Tannery industry is common in many parts of the world, which is polluting groundwater ecosystems and producing major heavy metals and sodium chloride. The present study is aimed at some morphological characters in phytoremediation of heavy metals and ions from tannery effluents by using halophytic species such as Ipomoea pes-caprae and Clerodendron inerme. The morphological characters were analysed at an interval of 30, 60, 90 and 120 days. The results indicated that all the morphological characters were increased with an increasing concentration of tannery effluents and no injury symptoms in growth condition. It may be concluded that these halophytic species are potentially suitable for phytoremediation of heavy metals from the tannery effluent contaminated soils, which will reclaim the soil for further use as crop cultivation or crop improvement.

To study the variations in microorganisms and enzyme activity during sewage sludge composting, the dynamic changes in temperature, enzyme activity and microorganism composition were studied by co-composting municipal sludge and corn straw. The results show that the pile underwent mesophilic, thermophilic, and cooling phases and that the high-temperature duration (³ 50 °C) had reached 5 days, which meets harmlessness requirements. During the composting process, the protease, arylsulfatase (ARS) and cellulase content increased gradually; urease content first decreased and then increased rapidly; and peroxidase (POD) content first increased and then decreased. Ureibacillus, Bacillus, Pseudomonas, Flavobacterium and Sporosarcina were the dominant bacteria during sludge composting. Microorganisms played different roles at different stages of the composting. Ureibacillus and Bacillus were the dominant strains in the mesophilic and thermophilic phases, respectively, and Pseudomonas and Flavobacterium were the dominant strains in the cooling phase. Sporosarcina mainly played a role later in the thermophilic and cooling phases. The effect of different bacteria on enzyme activity varied; Pseudomonas played a clear role in promoting the production of urease while Bacillus had a clear inhibitory effect on the production of urease. Ureibacillus inhibited the production of ARS, POD, protease and cellulase. By studying the changes in microbial and enzymatic activities at different stages of sludge composting, it is possible to thoroughly explore the nature of the latter and provide a reference for optimizing composting processes.

Thallium (TI) is a kind of emerging contaminant with strong toxicity. In this study, a low-cost, renewable, biologically low-toxic and environmentally friendly fly ash/chitosan (FACS) composite adsorption material was synthesized by combining the characteristics of chitosan and fly ash to remove thallium from wastewater. SEM, FTIR and XRD analyses showed that the adsorbent mainly contained silicate compounds, and the surface of the particles contained a large number of micro porous structures. The adsorption process was rapid, reaching the adsorption equilibrium after 60min. When the pH value was 8, FACS had the best adsorption effect on TI, which was not conducive to the adsorption of TI in either strong acid or strong base environment. The co-existence of Fe3+ and Mn2+ could facilitate the adsorption of TI by FACS. The adsorption isotherm data were better fitted for the Freundlich model, while the Second-order kinetic model was more suitable for describing the kinetic data. Since the main chemical bond composition and chemical groups of FACS would not change after the adsorption of TI, the removal rate of TI was still high when it was reused after desorption. Because of its simple operation, low cost and reusability, FACS is considered to have certain potential in the removal of TI from wastewater.

Various measures are implemented to promote the construction of China’s ecology. These measures aim to accelerate the green transformation of the economy and promote the rapid development of energy conservation and environmental protection industry under the promotion of relevant policies. Consequently, the numbers of enterprises and the market scale have shown explosive growth. However, energy conservation and environmental protection enterprises are faced with lack of technological innovation, shortage of capital, and high cost. Effective measures must optimize the efficiency of capital allocation. To evaluate the capital allocation efficiency of energy conservation and environmental protection enterprises, 26 listed companies of energy conservation and environmental protection in the Yangtze River Delta of China were selected as samples. Monetary capital, accounts receivable, inventory, fixed assets, and construction in progress were used as input scalars. Net profit, undistributed profit, and surplus reserve were used as output variables. The Data Envelopment Analysis (DEA) model was used for analysis. Results show that capital allocation efficiency of 11 sample companies is DEA-effective. Power, heat, gas, water production, and supply industry rank first with the real estate industry divided by industry. Shanghai ranks first in the regional division. Specific improvement strategies are proposed for non-DEA effective sample enterprises.

Soil is a vital media in transmitting contaminants in the environment. Contamination of soils by trace metals has received much attention due to their associated toxicity, persistence, bioaccumulation and non-biodegradability that is harmful to the ecology. This study assayed the concentrations of trace metals in topsoils of the vicinity of Roundhill landfill using inductively coupled plasma-mass spectrometry (ICP-MS) and X-ray fluorescence (XRF), compared the detection capabilities of the two techniques and determined ecological risks of the contaminants using geographical information system. Soils were collected from nine sampling sites around Roundhill landfill in the Eastern Cape and analysed for five trace metals using the two techniques. Mean concentrations of Cr, Cu, Ni and Zn determined by ICP-MS and XRF were normally distributed (p<0.05) from the parametric test while no significant differences between the two datasets were established from the non-parametric test. Under-estimated elemental concentrations determined by XRF were attributed to its high detection limits, matric effects, inter-elemental peak interferences and low sensitivity of the equipment. Correlation values of Cr, Cu and Ni showed a high degree of linearity compared to Pb. Evaluated eco-risk indices revealed low to extremely high ecological risks, posed by assessed trace elements in soils. Cr had the highest potency. Assayed trace metals were ecologically harmful to soils and their origin was linked to landfill leachate pollution.

To reveal the regularity of arsenic adsorption of sediment, this study explores the law of arsenic adsorption by sediment when Fe3+ and Mn2+ coexist. The experimental results fit the first-order kinetic model and the second-order kinetic model. The surface physicochemical properties of sediment particles were analysed by scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherm and fractal dimension. Characterization of surface area and pore distribution were measured by the BET equation and BJH equation. The results illustrate that the adsorption of arsenic by sediment shows the phenomenon of rapid adsorption in the early stage, slow adsorption in the middle stage and finally adsorption equilibrium. In the presence of coexisting ions, the BET specific surface area was as high as 20.14m2/g, the pore volume as 0.047826cm3/g, the surface pore volume as 43.25cm3, and the surface fractal dimension Ds as the largest.

Urbanization and industrialization lead to the increased usage of fossil fuels for running various types of automobiles and industries in developing countries. The rapid growth of automobiles usage in major cities causes air pollution and its direct impact on public health. This impact is alarming the worsening of the health of urban dwellers. But this impact can be reduced by breathing the filtered air. Filtering of air can be done in multiple ways. Among all, filters prepared from natural materials have become popular. In this study, an attempt has been made to find the novel approach to reduce the pollutants’ level in the air by preparing prototype indoor air purifier which is designed, fabricated and tested with eco-friendly materials and adsorbents prepared from plant extractions. The three pollutants considered were CO2, SO2, and NO2. Activated carbon was used as an adsorbent for CO2 and NO2 removal, whereas Neem bark, Mango bark, Orange peel powder and Neem leaf powder were used for SO2 removal. The prototype was designed for Hyderabad city, Telangana State of India and tested at houses of five different locations (Balanagar, Jeedimetla, Zoo Park, MGBS and JNTU) which are major traffic intersections in the city. The level of pollution before and after the installation of the instrument was measured for three months (January, February, March) and analysed. Results indicate the improvement of air quality after filtration.

A kinetics model was established to investigate the effects of condensation of water vapour on the growth of coal-fired particles. The effects of operating parameters on particle growth were numerically studied, including growth time, supersaturation, flue gas temperature, and particle number concentration. The results showed that almost all the particles could grow rapidly more than 2.7 microns in tens of milliseconds. When initial supersaturation is constant, the higher the temperature of flue gas, the larger the amount of condensable vapour and the final diameter of particles. Moreover, when the gas temperature is constant, the higher the degree of saturation, the larger the driving force for vapour condensation and the particle size distribution becomes narrower. Additionally, with the increase of particle number concentration, the competition between particles for water vapours become more intense, and the final diameter for particles are smaller.

The Huangbaihe River is the primary water source for Yichang city. Large-scale phosphate mining activities in the Huangbaihe River Catchment area could change the proportion of streamflow components; therefore, an accurate simulation of streamflow and its components is vital to enable effective water resource management and protection. In this study, the Soil and Water Assessment Tool (SWAT) model with input data from China Meteorological Assimilation Driving Datasets (CMADS) and the traditional gaging station was applied to simulate hydrological processes in the upper reaches of the Huangbaihe River Catchment area. The constructed model was calibrated and validated using observed streamflow on a monthly scale. Parameter sensitivity and uncertainty analysis were conducted using the Sequential Uncertainty Fitting (SUFI-2) algorithm, and the strengths of calibration and uncertainty analysis were evaluated by applying the p-factor (proportion of measurements covered by the 95PPU) and r-factor (mean thickness of 95PPU band separated using the standard deviation of measurements). The results show that the SWAT model with the two kinds of data source proficiently simulated streamflow records compared with only one data from traditional gauging stations in both the calibration and validation periods at the whole outlet. For the calibration (2009-2012) and validation (2013-2016) periods, the statistical indexes are all good at the Xuanmiaoguan gaging station and the whole outlet. Furthermore, spatiotemporal changes in overland runoff and lateral flow were strongly consistent with precipitation, and significant differences in the contribution from hydrological elements to the water balance were observed between high and low-flow years.

The nitrogen concentration/flux of water is very sensitive to the response of Net Anthropogenic Nitrogen Inputs (NANI), but the research on the dynamic response of nitrogen concentration to NANI is still rarely reported. In this study, the source of Zhaoshandu water source in Zhejiang Province, China, was used as the research object. The dynamic response of total nitrogen (TN) concentration to NANI in the basin was quantitatively analysed from 2005 to 2014. The results show that the NANI of the water source has a growing trend. It has increased by 6.73% in ten years. The average annual average of NANI is 85.76 kg (hm2·a-1), which is 1.7 times the national average of 2009. The average contribution rate of atmospheric nitrogen, chemical fertilizer nitrogen, food and feed nitrogen and crop fixed nitrogen is 40.98%, 34.06%, 20.25% and 4.7% respectively. The spatial difference of NANI is large, showing an increasing trend from the upstream mountainous area along the downstream. The sub-basin 2 is the key source of nitrogen pollution in this water source. NANI is the only independent variable of the TN concentration regression model with a variance interpretation rate of 55.4%. In the future, it is necessary to reduce the nitrogen input intensity of nitrogen, food and feed for chemical fertilizers as the main target, and to achieve the goal of water quality improvement by reducing the NANI intensity in the basin.