urbanization during 1978–2011. The dominant changes that took place in the study area were lake and vegetation shrinking, replaced by high density buildings and roads. The total area of Shahu Lake decreased from ~7.64 km2 to ~3.60 km2 during the past 33 years, where 52.91% of its original area was lost. The presented results also indicated that urban expansion and inadequate legislative protection are the main factors in Shahu Lake’s shrinking. The object-oriented change detection schema presented in this manuscript enables us to better understand the specific spatial changes of Shahu Lake, which can be used to make reasonable decisions for lake protection and urban development.

A neonatal screening of congenital hypothyroidism covered 266 401 cases in Tianjin area

International Nuclear Information System (INIS)

Fang Peihua; Lv Mei; Huang Guangyu; Yuan Chengyun; Xu Jing; Yang Qingyan; Wang Xiuying; Ma Xiancheng; Liu Geli; Chen Kunming; Zhang Moling

2003-01-01

Objective: To observe the incidence, the curative rate and the long term prognosis of congenital hypothyroidism (CH) newborns detected by screening program in Tianjin area initiated at the beginning of 1982. Methods: Primarily, the T 4 and thyroid-stimulating hormone (TSH) radioimmunoassay (RIA) of dried blood sample on filter paper developed in our laboratory were used. The TSH RIA was replaced by a time-resolved fluorescence immunoassay (Tr-FIA) in 1998. The primary T 4 RIA was replaced by a commercial kit for T 4 RIA in 1999. SPECT imaging on thyroid was performed after intravenous administration of 99 Tc m O 4 - 11.1-18.5 MBq. Results: A total of 266 401 neonates was screened for CH in our laboratory in Tianjin area. 36 cases of permanent CH were confirmed in the program. The incidence of CH was 0.014%; 22 cases of CH here were kept in treatment . Of the 22 cases, 19 cases were recalled in 2000, 18 of them (94.7%) showed currently with normal growth and development in the check-up. Imaging on thyroid ( 99 Tc m ): among 19 patients with CH, 1 case was found with normal gland, 1 with a hypogenetic thyroid, 3 cases with enlarged thyroid, 7 with ectopic gland, and the remaining 7 cases didn't show any image of thyroid. The bone age of 20 CH children was evaluated with the X ray radiography. In 6 cases of them, the bone age was normal, and 7 cases had progressed from development delay to normal. So far, retarded bone age of the remaining 7 CH patients didn't show any renewing yet. The bone age renewal was found in 3 younger children of them, but for the other 3 cases (9-12 years old) of CH patients with thyroid gland absence, the renewal of bone age was slower. Intelligence quotient (IQ) in 16 cases was measured. The scores of IQ in 13 cases of them (81.3%) were 80-119, 2 cases 72-77, 1 case 60. IQs of 6/16 cases of CH patients with thyroid absence were lower. May be it related to that, their hypothyroidism during fetal life was severer. Conclusions: Neonatal

Usefulness of flexible covered stent in malignant colorectal obstruction

Energy Technology Data Exchange (ETDEWEB)

Kang, Jee Hee; Kang, Sung Gwon; Kim, Hyung Jin; Noh, Hong Gi; Woo, Jae Hong; Suh, Chang Hae [Inha Univ. Hospital, Inchon (Korea, Republic of)

1998-07-01

To evaluate the usefulness of flexible covered stent in the treatment of acute colorectal obstruction secondary to colorectal carcinoma. Materials and Methods : Flexible covered stents were placed in 11 patients with clinical and radiologic signs of acute colonic obstruction secondary to colorectal carcinoma. The purposes of stent insertion were pre-operative bowel preparation in seven patients and palliative treatment in four. A fistula was present in two;in one this was between the proximal jejunum and colon, and the other was rectovaginal. The usefulness of stent insertion for the purpose of preoperative bowel preparation was evaluated according to the feasibility and status of bowel preparation, as decided by the operator. Palliative treatment for the relief of symptoms of acute bowel obstruction was evaluated according to the number and amount of defecation,bowel dilatation in simple abdomen radiography, and the presence of complications. Results : Bowel preparation for the purpose of preoperative bowel cleansing was easy in seven patients;the fecal materials remaining in the colon presented no problems during surgery. In one of four patients palliative treatment involved a colostomy;this was due to recurrent stent obstruction by fecal materials after three months, and in two other patients there was stent obstruction after two and five months, respectively. The stent in one of four patients who underwent palliative treatment was removed because of stent migration three days after insertion;the stents in two patients with fistulas covered the fistulas successfully. Complications after stent insertion were anal pain in three patients, anal bleeding in three and stent migration in one. Conclusion : The flexible covered stent was an effective device for the relief of acute colonic obstruction secondary to malignant rectosigmoid neoplasia. It allowed for single-stage operation and covered the fistula. We believe however that for further evaluation of the

Tree cover, tree height and bare soil cover differences along a land use degradation gradient in semi-arid savannas, South Africa

CSIR Research Space (South Africa)

Mathieu, R

2009-07-01

Full Text Available High resolution airborne hyperspectral and discrete return LiDAR data were used to assess bare soil and tree cover differences along a land use transect consisting of state-owned, privately-owned conservation areas, and communal areas in South...

Land cover change impact on urban flood modeling (case study: Upper Citarum watershed)

Science.gov (United States)

Siregar, R. I.

2018-03-01

The upper Citarum River watershed utilizes remote sensing technology in Geographic Information System to provide information on land coverage by interpretation of objects in the image. Rivers that pass through urban areas will cause flooding problems causing disadvantages, and it disrupts community activities in the urban area. Increased development in a city is related to an increase in the number of population growth that added by increasing quality and quantity of life necessities. Improved urban lifestyle changes have an impact on land cover. The impact in over time will be difficult to control. This study aims to analyze the condition of flooding in urban areas caused by upper Citarum watershed land-use change in 2001 with the land cover change in 2010. This modeling analyzes with the help of HEC-RAS to describe flooded inundation urban areas. Land cover change in upper Citarum watershed is not very significant; it based on the results of data processing of land cover has the difference of area that changed is not enormous. Land cover changes for the floods increased dramatically to a flow coefficient for 2001 is 0.65 and in 2010 at 0.69. In 2001, the inundation area about 105,468 hectares and it were about 92,289 hectares in 2010.

Ground cover in old-growth forests of the central hardwood region

Science.gov (United States)

Martin A. Spetich; Stephen R. Shifley; George R. Parker; Felix, Jr. Ponder

1997-01-01

Differences in ground cover (percent cover of litter, percent cover of vegetation and litter weight) in old-growth forests across this region are not well understood. We initiated a long-term study in a three-state region to enhance knowledge in this area. We present baseline results for ground cover and compare these data across productivity regions. Thirty 0.25-ac (0...

Cover design for radioactive and AMD-producing mine waste in the Ronneburg area, eastern Thuringia.

Science.gov (United States)

Gatzweiler, R; Jahn, S; Neubert, G; Paul, M

2001-01-01

At the former uranium mining site of Ronneburg, large scale underground and open pit mining for nearly 40 years resulted in a production of about 113,000 tonnes of uranium and about 200 million cubic metres of mine waste. In their present state, these materials cause risks to human health and strong environmental impacts and therefore demand remedial action. The remediation options available are relocation of mine spoil into the open pit and on site remediation by landscaping/contouring, placement of a cover and revegetation. A suitable vegetated cover system combined with a surface water drainage system provides long-term stability against erosion and reduces acid generation thereby meeting the main remediation objectives which are long-term reduction of radiological exposure and contaminant emissions and recultivation. The design of the cover system includes the evaluation of geotechnical, radiological, hydrological, geochemical and ecological criteria and models. The optimized overall model for the cover system has to comply with general conditions as, e.g. economic efficiency, public acceptance and sustainability. Most critical elements for the long-term performance of the cover system designed for the Beerwalde dump are the barrier system and its long-term integrity and a largely self-sustainable vegetation.

Estimating Accuracy of Land-Cover Composition From Two-Stage Clustering Sampling

Science.gov (United States)

Land-cover maps are often used to compute land-cover composition (i.e., the proportion or percent of area covered by each class), for each unit in a spatial partition of the region mapped. We derive design-based estimators of mean deviation (MD), mean absolute deviation (MAD), ...

Spatial Simulation Modelling of Future Forest Cover Change Scenarios in Luangprabang Province, Lao PDR

Directory of Open Access Journals (Sweden)

Khamma Homsysavath

2011-08-01

Full Text Available Taking Luangprabang province in Lao Peoples’s Democratic Republic (PDR as an example, we simulated future forest cover changes under the business-as-usual (BAU, pessimistic and optimistic scenarios based on the Markov-cellular automata (MCA model. We computed transition probabilities from satellite-derived forest cover maps (1993 and 2000 using the Markov chains, while the “weights of evidence” technique was used to generate transition potential maps. The initial forest cover map (1993, the transition potential maps and the 1993–2000 transition probabilities were used to calibrate the model. Forest cover simulations were then performed from 1993 to 2007 at an annual time-step. The simulated forest cover map for 2007 was compared to the observed (actual forest cover map for 2007 in order to test the accuracy of the model. Following the successful calibration and validation, future forest cover changes were simulated up to 2014 under different scenarios. The MCA simulations under the BAU and pessimistic scenarios projected that current forest areas would decrease, whereas unstocked forest areas would increase in the future. Conversely, the optimistic scenario projected that current forest areas would increase in the future if strict forestry laws enforcing conservation in protected forest areas are implemented. The three simulation scenarios provide a very good case study for simulating future forest cover changes at the subnational level (Luangprabang province. Thus, the future simulated forest cover changes can possibly be used as a guideline to set reference scenarios as well as undertake REDD/REDD+ preparedness activities within the study area.

Plastic-covered agriculture forces the regional climate to change

Science.gov (United States)

Yang, D.; Chen, J.; Chen, X.; Cao, X.

2016-12-01

The practice of plastic-covered agriculture as a solution to moderate the dilemma of global food shortage, meanwhile, brings great pressure to the local environment. This research was conducted to reveal the impacts of plastic-covered agritulture on regional climate change by experimenting in a plastic greenhouse (PG) dominated area - Weifang district, Shandong province, China. Based on a new plastic greenhouse index (PGI) proposed in this study, we reconstructed the spatial distribution of PG across 1995-2015 in the study area. With that, land surface temperature (LST) dataset combined with surface evapotranspiration, surface reflectance and precipitation data, was applied to the probe of PG's climatic impacts. Results showed that PG, in the study area, has experienced a striking spatial expansion during the past 20 years, and more important, the expansion correlated strongly to the local climate change. It showed that the annual precipitation, in the study area, decreased during these years, which constrasts to a slightly increasing trend of the adjacent districts without PG construction. In addition, resulting from the greenhouse effect, PG area presented a harsher increase of surface temperature compared to the non-PG areas. Our study also telled that the evapotranspiration of PG area has been largely cutted down ascribing to the gas tightness of plastic materials, showing a decline around 40%. This indicates a way that the development of plastic-covered agriculture may contribute to the change of the local climate.

Car Covers | Outdoor Covers Canada

OpenAIRE

Covers, Outdoor

2018-01-01

Protect your car from the elements with Ultimate Touch Car Cover. The multi-layer non-woven fabric is soft on the finish and offers 4 seasons all weather protection.https://outdoorcovers.ca/car-covers/

Inappropriate Dietary and Occupational Patterns: Major Risk Factors Associated With Brucellosis in the Area Covered by Karaj Health Center No. 2

Directory of Open Access Journals (Sweden)

Yosef Khani

2015-11-01

Full Text Available Background: Brucellosis is one of the most common diseases among humans and livestock. Using contaminated and unpasteurized dairy products, having contact with infected livestock and, in general, inappropriate dietary patterns, as well as lack of hygiene, can be noted as the most common modes of transmission for such a disease. Objectives: Since the establishment of Alborz province in Iran and, accordingly, Alborz university of medical sciences, Karaj, Iran, there has been no study on the epidemiological situation of the disease. Therefore, the present study examines the epidemiology of Brucellosis at Karaj Health center No. 2, Karaj, Iran, during 2011 - 2012. Patients and Methods: This research was a cross-sectional descriptive study, on patients with Brucellosis, during 2011 - 2012, in the area covered by Karaj health center No. 2, Karaj, Iran. The data about all suspected cases, collected from polyclinic, laboratories and health centers, and confirmed by Wright, combs Wright and 2ME tests were reviewed. After recording the demographic data and laboratory results, they were entered into STATA 11 software and analyzed. Results: The number of patients reported in this study was 67. The incidence of the disease during 2011 - 2012 was, respectively, 3.75 and 4.6 per hundred thousand and the average incidence of the disease was 4.2 per hundred thousand. The highest rate of infection, in terms of occupation, was found among ranchers (40.29%. In 100% of the cases, there was a history of consumption of cottage cheese, fresh cow milk or other unpasteurized dairy products. Considering the incidence season, most cases of the disease (38.80% had occurred in the spring. In terms of gender, 56.71% were male and 43.28% of patients were female. As well, in terms of age, more 50% of the patients were in the age groups of 31 - 40 and 41 - 50 years old. Conclusions: Given the occurrence of more cases of the disease among individuals with risk factors, such as

An automated approach for mapping persistent ice and snow cover over high latitude regions

Science.gov (United States)

Selkowitz, David J.; Forster, Richard R.

2016-01-01

We developed an automated approach for mapping persistent ice and snow cover (glaciers and perennial snowfields) from Landsat TM and ETM+ data across a variety of topography, glacier types, and climatic conditions at high latitudes (above ~65°N). Our approach exploits all available Landsat scenes acquired during the late summer (1 August–15 September) over a multi-year period and employs an automated cloud masking algorithm optimized for snow and ice covered mountainous environments. Pixels from individual Landsat scenes were classified as snow/ice covered or snow/ice free based on the Normalized Difference Snow Index (NDSI), and pixels consistently identified as snow/ice covered over a five-year period were classified as persistent ice and snow cover. The same NDSI and ratio of snow/ice-covered days to total days thresholds applied consistently across eight study regions resulted in persistent ice and snow cover maps that agreed closely in most areas with glacier area mapped for the Randolph Glacier Inventory (RGI), with a mean accuracy (agreement with the RGI) of 0.96, a mean precision (user’s accuracy of the snow/ice cover class) of 0.92, a mean recall (producer’s accuracy of the snow/ice cover class) of 0.86, and a mean F-score (a measure that considers both precision and recall) of 0.88. We also compared results from our approach to glacier area mapped from high spatial resolution imagery at four study regions and found similar results. Accuracy was lowest in regions with substantial areas of debris-covered glacier ice, suggesting that manual editing would still be required in these regions to achieve reasonable results. The similarity of our results to those from the RGI as well as glacier area mapped from high spatial resolution imagery suggests it should be possible to apply this approach across large regions to produce updated 30-m resolution maps of persistent ice and snow cover. In the short term, automated PISC maps can be used to rapidly

Hydrological impacts of global land cover change and human water use

Directory of Open Access Journals (Sweden)

J. H. C. Bosmans

2017-11-01

Full Text Available Human impacts on global terrestrial hydrology have been accelerating during the 20th century. These human impacts include the effects of reservoir building and human water use, as well as land cover change. To date, many global studies have focussed on human water use, but only a few focus on or include the impact of land cover change. Here we use PCR-GLOBWB, a combined global hydrological and water resources model, to assess the impacts of land cover change as well as human water use globally in different climatic zones. Our results show that land cover change has a strong effect on the global hydrological cycle, on the same order of magnitude as the effect of human water use (applying irrigation, abstracting water, for industrial use for example, including reservoirs, etc.. When globally averaged, changing the land cover from that of 1850 to that of 2000 increases discharge through reduced evapotranspiration. The effect of land cover change shows large spatial variability in magnitude and sign of change depending on, for example, the specific land cover change and climate zone. Overall, land cover effects on evapotranspiration are largest for the transition of tall natural vegetation to crops in energy-limited equatorial and warm temperate regions. In contrast, the inclusion of irrigation, water abstraction and reservoirs reduces global discharge through enhanced evaporation over irrigated areas and reservoirs as well as through water consumption. Hence, in some areas land cover change and water distribution both reduce discharge, while in other areas the effects may partly cancel out. The relative importance of both types of impacts varies spatially across climatic zones. From this study we conclude that land cover change needs to be considered when studying anthropogenic impacts on water resources.

The overall heat transfer of greenhouses covered with PE [polyethylene film] and PVC [polyvinyl chloride film] single layer: The heat insulation efficiency of greenhouses and their covering materials (1)

International Nuclear Information System (INIS)

Minagawa, H.; Tachibana, K.

1982-01-01

Overall heat transfer of polyethylene film (PE) and polyvinyl chloride film (PVC) were measured in the experimental greenhouses with hot-air heaters on the clear and on the cloudy nights during the period Nov. 1979 to Jan. 1980. Both films are 0.1 mm thick and have different physical properties for long-wave radiation. The heat insulation efficiency of the greenhouses covered with PE and PVC single layer was investigated, and the ratio of floor area to covering area for the experimental greenhouses, which is one of the indices for the heat insulation efficiency of greenhouses, was also taken into consideration. The results are as follows: 1. Using the ratio of the overall heat transfer and the overall heat transfer coefficients for the heat insulation efficiency, the PE-house revealed to be less efficient than the PVC-house. This can be due to PE being more transparent to long-wave radiation than PVC. The advantage in the PVC-house, however, decreased with the increasing of the inside-outside air temperature difference (Figs. 3 and 5). 2. The overall heat transfer coefficients of both greenhouses depended on the inside-outside temperature difference. As the temperature difference increased, the overall heat transfer coefficients decreased (Fig. 5). 3. The overall heat transfer coefficients of both greenhouses were smaller on the cloudy nights than that on the clear nights. When the condensation occurred at the interior film surface, the heat insulation efficiency of both greenhouses was increased, resulting in the decrease of the coefficient. The efficiency of the PE-house was more affected than the PVC-house when the condensation occurred (Figs. 6 and 7). 4. When the inside-outside air temperature difference was small, convective heat transferred from the outside air to the outside cover surface. With an increase in the inside-outside air temperature difference, convective heat flow occurred from the outside cover surface to the outside air. This phenomenon was

NLCD - MODIS land cover- albedo dataset for the continental United States

Data.gov (United States)

U.S. Environmental Protection Agency — The NLCD-MODIS land cover-albedo database integrates high-quality MODIS albedo observations with areas of homogeneous land cover from NLCD. The spatial resolution...

Fully covered self-expandable metal stents (SEMS), partially covered SEMS and self-expandable plastic stents for the treatment of benign esophageal ruptures and anastomotic leaks.

Science.gov (United States)

van Boeckel, Petra G A; Dua, Kulwinder S; Weusten, Bas L A M; Schmits, Ruben J H; Surapaneni, Naveen; Timmer, Robin; Vleggaar, Frank P; Siersema, Peter D

2012-02-29

Benign esophageal ruptures and anastomotic leaks are life-threatening conditions that are often treated surgically. Recently, placement of partially and fully covered metal or plastic stents has emerged as a minimally invasive treatment option. We aimed to determine the clinical effectiveness of covered stent placement for the treatment of esophageal ruptures and anastomotic leaks with special emphasis on different stent designs. Consecutive patients who underwent placement of a fully covered self-expandable metal stent (FSEMS), a partially covered SEMS (PSEMS) or a self-expanding plastic stent (SEPS) for a benign esophageal rupture or anastomotic leak after upper gastrointestinal surgery in the period 2007-2010 were included. Data on patient demographics, type of lesion, stent placement and removal, clinical success and complications were collected A total of 52 patients received 83 esophageal stents (61 PSEMS, 15 FSEMS, 7 SEPS) for an anastomotic leak (n=32), iatrogenic rupture (n=13), Boerhaave's syndrome (n=4) or other cause (n=3). Endoscopic stent removal was successful in all but eight patients treated with a PSEMS due to tissue ingrowth. Clinical success was achieved in 34 (76%, intention-to-treat: 65%) patients (PSEMS: 73%, FSEMS: 83%, SEPS: 83%) after a median of 1 (range 1-5) stent and a median stenting time of 39 (range 7-120) days. In total, 33 complications in 24 (46%) patients occurred (tissue in- or overgrowth (n=8), stent migration (n=10), ruptured stent cover (all Ultraflex; n=6), food obstruction (n=3), severe pain (n=2), esophageal rupture (n=2), hemorrhage (n=2)). One (2%) patient died of a stent-related cause. Covered stents placed for a period of 5-6 weeks may well be an alternative to surgery for treating benign esophageal ruptures or anastomotic leaks. As efficacy between PSEMS, FSEMS and SEPS is not different, stent choice should depend on expected risks of stent migration (SEPS and FSEMS) and tissue in- or overgrowth (PSEMS).

Forest Cover Estimation in Ireland Using Radar Remote Sensing: A Comparative Analysis of Forest Cover Assessment Methodologies

Science.gov (United States)

Devaney, John; Barrett, Brian; Barrett, Frank; Redmond, John; O`Halloran, John

2015-01-01

Quantification of spatial and temporal changes in forest cover is an essential component of forest monitoring programs. Due to its cloud free capability, Synthetic Aperture Radar (SAR) is an ideal source of information on forest dynamics in countries with near-constant cloud-cover. However, few studies have investigated the use of SAR for forest cover estimation in landscapes with highly sparse and fragmented forest cover. In this study, the potential use of L-band SAR for forest cover estimation in two regions (Longford and Sligo) in Ireland is investigated and compared to forest cover estimates derived from three national (Forestry2010, Prime2, National Forest Inventory), one pan-European (Forest Map 2006) and one global forest cover (Global Forest Change) product. Two machine-learning approaches (Random Forests and Extremely Randomised Trees) are evaluated. Both Random Forests and Extremely Randomised Trees classification accuracies were high (98.1–98.5%), with differences between the two classifiers being minimal (forest area and an increase in overall accuracy of SAR-derived forest cover maps. All forest cover products were evaluated using an independent validation dataset. For the Longford region, the highest overall accuracy was recorded with the Forestry2010 dataset (97.42%) whereas in Sligo, highest overall accuracy was obtained for the Prime2 dataset (97.43%), although accuracies of SAR-derived forest maps were comparable. Our findings indicate that spaceborne radar could aid inventories in regions with low levels of forest cover in fragmented landscapes. The reduced accuracies observed for the global and pan-continental forest cover maps in comparison to national and SAR-derived forest maps indicate that caution should be exercised when applying these datasets for national reporting. PMID:26262681

STRENGTHENING OF TRENCH COVER PLATES FOR SWITCHGEAR BUILDING

International Nuclear Information System (INIS)

M.S. RUBEN

2000-01-01

The objective of this calculation is to strengthen the existing trench cover plates of the Electrical Switchgear Building (BLDG 5010) of the Exploratory Studies Facility. A remodeling effort will change the portion of the facility that has the trenches for electrical cables to a craft/shop area. The users of the building will be using a forklift in this area (Clark CGP 30 forklift with a capacity of 3 tons). The trench covers require strengthening to support the wheel loads from the forklift. The output of this calculation will be sketches revising the floor plate details of DWG YMP-025-1-7007-ST103,2. (Details 4 and 5)

Full area covered 3D profile measurement of special-shaped optics based on a new prototype non-contact profiler.

Science.gov (United States)

Du, Hui-Lin; Zhou, Zhao-Zhong; Sun, Ze-Qing; Ju, Bing-Feng; Xu, Shaoning; Sun, Anyu

2017-06-01

A new prototype non-contact profiler based on surface tracking has been specially developed. Surface tracking is carried out by a specially designed dual stage probe system with the aid of a four-Degree Of Freedom high-precision motion platform. The dual stage probe system keeps a short-range optical probe constantly tracking the surface by a self-developed voice coil motor servo, by which a wide measuring range of up to 10 mm is realized. The system performance evaluation including resolution, repeatability, and scanning speed proved the good capability of the new prototype non-contact profiler. To realize a full area covered 3D profile measurement of special-shaped optics within one scanning procedure, a signal intensity monitor integrated in the surface tracking controller is specially developed. In the experiment, a snip-single-corner-rectangular-shaped freeform surface was successfully measured over full area by the new non-contact profiler. This work provides an effective solution for 3D profile measurement of special-shaped optical surfaces over full reflecting area. Experimental results demonstrate that the proposed measuring system is of great significance in quality evaluation of optical surfaces.

FP 6 EU - COVERS. Coordination action - VVER safety research

International Nuclear Information System (INIS)

Vasa, I.

2008-01-01

In this work research program of the European Union FP 6 - COVERS coordinated by the NRI Rez is presented. COVERS is designed to improve professional and communication environment in the specific area covering all aspects of safe and reliable operation of nuclear power plants with VVER-440 and VVER-1000 reactors. Project Consortium is composed of 26 research and development, engineering and technical support organisations of European VVER-operating and other EU and non-EU countries.

Evaluation of forest cover estimates for Haiti using supervised classification of Landsat data

Science.gov (United States)

Churches, Christopher E.; Wampler, Peter J.; Sun, Wanxiao; Smith, Andrew J.

2014-08-01

This study uses 2010-2011 Landsat Thematic Mapper (TM) imagery to estimate total forested area in Haiti. The thematic map was generated using radiometric normalization of digital numbers by a modified normalization method utilizing pseudo-invariant polygons (PIPs), followed by supervised classification of the mosaicked image using the Food and Agriculture Organization (FAO) of the United Nations Land Cover Classification System. Classification results were compared to other sources of land-cover data produced for similar years, with an emphasis on the statistics presented by the FAO. Three global land cover datasets (GLC2000, Globcover, 2009, and MODIS MCD12Q1), and a national-scale dataset (a land cover analysis by Haitian National Centre for Geospatial Information (CNIGS)) were reclassified and compared. According to our classification, approximately 32.3% of Haiti's total land area was tree covered in 2010-2011. This result was confirmed using an error-adjusted area estimator, which predicted a tree covered area of 32.4%. Standardization to the FAO's forest cover class definition reduces the amount of tree cover of our supervised classification to 29.4%. This result was greater than the reported FAO value of 4% and the value for the recoded GLC2000 dataset of 7.0%, but is comparable to values for three other recoded datasets: MCD12Q1 (21.1%), Globcover (2009) (26.9%), and CNIGS (19.5%). We propose that at coarse resolutions, the segmented and patchy nature of Haiti's forests resulted in a systematic underestimation of the extent of forest cover. It appears the best explanation for the significant difference between our results, FAO statistics, and compared datasets is the accuracy of the data sources and the resolution of the imagery used for land cover analyses. Analysis of recoded global datasets and results from this study suggest a strong linear relationship (R2 = 0.996 for tree cover) between spatial resolution and land cover estimates.

Covering and Reimbursing Telehealth Services.

Science.gov (United States)

Blackman, Kate

2016-01-01

Policymakers who are striving to achieve better health care, improved health outcomes and lower costs are considering new strategies and technologies. Telehealth is a tool that uses technology to provide health services remotely, and state leaders are looking to it now more than ever as a way to address workforce gaps and reach underserved patients. Among the challenges facing state lawmakers who are working to introduce or expand telehealth is how to handle covering patients and reimbursing providers.

Forest value and optimal rotations in continuous cover forestry

DEFF Research Database (Denmark)

Jacobsen, Jette Bredahl; Jensen, Frank; Thorsen, Bo Jellesmark

The Faustmann forest rotation model is a celebrated contribution in economics. The model provides a forest value expression and allows a solution to the optimal rotation problem valid for perpetual rotations of even-aged forest stands. However, continuous forest cover forest management systems......, but rigorous mathematical model of the continuous cover forest, which strictly focuses on the area use dynamics that such an uneven-aged forest must have in equilibrium. This implies explicitly accounting for area reallocation and for weighting the productivity of each age class by the area occupied. The model...... allows for a simple expression for forest value and the derivation of conditions for the optimal rotation age. The model also makes straightforward comparisons with the well-known Faustmann model possible. We present results for unrestricted as well as area-restricted versions of the models. We find...

Damped summer warming accompanied with cloud cover increase over Eurasia from 1982 to 2009

International Nuclear Information System (INIS)

Tang Qiuhong; Leng Guoyong

2012-01-01

The relationship between summer temperature, total cloud cover and precipitation over Eurasia was investigated using observation-based products of temperature and precipitation, and satellite-derived cloud cover and radiation products. We used a partial least squares regression approach to separate the local influences of cloud cover and precipitation on temperature variations. Our results suggest that the variance of summer temperature is partly explained by changes in summer cloudiness. The summer temperature dependence on cloud cover is strong at the high latitudes and in the middle latitude semi-humid area, while the dependence on precipitation is strong in the Central Asia arid area and the southern Asia humid area. During the period 1982–2009, the damped warming in extended West Siberia was accompanied with increases in cloud cover, and the pronounced warming in Europe and Mongolia was associated with a decrease in cloud cover and precipitation. Our results suggest that cloud cover may be the important local factor influencing the summer temperature variation in Eurasia while precipitation plays an important role at the middle latitudes. (letter)

Clinical observation of covered for malignant esophageal stricture and esophagus-bronchial fistula

International Nuclear Information System (INIS)

Luo Hailong; Lin Youen; Ye Zhi; Zhu Yifen

2010-01-01

Objective: To evaluate clinical value of self-expanded covered stents for advanced stage esophageal cancer complicated by esophageal stricture and esophagus-bronchial fistula. Methods: Self-expanded covered stents were placed into 48 patients with advanced stage esophageal cancer under fluoroscopy. Of the 48 patients, 39 had malignant esophageal stricture and 9 had esophagus-bronchus fistula. Results: Stents were successfully inserted into all but one patient with lower esophageal cancer and gastric volvulus. Deglutition was improved in all patients and coughing resolved in patients with esophagus-bronchus fistula. Thoracodynia and foreign body sensation vanished within one week after operation in all patients. Dyspnea caused by compression of the left main bronchus occurred in one patient. Re-stenosis of the stents occurred three to seven months after operation in eight patients. The mean survival time was seven months in all patients. Conclusion: Self-expanded covered stent placement is a simple, safe and reliable treatment method for advanced stage esophageal cancer and can effectively lengthen survival time. (authors)

Gross and net land cover changes in the main plant functional types derived from the annual ESA CCI land cover maps (1992-2015)

Science.gov (United States)

Li, Wei; MacBean, Natasha; Ciais, Philippe; Defourny, Pierre; Lamarche, Céline; Bontemps, Sophie; Houghton, Richard A.; Peng, Shushi

2018-01-01

Land-use and land-cover change (LULCC) impacts local energy and water balance and contributes on global scale to a net carbon emission to the atmosphere. The newly released annual ESA CCI (climate change initiative) land cover maps provide continuous land cover changes at 300 m resolution from 1992 to 2015, and can be used in land surface models (LSMs) to simulate LULCC effects on carbon stocks and on surface energy budgets. Here we investigate the absolute areas and gross and net changes in different plant functional types (PFTs) derived from ESA CCI products. The results are compared with other datasets. Global areas of forest, cropland and grassland PFTs from ESA are 30.4, 19.3 and 35.7 million km2 in the year 2000. The global forest area is lower than that from LUH2v2h (Hurtt et al., 2011), Hansen et al. (2013) or Houghton and Nassikas (2017) while cropland area is higher than LUH2v2h (Hurtt et al., 2011), in which cropland area is from HYDE 3.2 (Klein Goldewijk et al., 2016). Gross forest loss and gain during 1992-2015 are 1.5 and 0.9 million km2 respectively, resulting in a net forest loss of 0.6 million km2, mainly occurring in South and Central America. The magnitudes of gross changes in forest, cropland and grassland PFTs in the ESA CCI are smaller than those in other datasets. The magnitude of global net cropland gain for the whole period is consistent with HYDE 3.2 (Klein Goldewijk et al., 2016), but most of the increases happened before 2004 in ESA and after 2007 in HYDE 3.2. Brazil, Bolivia and Indonesia are the countries with the largest net forest loss from 1992 to 2015, and the decreased areas are generally consistent with those from Hansen et al. (2013) based on Landsat 30 m resolution images. Despite discrepancies compared to other datasets, and uncertainties in converting into PFTs, the new ESA CCI products provide the first detailed long-term time series of land-cover change and can be implemented in LSMs to characterize recent carbon dynamics

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

Science.gov (United States)

Yeo, I.-Y.; Lee, S.; Sadeghi, A. M.; Beeson, P. C.; Hively, W. D.; McCarty, G. W.; Lang, M. W.

2014-12-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay watershed (CBW), which is located in the mid-Atlantic US, winter cover crop use has been emphasized, and federal and state cost-share programs are available to farmers to subsidize the cost of cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops to improve water quality at the watershed scale (~ 50 km2) and to identify critical source areas of high nitrate export. A physically based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data to simulate hydrological processes and agricultural nutrient cycling over the period of 1990-2000. To accurately simulate winter cover crop biomass in relation to growing conditions, a new approach was developed to further calibrate plant growth parameters that control the leaf area development curve using multitemporal satellite-based measurements of species-specific winter cover crop performance. Multiple SWAT scenarios were developed to obtain baseline information on nitrate loading without winter cover crops and to investigate how nitrate loading could change under different winter cover crop planting scenarios, including different species, planting dates, and implementation areas. The simulation results indicate that winter cover crops have a negligible impact on the water budget but significantly reduce nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading from agricultural lands was approximately 14 kg ha-1, but decreased to 4.6-10.1 kg ha-1 with cover crops resulting in a reduction rate of 27-67% at the watershed scale. Rye was the most effective species, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of cover crops (~ 30

Monitoring land use/land cover changes using CORINE land cover data: a case study of Silivri coastal zone in Metropolitan Istanbul.

Science.gov (United States)

Yilmaz, Rüya

2010-06-01

The objective of the present study was to assess changes in land use/land cover patterns in the coastal town of Silivri, a part of greater Istanbul administratively. In the assessment, remotely sensed data, in the form of satellite images, and geographic information systems were used. Types of land use/land cover were designated as the percentage of the total area studied. Results calculated from the satellite data for land cover classification were compared successfully with the database Coordination of Information on the Environment (CORINE). This served as a reference to appraise the reliability of the study presented here. The CORINE Program was established by the European Commission to create a harmonized Geographical Information System on the state of the environment in the European Community. Unplanned urbanization is causing land use changes mainly in developing countries such as Turkey. This situation in Turkey is frequently observed in the city of Istanbul. There are only a few studies of land use-land cover changes which provide an integrated assessment of the biophysical and societal causes and consequences of environmental degradation in Istanbul. The research area comprised greater Silivri Town which is situated by the coast of Marmara Sea, and it is located approximately 60 km west of Istanbul. The city of Istanbul is one of the largest metropolises in Europe with ca. 15 million inhabitants. Additionally, greater Silivri is located near the terminal point of the state highway connecting Istanbul with Europe. Measuring of changes occurring in land use would help control future planning of settlements; hence, it is of importance for the Greater Silivri and Silivri Town. Following our evaluations, coastal zone of Silivri was classified into the land use groups of artificial surfaces agricultural areas and forests and seminatural areas with 47.1%, 12.66%, and 22.62%, respectively.

Revegetation/rock cover for stabilization of inactive U-tailings sites

International Nuclear Information System (INIS)

Beedlow, P.A.; Cadwell, L.L.

1982-01-01

Soil placed over any sealant/barrier system can provide a protective mantle if the soil is not lost by erosion. Vegetation is an attractive choice for controlling erosion because it can provide an economic self-renewing cover that serves to reduce erosion by both wind and water. Vegetation alone, however, may not adequately stabilize the surface in extremely arid areas. In those areas, a properly designed surface treatment of rock cover, perhaps in conjunction with vegetation, may be necessary to stabilize the tailings surfaces. The objective of this program is to establish guidelines for surface stabilization that are compatible with sealant/barrier systems and that are suited to soils and climates at inactive uranium mill tailings sites. These guidelines will provide the means to estimate potential vegetation cover, potential erosion, effects of surface treatments on sealant/barrier systems, and costs of vegetation and rock covers. Methods for establishing vegetation on sealed tailings will also be provided

Migration and Enrichment of Arsenic in the Rock-Soil-Crop Plant System in Areas Covered with Black Shale, Korea

Directory of Open Access Journals (Sweden)

Ji-Min Yi

2003-01-01

Full Text Available The Okchon black shale, which is part of the Guryongsan Formation or the Changri Formation of Cambro-Ordovician age in Korea provides a typical example of natural geological materials enriched with potentially toxic elements such as U, V, Mo, As, Se, Cd, and Zn. In this study, the Dukpyung and the Chubu areas were selected to investigate the migration and enrichment of As and other toxic elements in soils and crop plants in areas covered with black shale. Rock and soil samples digested in 4-acid solution (HCl+HNO3+HF+HClO4 were analyzed for As and other heavy metals by ICP-AES and ICP-MS, and plant samples by INAA. Mean concentration of As in Okchon black shale is higher than those of both world average values of shale and black shale. Especially high concentration of 23.2 mg As kg-1 is found in black shale from the Dukpyung area. Mean concentration of As is highly elevated in agricultural soils from the Dukpyung (28.2 mg kg-1 and the Chubu areas (32.6 mg kg-1. As is highly elevated in rice leaves from the Dukpyung (1.14 mg kg-1 and the Chubu areas (1.35 mg kg-1. The biological absorption coefficient (BAC of As in plant species decreases in the order of rice leaves > corn leaves > red pepper = soybean leaves = sesame leaves > corn stalks > corn grains. This indicates that leafy plants tend to accumulate As from soil to a greater degree than cereal products such as grains.

GENERATION OF 2D LAND COVER MAPS FOR URBAN AREAS USING DECISION TREE CLASSIFICATION

DEFF Research Database (Denmark)

Höhle, Joachim

2014-01-01

A 2D land cover map can automatically and efficiently be generated from high-resolution multispectral aerial images. First, a digital surface model is produced and each cell of the elevation model is then supplemented with attributes. A decision tree classification is applied to extract map objects...... of stereo-observations of false-colour stereopairs. The stratified statistical assessment of the produced land cover map with six classes and based on 91 points per class reveals a high thematic accuracy for classes ‘building’ (99%, 95% CI: 95%-100%) and ‘road and parking lot’ (90%, 95% CI: 83%-95%). Some...

Identification of land cover changes in the coastal area of Dakshina Kannada district, South India during the year 2004–2008

Directory of Open Access Journals (Sweden)

J. Jayanth

2016-06-01

Full Text Available This study investigates land cover (LC changes in the coastal area of Dakshina Kannada district in the state of Karnataka, South India, during the years 2004–2008 as a case study. IRS P-6, Linear Imaging Self Scanning sensor (LISS-IV satellite images were used in the present work. Classification was carried out using artificial bee colony algorithm and support vector machine (SVM which gave a better result compared to other traditional classification techniques. The best overall classification accuracy for the study area was achieved with an ABC classifier with an OCA of 80.35% for 2004 year data and OCA of 80.40% for 2008 year data, whereas the OCA in SVM, for the same training set is 71.42% for 2004 data and 71.38% for 2008 data on study area 1 and the results were optimised with respect to multispectral data. In study area 2, ABC algorithm achieved an OCA of 78.17% and MLC of 62.63% which was used to check the universality of the classifier. The classification results with post-classification technique for study area 1 indicate that urbanisation in the study area has almost increased twice. During the same time there is an increase in the forest plantation, agricultural plantation and a decrease in crop land and land without scrubs, indicates rapid changes in the coastal environment.

Combining MOD10A1 and MYD10A1 Images For Snow Cover Area Monitoring

Science.gov (United States)

Tekeli, A. E.

2008-12-01

MOD10A1 and MYD10A1 daily snow cover maps at 500 m resolution are available from MODIS sensors on Terra and Aqua satellites. Aqua obtains the image of same region approximately three hours after Terra over Turkey region. MODIS is an optic sensor and cloud cover degrades the usability of derived snow cover maps. Moreover, spectral similarity between clouds and snow complicates their separability in visible imagery. Fortunately, dynamic behavior of clouds enables their discrimination from snow stationary on the surface. Combined use of MOD10A1 and MYD10A1 images mostly reduces the cloud cover present in one image alone and provides better representation of surface snow cover. Comparison of merged images with in situ data indicated higher hit ratios. The individual comparison of MOD10A1 and MYD10A1 images with ground data each yielded 31% hit ratio whereas, the merged images provided 38%. One-day shifts in comparisons increased hit ratios to 52 % and 46% whereas and two-day shifts gave 77 % and 79 % for MOD10A1 and MYD10A1 respectively. Merged maps yielded 54% and 83% for one and two day shifts. The improvement provided by the merging technique is found to be 7% for the present day, 7 % for one- day and 5% for two-day shifts for the whole season. Monthly decomposition resulted 25% improvement as the maximum. The snow cover product obtained by merging Terra and Aqua satellites provided higher hit ratios, as expected.

Open land cover from OpenStreetMap and remote sensing

Science.gov (United States)

Schultz, Michael; Voss, Janek; Auer, Michael; Carter, Sarah; Zipf, Alexander

2017-12-01

OpenStreetMap (OSM) tags were used to produce a global Open Land Cover (OLC) product with fractional data gaps available at osmlanduse.org. Data gaps in the global OLC map were filled for a case study in Heidelberg, Germany using free remote sensing data, which resulted in a land cover (LC) prototype with complete coverage in this area. Sixty tags in the OSM were used to allocate a Corine Land Cover (CLC) level 2 land use classification to 91.8% of the study area, and the remaining gaps were filled with remote sensing data. For this case study, complete are coverage OLC overall accuracy was estimated 87%, which performed better than the CLC product (81% overall accuracy) of 2012. Spatial thematic overlap for the two products was 84%. OLC was in large parts found to be more detailed than CLC, particularly when LC patterns were heterogeneous, and outperformed CLC in the classification of 12 of the 14 classes. Our OLC product represented data created in different periods; 53% of the area was 2011-2016, and 46% of the area was representative of 2016-2017.

Responses of Vegetation Cover to Environmental Change in Large Cities of China

Directory of Open Access Journals (Sweden)

Kai Jin

2018-01-01

Full Text Available Vegetation cover is crucial for the sustainability of urban ecosystems; however, this cover has been undergoing substantial changes in cities. Based on climate data, city statistical data, nighttime light data and the Normalized Difference Vegetation Index (NDVI dataset, we investigate the spatiotemporal variations of climate factors, urban lands and vegetation cover in 71 large cities of China during 1998–2012, and explore their correlations. A regression model between growing-season NDVI (G-NDVI and urban land proportion (PU is built to quantify the impact of urbanization on vegetation cover change. The results indicate that the spatiotemporal variations of temperature, precipitation, PU and G-NDVI are greatly different among the 71 cities which experienced rapid urbanization. The spatial difference of G-NDVI is closely related to diverse climate conditions, while the inter-annual variations of G-NDVI are less sensitive to climate changes. In addition, there is a negative correlation between G-NDVI trend and PU change, indicating vegetation cover in cities have been negatively impacted by urbanization. For most of the inland cities, the urbanization impacts on vegetation cover in urban areas are more severe than in suburban areas. But the opposite occurs in 17 cities mainly located in the coastal areas which have been undergoing the most rapid urbanization. Overall, the impacts of urbanization on G-NDVI change are estimated to be −0.026 per decade in urban areas and −0.015 per decade in suburban areas during 1998–2012. The long-term developments of cities would persist and continue to impact on the environmental change and sustainability. We use a 15-year window here as a case study, which implies the millennia of human effects on the natural biotas and warns us to manage landscapes and preserve ecological environments properly.

Effect of land cover change on runoff curve number estimation in Iowa, 1832-2001

Science.gov (United States)

Wehmeyer, Loren L.; Weirich, Frank H.; Cuffney, Thomas F.

2011-01-01

Within the first few decades of European-descended settlers arriving in Iowa, much of the land cover across the state was transformed from prairie and forest to farmland, patches of forest, and urbanized areas. Land cover change over the subsequent 126 years was minor in comparison. Between 1832 and 1859, the General Land Office conducted a survey of the State of Iowa to aid in the disbursement of land. In 1875, an illustrated atlas of the State of Iowa was published, and in 2001, the US Geological Survey National Land Cover Dataset was compiled. Using these three data resources for classifying land cover, the hydrologic impact of the land cover change at three points in time over a period of 132+ years is presented in terms of the effect on the area-weighted average curve number, a term commonly used to predict peak runoff from rainstorms. In the four watersheds studied, the area-weighted average curve number associated with the first 30 years of settlement increased from 61·4 to 77·8. State-wide mapped forest area over this same period decreased 19%. Over the next 126 years, the area-weighted average curve number decreased to 76·7, despite an additional forest area reduction of 60%. This suggests that degradation of aquatic resources (plants, fish, invertebrates, and habitat) arising from hydrologic alteration was likely to have been much higher during the 30 years of initial settlement than in the subsequent period of 126 years in which land cover changes resulted primarily from deforestation and urbanization. 

A Study of the Role of Clouds in the Relationship Between Land Use/Land Cover and the Climate and Air Quality of the Atlanta Area

Science.gov (United States)

Kidder, Stanley Q.; Hafner, Jan

2001-01-01

The goal of Project ATLANTA is to derive a better scientific understanding of how land cover changes associated with urbanization affect climate and air quality. In this project the role that clouds play in this relationship was studied. Through GOES satellite observations and RAMS modeling of the Atlanta area, we found that in Atlanta (1) clouds are more frequent than in the surrounding rural areas; (2) clouds cool the surface by shading and thus tend to counteract the warming effect of urbanization; (3) clouds reflect sunlight, which might other wise be used to produce ozone; and (4) clouds decrease biogenic emission of ozone precursors, and they probably decrease ozone concentration. We also found that mesoscale modeling of clouds, especially of small, summertime clouds, needs to be improved and that coupled mesoscale and air quality models are needed to completely understand the mediating role that clouds play in the relationship between land use/land cover change and the climate and air quality of Atlanta. It is strongly recommended that more cities be studied to strengthen and extend these results.

Seasonal snow cover regime and historical change in Central Asia from 1986 to 2008

Science.gov (United States)

Zhou, Hang; Aizen, Elena; Aizen, Vladimir

2017-01-01

A series of statistics describing seasonal Snow Cover Extent and timing in Central Asia (CA) have been derived from AVHRR satellite images for the time period from 1986 to 2008. Analysis of long term mean snow cover statistics shows that the area weighted mean of long term Snow Covering Days (SCD) for the whole CA is 95.2 ± 65.7 days. High elevation mountainous areas above 3000 m in Altai, Tien Shan and Pamir, which account for about 2.8% of total area in CA, have SCD > 240 days. Deserts (Karakorum Desert, Taklamakan Desert, Kumtag Desert) and rain shadow areas of major mountains, accounting for 27.0% of total area in CA, have SCD in the range of 0-30 days. Factors affecting snow cover distribution have been analyzed using simple linear regression and segmented regression. For plain regions and windward regions, the SCD rate is + 5.9 days/100 m, while for leeward regions, the rate jumps from + 0.7 days/100 m to + 10.0 days/100 m at about 2335 m. Latitude affects the SCD, especially in plain regions with insignificant change of elevation, with rates of 9-10 days/degree from south to north. The Mann-Kendal test and the Theil-Sen regression methods have been applied to analyze the spatial heterogeneous trends of change of SCD, Snow Cover Onset Date (SCOD), and Snow Cover Melt Date (SCMD). Area weighed mean SCD in the whole CA does not exhibit significant trend of change from 1986 to 2008. Increase of SCD was observed in the northeastern Kazakh Steppe. Low elevation areas below 2000 m in Central Tien Shan and Eastern Tien Shan, as well as mid-elevation areas from 1000 m to 3000 m in Western Tien Shan, Pamiro-Alai and Western Pamir, also experienced increase of SCD, associated with both earlier SCOD and later SCMD. Decrease of SCD was observed in mountainous areas of Altai, Tien Shan and Pamir, and vast areas in plains surrounding the Aral Sea.

Snow Cover Monitoring Using MODIS Data in Liaoning Province, Northeastern China

Directory of Open Access Journals (Sweden)

Yu Lu

2010-03-01

Full Text Available This paper presents the results of snow cover monitoring studies in Liaoning Province, northeastern China, using MODIS data. Snow cover plays an important role in both the regional water balance and soil moisture properties during the early spring in northeastern China. In addition, heavy snowfalls commonly trigger hazards such as flooding, caused by rapid snow melt, or crop failure, resulting from fluctuations in soil temperature associated with changes in the snow cover. The latter is a function of both regional, or global, climatic changes, as well as fluctuations in the albedo resulting from variations in the Snow Covered Area (SCA. These impacts are crucial to human activities, especially to those living in middle-latitude areas such as Liaoning Province. Thus, SCA monitoring is currently an important tool in studies of global climate change, particularly because satellite remote sensing data provide timely and efficient snow cover information for large areas. In this study, MODIS L1B data, MODIS Daily Snow Products (MOD10A1 and MODIS 8-day Snow Products (MOD10A2 were used to monitor the SCA of Liaoning Province over the winter months of November–April, 2006–2008. The effects of cloud masking and forest masking on the snow monitoring results were also assessed. The results show that the SCA percentage derived from MODIS L1B data is relatively consistent, but slightly higher than that obtained from MODIS Snow Products. In situ data from 25 snow stations were used to assess the accuracy of snow cover monitoring from the SCA compared to the results from MODIS Snow Products. The studies found that the SCA results were more reliable than MODIS Snow Products in the study area.

Spatial and temporal land cover changes in Terminos Lagoon Reserve, Mexico.

Science.gov (United States)

Soto-Galera, Ernesto; Piera, Jaume; López, Pilar

2010-06-01

Terminos Lagoon ecosystem is the largest fluvial-lagoon estuarine system in the country and one of the most important reserves of coastal flora and fauna in Mexico. Since the seventies, part of the main infrastructure for country's oil extraction is located in this area. Its high biodiversity has motivated different type of studies including deforestation processes and land use planning. In this work we used satellite image analysis to determine land cover changes in the area from 1974 to 2001. Our results indicate that tropical forest and mangroves presented the most extensive losses in its coverage. In contrast, urban areas and induced grassland increased considerably. In 2001 more than half of the ecosystem area showed changes from its original land cover, and a third part of it was deteriorated. The main causes of deforestation were both the increase in grassland and the growth of urban areas. However, deforestation was attenuated by natural reforestation and plant canopy recovery. We conclude that the introduction of cattle and urban development were the main causes for the land cover changes; however, the oil industry activity located in the ecosystem, has promoted indirectly to urban growth and rancher boom.

A simple semi-automatic approach for land cover classification from multispectral remote sensing imagery.

Directory of Open Access Journals (Sweden)

Dong Jiang

Full Text Available Land cover data represent a fundamental data source for various types of scientific research. The classification of land cover based on satellite data is a challenging task, and an efficient classification method is needed. In this study, an automatic scheme is proposed for the classification of land use using multispectral remote sensing images based on change detection and a semi-supervised classifier. The satellite image can be automatically classified using only the prior land cover map and existing images; therefore human involvement is reduced to a minimum, ensuring the operability of the method. The method was tested in the Qingpu District of Shanghai, China. Using Environment Satellite 1(HJ-1 images of 2009 with 30 m spatial resolution, the areas were classified into five main types of land cover based on previous land cover data and spectral features. The results agreed on validation of land cover maps well with a Kappa value of 0.79 and statistical area biases in proportion less than 6%. This study proposed a simple semi-automatic approach for land cover classification by using prior maps with satisfied accuracy, which integrated the accuracy of visual interpretation and performance of automatic classification methods. The method can be used for land cover mapping in areas lacking ground reference information or identifying rapid variation of land cover regions (such as rapid urbanization with convenience.

Tree Cover Mapping Tool—Documentation and user manual

Science.gov (United States)

Cotillon, Suzanne E.; Mathis, Melissa L.

2016-06-02

The Tree Cover Mapping (TCM) tool was developed by scientists at the U.S. Geological Survey Earth Resources Observation and Science Center to allow a user to quickly map tree cover density over large areas using visual interpretation of high resolution imagery within a geographic information system interface. The TCM tool uses a systematic sample grid to produce maps of tree cover. The TCM tool allows the user to define sampling parameters to estimate tree cover within each sample unit. This mapping method generated the first on-farm tree cover maps of vast regions of Niger and Burkina Faso. The approach contributes to implementing integrated landscape management to scale up re-greening and restore degraded land in the drylands of Africa. The TCM tool is easy to operate, practical, and can be adapted to many other applications such as crop mapping, settlements mapping, or other features. This user manual provides step-by-step instructions for installing and using the tool, and creating tree cover maps. Familiarity with ArcMap tools and concepts is helpful for using the tool.

Polyurethane-Covered Self-expandable Nitinol Stent for Malignant Biliary Obstruction: Preliminary Results

International Nuclear Information System (INIS)

Han, Young-Min; Hwang, Seung-Bae; Lee, Soo-Teik; Lee, Jeong-Min; Chung, Gyung-Ho

2002-01-01

Purpose: To evaluate the immediate and long-term results in ten patients with malignant biliary obstruction using a polyurethane-covered, self-expandable nitinol stent.Methods: A nitinol stent, fully covered with high-elasticity polyurethane, with an unconstrained diameter of 10 mm and a total length of 60-80 mm, was placed transhepatically under fluoroscopic guidance in ten patients. The length of the biliary obstruction varied between 30-50 mm. The follow-up examination included a clinical assessment, serum bilirubin measurement, and ultrasound examinations at one-month intervals in all patients. Results: Initial stent deployment was successful in eight patients. Two patients experienced proximal migration,which was solved by insertion of two, uncovered Wallstents. One patient had the stent removed after two weeks because of severe nausea and vomiting. One patient had delayed migration of the covered stent after 40 weeks. The follow-up duration was 3-40 weeks (Mean: 16.9 weeks). Seven patients died(3-26 weeks) and three patients survived (24-40 weeks). The bilirubin measurements in all patients had significantly decreased one week after stent insertion. The levels of amylase and lipase had did not increase after stent insertion. Conclusions: Apolyurethane-covered, self-expandable nitinol stent can be used effectively and safely in the treatment of malignant biliary obstruction. The preliminary results are favorable, but there is a need for further large studies to determine both long-term survival and patency

Area-averaged evapotranspiration over a heterogeneous land surface: aggregation of multi-point EC flux measurements with a high-resolution land-cover map and footprint analysis

Directory of Open Access Journals (Sweden)

F. Xu

2017-08-01

Full Text Available The determination of area-averaged evapotranspiration (ET at the satellite pixel scale/model grid scale over a heterogeneous land surface plays a significant role in developing and improving the parameterization schemes of the remote sensing based ET estimation models and general hydro-meteorological models. The Heihe Watershed Allied Telemetry Experimental Research (HiWATER flux matrix provided a unique opportunity to build an aggregation scheme for area-averaged fluxes. On the basis of the HiWATER flux matrix dataset and high-resolution land-cover map, this study focused on estimating the area-averaged ET over a heterogeneous landscape with footprint analysis and multivariate regression. The procedure is as follows. Firstly, quality control and uncertainty estimation for the data of the flux matrix, including 17 eddy-covariance (EC sites and four groups of large-aperture scintillometers (LASs, were carefully done. Secondly, the representativeness of each EC site was quantitatively evaluated; footprint analysis was also performed for each LAS path. Thirdly, based on the high-resolution land-cover map derived from aircraft remote sensing, a flux aggregation method was established combining footprint analysis and multiple-linear regression. Then, the area-averaged sensible heat fluxes obtained from the EC flux matrix were validated by the LAS measurements. Finally, the area-averaged ET of the kernel experimental area of HiWATER was estimated. Compared with the formerly used and rather simple approaches, such as the arithmetic average and area-weighted methods, the present scheme is not only with a much better database, but also has a solid grounding in physics and mathematics in the integration of area-averaged fluxes over a heterogeneous surface. Results from this study, both instantaneous and daily ET at the satellite pixel scale, can be used for the validation of relevant remote sensing models and land surface process models. Furthermore, this

Area-averaged evapotranspiration over a heterogeneous land surface: aggregation of multi-point EC flux measurements with a high-resolution land-cover map and footprint analysis

Science.gov (United States)

Xu, Feinan; Wang, Weizhen; Wang, Jiemin; Xu, Ziwei; Qi, Yuan; Wu, Yueru

2017-08-01

The determination of area-averaged evapotranspiration (ET) at the satellite pixel scale/model grid scale over a heterogeneous land surface plays a significant role in developing and improving the parameterization schemes of the remote sensing based ET estimation models and general hydro-meteorological models. The Heihe Watershed Allied Telemetry Experimental Research (HiWATER) flux matrix provided a unique opportunity to build an aggregation scheme for area-averaged fluxes. On the basis of the HiWATER flux matrix dataset and high-resolution land-cover map, this study focused on estimating the area-averaged ET over a heterogeneous landscape with footprint analysis and multivariate regression. The procedure is as follows. Firstly, quality control and uncertainty estimation for the data of the flux matrix, including 17 eddy-covariance (EC) sites and four groups of large-aperture scintillometers (LASs), were carefully done. Secondly, the representativeness of each EC site was quantitatively evaluated; footprint analysis was also performed for each LAS path. Thirdly, based on the high-resolution land-cover map derived from aircraft remote sensing, a flux aggregation method was established combining footprint analysis and multiple-linear regression. Then, the area-averaged sensible heat fluxes obtained from the EC flux matrix were validated by the LAS measurements. Finally, the area-averaged ET of the kernel experimental area of HiWATER was estimated. Compared with the formerly used and rather simple approaches, such as the arithmetic average and area-weighted methods, the present scheme is not only with a much better database, but also has a solid grounding in physics and mathematics in the integration of area-averaged fluxes over a heterogeneous surface. Results from this study, both instantaneous and daily ET at the satellite pixel scale, can be used for the validation of relevant remote sensing models and land surface process models. Furthermore, this work will be

The potential of remote sensing for monitoring land cover changes and effects on physical geography in the area of Kayisdagi Mountain and its surroundings (Istanbul).

Science.gov (United States)

Geymen, Abdurrahman; Baz, Ibrahim

2008-05-01

The effect of land cover change, from natural to anthropogenic, on physical geography conditions has been studied in Kayisdagi Mountain. Land degradation is the most important environmental issue involved in this study. Most forms of land degradation are natural processes accelerated by human activity. Land degradation is a human induced or natural process that negatively affects the ability of land to function effectively within an ecosystem. Environmental degradation from human pressure and land use has become a major problem in the study area because of high population growth, urbanization rate, and the associated rapid depletion of natural resources. When studying the cost of land degradation, it is not possible to ignore the role of urbanization. In particular, a major cause of deforestation is conversion to urban land. The paper reviews the principles of current remote sensing techniques considered particularly suitable for monitoring Kayisdagi Mountain and its surrounding land cover changes and their effects on physical geography conditions. In addition, this paper addresses the problem of how spatially explicit information about degradation processes in the study area rangelands can be derived from different time series of satellite data. The monitoring approach comprises the time period between 1990 and 2005. Satellite remote sensing techniques have proven to be cost effective in widespread land cover changes. Physical geography and particularly natural geomorphologic processes like erosion, mass movement, physical weathering, and chemical weathering features etc. have faced significant unnatural variation.

Forest Cover Change Analysis in Inner Mongolia Using Remote Sensing Data

Science.gov (United States)

Xie, S.; Gong, J.; Huang, X.

2018-04-01

Forest is the lung of the earth, and it has important effect on maintaining the ecological balance of the whole earth. This study was conducted in Inner Mongolia during the year 1990-2015. Land use and land cover data were used to obtain forest cover change of Inner Mongolia. In addition, protected area data, road data, ASTER GDEM data were combined with forest cover change data to analyze the relationship between them. Moreover, patch density and landscape shape index were calculated to analyze forest change in perspective of landscape aspect. The results indicated that forest area increased overall during the study period. However, a few cities still had a phenomenon of reduced forest area. Results also demonstrated that the construction of protected area had positive effect on protecting forest while roads may disturbed forest due to human activities. In addition, forest patches in most of cities of Inner Mongolia tended to be larger and less fragmented. This paper reflected forest change in Inner Mongolia objectively, which is helpful for policy making by government.

Guidelines for selection of radiological protective head covering

International Nuclear Information System (INIS)

Galloway, G.R. Jr.

1995-08-01

The hood is recognized throughout the nuclear industry as the standard radiological protective head covering for use in radioactively contaminated work environments. As of June 15, 1995, hoods were required for all activities performed in contaminated areas at the Y-12 Plant. The use of hoods had historically been limited to those radiological activities with a high potential for personnel contamination. Due to the large size of many posted contaminated areas at the Y-12 Plant, and compounding safety factors, requirements for the use of hoods are being reevaluated. The purpose of the evaluation is to develop technically sound guidelines for the selection of hoods when prescribing radiological protective head covering. This report presents the guidelines for selection of radiological protective hoods

Forecasting summertime surface temperature and precipitation in the Mexico City metropolitan area: sensitivity of the WRF model to land cover changes

Science.gov (United States)

López-Bravo, Clemente; Caetano, Ernesto; Magaña, Víctor

2018-02-01

Changes in the frequency and intensity of severe hydrometeorological events in recent decades in the Mexico City Metropolitan Area have motivated the development of weather warning systems. The weather forecasting system for this region was evaluated in sensitivity studies using the Weather Research and Forecasting Model (WRF) for July 2014, a summer time month. It was found that changes in the extent of the urban area and associated changes in thermodynamic and dynamic variables have induced local circulations that affect the diurnal cycles of temperature, precipitation, and wind fields. A newly implemented configuration (land cover update and Four-Dimensional Data Assimilation (FDDA)) of the WRF model has improved the adjustment of the precipitation field to the orography. However, errors related to the depiction of convection due to parameterizations and microphysics remains a source of uncertainty in weather forecasting in this region.

Changes in Andes snow cover from MODIS data, 2000-2016

Science.gov (United States)

Saavedra, Freddy A.; Kampf, Stephanie K.; Fassnacht, Steven R.; Sibold, Jason S.

2018-03-01

The Andes span a length of 7000 km and are important for sustaining regional water supplies. Snow variability across this region has not been studied in detail due to sparse and unevenly distributed instrumental climate data. We calculated snow persistence (SP) as the fraction of time with snow cover for each year between 2000 and 2016 from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensors (500 m, 8-day maximum snow cover extent). This analysis is conducted between 8 and 36° S due to high frequency of cloud (> 30 % of the time) south and north of this range. We ran Mann-Kendall and Theil-Sens analyses to identify areas with significant changes in SP and snowline (the line at lower elevation where SP = 20 %). We evaluated how these trends relate to temperature and precipitation from Modern-Era Retrospective Analysis for Research and Applications-2 (MERRA2) and University of Delaware datasets and climate indices as El Niño-Southern Oscillation (ENSO), Southern Annular Mode (SAM), and Pacific Decadal Oscillation (PDO). Areas north of 29° S have limited snow cover, and few trends in snow persistence were detected. A large area (34 370 km2) with persistent snow cover between 29 and 36° S experienced a significant loss of snow cover (2-5 fewer days of snow year-1). Snow loss was more pronounced (62 % of the area with significant trends) on the east side of the Andes. We also found a significant increase in the elevation of the snowline at 10-30 m year-1 south of 29-30° S. Decreasing SP correlates with decreasing precipitation and increasing temperature, and the magnitudes of these correlations vary with latitude and elevation. ENSO climate indices better predicted SP conditions north of 31° S, whereas the SAM better predicted SP south of 31° S.

Influence of winter sea-ice motion on summer ice cover in the Arctic

Directory of Open Access Journals (Sweden)

Noriaki Kimura

2013-11-01

Full Text Available Summer sea-ice cover in the Arctic varies largely from year to year owing to several factors. This study examines one such factor, the relationship between interannual difference in winter ice motion and ice area in the following summer. A daily-ice velocity product on a 37.5-km resolution grid is prepared using the satellite passive microwave sensor Advanced Microwave Scanning Radiometer—Earth Observing System data for the nine years of 2003–2011. Derived daily-ice motion reveals the dynamic modification of the winter ice cover. The winter ice divergence/convergence is strongly related to the summer ice cover in some regions; the correlation coefficient between the winter ice convergence and summer ice area ranges between 0.5 and 0.9 in areas with high interannual variability. This relation implies that the winter ice redistribution controls the spring ice thickness and the summer ice cover.

Ground penetrating radar utilization in exploring inadequate concrete covers in a new bridge deck

Directory of Open Access Journals (Sweden)

Md. Istiaque Hasan

2014-01-01

Full Text Available The reinforced concrete cast in place four span deck of a concrete bridge near Roanoke, Texas, was recently completed. Due to possible construction errors, it was suspected that the concrete covers in the deck did not conform to drawings and specifications. A full scale non-destructive evaluation of the concrete covers was carried out using ground penetrating radar (GPR equipment. Cover values were determined from the radargram generated from the scan. The estimated covers were plotted on contour maps. Migration data can substitute the drilling based ground truth data without compromising the concrete cover estimations, except for areas with very high cover values. Areas with high water content may result in inaccurate concrete dielectric constants. Based on the results, significant retrofitting of the bridge deck, such as additional overlay, was recommended.

Dissociated Crossed Speech Areas in a Tumour Patient

Directory of Open Access Journals (Sweden)

Jörg Mauler

2017-05-01

Full Text Available In the past, the eloquent areas could be deliberately localised by the invasive Wada test. The very rare cases of dissociated crossed speech areas were accidentally found based on the clinical symptomatology. Today functional magnetic resonance imaging (fMRI-based imaging can be employed to non-invasively localise the eloquent areas in brain tumour patients for therapy planning. A 41-year-old, left-handed man with a low-grade glioma in the left frontal operculum extending to the insular cortex, tension headaches, and anomic aphasia over 5 months underwent a pre-operative speech area localisation fMRI measurement, which revealed the evidence of the transhemispheric disposition, where the dominant Wernicke speech area is located on the left and the Broca’s area is strongly lateralised to the right hemisphere. The outcome of the Wada test and the intraoperative cortico-subcortical stimulation mapping were congruent with this finding. After tumour removal, language area function was fully preserved. Upon the occurrence of brain tumours with a risk of impaired speech function, the rare dissociate crossed speech areas disposition may gain a clinically relevant meaning by allowing for more extended tumour removal. Hence, for its identification, diagnostics which take into account both brain hemispheres, such as fMRI, are recommended.

Ten Years of Forest Cover Change in the Sierra Nevada Detected Using Landsat Satellite Image Analysis

Science.gov (United States)

Potter, Christopher S.

2014-01-01

The Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) methodology was applied to detected changes in forest vegetation cover for areas burned by wildfires in the Sierra Nevada Mountains of California between the periods of 1975- 79 and 1995-1999. Results for areas burned by wildfire between 1995 and 1999 confirmed the importance of regrowing forest vegetation over 17% of the combined burned areas. A notable fraction (12%) of the entire 5-km (unburned) buffer area outside the 1995-199 fires perimeters showed decline in forest cover, and not nearly as many regrowing forest areas, covering only 3% of all the 1995-1999 buffer areas combined. Areas burned by wildfire between 1975 and 1979 confirmed the importance of disturbed (or declining evergreen) vegetation covering 13% of the combined 1975- 1979 burned areas. Based on comparison of these results to ground-based survey data, the LEDAPS methodology should be capable of fulfilling much of the need for consistent, low-cost monitoring of changes due to climate and biological factors in western forest regrowth following stand-replacing disturbances.

Guide for In-Place Treatment of Covered and Timber Bridges

Science.gov (United States)

Stan Lebow; Grant Kirker; Robert White; Terry Amburgey; H. Michael Barnes; Michael Sanders; Jeff Morrell

2012-01-01

Historic covered bridges and current timber bridges can be vulnerable to damage from biodeterioration or fire. This guide describes procedures for selecting and applying in-place treatments to prevent or arrest these forms of degradation. Vulnerable areas for biodeterioration in covered bridges include members contacting abutments, members near the ends of bridges...

Development of a 30 m Spatial Resolution Land Cover of Canada: Contribution to the Harmonized North America Land Cover Dataset

Science.gov (United States)

Pouliot, D.; Latifovic, R.; Olthof, I.

2017-12-01

Land cover is needed for a large range of environmental applications regarding climate impacts and adaption, emergency response, wildlife habitat, air quality, water yield, etc. In Canada a 2008 user survey revealed that the most practical scale for provision of land cover data is 30 m, nationwide, with an update frequency of five years (Ball, 2008). In response to this need the Canada Centre for Remote Sensing has generated a 30 m land cover of Canada for the base year 2010 as part of a planned series of maps at the recommended five year update frequency. This land cover is the Canadian contribution to the North American Land Change Monitoring System initiative, which seeks to provide harmonized land cover across Canada, the United States, and Mexico. The methodology developed in this research utilized a combination of unsupervised and machine learning techniques to map land cover, blend results between mapping units, locally optimize results, and process some thematic attributes with specific features sets. Accuracy assessment with available field data shows it was on average 75% for the five study areas assessed. In this presentation an overview of the unique processing aspects, example results, and initial accuracy assessment will be discussed.

Effects of Forest Cover Change on Flood Characteristics in the Upper Citarum Watershed

Directory of Open Access Journals (Sweden)

Bambang Dwi Dasanto

2015-02-01

Full Text Available Information on the effect of forest cover changes on streamflow (river discharge in large-scale catchment is important to be studied. The rate of forest cover change in the Upper Citarum Watershed as a large-scale catchment is high enough to drive streamflow change, such as increase of discharge level, or flood volume. Within the research area, flood would occur when the volume of streamflow exceeded the canal capacity and inundated areas that were normally dry. Therefore, this research focused on identifying the effects of forest cover change on flood events and its distribution. The research consisted of 2 main stages; firstly, building geometric data of river and performing frequency analysis of historical and scenario discharges using an approach of probability distribution; and, secondly, flood inundation mapping using HEC-RAS model. The results showed that forest reduction have affected water yield in the downstream of Upper Citarum Watershed. In each return period, this reduction have increased river discharge level and affected the spread of flooded areas. In 2-year return period, the extent of flood as an impact of forest reduction was estimated to decrease slowly. However, in the return period of more than 2 years, the spread of flooded areas increased sharply. These proved that forest cover reduction would always increase the discharge value, but it did not always expand the inundated area.Keywords: geometric data, forest cover, water yield, return period

Scintigraphic investigation of clavicular bone area in patients with psoriasis

International Nuclear Information System (INIS)

Aso, Kazuo; Amano, Michiko; Sekiya, Sakae; Komatani, Akio

1984-01-01

Bone scintigraphy with sup(99m)Tc-methylene diphosphonate (MDP) was performed in 38 patients with psoriasis, 5 patients with palmoplantar pustulosis, and 56 control subjects. Abnormal uptake was seen primarily in the sternoclavicular junction and the cartilage of the first rib in 24 of the patients with psoriasis (63%) and in 3 of the patients with palmoplantar pustulosis (60%), and in the sternoclavicular junction in 21 of the control subjects (38%). The incidence of uptake in the sternoclavicular junction area in the psoriasis patients clearly exceeded that in the control subjects. (Namekawa, K.)

Exploring diversity in ensemble classification: Applications in large area land cover mapping

Science.gov (United States)

Mellor, Andrew; Boukir, Samia

2017-07-01

Ensemble classifiers, such as random forests, are now commonly applied in the field of remote sensing, and have been shown to perform better than single classifier systems, resulting in reduced generalisation error. Diversity across the members of ensemble classifiers is known to have a strong influence on classification performance - whereby classifier errors are uncorrelated and more uniformly distributed across ensemble members. The relationship between ensemble diversity and classification performance has not yet been fully explored in the fields of information science and machine learning and has never been examined in the field of remote sensing. This study is a novel exploration of ensemble diversity and its link to classification performance, applied to a multi-class canopy cover classification problem using random forests and multisource remote sensing and ancillary GIS data, across seven million hectares of diverse dry-sclerophyll dominated public forests in Victoria Australia. A particular emphasis is placed on analysing the relationship between ensemble diversity and ensemble margin - two key concepts in ensemble learning. The main novelty of our work is on boosting diversity by emphasizing the contribution of lower margin instances used in the learning process. Exploring the influence of tree pruning on diversity is also a new empirical analysis that contributes to a better understanding of ensemble performance. Results reveal insights into the trade-off between ensemble classification accuracy and diversity, and through the ensemble margin, demonstrate how inducing diversity by targeting lower margin training samples is a means of achieving better classifier performance for more difficult or rarer classes and reducing information redundancy in classification problems. Our findings inform strategies for collecting training data and designing and parameterising ensemble classifiers, such as random forests. This is particularly important in large area

Echocardiography underestimates stroke volume and aortic valve area: implications for patients with small-area low-gradient aortic stenosis.

Science.gov (United States)

Chin, Calvin W L; Khaw, Hwan J; Luo, Elton; Tan, Shuwei; White, Audrey C; Newby, David E; Dweck, Marc R

2014-09-01

Discordance between small aortic valve area (AVA; area (LVOTarea) and stroke volume alongside inconsistencies in recommended thresholds. One hundred thirty-three patients with mild to severe AS and 33 control individuals underwent comprehensive echocardiography and cardiovascular magnetic resonance imaging (MRI). Stroke volume and LVOTarea were calculated using echocardiography and MRI, and the effects on AVA estimation were assessed. The relationship between AVA and MPG measurements was then modelled with nonlinear regression and consistent thresholds for these parameters calculated. Finally the effect of these modified AVA measurements and novel thresholds on the number of patients with small-area low-gradient AS was investigated. Compared with MRI, echocardiography underestimated LVOTarea (n = 40; -0.7 cm(2); 95% confidence interval [CI], -2.6 to 1.3), stroke volumes (-6.5 mL/m(2); 95% CI, -28.9 to 16.0) and consequently, AVA (-0.23 cm(2); 95% CI, -1.01 to 0.59). Moreover, an AVA of 1.0 cm(2) corresponded to MPG of 24 mm Hg based on echocardiographic measurements and 37 mm Hg after correction with MRI-derived stroke volumes. Based on conventional measures, 56 patients had discordant small-area low-gradient AS. Using MRI-derived stroke volumes and the revised thresholds, a 48% reduction in discordance was observed (n = 29). Echocardiography underestimated LVOTarea, stroke volume, and therefore AVA, compared with MRI. The thresholds based on current guidelines were also inconsistent. In combination, these factors explain > 40% of patients with discordant small-area low-gradient AS. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

A study of low-density areas, clinical findings, and angiographic findings in patients with cerebral infarction

International Nuclear Information System (INIS)

Saiki, Iwao; Sakai, Yoshiaki; Oikawa, Tadato; Koide, Kohji; Kanaya, Haruyuki.

1978-01-01

55 out of 62 patients with cerebral infarction were investigated in terms of CT scan findings, angiographic findings, and clinical symptoms. The results obtained were as follows: 1) The low-density areas of the CT scan findings were classified into the following four types: large hemispheric or lobular --Type I; wedge-shaped --Type II; small --Type III; and lacunar low-density area. --Type IV. 2) Almost all patients with angiographically occlusive findings showed low-density areas of Type I; however, one patient with ICA occlusion revealed only a lacunar low-density area. 3) The patients with lacunar low-density areas showed an angiographically delayed filling of the angular artery and posterior parietal artery of the middle cerebral artery. 4) The relationship between the types of low-density areas and the clinical conscious disorders was not clear. On the other hand, the patients with Type I low-density areas almost all had motor disturbances, while patients with other types of low-density areas showed only 60 - 70% motor disturbances. 5) In patients with speech disorders, total aphasia cases were found in patients with large hemispheric low-density areas on the left side. Although, motor aphasia cases were seen in patients with various low-density areas on the left inferior frontal and precentral gyri, dysarthria cases were found in the patients with several low-density areas on both sides. 6) The localization of lacunar low-density areas seemed to be near the caudate nucleus on the right side and in the putaminal regions on the left side. The mean and the standard deviation of CT numbers in the lacunar low-density areas showed higher values on the right side than on the left side. (author)

Land use and land cover mapping: City of Palm Bay, Florida

Science.gov (United States)

Barile, D. D.; Pierce, R.

1977-01-01

Two different computer systems were compared for use in making land use and land cover maps. The Honeywell 635 with the LANDSAT signature development program (LSDP) produced a map depicting general patterns, but themes were difficult to classify as specific land use. Urban areas were unclassified. The General Electric Image 100 produced a map depicting eight land cover categories classifying 68 percent of the total area. Ground truth, LSDP, and Image 100 maps were all made to the same scale for comparison. LSDP agreed with the ground truth 60 percent and 64 percent within the two test areas compared and Image 100 was in agreement 70 percent and 80 percent.

Aboveground Net Primary Production of tree cover at the post-disturbance area in the Tatra National Park, Slovakia

Directory of Open Access Journals (Sweden)

Konôpka Bohdan

2015-09-01

Full Text Available Large-scale disturbances under the conditions of Slovakia, caused especially by storm and bark beetle, bring dramatic decline in carbon budget of the country, besides other negative consequences. The largest disturbance in modern history of the Slovak forestry was the storm damage that occurred in November 2004. The Tatra National Park (TNP was one of the most affected regions. Thus, in this territory, two transects (T1 – the Danielov dom site and T2 – near the Horný Smokovec village were established to survey basic dendrometric properties of trees in young stands established after the disaster. The standing stock of aboveground biomass in tree cover for the spring and autumn 2014 was calculated using the recorded variables, i.e. tree height and diameter measured at the stem base, together with the region-specific allometric relations. Then, the Aboveground Net Primary Production (ANPP in tree cover was estimated with respect to its components (stem, branches and foliage. ANPP was 315 g m−2 per year (Transect T1, and 391 g m−2 per year (Transect T2. The differences in the structure of ANPP, i.e. contribution of tree components, were found between transects T1 and T2. They were caused by the contrasting tree species composition, specifically the ratios between Norway spruce and broadleaved species. Broadleaves allocated more biomass production to foliage than spruce. This phenomenon together with higher turnover (once a year of foliage caused that broadleaves manifest higher share of fast-cycling carbon in comparison to the amount of carbon sequestrated in woody parts (stem and branches. High variability of ANPP was found within the transects, i.e. among the plots (microsites. As for the representative estimation of the standing stock of aboveground part of tree cover as well as ANPP at the post-disturbance area in the TNP territory, the survey should be performed on a net of research plots. Only this approach enables reliable estimates

Ecosystem services from converted land: the importance of tree cover in Amazonian pastures

Science.gov (United States)

Barrett, Kirsten; Valentim, Judson; Turner, B. L.

2013-01-01

Deforestation is responsible for a substantial fraction of global carbon emissions and changes in surface energy budgets that affect climate. Deforestation losses include wildlife and human habitat, and myriad forest products on which rural and urban societies depend for food, fiber, fuel, fresh water, medicine, and recreation. Ecosystem services gained in the transition from forests to pasture and croplands, however, are often ignored in assessments of the impact of land cover change. The role of converted lands in tropical areas in terms of carbon uptake and storage is largely unknown. Pastures represent the fastest-growing form of converted land use in the tropics, even in some areas of rapid urban expansion. Tree biomass stored in these areas spans a broad range, depending on tree cover. Trees in pasture increase carbon storage, provide shade for cattle, and increase productivity of forage material. As a result, increasing fractional tree cover can provide benefits land managers as well as important ecosystem services such as reducing conversion pressure on forests adjacent to pastures. This study presents an estimation of fractional tree cover in pasture in a dynamic region on the verge of large-scale land use change. An appropriate sampling interval is established for similar studies, one that balances the need for independent samples of sufficient number to characterize a pasture in terms of fractional tree cover. This information represents a useful policy tool for government organizations and NGOs interested in encouraging ecosystem services on converted lands. Using high spatial resolution remotely sensed imagery, fractional tree cover in pasture is quantified for the municipality of Rio Branco, Brazil. A semivariogram and devolving spatial resolution are employed to determine the coarsest sampling interval that may be used, minimizing effects of spatial autocorrelation. The coarsest sampling interval that minimizes spatial dependence was about 22 m. The

Hydrograph sensitivity to estimates of map impervious cover: a WinHSPF BASINS case study

Science.gov (United States)

Endreny, Theodore A.; Somerlot, Christopher; Hassett, James M.

2003-04-01

The BASINS geographic information system hydrologic toolkit was designed to compute total maximum daily loads, which are often derived by combining water quantity estimates with pollutant concentration estimates. In this paper the BASINS toolkit PLOAD and WinHSPF sub-models are briefly described, and then a 0·45 km2 headwater watershed in the New York Croton River area is used for a case study illustrating a full WinHSPF implementation. The goal of the Croton study was to determine the sensitivity of WinHSPF hydrographs to changes in land cover map inputs. This scenario occurs when scaling the WinHSPF model from the smaller 0·45 km2 watershed to the larger 1000 km2 management basin of the entire Croton area. Methods used to test model sensitivity include first calibrating the WinHSPF hydrograph using research-monitored precipitation and discharge data together with high spatial resolution and accuracy land cover data of impervious and pervious areas, and then swapping three separate land cover files, known as GIRAS, MRLC, and DOQQ data, into the calibrated model. Research results indicated that the WinHSPF land cover swapping had peak flow sensitivity in December 2001 hydrographs between 35% underestimation and 20% overestimation, and that errors in land-cover-derived runoff ratios for storm totals and peak flows tracked with the land cover data estimates of impervious area.

Investigation of accuracy of CORINE 2006 land cover data used in watershed studies

Directory of Open Access Journals (Sweden)

Ayhan Ateşoğlu

2016-01-01

Full Text Available There have been many studies concerning the use of sustainable natural resources. The planning concerning the results of watershed-based studies is made for the future. The issue to be considered in these studies, is obtaining accurate data. The most important data of the studies in the watershed basin is obtaining land cover/use data. Land cover / land classification done by using remote sensing and GIS and monitoring the change periodically are both easy and economical. To this end, CORINE (Coordination of Information on the Environment land cover program was initiated by The European Commission (CEC. The accuracy of CORINE 2006 land cover data was evaluated using high resolution Google Earth data in two separate test areas located in the Black Sea and Central Anatolia region. Random 5000 points for each test area were assigned to classes according to the CORINE classification method using Google Earth and were compared with the CORINE 2006 data. The accuracy of first test area in Black Sea region was calculated as 51.80% the accuracy of second test area in Central Anatolia region was calculated as 55.32%. For each test area, CORINE 2006 data has not been found to be up to date and has been detected to have low accuracy.

Multi-temporal Assessment of Forest Cover, Stocking parameters ...

African Journals Online (AJOL)

user

The study assessed forest cover, stocking parameters and above-ground tree .... deration new emerging ideas on REDD+, this study .... representing areas of change and zero values representing no ..... John Wiley & Sons, Inc. New York.

Changes in Vegetation Cover in Reforested Areas in the State of São Paulo, Brazil and the Implication for Landslide Processes

Directory of Open Access Journals (Sweden)

Regina Célia dos Santos Alvalá

2012-09-01

Full Text Available In Brazil, plantations of exotic species such as Eucalyptus have expanded substantially in recent years, due in large part to the great demand for cellulose and wood. The combination of the steep slopes in some of these regions, such as the municipalities located close to the Serra do Mar and Serra da Mantiqueira, and the soil exposure that occurs in some stages in the Eucalyptus cultivation cycle, can cause landslides. The use of a geographic information system (GIS assists with the identification of areas that are susceptible to landslides, and one of the GIS tools used is the spatial inference technique. In this work, the landslide susceptibility of areas occupied by Eucalyptus plantations in different stages of development in municipalities in the state of São Paulo was examined. Eight thematic maps were used, and, the fuzzy gamma technique was used for data integration and the generation of susceptibility maps, in which scenarios were created with different gamma values for the dry and rainy seasons. The results for areas planted with Eucalyptus were compared with those obtained for other land uses and covers. In the moderate and high susceptibility classes, the pasture is the land use type that presented the greatest susceptibility, followed by new Eucalyptus plantations and urban areas.

Climatological determinants of woody cover in Africa.

Science.gov (United States)

Good, Stephen P; Caylor, Kelly K

2011-03-22

Determining the factors that influence the distribution of woody vegetation cover and resolving the sensitivity of woody vegetation cover to shifts in environmental forcing are critical steps necessary to predict continental-scale responses of dryland ecosystems to climate change. We use a 6-year satellite data record of fractional woody vegetation cover and an 11-year daily precipitation record to investigate the climatological controls on woody vegetation cover across the African continent. We find that-as opposed to a relationship with only mean annual rainfall-the upper limit of fractional woody vegetation cover is strongly influenced by both the quantity and intensity of rainfall events. Using a set of statistics derived from the seasonal distribution of rainfall, we show that areas with similar seasonal rainfall totals have higher fractional woody cover if the local rainfall climatology consists of frequent, less intense precipitation events. Based on these observations, we develop a generalized response surface between rainfall climatology and maximum woody vegetation cover across the African continent. The normalized local gradient of this response surface is used as an estimator of ecosystem vegetation sensitivity to climatological variation. A comparison between predicted climate sensitivity patterns and observed shifts in both rainfall and vegetation during 2009 reveals both the importance of rainfall climatology in governing how ecosystems respond to interannual fluctuations in climate and the utility of our framework as a means to forecast continental-scale patterns of vegetation shifts in response to future climate change.

Characterizing Degradation Gradients through Land Cover Change Analysis in Rural Eastern Cape, South Africa

Directory of Open Access Journals (Sweden)

Zahn Münch

2017-02-01

Full Text Available Land cover change analysis was performed for three catchments in the rural Eastern Cape, South Africa, for two time steps (2000 and 2014, to characterize landscape conversion trajectories for sustained landscape health. Land cover maps were derived: (1 from existing data (2000; and (2 through object-based image analysis (2014 of Landsat 8 imagery. Land cover change analysis was facilitated using land cover labels developed to identify landscape change trajectories. Land cover labels assigned to each intersection of the land cover maps at the two time steps provide a thematic representation of the spatial distribution of change. While land use patterns are characterized by high persistence (77%, the expansion of urban areas and agriculture has occurred predominantly at the expense of grassland. The persistence and intensification of natural or invaded wooded areas were identified as a degradation gradient within the landscape, which amounted to almost 10% of the study area. The challenge remains to determine significant signals in the landscape that are not artefacts of error in the underlying input data or scale of analysis. Systematic change analysis and accurate uncertainty reporting can potentially address these issues to produce authentic output for further modelling.

Analysis of land cover/use changes using Landsat 5 TM data and indices.

Science.gov (United States)

Ettehadi Osgouei, Paria; Kaya, Sinasi

2017-04-01

Urban expansion and unprecedented rural to urban transition, along with a huge population growth, are major driving forces altering land cover/use in metropolitan areas. Many of the land cover classes such as farmlands, wetlands, forests, and bare soils have been transformed during the past years into human settlements. Identification of the city growth trends and the impact of it on the vegetation cover of an area is essential for a better understanding of the sustainability of urban development processes, both planned and unplanned. Analyzing the causes and consequences of land use dynamics helps local government, urban planners, and managers for the betterment of future plans and minimizing the negative effects.This study determined temporal changes in vegetation cover and built-up area in Istanbul (Turkey) using the normalized difference vegetation index (NDVI), soil-adjusted vegetation index (SAVI), and built-up area index (BUAI). The temporal data were based on Landsat 5 Thematic Mapper (TM) images acquired in June of 1984, 2002, 2007, 2009, and 2011. The NDVI was applied to all the Landsat images, and the resulting NDVI images were overlaid to generate an NDVI layer stack image. The same procedure was repeated using the SAVI and BUAI images. The layer stack images revealed those areas that had changed in terms of the different indices over the years. To determine temporal change trends, the values of 150 randomly selected control points were extracted from the same locations in the NDVI, SAVI, and BUAI layer stack images. The results obtained from these control points showed that vegetation cover decreased considerably because of a remarkable increase in the built-up area.

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

Science.gov (United States)

Yeo, In-Young; Lee, Sangchui; Sadeghi, Ali M.; Beeson, Peter C.; Hively, W. Dean; McCarty, Greg W.; Lang, Megan W.

2013-01-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991–2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha−1, but it decreased to 4.6–10.1 kg ha−1 with winter cover crops resulting in a reduction rate of 27–67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha−1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils

Study on Resources Assessment of Coal Seams covered by Long-Distance Oil & Gas Pipelines

Science.gov (United States)

Han, Bing; Fu, Qiang; Pan, Wei; Hou, Hanfang

2018-01-01

The assessment of mineral resources covered by construction projects plays an important role in reducing the overlaying of important mineral resources and ensuring the smooth implementation of construction projects. To take a planned long-distance gas pipeline as an example, the assessment method and principles for coal resources covered by linear projects are introduced. The areas covered by multiple coal seams are determined according to the linear projection method, and the resources covered by pipelines directly and indirectly are estimated by using area segmentation method on the basis of original blocks. The research results can provide references for route optimization of projects and compensation for mining right..

Final covering of the Ronneburg uranium mining site

International Nuclear Information System (INIS)

Hoepfner, Uwe

2007-01-01

The rehabilitation of WISMUT's former Ronneburg uranium mining site involves backfilling of waste rock to the Lichtenberg open pit. The relocation project comprises about 110 million m 3 of sulphide-bearing and AMD-generating waste rock which makes it the most important and most cost-intensive single surface restoration project conducted by WISMUT at the Ronneburg site. The backfilled waste rock has to be covered on an area of about 220 ha to control water infiltration and gas diffusion. Design planning for the final cover placement which began in 2004 had to be based on a comprehensive cost-benefit analysis as well on field tests of alternative cover options which are in compliance with legal requirements. An intensive testing program concerning the vadose zone of soil covers has therefore been started in 2000. The paper presents an overview of the monitoring program and the results of the vadose zone measurements. The water of soil covers have to be predicted for extended evaluation periods. Therefore water balance simulations of single layer covers (storage and evaporation concept) taking current and future soil and climate conditions into account are performed with the HYDRUS 2D code. (author)

Land Cover - Minnesota Land Cover Classification System

Data.gov (United States)

Minnesota Department of Natural Resources — Land cover data set based on the Minnesota Land Cover Classification System (MLCCS) coding scheme. This data was produced using a combination of aerial photograph...

Improving snow cover mapping in forests through the use of a canopy reflectance model

International Nuclear Information System (INIS)

Klein, A.G.; Hall, D.K.; Riggs, G.A.

1998-01-01

MODIS, the moderate resolution imaging spectro radiometer, will be launched in 1998 as part of the first earth observing system (EOS) platform. Global maps of land surface properties, including snow cover, will be created from MODIS imagery. The MODIS snow-cover mapping algorithm that will be used to produce daily maps of global snow cover extent at 500 m resolution is currently under development. With the exception of cloud cover, the largest limitation to producing a global daily snow cover product using MODIS is the presence of a forest canopy. A Landsat Thematic Mapper (TM) time-series of the southern Boreal Ecosystem–Atmosphere Study (BOREAS) study area in Prince Albert National Park, Saskatchewan, was used to evaluate the performance of the current MODIS snow-cover mapping algorithm in varying forest types. A snow reflectance model was used in conjunction with a canopy reflectance model (GeoSAIL) to model the reflectance of a snow-covered forest stand. Using these coupled models, the effects of varying forest type, canopy density, snow grain size and solar illumination geometry on the performance of the MODIS snow-cover mapping algorithm were investigated. Using both the TM images and the reflectance models, two changes to the current MODIS snow-cover mapping algorithm are proposed that will improve the algorithm's classification accuracy in forested areas. The improvements include using the normalized difference snow index and normalized difference vegetation index in combination to discriminate better between snow-covered and snow-free forests. A minimum albedo threshold of 10% in the visible wavelengths is also proposed. This will prevent dense forests with very low visible albedos from being classified incorrectly as snow. These two changes increase the amount of snow mapped in forests on snow-covered TM scenes, and decrease the area incorrectly identified as snow on non-snow-covered TM scenes. (author)

An airborne gamma ray snow survey of a forest covered area with a deep snowpack

International Nuclear Information System (INIS)

Glynn, J.E.; Carroll, T.R.; Holman, P.B.; Grasty, R.L.

1988-01-01

Problems arising from the airborne gamma ray measurement of snow water equivalent over a forest covered deep snowpack are examined. The principal sources of error are believed to be due to the radioactivity in the biomass and to variability in the snow cover. A theoretical model is developed to correct the airborne measurements for these sources of error. The application of the theory to data collected over the St. John River Basin, located in the eastern part of Canada and the United States, is found to significantly improve the airborne results

Perch availability and ground cover: factors that may constitute ...

African Journals Online (AJOL)

In Succulent Karoe, pale chanting goshawks occupied areas where perch density (16 natural and 122 artificial/25 hal was significantly higher than in unoccupied areas (8 natural and 12 artificial/25 hal. The high proportion of cover formed by natural perches (trees and shrubs; 36%) and the low proportion of open ground ...

Natural Vegetation of the Flora area

DEFF Research Database (Denmark)

Sebsebe, Demissew; Friis, Ib

2009-01-01

A review article summarising the recent ideas about the natural vegetation in the area covered by the Flora of Ethiopia and Eritrea......A review article summarising the recent ideas about the natural vegetation in the area covered by the Flora of Ethiopia and Eritrea...

Comparison of Covered Versus Uncovered Stents for Benign Superior Vena Cava (SVC) Obstruction.

Science.gov (United States)

Haddad, Mustafa M; Simmons, Benjamin; McPhail, Ian R; Kalra, Manju; Neisen, Melissa J; Johnson, Matthew P; Stockland, Andrew H; Andrews, James C; Misra, Sanjay; Bjarnason, Haraldur

2018-05-01

To identify whether long-term symptom relief and stent patency vary with the use of covered versus uncovered stents for the treatment of benign SVC obstruction. We retrospectively identified all patients with benign SVC syndrome treated to stent placement between January 2003 and December 2015 (n = 59). Only cases with both clinical and imaging follow-up were included (n = 47). In 33 (70%) of the patients, the obstruction was due to a central line or pacemaker wires, and in 14 (30%), the cause was fibrosing mediastinitis. Covered stents were placed in 17 (36%) of the patients, and 30 (64%) patients had an uncovered stent. Clinical and treatment outcomes, complications, and the percent stenosis of each stent were evaluated. Technical success was achieved in all cases at first attempt. Average clinical and imaging follow-up in years was 2.7 (range 0.1-11.1) (covered) and 1.7 (range 0.2-10.5) (uncovered), respectively. There was a significant difference (p = 0.044) in the number of patients who reported a return of symptoms between the covered (5/17 or 29.4%) and uncovered (18/30 or 60%) groups. There was also a significant difference (p = stenosis after stent placement between the covered [17.9% (range 0-100) ± 26.2] and uncovered [48.3% (range 6.8-100) ± 33.5] groups. No significant difference (p = 0.227) was found in the time (days) between the date of the procedure and the date of clinical follow-up where a return of symptoms was reported [covered: 426.6 (range 28-1554) ± 633.9 and uncovered 778.1 (range 23-3851) ± 1066.8]. One patient in the uncovered group had non-endovascular surgical intervention (innominate to right atrial bypass), while none in the covered group required surgical intervention. One major complication (SIR grade C) occurred that consisted of a pericardial hemorrhagic effusion after angioplasty that required covered stent placement. There were no procedure-related deaths. Both covered and uncovered stents can be used for

Towards Seamless Validation of Land Cover Data

Science.gov (United States)

Chuprikova, Ekaterina; Liebel, Lukas; Meng, Liqiu

2018-05-01

This article demonstrates the ability of the Bayesian Network analysis for the recognition of uncertainty patterns associated with the fusion of various land cover data sets including GlobeLand30, CORINE (CLC2006, Germany) and land cover data derived from Volunteered Geographic Information (VGI) such as Open Street Map (OSM). The results of recognition are expressed as probability and uncertainty maps which can be regarded as a by-product of the GlobeLand30 data. The uncertainty information may guide the quality improvement of GlobeLand30 by involving the ground truth data, information with superior quality, the know-how of experts and the crowd intelligence. Such an endeavor aims to pave a way towards a seamless validation of global land cover data on the one hand and a targeted knowledge discovery in areas with higher uncertainty values on the other hand.

Land cover change interacts with drought severity to change fire regimes in Western Amazonia.

Science.gov (United States)

Gutiérrez-Vélez, Víctor H; Uriarte, María; DeFries, Ruth; Pinedo-Vásquez, Miguel; Fernandes, Katia; Ceccato, Pietro; Baethgen, Walter; Padoch, Christine

Fire is becoming a pervasive driver of environmental change in Amazonia and is expected to intensify, given projected reductions in precipitation and forest cover. Understanding of the influence of post-deforestation land cover change on fires in Amazonia is limited, even though fires in cleared lands constitute a threat for ecosystems, agriculture, and human health. We used MODIS satellite data to map burned areas annually between 2001 and 2010. We then combined these maps with land cover and climate information to understand the influence of land cover change in cleared lands and dry-season severity on fire occurrence and spread in a focus area in the Peruvian Amazon. Fire occurrence, quantified as the probability of burning of individual 232-m spatial resolution MODIS pixels, was modeled as a function of the area of land cover types within each pixel, drought severity, and distance to roads. Fire spread, quantified as the number of pixels burned in 3 × 3 pixel windows around each focal burned pixel, was modeled as a function of land cover configuration and area, dry-season severity, and distance to roads. We found that vegetation regrowth and oil palm expansion are significantly correlated with fire occurrence, but that the magnitude and sign of the correlation depend on drought severity, successional stage of regrowing vegetation, and oil palm age. Burning probability increased with the area of nondegraded pastures, fallow, and young oil palm and decreased with larger extents of degraded pastures, secondary forests, and adult oil palm plantations. Drought severity had the strongest influence on fire occurrence, overriding the effectiveness of secondary forests, but not of adult plantations, to reduce fire occurrence in severely dry years. Overall, irregular and scattered land cover patches reduced fire spread but irregular and dispersed fallows and secondary forests increased fire spread during dry years. Results underscore the importance of land cover

Pharmacotherapeutic approaches for treating psoriasis in difficult-to-treat areas.

Science.gov (United States)

Kivelevitch, Dario; Frieder, Jillian; Watson, Ian; Paek, So Yeon; Menter, M Alan

2018-04-01

Despite great therapeutic advancements in psoriasis, four notable difficult-to-treat areas including the scalp, nails, intertriginous (including genitals), and palmoplantar regions, pose a challenge to both physicians and patients. Localized disease of these specific body regions inflicts a significant burden on patients' quality of life and requires an adequate selection of treatments. Areas covered: This manuscript discusses appropriate therapies and important treatment considerations for these difficult-to-treat areas based on the available clinical data from the literature. Expert opinion: Clinical trials assessing therapies for the difficult-to-treat areas have been inadequate. With the first biological clinical trial for genital psoriasis pending publication, it is with hope that other biological agents will be evaluated for region-specific psoriasis. A greater understanding of the genetic and immunologic aspects of regional psoriasis, as well as identification of unique biomarkers, will further guide management decisions. For example, the recent discovery of the IL-36 receptor gene for generalized pustular psoriasis may prove valuable for other forms of psoriasis. Ultimately, identification of the most beneficial treatments for each psoriasis subtype and difficult-to-treat area will provide patients with maximal quality of life.

Standard land-cover classification scheme for remote-sensing applications in South Africa

CSIR Research Space (South Africa)

Thompson, M

1996-01-01

Full Text Available For large areas, satellite remote-sensing techniques have now become the single most effective method for land-cover and land-use data acquisition. However, the majority of land-cover (and land-use) classification schemes used have been developed...

Depositional characteristics of cretaceous cover in Xiangyangshan area of Heilongjiang province and analysis on prospect for sandstone hosted interlayer oxidation zone type uranium deposits

International Nuclear Information System (INIS)

Cai Yuqi; Li Shengxiang; Dong Wenming

2003-01-01

The depositional systems and characteristics of Cretaceous Cover depositional facies are discussed. In combination with logging curves in Xiangyangshan area, two depositional systems (namely, alluvial fan depositional system and alluvial plain depositional system) and five types of depositional facies are distinguished. Results of detailed research are given for each depositional facies in aspects of lithology, depositional structure, logging curve and grain size distribution pattern. Temporal and spatial distribution features of the depositional facies and the development features of interlayer oxidation zones of the second member of Quantou Formation are analyzed. Finally, conclusions on prospects for sandstone-hosted interlayer oxidation zone type uranium deposits in the study area are given in the aspect of depositional facies. (authors)

Therapeutic evaluation of retrievable esophageal covered stent in treating achalasia

International Nuclear Information System (INIS)

Li Yuwei; Zhang Fuqiang; Yuan Liang; Li Yunhui; Luo Bin; Yu Li; Sun Dingqiang

2010-01-01

Objective: To evaluate the clinical effect of retrievable esophageal covered metal internal stent in treating patients with achalasia. Methods: Under DSA guidance, peroral 'Z-type' double horn covered metal internal stent implantation was performed in 16 patients with achalasia. Esophagography was carried out about 28 days after the procedure and the stent was retrieved. Results: Of 16 cases, the stent fell off into the stomach two weeks after the operation in one. And the stent was successfully replaced after it was taken out. The placed stent was successfully retrieved in all cases 28 days after the treatment. No serious complications occurred. All the patients were followed up for 3 months to 3 years. During the follow-up period restenosis of the esophagus developed in two cases (at one and 1.5 years respectively), and the restenosis degree was relived after balloon dilation. Clinically, no esophageal symptoms, such as dysphagia, occurred in all patients. Conclusion: As a simple and safe technique, the retrievable esophageal covered metal internal stent implantation is very effective with fewer complications for the treatment of achalasia. Moreover, the technique carries lower restenosis occurrence. (authors)

Characteristics of snow cover duration across the northeast United States of America

Science.gov (United States)

Leathers, Daniel J.; Luff, Barbara L.

1997-11-01

The presence or absence of a snow cover affects a myriad of environmental and societal systems through its modification of the surface radiation balance and its ultimate impact on near-surface air temperatures. Daily snow cover data were collected for a network of 91 stations covering the northeast USA from Maine, south through to West Virginia. The snow cover data along with ancillary temperature, snowfall and precipitation data were used to investigate the characteristics of snow cover duration in this region and the effects of the snow cover on boundary layer climate variables for the snow cover seasons 1948-1949 through to 1987-1988.Results indicate that snow cover duration is variable in both space and time. The duration of a snow cover of 2.5 cm or greater varies from greater than 100 days in northern New England to less than 20 days across areas of Delaware, Maryland and West Virginia. Temporally, snow cover duration for the region as a whole was very short from the late 1940s through to the mid-1950s. From the late 1950s to the end of the period snow cover duration has varied around a consistent mean value. No long-term trends in snow cover duration are apparent in the record for the northeast USA.Principal components analysis and clustering techniques were utilized to isolate spatially coherent regions in which snow cover duration has varied similarly over the period of record. This analysis resulted in the identification of four snow-cover-duration regions across the northeast USA: including (i) the West Virginia area, (ii) the mid-Atlantic from southern New England through to western Pennsylvania, (iii) western and central New York and (iv) northern New England. Snow cover duration is shown to be highly associated with snowfall and temperature but not strongly related to total liquid precipitation. The intra-annual variability of snow cover duration is also investigated for each region.

Application of spectrometer cropscan MSR 16R and Landsat imagery for identification the spectral characteristics of land cover

Science.gov (United States)

Tampubolon, Togi; Abdullah, Khiruddin bin; San, Lim Hwee

2013-09-01

The spectral characteristics of land cover are basic references in classifying satellite image for geophysics analysis. It can be obtained from the measurements using spectrometer and satellite image processing. The aims of this study to investigate the spectral characteristics of land cover based on the results of measurement using Spectrometer Cropscan MSR 16R and Landsat satellite imagery. The area of study in this research is in Medan, (Deli Serdang, North Sumatera) Indonesia. The scope of this study is the basic survey from the measurements of spectral land cover which is covered several type of land such as a cultivated and managed terrestrial areas, natural and semi-natural, cultivated aquatic or regularly flooded areas, natural and semi-natural aquatic, artificial surfaces and associated areas, bare areas, artificial waterbodies and natural waterbodies. The measurement and verification were conducted using a spectrometer provided their spectral characteristics and Landsat imagery, respectively. The results of the spectral characteristics of land cover shows that each type of land cover have a unique characteristic. The correlation of spectral land cover based on spectrometer Cropscan MSR 16R and Landsat satellite image are above 90 %. However, the land cover of artificial waterbodiese have a correlation under 40 %. That is because the measurement of spectrometer Cropscan MSR 16R and acquisition of Landsat satellite imagery has a time different.

Effects of Forest Cover Change on Flood Characteristics in the Upper Citarum Watershed

Directory of Open Access Journals (Sweden)

Bambang Dwi Dasanto

2014-12-01

Full Text Available Information on the effect of forest cover changes on streamflow (river discharge in large-scale catchment is important to be studied. The rate of forest cover change in the Upper Citarum Watershed as a large-scale catchment is high enough to drive streamflow change, such as increase of discharge level, or flood volume. Within the research area, flood would occur when the volume of streamflow exceeded the canal capacity and inundated areas that were normally dry. Therefore, this research focused on identifying the effects of forest cover change on flood events and its distribution. The research consisted of 2 main stages; firstly, building geometric data of river and performing frequency analysis of historical and scenario discharges using an approach of probability distribution; and, secondly, flood inundation mapping using HEC-RAS model. The results showed that forest reduction have affected water yield in the downstream of Upper Citarum Watershed. In each return period, this reduction have increased river discharge level and affected the spread of flooded areas. In 2-year return period, the extent of flood as an impact of forest reduction was estimated to decrease slowly. However, in the return period of more than 2 years, the spread of flooded areas increased sharply. These proved that forest cover reduction would always increase the discharge value, but it did not always expand the inundated area.

Safety and Efficacy of Percutaneous Biliary Covered Stent Placement in Patients with Malignant Biliary Hilar Obstruction; Correlation with Liver Function

Energy Technology Data Exchange (ETDEWEB)

Hyun, Hyeran; Choi, Sun Young, E-mail: medmath@hanmail.net [School of Medicine Ewha Womans University, Department of Radiology and Medical Research Institute (Korea, Republic of); Kim, Kyung Ah [St. Vincent’s Hospital, The Catholic University of Korea, Department of Radiology (Korea, Republic of); Ko, Soo Bin [College of Arts and Science Case Western Reserve University, Department of Biology (United States)

2016-09-15

PurposeTo estimate the safety and efficacy of percutaneous ePTFE-covered biliary stent placement and the relationship between underlying liver function and stent patency in patients with malignant hilar obstruction.Materials and MethodsFrom March 2012 to June 2015, 41 patients [22 females, 19 males; mean age 69.8 (range 34–94) years] with malignant biliary obstruction underwent percutaneous biliary stent placement (31 patients with unilateral, 10 patients with bilateral side-by-side). Cumulative patient survival and stent patency rate curves were derived using the Kaplan–Meier method. A Cox model was used to explore the relationship between liver function and patient survival, and also biliary stent patency. Pearson correlation coefficient was used to analyze the relationship between patient survival and stent patency.ResultsTechnical success rate was 100 % and clinical success rate was 95 %. During follow-up, four complications occurred (two bilomas and two cases of acute cholecystitis) and were treated successfully with percutaneous drainage. No other complication occurred. Mean serum bilirubin level was 11.34 ± 7.35 mg/dL before drainage and 5.00 ± 4.83 mg/dL 2 weeks after stent placement. The median patent survival duration was 147 days (95 % CI, 69.6–224.4 days). The median stent patency duration was 101 days (95 % CI, 70.0–132.0 days). The cumulative stent patency rates at 1, 3, 6, and 12 months were 97, 57.6, 30.3, and 17.0 %, respectively. Child–Pugh score was correlated significantly with patient survival (P = 0.011) and stent patency (P = 0.007). MELD score was correlated significantly with stent patency (P = 0.044). There was a correlation between patient survival and stent patency (r = 0.778, P < 0.001).ConclusionPercutaneous placement of ePTFE-covered biliary stent was a safe and an effective method for malignant biliary obstruction. Underlying liver function seemed to be one of the important factors affecting

Safety and Efficacy of Percutaneous Biliary Covered Stent Placement in Patients with Malignant Biliary Hilar Obstruction; Correlation with Liver Function

International Nuclear Information System (INIS)

Hyun, Hyeran; Choi, Sun Young; Kim, Kyung Ah; Ko, Soo Bin

2016-01-01

PurposeTo estimate the safety and efficacy of percutaneous ePTFE-covered biliary stent placement and the relationship between underlying liver function and stent patency in patients with malignant hilar obstruction.Materials and MethodsFrom March 2012 to June 2015, 41 patients [22 females, 19 males; mean age 69.8 (range 34–94) years] with malignant biliary obstruction underwent percutaneous biliary stent placement (31 patients with unilateral, 10 patients with bilateral side-by-side). Cumulative patient survival and stent patency rate curves were derived using the Kaplan–Meier method. A Cox model was used to explore the relationship between liver function and patient survival, and also biliary stent patency. Pearson correlation coefficient was used to analyze the relationship between patient survival and stent patency.ResultsTechnical success rate was 100 % and clinical success rate was 95 %. During follow-up, four complications occurred (two bilomas and two cases of acute cholecystitis) and were treated successfully with percutaneous drainage. No other complication occurred. Mean serum bilirubin level was 11.34 ± 7.35 mg/dL before drainage and 5.00 ± 4.83 mg/dL 2 weeks after stent placement. The median patent survival duration was 147 days (95 % CI, 69.6–224.4 days). The median stent patency duration was 101 days (95 % CI, 70.0–132.0 days). The cumulative stent patency rates at 1, 3, 6, and 12 months were 97, 57.6, 30.3, and 17.0 %, respectively. Child–Pugh score was correlated significantly with patient survival (P = 0.011) and stent patency (P = 0.007). MELD score was correlated significantly with stent patency (P = 0.044). There was a correlation between patient survival and stent patency (r = 0.778, P < 0.001).ConclusionPercutaneous placement of ePTFE-covered biliary stent was a safe and an effective method for malignant biliary obstruction. Underlying liver function seemed to be one of the important factors affecting

Land cover changes and greenhouse gas emissions in two different soil covers in the Brazilian Caatinga.

Science.gov (United States)

Ribeiro, Kelly; Sousa-Neto, Eráclito Rodrigues de; Carvalho, João Andrade de; Sousa Lima, José Romualdo de; Menezes, Rômulo Simões Cezar; Duarte-Neto, Paulo José; da Silva Guerra, Glauce; Ometto, Jean Pierre Henry Baulbaud

2016-11-15

The Caatinga biome covers an area of 844,453km(2) and has enormous endemic biodiversity, with unique characteristics that make it an exclusive Brazilian biome. It falls within the earth's tropical zone and is one of the several important ecoregions of Brazil. This biome undergoes natural lengthy periods of drought that cause losses in crop and livestock productivity, having a severe impact on the population. Due to the vulnerability of this ecosystem to climate change, livestock has emerged as the main livelihood of the rural population, being the precursor of the replacement of native vegetation by grazing areas. This study aimed to measure GHG emissions from two different soil covers: native forest (Caatinga) and pasture in the municipality of São João, Pernambuco State, in the years 2013 and 2014. GHG measurements were taken by using static chamber techniques in both soil covers. According to a previous search, so far, this is the first study measuring GHG emissions using the static chamber in the Caatinga biome. N2O emissions ranged from -1.0 to 4.2mgm(-2)d(-1) and -1.22 to 3.4mgm(-2)d(-1) in the pasture and Caatinga, respectively, and they did not significantly differ from each other. Emissions were significantly higher during dry seasons. Carbon dioxide ranged from -1.1 to 14.1 and 1.2 to 15.8gm(-2)d(-1) in the pasture and Caatinga, respectively. CO2 emissions were higher in the Caatinga in 2013, and they were significantly influenced by soil temperature, showing an inverse relation. Methane emission ranged from 6.6 to 6.8 and -6.0 to 4.8mgm(-2)d(-1) in the pasture and Caatinga, respectively, and was significantly higher only in the Caatinga in the rainy season of 2014. Soil gas fluxes seemed to be influenced by climatic and edaphic conditions as well as by soil cover in the Caatinga biome. Copyright © 2016 Elsevier B.V. All rights reserved.

Improving automated disturbance maps using snow-covered landsat time series stacks

Science.gov (United States)

Kirk M. Stueve; Ian W. Housman; Patrick L. Zimmerman; Mark D. Nelson; Jeremy Webb; Charles H. Perry; Robert A. Chastain; Dale D. Gormanson; Chengquan Huang; Sean P. Healey; Warren B. Cohen

2012-01-01

Snow-covered winter Landsat time series stacks are used to develop a nonforest mask to enhance automated disturbance maps produced by the Vegetation Change Tracker (VCT). This method exploits the enhanced spectral separability between forested and nonforested areas that occurs with sufficient snow cover. This method resulted in significant improvements in Vegetation...

Land Cover Classification Using ALOS Imagery For Penang, Malaysia

International Nuclear Information System (INIS)

Sim, C K; Abdullah, K; MatJafri, M Z; Lim, H S

2014-01-01

This paper presents the potential of integrating optical and radar remote sensing data to improve automatic land cover mapping. The analysis involved standard image processing, and consists of spectral signature extraction and application of a statistical decision rule to identify land cover categories. A maximum likelihood classifier is utilized to determine different land cover categories. Ground reference data from sites throughout the study area are collected for training and validation. The land cover information was extracted from the digital data using PCI Geomatica 10.3.2 software package. The variations in classification accuracy due to a number of radar imaging processing techniques are studied. The relationship between the processing window and the land classification is also investigated. The classification accuracies from the optical and radar feature combinations are studied. Our research finds that fusion of radar and optical significantly improved classification accuracies. This study indicates that the land cover/use can be mapped accurately by using this approach

High spatial resolution mapping of the Cerrado's land cover and land use types in the priority area for conservation Chapada da Contagem, Brazil.

Science.gov (United States)

Ribeiro, F.; Roberts, D. A.; Davis, F. W.; Antunes Daldegan, G.; Nackoney, J.; Hess, L. L.

2016-12-01

The Brazilian savanna, Cerrado, is the second largest biome over South America and the most floristically diverse savanna in the world. This biome is considered a conservation hotspot in respect to its biodiversity importance and rapid transformation of its landscape. The Cerrado's natural vegetation has been severely transformed by agriculture and pasture activities. Currently it is the main agricultural frontier in Brazil and one of the most threatened Brazilian biomes. This scenario results in environmental impacts such as ecosystems fragmentation as well as losses in connectivity, biodiversity and gene flow, changes in the microclimate and energy, carbon and nutrients cycles, among others. The Priority Areas for Conservation is a governmental program from Brazil that identifies areas with high conservation priority. One of this program's recommendation is a natural vegetation map including their major ecosystem classes. This study aims to generate more precise information for the Cerrado's vegetation. The main objective of this study is to identify which ecosystems are being prioritized and/or threatened by land use, refining information for further protection. In order to test methods, the priority area for conservation Chapada da Contagem was selected as the study site. This area is ranked as "extremely high priority" by the government and is located in the Federal District and Goias State, Brazil. Satellites with finer spatial resolution may improve the classification of the Cerrado's vegetation. Remote sensing methods and two criteria were tested using RapidEye 3A imagery (5m spatial resolution) collected in 2014 in order to classify the Cerrado's major land cover types of this area, as well as its land use. One criterion considers the Cerrado's major terrestrial ecosystems, which are divided into forest, savanna and grassland. The other involves scaling it down to the major physiognomic groups of each ecosystem. Other sources of environmental dataset such

Declining urban and community tree cover in the United States

Science.gov (United States)

David J. Nowak; Eric J. Greenfield

2018-01-01

Paired aerial photographs were interpreted to assess recent changes (c. 2009–2014) in tree, impervious and other cover types within urban/community and urban land in all 50 United States and the District of Columbia. National results indicate that tree cover in urban/community areas of the United States is on the decline at a rate of about 175,000 acres per year, which...

National Level Assessment of Mangrove Forest Cover in Pakistan

Science.gov (United States)

Abbas, S.; Qamer, F. M.; Hussain, N.; Saleem, R.; Nitin, K. T.

2011-09-01

Mangroves ecosystems consist of inter tidal flora and fauna found in the tropical and subtropical regions of the world. Mangroves forest is a collection of halophytic trees, shrubs, and other plants receiving inputs from regular tidal flushing and from freshwater streams and rivers. A global reduction of 25 % mangroves' area has been observed since 1980 and it is categorized as one of to the most threatened and vulnerable ecosystems of the world. Forest resources in Pakistan are being deteriorating both quantitatively and qualitatively due to anthropogenic activities, climatic v and loose institutional management. According to the FAO (2007), extent of forest cover of Pakistan in 2005 is 1,902,000 ha, which is 2.5% of its total land area. Annual change rate during 2000-2005 was -2.1% which is highest among all the countries in Asia. The Indus delta region contains the world's fifth-largest mangrove forest which provides a range of important ecosystem services, including coastal stabilisation, primary production and provision of nursery habitat for marine fish. Given their ecological importance in coastal settings, mangroves receive special attention in the assessment of conservation efforts and sustainable coastal developments. Coastline of Pakistan is 1050km long shared by the provinces, Sind (350km) and Baluchistan (700 km). The coastline, with typical arid subtropical climate, possesses five significant sites that are blessed with mangroves. In the Sindh province, mangroves are found in the Indus Delta and Sandspit. The Indus Delta is host to the most extensive mangroves areas and extends from Korangi Creek in the West to Sir Creek in the East, whereas Sandspit is a small locality in the West of Karachi city. In the Balochistan province, mangroves are located at three sites, Miani Hor, Kalmat Khor and Jiwani. Contemporary methods of Earth observation sciences are being incorporated as an integral part of environmental assessment related studies in coastal areas

Earth observation data for assessment of nationwide land cover and long-term deforestation in Afghanistan

Science.gov (United States)

Sudhakar Reddy, C.; Saranya, K. R. L.

2017-08-01

This study has generated a national level spatial database of land cover and changes in forest cover of Afghanistan for the 1975-1990, 1990-2005 and 2005-2014 periods. Using these results we have analysed the annual deforestation rates, spatial changes in forests, forest types and fragmentation classes over a period of 1975 to 2014 in Afghanistan. The land cover map of 2014 provides distribution of forest (dry evergreen, moist temperate, dry temperate, pine, sub alpine) and non-forest (grassland, scrub, agriculture, wetlands, barren land, snow and settlements) in Afghanistan. The largest land cover, barren land, contributes to 56% of geographical area of country. Forest is distributed mostly in eastern Afghanistan and constitutes an area of 1.02% of geographical area in 2014. The annual deforestation rate in Afghanistan's forests for the period from 1975 to 1990 estimated as 0.06% which was declined significantly from 2005 to 2014. The predominant forest type in Afghanistan is moist temperate which shows loss of 80 km2 of area during the last four decades of the study period. At national level, the percentage of large core forest area was calculated as 52.20% in 2014.

'Stent in a stent'--an alternative technique for removing partially covered stents following sleeve gastrectomy complications.

Science.gov (United States)

Vasilikostas, Georgios; Sanmugalingam, Nimalan; Khan, Omar; Reddy, Marcus; Groves, Chris; Wan, Andrew

2014-03-01

Endoscopic stenting is a relatively new technique for the treatment of post sleeve gastrectomy complications. Partially covered stents are used in this method to minimise the risk of migration but they are associated with difficulties with removal. Patients requiring emergency stenting following sleeve gastrectomy underwent insertion of a partially covered metallic stent. One month later, if the stent was not easily removable, a fully covered overlapping stent was inserted and the patient was readmitted 2 weeks later for removal of both stents. Four patients required stenting following sleeve gastrectomy leaks, and one patient required stenting for a stricture. In these cases, a 'stent in a stent' technique was used for removal. This technique allows the safe removal of partially covered stents inserted following sleeve gastrectomy complications.

Comparison between uncovered and covered self-expandable metal stent placement in malignant duodenal obstruction.

Science.gov (United States)

Kim, Ji Won; Jeong, Ji Bong; Lee, Kook Lae; Kim, Byeong Gwan; Ahn, Dong Won; Lee, Jae Kyung; Kim, Su Hwan

2015-02-07

To compare the clinical outcomes of uncovered and covered self-expandable metal stent placements in patients with malignant duodenal obstruction. A total of 67 patients were retrospectively enrolled from January 2003 to June 2013. All patients had symptomatic obstruction characterized by nausea, vomiting, reduced oral intake, and weight loss. The exclusion criteria included asymptomatic duodenal obstruction, perforation or peritonitis, concomitant small bowel obstruction, or duodenal obstruction caused by benign strictures. The technical and clinical success rate, complication rate, and stent patency were compared according to the placement of uncovered (n = 38) or covered (n = 29) stents. The technical and clinical success rates did not differ between the uncovered and covered stent groups (100% vs 96.6% and 89.5% vs 82.8%). There were no differences in the overall complication rates between the uncovered and covered stent groups (31.6% vs 41.4%). However, stent migration occurred more frequently with covered than uncovered stents [20.7% (6/29) vs 0% (0/38), P stent patency was longer in uncovered than in covered stents [251 d (95%CI: 149.8 d-352.2 d) vs 139 d (95%CI: 45.5 d-232.5 d), P stent (70 d) and covered stent groups (60 d). Uncovered stents may be preferable in malignant duodenal obstruction because of their greater resistance to stent migration and longer stent patency than covered stents.

Regional forest cover estimation via remote sensing: the calibration center concept

Science.gov (United States)

Louis R. Iverson; Elizabeth A. Cook; Robin L. Graham; Robin L. Graham

1994-01-01

A method for combining Landsat Thematic Mapper (TM), Advanced Very High Resolution Radiometer (AVHRR) imagery, and other biogeographic data to estimate forest cover over large regions is applied and evaluated at two locations. In this method, TM data are used to classify a small area (calibration center) into forest/nonforest; the resulting forest cover map is then...

Land-cover mapping using multitemporal, dual-frequency polarimetric SAR data

DEFF Research Database (Denmark)

Skriver, Henning; Schou, Jesper; Dierking, Wolfgang

2000-01-01

during the growing season acquired a lot of data over a Danish agricultural site. The data acquisitions were co-ordinated with ground surveys to obtain a detailed land cover map. The test area contains a large number of different land cover classes, such as more than 10 different crop types, deciduous......The Danish Center for Remote Sensing (DCRS) is, in collaboration with the Danish mapping agency, conducting a study on topographic mapping using SAR data, and land cover mapping results are presented. The Danish EMISAR system (an L- and C-band, fully polarimetric, airborne SAR) have in 1994 to 1999...

Predictive modelling of the spatial pattern of past and future forest cover changes in India

Science.gov (United States)

Reddy, C. Sudhakar; Singh, Sonali; Dadhwal, V. K.; Jha, C. S.; Rao, N. Rama; Diwakar, P. G.

2017-02-01

This study was carried out to simulate the forest cover changes in India using Land Change Modeler. Classified multi-temporal long-term forest cover data was used to generate the forest covers of 1880 and 2025. The spatial data were overlaid with variables such as the proximity to roads, settlements, water bodies, elevation and slope to determine the relationship between forest cover change and explanatory variables. The predicted forest cover in 1880 indicates an area of 10,42,008 km2, which represents 31.7% of the geographical area of India. About 40% of the forest cover in India was lost during the time interval of 1880-2013. Ownership of majority of forest lands by non-governmental agencies and large scale shifting cultivation are responsible for higher deforestation rates in the Northeastern states. The six states of the Northeast (Assam, Manipur, Meghalaya, Mizoram, Nagaland, Tripura) and one union territory (Andaman & Nicobar Islands) had shown an annual gross rate of deforestation of >0.3 from 2005 to 2013 and has been considered in the present study for the prediction of future forest cover in 2025. The modelling results predicted widespread deforestation in Northeast India and in Andaman & Nicobar Islands and hence is likely to affect the remaining forests significantly before 2025. The multi-layer perceptron neural network has predicted the forest cover for the period of 1880 and 2025 with a Kappa statistic of >0.70. The model predicted a further decrease of 2305 km2 of forest area in the Northeast and Andaman & Nicobar Islands by 2025. The majority of the protected areas are successful in the protection of the forest cover in the Northeast due to management practices, with the exception of Manas, Sonai-Rupai, Nameri and Marat Longri. The predicted forest cover scenario for the year 2025 would provide useful inputs for effective resource management and help in biodiversity conservation and for mitigating climate change.

Covered versus uncovered self-expandable metal stents for malignant biliary strictures: A meta-analysis and systematic review.

Science.gov (United States)

Moole, Harsha; Bechtold, Matthew L; Cashman, Micheal; Volmar, Fritz H; Dhillon, Sonu; Forcione, David; Taneja, Deepak; Puli, Srinivas R

2016-09-01

Self-expandable metal stents (SEMS) are used for palliating inoperable malignant biliary strictures. It is unclear if covered metal stents are superior to uncovered metal stents in these patients. We compared clinical outcomes in patients with covered and uncovered stents. Studies using covered and uncovered metallic stents for palliation in patients with malignant biliary stricture were reviewed. Articles were searched in MEDLINE, PubMed, and Ovid journals. Fixed and random effects models were used to calculate the pooled proportions. Initial search identified 1436 reference articles, of which 132 were selected and reviewed. Thirteen studies (n = 2239) for covered and uncovered metallic stents which met the inclusion criteria were included in this analysis. Odds ratio for stent occlusion rates in covered vs. uncovered stents was 0.79 (95 % CI = 0.65 to 0.96). Survival benefit in patients with covered vs. uncovered stents showed the odds ratio to be 1.29 (95 % CI = 0.95 to 1.74). Pooled odds ratio for migration of covered vs. uncovered stents was 9.9 (95 % CI = 4.5 to 22.3). Covered stents seemed to have significantly lesser occlusion rates, increased odds of migration, and increased odds of pancreatitis compared to uncovered stents. There was no statistically significant difference in the survival benefit, overall adverse event rate, and patency period of covered vs. uncovered metal stents in patients with malignant biliary strictures.

Transjugular Intrahepatic Portosystemic Shunts in Patients with Cirrhosis with Refractory Ascites: Comparison of Clinical Outcomes by Using 8- and 10-mm PTFE-covered Stents.

Science.gov (United States)

Miraglia, Roberto; Maruzzelli, Luigi; Tuzzolino, Fabio; Petridis, Ioannis; D'Amico, Mario; Luca, Angelo

2017-07-01

Purpose To compare the efficacy and complications of transjugular intrahepatic portosystemic shunt (TIPS) creation performed by using a 10-mm or an 8-mm-diameter polytetrafluoroethylene (PTFE)-covered stent in a consecutive series of patients with cirrhosis with refractory ascites (RA). Materials and Methods The institutional review board approved this retrospective study and informed consent was waived. One hundred seventy-one patients with RA (mean age, 58.7 years ± 10.3; 95% confidence interval [CI]: 57.2 years, 60.3 years) had undergone TIPS placement by using 10-mm (60 patients) or 8-mm (111 patients) covered stent between January 2004 and December 2012. Median follow-up time was 16.8 months (range, 3.4-84.8 months). Hemodynamic changes, incidence of hepatic encephalopathy, and long-term (>3 months) need for paracentesis after TIPS placement were evaluated and calculated by using the Kaplan-Meier method and were compared by using the log-rank test. Results Pre-TIPS demographics and clinical characteristics of the two groups were comparable. The portosystemic gradient before TIPS was 17.0 mm Hg ± 4.2 (95% CI: 15.9 mm Hg, 18.1 mm Hg) in the 10-mm group versus 16.1 mm Hg ± 3.7 (95% CI: 15.4 mm Hg, 16.8 mm Hg) in the 8-mm group (P = .164). After TIPS, the portosystemic gradient was 6.5 mm Hg ± 3.4 (95% CI: 5.7 mm Hg, 7.4 mm Hg) in the 10-mm group versus 7.5 mm Hg ± 2.6 (95% CI: 6.9 mm Hg, 7.9 mm Hg) in the 8-mm group (P = .039). The long-term need for paracentesis was greater in the 8-mm group (64 of 111 patients [58%] vs 18 of 60 patients [31%], P = .003). Overall, hepatic encephalopathy was similar in both groups (45 of 111 patients [41%] vs 26 of 60 patients [44%], P = .728). Conclusion A10-mm PTFE-covered stent leads to better control of RA secondary to portal hypertension in patients with cirrhosis, compared with an 8-mm stent, without increasing the incidence of hepatic encephalopathy. © RSNA, 2017.

Polyorethaoe-covered nitinol strecker stents as primary palliative treatment of malignant biliary obstruction

International Nuclear Information System (INIS)

Kanasaki, Shuzo; Furukawa, Akira; Kane, Teruyuki; Murata, Kiyoshi

2000-01-01

Purpose: To evaluate the clinical efficacy of the polyure-thane-covered Nitinol Strecker stent in the treatment of patients with malignant biliary obstruction.Methods: Twenty-three covered stents produced by us were placed in 18 patients with malignant biliary obstruction. Jaundice was caused by cholangiocarcinoma (n=5), pancreatic Cancer (n=6), gallbladder Cancer (n=4), metastatic lymph nodes (n=2), and tumor of the papilla (n=1).Resulrs: The mean patency period of the Stents was 37.5 weeks (5-106 weeks). Recurrent obstructive jaundice occurred in two patients (11%). Adequate biliary drainage over 50 weeks or until death was achieved in 17 of 18 patients (94.4%). Late cholangitis was observed in two patients whose stents bridged the ampulla of Vater. Other late severe complications were not encountered.Conclusion: Although more study is necessary, our results suggest the clinical efficacy of our covered Nitinol Strecker stent in the management of obstructive jaundice caused by malignant diseases.

Soybean growth and yield under cover crops

Directory of Open Access Journals (Sweden)

Priscila de Oliveira

2013-04-01

Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

Multidimensional simulation of radon diffusion through earthen covers

International Nuclear Information System (INIS)

Mayer, D.W.; Gee, G.W.

1983-01-01

The purpose of this report is to document applications of the RADMD model used at PNL to perform analyses of radon diffusion through uranium mill tailings cover systems. The accuracy of the numerical formulation of the RADMD model was demonstrated through a comparison with a two-dimensional analytic solution to the radon diffusion equation. Excellent agreement was obtained between two-dimensional radon concentration profiles predicted by RADMD and those obtained with the analytic solution. A simulation was made of radon diffusion into a test canister using the two dimensional capabilities of RADMD. The radon flux profile was computed and illustrates the effects of the canister on the surface radon flux. The influence of the canister on the radon flux was shown to be significant under certain circumstances. Defects in earthen cover systems were evaluated using the three dimensional capabilities of RADMD. The results support the expectation that defective covers can increase the surface flux from a covered talings pile. Compared to a cover with no defects, radon flux could be elevated by as much as a factor of three when 20% of the radon control layer area contained pockets of reduced moisture. The effects of temporal and spatial variations in moisture content have been modeled by coupling RADMD with a variable saturated flow model. Two dimensional simulations were made of the time dependence of radon flux from a tailings site before and after cover placement. The results demonstrated the expected flux reduction produced by a thick earthen cover. Time dependence of the radon flux after cover placement was attributed to slight changes in moisture content of the cover material with time. The particular cover studied had a compacted clay layer that effectively attenuated the radon

Normalized difference vegetation index (ndvi) analysis for land cover types using landsat 8 oli in besitang watershed, Indonesia

Science.gov (United States)

Zaitunah, A.; Samsuri; Ahmad, A. G.; Safitri, R. A.

2018-03-01

Watershed is an ecosystem area confined by topography and has function as a catcher, storage, and supplier of water, sediments, pollutants and nutrients in the river system and exit through a single outlet. Various activities around watershed areas of Besitang have changed the land cover and vegetation index (NDVI) that exist in the region. In order to detect changes in land cover and NDVI quickly and accurately, we used remote sensing technology and geographic information systems (GIS). The study aimed to assess changes in land cover and vegetation density (NDVI) between 2005 and 2015, as well as obtaining the density of vegetation (NDVI) on each of the land cover of 2005 and 2015. The research showed the extensive of forest area of 949.65 Ha and a decline of mangrove forest area covering an area of 2,884.06 Ha. The highest vegetation density reduced 39,714.58 Ha, and rather dense increased 24,410.72 Ha between 2005 and 2015. The land cover that have the highest NDVI value range with very dense vegetation density class is the primary dry forest (0.804 to 0.876), followed by secondary dry forest (0.737 to 0.804) for 2015. In 2015 the land cover has NDVI value range the primary dry forest (0.513 to 0.57), then secondary dry forest (0.456 to 0.513) with dense vegetation density class

DMSA scan nomograms for renal length and area: Related to patient age and to body weight, height or surface area

International Nuclear Information System (INIS)

Hassan, I.M.; Que, L.; Rutland, M.D.

2002-01-01

Aim: To create nomograms for renal size as measured from DMSA renal studies, and to test the nomograms for their ability to separate normal from abnormal kidneys. Method: Renal length was measured from posterior oblique views and renal area from posterior views. Results from 253 patients with bilateral normal kidneys were used to create nomograms for renal size relative to patient age, body height, weight or body surface area (BSA). The nomograms enclosed 95% of the normal kidneys, thus indicating the range for 95% confidence limits, and hence the specificity. Each nomogram was then tested against 46 hypertrophied kidneys and 46 damaged kidneys. Results: The results from nomograms of renal length and renal area, compared to age, body height, body weight and BSA are presented. For each nomogram, the range is presented as a fraction of the mean value, and the number of abnormal kidneys (hypertrophied or damaged) outside the normal range is presented as a percentage (indicating the sensitivity). Conclusion: Renal Area was no better than renal length for detecting abnormal kidneys. Patient age was the least useful method of normalisation. BSA normalisation produced the best results most frequently (narrower ranges and highest detection of abnormal kidneys)

National Land Cover Database (NLCD) Land Cover Collection

Data.gov (United States)

U.S. Geological Survey, Department of the Interior — The National Land Cover Database (NLCD) Land Cover Collection is produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC)...

Ash and sludge covering of mine waste. Benefits and/or risks using ash and sludge for covering of mine waste; Askor och roetslam som taeckskikt foer gruvavfall. Foerdelar och/eller risker med att anvaenda aska och slam som taeckskikt foer gruvavfall

Energy Technology Data Exchange (ETDEWEB)

Baeckstroem, Mattias; Johansson, Inger [Oerebro Univ. (Sweden). Man-Technology-Environment Research Centre

2004-01-01

One of the main sources for metal pollution in Sweden is mine waste. One way to decrease the leaching of metals from mine waste areas is covering which decreases the formation of acid drainage. There is a shortage of appropriate materials to use for covering, and excavation of till and clay from the environment might cause damages on the landscape. Previous studies have demonstrated that sludge and ashes are suitable materials for covering of waste deposits. When covering mine waste with ash and sludge various positive effects would arise, since the production of drainage water decreases as well as the pH increases due to the high buffer-capacity of the ash. In Ervalla outside Oerebro an area with mine waste has been covered with ash and sludge. This area gives a unique possibility to study benefits and/or risks with the covering of mine waste with ash and sludge. This report is a summary of the first phase of the project and the focus has been on characterisation of the material that has been used for covering. Also a monitoring program for the area has started. Preliminary findings indicate that that the covering decreases the leaching of some metals whereas the leaching of some metals increases. A decrease in the concentration of iron, nickel, cobalt and lead was observed and an increase was observed for arsenic, barium, chromium and copper.

Diel hysteresis between soil respiration and soil temperature in a biological soil crust covered desert ecosystem.

Science.gov (United States)

Guan, Chao; Li, Xinrong; Zhang, Peng; Chen, Yongle

2018-01-01

Soil respiration induced by biological soil crusts (BSCs) is an important process in the carbon (C) cycle in arid and semi-arid ecosystems, where vascular plants are restricted by the harsh environment, particularly the limited soil moisture. However, the interaction between temperature and soil respiration remains uncertain because of the number of factors that control soil respiration, including temperature and soil moisture, especially in BSC-dominated areas. In this study, the soil respiration in moss-dominated crusts and lichen-dominated crusts was continuously measured using an automated soil respiration system over a one-year period from November 2015 to October 2016 in the Shapotou region of the Tengger Desert, northern China. The results indicated that over daily cycles, the half-hourly soil respiration rates in both types of BSC-covered areas were commonly related to the soil temperature. The observed diel hysteresis between the half-hourly soil respiration rates and soil temperature in the BSC-covered areas was limited by nonlinearity loops with semielliptical shapes, and soil temperature often peaked later than the half-hourly soil respiration rates in the BSC-covered areas. The average lag times between the half-hourly soil respiration rates and soil temperature for both types of BSC-covered areas were two hours over the diel cycles, and they were negatively and linearly related to the volumetric soil water content. Our results highlight the diel hysteresis phenomenon that occurs between soil respiration rates and soil temperatures in BSC-covered areas and the negative response of this phenomenon to soil moisture, which may influence total C budget evaluations. Therefore, the interactive effects of soil temperature and moisture on soil respiration in BSC-covered areas should be considered in global carbon cycle models of desert ecosystems.

Spatiotemporal Change Detection in Forest Cover Dynamics Along Landslide Susceptible Region of Karakoram Highway, Pakistan

Science.gov (United States)

Rashid, Barira; Iqbal, Javed

2018-04-01

Forest Cover dynamics and its understanding is essential for a country's social, environmental, and political engagements. This research provides a methodical approach for the assessment of forest cover along Karakoram Highway. It has great ecological and economic significance because it's a part of China-Pakistan Economic Corridor. Landsat 4, 5 TM, Landsat 7 ETM and Landsat 8 OLI imagery for the years 1990, 2000, 2010 and 2016 respectively were subjected to supervised classification in ArcMap 10.5 to identify forest change. The study area was categorized into five major land use land cover classes i.e., Forest, vegetation, urban, open land and snow cover. Results from post classification forest cover change maps illustrated notable decrease of almost 26 % forest cover over the time period of 26 years. The accuracy assessment revealed the kappa coefficients 083, 0.78, 0.77 and 0.85, respectively. Major reason for this change is an observed replacement of native forest cover with urban areas (12.5 %) and vegetation (18.6 %) However, there is no significant change in the reserved forests along the study area that contributes only 2.97 % of the total forest cover. The extensive forest degradation and risk prone topography of the region has increased the environmental risk of landslides. Hence, effective policies and forest management is needed to protect not only the environmental and aesthetic benefits of the forest cover but also to manage the disaster risks. Apart from the forest assessment, this research gives an insight of land cover dynamics, along with causes and consequences, thereby showing the forest degradation hotspots.

COVERS Neonatal Pain Scale: Development and Validation

Directory of Open Access Journals (Sweden)

Ivan L. Hand

2010-01-01

Full Text Available Newborns and infants are often exposed to painful procedures during hospitalization. Several different scales have been validated to assess pain in specific populations of pediatric patients, but no single scale can easily and accurately assess pain in all newborns and infants regardless of gestational age and disease state. A new pain scale was developed, the COVERS scale, which incorporates 6 physiological and behavioral measures for scoring. Newborns admitted to the Neonatal Intensive Care Unit or Well Baby Nursery were evaluated for pain/discomfort during two procedures, a heel prick and a diaper change. Pain was assessed using indicators from three previously established scales (CRIES, the Premature Infant Pain Profile, and the Neonatal Infant Pain Scale, as well as the COVERS Scale, depending upon gestational age. Premature infant testing resulted in similar pain assessments using the COVERS and PIPP scales with an r=0.84. For the full-term infants, the COVERS scale and NIPS scale resulted in similar pain assessments with an r=0.95. The COVERS scale is a valid pain scale that can be used in the clinical setting to assess pain in newborns and infants and is universally applicable to all neonates, regardless of their age or physiological state.

The role of rabbit density and the diversity of weeds in the development of cover crops in olive groves

Energy Technology Data Exchange (ETDEWEB)

Guerrero-Casado, J.; Carpio, A.J.; Prada, L.M.; Tortosa, F.S.

2015-07-01

Cover crops are an effective means to reduce soil erosion and to provide food and shelter for wildlife. However, in areas of intensive farming, which are characterised by the scarcity of weed communities, wild herbivores may focus their grazing on cover crops, which could make their implementation difficult. In this work, we test whether rabbit grazing can prevent the growth of herbaceous cover crops in olive groves in Southern Spain in addition to assessing the role of rabbit abundance and diversity of weeds in the development of cover crops. This question has been addressed by sowing Bromus rubens between the rows of five olive groves in Cordoba province (Spain). We then monitored the surface covered by B. rubens, along with both diversity of weed communities and rabbit abundance. Two rabbit exclusion areas were also placed in each olive grove in order to assess the impact of rabbits on the development of cover crops. Our results showed that the surface occupied by B. rubens was considerably higher in the rabbit exclusion areas (mean 56.8 ± 5.65 %) than in those areas in which they could feed (mean 35.6 ± 4.32 %). The coverage occupied by cover crops was higher in areas with lower rabbit density, although this relationship was modulated by the weed diversity index, since in areas with the same rabbit abundance the coverage was higher in those with a richer weed community. These findings suggest that high rabbit abundances can prevent the development of herbaceous cover crops in olive groves, particularly in areas in which alternative food resources (measured as weed diversity) are scarce. (Author)

The role of rabbit density and the diversity of weeds in the development of cover crops in olive groves

Directory of Open Access Journals (Sweden)

José Guerrero-Casado

2015-09-01

Full Text Available Cover crops are an effective means to reduce soil erosion and to provide food and shelter for wildlife. However, in areas of intensive farming, which are characterised by the scarcity of weed communities, wild herbivores may focus their grazing on cover crops, which could make their implementation difficult. In this work, we test whether rabbit grazing can prevent the growth of herbaceous cover crops in olive groves in Southern Spain in addition to assessing the role of rabbit abundance and diversity of weeds in the development of cover crops. This question has been addressed by sowing Bromus rubens between the rows of five olive groves in Cordoba province (Spain. We then monitored the surface covered by B. rubens, along with both diversity of weed communities and rabbit abundance. Two rabbit exclusion areas were also placed in each olive grove in order to assess the impact of rabbits on the development of cover crops. Our results showed that the surface occupied by B. rubens was considerably higher in the rabbit exclusion areas (mean 56.8 ± 5.65 % than in those areas in which they could feed (mean 35.6 ± 4.32 %. The coverage occupied by cover crops was higher in areas with lower rabbit density, although this relationship was modulated by the weed diversity index, since in areas with the same rabbit abundance the coverage was higher in those with a richer weed community. These findings suggest that high rabbit abundances can prevent the development of herbaceous cover crops in olive groves, particularly in areas in which alternative food resources (measured as weed diversity are scarce.

Engineered soil covers for management of salt impacted sites

International Nuclear Information System (INIS)

Sweeney, D.A.; Tratch, D.J.

2005-01-01

The use of engineered soil cover systems to mitigate environmental impacts from tailings and waste rock piles is becoming an accepted practice. This paper presented design concepts for soil covers related to reclamation practices in the mining industry as an effective risk management practice at salt impacted sites. Research and field programs have demonstrated that a layered engineered soil cover can reduce or eliminate infiltration. Key components of the system included re-establishing surface vegetation to balance precipitation fluxes with evapotranspiration potential, and design of a capillary break below the rooting zone to minimize deeper seated infiltration. It was anticipated that the incorporation of a vegetation cover and a capillary break would minimize infiltration into the waste rock or tailing pile and reduce the generation of acid rock drainage (ARD). Design of a layered soil cover requires the incorporation of meteorological data, moisture retention characteristics of the impacted soils, and proposed engineered cover materials. Performance of the soil cover was predicted using a finite element model combined with meteorological data from the site area, unsaturated soil properties of the parent sub-surface soils and potential covered materials. The soil cover design consisted of re-vegetation and a loose clay cover overlying a compacted till layer. The design was conducted for an off site release of salt impacted pasture land adjacent to a former highway maintenance yard. The model predicted minimal infiltration during high precipitation events and no infiltration during low precipitation events. Results indicated that the proposed soil cover would enable re-establishment of a productive agricultural ground cover, as well as minimizing the potential for additional salt migration. It was concluded that further research and development is needed to ensure that the cover system is an acceptable method for long-term risk management. 17 refs., 5 figs

Interfacial stability of soil covers on lined surface impoundments

International Nuclear Information System (INIS)

Mitchell, D.H.; Gates, T.E.

1986-04-01

The factors affecting the interfacial stability of soil covers on geomembranes were examined to determine the maximum stable slopes for soil cover/geomembrane systems. Several instances of instability of soil covers on geomembranes have occurred at tailings ponds, leaving exposed geomembranes with the potential for physical ddamage and possibly chemical and ultraviolet degradation. From an operator's viewpoint, it is desirable to maximize the slope of lined facilities in order to maximize the volume-to-area ratio; however, the likelihood for instability also increases with increasing slope. Frictional data obtained from direct shear tests are compared with stability data obtained using a nine-square-meter (m 2 ) engineering-scale test stand to verify that direct shear test data are valid in slope design calculations. Interfacial frictional data from direct shear tests using high-density polyethylene and a poorly graded sand cover agree within several degrees with the engineering-scale tests. Additional tests with other soils and geomembranes are planned. The instability of soil covers is not always an interfacial problem; soil erosion and limited drainage capacity are additional factors that must be considered in the design of covered slopes. 7 refs., 5 figs., 2 tabs

Multitemporal analysis of the change of earth covering; high basin Guatiquia River - Low Sector

International Nuclear Information System (INIS)

Prieto Gonzalez, Jose Luis

1999-01-01

One of the basic functions inside the environmental administration has been the record of the variables of the natural environment. The earth covering corresponds to one of the elements that to the registered being and analyzed, shows with more fidelity the evolution of the environment. At the present time, and from their creation in 1992, the project Guatiquia River - PRG that covers 90.000 approximately has. Located between the Cundinamarca and Meta Departments, it has looked for to obtain the necessary technical elements to achieve a sustainable handling in the area, for it, it intended to be ahead a study that allows to quantify and to analyze the changes of the earth covering, reason for which, it was ahead the present study: multitemporal analysis of the change of earth covering high basin of the Guatiquia River low sector, for a total surface of 13997.64 hectares (corresponding to 15.8% of the area of action of the Project Guatiquia River), and having as basic tools the remote perception and the geographical information systems, it was carried out the prosecution of the information of earth covering in the study area for the years 1993 and 1997 starting from which, were determined and analyzed the changes of earth covering, they were presented in cartographic documents to scale 1:25.000, corresponding to a detailed study

The role of protected areas in land use/land cover change and the carbon cycle in the conterminous United States

Energy Technology Data Exchange (ETDEWEB)

Lu, Xiaoliang [The Ecosystems Center, Marine Biological Laboratory, Woods Hole MA USA; Zhou, Yuyu [Departments of Geological and Atmospheric Sciences, Iowa State University, Ames IA USA; Liu, Yaling [Pacific Northwest National Laboratory, Joint Global Change Research Institute, College Park MD USA; Le Page, Yannick [Department Tapada da Ajuda, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon Portugal

2017-08-08

Protected areas (PAs) cover about 22% of the conterminous United States. Understanding their role on historical land use and land cover change (LULCC) and on the carbon cycle is essential to provide guidance for environmental policies. In this study, we compiled historical LULCC and PAs data to explore these interactions within the terrestrial ecosystem model (TEM). We found that intensive LULCC occurred in the conterminous United States from 1700 to 2005. More than 3 million km2 of forest, grassland and shrublands were converted into agricultural lands, which caused 10,607 Tg C release from land ecosystems to atmosphere. PAs had experienced little LULCC as they were generally established in the 20th century after most of the agricultural expansion had occurred. PAs initially acted as a carbon source due to land use legacies, but their accumulated carbon budget switched to a carbon sink in the 1960s, sequestering an estimated 1,642 Tg C over 1700–2005, or 13.4% of carbon losses in non-PAs. We also find that PAs maintain larger carbon stocks and continue sequestering carbon in recent years (2001–2005), but at a lower rate due to increased heterotrophic respiration as well as lower productivity associated to aging ecosystems. It is essential to continue efforts to maintain resilient, biodiverse ecosystems and avoid large-scale disturbances that would release large amounts of carbon in PAs.

Evaluation of vegetation cover using the normalized difference vegetation index (NDVI

Directory of Open Access Journals (Sweden)

Gabriela Camargos Lima

2013-08-01

Full Text Available Soil loss by water erosion is the main cause of soil degradation in Brazil. However, erosion can be reduced by the presence of vegetation. The Normalized Difference Vegetation Index (NDVI makes it possible to identify the vegetative vigor of crops or natural vegetation which facilities the identification of areas with vegetation covers. This information is very important in identifying the phenomena which might be occurring in a particular area, especially those related to soil degradation by water erosion. Thus, the aim of this work was to assess the canopy cover by using NDVI, checking the image accuracy using the Coverage Index (CI based on the Stocking method, in the Sub-basin of Posses, which belongs to the Cantareira System, located in the Extrema municipality, Minas Gerais, Brazil. Landsat-5 TM images were used. The sub-basin of Posses was very altered in comparison to the surrounding areas. The NDVI technique proved to be a suitable tool to assess the uses that occur in the sub-basin of Posses, as validated by the Stocking methodology. The map derived from NDVI allowed the geographic distribution of different land uses to be observed and allowed for the identification of critical areas in relation to vegetation cover as well. This finding can be used to optimize efforts to recover and protect soil in areas with bare soil and degraded pasture, in order to reduce environmental degradation. The CI has not exceeded 40% for land use classes that occur in the majority of the sub-basin (91%, except in areas of woody vegetation.

Malignant duodenal obstructions: palliative treatment with covered expandable nitinol stent

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Chul; Jung, Gyoo Sik; Lee, Sang Hee; Kim, Sung Min; Oh, Kyung Seung; Huh, Jin Do; Cho, Young Duk [College of Medicine, Kosin Univ, Pusan (Korea, Republic of); Song, Ho Young [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of)

2002-04-01

To evaluate the feasibility and clinical effectiveness of using a polyurethane-covered expandable nitinol stent in the palliative treatment of malignant duodenal obstruction. Under fluoroscopic guidance, a polyurethane-covered expandable nitinol stent was placed in 12 consecutive patients with malignant duodenal obstructions. All presented with severe nausea and recurrent vomiting. The underlying causes of obstruction were duodenal carcinoma (n=4), pancreatic carcinoma (n=4), gall bladder carcinoma (n=2), distal CBD carcinoma (n=1), and uterine cervical carcinoma (n=1). The sites of obstruction were part I (n=1), part II (n=8), and III (n=3). Due to pre-existing jaundice, eight patients with part II obstructions underwent biliary decompression prior to stent placement. An introducer sheath with a 6-mm outer diameter and stents 16 mm in diameter were employed, and to place the stent, and after-loading technique was used. Stent placement was technically successful in ten patients, and no procedural complications occuured. In one of two patients in whom there was technical failure, and in whom the obstructions were located in part III, the stent was placed transgastrically. Stent migration occurred in one patient four days after the procedure, and treatment involved the palcement of a second, uncovered, nitinol stent. After stent placement, symptoms improved in all patients. During follow-up, obstructive symptoms due to stent stenosis (n=1), colonic obstruction (n=1), and multiple small bowel obstruction (n=1) recurred in three patients. Two of these were treated by placing additional stents in the duodenum and colon, respectively. One of the eight patients in whom a stent was placed in the second portion of the duodenum developed jaundice. The patients died a mean 14 (median, 9) weeks after stent placement. The placement of a polyurethane-covered expandable nitinol stent seems to be technically feasible, safe and effective for the palliative treatment of malignant

[Effects of land cover change on soil organic carbon and light fraction organic carbon at river banks of Fuzhou urban area].

Science.gov (United States)

Zeng, Hong-Da; Du, Zi-Xian; Yang, Yu-Sheng; Li, Xi-Bo; Zhang, Ya-Chun; Yang, Zhi-Feng

2010-03-01

By using Vario EL III element analyzer, the vertical distribution characteristics of soil organic carbon (SOC) and light-fraction organic carbon (LFOC) in the lawn, patch plantation, and reed wetland at river banks of Fuzhou urban area were studied in July 2007. For all the three land cover types, the SOC and LFOC contents were the highest in surface soil layer, and declined gradually with soil depth. Compared with reed wetland, the lawn and patch plantation had higher SOC and LFOC contents in each layer of the soil profile (0-60 cm), and the lawn had significantly higher contents of SOC and LFOC in 0-20 cm soil layer, compared with the patch plantation. After the reed wetland was converted into lawn and patch plantation, the SOC stock in the soil profile was increased by 94.8% and 72.0%, and the LFOC stock was increased by 225% and 93%, respectively. Due to the changes of plant species, plant density, and management measure, the conversion from natural wetland into human-manipulated green spaces increased the SOC and LFOC stocks in the soil profile, and improved the soil quality. Compared with the SOC, soil LFOC was more sensitive to land use/cover change, especially for those in 0-20 cm soil layer.

Examining Land Cover and Greenness Dynamics in Hangzhou Bay in 1985–2016 Using Landsat Time-Series Data

Directory of Open Access Journals (Sweden)

Dengqiu Li

2017-12-01

Full Text Available Land cover changes significantly influence vegetation greenness in different regions. Dense Landsat time series stacks provide unique opportunity to analyze land cover change and vegetation greenness trends at finer spatial scale. In the past three decades, large reclamation activities have greatly changed land cover and vegetation growth of coastal areas. However, rarely has research investigated these frequently changed coastal areas. In this study, Landsat Normalized Difference Vegetation Index time series (1984–2016 data and the Breaks For Additive Seasonal and Trend algorithm were used to detect the intensity and dates of abrupt changes in a typical coastal area—Hangzhou Bay, China. The prior and posterior land cover categories of each change were classified using phenology information through a Random Forest model. The impacts of land cover change on vegetation greenness trends of the inland and reclaimed areas were analyzed through distinguishing gradual and abrupt changes. The results showed that the intensity and date of land cover change were detected successfully with overall accuracies of 88.7% and 86.1%, respectively. The continuous land cover dynamics were retrieved accurately with an overall accuracy of 91.0% for ten land cover classifications. Coastal reclamation did not alleviate local cropland occupation, but prompted the vegetation greenness of the reclaimed area. Most of the inland area showed a browning trend. The main contributors to the greenness and browning trends were also quantified. These findings will help the natural resource management community generate better understanding of coastal reclamation and make better management decisions.

Anthropogenic Influences in Land Use/Land Cover Changes in Mediterranean Forest Landscapes in Sicily

Directory of Open Access Journals (Sweden)

Donato S. La Mela Veca

2016-01-01

Full Text Available This paper analyzes and quantifies the land use/land cover changes of the main forest and semi-natural landscape types in Sicily between 1955 and 2012. We analyzed seven representative forest and shrubland landscapes in Sicily. These study areas were chosen for their importance in the Sicilian forest panorama. We carried out a diachronic survey on historical and current aerial photos; all the aerial images used to survey the land use/land cover changes were digitalized and georeferenced in the UTM WGS84 system. In order to classify land use, the Regional Forest Inventory 2010 legend was adopted for the more recent images, and the CORINE Land Cover III level used for the older, lower resolution images. This study quantifies forest landscape dynamics; our results show for almost all study areas an increase of forest cover and expansion, whereas a regressive dynamic is found in rural areas due to intensive agricultural and pasturage uses. Understanding the dynamics of forest landscapes could enhance the role of forestry policy as a tool for landscape management and regional planning.

Minimum triplet covers of binary phylogenetic X-trees.

Science.gov (United States)

Huber, K T; Moulton, V; Steel, M

2017-12-01

Trees with labelled leaves and with all other vertices of degree three play an important role in systematic biology and other areas of classification. A classical combinatorial result ensures that such trees can be uniquely reconstructed from the distances between the leaves (when the edges are given any strictly positive lengths). Moreover, a linear number of these pairwise distance values suffices to determine both the tree and its edge lengths. A natural set of pairs of leaves is provided by any 'triplet cover' of the tree (based on the fact that each non-leaf vertex is the median vertex of three leaves). In this paper we describe a number of new results concerning triplet covers of minimum size. In particular, we characterize such covers in terms of an associated graph being a 2-tree. Also, we show that minimum triplet covers are 'shellable' and thereby provide a set of pairs for which the inter-leaf distance values will uniquely determine the underlying tree and its associated branch lengths.

Sustaining forest landscape connectivity under different land cover change scenarios

Energy Technology Data Exchange (ETDEWEB)

Rubio, L.; Rodriguez-Freire, M.; Mateo-Sanchez, M. C.; Estreguil, C.; Saura, S.

2012-11-01

Managing forest landscapes to sustain functional connectivity is considered one of the key strategies to counteract the negative effects of climate and human-induced changes in forest species pools. With this objective, we evaluated whether a robust network of forest connecting elements can be identified so that it remains efficient when facing different types of potential land cover changes that may affect forest habitat networks and ecological fluxes. For this purpose we considered changes both in the forested areas and in the non-forest intervening landscape matrix. We combined some of the most recent developments in graph theory with models of land cover permeability and least-cost analysis through the forest landscape. We focused on a case of study covering the habitat of a forest dwelling bird (nuthatch, Sitta europaea) in the region of Galicia (NW Spain). Seven land-use change scenarios were analysed for their effects on connecting forest elements (patches and links): one was the simplest case in which the landscape is represented as a binary forest/non-forest pattern (and where matrix heterogeneity is disregarded), four scenarios in which forest lands were converted to other cover types (to scrubland due to wildfires, to extensive and intensive agriculture, and to urban areas), and two scenarios that only involved changes in the non-forested matrix (re naturalization and intensification). Our results show that while the network of connecting elements for the species was very robust to the conversion of the forest habitat patches to different cover types, the different change scenarios in the landscape matrix could more significantly weaken its long-term validity and effectiveness. This is particularly the case when most of the key connectivity providers for the nuthatch are located outside the protected areas or public forests in Galicia, where biodiversity-friendly measures might be more easily implemented. We discuss how the methodology can be applied to

DMBLC: An Indirect Urban Impervious Surface Area Extraction Approach by Detecting and Masking Background Land Cover on Google Earth Image

Directory of Open Access Journals (Sweden)

Min Huang

2018-05-01

Full Text Available Implying the prosperity and development of the city, impervious surface area (ISA is playing an increasingly important role in ecological processes, microclimate, material and energy flows, and urban flood. The free sub-meter resolution Google Earth image, which is integrated by several high spatial resolution data, appears to have potential for high-resolution ISA extraction, where present study is rare and performances remain to be improved. Due to the high spatial and spectral variation of the urban environment as well as confusion between ISA and soil, the accurate delineating of ISA with traditional (direct methods can be costly and time-consuming, which is in a word resource-intensive. However, this paper presents a novel indirect ISA extraction conceptual model and a new detecting and masking background land cover (DMBLC approach that: uses a freely available, high-resolution dataset; requires a reduced set of training samples; and consists of relatively simple, common, and feasible image processing steps. The key characteristic of DMBLC is to detect the background of ISA (vegetation, soil, and water accurately and obtain the ISA by masking the background. The approach relies on background detection to avoid the predicaments of direct ISA extraction. Water can be directly gained by water body vector data, in DMBLC; mixture tuned matched filtering (MTMF is exploited to detect vegetation and soil, image segmentation is used to mitigate the spectral variation problem within the same land cover, and segment rectangularity reduces the confusion between ISA and soil. From experiments in a core area of Fuzhou, China, the DMBLC approach reached high performance and outperformed the powerful traditional support vector machines (SVM method (overall accuracy of 94.45% and Kappa coefficient of 0.8885, compared to 86.44% and 0.7329, respectively. From the comparison of different levels of complexity within the inner processing steps, it is confirmed

Status of vegetation cover after 25 years since the last wildfire (Río Verde, Spain)

Science.gov (United States)

Martinez-Murillo, Juan F.; Remond, Ricardo; Ruiz-Sinoga, José D.

2016-04-01

Climatic conditions play an important role in the post-fire vegetation recovery as well as other factors like topography, soil, and pre and post-fire land use (Shakesby, 2011; Robichaud et al., 2013). This study deals with the characterization of the vegetation cover status in an area affected by a wildfire 25 years ago. Namely, the objectives are to: i) compare the current and previous vegetation cover to wildfire; and ii) evaluate whether the current vegetation has recovered the previous cover to wildfire. The study area is mainly located in the Rio Verde watershed (Sierra de las Nieves, South of Spain). It corresponds to an area affected by a wildfire in August 8th, 1991. The burned area was equal to 8,156 ha. The burn severity was spatially very high. The main geographic features of the burned area are: mountainous topography (altitudes ranging from 250 m to 1700 m; slope gradient >25%; exposure mainly southfacing); igneous (peridotites), metamorphic (gneiss) and calcareous rocks (limestones); and predominant forest land use (Pinus pinaster sp. woodlands, 10%; pinus opened forest + shrubland, 40%; shrubland, 35%; and bare soil + grassland, 15%). Remote sensing techniques and GIS analysis has been applied to achieve the objectives. Landsat 5 and Landsat 8 images were used: July 13th, 1991 and July 1st, 2013, for the previous wildfire situation and 22-years after, respectively. The 1990 CORINE land cover was also considered to map 1991 land uses prior the wildfire. The Andalucía Regional Government wildfire historic records were used to select the burned area and its geographical limit. 1991 and 2013 land cover maps were obtained by means of object-oriented classifications. Also, NDVI index were calculated and mapped for both years in order to compare the status of vegetation cover. According to the results, the combination of remote sensing and GIS analysis let map the most recovered areas affected by the wildfire in 1991. The vegetation indexes indicated that

Palliation of Postoperative Gastrointestinal Anastomotic Malignant Strictures with Flexible Covered Metallic Stents: Preliminary Results

International Nuclear Information System (INIS)

Lee, Jeong-Min; Han, Young Min; Lee, Sang Yong; Kim, Chong Soo; Yang, Doo Hyun; Lee, Seung Ok

2001-01-01

Purpose: To evaluate the efficacy of the placement of covered metallic stents for palliation of gastrointestinal anastomotic strictures secondary to recurrent gastric cancer.Methods: Under fluoroscopic guidance, placement of one or two self-expandable covered metallic stents was attempted perorally in 11 patents (aged 48-76 years) with anastomotic stenoses due to recurrent gastric malignancies. The strictures involved both the afferent and efferent loops in three patients. All patients had poor peroral food intake with severe nausea and vomiting after ingestion. The technical and clinical success was evaluated.Results: Placement of the covered stent was technically successful in 13 of 15 (87%) attempts in ten patients. After the procedure, 9 of 11 (82%) patients overall were able to ingest at least a liquid diet and had markedly decreased incidence of vomiting. During the follow-up of 2-31 weeks (mean 8.5 weeks) there were no major complications.Conclusion: These preliminary results suggest that flexible, covered stents may provide effective palliation of malignant anastomotic stricture secondary to recurrent gastric cancer

Deriving Snow Cover Metrics for Alaska from MODIS

Directory of Open Access Journals (Sweden)

Chuck Lindsay

2015-09-01

Full Text Available Moderate Resolution Imaging Spectroradiometer (MODIS daily snow cover products provide an opportunity for determining snow onset and melt dates across broad geographic regions; however, cloud cover and polar darkness are limiting factors at higher latitudes. This study presents snow onset and melt dates for Alaska, portions of western Canada and the Russian Far East derived from Terra MODIS snow cover daily 500 m grid data (MOD10A1 and evaluates our method for filling data gaps caused by clouds or polar darkness. Pixels classified as cloud or no data were reclassified by: spatial filtering using neighboring pixel values; temporal filtering using pixel values for days before/after cloud cover; and snow-cycle filtering based on a time series assessment of a pixel’s position within snow accumulation, cover or melt periods. During the 2012 snow year, these gap-filling methods reduced cloud pixels from 27.7% to 3.1%. A total of 12 metrics (e.g., date of first and last snow, date of persistent snow cover and periods of intermittence for each pixel were calculated by snow year. A comparison of MODIS-derived snow onset and melt dates with in situ observations from 244 weather stations generally showed an early bias in MODIS-derived dates and an effect of increasing cloudiness exacerbating bias. Our results show that mean regional duration of seasonal snow cover is 179–311 days/year and that snow cover is often intermittent, with 41% of the area experiencing ≥2 snow-covered periods during a snow season. Other regional-scale patterns in the timing of snow onset and melt are evident in the yearly 500 m gridded products publically available at http://static.gina.alaska.edu/NPS_products/MODIS_snow/.

Nitrogen deposition, land cover conversion, and contemporary carbon balance of Europe

Science.gov (United States)

Churkina, G.; Zaehle, S.; Hughes, J.; Viovy, N.; Jung, M.; Chen, Y.; Heimann, M.; Roedenbeck, C.; Jones, C.

2009-04-01

In Europe, atmospheric nitrogen deposition has more than doubled, forest cover was steadily increasing, and agricultural area was declining over the last 50 years. What effect have these changes had on the European carbon balance? In this study we estimate responses of the European land ecosystems to nitrogen deposition, land cover conversion and climate. We use results from four ecosystem process models such as BIOME-BGC, JULES, ORCHIDEE, and ORCHIDEE-CN to address this question. We discuss to which degree carbon balance of Europe has been altered by nitrogen deposition in comparison to other drivers and identify areas which carbon balance has been most effected by anthropogenic changes.

Treatment of esophagopleural fistulas using covered retrievable expandable metallic stents.

Science.gov (United States)

Kim, Tae-Hyung; Shin, Ji Hoon; Kim, Kyung Rae; Park, Jung-Hoon; Kim, Jin Hyoung; Song, Ho-Young

2014-04-01

To evaluate the clinical efficacy of placement of covered retrievable expandable metallic stents for esophagopleural fistulas (EPFs). During the period 1997-2013, nine patients with EPF were treated using covered retrievable expandable metallic stents. The underlying causes of EPF were esophageal carcinoma (n = 6), lung cancer (n = 2), and postoperative empyema for Boerhaave syndrome (n = 1). Technical success was achieved in eight patients (88.9%). In one patient, incomplete EPF closure was due to incomplete stent expansion. Clinical success, defined as complete EPF closure within 7 days, was achieved in five patients (55.6%). Overall fistula persistence (n = 1) or reopening (n = 4) occurred in five patients (55.6%) 0-15 days after stent placement. The causes of reopening were due to the gap between the stent and the esophagus (n = 3) or stent migration (n = 1). For fistula persistence or reopening, additional interventional management, such as gastrostomy, stent removal, or stent reinsertion, was performed. Stent migration occurred as a complication in one patient with EPF from a benign cause secondary to postoperative empyema. In the eight patients who died during the follow-up period, the mean and median survival times were 78.8 days and 46 days, respectively. Placement of a covered expandable metallic esophageal stent for the palliative treatment of EPF is technically feasible, although the rate of clinical success was poor secondary to fistula persistence or reopening. Fistula reopening was caused by the gap between the stent and the esophagus or by stent migration, and additional interventional treatment was useful to ensure enteral nutritional support. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

Effect of forest fragmentation on the epiphytic lichen cover of pine trunks on the example taiga town

Directory of Open Access Journals (Sweden)

Gaigysh Irina Sergeevna

2012-06-01

Full Text Available The main characteristics of epiphytic lichen cover on pine trunks depending on the area of natural pine forest in Kostomuksha (north Karelia were analysed. The town of Kostomuksha was built so that to provide the conservation of forest sites. 56 fragments with the area of 0.04 - 6.13 ha were studied. The average area of fragment is 0.62 ha, with 49 fragments (88% having the area less than 1 ha. Biodiversity and lichen cover were studied in the each fragment with using framework 10x20 cm. 1792 sample plots were made on 448 trees. The total lichens cover varies from 0 to 85%,averaging 10%. 25 species of lichens were found. The number of species in the sample plots varies from 0 to 9. Dominant species found are Hypogymnia physodes, Parmeliopsis ambigua, P. hyperopta, Imshaugia aleurites, Cladonia. Species Alectoria sarmentosa, Cladonia macilenta, Pseudevernia fufruraceae, Bryoria fremontii were less common. It was shown that the main parameters of lichen cover are closely related to the size of the area left in the city forest fragments. The maximum values of species diversity and cover of lichens were found in the fragments of more 1-2 hectares.

'Covering doctors' standing in for unavailable colleagues: What is ...

African Journals Online (AJOL)

They also cannot rely on telephone instructions for long periods of time when the patient's health may be in danger, without seeing the patient. However, if covering doctors are found to be negligent they can still escape liability if the plaintiff cannot prove a causal link between their negligence and the harm that resulted ...

An Assessment of Forest Cover Trends in South and North Korea, From 1980 to 2010

Science.gov (United States)

Engler, Robin; Teplyakov, Victor; Adams, Jonathan M.

2014-01-01

It is generally believed that forest cover in North Korea has undergone a substantial decrease since 1980, while in South Korea, forest cover has remained relatively static during that same period of time. The United Nations Food and Agriculture Organization (FAO) Forest Resources Assessments—based on the reported forest inventories from North and South Korea—suggest a major forest cover decrease in North Korea, but only a slight decrease in South Korea during the last 30 years. In this study, we seek to check and validate those assessments by comparing them to independently derived forest cover maps compiled for three time intervals between 1990 and 2010, as well as to provide a spatially explicit view of forest cover change in the Korean Peninsula since the 1990s. We extracted tree cover data for the Korean Peninsula from existing global datasets derived from satellite imagery. Our estimates, while qualitatively supporting the FAO results, show that North Korea has lost a large number of densely forested areas, and thus in this sense has suffered heavier forest loss than the FAO assessment suggests. Given the limited time interval studied in our assessment, the overall forest loss from North Korea during the whole span of time since 1980 may have been even heavier than in our estimate. For South Korea, our results indicate that the forest cover has remained relatively stable at the national level, but that important variability in forest cover evolution exists at the regional level: While the northern and western provinces show an overall decrease in forested areas, large areas in the southeastern part of the country have increased their forest cover.

Remote Sensing GIS Based Spatio-temporal Land Use/ Cover Study ...

African Journals Online (AJOL)

Vegetations showed loss and gain changes. Forested areas were diminished greatly due to their conversion to other forms of land use/cover across the whole period. Much of the original dense forests (171.16 sq. km of the area) were lost with 5.186 sq.km average annual loss. Extreme forest loss was recorded during the ...

Using lidar data to analyse sinkhole characteristics relevant for understory vegetation under forest cover-case study of a high karst area in the dinaric mountains.

Directory of Open Access Journals (Sweden)

Milan Kobal

Full Text Available In this article, we investigate the potential for detection and characterization of sinkholes under dense forest cover by using airborne laser scanning data. Laser pulse returns from the ground provide important data for the estimation of digital elevation model (DEM, which can be used for further processing. The main objectives of this study were to map and determine the geomorphometric characteristics of a large number of sinkholes and to investigate the correlations between geomorphology and vegetation in areas with such characteristics. The selected study area has very low anthropogenic influences and is particularly suitable for studying undisturbed karst sinkholes. The information extracted from this study regarding the shapes and depths of sinkholes show significant directionality for both orientation of sinkholes and their distribution over the area. Furthermore, significant differences in vegetation diversity and composition occur inside and outside the sinkholes, which indicates their presence has important ecological impacts.

Using lidar data to analyse sinkhole characteristics relevant for understory vegetation under forest cover-case study of a high karst area in the dinaric mountains.

Science.gov (United States)

Kobal, Milan; Bertoncelj, Irena; Pirotti, Francesco; Dakskobler, Igor; Kutnar, Lado

2015-01-01

In this article, we investigate the potential for detection and characterization of sinkholes under dense forest cover by using airborne laser scanning data. Laser pulse returns from the ground provide important data for the estimation of digital elevation model (DEM), which can be used for further processing. The main objectives of this study were to map and determine the geomorphometric characteristics of a large number of sinkholes and to investigate the correlations between geomorphology and vegetation in areas with such characteristics. The selected study area has very low anthropogenic influences and is particularly suitable for studying undisturbed karst sinkholes. The information extracted from this study regarding the shapes and depths of sinkholes show significant directionality for both orientation of sinkholes and their distribution over the area. Furthermore, significant differences in vegetation diversity and composition occur inside and outside the sinkholes, which indicates their presence has important ecological impacts.

Vegetation cover, tidal amplitude and land area predict short-term marsh vulnerability in Coastal Louisiana

Science.gov (United States)

Schoolmaster, Donald; Stagg, Camille L.; Sharp, Leigh Anne; McGinnis, Tommy S.; Wood, Bernard; Piazza, Sarai

2018-01-01

The loss of coastal marshes is a topic of great concern, because these habitats provide tangible ecosystem services and are at risk from sea-level rise and human activities. In recent years, significant effort has gone into understanding and modeling the relationships between the biological and physical factors that contribute to marsh stability. Simulation-based process models suggest that marsh stability is the product of a complex feedback between sediment supply, flooding regime and vegetation response, resulting in elevation gains sufficient to match the combination of relative sea-level rise and losses from erosion. However, there have been few direct, empirical tests of these models, because long-term datasets that have captured sufficient numbers of marsh loss events in the context of a rigorous monitoring program are rare. We use a multi-year data set collected by the Coastwide Reference Monitoring System (CRMS) that includes transitions of monitored vegetation plots to open water to build and test a predictive model of near-term marsh vulnerability. We found that despite the conclusions of previous process models, elevation change had no ability to predict the transition of vegetated marsh to open water. However, we found that the processes that drive elevation change were significant predictors of transitions. Specifically, vegetation cover in prior year, land area in the surrounding 1 km2 (an estimate of marsh fragmentation), and the interaction of tidal amplitude and position in tidal frame were all significant factors predicting marsh loss. This suggests that 1) elevation change is likely better a predictor of marsh loss at time scales longer than we consider in this study and 2) the significant predictive factors affect marsh vulnerability through pathways other than elevation change, such as resistance to erosion. In addition, we found that, while sensitivity of marsh vulnerability to the predictive factors varied spatially across coastal Louisiana

Evapotranspiration (ET) covers.

Science.gov (United States)

Rock, Steve; Myers, Bill; Fiedler, Linda

2012-01-01

Evapotranspiration (ET) cover systems are increasingly being used at municipal solid waste (MSW) landfills, hazardous waste landfills, at industrial monofills, and at mine sites. Conventional cover systems use materials with low hydraulic permeability (barrier layers) to minimize the downward migration of water from the surface to the waste (percolation), ET cover systems use water balance components to minimize percolation. These cover systems rely on soil to capture and store precipitation until it is either transpired through vegetation or evaporated from the soil surface. Compared to conventional membrane or compacted clay cover systems, ET cover systems are expected to cost less to construct. They are often aesthetic because they employ naturalized vegetation, require less maintenance once the vegetative system is established, including eliminating mowing, and may require fewer repairs than a barrier system. All cover systems should consider the goals of the cover in terms of protectiveness, including the pathways of risk from contained material, the lifecycle of the containment system. The containment system needs to be protective of direct contact of people and animals with the waste, prevent surface and groundwater water pollution, and minimize release of airborne contaminants. While most containment strategies have been based on the dry tomb strategy of keeping waste dry, there are some sites where adding or allowing moisture to help decompose organic waste is the current plan. ET covers may work well in places where complete exclusion of precipitation is not needed. The U.S. EPA Alternative Cover Assessment Program (ACAP), USDOE, the Nuclear Regulatory Commission, and others have researched ET cover design and efficacy, including the history of their use, general considerations in their design, performance, monitoring, cost, current status, limitations on their use, and project specific examples. An on-line database has been developed with information

Clearance of buildings for demolition: ways to clearance on the standing structure for covered surfaces and inaccessible areas

International Nuclear Information System (INIS)

Thraenert, S.; Riemann, T.

2014-01-01

structure for about half of this area, and until 2014 most of the remaining area will be treated accordingly. However, due to the building design of Wuergassen NPP, not all surfaces are directly accessible to full-area characterization on the standing structure and not all areas can be completely decontaminated in a cost-effective manner. The most prominent structure is the open gap between the turbine foundations and the surrounding turbine building, but similar gaps also exist between the turbine building and, e.g., the reactor building. In addition, the lower basement floors of the RCA buildings consist of several horizontal layers of concrete which, during construction, did not completely bond. As a result, contaminated liquids propagated along the existing boundary surfaces and hot spots up to 100 kBq are now covered by about 0.5 m of low-activity material. For this variety of challenging examples Wuergassen NPP proposed the release process to the competent authority, performed measurements and provided interpretation of the data. The release process is aimed at verifying compliance with the clearance levels on the standing structure. TUV NORD Nuclear is involved in the release process on behalf of the competent authority to expertise the procedure, to supervise the measurements and to review the data evaluation. Regarding the boundary surfaces between two concrete layers it was possible to gain access to the covered surface by fragmenting the upper concrete layer into blocks. The decontaminated surfaces comply with the clearance levels and the decontaminated concrete blocks may remain on site. An existing gap between the turbine building and the reactor building was characterized by using special equipment. It could be shown, that the residual contamination within the gap complies with the clearance levels. If it is not possible to do a complete decontamination according to static reasons, the residual radioactivity can be determined for further use in the dose

Comparison and assessment of coarse resolution land cover maps for Northern Eurasia

Science.gov (United States)

Dirk Pflugmacher; Olga N. Krankina; Warren B. Cohen; Mark A. Friedl; Damien Sulla-Menashe; Robert E. Kennedy; Peder Nelson; Tatiana V. Loboda; Tobias Kuemmerle; Egor Dyukarev; Vladimir Elsadov; Viacheslav I. Kharuk

2011-01-01

Information on land cover at global and continental scales is critical for addressing a range of ecological, socioeconomic and policy questions. Global land cover maps have evolved rapidly in the last decade, but efforts to evaluate map uncertainties have been limited, especially in remote areas like Northern Eurasia. Northern Eurasia comprises a particularly diverse...

Elective implantation of covered stents for coarctation and recoarctation in adolescents and adults.

Science.gov (United States)

Alcibar, Juan; Blanco, Roberto; Fernandez, Luis; Arriola, Josune; Garcia, Koldobika; Peña, Natividad; Inguanzo, Ramón; Voces, Roberto; Castellanos, Enrique; Montes, Pedro M

2013-06-01

Stent implantation is an effective therapy for aortic coarctation and recoarctation. However, in adolescents and adults, aortic wall rupture and dissection can occur, as well as aneurysms during follow-up. In order to reduce these complications, we electively implant covered stents. Since 2005, we have performed the procedure using femoral access in 17 patients (2 adolescents and 15 adults), 16 electively and 1 as a rescue procedure. We used the Mullins technique in all cases, implanting a NuMED(®) covered stent. Good stent apposition was achieved in all 17 procedures; 8 patients required a distal flare. Gradient was reduced from 40 (16) mmHg to 2 (2) mmHg (P<.001) and lumen diameter increased from 4 (2) mm to 19 (3) mm (P<.001). Two exceptional cases are discussed: one patient with aortic wall rupture who underwent a rescue procedure using a stent within a covered stent and another patient with total obstruction and intercostal aneurysm in whom the outcome was fatal at 48 h postprocedure (autopsy is shown). Four-year clinical follow-up included Doppler echocardiography; an additional imaging technique was required in 13 patients. All patients recovered well and there were no complications. Covered stents are effective in treating coarctation and recoarctation in adolescents and adults, are the treatment of choice in patients with complex anatomy, and must be available in the operating room as a rescue device when implanting a conventional stent. Copyright © 2012 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

IDENTIFICATION OF LAND COVER IN THE PAST USING INFRARED IMAGES AT PRESENT

Directory of Open Access Journals (Sweden)

V. Šafář

2012-07-01

Full Text Available Czech landscape is an old residential area used by humans since ancient times. People have influenced it since their arrival and various activities in different periods create landscape layers called a palimpsest. Land Cover of one location could have changed several times. The most important reason is meandering and subsequent straightening of rivers, deforestation, relocation and change in soil layers. These changes in the past affected the present management and it is important to identify them. A suitable tool for the determination of different sites is remote sensing in the infrared spectrum, which monitors changes in the vegetation with the support of archival materials. After identifying the different places you can search the archival materials, how the land cover looked in the past. There have been used these archival materials: maps II. and III. military mapping, basic maps and other maps and historical orthophotomap. Czech Republic has a national archive of aerial photographs with aerial photographs from the thirties of the last century maintained by MGHO Dobruska. A comparative analysis of Land Cover shows the increases and decreases in agricultural land, changes in communication line elements, forest losses and increases, comparing the legal and actual status of the forest boundaries and their changes over time, changes in the built areas and links to the surrounding countryside. Land Cover of this study was created primarily with a visual interpretation of each area with their vectorization and assigning attributes to these areas and then comparing each of archival materials.

Examination of the semi-automatic calculation technique of vegetation cover rate by digital camera images.

Science.gov (United States)

Takemine, S.; Rikimaru, A.; Takahashi, K.

The rice is one of the staple foods in the world High quality rice production requires periodically collecting rice growth data to control the growth of rice The height of plant the number of stem the color of leaf is well known parameters to indicate rice growth Rice growth diagnosis method based on these parameters is used operationally in Japan although collecting these parameters by field survey needs a lot of labor and time Recently a laborsaving method for rice growth diagnosis is proposed which is based on vegetation cover rate of rice Vegetation cover rate of rice is calculated based on discriminating rice plant areas in a digital camera image which is photographed in nadir direction Discrimination of rice plant areas in the image was done by the automatic binarization processing However in the case of vegetation cover rate calculation method depending on the automatic binarization process there is a possibility to decrease vegetation cover rate against growth of rice In this paper a calculation method of vegetation cover rate was proposed which based on the automatic binarization process and referred to the growth hysteresis information For several images obtained by field survey during rice growing season vegetation cover rate was calculated by the conventional automatic binarization processing and the proposed method respectively And vegetation cover rate of both methods was compared with reference value obtained by visual interpretation As a result of comparison the accuracy of discriminating rice plant areas was increased by the proposed

Supraglacial Ponds Regulate Runoff From Himalayan Debris-Covered Glaciers

Science.gov (United States)

Irvine-Fynn, Tristram D. L.; Porter, Philip R.; Rowan, Ann V.; Quincey, Duncan J.; Gibson, Morgan J.; Bridge, Jonathan W.; Watson, C. Scott; Hubbard, Alun; Glasser, Neil F.

2017-12-01

Meltwater and runoff from glaciers in High Mountain Asia is a vital freshwater resource for one-fifth of the Earth's population. Between 13% and 36% of the region's glacierized areas exhibit surface debris cover and associated supraglacial ponds whose hydrological buffering roles remain unconstrained. We present a high-resolution meltwater hydrograph from the extensively debris-covered Khumbu Glacier, Nepal, spanning a 7 month period in 2014. Supraglacial ponds and accompanying debris cover modulate proglacial discharge by acting as transient and evolving reservoirs. Diurnally, the supraglacial pond system may store >23% of observed mean daily discharge, with mean recession constants ranging from 31 to 108 h. Given projections of increased debris cover and supraglacial pond extent across High Mountain Asia, we conclude that runoff regimes may become progressively buffered by the presence of supraglacial reservoirs. Incorporation of these processes is critical to improve predictions of the region's freshwater resource availability and cascading environmental effects downstream.

Complementarity and Area-Efficiency in the Prioritization of the Global Protected Area Network.

Directory of Open Access Journals (Sweden)

Peter Kullberg

Full Text Available Complementarity and cost-efficiency are widely used principles for protected area network design. Despite the wide use and robust theoretical underpinnings, their effects on the performance and patterns of priority areas are rarely studied in detail. Here we compare two approaches for identifying the management priority areas inside the global protected area network: 1 a scoring-based approach, used in recently published analysis and 2 a spatial prioritization method, which accounts for complementarity and area-efficiency. Using the same IUCN species distribution data the complementarity method found an equal-area set of priority areas with double the mean species ranges covered compared to the scoring-based approach. The complementarity set also had 72% more species with full ranges covered, and lacked any coverage only for half of the species compared to the scoring approach. Protected areas in our complementarity-based solution were on average smaller and geographically more scattered. The large difference between the two solutions highlights the need for critical thinking about the selected prioritization method. According to our analysis, accounting for complementarity and area-efficiency can lead to considerable improvements when setting management priorities for the global protected area network.

Complementarity and Area-Efficiency in the Prioritization of the Global Protected Area Network.

Science.gov (United States)

Kullberg, Peter; Toivonen, Tuuli; Montesino Pouzols, Federico; Lehtomäki, Joona; Di Minin, Enrico; Moilanen, Atte

2015-01-01

Complementarity and cost-efficiency are widely used principles for protected area network design. Despite the wide use and robust theoretical underpinnings, their effects on the performance and patterns of priority areas are rarely studied in detail. Here we compare two approaches for identifying the management priority areas inside the global protected area network: 1) a scoring-based approach, used in recently published analysis and 2) a spatial prioritization method, which accounts for complementarity and area-efficiency. Using the same IUCN species distribution data the complementarity method found an equal-area set of priority areas with double the mean species ranges covered compared to the scoring-based approach. The complementarity set also had 72% more species with full ranges covered, and lacked any coverage only for half of the species compared to the scoring approach. Protected areas in our complementarity-based solution were on average smaller and geographically more scattered. The large difference between the two solutions highlights the need for critical thinking about the selected prioritization method. According to our analysis, accounting for complementarity and area-efficiency can lead to considerable improvements when setting management priorities for the global protected area network.

Factors influencing quality of patient interaction at community pharmacy drive-through and walk-in counselling areas.

Science.gov (United States)

Odukoya, Olufunmilola K; Chui, Michelle A; Pu, Jia

2014-08-01

To examine factors influencing the amount of time and information pharmacy personnel provide to patients at drive-through and walk-in counselling areas. On-site observational data collection in 22 community pharmacies by pharmacy students. Information included observable patient characteristics such as gender, age range, English proficiency and mobility impairment; encounter characteristics included type of prescription and whether the patient was acknowledged; and counselling characteristics included types of counselling information conveyed and length of time for each encounter. Patient-pharmacist encounters were documented at the drive-through and walk-in counselling areas 961 and 1098 times respectively. Pharmacists spent less time, and technicians more time, with patients at the drive-through counselling area. The amount of information provided to patients was significantly affected by whether the patient was receiving new versus refill prescriptions. Patients with a new prescription were twice as likely to receive more information from pharmacy personnel. There was a significant difference between the amount of counselling provided to patients at the drive-through and walk-in counselling area (rate ratio (RR) 0.92, 95% confidence interval (CI): 0.86-1.00). Patients at the drive-through received a lower amount of information relative to patients using the walk-in. Amount of information provided to patients was affected by the level of pharmacy busyness (RR 0.96, 95% CI: 0.95-0.99). Providing patient care at the drive-through counselling area may negatively influence quality of patient care. To improve quality of pharmacy drive-through services, standardization of drive-through services in pharmacies may be needed. © 2013 Royal Pharmaceutical Society.

Land use/land cover study of urban features using spot imagery

International Nuclear Information System (INIS)

Mahmood, S.A.; Qureshi, J.; Abbas, I.

2005-01-01

This study is based on visual interpretation and classification of the urban area of Peshawar. Cloud free satellite image of the French SPOT System in panchromatic mode at 100m/pixel spatial detail was used for this purpose. The coverage area comprised nearly (7.5 x 6)sq. km. on the ground depicting the major portion of the city. Various image interpretation elements were exploited to accomplish the study, thirteen land cover classes were identified and demarcated on a tracing sheet. Having prepared the base map. Satellite image map was constructed by assigning disparate colors to the identified features. Dimensions of some of the prominent, regular and liner features were computed from the image. The results indicate that high-resolution satellite image can be effectively used for mapping and area estimation of urban land use/land cover features. (author)

An Algorithm Approach for the Analysis of Urban Land-Use/Cover: Logic Filters

Directory of Open Access Journals (Sweden)

Şinasi Kaya

2014-11-01

Full Text Available Accurate classification of land-use/cover based on remotely sensed data is important for interpreters who analyze time or event-based change on certain areas. Any method that has user flexibility on area selection provides great simplicity during analysis, since the analyzer may need to work on a specific area of interest instead of dealing with the entire remotely sensed data. The objectives of the paper are to develop an automation algorithm using Matlab & Simulink on user selected areas, to filter V-I-S (Vegetation, Impervious, Soil components using the algorithm, to analyze the components according to upper and lower threshold values based on each band histogram, and finally to obtain land-use/cover map combining the V-I-S components. LANDSAT 5TM satellite data covering Istanbul and Izmit regions are utilized, and 4, 3, 2 (RGB band combination is selected to fulfill the aims of the study. These referred bands are normalized, and V-I-S components of each band are determined. This methodology that uses Matlab & Simulink program is equally successful like the unsupervised and supervised methods. Practices with these methods that lead to qualitative and quantitative assessments of selected urban areas will further provide important spatial information and data especially to the urban planners and decision-makers.

Forest cover change and fragmentation using Landsat data in Maçka State Forest Enterprise in Turkey.

Science.gov (United States)

Cakir, Günay; Sivrikaya, Fatih; Keleş, Sedat

2008-02-01

Monitoring forest cover change and understanding the dynamic of forest cover is increasingly important in sustainable development and management of forest ecosystems. This paper uses remote sensing (RS) techniques to monitor forest cover change in Maçka State Forest Enterprise (MSFE) located in NE of Turkey through 1975 to 2000 and then analyses spatial and temporal changes in forest cover by Geographical Information Systems (GIS) and FRAGSTATStrade mark. Forest cover changes were detected from a time series of satellite images of Landsat MSS in 1975, Landsat TM in 1987, and Landsat ETM+ in 2000 using RS and GIS. The results showed that total forest area, productive forest area and degraded forest area increased while broadleaf forest area and non forest area decreased. Mixed forest and degraded forest increased during the first (1975-1987) period, but decreased during the second (1987-2000) period. During the whole study period, the annual forestation rate was 152 ha year(-1), equivalent to 0.27% year(-1) using the compound-interest-rate formula. The total number of patches increased from 36,204 to 48,092 (33%), and mean size of forest patch (MPS) decreased from 2.8 ha to 2.1 ha during a 25 year period. Number of smaller patches (patches in 0-100 ha size class) increased, indicating more fragmented landscape over time that might create a risk for the maintenance of biodiversity of the area. While total population increased from 1975 to 2000 (3.7%), rural population constantly decreased. The increase of forest areas may well be explained by the fact that demographic movement of rural areas concentrated into Maçka City Center. These figures also indicated that decrease in the rural population might likely lead to the release of human pressure to forest areas, probably resulting in a positive development of forest areas.

Patients with MAC Lung Disease Have a Low Visceral Fat Area and Low Nutrient Intake

Directory of Open Access Journals (Sweden)

Kentaro Wakamatsu

2015-01-01

Full Text Available Objective. This study aimed to examine the nutritional status and nutrient intake of patients with MAC lung disease with a focus on visceral fat area. Patients and Methods. Among 116 patients of our hospital with nontuberculous mycobacteriosis who were registered between May 2010 and August 2011, 103 patients with MAC lung disease were included in this study. In all patients, nutritional status and nutrient intake were prospectively examined. Results. Patients were 23 men and 80 women (mean age, 72.3±10.9 years. BMI (kg/m2 at the time of registration was 20.4±2.7 in men and 19.2±2.9 in women. Visceral fat area (cm2 was significantly lower in women (35.7±26.6 than in men (57.5±47.4 (p=0.0111. The comparison with general healthy adults according to age revealed a markedly reduced visceral fat area among patients with MAC lung disease. With respect to nutrient intake, energy adequacy (86.1±15.7%, protein adequacy (82.4±18.2%, lipid adequacy (78.1±21.8%, and carbohydrate adequacy (89.6±19.2% ratios were all low at the time of registration. BMI was significantly correlated with protein adequacy (p=0.0397 and lipid adequacy (p=0.0214 ratios, while no association was found between visceral fat area and nutrient intake. Conclusion. Patients with MAC lung disease had a low visceral fat area and low nutrient intake.

Etomidate accurately localizes the epileptic area in patients with temporal lobe epilepsy.

Science.gov (United States)

Pastor, Jesús; Wix, Rybel; Meilán, María Luisa; Martínez-Chacón, José Luís; de Dios, Eva; Domínguez-Gadea, Luis; Herrera-Peco, Iván; Sola, Rafael G

2010-04-01

A variety of drugs have been used to activate and identify the epileptogenic area in patients during presurgical evaluation. We have evaluated the safety and usefulness of etomidate in identifying the epileptic zone by measuring bioelectrical brain activity and cerebral blood flow (CBF). We studied 13 men and 9 women under presurgical evaluation for temporal lobe epilepsy. We applied etomidate (0.1 mg/kg) while patients were monitored by video-electroencephalography (VEEG) with foramen ovale electrodes. In a subset of 15 patients, we also measured CBF with single photon emission computed tomography (SPECT). (1) Etomidate induced seizures in 2 of 22 patients. (2) The main side-effects observed were myoclonus (14 of 20) and moderate pain (3 of 20). (3) No changes in capillary oxygen saturation, respiration, or heart rate were observed. (4) Irritative activity specifically increased in the temporal mesial and lateral areas. No spikes were observed in other areas, aside from those observed under baseline conditions. (5) Irritative activity induced by etomidate correctly lateralized the ictal onset zone in 19 of 20 patients. In addition, the two etomidate-induced seizures appeared in the same regions as spontaneous ones. (6) The kinetics of pharmacologically induced activity was higher in the region of the ictal-onset zone. (7) Etomidate increased the CBF in the basal ganglia and especially in the posterior hippocampus of the temporal mesial region contralateral to the ictal-onset zone. Etomidate activation is a safe, specific, and quick test that can be used to identify the epileptic region in patients evaluated as candidates for temporal lobe epilepsy surgery.

Long Term Follow-up of a Transjugular Intrahepatic Portosystemic Shunt: A Comparison of Covered and Uncovered Stents

Energy Technology Data Exchange (ETDEWEB)

Joo, Seung Moon; Park, Jae Hyung; Kim, Hyo Cheol; Jae, Hwan Jun; Chung, Jin Wook [Seoul National University Hospital, Seoul (Korea, Republic of)

2009-01-15

To evaluate the long term patency of transjugular intrahepatic portosystemic shunts (TIPS) and to compare the patency rate of covered and uncovered stents in TIPS. The study population included 78 patients with portal hypertension that underwent TIPS between January 1999 and July 2007 at our institution using uncovered stents in 53 patients and covered stents in 25 patients. The primary and secondary patency rates of TIPS were estimated to compare the uncovered and covered stent groups. The primary and secondary patency rates of the TIPS patients were found to be 83.9% and 93.9% at the 6 month follow-up and 73.5% and 88.5% at the12 month follow-up for uncovered and covered stents, respectively. A breakdown patency rates for the 12 month follow-up revealed that the primary patency rates were 76.6% and 66.3% for uncovered and covered stents, respectively; whereas, the secondary patency rates were 94.3% and 73.8% for the uncovered and covered stents, respectively. A comparative analysis did not provide evidence to suggest that a difference exists between the patency rates of the uncovered and covered stent groups (p>0.05). No significant difference was found between the patency rates of the uncovered and covered stent groups. A follow-up to this study would be a more thorough randomized evaluation of the different types of covered stents to compare long-term patency rates.

Land Cover

Data.gov (United States)

Kansas Data Access and Support Center — The Land Cover database depicts 10 general land cover classes for the State of Kansas. The database was compiled from a digital classification of Landsat Thematic...

Chemical elements contamination of snow cover in region of coal production 'Karazhyra'

International Nuclear Information System (INIS)

Evlampieva, E.P.; Panin, M.S.

2008-01-01

Peculiarities of space distribution of chemical elements in hardphase and water-soluble falls of snow cover in region of coal deposit 'Karazhyra' are investigated. The maximal, minimal and background areas of elements accumulation in the snow of this region and distribution of their cumulative rates are determined. The main pollutants of snow cover unto background level are revealed.

Monitoring Areal Snow Cover Using NASA Satellite Imagery

Science.gov (United States)

Harshburger, Brian J.; Blandford, Troy; Moore, Brandon

2011-01-01

The objective of this project is to develop products and tools to assist in the hydrologic modeling process, including tools to help prepare inputs for hydrologic models and improved methods for the visualization of streamflow forecasts. In addition, this project will facilitate the use of NASA satellite imagery (primarily snow cover imagery) by other federal and state agencies with operational streamflow forecasting responsibilities. A GIS software toolkit for monitoring areal snow cover extent and producing streamflow forecasts is being developed. This toolkit will be packaged as multiple extensions for ArcGIS 9.x and an opensource GIS software package. The toolkit will provide users with a means for ingesting NASA EOS satellite imagery (snow cover analysis), preparing hydrologic model inputs, and visualizing streamflow forecasts. Primary products include a software tool for predicting the presence of snow under clouds in satellite images; a software tool for producing gridded temperature and precipitation forecasts; and a suite of tools for visualizing hydrologic model forecasting results. The toolkit will be an expert system designed for operational users that need to generate accurate streamflow forecasts in a timely manner. The Remote Sensing of Snow Cover Toolbar will ingest snow cover imagery from multiple sources, including the MODIS Operational Snowcover Data and convert them to gridded datasets that can be readily used. Statistical techniques will then be applied to the gridded snow cover data to predict the presence of snow under cloud cover. The toolbar has the ability to ingest both binary and fractional snow cover data. Binary mapping techniques use a set of thresholds to determine whether a pixel contains snow or no snow. Fractional mapping techniques provide information regarding the percentage of each pixel that is covered with snow. After the imagery has been ingested, physiographic data is attached to each cell in the snow cover image. This data

CORINE Land Cover 2000 (IandCLC2000)

International Nuclear Information System (INIS)

Novacek, J.

2005-01-01

Remote Sensing for the Earth is one of the method for obtaining of information about objects of the Earth surface. Satellite snapshots were basic source of information for this project. Slovak Environmental Agency was the coordinator of this project to the Slovak Republic and co-research organisation was Geographic Institute, Slovak Academy of Sciences. Interpretation of satellite snapshots enabled to obtain information about position and area of natural ranges of 44 classes of landscape cover of Europe, from which in the Slovakia occurs 31 classes. Resulting thematic layers of landscape cover of the Slovakia during the years 1990 and 2000 are significant for analysis of trends, reasons and implications of nature and social processes which proceeds in the time and place of given territory

Land-Cover Change Analysis and Simulation in Conakry (Guinea, Using Hybrid Cellular-Automata and Markov Model

Directory of Open Access Journals (Sweden)

Arafan Traore

2018-04-01

Full Text Available In this study, land-cover change in the capital Conakry of Guinea was simulated using the integrated Cellular Automata and Markov model (CA-Markov in the Geographic Information System (GIS and Remote Sensing (RS. Historical land-cover change information was derived from 1986, 2000 and 2016 Landsat data. Using the land-cover change maps of 1986 and 2000, the land-cover change map for 2016 was simulated based on the Markov model in IDRISSI software (Clark University, Worcester, MA, USA. The simulated result was compared with the 2016 land-cover map for validation using the Relative Operating Characteristic (ROC. The ROC result showed a very strong agreement between the two maps. From this result, the land-cover change map for 2025 was simulated using CA-Markov model. The result has indicated that the proportion of the urban area was 49% in 2016, and it is expected to increase to 52% by 2025, while vegetation will decrease from 35% in 2016 to 32% in 2025. This study suggests that the rapid land-cover change has been led by both rapid population growth and extreme poverty in rural areas, which will result in migration into Conakry. The results of this study will provide bases for assessing the sustainability and the management of the urban area and for taking actions to mitigate the degradation of the urban environment.

Estimation of Tree Cover in an Agricultural Parkland of Senegal Using Rule-Based Regression Tree Modeling

Directory of Open Access Journals (Sweden)

Stefanie M. Herrmann

2013-10-01

Full Text Available Field trees are an integral part of the farmed parkland landscape in West Africa and provide multiple benefits to the local environment and livelihoods. While field trees have received increasing interest in the context of strengthening resilience to climate variability and change, the actual extent of farmed parkland and spatial patterns of tree cover are largely unknown. We used the rule-based predictive modeling tool Cubist® to estimate field tree cover in the west-central agricultural region of Senegal. A collection of rules and associated multiple linear regression models was constructed from (1 a reference dataset of percent tree cover derived from very high spatial resolution data (2 m Orbview as the dependent variable, and (2 ten years of 10-day 250 m Moderate Resolution Imaging Spectrometer (MODIS Normalized Difference Vegetation Index (NDVI composites and derived phenological metrics as independent variables. Correlation coefficients between modeled and reference percent tree cover of 0.88 and 0.77 were achieved for training and validation data respectively, with absolute mean errors of 1.07 and 1.03 percent tree cover. The resulting map shows a west-east gradient from high tree cover in the peri-urban areas of horticulture and arboriculture to low tree cover in the more sparsely populated eastern part of the study area. A comparison of current (2000s tree cover along this gradient with historic cover as seen on Corona images reveals dynamics of change but also areas of remarkable stability of field tree cover since 1968. The proposed modeling approach can help to identify locations of high and low tree cover in dryland environments and guide ground studies and management interventions aimed at promoting the integration of field trees in agricultural systems.

Left atrial low-voltage areas predict atrial fibrillation recurrence after catheter ablation in patients with paroxysmal atrial fibrillation.

Science.gov (United States)

Masuda, Masaharu; Fujita, Masashi; Iida, Osamu; Okamoto, Shin; Ishihara, Takayuki; Nanto, Kiyonori; Kanda, Takashi; Tsujimura, Takuya; Matsuda, Yasuhiro; Okuno, Shota; Ohashi, Takuya; Tsuji, Aki; Mano, Toshiaki

2018-04-15

Association between the presence of left atrial low-voltage areas and atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) has been shown mainly in persistent AF patients. We sought to compare the AF recurrence rate in paroxysmal AF patients with and without left atrial low-voltage areas. This prospective observational study included 147 consecutive patients undergoing initial ablation for paroxysmal AF. Voltage mapping was performed after PVI during sinus rhythm, and low-voltage areas were defined as regions where bipolar peak-to-peak voltage was low-voltage areas after PVI were observed in 22 (15%) patients. Patients with low-voltage areas were significantly older (72±6 vs. 66±10, plow-voltage areas than without (36% vs. 6%, pLow-voltage areas were independently associated with AF recurrence even after adjustment for the other related factors (Hazard ratio, 5.89; 95% confidence interval, 2.16 to 16.0, p=0.001). The presence of left atrial low-voltage areas after PVI predicts AF recurrence in patients with paroxysmal AF as well as in patients with persistent AF. Copyright © 2017 Elsevier B.V. All rights reserved.

A phantom based method for deriving typical patient doses from measurements of dose-area product on populations of patients

International Nuclear Information System (INIS)

Chapple, C.-L.; Broadhead, D.A.

1995-01-01

One of the chief sources of uncertainty in the comparison of patient dosimetry data is the influence of patient size on dose. Dose has been shown to relate closely to the equivalent diameter of the patient. This concept has been used to derive a prospective, phantom based method for determining size correction factors for measurements of dose-area product. The derivation of the size correction factor has been demonstrated mathematically, and the appropriate factor determined for a number of different X-ray sets. The use of phantom measurements enables the effect of patient size to be isolated from other factors influencing patient dose. The derived factors agree well with those determined retrospectively from patient dose survey data. Size correction factors have been applied to the results of a large scale patient dose survey, and this approach has been compared with the method of selecting patients according to their weight. For large samples of data, mean dose-area product values are independent of the analysis method used. The chief advantage of using size correction factors is that it allows all patient data to be included in a survey, whereas patient selection has been shown to exclude approximately half of all patients. (author)

Landspotting: collecting essential land cover information via an attractive internet game

Science.gov (United States)

Fritz, Steffen; McCallum, Ian; Perger, Christoph; Christian, Schill; Florian, Kraxner; Erik, Lindquist; Michael, Obersteiner

2010-05-01

Based on the geo-wiki.org concept of collecting land cover information via crowdsourcing, we present a novel approach on how to get the crowd involved. Internet games as well as social networks are becoming increasingly popular and the full potential is yet to be exploited. However, thus far, few if any games provide anything other than entertainment. Can an attractive philanthropic game be created which uses the crowd to collect essential information needed to help to acquire better data to improve the understanding of the earth system? Since accurate and up to date information on global land cover plays a very important role in a number of different research fields such as climate change, monitoring of tropical deforestation, land use monitoring and land-use modelling, but still shows high levels of disagreement, the game will focus on how this essential land cover calibration and validation data can be collected in areas where uncertainty is currently highest. In the current version of the land spotting game, we combine uncertainty hotspot information from three global land cover datasets (GLC, MODIS and GlobCover). With an ever increasing amount of high resolution images available on Google Earth, it is becoming increasingly possible to distinguish land cover features with a high degree of accuracy. We first direct the landspotting game community to certain hotspots of land cover uncertainty and then ask them to enter/record the type of land cover they see (for this they will be able to acquire a certain number of points), possibly uploading pictures at that location (additional points will be received). Even though the development of the game "landspotting.org" is still underway, we illustrate what the functionality will be and what features are envisaged for the near future. Landspotting.org will be designed in such a way as to challenge users to help map out the remaining areas of confusion over the globe - possibly in the form of an adventure game. Users

Canopy cover negatively affects arboreal ant species richness in a tropical open habitat

Directory of Open Access Journals (Sweden)

A. C. M. Queiroz

Full Text Available Abstract We tested the hypothesis of a negative relationship between vegetation characteristics and ant species richness in a Brazilian open vegetation habitat, called candeial. We set up arboreal pitfalls to sample arboreal ants and measured the following environmental variables, which were used as surrogate of environmental heterogeneity: tree richness, tree density, tree height, circumference at the base of the plants, and canopy cover. Only canopy cover had a negative effect on the arboreal ant species richness. Vegetation characteristics and plant species composition are probably homogeneous in candeial, which explains the lack of relationship between other environmental variables and ant richness. Open vegetation habitats harbor a large number of opportunistic and generalist species, besides specialist ants from habitats with high temperatures. An increase in canopy cover decreases sunlight incidence and may cause local microclimatic differences, which negatively affect the species richness of specialist ants from open areas. Canopy cover regulates the richness of arboreal ants in open areas, since only few ant species are able to colonize sites with dense vegetation; most species are present in sites with high temperature and luminosity. Within open vegetation habitats the relationship between vegetation characteristics and species richness seems to be the opposite from closed vegetation areas, like forests.

Prevalence of Pure Versus Mixed Snow Cover Pixels across Spatial Resolutions in Alpine Environments

Directory of Open Access Journals (Sweden)

David J. Selkowitz

2014-12-01

Full Text Available Remote sensing of snow-covered area (SCA can be binary (indicating the presence/absence of snow cover at each pixel or fractional (indicating the fraction of each pixel covered by snow. Fractional SCA mapping provides more information than binary SCA, but is more difficult to implement and may not be feasible with all types of remote sensing data. The utility of fractional SCA mapping relative to binary SCA mapping varies with the intended application as well as by spatial resolution, temporal resolution and period of interest, and climate. We quantified the frequency of occurrence of partially snow-covered (mixed pixels at spatial resolutions between 1 m and 500 m over five dates at two study areas in the western U.S., using 0.5 m binary SCA maps derived from high spatial resolution imagery aggregated to fractional SCA at coarser spatial resolutions. In addition, we used in situ monitoring to estimate the frequency of partially snow-covered conditions for the period September 2013–August 2014 at 10 60-m grid cell footprints at two study areas with continental snow climates. Results from the image analysis indicate that at 40 m, slightly above the nominal spatial resolution of Landsat, mixed pixels accounted for 25%–93% of total pixels, while at 500 m, the nominal spatial resolution of MODIS bands used for snow cover mapping, mixed pixels accounted for 67%–100% of total pixels. Mixed pixels occurred more commonly at the continental snow climate site than at the maritime snow climate site. The in situ data indicate that some snow cover was present between 186 and 303 days, and partial snow cover conditions occurred on 10%–98% of days with snow cover. Four sites remained partially snow-free throughout most of the winter and spring, while six sites were entirely snow covered throughout most or all of the winter and spring. Within 60 m grid cells, the late spring/summer transition from snow-covered to snow-free conditions lasted 17–56 days

DETERMINATION OF LEAF AREA AND PLANT COVER BY USING DIGITAL IMAGE PROCESSING

OpenAIRE

LŐKE, ZS.; SOÓS, G.

2002-01-01

The development of different crop models, and crop simulation models in particular, pointed out the importance of quantifying the exact value of the leaf area. To measure the leaf size of plants of pinnatifid form, automatic, portable leaf area meters are necessary. In most places these instruments are not available to measure the assimilatory surface size of crops with special leaf shapes. Any cheap and effective method, that could replace the application of expensive portable area meters co...

Covered Biodegradable Stent: New Therapeutic Option for the Management of Esophageal Perforation or Anastomotic Leak

International Nuclear Information System (INIS)

Černá, Marie; Köcher, Martin; Válek, Vlastimil; Aujeský, René; Neoral, Čestmír; Andrašina, Tomáš; Pánek, Jiří; Mahathmakanthi, Shankari

2011-01-01

Purpose: This study was designed to evaluate our experience with the treatment of postoperative anastomotic leaks and benign esophageal perforations with covered biodegradable stents. Materials and Methods: From 2008 to 2010, we treated five men with either an anastomotic leak or benign esophageal perforation by implanting of covered biodegradable Ella-BD stents. The average age of the patients was 60 (range, 38–74) years. Postoperative anastomotic leaks were treated in four patients (1 after esophagectomy, 1 after resection of diverticulum, 2 after gastrectomy). In one patient, perforation occurred as a complication of the treatment of an esophageal rupture (which occurred during a balloon dilatation of benign stenosis) with a metallic stent. Results: Seven covered biodegradable stents were implanted in five patients. Primary technical success was 100%. Clinical success (leak sealing) was achieved in four of the five patients (80%). Stent migration occurred in three patients. In two of these patients, the leak had been sealed by the time of stent migration, therefore no reintervention was necessary. In one patient an additional stent had to be implanted. Conclusion: The use of biodegradable covered stents for the treatment of anastomotic leaks or esophageal perforations is technically feasible and safe. The initial results are promising; however, larger number of patients will be required to evaluate the capability of these biodegradable stents in the future. The use of biodegradable material for coverage of the stent is essential.

Characterizing Tropical Forest Cover Loss Using Dense Sentinel-1 Data and Active Fire Alerts

NARCIS (Netherlands)

Reiche, Johannes; Verhoeven, Rob; Verbesselt, Jan; Hamunyela, Eliakim; Wielaard, Niels; Herold, Martin

2018-01-01

Fire use for land management is widespread in natural tropical and plantation forests, causing major environmental and economic damage. Recent studies combining active fire alerts with annual forest-cover loss information identified fire-related forest-cover loss areas well, but do not provide

Object-Based Mapping of the Circumpolar Taiga-Tundra Ecotone with MODIS Tree Cover

Science.gov (United States)

Ranson, K. J.; Montesano, P. M.; Nelson, R.

2011-01-01

The circumpolar taiga tundra ecotone was delineated using an image-segmentation-based mapping approach with multi-annual MODIS Vegetation Continuous Fields (VCF) tree cover data. Circumpolar tree canopy cover (TCC) throughout the ecotone was derived by averaging MODIS VCF data from 2000 to 2005 and adjusting the averaged values using linear equations relating MODIS TCC to Quickbird-derived tree cover estimates. The adjustment helped mitigate VCF's overestimation of tree cover in lightly forested regions. An image segmentation procedure was used to group pixels representing similar tree cover into polygonal features (segmentation objects) that form the map of the transition zone. Each polygon represents an area much larger than the 500 m MODIS pixel and characterizes the patterns of sparse forest patches on a regional scale. Those polygons near the boreal/tundra interface with either (1) mean adjusted TCC values from5 to 20%, or (2) mean adjusted TCC values greater than 5% but with a standard deviation less than 5% were used to identify the ecotone. Comparisons of the adjusted average tree cover data were made with (1) two existing tree line definitions aggregated for each 1 degree longitudinal interval in North America and Eurasia, (2) Landsat-derived Canadian proportion of forest cover for Canada, and (3) with canopy cover estimates extracted from airborne profiling lidar data that transected 1238 of the TCC polygons. The adjusted TCC from MODIS VCF shows, on average, less than 12% TCC for all but one regional zone at the intersection with independently delineated tree lines. Adjusted values track closely with Canadian proportion of forest cover data in areas of low tree cover. A comparison of the 1238 TCC polygons with profiling lidar measurements yielded an overall accuracy of 67.7%.

Modeled impact of anthropogenic land cover change on climate

Science.gov (United States)

Findell, K.L.; Shevliakova, E.; Milly, P.C.D.; Stouffer, R.J.

2007-01-01

Equilibrium experiments with the Geophysical Fluid Dynamics Laboratory's climate model are used to investigate the impact of anthropogenic land cover change on climate. Regions of altered land cover include large portions of Europe, India, eastern China, and the eastern United States. Smaller areas of change are present in various tropical regions. This study focuses on the impacts of biophysical changes associated with the land cover change (albedo, root and stomatal properties, roughness length), which is almost exclusively a conversion from forest to grassland in the model; the effects of irrigation or other water management practices and the effects of atmospheric carbon dioxide changes associated with land cover conversion are not included in these experiments. The model suggests that observed land cover changes have little or no impact on globally averaged climatic variables (e.g., 2-m air temperature is 0.008 K warmer in a simulation with 1990 land cover compared to a simulation with potential natural vegetation cover). Differences in the annual mean climatic fields analyzed did not exhibit global field significance. Within some of the regions of land cover change, however, there are relatively large changes of many surface climatic variables. These changes are highly significant locally in the annual mean and in most months of the year in eastern Europe and northern India. They can be explained mainly as direct and indirect consequences of model-prescribed increases in surface albedo, decreases in rooting depth, and changes of stomatal control that accompany deforestation. ?? 2007 American Meteorological Society.

ORGANIC MATTER AND AGGREGATION OF A PLANOSOL UNDER DIFFERENT FOREST COVERINGS

Directory of Open Access Journals (Sweden)

Julia Kishida Bochner

2008-03-01

Full Text Available The litter quality can alter soil aggregation, modifying the transformation dynamics and allocation of soil carbon (Cin different compartments. This study evaluated the aggregate stability and its relation with litter chemical characteristics, organiccarbon and free light fraction (FLL from the organic matter under three different types of vegetation covering: secondary forest (FSand plantings of Mimosa Caesalpiniaefolia (PM and Carapa guianenses (PA with subsequently natural regeneration. Litter sampleswere characterized using polyfenols, lignin, suberine, tannin and holocelulose content and C/N relationship. Soil samples werecollected in two depths (0-10 and 10-20 cm and soil aggregation were estimate using mean weight diameter (DMP, mean geometricdiameter (DMG and index of aggregate stability (IEA analysis . Soil samples in the same depths were also characterized using C andFLL content. The highest suberine and polyfenols content of the litter found in the areas FS and PM reduced the speed of residuesdecomposition in the soil causing larger FLL content in both coverings. Those compositions contributed to the stabilization of C in themineral phase, because the highest C content was found in those areas. This fact is confirmed by the values of DMP, DMG and IEAamong the areas. They are higher in the coverings, PM and FS. It can be concluded that the polyfenols and suberine content weredecisive in the subdivision of C and in the aggregation of the soil in the areas of FS and PM.

Interrelationships between soil cover and plant cover depending on land use

Directory of Open Access Journals (Sweden)

Tiina Köster

2013-05-01

Full Text Available Interrelationships between soil cover and plant cover of normally developed (or postlithogenic mineral soils are analysed on the basis of four sampling soil groups. The four-link pedo-ecological sequence of analysed soils, rendzinas → brown soils → pseudopodzolic soils → gley-podzols, forms a representative cross section in relation to the normal mineral soils of Estonia. All groups differ substantially from each other in terms of soil properties (calcareousness, acidity, nutrition conditions, profile fabric and humus cover. The primary tasks of the research were (1 to elucidate the main pedo-ecological characteristics of the four soil groups and their suitability for plant cover, (2 to evaluate comparatively soils in terms of productivity, sustainability, biodiversity and environmental protection ability and (3 to analyse possibilities for ecologically sound matching of soil cover with suitable plant cover. On the basis of the same material, the influence of land-use change on humus cover (epipedon fabric, properties of the entire soil cover and soil–plant interrelationship were also analysed. An ecosystem approach enables us to observe particularities caused by specific properties of a soil type (species, variety in biological turnover and in the formation of biodiversity.

The effects of changing land cover on streamflow simulation in Puerto Rico

Science.gov (United States)

Van Beusekom, Ashley; Hay, Lauren E.; Viger, Roland; Gould, William A.; Collazo, Jaime; Henareh Khalyani, Azad

2014-01-01

This study quantitatively explores whether land cover changes have a substantive impact on simulated streamflow within the tropical island setting of Puerto Rico. The Precipitation Runoff Modeling System (PRMS) was used to compare streamflow simulations based on five static parameterizations of land cover with those based on dynamically varying parameters derived from four land cover scenes for the period 1953-2012. The PRMS simulations based on static land cover illustrated consistent differences in simulated streamflow across the island. It was determined that the scale of the analysis makes a difference: large regions with localized areas that have undergone dramatic land cover change may show negligible difference in total streamflow, but streamflow simulations using dynamic land cover parameters for a highly altered subwatershed clearly demonstrate the effects of changing land cover on simulated streamflow. Incorporating dynamic parameterization in these highly altered watersheds can reduce the predictive uncertainty in simulations of streamflow using PRMS. Hydrologic models that do not consider the projected changes in land cover may be inadequate for water resource management planning for future conditions.

An Automated Algorithm for Producing Land Cover Information from Landsat Surface Reflectance Data Acquired Between 1984 and Present

Science.gov (United States)

Rover, J.; Goldhaber, M. B.; Holen, C.; Dittmeier, R.; Wika, S.; Steinwand, D.; Dahal, D.; Tolk, B.; Quenzer, R.; Nelson, K.; Wylie, B. K.; Coan, M.

2015-12-01

Multi-year land cover mapping from remotely sensed data poses challenges. Producing land cover products at spatial and temporal scales required for assessing longer-term trends in land cover change are typically a resource-limited process. A recently developed approach utilizes open source software libraries to automatically generate datasets, decision tree classifications, and data products while requiring minimal user interaction. Users are only required to supply coordinates for an area of interest, land cover from an existing source such as National Land Cover Database and percent slope from a digital terrain model for the same area of interest, two target acquisition year-day windows, and the years of interest between 1984 and present. The algorithm queries the Landsat archive for Landsat data intersecting the area and dates of interest. Cloud-free pixels meeting the user's criteria are mosaicked to create composite images for training the classifiers and applying the classifiers. Stratification of training data is determined by the user and redefined during an iterative process of reviewing classifiers and resulting predictions. The algorithm outputs include yearly land cover raster format data, graphics, and supporting databases for further analysis. Additional analytical tools are also incorporated into the automated land cover system and enable statistical analysis after data are generated. Applications tested include the impact of land cover change and water permanence. For example, land cover conversions in areas where shrubland and grassland were replaced by shale oil pads during hydrofracking of the Bakken Formation were quantified. Analytical analysis of spatial and temporal changes in surface water included identifying wetlands in the Prairie Pothole Region of North Dakota with potential connectivity to ground water, indicating subsurface permeability and geochemistry.

A Review of Land-Cover Mapping Activities in Coastal Alabama and Mississippi

Science.gov (United States)

Smith, Kathryn E.L.; Nayegandhi, Amar; Brock, John C.

2010-01-01

INTRODUCTION Land-use and land-cover (LULC) data provide important information for environmental management. Data pertaining to land-cover and land-management activities are a common requirement for spatial analyses, such as watershed modeling, climate change, and hazard assessment. In coastal areas, land development, storms, and shoreline modification amplify the need for frequent and detailed land-cover datasets. The northern Gulf of Mexico coastal area is no exception. The impact of severe storms, increases in urban area, dramatic changes in land cover, and loss of coastal-wetland habitat all indicate a vital need for reliable and comparable land-cover data. Four main attributes define a land-cover dataset: the date/time of data collection, the spatial resolution, the type of classification, and the source data. The source data are the foundation dataset used to generate LULC classification and are typically remotely sensed data, such as aerial photography or satellite imagery. These source data have a large influence on the final LULC data product, so much so that one can classify LULC datasets into two general groups: LULC data derived from aerial photography and LULC data derived from satellite imagery. The final LULC data can be converted from one format to another (for instance, vector LULC data can be converted into raster data for analysis purposes, and vice versa), but each subsequent dataset maintains the imprint of the source medium within its spatial accuracy and data features. The source data will also influence the spatial and temporal resolution, as well as the type of classification. The intended application of the LULC data typically defines the type of source data and methodology, with satellite imagery being selected for large landscapes (state-wide, national data products) and repeatability (environmental monitoring and change analysis). The coarse spatial scale and lack of refined land-use categories are typical drawbacks to satellite

Low skeletal muscle area is a risk factor for mortality in mechanically ventilated critically ill patients.

Science.gov (United States)

Weijs, Peter J M; Looijaard, Wilhelmus G P M; Dekker, Ingeborg M; Stapel, Sandra N; Girbes, Armand R; Oudemans-van Straaten, H M; Beishuizen, Albertus

2014-01-13

Higher body mass index (BMI) is associated with lower mortality in mechanically ventilated critically ill patients. However, it is yet unclear which body component is responsible for this relationship. This retrospective analysis in 240 mechanically ventilated critically ill patients included adult patients in whom a computed tomography (CT) scan of the abdomen was made on clinical indication between 1 day before and 4 days after admission to the intensive care unit. CT scans were analyzed at the L3 level for skeletal muscle area, expressed as square centimeters. Cutoff values were defined by receiver operating characteristic (ROC) curve analysis: 110 cm2 for females and 170 cm2 for males. Backward stepwise regression analysis was used to evaluate low-muscle area in relation to hospital mortality, with low-muscle area, sex, BMI, Acute Physiologic and Chronic Health Evaluation (APACHE) II score, and diagnosis category as independent variables. This study included 240 patients, 94 female and 146 male patients. Mean age was 57 years; mean BMI, 25.6 kg/m2. Muscle area for females was significantly lower than that for males (102 ± 23 cm2 versus 158 ± 33 cm2; P muscle area was observed in 63% of patients for both females and males. Mortality was 29%, significantly higher in females than in males (37% versus 23%; P = 0.028). Low-muscle area was associated with higher mortality compared with normal-muscle area in females (47.5% versus 20%; P = 0.008) and in males (32.3% versus 7.5%; P muscle area, sex, and APACHE II score, whereas BMI and admission diagnosis were not. Odds ratio for low-muscle area was 4.3 (95% confidence interval, 2.0 to 9.0, P muscle mass appeared as primary predictor, not sex. Low skeletal muscle area, as assessed by CT scan during the early stage of critical illness, is a risk factor for mortality in mechanically ventilated critically ill patients, independent of sex and APACHE II score. Further analysis suggests muscle mass as primary predictor, not

Effective dose in the manufacturing process of rutile covered welding electrodes.

Science.gov (United States)

Herranz, M; Rozas, S; Pérez, C; Idoeta, R; Núñez-Lagos, R; Legarda, F

2013-03-01

Shielded metal arc welding using covered electrodes is the most common welding process. Sometimes the covering contains naturally occurring radioactive materials (NORMs). In Spain the most used electrodes are those covered with rutile mixed with other materials. Rutile contains some detectable natural radionuclides, so it can be considered a NORM. This paper mainly focuses on the use of MCNP (Monte Carlo N-Particle Transport Code) as a predictive tool to obtain doses in a factory which produces this type of electrode and assess the radiological impact in a specific facility after estimating the internal dose.To do this, in the facility, areas of highest radiation and positions of workers were identified, radioactive content of rutile and rutile covered electrodes was measured, and, considering a worst possible scenario, external dose at working points has been calculated using MCNP. This procedure has been validated comparing the results obtained with those from a pressurised ionisation chamber and TLD dosimeters. The internal dose has been calculated using DCAL (dose and risk calculation). The doses range between 8.8 and 394 μSv yr(-1), always lower than the effective dose limit for the public, 1 mSv yr(-1). The highest dose corresponds to the mixing area.

[Complications and the management of fully covered retrievable metal stent placement in benign tracheal stenosis].

Science.gov (United States)

Wang, Zheng-yu; Wang, Yong-li; Chen, Guang-li; Liang, Xi-hong; Wang, Zhen-chang; Ma, Jian-zhong; Wu, Guang-zhong; Zhang, Xiao-ping

2012-11-01

To study complications and the management of the use of covered retrievable expandable metallic stents in the treatment of benign tracheal stenosis. Fully covered retrievable metal stents were placed in 21 patients with benign tracheal stenosis. Stent-related complications and the management were reviewed and analysed. Twenty-eight fully covered retrievable metallic stents were successfully placed fluoroscopically in 21 patients. Stents were removed 4 - 12 months [mean (5.5 ± 2.2) mouths] after placement in all patients. Stent-related complications included granulation tissue (n = 18), stent migration (n = 4), stent expectoration (n = 2), halitosis (n = 8), mucous retention (n = 21) and mucus plugging (n = 1). Granulation tissue was removed with a carbon dioxide laser in 2 patients. Stents were replaced for 2 times and 3 times respectively in 2 patients after stent migration and stent expectoration. An additional stent was placed in 2 patients after stent migration. Symptom of halitosis was relieved after prolonged course of systemic antibiotics treatment in 8 patients. Symptom of mucous retention was relieved with nebulized saline and N-acetylcysteine saline inhalation. Mucous plug was expelled after severe coughing after suctioning using an aspirator in one patient. There were statistically significant differences in stricture diameter, rank of tachypnea and pulmonary function (FEV(1)) in all 21 patients before stent insertion and after stents removal. No patient has experienced recurrence during the follow-up period of 1 - 36 months [mean (23.2 ± 8.0) months]. Fully covered retrievable metallic stent may be a safe and effective in benign tracheal stenosis. Stent-related complications may be effectively managed.

Management Effectiveness and Land Cover Change in Dynamic Cultural Landscapes - Assessing a Central European Biosphere Reserve

Directory of Open Access Journals (Sweden)

Bettina Ohnesorge

2013-12-01

Full Text Available Protected areas are a central pillar of efforts to safeguard biodiversity and ecosystem services, but their contribution to the conservation and management of European cultural landscapes that have complex spatial-temporal dynamics is unclear. The conservation strategy of biosphere reserves aims at integrating biodiversity and ecosystem service conservation with economic development by designating zones of differing protection and use intensities. It is applied worldwide to protect and manage valuable cultural landscapes. Using the example of a German biosphere reserve, we developed a framework to assess the effectiveness of Central European reserves in meeting their land cover related management goals. Based on digital biotope maps, we defined and assessed land cover change processes that were relevant to the reserve management's goals over a period of 13 years. We then compared these changes in the reserve's core, buffer, and transition zones and in a surrounding reference area by means of a geographical information system. (Un-desirable key processes related to management aims were defined and compared for the various zones. We found that - despite an overall land cover persistence of approximately 85% across all zones - differences in land cover changes can be more prominent across zones inside the reserve than between the areas inside and outside of it. The reserve as a whole performed better than the surrounding reference area when using land cover related management goals as a benchmark. However, some highly desirable targets, such as the conversion of coniferous plantations into seminatural forests or the gain of valuable biotope types, affected larger areas in the nonprotected reference area than in the transition zone.

Evolution of the soil cover of soccer fields

Science.gov (United States)

Belobrov, V. P.; Zamotaev, I. V.

2014-04-01

A soccer field can be considered a soil-like technogenic formation (STF). According to the theory of soil cover patterns, the artificially constructed (anthropogenic) soil cover of a soccer field is an analogue of a relatively homogeneous elementary soil area. However, the spatial homogeneity of the upper part (50-80 cm) of the STF of soccer fields is unstable and is subjected to gradual transformation under the impact of pedogenetic processes, agrotechnical loads, and mechanical loads during the games. This transformation is favored by the initial heterogeneity of the deep (buried) parts of the STF profile. The technogenic factors and elementary pedogenetic processes specify the dynamic functioning regime of the STF. In 50-75 years, the upper part of the STF is transformed into soil-like bodies with properties close to those in zonal soils. Certain micro- and nanopatterns of the soil cover are developed within the field creating its spatial heterogeneity.

Examination of the relationship between vegetation cover indices ...

African Journals Online (AJOL)

Therefore it is recommended that agroforestry and land scaping should be embraced in the area with emphasis on short economic trees with moderate crown cover that will allow crops or grasses to grow under it as well as avoid the negative impact of rain water drops from very tall tree that can cause soil erosion.

Changes in Andes snow cover from MODIS data, 2000–2016

Directory of Open Access Journals (Sweden)

F. A. Saavedra

2018-03-01

Full Text Available The Andes span a length of 7000 km and are important for sustaining regional water supplies. Snow variability across this region has not been studied in detail due to sparse and unevenly distributed instrumental climate data. We calculated snow persistence (SP as the fraction of time with snow cover for each year between 2000 and 2016 from Moderate Resolution Imaging Spectroradiometer (MODIS satellite sensors (500 m, 8-day maximum snow cover extent. This analysis is conducted between 8 and 36° S due to high frequency of cloud (>  30 % of the time south and north of this range. We ran Mann–Kendall and Theil–Sens analyses to identify areas with significant changes in SP and snowline (the line at lower elevation where SP  =  20 %. We evaluated how these trends relate to temperature and precipitation from Modern-Era Retrospective Analysis for Research and Applications-2 (MERRA2 and University of Delaware datasets and climate indices as El Niño–Southern Oscillation (ENSO, Southern Annular Mode (SAM, and Pacific Decadal Oscillation (PDO. Areas north of 29° S have limited snow cover, and few trends in snow persistence were detected. A large area (34 370 km2 with persistent snow cover between 29 and 36° S experienced a significant loss of snow cover (2–5 fewer days of snow year−1. Snow loss was more pronounced (62 % of the area with significant trends on the east side of the Andes. We also found a significant increase in the elevation of the snowline at 10–30 m year−1 south of 29–30° S. Decreasing SP correlates with decreasing precipitation and increasing temperature, and the magnitudes of these correlations vary with latitude and elevation. ENSO climate indices better predicted SP conditions north of 31° S, whereas the SAM better predicted SP south of 31° S.

Scale dependency in effectiveness, isolation, and social-ecological spillover of protected areas.

Science.gov (United States)

Ament, Judith M; Cumming, Graeme S

2016-08-01

Protected areas are considered vital for the conservation of biodiversity. Given their central role in many conservation strategies, it is important to know whether they adequately protect biodiversity within their boundaries; whether they are becoming more isolated from other natural areas over time; and whether they play a role in facilitating or reducing land-cover change in their surroundings. We used matching methods and national and local analyses of land-cover change to evaluate the combined effectiveness (i.e., avoided natural-cover loss), isolation (i.e., changes in adjacent areas), and spillover effects (i.e., impacts on adjacent areas) of 19 national parks in South Africa from 2000 to 2009. All parks had either similar or lower rates of natural-cover loss than matched control samples. On a national level, mean net loss of natural cover and mean net gain of cultivation cover decreased with distance from park boundary, but there was considerable variation in trends around individual parks, providing evidence for both increased isolation and buffering of protected areas. Fourteen parks had significant positive spillover and reduced natural-cover loss in their surroundings, whereas five parks experienced elevated levels of natural-cover loss. Conclusions about social-ecological spillover effects from protected areas depended heavily on the measures of land-cover change used and the scale at which the results were aggregated. Our findings emphasize the need for high-resolution data when assessing spatially explicit phenomena such as land-cover change and challenge the usefulness of large-scale (coarse grain, broad extent) studies for understanding social-ecological dynamics around protected areas. © 2016 Society for Conservation Biology.

Hydrological response to land cover changes and human activities in arid regions using a geographic information system and remote sensing.

Directory of Open Access Journals (Sweden)

Shereif H Mahmoud

Full Text Available The hydrological response to land cover changes induced by human activities in arid regions has attracted increased research interest in recent decades. The study reported herein assessed the spatial and quantitative changes in surface runoff resulting from land cover change in the Al-Baha region of Saudi Arabia between 1990 and 2000 using an ArcGIS-surface runoff model and predicted land cover and surface runoff depth in 2030 using Markov chain analysis. Land cover maps for 1990 and 2000 were derived from satellite images using ArcGIS 10.1. The findings reveal a 26% decrease in forest and shrubland area, 28% increase in irrigated cropland, 1.5% increase in sparsely vegetated land and 0.5% increase in bare soil between 1990 and 2000. Overall, land cover changes resulted in a significant decrease in runoff depth values in most of the region. The decrease in surface runoff depth ranged from 25-106 mm/year in a 7020-km2 area, whereas the increase in such depth reached only 10 mm/year in a 243-km2 area. A maximum increase of 73 mm/year was seen in a limited area. The surface runoff depth decreased to the greatest extent in the central region of the study area due to the huge transition in land cover classes associated with the construction of 25 rainwater harvesting dams. The land cover prediction revealed a greater than twofold increase in irrigated cropland during the 2000-2030 period, whereas forest and shrubland are anticipated to occupy just 225 km2 of land area by 2030, a significant decrease from the 747 km2 they occupied in 2000. Overall, changes in land cover are predicted to result in an annual increase in irrigated cropland and dramatic decline in forest area in the study area over the next few decades. The increase in surface runoff depth is likely to have significant implications for irrigation activities.

Variability and trends in the Arctic Sea ice cover: Results from different techniques

Science.gov (United States)

Comiso, Josefino C.; Meier, Walter N.; Gersten, Robert

2017-08-01

Variability and trend studies of sea ice in the Arctic have been conducted using products derived from the same raw passive microwave data but by different groups using different algorithms. This study provides consistency assessment of four of the leading products, namely, Goddard Bootstrap (SB2), Goddard NASA Team (NT1), EUMETSAT Ocean and Sea Ice Satellite Application Facility (OSI-SAF 1.2), and Hadley HadISST 2.2 data in evaluating variability and trends in the Arctic sea ice cover. All four provide generally similar ice patterns but significant disagreements in ice concentration distributions especially in the marginal ice zone and adjacent regions in winter and meltponded areas in summer. The discrepancies are primarily due to different ways the four techniques account for occurrences of new ice and meltponding. However, results show that the different products generally provide consistent and similar representation of the state of the Arctic sea ice cover. Hadley and NT1 data usually provide the highest and lowest monthly ice extents, respectively. The Hadley data also show the lowest trends in ice extent and ice area at -3.88%/decade and -4.37%/decade, respectively, compared to an average of -4.36%/decade and -4.57%/decade for all four. Trend maps also show similar spatial distribution for all four with the largest negative trends occurring at the Kara/Barents Sea and Beaufort Sea regions, where sea ice has been retreating the fastest. The good agreement of the trends especially with updated data provides strong confidence in the quantification of the rate of decline in the Arctic sea ice cover.Plain Language SummaryThe declining Arctic sea ice cover, especially in the summer, has been the center of attention in recent years. Reports on the sea ice cover have been provided by different institutions using basically the same set of satellite data but different techniques for estimating key parameters such as ice concentration, ice extent, and ice area. In

Evaporation suppression from water reservoirs using floating covers: Lab scale observations and model predictions

Science.gov (United States)

Or, D.; Lehmann, P.; Aminzadeh, M.; Sommer, M.; Wey, H.; Wunderli, H.; Breitenstein, D.

2016-12-01

The competition over dwindling fresh water resources is expected to intensify with projected increase in human population in arid regions, expansion of irrigated land and changes in climate and drought patterns. The volume of water stored in reservoirs would also increase to mitigate seasonal shortages due to rainfall variability and to meet irrigation water needs. By some estimates up to half of the stored water is lost to evaporation thereby exacerbating the water scarcity problem. Recently, there is an upsurge in the use of self-assembling floating covers to suppress evaporation, yet the design, and implementation remain largely empirical. Studies have shown that evaporation suppression is highly nonlinear, as also known from a century of research on gas exchange from plant leaves (that often evaporate as free water surfaces through stomata that are only 1% of leaf area). We report a systematic evaluation of different cover types and external drivers (radiation, wind, wind+radiation) on evaporation suppression and energy balance of a 1.4 m2 basin placed in a wind-tunnel. Surprisingly, evaporation suppression by black and white floating covers (balls and plates) were similar despite significantly different energy balance regimes over the cover surfaces. Moreover, the evaporation suppression efficiency was a simple function of the uncovered area (square root of the uncovered fraction) with linear relations with the covered area in some cases. The thermally decoupled floating covers offer an efficient solution to the evaporation suppression with limited influence of the surface energy balance (water temperature for black and white covers was similar and remained nearly constant). The results will be linked with a predictive evaporation-energy balance model and issues of spatial scales and long exposure times will be studied.

Palliation of malignant gastric obstruction : fluoroscopic guided covered metallic stent placement

International Nuclear Information System (INIS)

Lee, Jeong Min; Han, Young Min; Kim, Chong Soo; Lee, Sang Yong; Choi, Ki Chul; Lee, Soo Tak; Han, Hyun Young

2000-01-01

To demonstrate the feasibility and clinical efficacy of self-expanding, covered metallic stent placement for the palliative treatment of malignant gastric obstruction. Under fluoroscopic guidance, the placement of self-expanding, covered stents was attempted in 23 patients (age range, 31-78 years) with inoperable or recurrent gastric malignancies. All 23 suffered dysphagia and/or vomiting after the ingestion of soft foods, or swallowing difficulty. Three different types of self-expanding, covered metallic stents were used and in all patients, these were placed perorally using over the guide wire technique. Success was defined both technically and clinically. Stent placement was technically successful in 19 patients (82.6%) but because the guidewire failed to successfully negotiate the sites at which there was obstruction, was unsuccessful in four (17.4%). Stent placement was well tolerated in all patients except one, in whom an acutely angled efferent loop from remnant stomach was present. In this case, stent placement required a strong metallic guidewire. After placement, 17 of the 19 patients (89.5%) were able to ingest solid and/or soft foods without dysphagia and showed a markedly decreased incidence of vomiting. Two others showed some improvement in the frequency of vomiting but were able to ingest only a liquid diet. In one patient, the stent migrated two days after the procedure. During the follow-up period of 2-7 months (mean, 74 days), there were no clinically significant complications. For the short-term palliative treatment of patients with gastric inlet or outlet obstruction, the placement of self-expanding metallic stents has proven relatively easy and safe, as well as reasonably effective. (author)

Snow Cover Maps from MODIS Images at 250 m Resolution, Part 2: Validation

Directory of Open Access Journals (Sweden)

Marc Zebisch

2013-03-01

Full Text Available The performance of a new algorithm for binary snow cover monitoring based on Moderate Resolution Imaging Spectroradiometer (MODIS satellite images at 250 m resolution is validated using snow cover maps (SCA based on Landsat 7 ETM+ images and in situ snow depth measurements from ground stations in selected test sites in Central Europe. The advantages of the proposed algorithm are the improved ground resolution of 250 m and the near real-time availability with respect to the 500 m standard National Aeronautics and Space Administration (NASA MODIS snow products (MOD10 and MYD10. It allows a more accurate snow cover monitoring at a local scale, especially in mountainous areas characterized by large landscape heterogeneity. The near real-time delivery makes the product valuable as input for hydrological models, e.g., for flood forecast. A comparison to sixteen snow cover maps derived from Landsat ETM/ETM+ showed an overall accuracy of 88.1%, which increases to 93.6% in areas outside of forests. A comparison of the SCA derived from the proposed algorithm with standard MODIS products, MYD10 and MOD10, indicates an agreement of around 85.4% with major discrepancies in forested areas. The validation of MODIS snow cover maps with 148 in situ snow depth measurements shows an accuracy ranging from 94% to around 82%, where the lowest accuracies is found in very rugged terrain restricted to in situ stations along north facing slopes, which lie in shadow in winter during the early morning acquisition.

Case report: ruptured aortic aneurysm into oesophagus - treatment by covered stent

International Nuclear Information System (INIS)

Young, N.; Tan, I.; Costa, R.

2002-01-01

Full text: A case report of a 70 year old man acutely presenting with a large descending thoracic aortic aneurysm, ruptured into the adjacent oesophagus. He was treated with an Aneurex covered stent (Medtronics). This patient has a long history of ischaemic heart disease, hypertension and previously treated abdominal aortic aneurysm. After diagnosis by CT, the bleeding was emergency temponaded by insertion of a Sengstaken-Blackmore tube into the oesophagus and inflated to arterial pressure. After stabilisation in ICU, it was decided that open surgery would probably prove fatal, and insertion of a covered thoracic aortic stent was performed in theatre with a femoral artery cut-down. Post-operatively the bleeding from the aortic aneurysm ceased. However, the patient has ongoing problems with large, open oesophageal ulcer with chronic ooze requiring intermittent transfusions, chronic infection with MRSA, requiring long term antibiotics, feeding via feeding gastrostomy tubes. The patient is stable 12 months after presentation. Treatment of this otherwise fatal problem by covered stent has permitted survival benefit. However, there are significant, unresolved issues of oesophageal ulcer and ongoing MRSA infection. Copyright (2002) Blackwell Science Pty Ltd

Mapping ground cover using hyperspectral remote sensing after the 2003 Simi and Old wildfires in southern California

Science.gov (United States)

Sarah A. Lewis; Leigh B. Lentile; Andrew T. Hudak; Peter R. Robichaud; Penelope Morgan; Michael J. Bobbitt

2007-01-01

Wildfire effects on the ground surface are indicative of the potential for post-fire watershed erosion response. Areas with remaining organic ground cover will likely experience less erosion than areas of complete ground cover combustion or exposed mineral soil. The Simi and Old fires burned ~67,000 ha in southern California in 2003. Burn severity indices calculated...

The Influence of Garden Size and Floral Cover on Pollen Deposition in Urban Community Gardens

Directory of Open Access Journals (Sweden)

Kevin C. Matteson

2009-01-01

Full Text Available Many cucurbits, such as cucumbers, squashes and pumpkins, depend on pollinating bees in order to set fruit. However, fruit yield and progeny vigor in these plants generally decreases as heterospecific pollen deposition increases. We studied how the spatial area dedicated to cucumbers (Cucumis sativis, versus other flowering plants, influenced the deposition of conspecific and heterospecific pollen on cucumber plants in New York City community gardens. We also examined the effect of garden size on conspecific and heterospecific pollen deposition on cucumber plants. Female flowers were collected from potted cucumber plants that had been experimentally placed into the gardens, specifically for this study, or that were established in raised beds by members of the community garden. In the laboratory, pollen grains were isolated from the flower by acetolysis, and the number of heterospecific and conspecific cucumber pollen grains were quantified. Conspecific pollen deposition was positively and significantly associated with the size of a community garden, as well as with the area of each garden dedicated to non-cucumber, flowering plants (i.e. floral cover and the area of each garden dedicated to cucumber plants (i.e. cucumber cover. Although floral cover explained a greater proportion of the variance, cucumber cover had the strongest effect on conspecific pollen deposition. Heterospecific pollen deposition was positively and significantly related to garden area. However, no significant relationship was found between heterospecific pollen deposition and floral cover, or cucumber cover. Based upon these results, we hypothesize that floral cover positively impacts conspecific pollen deposition by attracting a greater number of pollinators into an urban garden, and that total cucumber area positively impacts conspecific pollen deposition when pollinators are locally foraging within a garden. We suggest that the arrangement of plants within a garden can

Study on mechanics of driving drum with superelastic convexity surface covering-layer structure

Energy Technology Data Exchange (ETDEWEB)

Xiao, L.J.; Sui, X.H.; Miao, D.J. [Shandong University of Science & Technology, Qingdao (China)

2008-09-15

Belt conveyor is one of the main transport equipment in coal mine and the driving drum is its key part. With the method of bionic design, the mushroom morphological structure is applied to the design of covering-layer structure of driving drum surface of belt conveyor. Superelastic rubber with large deformation is adopted as the covering-layer material. Nonlinear constitutive model of rubber, which is of superelasticity and large deformation, is established. The stress states and deformation principles of driving drums including both bionic covering-layer and common covering-layer are obtained by static intensity analysis with Finite Element Analysis (FEA) software ANSYS. The values of the stress and strain on the driving drum surface are gotten and the dangerous area is determined. FEA results show that the superelastic convexity surface structure can enlarge the contact area between the driving drum and viscoelastic belt. The results also show that in comparison with common driving drum, the bionic surface driving drum can not only increase the friction coefficient between drum and belt but also prolong its service life.

Recent tree cover increases in eastern China linked to low, declining human pressure, steep topography, and climatic conditions favoring tree growth.

Directory of Open Access Journals (Sweden)

Jonas Nüchel

Full Text Available Globally, the extent of forest continues to decline, however, some countries have increased their forest extent in recent years. China is one of these countries and has managed to increase their tree cover through huge reforestation and afforestation programs during recent decades as well as land abandonment dynamics. This study investigates tree cover change in the eastern half of China between 2000 and 2010 on three different scales, using random forest modeling of remote sensing data for tree cover in relation to environmental and anthropogenic predictor variables. Our results show that between the years 2000 and 2010 2,667,875 km2 experienced an increase in tree cover while 1,854,900 km2 experienced a decline in tree cover. The area experiencing ≥10% increase in tree cover is almost twice as large as the area with ≥10% drop in tree cover. There is a clear relation between topography and tree cover change with steeper and mid-elevation areas having a larger response on tree cover increase than other areas. Furthermore, human influence, change in population density, and actual evapotranspiration are also important factors in explaining where tree cover has changed. This study adds to the understanding of tree cover change in China, as it has focus on the entire eastern half of China on three different scales and how tree cover change is linked to topography and anthropogenic pressure. Though, our results show an increase in tree cover in China, this study emphasizes the importance of incorporating anthropogenic factors together with biodiversity protection into the reforestation and afforestation programs in the future.

Recent tree cover increases in eastern China linked to low, declining human pressure, steep topography, and climatic conditions favoring tree growth.

Science.gov (United States)

Nüchel, Jonas; Svenning, Jens-Christian

2017-01-01

Globally, the extent of forest continues to decline, however, some countries have increased their forest extent in recent years. China is one of these countries and has managed to increase their tree cover through huge reforestation and afforestation programs during recent decades as well as land abandonment dynamics. This study investigates tree cover change in the eastern half of China between 2000 and 2010 on three different scales, using random forest modeling of remote sensing data for tree cover in relation to environmental and anthropogenic predictor variables. Our results show that between the years 2000 and 2010 2,667,875 km2 experienced an increase in tree cover while 1,854,900 km2 experienced a decline in tree cover. The area experiencing ≥10% increase in tree cover is almost twice as large as the area with ≥10% drop in tree cover. There is a clear relation between topography and tree cover change with steeper and mid-elevation areas having a larger response on tree cover increase than other areas. Furthermore, human influence, change in population density, and actual evapotranspiration are also important factors in explaining where tree cover has changed. This study adds to the understanding of tree cover change in China, as it has focus on the entire eastern half of China on three different scales and how tree cover change is linked to topography and anthropogenic pressure. Though, our results show an increase in tree cover in China, this study emphasizes the importance of incorporating anthropogenic factors together with biodiversity protection into the reforestation and afforestation programs in the future.

Acromegaly Is More Severe in Patients With AHR or AIP Gene Variants Living in Highly Polluted Areas.

Science.gov (United States)

Cannavo, S; Ragonese, M; Puglisi, S; Romeo, P D; Torre, M L; Alibrandi, A; Scaroni, C; Occhi, G; Ceccato, F; Regazzo, D; De Menis, E; Sartorato, P; Arnaldi, G; Trementino, L; Trimarchi, F; Ferrau, F

2016-04-01

An increased prevalence of acromegaly was found some years ago in a highly polluted area in North-Eastern Sicily, where high concentration of nonmethane hydrocarbons, volatile organic compounds, and cadmium was found. Aryl hydrocarbon receptor (AHR) pathway has a key role in detoxification of these compounds and in tumorigenesis. We correlated the occurrence of AHR and/or AHR-interacting protein (AIP) gene variants with acromegaly severity according to pollution exposition. This was an observational, perspective study conducted over 7 years in four Italian referral centers for pituitary diseases in which 210 patients with acromegaly were enrolled between 2008 and 2015. Genetic screening of patients for AHR and AIP variants. Clinical, biochemical, and radiological data of patients with and without AIP and/or AHR gene variants, living in polluted (high-risk for health, [HR]) or nonpolluted (NP) areas of five Italian regions were evaluated and compared. Among the 23 patients from HR areas, nine showed AHR or AIP variants. Mean IGF-I levels and pituitary tumor diameter were significantly higher in these nine patients (HR/VAR+) than in the other 14 (HR/VAR−) and in the 187 from NP areas (44 NP/VAR+). Somatostatin analogs significantly decreased mean GH and IGF-I levels in patients from NP areas and in HR/VAR− (GH P acromegaly, increased pituitary tumor size, and somatostatin analog resistance in patients living in HR areas.

Using remote sensing imagery and GIS to identify land cover and land use within Ceahlau Massif (Romania

Directory of Open Access Journals (Sweden)

GEORGE CRACU

2014-11-01

Full Text Available Using remote sensing imagery and GIS to identify land cover and land use within Ceahlău Massif (Romania. In this study we considerer land cover and land use asessment within Ceahlău Massif (Romania using satellite imagery and GIS . To achieve this goal, we used a Landsat 7 ETM + satellite image, which was processed using specialized software in analyzing satellite images and GIS software in several stages:  Downloading, importing and layer stack of all spectral bands composing satellite image;  Establishment of areas of interest for each category of land cover and land use, which were digitized on - screen and for which spectral signatures characteristics were established;  Supervised image classification using Maximum Likelihood Method;  Importing the resulting m ap (raster in GIS environment and creating the final land cover/land use map for Ceahlău Massif. In the study area we identified nine land cover/land use classes: deciduous forests, mixed forests, coniferous forests, secondary grasslands, subalpine vegeta tion, alpine meadows, agricultural land, lakes and built area. By analizing the spatial distribution of these classes, it was found that forests are the best represented class, occupying an area of 188.4 km² (56.4% of total, followed by secondary grassl and, which occupies an area of 68.2 km² (20.4% of total, lakes (26.6 km² or 7.98% of total and agricultural land (16.1 km² or 4.86%

Texture classification of vegetation cover in high altitude wetlands zone

International Nuclear Information System (INIS)

Wentao, Zou; Bingfang, Wu; Hongbo, Ju; Hua, Liu

2014-01-01

The aim of this study was to investigate the utility of datasets composed of texture measures and other features for the classification of vegetation cover, specifically wetlands. QUEST decision tree classifier was applied to a SPOT-5 image sub-scene covering the typical wetlands area in Three River Sources region in Qinghai province, China. The dataset used for the classification comprised of: (1) spectral data and the components of principal component analysis; (2) texture measures derived from pixel basis; (3) DEM and other ancillary data covering the research area. Image textures is an important characteristic of remote sensing images; it can represent spatial variations with spectral brightness in digital numbers. When the spectral information is not enough to separate the different land covers, the texture information can be used to increase the classification accuracy. The texture measures used in this study were calculated from GLCM (Gray level Co-occurrence Matrix); eight frequently used measures were chosen to conduct the classification procedure. The results showed that variance, mean and entropy calculated by GLCM with a 9*9 size window were effective in distinguishing different vegetation types in wetlands zone. The overall accuracy of this method was 84.19% and the Kappa coefficient was 0.8261. The result indicated that the introduction of texture measures can improve the overall accuracy by 12.05% and the overall kappa coefficient by 0.1407 compared with the result using spectral and ancillary data

Runoff estimation in residencial area

Directory of Open Access Journals (Sweden)

Meire Regina de Almeida Siqueira

2013-12-01

Full Text Available This study aimed to estimate the watershed runoff caused by extreme events that often result in the flooding of urban areas. The runoff of a residential area in the city of Guaratinguetá, São Paulo, Brazil was estimated using the Curve-Number method proposed by USDA-NRCS. The study also investigated current land use and land cover conditions, impermeable areas with pasture and indications of the reforestation of those areas. Maps and satellite images of Residential Riverside I Neighborhood were used to characterize the area. In addition to characterizing land use and land cover, the definition of the soil type infiltration capacity, the maximum local rainfall, and the type and quality of the drainage system were also investigated. The study showed that this neighborhood, developed in 1974, has an area of 792,700 m², a population of 1361 inhabitants, and a sloping area covered with degraded pasture (Guaratinguetá-Piagui Peak located in front of the residential area. The residential area is located in a flat area near the Paraiba do Sul River, and has a poor drainage system with concrete pipes, mostly 0.60 m in diameter, with several openings that capture water and sediments from the adjacent sloping area. The Low Impact Development (LID system appears to be a viable solution for this neighborhood drainage system. It can be concluded that the drainage system of the Guaratinguetá Riverside I Neighborhood has all of the conditions and characteristics that make it suitable for the implementation of a low impact urban drainage system. Reforestation of Guaratinguetá-Piagui Peak can reduce the basin’s runoff by 50% and minimize flooding problems in the Beira Rio neighborhood.

Cortical thickness and surface area correlates with cognitive dysfunction among first-episode psychosis patients.

Science.gov (United States)

Haring, L; Müürsepp, A; Mõttus, R; Ilves, P; Koch, K; Uppin, K; Tarnovskaja, J; Maron, E; Zharkovsky, A; Vasar, E; Vasar, V

2016-07-01

In studies using magnetic resonance imaging (MRI), some have reported specific brain structure-function relationships among first-episode psychosis (FEP) patients, but findings are inconsistent. We aimed to localize the brain regions where cortical thickness (CTh) and surface area (cortical area; CA) relate to neurocognition, by performing an MRI on participants and measuring their neurocognitive performance using the Cambridge Neuropsychological Test Automated Battery (CANTAB), in order to investigate any significant differences between FEP patients and control subjects (CS). Exploration of potential correlations between specific cognitive functions and brain structure was performed using CANTAB computer-based neurocognitive testing and a vertex-by-vertex whole-brain MRI analysis of 63 FEP patients and 30 CS. Significant correlations were found between cortical parameters in the frontal, temporal, cingular and occipital brain regions and performance in set-shifting, working memory manipulation, strategy usage and sustained attention tests. These correlations were significantly dissimilar between FEP patients and CS. Significant correlations between CTh and CA with neurocognitive performance were localized in brain areas known to be involved in cognition. The results also suggested a disrupted structure-function relationship in FEP patients compared with CS.

Deriving a per-field land use and land cover map in an agricultural mosaic catchment

Science.gov (United States)

Seo, B.; Bogner, C.; Poppenborg, P.; Martin, E.; Hoffmeister, M.; Jun, M.; Koellner, T.; Reineking, B.; Shope, C. L.; Tenhunen, J.

2014-09-01

Detailed data on land use and land cover constitute important information for Earth system models, environmental monitoring and ecosystem services research. Global land cover products are evolving rapidly; however, there is still a lack of information particularly for heterogeneous agricultural landscapes. We censused land use and land cover field by field in the agricultural mosaic catchment Haean in South Korea. We recorded the land cover types with additional information on agricultural practice. In this paper we introduce the data, their collection and the post-processing protocol. Furthermore, because it is important to quantitatively evaluate available land use and land cover products, we compared our data with the MODIS Land Cover Type product (MCD12Q1). During the studied period, a large portion of dry fields was converted to perennial crops. Compared to our data, the forested area was underrepresented and the agricultural area overrepresented in MCD12Q1. In addition, linear landscape elements such as waterbodies were missing in the MODIS product due to its coarse spatial resolution. The data presented here can be useful for earth science and ecosystem services research. The data are available at the public repository Pangaea (doi:110.1594/PANGAEA.823677).

Branched polynomial covering maps

DEFF Research Database (Denmark)

Hansen, Vagn Lundsgaard

2002-01-01

A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch ...... set. Particular studies are made of branched polynomial covering maps arising from Riemann surfaces and from knots in the 3-sphere. (C) 2001 Elsevier Science B.V. All rights reserved.......A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...

Inducing Water Productivity from Snow Cover for Sustainable Water Management in Ibrahim River Basin, Lebanon

OpenAIRE

Darwish , Talal; SHABAN , Amin; Portoghese , Ivan; Vurro , Michele; Khadra , Roula; Saqallah , Sagedah; Drapeau , Laurent; Gascoin , Simon; Amacha , Nabil

2015-01-01

International audience; The aim of this paper is to explore the effects and linkages between snow cover areas, distribution, probability and measured water discharge along east Mediterranean coastal watershed using moderate-resolution satellite images (MODIS-Terra). The Nahr Ibrahim River is a typical Lebanese watershed with an area of 326 km2 stretching between the sea and mountainous terrain to the east. The largest snow cover often exists in January-February with snow-free conditions betwe...

Effect of landslides on the structural characteristics of land-cover based on complex networks

Science.gov (United States)

He, Jing; Tang, Chuan; Liu, Gang; Li, Weile

2017-09-01

Landslides have been widely studied by geologists. However, previous studies mainly focused on the formation of landslides and never considered the effect of landslides on the structural characteristics of land-cover. Here we define the modeling of the graph topology for the land-cover, using the satellite images of the earth’s surface before and after the earthquake. We find that the land-cover network satisfies the power-law distribution, whether the land-cover contains landslides or not. However, landslides may change some parameters or measures of the structural characteristics of land-cover. The results show that the linear coefficient, modularity and area distribution are all changed after the occurence of landslides, which means the structural characteristics of the land-cover are changed.

Identifying the Relationships between Water Quality and Land Cover Changes in the Tseng-Wen Reservoir Watershed of Taiwan

Directory of Open Access Journals (Sweden)

Hone-Jay Chu

2013-01-01

Full Text Available The effects on water quality of land use and land cover changes, which are associated with human activities and natural factors, are poorly identified. Fine resolution satellite imagery provides opportunities for land cover monitoring and assessment. The multiple satellite images after typhoon events collected from 2001 to 2010 covering land areas and land cover conditions are evaluated by the Normalized Difference Vegetation Index (NDVI. The relationship between land cover and observed water quality, such as suspended solids (SS and nitrate-nitrogens (NO3-N, are explored in the study area. Results show that the long-term variations in water quality are explained by NDVI data in the reservoir buffer zones. Suspended solid and nitrate concentrations are related to average NDVI values on multiple spatial scales. Annual NO3-N concentrations are positively correlated with an average NDVI with a 1 km reservoir buffer area, and the SS after typhoon events associated with landslides are negatively correlated with the average NDVI in the entire watershed. This study provides an approach for assessing the influences of land cover on variations in water quality.

Albedo of the ice covered Weddell and Bellingshausen Seas

OpenAIRE

A. I. Weiss; J. C. King; T. A. Lachlan-Cope; R. S. Ladkin

2012-01-01

This study investigates the surface albedo of the sea ice areas adjacent to the Antarctic Peninsula during the austral summer. Aircraft measurements of the surface albedo, which were conducted in the sea ice areas of the Weddell and Bellingshausen Seas show significant differences between these two regions. The averaged surface albedo varied between 0.13 and 0.81. The ice cover of the Bellingshausen Sea consisted mainly of first year ice and the sea surface showed an averaged sea ice albedo o...

Albedo of the ice-covered Weddell and Bellingshausen Sea

OpenAIRE

A. I. Weiss; J. C. King; T. A. Lachlan-Cope; R. S. Ladkin

2011-01-01

This study investigates the surface albedo of the sea ice areas adjacent to the Antarctic Peninsula during the austral summer. Aircraft measurements of the surface albedo which were conducted in the sea ice areas of the Weddell and Bellingshausen Sea show significant differences between these two regions. The averaged surface albedo varied between 0.13 and 0.81. The ice cover of the Bellingshausen Sea consisted mainly of first year ice and the sea surface showed an averaged sea ice albed...

Forest Cover Mapping in Iskandar Malaysia Using Satellite Data

Science.gov (United States)

Kanniah, K. D.; Mohd Najib, N. E.; Vu, T. T.

2016-09-01

Malaysia is the third largest country in the world that had lost forest cover. Therefore, timely information on forest cover is required to help the government to ensure that the remaining forest resources are managed in a sustainable manner. This study aims to map and detect changes of forest cover (deforestation and disturbance) in Iskandar Malaysia region in the south of Peninsular Malaysia between years 1990 and 2010 using Landsat satellite images. The Carnegie Landsat Analysis System-Lite (CLASlite) programme was used to classify forest cover using Landsat images. This software is able to mask out clouds, cloud shadows, terrain shadows, and water bodies and atmospherically correct the images using 6S radiative transfer model. An Automated Monte Carlo Unmixing technique embedded in CLASlite was used to unmix each Landsat pixel into fractions of photosynthetic vegetation (PV), non photosynthetic vegetation (NPV) and soil surface (S). Forest and non-forest areas were produced from the fractional cover images using appropriate threshold values of PV, NPV and S. CLASlite software was found to be able to classify forest cover in Iskandar Malaysia with only a difference between 14% (1990) and 5% (2010) compared to the forest land use map produced by the Department of Agriculture, Malaysia. Nevertheless, the CLASlite automated software used in this study was found not to exclude other vegetation types especially rubber and oil palm that has similar reflectance to forest. Currently rubber and oil palm were discriminated from forest manually using land use maps. Therefore, CLASlite algorithm needs further adjustment to exclude these vegetation and classify only forest cover.

Mekong Land Cover Dasboard: Regional Land Cover Mointoring Systems

Science.gov (United States)

Saah, D. S.; Towashiraporn, P.; Aekakkararungroj, A.; Phongsapan, K.; Triepke, J.; Maus, P.; Tenneson, K.; Cutter, P. G.; Ganz, D.; Anderson, E.

2016-12-01

SERVIR-Mekong, a USAID-NASA partnership, helps decision makers in the Lower Mekong Region utilize GIS and Remote Sensing information to inform climate related activities. In 2015, SERVIR-Mekong conducted a geospatial needs assessment for the Lower Mekong countries which included individual country consultations. The team found that many countries were dependent on land cover and land use maps for land resource planning, quantifying ecosystem services, including resilience to climate change, biodiversity conservation, and other critical social issues. Many of the Lower Mekong countries have developed national scale land cover maps derived in part from remote sensing products and geospatial technologies. However, updates are infrequent and classification systems do not always meet the needs of key user groups. In addition, data products stop at political boundaries and are often not accessible making the data unusable across country boundaries and with resource management partners. Many of these countries rely on global land cover products to fill the gaps of their national efforts, compromising consistency between data and policies. These gaps in national efforts can be filled by a flexible regional land cover monitoring system that is co-developed by regional partners with the specific intention of meeting national transboundary needs, for example including consistent forest definitions in transboundary watersheds. Based on these facts, key regional stakeholders identified a need for a land cover monitoring system that will produce frequent, high quality land cover maps using a consistent regional classification scheme that is compatible with national country needs. SERVIR-Mekong is currently developing a solution that leverages recent developments in remote sensing science and technology, such as Google Earth Engine (GEE), and working together with production partners to develop a system that will use a common set of input data sources to generate high

Hepatitis C virus sequences from different patients confirm the existence and transmissibility of subtype 2q, a rare subtype circulating in the metropolitan area of Barcelona, Spain.

Science.gov (United States)

Martró, Elisa; Valero, Ana; Jordana-Lluch, Elena; Saludes, Verónica; Planas, Ramón; González-Candelas, Fernando; Ausina, Vicente; Bracho, Maria Alma

2011-05-01

The hepatitis C virus (HCV) has been classified into six genotypes and more than 70 subtypes with distinct geographical and epidemiological distributions. While 18 genotype 2 subtypes have been proposed, only 5 have had their complete sequence determined. The aim of this study was to characterize HCV isolates from three patients from the Barcelona metropolitan area of Spain for whom commercial genotyping methods provided discordant results. Full-length genome sequencing was carried out for 2 of the 3 patients; for the third patient only partial NS5B sequences could be obtained. The generated sequences were subjected to phylogenetic, recombination, and identity analyses. Sequences covering most of the HCV genome (9398 and 9566  nt in length) were obtained and showed a 90.3% identity to each other at the nucleotide level, while both sequences differed by 17.5-22.6% from the other fully sequenced genotype 2 subtypes. No evidence of recombination was found. The NS5B phylogenetic tree showed that sequences from the three patients cluster together with the only representative sequence of the provisionally designed 2q subtype, which also corresponds to a patient from Barcelona. Phylogenetic analysis of the full coding sequence showed that subtype 2q was more closely related to subtype 2k. The results obtained in this study suggest that subtype 2q now meets the requirements for confirmed designation status according to consensus criteria for HCV classification and nomenclature, and its epidemiological value is ensured as it has spread among several patients in the Barcelona metropolitan area. Copyright © 2011 Wiley-Liss, Inc.

Treatment of traumatic internal carotid artery pseudoaneurysms with willis covered stents: a midterm follow-up result

International Nuclear Information System (INIS)

Wang Wu; Li Minghua; Li Yongdong; Gu Binxian; Fang Chun; Tan Huaqiao; Wang Ju; Zhang Peilei

2010-01-01

Objective: To evaluate the efficacy and mid-term follow-up results of endovascular treatment with Willis covered stent for traumatic pseudoaneurysms located in the internal carotid artery (ICA). Methods: ICA angiography was performed in 38 patients with traumatic brain and neck injury. Of the 38 patients, 13 delayed traumatic pseudoaneurysms were found. All the pseudoaneurysms were treated with Willis covered stents. Follow-up angiography was performed at 1, 3, 6 and 12 months after the procedure, and the results were categorized as complete or incomplete occlusion. Clinical manifestations were graded as full recovery, improvement, unchanged and aggravation. Results: Willis covered stent placement was technically successful in all traumatic pseudoaneurysms. No procedure-related complications occurred. The initial angiographic results showed a complete occlusion in 9 patients, and an incomplete occlusion in 4. The angiographic follow-up within 3-12 months exhibited a complete occlusion in 12 patients and the parent arteries remained patency in all patients. The clinical follow-up observation demonstrated that full recovery was obtained in 11 patients, clinical improvement in one, and unchanged condition in one. No morbidity or mortality occurred. Conclusion: Willis covered stent implantation is a feasible and practical treatment for traumatic pseudoaneurysms located in the ICA. This technique can well preserve the parent artery with excellent therapeutic results. (authors)

Land cover mapping of North and Central America—Global Land Cover 2000

Science.gov (United States)

Latifovic, Rasim; Zhu, Zhi-Liang

2004-01-01

The Land Cover Map of North and Central America for the year 2000 (GLC 2000-NCA), prepared by NRCan/CCRS and USGS/EROS Data Centre (EDC) as a regional component of the Global Land Cover 2000 project, is the subject of this paper. A new mapping approach for transforming satellite observations acquired by the SPOT4/VGTETATION (VGT) sensor into land cover information is outlined. The procedure includes: (1) conversion of daily data into 10-day composite; (2) post-seasonal correction and refinement of apparent surface reflectance in 10-day composite images; and (3) extraction of land cover information from the composite images. The pre-processing and mosaicking techniques developed and used in this study proved to be very effective in removing cloud contamination, BRDF effects, and noise in Short Wave Infra-Red (SWIR). The GLC 2000-NCA land cover map is provided as a regional product with 28 land cover classes based on modified Federal Geographic Data Committee/Vegetation Classification Standard (FGDC NVCS) classification system, and as part of a global product with 22 land cover classes based on Land Cover Classification System (LCCS) of the Food and Agriculture Organisation. The map was compared on both areal and per-pixel bases over North and Central America to the International Geosphere–Biosphere Programme (IGBP) global land cover classification, the University of Maryland global land cover classification (UMd) and the Moderate Resolution Imaging Spectroradiometer (MODIS) Global land cover classification produced by Boston University (BU). There was good agreement (79%) on the spatial distribution and areal extent of forest between GLC 2000-NCA and the other maps, however, GLC 2000-NCA provides additional information on the spatial distribution of forest types. The GLC 2000-NCA map was produced at the continental level incorporating specific needs of the region.

Land Use and Land Cover (LULC) Change Detection in Islamabad and its Comparison with Capital Development Authority (CDA) 2006 Master Plan

Science.gov (United States)

Hasaan, Zahra

2016-07-01

Remote sensing is very useful for the production of land use and land cover statistics which can be beneficial to determine the distribution of land uses. Using remote sensing techniques to develop land use classification mapping is a convenient and detailed way to improve the selection of areas designed to agricultural, urban and/or industrial areas of a region. In Islamabad city and surrounding the land use has been changing, every day new developments (urban, industrial, commercial and agricultural) are emerging leading to decrease in vegetation cover. The purpose of this work was to develop the land use of Islamabad and its surrounding area that is an important natural resource. For this work the eCognition Developer 64 computer software was used to develop a land use classification using SPOT 5 image of year 2012. For image processing object-based classification technique was used and important land use features i.e. Vegetation cover, barren land, impervious surface, built up area and water bodies were extracted on the basis of object variation and compared the results with the CDA Master Plan. The great increase was found in built-up area and impervious surface area. On the other hand vegetation cover and barren area followed a declining trend. Accuracy assessment of classification yielded 92% accuracies of the final land cover land use maps. In addition these improved land cover/land use maps which are produced by remote sensing technique of class definition, meet the growing need of legend standardization.

HIPAA-protecting patient confidentiality or covering something else?

Directory of Open Access Journals (Sweden)

Robbins RA

2013-10-01

Full Text Available No abstract available. Article truncated at 150 words. A case of a physician fired from the Veterans Administration (VA for violation of the Health Care Portability and Accountability Act of 1996 (HIPAA illustrates a problem with both the law and the VA. Anil Parikh, a VA physician at the Jesse Brown VA in Chicago, was dismissed on a charge of making unauthorized disclosures of confidential patient information on October 19, 2007. On January 3, 2011 the Merit Systems Protection Board (MSPB reversed Dr. Parikh’s removal. Dr. Parikh's initially made disclosures to the VA Office of Inspector General and to Senator Barack Obama and Congressman Luis Gutierrez, in whose district the Jesse Brown VA lies. Dr. Parikh alleged that there were systematic problems within the Jesse Brown VA that resulted in untimely and inadequate patient care. The confidential patient information Parikh disclosed included examples of the misdiagnoses and misdirection of patients within the hospital. Specifically, Dr. Parikh alleged that …

Mapping land cover in urban residential landscapes using fine resolution imagery and object-oriented classification

Science.gov (United States)

A knowledge of different types of land cover in urban residential landscapes is important for building social and economic city-wide policies including landscape ordinances and water conservation programs. Urban landscapes are typically heterogeneous, so classification of land cover in these areas ...

Case study of a full-scale evapotranspiration cover

Science.gov (United States)

McGuire, Patrick E.; Andraski, Brian J.; Archibald, Ryan E.

2009-01-01

The design, construction, and performance analyses of a 6.1ha evapotranspiration (ET) landfill cover at the semiarid U.S. Army Fort Carson site, near Colorado Springs, Colo. are presented. Initial water-balance model simulations, using literature reported soil hydraulic data, aided selection of borrow-source soil type(s) that resulted in predictions of negligible annual drainage (⩽1mm∕year). Final construction design was based on refined water-balance simulations using laboratory determined soil hydraulic values from borrow area natural soil horizons that were described with USDA soil classification methods. Cover design components included a 122cmthick clay loam (USDA), compaction ⩽80% of the standard Proctor maximum dry density (dry bulk density ∼1.3Mg∕m3), erosion control measures, top soil amended with biosolids, and seeding with native grasses. Favorable hydrologic performance for a 5year period was documented by lysimeter-measured and Richards’-based calculations of annual drainage that were all <0.4mm∕year. Water potential data suggest that ET removed water that infiltrated the cover and contributed to a persistent driving force for upward flow and removal of water from below the base of the cover.

Assessing the land cover situation in Surkhang, Upper Mustang, Nepal, using an ASTER image

NARCIS (Netherlands)

Sharma, B.D.; Clevers, J.G.P.W.; Graaf, de N.R.; Chapagain, N.R.

2003-01-01

This paper describes the remote sensing technique used to prepare a land cover map of Surkhang, Upper Mustang Nepal. The latest ASTER image (October 2002) and an ASTER DEM were used for the land cover classification. The study was carried out in Surkhang Village Development Committee (area 799 km2)

Land-use change outweighs projected effects of changing rainfall on tree cover in sub-Saharan Africa.

Science.gov (United States)

Aleman, Julie C; Blarquez, Olivier; Staver, Carla A

2016-09-01

Global change will likely affect savanna and forest structure and distributions, with implications for diversity within both biomes. Few studies have examined the impacts of both expected precipitation and land use changes on vegetation structure in the future, despite their likely severity. Here, we modeled tree cover in sub-Saharan Africa, as a proxy for vegetation structure and land cover change, using climatic, edaphic, and anthropic data (R(2)  = 0.97). Projected tree cover for the year 2070, simulated using scenarios that include climate and land use projections, generally decreased, both in forest and savanna, although the directionality of changes varied locally. The main driver of tree cover changes was land use change; the effects of precipitation change were minor by comparison. Interestingly, carbon emissions mitigation via increasing biofuels production resulted in decreases in tree cover, more severe than scenarios with more intense precipitation change, especially within savannas. Evaluation of tree cover change against protected area extent at the WWF Ecoregion scale suggested areas of high biodiversity and ecosystem services concern. Those forests most vulnerable to large decreases in tree cover were also highly protected, potentially buffering the effects of global change. Meanwhile, savannas, especially where they immediately bordered forests (e.g. West and Central Africa), were characterized by a dearth of protected areas, making them highly vulnerable. Savanna must become an explicit policy priority in the face of climate and land use change if conservation and livelihoods are to remain viable into the next century. © 2016 John Wiley & Sons Ltd.

ASSESSING LAND COVER CHANGES CAUSED BY GRANITE QUARRYING USING REMOTE SENSING

Directory of Open Access Journals (Sweden)

R. S. Moeletsi

2017-11-01

Full Text Available Dimension stone quarrying in the area between Rustenburg and Brits in the North West Province of South Africa has been in existence for over 70 decades. The unique characteristics of the granite deposits in South Africa resulted in making the country a global producer of the granite rocks. This led to intensified quarrying activities between Rustenburg and Brits town. However, this surface mining method, has a potential to impact the environment in a negative way causing loss in vegetation, depletion of natural resources, loss of scenic beauty and contamination of surface water resources. To assess the land cover changes caused by granite quarrying activities, remotely sensed data in the form of Landsat images between 1998 and 2015 were used. Supervised classification was used to create maps. Accuracy assessment using Google EarthTM as a reference data yielded an overall accuracy of 78 %. The post classification change detection method was used to assess land cover changes within the granite quarries. Granite quarries increased by 1174.86 ha while formation of quarry lakes increased to 5.3 ha over the 17-year period. Vegetation cover decreased by 1308 ha in area while 18.3 ha bare land was lost during the same period. This study demonstrated the utility of remote sensing to detect changes in land cover within granite quarries.

Spatio-temporal patterns of ptarmigan occupancy relative to shrub cover in the Arctic

Science.gov (United States)

Schmutz, Joel A.

2014-01-01

Rock and willow ptarmigan are abundant herbivores that require shrub habitats in arctic and alpine areas. Shrub expansion is likely to increase winter habitat availability for ptarmigan, which in turn influence shrub architecture and growth through browsing. Despite their ecological role in the Arctic, the distribution and movement patterns of ptarmigan are not well known, particularly in northern Alaska where shrub expansion is occurring. We used multi-season occupancy models to test whether ptarmigan occupancy varied within and among years, and the degree to which colonization and extinction probabilities were related to shrub cover and latitude. Aerial surveys were conducted from March to May in 2011 and April to May 2012 in a 21,230 km2 area in northeastern Alaska. In areas with at least 30 % shrub cover, the probability of colonization by ptarmigan was >0.90, indicating that moderate to extensive patches of shrubs (typically associated with riparian areas) had a high probability of becoming occupied by ptarmigan. Occupancy increased throughout the spring in both years, providing evidence that ptarmigan migrated from southern wintering areas to breeding areas north of the Brooks Range. Occupancy was higher in the moderate snow year than the high snow year, and this was likely due to higher shrub cover in the moderate snow year. Ptarmigan distribution and migration in the Arctic are linked to expanding shrub communities on a wide geographic scale, and these relationships may be shaping ptarmigan population dynamics, as well as rates and patterns of shrub expansion.

Monitoring the performance of an alternative cover using caisson lysimeters

Energy Technology Data Exchange (ETDEWEB)

Waugh, W.J.; Smith, G.M.; Mushovic, P.S.

2004-02-29

The U.S. Department of Energy (DOE) office in Grand Junction, Colorado, and the U.S. Environmental Protection Agency (EPA), Region 8, collaborated on a series of field lysimeter studies to design and monitor the performance of an alternative cover for a uranium mill tailings disposal cell at the Monticello, Utah, Superfund Site. Because groundwater recharge is naturally limited at Monticello in areas with thick loess soils, DOE and EPA chose to design a cover for Monticello using local soils and a native plant community to mimic this natural soilwater balance. Two large drainage lysimeters fabricated of corrugated steel culvert lined with high-density polyethylene were installed to evaluate the hydrological and ecological performance of an alternative cover design constructed in 2000 on the disposal cell. Unlike conventional, lowpermeability designs, this cover relies on (1) the water storage capacity of a 163-cm soil “sponge” layer overlying a sand-and-gravel capillary barrier to retain precipitation while plants are dormant and (2) native vegetation to remove precipitation during the growing season. The sponge layer consists of a clay loam subsoil compacted to 1.65 g/cm2 in one lysimeter and a loam topsoil compacted to 1.45 g/cm2 in the other lysimeter, representing the range of as-built conditions constructed in the nearby disposal cell cover. About 0.1 mm of drainage occurred in both lysimeters during an average precipitation year and before they were planted, an amount well below the EPA target of <3.0 mm/yr. However, the cover with less compacted loam topsoil sponge had a 40% greater water storage capacity than the cover with overly compacted clay loam subsoil sponge. The difference is attributable in part to higher green leaf area and water extraction by plants in the loam topsoil. The lesson learned is that seemingly subtle differences in soil types, sources, and compaction can result in salient differences in performance. Diverse, seeded communities of

Sealing of Airway Fistulas for Metallic Covered Z-type Stents

Directory of Open Access Journals (Sweden)

Hongwu WANG

2011-08-01

Full Text Available Background and objective Treating airway fistulas, including esophagorespiratory fistulas (ERFs, bronchopleural fistulas (BPFs, and tracheomediastinal fistulas (TMFs, is difficult. The aim of this study is to evaluate the safety and clinical efficacy of metallic covered Z-type stents (CZTS for the treatment of airway fistulas through bronchoscopy or fluroscopy. Methods Thirty-eight patients with fistulas between the esophagus, mediastina, and airways (32 ERFs, 5 BPFs, and 1 TMF were retrospectively reviewed after treatment with covered metallic esophageal and airway stents. The fistulas were caused by esophageal (n=26, bronchogenic (n=11, and thyroid (n=1 carcinomas. Results Forty-six fistulas were found in 38 patients. The fistula size ranged from 0.5 cm to 7.0 cm. Forty airway covered metal stents (24 Y-type, 8 L-type, and 8 I-type and 24 esophageal metal stents were placed. Complete responses to the sealing effects of fistulas were noted in 4.3% of all the fistulas, 60.9% showed complete clinical responses, 23.9% showed partial responses, and 10.9% showed no response. An effectivity rate of 89.1% was observed, and the median survival duration of all patients was 5 months. Conclusion The use of CZTS appears to be safe and feasible for the palliative treatment of ERFs, BPFs, and TMFs. Airway stent placement is recommended for patients with ERF. In the event that airway stents fail, esophageal stents should be given. Airway bifurcation stents were observed to be especially suitable for the sealing of fistulas near the trachea carina.

Updating the 2001 National Land Cover Database Impervious Surface Products to 2006 using Landsat imagery change detection methods

Science.gov (United States)

Xian, George; Homer, Collin G.

2010-01-01

A prototype method was developed to update the U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001 to a nominal date of 2006. NLCD 2001 is widely used as a baseline for national land cover and impervious cover conditions. To enable the updating of this database in an optimal manner, methods are designed to be accomplished by individual Landsat scene. Using conservative change thresholds based on land cover classes, areas of change and no-change were segregated from change vectors calculated from normalized Landsat scenes from 2001 and 2006. By sampling from NLCD 2001 impervious surface in unchanged areas, impervious surface predictions were estimated for changed areas within an urban extent defined by a companion land cover classification. Methods were developed and tested for national application across six study sites containing a variety of urban impervious surface. Results show the vast majority of impervious surface change associated with urban development was captured, with overall RMSE from 6.86 to 13.12% for these areas. Changes of urban development density were also evaluated by characterizing the categories of change by percentile for impervious surface. This prototype method provides a relatively low cost, flexible approach to generate updated impervious surface using NLCD 2001 as the baseline.

Sow preferences for farrowing under a cover with and without access to straw

DEFF Research Database (Denmark)

Damm, Birgitte Iversen; Heiskanen, Teresia; Pedersen, Lene Juul

2010-01-01

and thus piglet survival we investigated if access to a covered area and ad libitum access to straw would improve maternal behaviour of importance for piglet survival. We used forty-four primiparous sows housed in large individual pens from approximately 2 weeks prior to expected parturition. The sows were...... and the temporal pattern of sow position in relation to position of the cover (left or right side of the pen) was studied. Furthermore, postural and nest-building behaviours were observed, as well as situations where the piglets were either at risk of being crushed or were crushed. The results showed......In semi-natural environments sows often select a protected nest site at farrowing. Investigations of nest site selection under indoor conditions are scarce but suggest that sows prefer to nest and farrow under a covered area. Since feed-back from a functional nest may improve maternal behaviour...

Computer implemented land cover classification using LANDSAT MSS digital data: A cooperative research project between the National Park Service and NASA. 3: Vegetation and other land cover analysis of Shenandoah National Park

Science.gov (United States)

Cibula, W. G.

1981-01-01

Four LANDSAT frames, each corresponding to one of the four seasons were spectrally classified and processed using NASA-developed computer programs. One data set was selected or two or more data sets were marged to improve surface cover classifications. Selected areas representing each spectral class were chosen and transferred to USGS 1:62,500 topographic maps for field use. Ground truth data were gathered to verify the accuracy of the classifications. Acreages were computed for each of the land cover types. The application of elevational data to seasonal LANDSAT frames resulted in the separation of high elevation meadows (both with and without recently emergent perennial vegetation) as well as areas in oak forests which have an evergreen understory as opposed to other areas which do not.

An autocorrelation analysis approach to detecting land cover change using hyper-temporal time-series data

CSIR Research Space (South Africa)

Kleynhans, W

2011-07-01

Full Text Available Human settlement expansion is one of the most pervasive forms of land cover change in the Gauteng province of South Africa. A method for detecting new settlement developments in areas that are typically covered by natural vegetation using 500m MODIS...

Four decades of land-cover, land-use and hydroclimatology changes in the Itacaiúnas River watershed, southeastern Amazon.

Science.gov (United States)

Souza-Filho, Pedro Walfir M; de Souza, Everaldo B; Silva Júnior, Renato O; Nascimento, Wilson R; Versiani de Mendonça, Breno R; Guimarães, José Tasso F; Dall'Agnol, Roberto; Siqueira, José Oswaldo

2016-02-01

Long-term human-induced impacts have significantly changed the Amazonian landscape. The most dramatic land cover and land use (LCLU) changes began in the early 1970s with the establishment of the Trans-Amazon Highway and large government projects associated with the expansion of agricultural settlement and cattle ranching, which cleared significant tropical forest cover in the areas of new and accelerated human development. Taking the changes in the LCLU over the past four decades as a basis, this study aims to determine the consequences of land cover (forest and savanna) and land use (pasturelands, mining and urban) changes on the hydroclimatology of the Itacaiúnas River watershed area of the located in the southeastern Amazon region. We analyzed a multi-decadal Landsat dataset from 1973, 1984, 1994, 2004 and 2013 and a 40-yr time series of water discharge from the Itacaiúnas River, as well as air temperature and relative humidity data over this drainage area for the same period. We employed standard Landsat image processing techniques in conjunction with a geographic object-based image analysis and multi-resolution classification approach. With the goal of detecting possible long-term trends, non-parametric Mann-Kendall test was applied, based on a Sen slope estimator on a 40-yr annual PREC, TMED and RH time series, considering the spatial average of the entire watershed. In the 1970s, the region was entirely covered by forest (99%) and savanna (∼0.3%). Four decades later, only ∼48% of the tropical forest remains, while pasturelands occupy approximately 50% of the watershed area. Moreover, in protected areas, nearly 97% of the tropical forest remains conserved, while the forest cover of non-protected areas is quite fragmented and, consequently, unevenly distributed, covering an area of only 30%. Based on observational data analysis, there is evidence that the conversion of forest cover to extensive and homogeneous pasturelands was accompanied by systematic

Next generation of global land cover characterization, mapping, and monitoring

Science.gov (United States)

Giri, Chandra; Pengra, Bruce; Long, J.; Loveland, Thomas R.

2013-01-01

Land cover change is increasingly affecting the biophysics, biogeochemistry, and biogeography of the Earth's surface and the atmosphere, with far-reaching consequences to human well-being. However, our scientific understanding of the distribution and dynamics of land cover and land cover change (LCLCC) is limited. Previous global land cover assessments performed using coarse spatial resolution (300 m–1 km) satellite data did not provide enough thematic detail or change information for global change studies and for resource management. High resolution (∼30 m) land cover characterization and monitoring is needed that permits detection of land change at the scale of most human activity and offers the increased flexibility of environmental model parameterization needed for global change studies. However, there are a number of challenges to overcome before producing such data sets including unavailability of consistent global coverage of satellite data, sheer volume of data, unavailability of timely and accurate training and validation data, difficulties in preparing image mosaics, and high performance computing requirements. Integration of remote sensing and information technology is needed for process automation and high-performance computing needs. Recent developments in these areas have created an opportunity for operational high resolution land cover mapping, and monitoring of the world. Here, we report and discuss these advancements and opportunities in producing the next generations of global land cover characterization, mapping, and monitoring at 30-m spatial resolution primarily in the context of United States, Group on Earth Observations Global 30 m land cover initiative (UGLC).

The Association Between Urban Tree Cover and Gun Assault: A Case-Control and Case-Crossover Study.

Science.gov (United States)

Kondo, Michelle C; South, Eugenia C; Branas, Charles C; Richmond, Therese S; Wiebe, Douglas J

2017-08-01

Green space and vegetation may play a protective role against urban violence. We investigated whether being near urban tree cover during outdoor activities was related to being assaulted with a gun. We conducted geographic information systems-assisted interviews with boys and men aged 10-24 years in Philadelphia, Pennsylvania, including 135 patients who had been shot with a firearm and 274 community controls, during 2008-2011. Each subject reported a step-by-step mapped account of where and with whom they traveled over a full day from waking until being assaulted or going to bed. Geocoded path points were overlaid on mapped layers representing tree locations and place-specific characteristics. Conditional logistic regressions were used to compare case subjects versus controls (case-control) and case subjects at the time of injury versus times earlier that day (case-crossover). When comparing cases at the time of assault to controls matched at the same time of day, being under tree cover was inversely associated with gunshot assault (odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.55, 0.88), especially in low-income areas (OR = 0.69, 95% CI: 0.54, 0.87). Case-crossover models confirmed this inverse association overall (OR = 0.55, 95% CI: 0.34, 0.89) and in low-income areas (OR = 0.54, 95% CI: 0.33, 0.88). Urban greening and tree cover may hold promise as proactive strategies to decrease urban violence. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Dose-area product measurement for patients in diagnostic radiography

International Nuclear Information System (INIS)

Alkhawad, Safaa Ibrahim Awad Elkarim

2001-09-01

There is a wide spread of the utilization of medical diagnostic x-ray in Sudan upon the last years, in private clinics as well as in public hospitals. The aim of this study was to measure the doses to patients from x-ray in radiography departments in Khartoum State. Use was made of ionization chamber that measures the product of dose times the exposed area of the patient in units of Gy cm 2 . The work was performed in 7 hospitals over 250 patients. 71.2% of the patients were males and 28.8% females. From this work, it appears that the chest radiography represent 42% of the total exposure of human body organs to radiography, there was also a clear variation in doses resulting from this exposure for different x-ray machines. The results of this study were compared with similar from Germany, Finland, New Zealand and Norway; which are recently available studies. The comparison showed those investigation of abdomen, spine and pelvis result in higher radiation doses. No data for limb exposure were obtained from these countries, in Sudan exposure of the limb carry radiation doses compared to the rest of the human body.(Author)

IRSeL-An approach to enhance continuity and accuracy of remotely sensed land cover data

Science.gov (United States)

Rathjens, H.; Dörnhöfer, K.; Oppelt, N.

2014-09-01

Land cover data gives the opportunity to study interactions between land cover status and environmental issues such as hydrologic processes, soil properties, or biodiversity. Land cover data often are based on classification of remote sensing data that seldom provides the requisite accuracy, spatial availability and temporal observational frequency for environmental studies. Thus, there is a high demand for accurate and spatio-temporal complete time series of land cover. In the past considerable research was undertaken to increase land cover classification accuracy, while less effort was spent on interpolation techniques. The purpose of this article is to present a space-time interpolation and revision approach for remotely sensed land cover data. The approach leverages special properties known for agricultural areas such as crop rotations or temporally static land cover classes. The newly developed IRSeL-tool (Interpolation and improvement of Remotely Sensed Land cover) corrects classification errors and interpolates missing land cover pixels. The easy-to-use tool solely requires an initial land cover data set. The IRSeL specific interpolation and revision technique, the data input requirements and data output structure are described in detail. A case study in an area around the city of Neumünster in Northern Germany from 2006 to 2012 was performed for IRSeL validation with initial land cover data sets (Landsat TM image classifications) for the years 2006, 2007, 2009, 2010 and 2011. The results of the case study showed that IRSeL performs well; including years with no classification data overall accuracy values for IRSeL interpolated pixels range from 0.63 to 0.81. IRSeL application significantly increases the accuracy of the land cover data; overall accuracy values rise 0.08 in average resulting in overall accuracy values of at least 0.86. Considering estimated reliabilities, the IRSeL tool provides a temporally and spatially completed and revised land cover

Three Global Land Cover and Use Stage considering Environmental Condition and Economic Development

Science.gov (United States)

Lee, W. K.; Song, C.; Moon, J.; Ryu, D.

2016-12-01

The Mid-Latitude zone can be broadly defined as part of the hemisphere between around 30° - 60° latitude. This zone is a home to over more than 50% of the world population and encompasses about 36 countries throughout the principal regions which host most of the global problems related to development and poverty. Mid-Latitude region and its ecotone demands in-depth analysis, however, latitudinal approach has not been widely recognized, considering that many of natural resources and environment indicators, as well as social and economic indicators are based on administrative basis or by country and regional boundaries. This study sets the land cover change and use stage based on environmental condition and economic development. Because various land cover and use among the regions, form vegetated parts of East Asia and Mediterranean to deserted parts of Central Asia, the forest area was varied between countries. In addition, some nations such as North Korea, Afghanistan, Pakistan showed decreasing trends in forest area whereas some nations showed increasing trends in forest area. The economic capacity for environmental activities and policies for restoration were different among countries. By adopting the standard from IMF or World Bank, developing and developed counties were classified. Based on the classification, this study suggested the land cover and use stages as degradation, restoration, and sustainability. As the degradation stage, the nations which had decreasing forest area with less environmental restoration capacity based on economic size were selected. As the restoration stage, the nation which had increasing forest area or restoration capacity were selected. In the case of the sustainability, the nation which had enough restoration capacity with increasing forest area or small ratio in forest area decreasing were selected. In reviewing some of the past and current major environmental challenges that regions of Mid-Latitudes are facing, grouping by

Coastal landuse and land cover change and transformations of Kanyakumari coast, India using remote sensing and GIS

Directory of Open Access Journals (Sweden)

S. Kaliraj

2017-12-01

Full Text Available The coastal landuse and land cover features in the South West coast of Kanyakumari are dynamically regulated due to marine and terrestrial processes and often controlling by natural and anthropogenic activities. The primary objective of this study is to estimate the decadal changes and their transformations of landuse and land cover (LULC features under Level II category of USGS-LULC Classification System using Landsat ETM+ and TM images using Maximum Likelihood Classifier (MLC algorithm for the period 2000–2011. The classified LULC features are categorized as beachface land cover, cultivable lands, plantation and shrub vegetation, fallow land, barren land, settlements and built-ups, water bodies, and mining area, etc. The geo-database is prepared for LULC feature class with an attributes of name, location, area and spatial distribution, etc. It shows the larger area in beachface land cover (sandy beaches, foredunes, uplands, Teri dunes (laterite and associated nearshore landforms, plantations, cultivable lands, fallows, and barren lands are converted into built-ups and it increases more than twice in the period of 10 years. Using GIS techniques, the analysis of change detection matrix reveals that the total area of 45.90 km2 in different LULC features periodically shifted or transformed from one state to another one or more states, i.e. the beachface land cover area of 1.24 km2 is encroached for built-ups and 0.63 km2 for placer mining during the decade. Meanwhile, the area of 0.21 km2 in this cover is transformed into wetlands and saltwater bodies. During the past decade, the expansion of area in the built-ups and settlements are directly proportional to the growth of population, which produces severe threat to the coastal resources. Accuracy assessment of classified images shows the overall accuracy is estimated as 81.16% and 77.52% and overall Kappa coeffient statistical values of 0.83 and 0.76 for the year 2000 and 2011 respectively

Change In Minimum Temperature As A Response To Land Cover Change In South Florida

Science.gov (United States)

Kandel, H. P.; Melesse, A. M.

2012-12-01

Replacement of higher evapotranspirative surface materials such as water and vegetation cover by other materials such as buildings, roads, and pavements increases the Bowen's ratio from about 0.5-2.0 in rural to about ≈ 5.0 in urban areas resulting in higher surface and near surface atmospheric temperatures in the urban areas (Taha, 1997). This effect is intensified by low emissivity surfaces of the urban covers storing more heat energy during day time, but emitting less during night compared to the energy emitted by rural covers causing higher night time temperatures in urban centers, an effect called Urban Heat Island (UHI). South Florida has undergone tremendous land cover change from its pre-drainage vegetated and wetlands to post drainage agricultural and urban lands, especially after late 20th century. The objective of this study was to simultaneously analyze the land use/ land cover change and the rural/ urban minimum temperatures in south Florida for the period representing pre and post drainage states. The result shows urban sprawl increased from 8% at the beginning of the analysis period to about 14% at the end. Green vegetated areas, shrubs, and forests are found to be declined. The minimum temperature is found increased as maximum as 2°F in the urbanized stations, which remained constant or shows negligible increase in rural stations. The study dictates further micro level scrutiny in order to reach a conclusion on the development of UHI in south Florida. Key words: Bowen's ratio, emissivity, urban heat island

Sapwood area - leaf area relationships for coast redwood