Papers by Author: Hao Wang

Abstract: Bi ̊Char soil amendment has been accepted as a low-risk soil carbon sequestration method. Some other agricultural benefits also reported in previous researches. Two kinds of bi ̊Chars, produced from walnut shell and soft wood, with significantly different surface characteristics and a severe saline sandy loam soil was used in our research. Physical and chemical parameters of bi ̊Char and soil were analyzed. The results pressure plate analysis indicated that high surface area bi ̊Char can increase water retention and plant available water in severe saline agriculture soil, however, such effect wasn’t observed in all the low surface area bi ̊Char treatments. Based on these results, a simulated soil water loss experiment was conducted under 3 different temperatures (from 25 ^̊C to 40 ^̊C), with 4 bi ̊Char doses for 120 h. Our results shown that high dose of high surface area bi ̊Char can reduce the rate of soil water loss under high temperature. Such effect indicated that high surface area bi ̊Cahr can help soil hold more water under lab condition and simulated field condition. In bi ̊Char soil application, the interaction between bi ̊Char, soil and climate condition needs to be considered carefully to acheive optimum solution for both environmental and agricultural purposes.

Abstract: Based on adequate consideration of status of water resources utilization and socio-economic development in the Shanxi Provinces, the AHP method was used to calculate the weights of each index and the fuzzy comprehensive evaluation of water resource carrying capacity in the Shanxi Province was carried out from 2006 to 2011. The evaluation results indicated that the overall level of the water resources carrying capacity in Shanxi Province was contained in critical state, however, a steady rise.

Abstract: Adding biochar to agricultural soil has been suggested as an approach to enhance soil carbon sequestration. Biochar has also been used as a soil amendment to reduce nutrient leaching, reduce soil acidity and improve water holding capacity. Walnut shells and woody material are waste products of orchards that are cheap, carbon-rich and good feedstock for production of biochar. The effectiveness of biochar as an amendment varies considerably as a function of its feedstock, temperature during pyrolysis, the biochar dose to soil, and mechanical composition. Biochar was produced from pyrolysis of walnut shell at 900 °C and soft wood at 600 to 700 °C. We measured the effect of these different parameters in two types of agricultural soil in Jilin and Beijing, China, a silt clay loam and a sandy loam, on the soils’ particle size distribution and water retention characteristics. Biochars with two different doses were applied to each soil type. Soil field capacity and permanent wilting point were measured using a pressure plate extractor for each combination of biochar and soil type. The results show that the effect of biochar amendment on soil water retention characteristics depend primarily on soil particle size distribution and surface characteristics of biochar. High surface area biochar can help raise the water holding capacity of sandy soil.

Abstract: Rainfall-runoff process plays an important role in hydrological cycle, and the study on the rainfall-runoff will provide foundation and basis for research on basin hydrology and flood forecasting. In this paper, the surface runoff and subsurface flow of wheat were observed in the laboratory by artificial rainfall, and analyzed the cumulated surface runoff and recession process of subsurface flow by regression analysis. In addition, the factors affected the runoff and response of soil moisture on the runoff coefficients was also discussed. Results showed that the rainfall intensity, soil coverage and slope had important influence on the surface runoff generation, and the surface runoff was observed when the total rainfall amount exceeded 32mm and 13mm for 5°and 15° slope respectively. The cumulative surface runoff could be expressed as a power function, which had higher determination coefficient R² (0.92~0.999). The subsurface flow was only observed at the ripening period and wheat stubble treatment, and mainly affected by slope angle and initial soil moisture, whereas rainfall intensity showed little impact. The recession curve of subsurface flow can be described as a simple exponential expression or power function, which the determination coefficient was 0.88 and 0.94 by regression analysis, respectively. Moreover, there was an obvious threshold (approximately 30%) between the average initial soil moisture and runoff coefficients, which the runoff increased significantly as above the threshold.

Abstract: It is widely believed that the economic success in China is achieved at the expense of natural resources and has resulted in severe pollution of the environment, especially water resources. This study applies a hybrid input-output (IO) model linking economic and ecological systems in order to analyze water consumption and wastewater discharge in the Haihe River Basin. Within the environmental IO framework, a series of assessment indicators is calculated to assist in tracking both direct and indirect effects of freshwater consumption and wastewater discharge in the economic sector, as well as to distinguish the economic sectors that have greatest influence on water demand and pollution. Assessment results indicate that water consumption and pollution can be reduced by readjusting the structure of production, consumption and trade in the Haihe River Basin. It is concluded that in order to achieve sustainable development in the Haihe River Basin with its very poor water endowment, not only the direct but also the indirect effects on water demand and pollution should be considered when production, consumption and trade policies are formulated.

Abstract: In Tangshan area, the secondary effluent of wastewater treatment plants was used for this study. Horizontal zeolite wetland was carried out treating it. Hydraulic loading rate was the parameters for analyzing the nitrogen and phosphorus removal efficiency of pollutants from the secondary effluent of wastewater treatment plant. Zeolite constructed wetlands showed different behaviors for nitrogen and phosphorus removals.Under the optimum hydraulic loading rate, the primary pollutions were removed to a large extent.

Abstract: Environmental degradation and unsustainable use of water resources has become an obstacle to further economic development and the well-being of the population in the Li River basin. This paper explores the concept and principles of integrated water resources management (IWRM) in relation to their applicability to the Li River basin. The assessment on its physical and socioeconomic characteristics and its current institutional systems in the Li River Basin provides an appreciation of the whole river basin. Sectoral fragmentation and the absence of coordination mechanism (or body) are identified as the institutional factors in this study that caused water related issues. In order to overcome shortfalls of the current fragmented management system, formation of Watershed Management Committee is highly recommended as the core of reforming efforts, which is expected to coordinate effective planning and implementation of equitable, efficient and sustainable use of natural resources in the basin with a view to improving the sustainability of its economic development. Several other reform recommendations are also provided and expected to be a departure point towards better water governance in the Li River basin through the implementation of IWRM. Lastly we explore to what extent the proposed recommendations would be supported by the current national policy framework.

Abstract: Carbon nanotubes (CNTs)/hydroxyapatite (HA) nanocomposites have been successfully fabricated by a novel method for the biomedical applications, which is in situ growing CNTs in HA matrix in a chemical vapor deposition (CVD) system. The results show that it is feasible to in situ grow CNTs in HA matrix by CVD for the fabrication of CNTs/HA nanocomposites. Multi-walled CNTs with 50-80 nm in diameter have been grown in situ from HA matrix with the pretreatment of sintering at 1473K in air. The nanocomposites are composed with carbon crystals in CNTs form, HA crystallites and calcium phosphate crystallites, one of most important CaP bioceramics. And the CNTs content is about 1% proportion by weight among the composites in our experiments, which can enhance the HA mechanical properties and the CNTs content does not affect the HA performances. These CNTs/HA nanocomposites have the potential application in the biomedical fields.