Subjects: Geosciences >> Geography submitted time 2024-03-01 Cooperative journals: 《干旱区研究》
Abstract： The influence of different slope-facing environmental factors on the natural regeneration of Piceaschrenkiana in the middle section of the northern slope of Tianshan Mountains was investigated. A series of plotswere established on shady, semishady, semisunny, and sunny slopes at the same altitude, in a Picea schrenkianaforest to develop the structure equation model for the regeneration index which uses different slope- facingenvironmental factors. According to the environmental characteristics of the different slope- facings, therelationship between the survival status of Picea schrenkiana seedlings and environmental factors was analyzed.The results showed that the semishady and semisunny slopes were more suitable for the survival and growth ofseedlings, and the regeneration indexes of the two slopes (0.065 and 0.057) were significantly higher than thoseof the shady and sunny slopes. Litter was found to have a dual effect on the regeneration of Picea schrenkiana.The undecomposed litter layer was too thick to be beneficial to regeneration, while the rich organic matter couldpromote the formation of a high nitrogen environment in the soil, which was conducive to the regeneration ofseedlings. The influence of different slope-facing environmental factors on the regeneration index was in theorder of total nitrogen content (0.60) > adult tree density (0.46) > litter half- decomposed layer (0.37) > totalpotassium content (0.24) > organic matter content (0.23) > total phosphorus content ( − 0.16) > availablephosphorus content ( − 0.32) > litter undecomposed layer thickness ( − 0.34). Overall, the regeneration of Piceaschrenkiana seedlings in the region was best on the semishady and semisunny slopes with a closure degree ofapproximately 0.6 and litter thickness of approximately 2.5 cm, as well as high total nitrogen and total potassiumcontents in the soil.
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：【目的】探析国家科学技术学术著作出版基金发展趋势，明确资助选题方向，为出版单位申报基金及选题策划提供参考。【方法】文章根据2013—2022年学术著作出版基金资助项目名单，对资助项目的范围、数量、承接单位、语言品种（英文）等进行分类统计，同时利用Excel软件、词频软件对资助项目进行分析，并结合文献对上述内容进行分类阐述。【结果】2013—2022年学术著作出版基金共资助项目1848个，整体趋势呈现上升态势；2013—2022年承接学术著作出版基金资助的出版单位品种数呈现上涨趋势，于2021年达到顶峰；2013—2022年国家学术著作基金由83家出版社完成，其中中国科技出版传媒承接项目最多，占总数的54%，其他82家承担项目占比46%。从2018—2022年来看，资助英文项目呈下降趋势，尤其在2021—2022年出现断崖式下滑；技术、理论、研究、中国、方法等词分别为资助选题的高频词汇。【结论】基金资助方向逐步精准，面向科技前沿，且英文作品获资助下降，出版社申报选题方向应以基础理论和应用技术类选题优先。
Subjects: Biology >> Ecology submitted time 2018-05-18 Cooperative journals: 《生态学报》
Abstract：采矿及矿产品运输过程会对环境造成重金属污染进而对生物体产生危害。为定量描述艾维尔沟矿区道路两侧重金属污染程度、明确雪岭云杉叶片对重金属的吸收富集效应，通过采集雪岭云杉叶片和土壤样品，测试其铅（Pb）、锌（Zn）、镉（Cd）、砷（As）、铜（Cu）、铬（Cr）的含量，分析重金属的富集效应和空间分异特征。结果表明：（1）雪岭云杉叶片和土壤中各重金属含量差异显著（P P < 0.05），平均达86.28 μg/g，土壤中Zn、Cu超过了国家土壤质量标准的一级限制值，而As比三级限制值大41%；（2）以背景区（板房沟林场）的土壤和雪岭云杉叶片重金属为评价标准，研究区雪岭云杉叶片重金属综合污染指数为2.05，属中度污染，其中As和Pb单项污染指数较高，达3.65和2.57。研究区土壤重金属综合污染指数为1.69，属轻度污染；（3）随距离增加，除土壤和叶片中Pb含量表现为负线性递减外，As和Cu均表现为先升高后降低，土壤中Cr、Zn逐渐升高，但叶片中Cr逐渐降低，Zn变化不大；（4）冗余分析（RDA）结果显示土壤中Cu、As、Pb与雪岭云杉死树胸径和树高呈正相关关系，而Cr、Zn与其呈负相关。采矿及运输已对土壤和雪岭云杉的生长造成影响，本文对天山雪岭云杉森林的生态修复与保育具有一定的借鉴作用。
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