Ming Da Liu

A Study on Release of Nutrients from Ash Fertilizer

To study the effect of straw ash dosage and the function of drying temperature on nutrient losses, imitate disk granulation technology was used to make ash compound fertilizer; the water immersion test was chosen to study the effect of ash on nutrient leaching characteristics of ash compound fertilizer. The results show that the total nutrient loss was the least at drying temperature of 80°C; with the rise of ash content from 15% to 20%, the release content of nitrogen and phosphorus increase, indicated that ash is able to retard the release of nitrogen and phosphorus, the dissolution rate slows down with reducing ash content, which indicates adding ash can extend the time of nutrient supply, and the effect increased with the rise of ash content.

Cytochrome P450 Content in Gut of Earthworm (Eisenia fetida) for Monitoring Pahs Contaminated Soil

Polycyclic aromatic hydrocarbons (PAH) are known to be pollutants in soil, however there are no effective methods available for determining their ecotoxic effects. We investigated Cytochrome P450 (P450) in earthworms (Eisenia fetida) as a potential biomarker of PAH pollutants in soil. Three types of PAHs were tested which included phenanthrene (Phe), fluoranthene (Fla) and pyrene (Py). Earthworm gut was selected to measure the total P450 content in cellular microsomes. Dose-response relationships between total P450 content in earthworm gut and PAH concentration (60, 120, 240, 480 and 960μg kg-1 soil (dry weight)) were determined for different exposure durations (1, 3, 7 and 14 days). Results showed that the content of P450 in earthworm changed with exposure to each of PAHs. Biphasic effects were identified in response to each of PAHs tested, in which total P450 content increased due to short, low concentration doses, and decreased due to longer, high concentration doses. Alterations to total P450 content in the presence of PAHs, show that it is a promising biomarker for identifying ecotoxic pollutants at sublethal dose ranges in soil. Further research to identify the specific activity of P450 isoenzymes could further develop and also complement this tool.

Effect of Silicon on Phosphorus Adsorption of Two Synthetic Iron Oxides

Iron oxides play an important role in controlling P activity and availability in environmental systems. Two iron oxides (goethite and ferrihydrite) were synthesized characterized by X-ray diffraction, transmission electron microscopy and N2 adsorption method. To investigate the effect of silicon on phosphorus adsorption of them, batch equilibration method was used. Attempts were made to explore the mechanisms involved by eliminating effects of pH and accompany ions. Results reveal that the ability of two kinds of iron oxides adsorbed phosphorus were as follows: ferrihydrite > goethite. Compared with the control, silicon inhibited the adsorption of phosphorus on two iron oxides, and this effect increased with the increasing of silicon content. Langmuir, Freundlich and Temkin equations could be used to describe the adsorption characteristics of phosphorus on iron oxides well, but the Langmuir model was optimal. With silicon addition, the adsorption equilibrium constants (K) decreased of the phosphorus absorbed on iron oxide, the free energy(ΔG)dropping degree increased, the maximum adsorption capacity(Xm)and maximum buffering capacity (MBC) reduced.

Effect of Different Biochars on Yield and Yield Components of Wheat on Different Soils

Effects of two types of biochars from wheat straw (SB) and hard miscellaneous woods (WB), combined with two types of soils on the growth and yield of wheat were evaluated to identify biochar addition to suitable soils on crop yield for accelerating biochar application. Plant growth variables and yields were studied in order to assess the agronomic efficiency of biochar. Our results showed that both biochar additions to an alkaline soil had little or negative effect on plant growth and wheat yield. However, to neutral soil, addition of both biochars could improve plant growth and increase significantly the wheat yield. There were significant differences on effective spikelet, number of seeds, above ground biomass and no significant differences on total spikelet, TKW among different treatments which SB was applied in neutral soil, whereas there were no significant differences on any aforementioned index at application of WB in neutral soil. Further analysis indicated that effect of SB on yield was better than that of WB, and 6% SB and 2% WB were the best for neutral soil respectively.

Evaluation and Source Analysis on Heavy Metal Pollution of Vegetable Garden Soil in the Urban-Rural Area of Fushun City

Total of 40 soil samples were collected in vegetable garden soil in the urban-rural area of Fushun city. Heavy metal elements were evaluated including Cu, Zn, Pb, Cd , Cr, Ni, As and Hg. Soil environmental quality was evaluated by a combination of the single quality index method and the complex quality index method. Meantime, the soil potential ecological hazard was evaluated by Hakanson method. It will provide scientific basis for regional agricultural production, environmental protection and industry structural adjustment. The study showed that eight samples were contaminated by Ni, exceeding rate of 20.0%, and seven samples were contaminated by Cu, exceeding rate of 17.5%. In comprehensive study, light polluted accounted for 12.5%; warning and safety level accounted for 87.5%. At the same time, the order of the potential ecological risk of single-factor was Cd>Hg>Cu>Ni>As>Pb>Zn>Cr. Integrated potential ecological hazard was slight with the number of 25.48. Statistical analysis, correlation analysis and factor analysis all suggested that concentration of Cu, Ni, Zn and Hg were mainly affected by human activities, Pb, Cd, Cr and As were mainly controlled by parent rocks.

Rural Drinking Water Disinfection Technology and Research Progress of Application

With the living standards improvement of rural residents, people pay more attention to the safety of drinking water in China. As the final step in drinking water treatment, disinfection technology has received much attention. At present, drinking water disinfection process is mainly involved in chlorine disinfection, chlorine dioxide disinfection, chloramine disinfection, disinfection of potassium permanganate, ozone disinfection and ultraviolet disinfection. However, due to limitations in rural economic conditions and management level, only ozone disinfection and ultraviolet disinfection are suitable for rural areas in China. This paper described some of the application problems and limitations in drinking water disinfection process, as well as the select principle in rural areas. The principle, research status, trends and issues in application of ozone and ultraviolet disinfection technology were emphatically introduced. Finally, the development of drinking water disinfection technologies was discussed.

Effect of Growing Medium on the Physiological Characteristics of Organic Rice Seedling

An experiment was conducted to study the effects of different growing mediums on rice seedlings. Nine kinds of growing mediums were used: AN, AR, BN, BR, CN, CR, DN, DR, mixtures of decomposed chicken feces, soybean cake, plant ash and two organic acid (N and R) with different proportions; CK, a commercial growing medium (XinZu), used as control. Chlorophyll content, soluble sugar, peroxidase activity and root vigor of rice seedlings were analyzed. Results showed that rice seedlings in BR were stronger, with higher contents of chlorophyll, soluble sugar and peroxidase activity. The root vigor of rice seedlings was enhanced in BR. It was indicated that BR could be used successfully as growing medium for organic rice seedling.

Effect of Nickel on Living Organism and the Research Progress

Nickel is a kind of rare metal which is widely distributed in the earths crust, and is mainly used in manufacturing alloy. Nickel is a trace element essential to animals and plants growth and development, but high concentration of nickel will hamper the growth of plants and animals, and even produce toxic effects. This paper summarizes the physical and chemical properties of nickel, the sources of organisms exposed to nickel and the influence of different concentrations of nickel on animal and plant, and summarizes the relevant research progress.

Characteristics of Cu2+ Adsorption by Modified Rice Straw

In this paper, modified rice straw was investigated for its Cu2+removal ability from aqueous solution. The effects of environmental factors on metal biosorption were studied under static state, including initial concentration of metal ions, sorption time, initial pH value and adsordent dosage. In addition, the relevant equilibrium, kinetics were discussed. The results showed that the rice straw which was modified by NaOH had been improved greatly in its Cu2+removal ability. The rice straw had good effects on adsorption of low concentration of Cu2+ solution. The adsorption data fit Langmuir isotherm model well, the maximum adsorption capacity for Cu2+ reached 8.48 mg·g-1. The adsorption of Cu2+ on the modified rice straw was a very rapid process, the kinetics fit a pseudo-second-order equation well. The pH value had prominent effect on the removal rate of Cu2+, adsorption efficient could reach over 92% when pH value was between 5 and 6.5. With increasing adsordent dosage, the removal rate of Cu2+ increased.

Removal of Pb (II) from Aqueous Solution by Blast-Furnace Slags

Five blast-furnace slags were used as adsorbents to remove Pb (II) from aqueous solution. Kinetic studies showed that the sorption process was best described by pseudo-second-order model. Among Langmuir, Freundlich and Temkin isotherms, the Freundlich isotherm had a better fit with the simulation of the adsorption of Pb (II).