Li S.,Beijing Municipal Research Institute of Environmental Protection |
Li S.,Center for Industrial Wastewater Pollution Control |
Huang X.,Chinese Research Academy of Environmental Sciences |
Gong H.,Beijing Normal University |
And 5 more authors.
Journal of Natural Disasters | Year: 2015
By the impact of the natural environmental factors (such as topography, stratum lithology, geological structure, etc.) and the inducing factors (such as rainfall, earthquakes, etc.), the characteristics of the landslides distribution in space are extremely complex, however, its spatial distribution still has internal rules. This paper takes the time of "Wenchuan earthquake" extreme event as the time phasing point, quadrat-based point pattern analysis of landslide point space distribution indicates that the landslide point group showes a spatial agglomeration model before and after the earthquake. This results demonstrate that the occurrence of landslide in the study area are not random events before and after the earthquake, but the results of the natural environmental factors, or factors combination; and the landslide point spatial distribution of Wenchuan earthquake heavy disaster area has self-similar structure in statistical sence, no characteristic scale.
Li X.,Chinese Academy of Sciences |
Li X.,University of Chinese Academy of Sciences |
Li G.,Chinese Academy of Sciences |
Zhang Y.,Center for Industrial Wastewater Pollution Control |
Zhang Y.,Beijing Municipal Research Institute of Environmental Protection
Water (Switzerland) | Year: 2014
The North China Plain (NCP) is facing a water crisis under the dual impact of natural and anthropogenic factors. Groundwater levels have declined continuously since 1960, causing a series of environmental problems that have restricted sustainable development in the region. In the present study, we first utilized a previously developed 3D groundwater model to determine changes in groundwater level in the region over the past 50 years (1961-2010). We then applied grey relational analysis (GRA) to identify and ordinate major factors that have contributed to these changes. The results show an overall decreasing trend in groundwater levels in this region over the past 50 years and an increase in the water table depth at a rate of approximately 0.36 m/a. Groundwater exploitation showed the most significant correlation with the groundwater table decline, when compared with other factors including precipitation and river leakage. Therefore, human activities should be considered the primary force driving the groundwater level down. The results of this study have implications for developing criteria that consider changes in both climate and socio-economics. Furthermore, since the NCP is one of the most water-scarce and densely populated regions in the world, the analytical approach used in and the insights gained from this study are of international interest. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
Jiang L.,Peking University |
Jiang L.,Beijing Municipal Research Institute of Environmental Protection |
Jiang L.,Center for Industrial Wastewater Pollution Control |
Jiang L.,National Engineering Research Center |
And 2 more authors.
World Journal of Engineering | Year: 2014
Land use changes significantly impacts ecosystem services and functions. The estimation of ecosystem services value is conducive to clarifying the ecological changes in response to LULC changes due to urbanization. Chengde was the upper water source of Beijing and Tianjin, the ecosystem is very fragile. After a series of ecology conservation projects like "returning cropland to forestry", the ecosystem service value increased from 5100.17 x 10 7 Yuan in 1990 to 5104.08 x 107 Yuan in 2008 respectively, with the average increase of 2.3 x 106 Yuan per year. It is indicated that ecosystem service value has the potential to inform policy decisions by emphasizing the benefits of sustainable ecosystem management. So plans on land use management should be made to maintain a balance between urbanization and ecosystem health.
Zhang Y.,CAS Institute of Geology and Geophysics |
Zhang Y.,University of Chinese Academy of Sciences |
Zhang Y.,Center for Industrial Wastewater Pollution Control |
Zhang Y.,Beijing Municipal Research Institute of Environmental Protection |
Li G.-M.,CAS Institute of Geology and Geophysics
Environmental Earth Sciences | Year: 2014
The developments of cones of depression in the North China Plain (NCP) were studied to determine the possible impact of the proposed South-to-North Water Diversion Project (SNWDP) on groundwater levels. In the past five decades, the exploitation of groundwater in the NCP has been excessive. Numerous hydrological and hydrogeological problems were caused by the gradual decline of the water table in the NCP. In order to protect groundwater resources and alleviate hydrogeological problems, the SNWDP was proposed to progressively solve the shortage of water resources in northern China. In this paper, the development of cones of depression was studied to determine the possible impact of the hydrological engineering, the SNWDP. In the study, a numerical model for regional groundwater flow was created using MODFLOW. The results showed that the SNWDP is beneficial for groundwater recovery in the NCP. The area of cones of depression will be reduced to varying degrees. Some immense groundwater cones will gradually shrink. However, it will take a long time to recover groundwater environment in the NCP. © 2013 Springer-Verlag Berlin Heidelberg.
Li A.F.,Beijing Municipal Research Institute of Environmental Protection |
Li A.F.,Center for Industrial Wastewater Pollution Control |
Ning Y.Y.,Beijing Municipal Research Institute of Environmental Protection |
Ning Y.Y.,Center for Industrial Wastewater Pollution Control |
And 4 more authors.
Advanced Materials Research | Year: 2014
High concentrations of ammoniacal nitrogen in fecal sewage pose a great threat to subsequent treatment steps. The conventional removal technique in China mainly involves air stripping. However, the concentration of ammonia in the effluent is often very high, and the fillers in towers could exhibit scaling resulting in reduced lifetime in operation. Because of its high mass transfer characteristics, fluidized bed technology was used in our study of the air stripping method for improving the removal efficiency, using spherical biological ceramsites as the filler. The effects of temperature, pH, and fluidized bed residence time on the removal process were investigated. To compare the various effects of fluidized bed operation on nitrogen removal efficiency, traditional air stripping experiments were carried out using the identical gas flowrate, liquid flowrate, temperature and pH. The results show that the removal efficiency of ammoniacal nitrogen was improved using a fluidized bed. The mechanism of free ammonia mass transfer using fluidized bed technology was proposed. Finally, the filler adhesion problem was reduced and the technology was successfully applied to the air stripping of high concentration ammoniacal nitrogen from fecal sewage. © (2014) Trans Tech Publications, Switzerland.
Li A.,Beijing Municipal Research Institute of Environmental Protection |
Li A.,Center for Industrial Wastewater Pollution Control |
Dong N.,Beijing Municipal Research Institute of Environmental Protection |
Dong N.,Center for Industrial Wastewater Pollution Control |
And 4 more authors.
Environmental Technology (United Kingdom) | Year: 2015
The lab-scale and full-scale performance of a combined mesophilic up-flow anaerobic sludge blanket (UASB) and aerobic contact oxidation (ACO) process for treating acrylic wastewater was studied. During lab-scale experiment, the overwhelmed volumetric load for UASB was above 6kg chemical oxygen demand (COD) ·(m-3·d-1) since COD removal efficiency dropped dramatically from 73% at 6kg COD·(m-3·d-1) to 61% at 7kg COD·(m-3·d-1) and 53% at 8kg COD·(m-3·d-1). Further results showed that an up-flow fluid velocity of 0.5mh-1 for UASB obtained a highest COD removal efficiency of 75%, and the optimum COD volumetric load for the corresponding ACO was 1.00kg COD·(m-3·d-1). Based on the configuration of the lab-scale experiment, a full-scale application with an acrylic wastewater treatment capacity of 8m3h-1 was constructed and operated at a volumetric load of 5.5kg COD·(m-3·d-1), an up-flow fluid velocity of 0.5mh-1 for UASB and a volumetric load of 0.9kg COD·(m-3·d-1) for ACO; and the final effluent COD was around 740mgL-1. The results suggest that a combined UASB-ACO process is promising for treating acrylic wastewater. © 2014 Taylor and Francis.