The study, which covers the period between 2014 and 2018, was carried out in the city of Naberezhnye Chelny, Republic of Tatarstan, Russia. The aim of the study was to examine the biochemical response of maple trees growing in the anthropogenic environments. Leaf samples from 600 trees (Acer platanoides L. and Acer negundo L.) were collected at monthly intervals from June through August. Sampling was performed early in the morning (11 a.m.) in the middle of the month. The study offers statistical data on the tannin content, determined via permanganometry; the ascorbic acid concentration, found via titration with 2.6-dichlorophenolindophenol; the ascorbate oxidase activity determined by absorbance at 265 nm; and the polyphenol oxidase activity, found by the spectrophotometric method. Relatively higher ascorbate oxidase activity was detected in August among ash-leaved Acer platanoides L. and Acer negundo L. in areas with strong anthropogenic impact. Due to increased air pollution, maple trees were found to exhibit an increase of polyphenol oxidase activities. The condensed tannin content in Norway maple trees dropped over time: by 1.24 in July (avenue); by 0.94 (buffer area) and 0.76 (avenue) in August. The condensed tannin content in the ash-leaved maple trees also decreased: by 0.69 (buffer area) and 0.22 (avenue) in July; by 0.37 (buffer area) and 0.61(avenue) in August.

这项研究涵盖2014年至2018年之间，是在俄罗斯Ta斯坦共和国纳贝雷兹尼·切尔尼市进行的。该研究的目的是检验在人为环境中生长的枫树的生化响应。600棵树的叶子样品（Acer platanoides L.和Acer negundoL.）是从6月到8月的每月间隔收集的。在月中的清晨（11点）进行采样。该研究提供了通过高锰酸法测定的单宁含量的统计数据。抗坏血酸浓度，通过用2.6-二氯苯酚吲哚酚滴定而测得；通过265nm处的吸光度测定抗坏血酸氧化酶活性；用分光光度法测定了多酚氧化酶的活性。八月份，在灰烬的Acer platanoides L.和Acer negundo中检测到相对较高的抗坏血酸氧化酶活性。L.在强烈的人为影响区域。由于增加的空气污染，发现枫树显示出多酚氧化酶活性的增加。挪威枫树的单宁浓缩含量随时间下降：7月下降1.24（大道）；在八月份下降了0.94（缓冲区）和0.76（大道）。灰烬的枫树中单宁的浓缩含量也降低了：7月减少了0.69（缓冲区）和0.22（大道）。在八月份减少了0.37（缓冲区）和0.61（大道）。