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Assessing the distribution and risks associated with the soil lead content in the Tieguanyin tea plantations of Anxi County is critical, given the county's significance as the primary Tieguanyin tea production area in Fujian Province. This study examined the distribution characteristics of soil lead in Anxi County's tea plantations according to the Kriging spatial interpolation of the parameters of the semivariance function of the exponential model. Moreover, the sources of lead content were analyzed, considering geological backgrounds and anthropogenic influences. Ecological risks and the issuance of early warnings were also assessed. The soil lead content in the rocks of the Tieguanyin tea plantations in Anxi County followed the order: andesite > dacite > rhyolite > granite. The soil lead content gradually decreased from the center toward the east and west, forming four distinct north–south parallel zones. High-lead-content areas were identified at the border of Jiandou, Bailai, and Hushang; in the central part of Lutian; and in the southern part of Huqiu. The high levels of soil lead in the tea plantations possibly originated from industrial and mining activities, automobile exhaust, and agricultural activities. The distribution of single-factor pollution indices and potential risk evaluation based on the Soil Environmental Quality Standard, Environmental Technical Conditions for Tea Production Area, and Environmental Technical Conditions for Organic Tea Production Area indicated that the soil in Tieguanyin tea plantations in Anxi County was clean and safe for tea cultivation. [ABSTRACT FROM AUTHOR]

The paper used the unmanned aerial vehicle (UAV) which can quickly obtain a wide range of vegetation images to capture the low-altitude aerial photograph)' and associated with the multivariate HoG features to recognize vegetation types. Firstly, the texture infonnation of the image were extracted by Gabor filter and using HSV and Lab color space transform to extract the color infonnation. Next, the image were divided into N cells, then computing the gradient of histogram of each cell based on the texture and color infonnation to fonn the multivariate HoG features. Finally, taking the cell as the classification unit, combining the random forest machine learning algorithm, vegetation types recognition model were established. Taking the Anxi County in Fujian Province as the test area, the results showed that it was feasible to identify the vegetation types by using the optical image of low-altitude aerial photography; the highest recognition accuracy in recognizing vegetation and non-vegetation was 96.04%; the recognition accuracy rate was 82.44% in recognizing vegetation types at 20 m and decreased with the height increase. Moreover, the vegetation images of aerial photography were further collected, which was captured at the Changting County of Fujian Province, as another data to prove the robustness of the model of vegetation type recognition in different areas, the highest recognition accuracy was 73.31%, the accuracy was similar compared with the result of Anxi County. In this paper, the vegetation images by using the unmanned aerial vehicle with optical camera were conveniently, econmically obtained; the proposed vegetation type recognition model can be easily applied to the field vegetation type monitoring and management as the high precision and its robustness in various regions. In addition, according to the recognition result at various aerial height, the proposed aerial height should not be too high, 20 m as the reference height of aerial photography was suitable. [ABSTRACT FROM AUTHOR]

Acrolein, a known mutagen, undergoes reaction in vitro under physiological conditions with both 2′-deoxyguanosine and native DNA to give rise to exocyclic adducts of the 5,6,7,8-tetrahydropyrimido[1,2-a]purine-10(3H)-one class having an hydroxy group at either the 6 or the 8 position. Previously we have shown that the 8-hydroxy derivative in a bacterial system has very low mutagenicity probably because in double-stranded DNA this residue exists in the open-chain aldehydic form [N2-(3-oxopropyl)-2′-deoxyguanosine] (3). To continue our investigation in this area, we needed ample supplies of the 6-hydroxy isomers. This current paper describes high-yield simple methods for the synthesis in bulk of the 6-hydroxy adduct 1 and its incorporation into DNA oligomers. The basic methods for the synthesis of the adduct 1, involve 1-substitution of dG derivatives with a 3-butenyl group, dihydroxylation of the olefin with osmium tetroxide and N-methylmorpholine N-oxide, then diol cleavage with periodate ion after incorporation of the 1-(3,4-diacetoxybutyl)-2′-deoxyguanosine into oligomeric DNA. [Copyright &y& Elsevier]

Benggangs are a special type of soil erosion in the hilly granite regions of the tropical and subtropical areas of Southern China. They cause severe soil and water loss, which can severely deteriorate soil quality and threat to the local ecological environment. Soils (red soil, sandy soil and detritus soil) were collected from collapsing wall of a typical Benggang in Changting County of Fujian Province, and their physicochemical and mineralogical properties were analyzed. Five different monovalent cations were used to saturate the soil samples to examine the specific ion effects on the shear strength and clay surface properties. Red soil had a higher clay content, plastic limit, liquid limit and shear strength than sandy soil and detritus soil. The studied soils mainly consisted of kaolinite, hydroxy-interlayer vermiculite, illite and gibbsite clay minerals. The soils saturated with K + , NH 4 + and Cs + had greater cohesion than the Li + - and Na + -saturated soils, e.g. , the cohesion of the red soil saturated with Li + , K + , NH 4 + and Cs + cations were 1.05, 1.23, 1.45 and 1.20 times larger than that of the Na + -saturated soil, respectively. While the internal friction angle was slightly different, which indicated that different monovalent cations affected the shear strength differently. K + -, NH 4 + - and Cs + -saturated clay particles had higher zeta potentials and thinner shear plane thicknesses than Li + - and Na + -saturated clay particles and showed strong specific ion effects on the clay surface properties. The changes in clay surface properties strongly affected the soil mechanical properties. Soils saturated with K + , NH 4 + and Cs + could increase the shear strength, and then increase the stability of the collapsing wall, thus might decrease the erosion intensity of Benggang. The results provide a scientific basis for the interpretation of and practical treatment of Benggang., Competing Interests: The authors declare there are no competing interests., (©2024 Huang et al.)