Advanced Materials Research Vols. 356-360

Abstract: This research is to study the distributive characteristics of soil microorganisms at river wetland on Mongolian Plateau in Inner Mongolia. The results showed that the quantities distribution of various floras of soil microorganisms in different plots (such as bump-top and in-between-bumps in enclosed and grazing regions, low floodplain and high floodplain) at wetland of the Xilin River are the same, which is bacteria＞actinomycetes＞fungi.In enclosed region, the amounts of bacteria are higher than that of other regions. Since is under natural restoration process in enclosed region, there is no significant difference between bump-top and in-between-bumps. At bump-top, it is seasonally flooded, and at in-between-bumps, there is always ponded water to cause high water content. Since high water content is not in favor to the survival of actinomycetes, the number of actinomycetes at bump-top is higher than that at in-between-bumps. Though there is low requirement of water for fungi, the number of fungi at bump-top is higher than that at in-between-bumps. In grazing region, there are more soil microorganisms at bump-top due to shorter flooded time and better air ventilation. At bump-top, organic matter is much richer, due to resupplied from animal manure, withered grass and falling leaves, which is in favor to the reproduction of actinomycetes and fungi. Since there are mostly hydrophilic plants and less biodiversity at in-between-bumps, the number of soil microorganisms is smaller. In floodplain region, the amount of bacteria at low floodplain is higher than that at high floodplain, due to higher water content, which is in favor to the reproduction of bacteria. Actinomycetes are basophilic bacteria. The amount of actinomycetes at low floodplain is higher than that at high floodplain, since high water content has led low floodplain to alkali soil. The amount of fungi at high floodplain is higher due to more suitable environment for survival and reproduction.

Abstract: Oil field exploitations have a considerable impact on environmental security. The method of oil field environmental security evaluation method should be introduced into oil field exploitations for protection of environmental security. The frame model of pressure-state-response (P-S-R) was selected for oil field environmental security evaluation. Assessment levels were classified into five levels according to the value of synthetical index (SI), which was determined by the calculation of information entropies and value assignment of analytic hierarchy process. Finally, quantitative assessments of oil field environmental security situation were presented.

Abstract: Oil field exploitations effected the environmental security, so the mehtod of oil field environmental security early warning should be introduced into oil field environmental management. The grey forecasting model was selected to predict individual index of environmental security early warning for oil field. Based on the individual index prediction, the method of environmental security early warning (synthetical early warning) was presented. Finally, according to the analysis of the results of oil field environmental security early warning, the regulation direction of oil field environmental security was proposed.

Abstract: Acorus gramineus Soland., Canna chineresisw, Calla palustris., Rhododendron simsii, Aspidistra elatior and Chamaedorea elegans, were rooted in 0.3m media. The media were composed of 0.15m gravel and 0.15m mixture of sand and soil, and the volume proportion of sand and soil was 2:1. The plants were grown in six 0.5x1.0m concrete ponds that were filled with a further 0.3m of effluent from an oxidation ditch operated in a sequential batch mode, treating eutrophic wastewater from a university. The water was sampled daily for total N and total P and retained for seven days. A control pond devoid of plants was not included. The levels of total P and total N declined to a maximum of 60-77.6% of initial for total P and 86.7-98% for total N within four days. Since levels stayed constant for total N but rose for total P, four day retention would minimize amounts of these nutrients leaving the ponds. The conclusion can be gotten through analysis that the plant’s absorb isn’t the main cause of total N and total P remove for constructed wetland, but there are some effect by the plant adaptability, so in the design process of eutrophic wastewater treatment, plants could be chosen on their aesthetic merits to enhance the wetland system’s sight effect. And the hydraulic residence is better inside 4 days in the surface constructed wetland design process. The mechanisms involved in nutrient decline were not investigated.

Abstract: Although there were many studies focused on the PCDD/Fs emissions from different incinerators, but the emissions in a whole plant have seldom been reported. This paper investigated the distributions and congener profiles of the PCDD/Fs in the stack gas, fly ash, dust in the precipitator and slag from an whole medical waste incinerator. The result showed that 1) the PCDD/Fs of the dust in the precipitator had the highest level in all the samples. 2) 2,3,7,8-TCDD was the important characteristic factor in the TEQ values of most samples.

Abstract: In order to control regional acid deposition pollution, it is necessary to determine scientific regional control targets for atmospheric acid deposition. This study proposed a method to conduct multi-site simulation using the VSD model and the simulation results were plotted by cumulative frequency distribution curves. Then the regional acid deposition control targets were determined based on the analysis of the restoration of the soil in the region under different deposition scenarios in the target years. The method was applied in the Guangzhou-Dongguan-Huizhou region. To analyze the control targets for acid deposition in this region, 25 sites were simulated by VSD model based on onsite soil sampling and investigation, and the results were plotted by cumulative frequency distribution curves. The results indicated that when S deposition was controlled alone and if the protection rate was 80%, the S control targets should be 7.68-12g.m^-2.yr^-1 in the short-term and 10.24-16g.m^-2.yr^-1 in the long-term; the short-term and long-term S deposition control targets should be 5.12-8g.m^-2 .yr^-1 和7.68-12g.m^-2 .yr^-1 if the protection rate was 95%. When the S and BC depositions were controlled simultaneously and if the protection rate was 80%, the S control targets should be 2.56-4 g.m^-2 .yr^-1 in the short-term and 5.12-8 g.m^-2 .yr^-1 in the long-term when BC deposition was 6.4-12.8 g.m^-2 .yr ^-1 ; and the S control targets should be 2.56-4 g.m^-2.yr^-1 when BC deposition was 4.8-9.6 g.m^-2.yr^-1. If the protection rate was 95%, the S control targets should be 0.64-1 g.m^-2.yr^-1 in the short-term and 5.12-8 g.m^-2.yr^-1 in the long-term when BC deposition was 6.4-12.8 g.m^-2.yr^-1; and the S control targets should be 0.64-1g.m^-2.yr^-1 in the short-term and 2.56-4g.m^-2.yr^-1 in the long-term. When BC deposition was 2-4 g.m^-2.yr^-1, S deposition should be controlled to 0.64-1g.m^-2.yr^-1 for the protection rate of 80% and 95%, and some manual restoration measures are required at the same time

Abstract: Based on the review of some typical secrete industry discharges in China in recent years, the characteristics of secrete discharge are summarized as follows: most of the secret discharge industries are of heavy pollution with high toxicity, heavy COD concentration and expensive treatment cost, and these companies include private, state-owned or multinational corporations, and some even own a variety of honors. Main reasons for secret emissions include inadequate environmental policies and institutional issues, no-in-place law enforcement, low costs of illegal discharge and lack of economically viable technologies, etc. Therefore, some measures are proposed: reform of environmental policies and performance evaluation mechanism, improve the capacity of environmental supervision, increase the cost of illegal discharge, innovation development model, implementation of cleaner production, and strengthening international cooperation, etc. Introduction

Abstract: On the basis of generalizing the conception of river ecological compensation(eco- compensation) reasonably, according to river characteristics and people’s practice experience, the paper gives discussion on river eco-compensation mechanism from the angle of coupling system. By analyzing the characteristics during theoretical study and practical experience of river eco-compensation, to ameliorate the limitations, the paper describes the framework of effective river eco-compensation mechanism. For Xin'an River as an example, in the light of the present compensation theory, the author gives river eco-compensation mechanism overall framework based on co-construction and sharing ideas. Learning from the research progress and achievement of different areas, the paper gives typical examples analysis about trans-boundary river eco-compensation implementation on water quantity and quality joint operation level. Finally, the paper puts forward the improvement measures and further research emphasis of river eco-compensation.

Abstract: Abstract. Efficient full use of fly ash is still an important issue which has been troubled by the developing countries like China, and a large area subsidence as a result of coal mining also give rise to serious damage for agricultural soils. The agricultural soil profile reconstruction is great significance with fly ash as a substrate because of combining the two problems. In this paper, the feasibility of soil reconstruction is discussed through studying the physio-chemical properties and hydraulic characteristics of fly ash. The results show that the physio-chemical properties of fly ash layer in reconstruction soil profile tend to healthy development with rehabilitation time increasing. Though fly ash layer has a higher water content and poor ability of water vertical upward movement compared to surface soil, but the parameters values are basically appropriate to crop production and not evidently decreasing yields. As for potential groundwater pollution due to solute downward transport of reconstruction soil, we will start further research and draw up solution.

Abstract: The present status about wastewater treatment at highway affiliated facilities of China including characteristics of wastewater and treatment technology, the effect of wastewater treatment were investigated. It was found that wastewater quantity was mainly depending on traffic volume entering the service area. Integrated process of wastewater treatment was the main technology used at highway affiliated facilities. 80.4% of the total devices discharge the water which can meet the “Integrated Wastewater Discharge Standard (8978-1996)”. About 69.6% of water was discharged into the road ditches, 22.2% was used for greening and flushing toilet. 3.9% of water evaporated naturally, 2.7% of water was discharged into the river, and only 1.6% was used for agricultural irrigation. The results provided scientific reference for the construction, improvement and management of wastewater treatment device at highway affiliated facilities by relevant departments in the future.