Carbon ecological security assessment based on the decoupling relationship between carbon balance pressure and ecological quality in Xuzhou City, China.

Building a carbon ecological security (CES) framework helps to scientifically evaluate and manage the regional carbon cycle and eco-environment and support regional ecological security patterns. This paper adopted the pressure-state-response-immune (PSRI) model and the carbon balance index method to evaluate the ecological quality and carbon balance pressure. Then, based on the decoupling model and the improved four-quadrant model, the CES framework was constructed to evaluate the changing trend of the CES of Xuzhou City from 2005 to 2020. The results showed that the carbon balance pressure of Xuzhou City showed a pattern of "low-high-low" from east to west, and most areas tended to have a carbon balance and surplus in 2020. The ecological quality showed an overall upward trend during the study period. Protection and restoration drove the response and immune index growth from 2010 to 2020. In the Thirteenth Five-Year Plan stage, the nine districts of Xuzhou City were in a stable decoupling state, and the overall decoupling process was ideal. The CES of districts showed individual differences in the general upward trend. The carbon balance pressure of Gulou and Quanshan Districts was the main factor restricting the districts' CES. Therefore, based on the empirical results, this research proposes relevant suggestions to enhance carbon ecological security to achieve regional green and low-carbon development.

Extraction and decontamination of microplastics from high organic matter soils: A simple, cost-saving and high efficient method.

This article introduces a simple, cost-saving and high efficient for the extraction and separation of microplastics (MPs) from soil with a high organic matter (SOM) content. In this study, MP with particle sizes of 154-600 µm of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC) and polyethylene terephthalate (PET) were artificially added into the five Mollisols with the high SOM. Three flotation solutions were used to extract these MPs from soils, and four digestion solutions were used to digest the SOM. As well, their destruction effects on MPs were also examined. The results showed that the flotation recovery rates of PE, PP, PS, PVC and PET were 96.1%-99.0% by ZnCl2 solution, while were 102.0%-107.2% by rapeseed oil, were 100.0%-104.7% by soybean oil. The digestion rate of SOM was 89.3% by H2SO4:H2O2 (1:40, v:v) at 70 °C for 48 h, and this was higher than by H2O2 (30%), NaOH and Fenton's reagent. However, the digestion rate of PE, PP, PS, PVC and PET were 0.0%-0.54% by H2SO4:H2O2 (1:40, v:v), and this was lower than by H2O2 (30%), NaOH and Fenton's reagent. As well, the factors influencing on MP extraction was also discussed. Generally, the best flotation solution was ZnCl2 (ρ > 1.6 g cm-3) and the best digestion method was H2SO4:H2O2 (1:40, v:v) at 70 °C for 48 h. The optimal extraction and digestion method were verified by the known concentrations of MPs (recovery rate of MPs was 95.7-101.7%), and this method was also used to extract MPs from long-term mulching vegetable fields in Mollisols of Northeast China.

Functional Assessment and Coordination Characteristics of Production, Living, Ecological Function-A Case Study of Henan Province, China.

Multifunctional state assessment was the basis of time sequence design of territory spatial development and overall utilisation. This study aimed to identify the ecological-production-living (PLE) territory spatial function to provide a basis for territory spatial planning. It took Henan Province as the research area. This study developed a methodology to assess differentiation characteristics for PLE function, a method that integrates functional merging and geographic information technology. We used the coordination degree model and spatial autocorrelation analysis to reveal the coordination of spatial functions of the province. The results were as follows: (1) During the study period, the land production function of main grain-producing areas decreased slowly, and production and living function values of the Central Plains urban agglomeration with Zhengzhou as the centre were in an upward trend. The characteristics of urban-rural dualization were prominent, and ecological function value decreased year by year. (2) The laws of territorial spatial functions had different manifestations in different stages (1990-2005 and 2005-2018). By different characteristic laws, the change in production function in the later period was bigger than that in the previous period. The living function maintained a good continuity expansion characteristic before and after. The spatial regularity distribution characteristics of ecological function were weak, and the overall environment became worse than before. (3) The territory space of middle and low coordination function types was the most important type, and the aggregation was relatively weak. Xuchang County and Weihui City showed better states of functional coordination aggregation. Lushi County, Xinxian County, and Shangcheng County, which were in the western and southern mountainous and hilly areas, showed low-low aggregation characteristics. Thus, the government will strengthen targeted control over territorial space. This study provides a reference for the overall deployment of the development and utilisation of territory space in Henan Province.

Spatial assessment of farmland soil pollution and its potential human health risks in China.

Soil pollution severely threatens agro-ecosystem stability. It is important to accurately understand the status of farmland pollution in order to protect national food safety and human health. However, information of the combined pollution level of Chinese farmland soil and associated human health risk at the national scale is relatively lacking. In this study, 5597 samples from 1781 farmland soil sites were obtained from 553 reports and combined into pollution databases of heavy metals, organochlorines, and polycyclic aromatic hydrocarbons. Based on the data obtained, this paper demonstrated the current pollution status of farmland soil, and assessed the subsequent human health risk. Results showed that the combined pollution ratio of Chinese farmland soil was 22.10%, with 1.23% of severe pollution level. Moreover, the total non-carcinogenic hazard quotients of farmland soil pollution were within the safety threshold for adults, but there was a slight non-carcinogenic risk for children. For adults, the ratio of total farmland area to total carcinogenic risk quotients above the safety threshold of 1 × 10-5 was only 1.02%, but for children, the ratio was as high as 20.75%. On the other side, food crop and vegetable plantations were the priority control farmland soil compared to other types. Meanwhile, Yunnan, Hunan, Anhui, Henan, and Liaoning were selected as the priority control provinces due to their severe pollutions and high human health risks. This study has provided a comprehensive pollution and health risk assessment. Furthermore, the spatial distribution might provide as the scientific support for accelerating the mapping of soil pollution in China, as well as developing the policy for the contaminated farmland soil management.

[Spatial Variability and Distribution Pattern of Soil Organic Matter in a Mollisol Watershed of China].

Spatial variability of soil organic matter and its distribution pattern are the hot issues of soil scientific research. Selecting Haigouhe watershed as the study area, this paper mainly focused on the spatial variability, distribution pattern and its impact factors of SOM in the surface soil by classical statistics, Geo-statistics and "3S" technology. The results showed that: compared with the other black soil areas, the SOM content in Haigouhe watershed was a little lower, there was a spatial autocorrelation, and a moderate variability. Random factors, such as human activities, cultivation measures and so on, had little impact on the spatial variation, while the structural factors had a dominant function, and there was a remarkable spatial anisotropy of SOM. The SOM content reduced gradually from east to west with the familiar changes of height, so the co-kriging interpolation, selecting elevation as the co-variate, was employed to improve the accuracy. The spatial variability of SOM and its distribution pattern in Haigouhe watershed were greatly affected by topography and land use but weakly influenced by traffic, villages and other social factors. The surrounding environment of the samples would increase the uncertainty of spatial variability and interpolation of SOM and it cannot be ignored in future studies. In summary, it was a significant scientific research to analyze the spatial variability, distribution pattern of SOM and its main impact factors in a mollisol hilly watershed of China.

Synthesis and characterization of a novel o-tolyltelluronic trimethyltin ester and its cytotoxic assessment in vitro.

A new arenetelluronic triorganotin ester, namely (Me3Sn)4[o-Me-PhTe(µ-O)(OH)O2)]2 (1) has been prepared by the reaction of o-tolyltelluronic acid and Me3SnCl in the presence of potassium hydroxide. The complex was fully characterized by elemental analysis, FT-IR, NMR ((1)H, (13)C, (119)Sn) spectroscopy and X-ray crystallography. Structure analysis revealed that the complex crystallized as Sn4Te2 units and a 1D linear chain was formed by intermolecular C-HO interactions. Cytotoxic assessments showed that the complex can induce apoptotic cell death via accumulation of ROS, collapse of the MMP and activating caspase-3. The results indicated that ROS is crucial to the cytotoxicity induced by the complex.