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Zhang X.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at Xaut | Zhang X.,Shaanxi Provincial Academy of Environmental Science | Yu G.Q.,Key Laboratory for Geo hazards in Loess Area of Ministry of Land and Resources | Li Z.B.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at Xaut | And 2 more authors.
Water Resources Management | Year: 2014

The relationships between precipitation, vegetation and erosion are important yet unresolved issues in the field of earth surface processes. Vegetation plays an important role in controlling soil erosion. Through field simulated rainfall experiments, we analyzed the characteristics, regulation of, and correlation among the slope rainfall-infiltration-runoff, erosion and sediment under different vegetation types. The results showed that the forest effectively improved soil structure, had stronger runoff and sediment regulation and was influenced less by rainfall intensity than those under other vegetative conditions. In addition, the efficiency and pattern of the regulation of runoff and sediment varied with vegetation types as did the mechanism of action. The soil and water conservation function of forest was water storage and sediment reduction by plant root systems to reduce erosion power, increase infiltration, decrease runoff and reduce flow speed. The function of grassland was direct sediment interception based on surface vegetation canopy for runoff and sediment regulation. The root contribution to runoff and sediment reduction was relatively greater than the shoot contribution under forest conditions, whereas, the effect of shoots and roots on soil loss was almost equivalent under grassland conditions. The different spatial structures of vegetation affected runoff and sediment regulation in different ways, and plant root systems were crucial for soil and water conservation. The cumulative sediment yield of the slopes increased as a statistically significant power function of cumulative runoff. The coefficient and curve shape of function were dependent on vegetation type, soil properties, rainfall intensity and surface roughness. The process of slope runoff and sediment was divided into development, active and stable stages. These stages correlated with each other to constitute a complete rainfall-runoff and erosion-sediment process, which exhibited their own features at each stage. This study furthers understanding of the relationships between vegetation, soil erosion and precipitation. © 2014 Springer Science+Business Media Dordrecht.


Zhang Y.,Shaanxi Provincial Academy of Environmental Science | Qiu J.,Shaanxi Yanchang Petroleum Group Co. | Niu S.,Shaanxi Provincial Academy of Environmental Science | Zhou Y.,DEBL Environmental Science and Technology Development Co.
Advanced Materials Research | Year: 2012

Economic development of guanzhong area has produced a series of impact on Weihe River's water quality, that deteriorated seriously. Environmental pollution indicators conclude ammonia nitrogen, permanganate index, COD. Weihe River water quality was improved significantly through the adjustment of industrial structure, increased investment in environmental protection and policy made to protect the Waihe River. Environmental materials is very beneficial to environment.In recent years, the new environmental material technology what can be promoted in Guanzhong region, which is carrying out the zero-emission technology in heavily-polluted paper industry, it can solve the pollution problems from the source, and it play a significant role in improving the water quality of Weihe River. © (2012) Trans Tech Publications, Switzerland.


Cheng S.,Chang'an University | Li Y.,Shaanxi Provincial Academy of Environmental Science
Applied Mechanics and Materials | Year: 2013

Too much worry on the safety of nuclear power has made many people take a negative attitude to the development of nuclear power. Nuclear safety experts pointed out that the nuclear fear of people is often due to little knowledge on the nuclear power. The paper analyses comprehensively the advantages of nuclear power, the safety of nuclear power, the reasons of nuclear power accident and its implications. Basised on these, development prospects of nuclear power is discussed. © (2013) Trans Tech Publications, Switzerland.


Liang J.-N.,Shaanxi Provincial Academy of Environmental Science | Li W.-H.,Shaanxi Provincial Academy of Environmental Science | Ge Y.,Shaanxi Province Environmental Monitoring Center | Chen J.,Shaanxi Provincial Academy of Environmental Science | And 2 more authors.
Huanjing Kexue/Environmental Science | Year: 2014

Using a cascade impactor(Andersen Series NVA-800), the size-segregated atmospheric particulates were collected daily and characters of lead contents and size distribution in the particles were analyzed from melting preparation, blast furnace smelting and lead-cast processes within a lead-zinc smelter in Shaanxi province. The results showed that emissions of particulate matter were different in different processes, in which the emissions of blast furnace smelting process was 402.83 mg·h-1, while melting preparation were 182.71 mg·h-1 and 100.03 mg·h-1 in lead-cast processes. Lead contents in different sizes of particles varied in different processes. The mass fraction of lead were 111.54mg·kg-1, 68.54mg·kg-1 and 10.5 mg·kg-1 in melting preparation, blast furnace smelting and lead-cast respectively. For lead's size distribution, the melting preparation and blast furnace smelting were mainly concentrated in the coarse particles, and the lead proportion in coarse and fine particles was approximately in lead-cast processes. The proportions of lead in coarse particles were 43.42% and 47.48% in melting preparation and blast furnace smelting process respectively, while the proportion of lead in coarse and fine particles was 37.14% and was 45.72% in lead-cast processes. There had peaks in both coarse and fine particles of melting preparation and lead-cast process, but the lead peak appeared only in the coarse particles of blast furnace smelting. It also indicated that the lead's cumulative frequencies of all processes were conforming to lognormal distribution.


Zhao Y.,Southwest University | Gao M.,Shaanxi Provincial Academy of Environmental Science | Chen X.,Southwest University | Mo B.,Southwest University
Energy Education Science and Technology Part A: Energy Science and Research | Year: 2013

The Erosion-productivity impact calculator (EPIC) model was used to estimate soil erodibility (K) in a small watershed where the main soil type is purple soil. Purple soil is a typical sandy loam soil in the Three Gorges reservoir area and most distributes in southwest China. The objectives of this paper were to explain the relationship between erodibility (K) and land-uses. Spatial variability characteristics of soil erodibility (K) under different land-uses (woodland - Pinus massoniana Lamb and Robinia pseudoacacia L, economic fruit forest - Citrus reticulata Banco, cropland - Zea mays L and Lpomoea batatas, wastegrassland) were studied. Results indicated that: (1) Soil texture and human activities were the main factors that influenced the soil erodibility (K), erodibility (K) increased with the content of sand while decreased with the content of silt, clay and organic matter. (2) The order of soil erodibility (K) from large to small under six land-uses in the watershed was: waste-grassland > economic fruit forest (Citrus reticulata Banco)> woodland (Pinus massoniana Lamb)> woodland (Robinia pseudoacacia L) > cropland (Lpomoea batatas) > cropland (Zea mays L). (3) Soil erodibility (K) of the whole purple soil watershed area showed a positive trend with elevation of the watershed from east to west. Erodibility (K) of woodland (Robinia pseudoacacia L) exhibited Kupstream < Kmidstream < Kdownstream, however, the erodibility (K) under other land-use showed the opposite trend, manifesting in Kupstream > Kmidstream > Kdownstream. © Sila Science.


Liang J.-N.,Shaanxi Provincial Academy of Environmental Science | Chen J.,Shaanxi Provincial Academy of Environmental Science | Lu L.-D.,Shaanxi Provincial Academy of Environmental Science | Wang P.,Shaanxi Provincial Academy of Environmental Science
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2014

Nitrogen oxide emissions from the processing of methanol, dimethyl ether, synthetic ammonia and urea production were monitored in a certain coal chemical factory in Shaanxi province, and the nitrogen oxide emission coefficients were calculated based on the results of both monitoring and combustion experiments. It was shown that Nitrogen oxide emissions ranged from the different coal chemical production industries. The NOx discharge amounts of methanol, dimethyl ether, synthetic ammonia and urea industries were separately between 153.19 and 252.43 g/h (AV: 211.24 g/h), 22.38 and 52.20 g/h (AV: 35.39 g/h), 246.48 and 356.65 g/h (305.94 g/h), 13.70 and 26.75 g/h (19.89 g/h). Per capita production NOx emission coefficients in different industries also varied, which were 41.33~88.10 g/t (methanol), 62.27~145.25 g/t (synthetic ammonia), 213.47~322.43 g/t (synthetic ammonia), 0.21~0.41 g/t (urea). Per capita coal consumption as raw material NOx emission coefficients were respectively 30.18~52.86 g/t (methanol), 22.83~53.26 g/t (synthetic ammonia), 119.72~172.73 g/t (synthetic ammonia), 0.14~0.28 g/t (urea). Compared with two group data, NOx emission coefficients with coal as raw material were much less than those from coal combustion process.


Pan C.,Chinese Research Academy of Environmental Sciences | Zhao Y.,Shaanxi Provincial Academy of Environmental Science | Liu G.,Chinese Research Academy of Environmental Sciences | Dou G.,Chinese Research Academy of Environmental Sciences | And 2 more authors.
Journal of Cleaner Production | Year: 2014

A new, cleaner process to produce diosgenin (CAS number 512-04-9) from Dioscorea zingiberensis with much less pollutant generation has been developed based on physical separation. A demonstration factory with an annual production capacity of 200 t of diosgenin has been built in Shanyang County, Shaanxi Province, China. The new process employs several new techniques including separation and refinement of starch, reuse of acid and mechanical washing of acid hydrolyzate. Through the application of a series of cleaner techniques, the water consumption was reduced by 66.2%, the wastewater generation was reduced by 63.3%, the acid consumption was reduced by 81.1%, the residual acid in the wastewater was reduced by 93.4% and the chemical oxygen demand production was reduced by 43.7%. The overall economic benefit increased RMB 38,087 Yuan (USD 6046) per t of diosgenin. Based on the new process, the wastewater can be treated to meet the national discharge standard using a common wastewater treatment technology. © 2014 Elsevier Ltd. All rights reserved.


Hou Y.-P.,Xi'an University of Architecture and Technology | Peng D.-C.,Xi'an University of Architecture and Technology | Xue X.-D.,Shaanxi Provincial Academy of Environmental Science | Wang H.-Y.,Xi'an University of Architecture and Technology | Pei L.-Y.,Xi'an University of Architecture and Technology
Journal of Bioscience and Bioengineering | Year: 2014

Hydrogenotrophic methanogens had been considered as key species for the anaerobic digestion (AD) of industrial wastewater and municipal sludge. However, how to evaluate the activity of the hydrogenotrophic methanogens was less studied. In this study, a volumetric device and a test procedure were developed for measuring the specific hydrogen utilization rate (HUR) of anaerobic sludge. Results showed that HUR values were highly influenced by sludge concentrations because of limitation on H2 mass transfer. The critical value of sludge concentration in the test bottle should not be higher than 1 gVSS/L. Under such condition, the kinetics of HUR would not be limited by H2 mass transfer and the maximal value of HUR could be obtained. Field survey confirmed that HUR exhibits a good relationship with specific methanogenic activity (SMA) and reactor performance. An anaerobic system with a relatively high HUR was found to be beneficial for maintaining H2 partial pressure in an appropriately low level. Moreover, such system was thermodynamically favourable for the syntrophic degradation of volatile fatty acids. As a crucial parameter of the anaerobic process, HUR could be used as a key indicator for evaluating and monitoring AD processes. © 2013 The Society for Biotechnology, Japan.


PubMed | Shaanxi Provincial Academy of Environmental Science and Xi'an University of Architecture and Technology
Type: Journal Article | Journal: Journal of bioscience and bioengineering | Year: 2014

Hydrogenotrophic methanogens had been considered as key species for the anaerobic digestion (AD) of industrial wastewater and municipal sludge. However, how to evaluate the activity of the hydrogenotrophic methanogens was less studied. In this study, a volumetric device and a test procedure were developed for measuring the specific hydrogen utilization rate (HUR) of anaerobic sludge. Results showed that HUR values were highly influenced by sludge concentrations because of limitation on H2 mass transfer. The critical value of sludge concentration in the test bottle should not be higher than 1 gVSS/L. Under such condition, the kinetics of HUR would not be limited by H2 mass transfer and the maximal value of HUR could be obtained. Field survey confirmed that HUR exhibits a good relationship with specific methanogenic activity (SMA) and reactor performance. An anaerobic system with a relatively high HUR was found to be beneficial for maintaining H2 partial pressure in an appropriately low level. Moreover, such system was thermodynamically favourable for the syntrophic degradation of volatile fatty acids. As a crucial parameter of the anaerobic process, HUR could be used as a key indicator for evaluating and monitoring AD processes.


PubMed | Shaanxi Provincial Academy of Environmental Science and CAS Nanjing Institute of Geography and Limnology
Type: | Journal: The Science of the total environment | Year: 2016

Terrestrial chromophoric dissolved organic matter (CDOM) could subsidize lake food webs. Trophic state and altitude have a pronounced influence on the CDOM concentration and composition of a lake. The impact of future changes in solar radiation on high-altitude lakes is particularly alarming because these aquatic ecosystems experience the most pronounced radiation variation worldwide. Photodegradation experiments were conducted on terrestrial CDOM samples from oligotrophic alpine Lake Tiancai and low-altitude eutrophic Lake Xiaohu to investigate the response of bacterial growth to photodegraded CDOM. During the photo-irradiation process, the fluorescent CDOM intensity evidently decreased in an inflowing stream of Lake Tiancai, with the predominance of humic-like fluorescence. By contrast, minimal changes were observed in the riverine CDOM of Lake Xiaohu, with the predominance of protein-like fluorescence. The kinetic constants of photodegradation indicated that the degradation rate of terrestrial (soil) humic acid in Lake Tiancai was significantly higher than that in Lake Xiaohu (p<0.001). Soil humic and fulvic acids irradiated in the simulated experiment were applied to incubated bacteria. The specific growth rate of bacteria incubated with soil humic substances was significantly higher in Lake Tiancai than in Lake Xiaohu (p<0.05). Furthermore, the utilizing rate of dissolved oxygen (DO) confirmed that the DO consumption by bacteria incubated with terrestrial CDOM in Lake Tiancai was significantly greater than that in Lake Xiaohu (p<0.05). In summary, the exposure of terrestrial CDOM to light significantly enhances its availability to heterotrophic bacteria in Lake Tiancai, an oligotrophic alpine lake, which is of importance in understanding bacterial growth in response to photodegraded terrestrial CDOM for different types of lakes.

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