A composite adsorbent was prepared by montmorillonite and biochar from peanut shell. The adsorption experiment of the Cu2+ ions from aqueous solution by the montmorillonite-biochar composite was carried out in detail. The effects of initial concentration of Cu2+ ions in aqueous solution and contact time on adsorption efficiency were studied. FTIR spectroscopy, SEM and TEM analyses, standard N2 adsorption-desorption techniques, EDS and XPS were used to evaluate the physico-chemical, textural and crystalline properties of the montmorillonite-biochar composite. Results showed that the montmorillonite-biochar composite was mesoporous material. The surface of montmorillonite-biochar composite was rough with irregular layer structure. According to the experimental data, pseudo first order kinetics model and pseudo second order kinetics model were applied. The adsorption process fits well with the pseudo second order kinetics model. The predominant process is chemisorption, which involves a sharing of electrons between the adsorbate and the surface of the adsorbent. Adsorption data were correlated well by Freundlich isotherm models and adsorption process was chemical. It is concluded that the montmorillonite-biochar composite can be used as an effective adsorbent for the removal of Cu2+ ions from aqueous solutions.

The assessment of forest site quality at early stages of stand development is very essential for scientific afforestation and forest management. In order to enhance the accuracy of the existing models, a new site quality assessment model based on Genetic Algorithm-Radial Basis Function (GA-RBF) was proposed to predict site index (stand dominant height). Data used in this study came from 980 permanent sample plots for Chinese fir (Cunninghamia lanceolata) plantations in Fujian Province, China, which were randomly divided into the training dataset (786 plots) and the testing dataset (194 plots) with a ratio of 8:2. In this paper, the GA-RBF was compared with the radial basis function (RBF) and the traditional Quantitative Theory I (QT-I) method. The results indicated that the predicted accuracy was significantly increased by using the GA-RBF model. Furthermore, we used the existing site-specific site index table of Chinese fir to test the results of the GA-RBF and the agreement was 73.2%. Therefore, we recommend the GA-RBF for assessing site quality of afforestation land.

The prevention and control of desertification cannot be separated from the active participation of local urban and rural residents. However, only a few studies on the difference in urban and rural residents’ willingness to pay for the prevention and control of desertification and its influencing factors are available. To explore the differences in urban and rural residents’ willingness to pay for desertification prevention and control, the status quo and influencing factors of willingness to pay for desertification prevention and control among urban and rural residents were analysed by linear regression analysis method and the micro-survey data of 300 urban and rural residents in the middle and lower reaches of the Tarim River in Xinjiang, China. Results show that urban and rural residents’ willingness to pay for desertification prevention and control is affected by education level, ecological environment concern, ecological environment protection needs, attention to desertification, and cognition of desertification control effect. Several preventive measures were provided with respect to enhancing residents’ awareness of desertification prevention and control, raising residents’ income and push forward systematic innovation.

A survey of environmental gamma radiation levels is attempted in the geographical site under construction to establish a petrochemical industry. The knowledge of natural background radiation is one of the significant steps in establishing the chemical industry. Some chemical operations such as chemical refinement may sometimes influence the natural radiation levels. The attempt of measurement of natural background gamma levels in the present paper is to establish the baseline data, which on further measurements will be useful to analyse the changes in natural background radiation levels at the time of operation of a chemical plant. The present investigation shows the activity levels of gamma radiation in the site under construction at 65 locations. The gamma levels are found to vary from 1459 μGyy-1 to 2765 μGyy-1 with the average of 2141±304 μGyy-1. It is to be noted from the study that the average gamma radiation levels at two sample locations, cement mixing point (2307 μGyy-1) and stone crushing point (2529 μGyy-1) have been elevated. The elevated radiation levels at the two sample locations can be attributed to the radioactive dust emitted in the process of crushing stones and cement mixing.

The construction industry is among the pillars of China’s economic development. However, it causes high carbon emission and high energy consumption, which should be considered when drafting energy saving and emission reduction policies. The sustainable development of this industry lies in the effective estimation of carbon emission efficiency and implementation of energy-saving and emission reduction measures in accordance with local practical situations. First, investigations on the emission efficiency of the construction industry and relevant emission reduction policies in foreign developed countries were reviewed in this study. Second, the carbon emission efficiency of the construction industry in 13 prefecture-level cities in Hunan Province (China) from 2011 to 2017 were estimated using the SBM (Slack Based Measure) model involving unexpected outputs. Finally, specific suggestions on reducing the carbon emission of the construction industry were proposed. CO2 emissions in the construction industry increase annually as a response to economic development and urbanization. The carbon emission efficiency of Hunan Province’s construction industry maintained a stable growth rate in 2011-2017. The industry achieved an annual growth rate of 2.7% in 2017 from that in 2011. The carbon emission efficiency of Changsha City, Zhangjiajie City, and Yiyang City were relatively higher than those of other cities in the province. Such findings serve as a reference to the quantification of potential of Hunan Province in reducing the carbon emission, the formulation of specific carbon emission reduction goal, the augmentation of the means to evaluate energy saving and emission reduction, and the development of a low-carbon construction industry.

The concentration of chlorophyll-α in the Gorontalo Bay is necessary to be observed since it could describe the condition of water richness. The semi-enclosed Gorontalo Bay morphology causes the status of water fertility to be largely determined by the input of inorganic or organic materials originating from the mainland. This study aimed to figure out the concentration and horizontal distribution pattern of the chlorophyll-α then further to decide the relationship between the concentration of chlorophyll-α and the nutrients in the Gorontalo Bay. There were fifteen sub-sampling sites selected based on coastal and ecological characteristics. Results showed that the distribution pattern of chlorophyll-α in the Gorontalo Bay in June and July 2017 was dissimilar and its concentration ranged from 0.984 to 3.744 mg.m-3. In addition, there was a positive and substantial relationship between chlorophyll-α and phosphate (p<0.01). Nonetheless, there was no significant correlation between chlorophyll-α and nitrate (p>0.01) and ammonia (p>0.01).

Over the past decades, overall ecological conditions in the Caspian Sea have deteriorated. However, a comprehensive understanding of lake-wide spatial differences in anthropogenic pressures is lacking and the biological consequences of human impacts are poorly understood. This paper therefore aims at assessing the individual and combined effects of critical anthropogenic pressures on the Caspian Sea ecoregions. First, cumulative pressure scores were calculated with a cumulative environmental assessment (CEA) analysis. Then, the individual contribution of anthropogenic pressures was quantified. Finally, ecoregion-specific differences were assessed. The analyses show that both cumulative and individual pressure scores are unevenly distributed across the Caspian Sea. The most important individual pressures are invasive species, chemical pollution and poaching. This uneven distribution of pressure scores across Caspian Sea ecoregions creates new challenges for future conservation strategies, as different ecoregions usually require different conservation measures.

The hydrophyte Azolla filiculoides can be a useful model to assess if TiO₂ NPs may in some way alleviate the Cd injuries and improve the ability of the plant to cope with this metal. With this mechanistic hypothesis, after a pre-treatment with TiO₂ NPs, A. filiculoides plants were transferred to cadmium-contaminated water with or without TiO₂ nanoparticles. After 5 days of treatment, cadmium uptake, morpho-anatomical, and physiological aspects were studied in plants. The continuous presence of TiO₂ nanoparticles, though not increasing the uptake of cadmium in comparison with a priming treatment, induced a higher translocation of this heavy metal to the aerial portion. Despite the translocation factor was always well below 1, cadmium contents in the fronds, generally greater than 100 ppm, ranked A. filiculoides as a good cadmium accumulator. Higher cadmium contents in leaves did not induce damages to the photosynthetic machinery, probably thanks to a compartmentalization strategy aimed at confining most of this pollutant to less metabolically active peripheral cells. The permanence of NPs in growth medium ensured a better efficiency of the antioxidant apparatus (proline and glutathione peroxidase and catalase activities) and induced a decrease in H₂O₂ content, but did not suppress TBARS level.

The quality of feed, including its microbiological characteristics, is important for the organization of full-value feeding of animals in agriculture. So, the means of non-reagent processing of feeds, including cavitation treatment, are becoming more widespread. In our study, it was shown that the amount of mesophilic aerobic and facultative anaerobic microorganisms (QMAFAnM) decreases after a 5-min treatment of the test samples (chalk, fuz, bran, and zeolite) (1.1–35 times) compared to untreated samples, while an increase in the duration of exposure is proportional to the expression of the bactericidal effect. A study of the bioluminescent response of the test strain Escherichia coli K12 TG1 under the influence of the test samples showed inhibition of bioluminescence under the action of chalk and an increase in luminescence during incubation with fusa and bran. When examining the growth rates of strains E. Coli 675 and Bifidobacterium longum B379M, it was found that water and zeolite treated with cavitation suppressed the growth of E. coli 675, while the growth of Bifidobacterium longum B379M was higher than the control values at the end of the experiment. So, cavitation processing can cause the death of microflora of feed additives, at the same time, as a result of the dissociation of a complex of organic polymers, contributing to the positive response of probiotic strains. These studies can be used in agriculture in the preparation of feed additives from waste from the processing industry.

In the context of improving permeable reactive barrier (PRB) filters, axial and a centripetal column tests were performed to compare their evolution in terms of chemical and hydraulic performances. For both tests, the MgO reactive media, made of crushed (< 10 mm) spent MgO–C refractory bricks was used to treat water contaminated with Co and Ni by raising the pH and promoting hydroxide precipitation. As opposed to the traditional cylindrical axial configuration, the centripetal column consists of an annulus of reactive media through which the water flows from the outer radius towards the inner radius. Under similar conditions (total reactive mass, porosity), the centripetal column is expected to delay the breakthrough of contaminants because of its higher cross-section and lower flow speeds at the entrance of the media. However, as we found in this study, the design of a granular radial filter poses several technical problems. Indeed, a breakthrough of the contaminants, accompanied by a decline in pH, was observed much sooner in the centripetal (100 pv) than in the axial (375 pv) filter. This lower performance was deemed to be due to a hydraulic shortcut and was supported by the results of a tracer test (average renewal volume much lower (199 ml) than the theoretical one (7530 ml)) as well as the observation of preferential clogging upon dismounting the radial filter. While the design of a filter that induces a purely radial flow still poses a technical challenge, this study contributes to advance the knowledge for centripetal radial filtration of groundwater in PRBs.