Effects of warming on leaf non-structural carbohydrates and carbon and nitrogen isotopes of Cunninghamia lanceolata saplings during different seasons北大核心CSCD

To reveal the response of non-structural carbohydrates (NSC) and carbon and nitrogen isotopes in plant leaves to global warming, we conducted soil warming experiments in the Fujian Sanming Forest Ecosystem and Global Change National Observation and Research Station of China. We designed two treatments: control (CT) and warming (W; cable heating, +4 ℃). Heating cables were installed 20 cm from each other at a depth of 10 cm and were heated in March 2016. In this study, Cunninghamia lanceolata saplings were used to analyze seasonal changes in leaf non-structural carbohydrates, and carbon and nitrogen isotopes. The results showed that (1) warming significantly reduced the soluble sugar, starch, and NSC content of leaves in spring but without any significant difference during other seasons. (2) Leaf δ13C increased significantly in spring and winter after warming, whereas leaf δ15N did not change significantly. (3) No significant correlation was observed between leaf δ13C, δ15N, or NSC content during the warming treatment, but a negative correlation was observed between leaf δ15N, δ13C, and sugar to starch ratio. A positive correlation between leaf δ15N and starch content was identified. In summary, when temperature increases, plants adjust the NSC content during different seasons for osmotic regulation, change the characteristics of the nutrient cycle, and alter the plant water and nutrient use strategies to maintain plant growth. In the future, we should further study the seasonal variation characteristics of NSC content and isotopes and the relationship between NSC content and the carbon and nitrogen cycles in plants under the context of long-term warming. © 2022 Science Press. All rights reserved.     

Exposure characteristics of phthalate metabolites among the Zunyi cohort of pregnant women in Southwest China

Environmental Science and Pollution Research - Reported evidence has increasingly indicated that exposure to phthalates can cause adverse pregnancy outcomes. However, phthalate exposure levels...     

水解反硝化促进污水脱氮试验研究

将水解反应器作为前置反硝化的一部分,利用水解反应器内良好的无氧环境、反硝化细菌的功能快速恢复和有机物有效供给,在不加外加碳源的情况下实现高效脱氮。实验结果表明,在外加硝氮分别为10、20和30 mg/L的情况下,硝氮去除率分别为87.9%、94.9%和92.6%。通过总氮成分研究,有机氮成分能被水解为氨氮,同时水解出水的用氧吸收速率平均高于原水的0.44 mg/(g·h),提高了约15%,有利于后续生化处理硝化反应。并且水解反应器能提高出水可生化性,与进水SCOD/COD平均值44.99%相比,出水SCOD/COD平均值为71.72%,提高了26.73%。     

Effect of BPA on the germination,root development,seedling growth and leaf differentiation under different light conditions in Arabidopsis thaliana

Bisphenol A (BPA) is a well-known environmental toxic substance, which exerts unfavorable effects through endocrine disruptor (ER)-dependent and ER-independent mechanisms to threaten ecological systems seriously. BPA may also interact with other environmental factors, such as light and heavy metals, to have a synergetic effect in plants. However, there is little data concerning the toxic effect of BPA on the primary producers-plants and its possible interaction with light-dependent response. Here, the effects of BPA on germination, fresh weight, tap root length, and leaf differentiation were studied in Arabidopsis thaliana under different parts of light spectrum (dark, red, yellow, green, blue, and white light). Our results showed that low-dose BPA (1.0, 5.0 μM) caused an increase in the fresh weight, the tap root length and the lateral root formation of A. thaliana seedlings, while high-dose BPA (10.0, 25.0 μM) show an inhibition effect in a dose-dependent manner. Unlike karrikins, the effects of BPA on germination fresh weight and tap roots length under various light conditions are similar, which imply that BPA has no notable role in priming light response in germination and early seedling growth in A. thaliana. Meanwhile, BPA exposure influences the differentiation of A. thaliana leaf blade significantly in a light-dependent manner with little to no effect in dark and clear effect under red illumination.     

Dynamics of Steppe Vegetation under the Effect of Grazing by Different Farm Animals

The process of steppe pasture digression resulting from grazing by different farm animals was studied by the transect method. Sheep, cattle, and horse pastures under similar grazing loads markedly differed in the dynamics of steppe vegetation. The most critical changes in plant communities occurred in sheep pastures, whereas the state of plant communities in horse pastures was good.     

远看乞力马扎罗的雪--肯尼亚纪行之一

八十年代，在大学里看过一部好莱坞影片“乞力马孔罗的雪”当时，我对这部电影的晦涩主题感到困惑，但对原作者海明威能在1936年就娴熟地运用现实与幻想的意识流写作手法感到惊叹，同时乞力马孔罗山（Mr. Kilimanjaro）脚下的非洲莽原景色深深地印在我的脑海。     

Fabrication of Polypyrrole/Chitosan Nanocomposite Aerogel Monolith for Removal of Cr(VI)

Three-dimensional polypyrrole/chitosan nanocomposite monoliths are fabricated by polymerization of pyrrole in chitosan aqueous solution. The static polymerization of pyrrole monomer and the cross-linking of chitosan by glutaraldehyde occur simultaneously, resulting in the self-assembly of polypyrrole/chitosan nanocomposite aerogel monolith. The addition of methyl orange and glutaraldehyde and the static reaction play key roles in the formation of the self-standing aerogel monolith. The as-prepared monolith with larger specific surface area exhibits much better adsorption capability for Cr(VI) removal in comparison with that prepared without the addition of glutaraldehyde. The adsorption process and adsorption isotherms are found to well follow the pseudo-second-order and Langmuir models, respectively. Furthermore, this polypyrrole/chitosan nanocomposite monolith is stable and recyclable. About 73.5% of the initial adsorption capability is kept after eight adsorption–desorption cycles. The polypyrrole/chitosan nanocomposite monolith can be a promising candidate for the efficient removal of Cr(VI).     

浅议清洁生产对企业环境管理的作用

本文重点论述了清洁生产对企业环境管理的作用,指出清洁生产是深化企业环境管理方式的助推剂。     

中国社会发展水平的衡量标准与实践

中国社会统计指标体系由15大类,1000多个指标构成,适应于多层次、多角度、多目的的社会发展需要,在社会发展综合评价和实践活动中发挥了重要作用。     

昆明城市生活垃圾处理产业发展的SWOT分析研究

随着城市化进程的深入,生活垃圾问题日益突出,城市生活垃圾处理产业的发展是解决“垃圾围城”困境的有效途径.昆明城市生活垃圾处理产业处于发展阶段,运用态势分析法(SWOT),系统地对昆明城市生活垃圾处理产业发展的优势、劣势、所存在的机会和威胁进行分析,并提出相应发展对策,包括完善生活垃圾处理.产业的经济激励机制;采用多种项目融资模式进行生活垃圾产业建设融资;加快静脉产业园区建设发展;打造再生资源回收利用的龙头企业;积极控制生活垃圾源头;建立垃圾排放权交易等.