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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

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. Source

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

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. Source

Ran Q.,Capital Normal University | Pan Y.,Urban Environmental Processes and Digital Modeling Laboratory | Wang Y.,Capital Normal University | Chen L.,Capital Normal University | Xu H.,Urban Environmental Processes and Digital Modeling Laboratory
Advances in Science and Technology of Water Resources

By means of the gravity recovery and climate experiment ( GRACE) satellite and the global land data assimilation system (GLDAS), the change of groundwater storage in the Haihe River Basin over 72 consecutive months from 2004 to 2009 was investigated. On such a basis, a binary regression model for groundwater exploitation, the annual change of groundwater storage, and annual rainfall of the GRACE satellite was established based on the previously published data of rainfall and groundwater exploitation in the Haihe River Basin from 2004 to 2009. The change of groundwater storage derived from the GRACE and GLDAS data has a good correlation with the observed data, and the R2 is 0.804. Based on the annual data of change of groundwater storage and the annual rainfall data of the GRACE satellite, the estimated results of the groundwater exploitation are satisfactory, and the R2 of the binary regression model is 0.787, indicating that using the GRACE satellite data to estimate the groundwater exploitation is feasible and is a good complementary evaluation method for the traditional terrestrial investigation. Source

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

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. Source

Li D.-Q.,Capital Normal University | Li D.-Q.,Urban Environmental Processes and Digital Modeling Laboratory | Liang J.,Huazhong University of Science and Technology | Zhang L.-Y.,Capital Normal University | And 5 more authors.
Zhongguo Huanjing Kexue/China Environmental Science

Multivariate statistical methods were used to analyze the temporal variations of water quality from 1991 to 2011 in the Miyun Reservoir. The dataset consisted of 17 variables monitored monthly at three sites. Clustering analysis showed that the water quality could be divided into three groups at interannual scale: IA I(1991~1993, 1995), IA II(1994, 1996~2000, 2002~2006), IA III(2001, 2007~2011), and two groups at seasonal scale: non-flood season (November-December, January-April), flood season (May-October). Discriminant analysis (DA) was used to identify the primary parameters that resulted in the variation of water quality. Principal component analysis/factor analysis (PCA/FA) was used to extract the main sources/factors responsible for the pollution in IA I, IA II, IA III. The results demonstrated that TN and TP exceeded national II separately 0.96 times and 0.2 times. The high coefficient of variation for TP was attributed to the instability of wetland plants and human activities, and the great annual and seasonal variability resulted in the high coefficient of variation for NO3--N, the effective control of endogenous pollution such as conservation of water and soil, decreasing domestic wastewater and fertilize use and the countermand of cage culture improved water quality during 21 years, indicating the decreasing concentration of NO3--N; The seasonal variation of NO3--N took place in specific season. At interannual scale, water temperature increased with increasing air temperature; Dissolution of carbonate rock was accelerated due to increasing SO42- concentration affected by fertilizer use and industrial activities, which increased the concentrations of EC, Ca2+, Mg2+, SO42-, T-Hard, T-Alk; The concentrations of BOD5 decreased due to the internal pollution. At seasonal scale, the concentration of Mg2+ was higher in non-flood season than in flood season because of the dissolution of carbonate rock. At interannual scale, the pollution sources for IA I, IA II, IA III changed from a combined point and non-point pollution to primarily non-point pollution. The water quality was affected by the dissolution of carbonate rock in non-flood season and was impacted by the rainfall runoff in flood season. In the Miyun Reservoir, nitrogen pollution was predominantly derived from NO3--N. Enhancing the water circulation, decreasing non-point pollution (water and soil loss, fertilizer use and cage culture), and timely sediment dredging, can effectively decrease the concentrations of nitrogen, phosphorus, and organic and ionic pollutants. ©, 2015, Chinese Society for Environmental Sciences. All right reserved. Source

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