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Liang Q.B.,Southwest forestry University | Liu Y.G.,Southwest forestry University | Tian K.,Southwest forestry University | Tian K.,National Plateau Wetlands Research Center
Advanced Materials Research | Year: 2013

The study aimed at phosphorus and nitrogen removal by honeycomb cinder modified with Zinc chloride (ZnCl2). By bench-scale batch experiments, honeycomb cinders with different modification time and ZnCl2 dosage were modified and its adsorption capacities were evaluated by methylence blue as the adsorbate. Under the optimal modification conditions, large amount modified honeycomb cinders were prepared to remove the phosphorus and nitrogen from domestic sewage, which different operating conditions of honeycomb cinders dosage, and contact time were considered. The results show that removal efficiencies of total phosphate (TP), orthophosphate (PO4 3--P), total nitrogen (TN) and ammonia nitrogen (NH4+-N) could reach 89.9%, 96.7%, 18.9% and 23.3% under the optimal conditions, respectively. Modified honeycomb cinders might be an effective and low cost adsorbent for phosphorus removal. © (2013) Trans Tech Publications, Switzerland. Source


Liang Q.,Southwest forestry University | Liu Y.,Southwest forestry University | Tian K.,Southwest forestry University | Tian K.,National Plateau Wetlands Research Center | Wang W.,Southwest forestry University
Chinese Journal of Environmental Engineering | Year: 2013

The neural network model was build to predict treatment efficiency of the constructed wetland because of the complex decontamination mechanism and nonlinear. In 4 month experiment, 56 groups of COD removal rate were obtained from constructed wetland with different compound substrates. To predict the COD removal rate, the models based on the radial basis function(RBF) and Elman neural network were presented after wavelet de-noising under the environment of Matlab. The results showed that the RMS error of RBF and Elman neural network are 0.0186 and 0.0163, respectively, which means that the precision of the model is high. The COD removal rates are 49.4%~59.0%. Source


Yang H.-S.,Southwest forestry University | Tian K.,National Plateau Wetlands Research Center | Yao X.,Southwest forestry University | Cao P.-L.,Southwest forestry University
Chinese Journal of Ecology | Year: 2015

Dam enlargement can lead to the increasing distribution area of flooded wetlands. In the present study, soil samples along a flooding gradient in Lashihai Plateau wetland were collected and analyzed in order to understand the distribution patterns of soil organic matter and total nitrogen, and the differences in their contents before and after the dam impoundment were compared. The results showed that compared to the unflooded area, the contents of soil organic matter and total nitrogen in the flooded area were higher. Also, as the flood intensity increased, the contents of organic matter and total nitrogen first increased and then decreased. As far as the same flood intensity was concerned, the soils severely affected by human activities (e.g., abandoned cropland soils) had lower levels of organic matter and total nitrogen than the undisturbed soils (e.g., meadow soil). The analysis of variance (ANOVA) showed that the contents of organic matter and total nitrogen were significantly changed in the perennial waterlogging area (P<0.05) but not in the seasonal flooding area with the alternation of wet and dry seasons (P>0.05). Correlation analysis showed that flood intensity was positively correlated with soil organic matter and total nitrogen contents (P<0.01). Also, soil organic matter was positively correlated with total N (P<0.01). The results could provide basic data to evaluate the impacts of dam impoundment on wetland ecosystems and also a theoretical basis for protection and management of plateau wetland ecosystems. © 2015, editorial Board of Chinese Journal of Ecology. All rights reserved. Source


Lai J.-D.,Southwest forestry University | Tian K.,Southwest forestry University | Tian K.,National Plateau Wetlands Research Center | Guo X.-L.,National Plateau Wetlands Research Center | Fan Q.-F.,Southwest forestry University
Wetland Science | Year: 2014

The marshes, marshy meadows and meadows in Napahai wetlands were selected to study the distribution and variation of soil organic carbon and soil microbial biomass carbon contents. The results showed that the mean contents of organic carbon of various soil layers (0-10 cm, 10-20 cm, 20-30 cm and 30-40 cm) in marshes, marshy meadows and meadows in the depth of 0-40 cm varied from (18.02 ± 0.24) to (258.44 ± 3.37) g/kg. They were significantly different (p<0.05) and declined as the increase of soil depth. The mean contents of microbial biomass carbon of various soil layers in the marshy meadows, marshes and meadows all were higher in the surface soil layer (0-10 cm), the contents were (446.23 ± 98.72) mg/kg, (204.23 ± 44.90) mg/kg and (158.64 ± 65.24) mg/kg, respectively. It appeared the similar regularity of the vertical variations as soil organic carbon. The mean contents of soil microbial biomass carbon of the marshes, marshy meadows and meadows were different, that of marshy meadows was the highest (940.00 mg/kg), but that of meadows was lowest. There were significant correlation relationships between the soil organic carbon content, microbial biomass carbon content and soil moisture, suggested that the drainage by human disturbances was the main cause. Source


Yao X.,Southwest forestry University | Tian K.,Southwest forestry University | Tian K.,National Plateau Wetlands Research Center | Xiao D.-R.,National Plateau Wetlands Research Center | And 2 more authors.
Chinese Journal of Ecology | Year: 2015

Effects of different intensities of pig forage disturbance on plant community diversity nd soil physicochemical properties in meadow wetlands in Napahai Natural Reserve were studied. The results showed that the species number, plant diversity (including indexes of Shannon diversity , Margalef richness, and Pielou evenness), and biomass (below- and aboveground) decreased as the grazing intensity increased. As the soil depth increased, the soil bulk density decreased first and then increased under light-intensity forage but its change was reversed under medium to heavy disturbance. The content of soil organic matter decreased as the grazing intensity increased. The soil organic matter content also decreased with the increase of soil depth, especially in the upper layer. Unreasonable grazing of pig was the main reason causing decrease in plant diversity, destruction of soil structure, and decline in content of soil organic matter. © 2015, editorial Board of Chinese Journal of Ecology. All rights reserved. Source

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