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Wei L.,Capital Normal University | Wei L.,Laboratory of 3D Information Acquisition and Application | Hu Z.,Capital Normal University | Hu Z.,Laboratory of 3D Information Acquisition and Application | And 6 more authors.
Marine Pollution Bulletin | Year: 2015

Oil spills are one of the major sources of marine pollution; it is important to conduct comprehensive assessment of losses that occur as a result of these events. Traditional methods are required to assess the three parts of losses including cleanup, socioeconomic losses, and environmental costs. It is relatively slow because assessment is complex and time consuming. A relatively quick method was developed to improve the efficiency of assessment, and then applied to the Penglai 19-3 accident. This paper uses an SAR image to calculate the oil spill area through Neural Network Classification, and uses historical oil-spill data to build the relationship between loss and other factors including sea-surface wind speed, and distance to the coast. A multiple regression equation was used to assess oil spill damage as a function of the independent variables. Results of this study can be used for regulating and quickly dealing with oil spill assessment. © 2014 The Authors.

Cao S.-S.,Capital Normal University | Cao S.-S.,Laboratory of 3D Information Acquisition and Application | Wang Y.,Capital Normal University | Wang Y.,Laboratory of 3D Information Acquisition and Application | And 6 more authors.
Chinese Journal of Applied Ecology | Year: 2016

Maintaining the coordinated correlation between ecological environment and economic development is one of the important strategies in the new stage of poverty alleviation and development. Taking 714 poverty-stricken counties in contiguous destitute areas as study areas, this paper designed the ecological vulnerability evaluation indicator system based on the ecological sensitivityresilience-pressure (SRP) conceptual model, as well as the comprehensive poverty evaluation indicators from the perspective of socioeconomic development, so as to build the coupling model to reveal the coupling between ecological vulnerability and economic poverty. The results showed that Hu-Line could act as a feasible partition label to depict the spatial distribution patterns of ecological vulnerability, economic poverty, as well as their coupling degree in contiguous destitute areas, which should be fully taken into consideration the influence of Hu-Line on the east-west pattern classification of national poverty reduction. In addition, there existed a symbiotic positive correlation between ecological vulnerability and economic poverty, therefore, the strategic significance of ecological and environment protection in poverty-stricken areas should be specifically emphasized to reduce economic poverty by synchronously protecting the ecological environment. Approximately half of the counties involved in the study area were in the coordinated type of recession disorders, where the ecological environment quality and the economic development could not be synchronized. © 2016, Science Press. All right reserved.

Hu Z.W.,Capital Normal University | Hu Z.W.,Laboratory of Resources Environment and GIS | Hu Z.W.,Laboratory of 3D Information Acquisition and Application | Wei L.,Capital Normal University | And 5 more authors.
Applied Mechanics and Materials | Year: 2013

Unmanned Aerial Vehicle (UAV) remote sensing technology has the real-time ability to obtain ground images at earthquake landslide area. It makes it possible to extract landslide disaster information, support emergency rescue and decrease losses at the first second after earthquake. However, UAV remote sensing is prone to produce images with big-slant-angle. Although it is not fit for object measuring by traditional photogrammetry, it is benefit for observing slope at a better angle and extracting slope characteristics quantitatively. In this research, we define UAV big-slant-angle data as side-look images for earthquake landslide, which is based on an UAV close range photogrammetry idea. Image recognition of earthquake landslide area and three dimensional measuring of slope features will be researched. First of all, a projection datum plane along slope normal will be simulated according to the terrain surface. Appropriate images will be selected by evaluating camera pose and landslide overlapping rate. Secondly, orthogonal rotation matrixes are used to do 3D datum transformation with big-rotation-angle. Settlement of collinearity equations considering big-slant-angle condition will be researched. On this basis, dependent relative orientation among image series will be done to construct a three dimensional side-look-image model. At last, landslide image recognition, slope terrain surface reconstruction and landslide feature measurement is considered to cover the contents of earthquake landslide information extraction. Structural features and combined features can be analyzed and calculated on this basis. A rigorous solution of forward intersection in close range photogrammetry with big-slant-angle will be researched. Slope feature geometry and its relationship among images are to be considered to make a credible characteristic matching thinking big-rotation-angle exists. It has potentiality to provide variety landslide information with higher geometrical precision for cartography and risk analysis of earthquake landslide. © (2013)Trans Tech Publications,Switzerland.

Hu Z.,Capital Normal University | Hu Z.,Key Laboratory of Resources Environment | Hu Z.,Laboratory of 3D Information Acquisition and Application | Wang Z.,Tianjin Institute of Urban Construction | And 4 more authors.
Journal of Natural Disasters | Year: 2013

In this study, a road flooding information extraction model based on high resolution satellite remote sensing imagery was researched. A road flooding information extraction system was developed through the realization of inter-programming among different software environments by combining remote sensing and geographic information system technologies. First, road information extraction rules were built by analyzing spectral, geometrical and textural characteristics of fused image, which can be generated from original high resolution multi-spectral satellite remote sensing imagery. The rules were utilized to make an object-oriented road information extraction model. Second, with the knowledge of pure water s very low reflecting rate in near and mid-infrared electromagnetic wave band, and considering the complexity caused by different environmental background, an adaptive water information extraction model was built. On above bases, a component-based communication and data sharing mechanism between the application environment of remote sensing and geographic information system was established. An interactive user interface that supports model running was then developed. It can provide a spatial overlap function, extract malfunctioned road from original roads, and apply to systems with specific requirements of road flooding information extraction for correlative works.

Wang Z.,Capital Normal University | Li X.,Capital Normal University | Li X.,Urban Environmental Processes and Digital Modeling Laboratory | Li X.,Laboratory of 3D Information Acquisition and Application | And 5 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

In order to take full advantage of the multi-source remote sensing data, the concept of image fusion was proposed and nowadays, many fusion algorithms have been produced, so the adaptability of the algorithm has become a hot topic. This article aiming at the panchromatic and multispectral images of Worldview-2, uses the different fusion methods, including PCA, HPF, Gram-Schmidt and wavelet transform, to fuse the image, and evaluates the results from the aspects of the statistical information, spectral information and spatial characteristics. Then it takes the extracting vegetation as an example, analyzes the applicability of different fusion methods. The research shows that Gram-Schmidt and wavelet transform have better fusion quality and Gram-Schmidt is the most suitable method to extract vegetation for Worldview-2. © 2014 SPIE.

Guo Y.,Capital Normal University | Guo Y.,Laboratory of 3D Information Acquisition and Application | Guo Y.,Beijing Municipal Key Laboratory of Resources Environment and GIS | Gong H.,Urban Environmental Processes and Digital Modeling Laboratory | And 5 more authors.
Applied Microbiology and Biotechnology | Year: 2015

Wetland plant rhizosphere microorganisms play a significant role in the purification of ecological restoration of reclaimed water replenishment wetlands. In this study, water quality discriminant analysis indicated the wetland had a distinctive role in the purification of total nitrogen (TN), total phosphorus (TP), and nitrate (NO3 −) from reclaimed water, of which removal rates were 42.15, 47.34, and 28.56 % respectively. All the sequences of 16S ribosomal RNA (16S rRNA) gene clone library were affiliated with Proteobacteria (74.50 %), Bacteroidetes (6.54 %), Gemmatimonadetes (5.88 %), Chloroflexi (4.25 %), Chlorobi (2.94 %), Nitrospira (2.61 %), Acidobacteria (2.29 %), and Actinobacteria (0.98 %). Assessment of water quality purification and rhizosphere bacterial properties revealed that the major biogeochemical reactions were nitrogen, phosphorus, carbon, and sulfur cycles (33.70, 15.40, 14.40, and 4.90 %, respectively). In addition, approximately 5.90 and 4.60 % of the clones are closely related with the minor biogeochemical degradations of antibiotics and halogenated hydrocarbons, which were the typical characteristics of reclaimed water wetland different from freshwater wetlands. The finding of water quality discriminant is consistent with that of bacterial community, but the latter was a more powerful method than the former which reveals possible implications of wetland plant purification on the reclaimed water. © 2014, Springer-Verlag Berlin Heidelberg.

Liu K.,Capital Normal University | Liu K.,Urban Environmental Processes and Digital Modeling Laboratory | Liu K.,Laboratory of 3D Information Acquisition and Application | Liu K.,Beijing Municipal Key Laboratory of Resources Environment and GIS | And 20 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2010

Remote sensing has become a primary tool to identify and classify the wetland vegetation. Recently, more and more hyperspectral remote sensing is applied in wetland researches, in particular, for wetland vegetation classification. Moreover, the in-depth research on the ground spectral characteristics of wetland vegetation is very significant in classifying the remotely sensed images. The Wild Duck Lake, a typical freshwater wetland, was selected as the research area. The reflectance spectra were acquired for the typical wetland plant communities with an ASD FieldSpec HH spectrometer (350 - 1050 nm). Then, the reflectance spectra were re-sampled to emulate the band configuration of the airborne hyperspectral imagery (OMIS) across the visible to near infrared (NIR) wavelengths. Second-derivative analysis was applied to these transformed spectra in order to identify which spectral bands were the most biological explanative for the differentiation of wetland vegetation in the Wild Duck Lake. The research established seven distinct wavelength domains across the visible to NIR wavelengths that have importance for mapping wetland vegetation in the Wild Duck Lake. The six frequently occurring bands (presumably with enhanced differentiation power) were identified within six of seven spectral domains. Considering the unique spectral pattern of submergent plant species, three additional bands in Zone VI (810. 6 nm, 821. 1 nm, 833.0 nm) were identified having special significance. This research ultimately identified nine optimal spectral bands (515. 3nm, 553. 1 nm, 626.5 nm, 687. 5 nm, 733. 9 nm, 810. 6 nm, 821. 1 nm, 833. 0 nm, 966. 8 nm) that appeared to contain the majority of the wetland information content of the full spectral resolution, 50-band, hyperspectral signatures. The nine bands can be used to differentiate wetland vegetation types very well. Submergent vegetation had the unique absorption or reflection features at the band 810. 6 nm, 821. 1 nm, 833. 0 nm, which was obviously different from other vegetation covers. The absorption feature at 515.3 nm and reflection feature at 553. 1 nm of floating vegetation were more obvious compared with emergent plants, hygrophyte and mesophyte. Floating vegetation, hygrophyte and mesophyte demonstrated more distinct absorption feature at 687.5 nm than the emergent species, while emergent species displayed the clear absorption characteristic at 733. 9 nm. Hygrophyte showed evidence of absorption at 626. 5 nm. It was found that mesophyte lacked reflectance characteristic at 626. 5 nm. However, it exhibited the strong absorption characteristic at 966. 8 nm. The result would not only provide a scientific basis for hyperspectral remote sensing image processing and wetland vegetation mapping in the Wild Duck Lake, but also supply reference for identifying and classification of freshwater wetland vegetation applying remote sensing technology.

Guo C.F.,Capital Normal University | Guo C.F.,Urban Environmental Processes and Digital Modeling Laboratory | Guo C.F.,Laboratory of 3D Information Acquisition and Application | Guo C.F.,Beijing Municipal Key Laboratory of Resources Environment and GIS | And 4 more authors.
Advanced Materials Research | Year: 2014

Wetlands is a superior way to purify water environment. However monitoring and discriminating among vegetation covers types are critical to understanding population distribution, biogeochemical functioning and the process of wetland recovery. Recently, remote sensing technology has become an important tool to monitor wetland vegetation. Typical wetland plants Bidens Pilosa, Scirpus planiculumis, Phragmites australis and Typha angustifolia in Wild duck wetland were chosen, and Mann-Whitney U-test were used to analyze the spectral characteristics. There were typical vegetation spectral characteristics of dominant species spectral reflectance curve. There are differences among reflective spctral characteristic of species, especially in the "green peak" and "steep reflection". According to the results of Mann-Whitney U-test, the highest frequency bands appeared in702-715,732-745,747nm, the classification precision of Bidens pilosa, Scirpus planiculumis and Phragmites australis are 100%, 100%, 80%. While It is difficult to distinguish Typha angustifolia from other species effectively using the three spectrum regions. © (2014) Trans Tech Publicutions, Switzerland.

Xiong W.,Capital Normal University | Xiong W.,Urban Environmental Processes and Digital Modeling Laboratory | Xiong W.,Laboratory of 3D Information Acquisition and Application | Xiong W.,Beijing Municipal Key Laboratory of Resources Environment and GIS | And 8 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2013

Reclaimed water as supplemental source of urban rivers and lakes is regarded as an important approach to improve urban aquatic ecological environment. However, high concentration of nitrogen and phosphorus from reclaimed water can easily lead to eutrophication. Bacteria in constructed wetland are known to play an important role in aquatic ecological remediation. The community structure and diversity of cultural associated bacteria in roots of reed (phragmites australis) growing in reclaimed water management system (reclaimed water treatment unit, cycling water treatment unit, oxidation ponds) in Beijing Olympic Park was investigated in summer and autumn by 16S rDNA cloning, Amplified Ribosomal DNA Restriction Analysis (ARDRA), and sequence homology comparison. Canonical Correspondence Analysis (CCA) and Two way Indicator Species Analysis (TWINSPAN) were used to estimate and statistical test the effects of environmental variables and other explanatory variables on bio-communities, especially to unravel the simultaneous response of the species in a bacteria community to environmental variations when the effects are hidden by other large sources of variation. Cluster analysis on bacteria clones showed that 29 operational taxonomic units (OTUs) were identified based on the similarity of ARDRA banding profiles in 328 cultural clones. Environmental changes resulted into a seasonal shift of bacteria community on community density and diversity in reclaimed water management system. Community density and evenness of root-associated aerobic bacteria in summer increased 76. 37% -96. 70% than those in autumn. Kinds of inflow (reclaimed water or cycling water) and types of matrix both contributed to spatial variability of bacterial community. There was relative high community diversity and density with reclaimed water inflow and IVCW matrix in reclaimed water treatment unit. Spatial variability of bacteria community in summer increased with altering dominant species in each unit and more accidental species. Therefore, reclaimed water treatment unit in summer with the highest community density (29. 9 × 107 CFU/ g roots weight) and the Shannon-Weaver (H'=1. 824). CCA and TWINSPAN analysis revealed that OTU1 and OTU28 in constructed wetland system were with the wide ecological amplitude, which contributed to the stability of constructed wetland system and hardly disturbed by water viabilities, played an important role in material metabolism and energy metabolism. NH+ 4,TN,ORP,TP in water drived seasonal variability of community structure of reed root-associated aerobic bacteria, while NO- 3, TDS, pH, Sal in water leaded to spatial variability community structure of reed root-associated aerobic bacteria of summer reclaimed management system.

Guo C.,Capital Normal University | Guo C.,Urban Environmental Processes and Digital Modeling Laboratory | Guo C.,Laboratory of 3D Information Acquisition and Application | Guo X.,Capital Normal University | And 2 more authors.
Spectroscopy Letters | Year: 2016

Increasing amounts of recycled water have been used in wetlands; as such, monitoring the growth status of wetland plants with remote sensing technology is of great significance to restore and reconstruct wetland added by recycled water. In this paper, Phragmites australis and Typha angustifolia were selected. Spectral reflectance was determined in the visible domain to avoid the influence of leaf water on the established model; chlorophyll and nitrogen contents were measured as data sources. Statistical analysis, including correlation analysis and stepwise regression analysis, was conducted to estimate chlorophyll and nitrogen contents with different derivative transform spectra, namely, first derivative reflectance spectrum (FDS), band depth (BD), continuum-removed derivative reflectance (CRDR), band depth ratio (BDR), and normalized band depth index (NBDI). After the selected bands were statistically analyzed, we found that the range of 550-750 nm, particularly 700-750 nm (red edge range), was the key range to estimate biochemical parameters. Single removal cross-validation results showed that the optimum models of chlorophyll content inversion in reeds, cattails, and combined samples were BD, CRDR, and NBDI, respectively; the corresponding R2 were 0.87, 0.83, and 0.81. The respective RMSE values were 0.16, 0.15, and 0.33; the optimal models of nitrogen content inversion in reeds, cattails, and combined samples were BD, CRDR, and BD, respectively; the corresponding R2 were 0.69, 0.72, and 0.79. The respective RMSE values were 0.15, 0.11, and 0.17. Kruskal-Wallis non-parametric test and multi-way ANOVA were then performed; results revealed that data types and biological differences greatly influence the inversion model; by contrast, spectral derivative transform and vegetation type difference did not significantly affect the inversion model. Our results could be used as a scientific basis of the non-destructive growth status monitoring of wetland plants. It also provided a reference for restoration and management of wetlands supplied with recycled water. © 2016 Taylor and Francis Group, LLC.

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