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Since1999, Hunan Province has embarked on a series of ecological projects to return farmland to forests across the province to explore the impacts of anthropogenic policies and actions on changes in vegetation cover between 2000 and 2015.It is important to understand the impacts of anthropogenic and climatic changes on regional vegetation cover change is an important guide for formulating reasonable environmental protection and restoration strategies in the region .this paper analysed the influence of climate and anthropogenic activities on the change of vegetation cover of Hunan Province during 2000-2015, which combined with an improved vegetation-climate residual regression model at the meta-scale. During 2000-2015, the contribution of anthropogenic activities to the increase of vegetation cover was 49%, 53%, 62% and 66% for unconverted forest land, grassland, unused land and water area respectively, while the contribution of climatic factors was 51%, 47%, 38% and 44% respectively. At the same time, all the land use types of contributions to vegetation cover change in Hunan Province is positive, and the land type without forest land change has the largest contribution to vegetation cover change in Hunan Province at 66.28%, while the land type where other land is converted to unused land has a lower contribution to vegetation cover change.

Manganese (Mn) exclusion in the Mn hyperaccumulator pokeweed (Phytolacca americana L.) was investigated. Hydroponic experiments were carried out to observe the responses of pokeweeds continually exposed to high levels of Mn. In this study, crystals were observed to appear firstly on the root hair, and soon after, more crystals appeared on the root surface, and crystals of Mn phosphate were observed to appear on the root surface in a time sequence negatively correlated with the number of leaves treated with 5 mM Mn. Crystals were identified via phase analysis of X-ray diffraction and element analysis, and these white insoluble crystals were identified using XRD to be Mn phosphate, with the molecular formula (Mn,Fe)3(PO4)2·4H2O. The nutrient solution pH increased from 4.5 to about 5.6 before the crystals appeared. Mn phosphate crystals appeared in all solutions except those without phosphate and emerged earlier in the solutions containing no Fe. Compared with control group, pokeweed accumulated much more Mn in the leaves when treated without phosphate or Fe. The present study suggests that pokeweed can exclude Mn by means of rhizosphere precipitation by phosphate to form Mn phosphate crystals that accumulate on the root surface. Although the detailed mechanism requires further investigation, this study provides the first direct evidence of a novel strategy to inhibit Mn uptake in the roots of a hyperaccumulator in a P-enriched environment. [ABSTRACT FROM AUTHOR]

DOI: 10.3155-1047-3289.61.8.850 ABSTRACT Thirty-three soil samples were collected from the Luling, Liuer, and Zhangji coal mines in the Huaibei and Huainan areas of Anhui Province, China. The samples were analyzed [...]

Summary: Estimation with longitudinal Y having nonignorable dropout is considered when the joint distribution of Y and covariate X is nonparametric and the dropout propensity conditional on (Y,X) is parametric. We apply the generalised method of moments to estimate the parameters in the nonignorable dropout propensity based on estimating equations constructed using an instrument Z, which is part of X related to Y but unrelated to the dropout propensity conditioned on Y and other covariates. Population means and other parameters in the nonparametric distribution of Y can be estimated based on inverse propensity weighting with estimated propensity. To improve efficiency, we derive a model‐assisted regression estimator making use of information provided by the covariates and previously observed Y‐values in the longitudinal setting. The model‐assisted regression estimator is protected from model misspecification and is asymptotically normal and more efficient when the working models are correct and some other conditions are satisfied. The finite‐sample performance of the estimators is studied through simulation, and an application to the HIV‐CD4 data set is also presented as illustration. [ABSTRACT FROM AUTHOR]

Cooking oil fumes (COFs) are the major sources of indoor air pollution in Asia. It is well known that alveolar cells are key participants in the development of respiratory system; however, it still remains unknown whether alveolar cells are affected by COFs. Therefore, the present study investigated the effects of COFs on alveolar cells (A549 cells) and illuminated its apoptotic mechanism in response to COF-PM2.5 exposure. When A549 cells were exposed to COF-PM2.5, cell viability was substantially decreased, while the generation of ROS increased, and LDH levels and CCK-8 levels gradually changed within a dose-dependent manner. The nitrite concentration in the supernatants was augmented, while the SOD activity and GSH recycling were decreased upon COF-PM2.5. Moreover, COF-PM2.5 treatment increased mRNA levels of COX-2, inducible NO synthase, and TNF-α, and Elisa assay suggested that secretory proteins IL-6 and TNF-α were also increased. Furthermore, the Bax/Bcl-2 mRNA ratio was increased, and cleaved caspase-3 protein was activated in the A549 cells. Strikingly, COF-PM2.5 induced the phosphorylation of STAT1 at Tyr701/Ser727 and activation of NF-кB and ERK1/2, p38, and JNK of the MAPK pathway. In short, our study suggested that COF-PM2.5 resulted in inflammation, apoptosis, and cell damage in A549 cells, which might be modulated via the activation of MAPK/NF-кB/STAT1 pathway. [ABSTRACT FROM AUTHOR]

Vanadium in coals may have potential environmental and economic impacts. However, comprehensive knowledge of the geochemistry of V in coals is lacking. In this study, abundances, distribution and modes of occurrence of V are reviewed by compiling >2900 reported Chinese coal samples. With coal reserves in individual provinces as the weighting factors, V in Chinese coals is estimated to have an average abundance of 35.81 μg/g. Large variation of V concentration is observed in Chinese coals of different regions, coal-forming periods, and maturation ranks. According to the concentration coefficient of V in coals from individual provinces, three regions are divided across Chinese coal deposits. Vanadium in Chinese coals is probably influenced by sediment source and sedimentary environment, supplemented by late-stage hydrothermal fluids. Specifically, hydrothermal fluids have relatively more significant effect on the enrichment of V in local coal seams. Vanadium in coals is commonly associated with aluminosilicate minerals and organic matter, and the modes of V occurrence in coal depend on coal-forming environment and coal rank. The Chinese V emission inventory during coal combustion is estimated to be 4906 mt in 2014, accounting for 50.55 % of global emission. Vanadium emissions by electric power plants are the largest contributor. [ABSTRACT FROM AUTHOR]

This research concerns the adsorption of CuII and NiII using zero-valent iron nanoparticles supported by kaolinite (nZVI-Kaolinite). The characterization studies indicated that the surface of kaolinite or the kaolinite fragments were filled with nZVI particles. The kinetics of CuII and NiII adsorption were evaluated for various contact times. The adsorption of CuII and NiII at different initial concentrations was examined by injecting 0.5 g of adsorbent to achieve equilibrium. The adsorption of CuII and NiII was a chemisorption process, which fitted well with the Freundlich and the Temkin isotherm models. The low value of activation energy suggests the occurrence of a redox process and both physical and chemical processes for CuII and NiII adsorption respectively. The negative values for the Gibbs free energy (δG0) and enthalpy of adsorption (δH0) revealed that the adsorption process was spontaneous and exothermic. Both surface diffusion and pore diffusion were involved in the rate-limiting step. The possible removal mechanisms involved redox, adsorption, precipitation, and co-precipitation, depending on the adsorption process studied (CuII or NiII adsorption). [ABSTRACT FROM AUTHOR]