Abstract. Empirical study of the isotopic features of river runoff were conducted at three hydrological posts in three different river basins: the Zakza river in the center of East European Plane (southwest of Moscow), the Dubna river (north of Moscow) and the Sosna Bystraya river in the south of central region. Samples of river water, groundwater, and precipitation for the October 2019–October 2021 were collected at weekly intervals. At total 332 samples of river water, 275 samples of groundwater and 194 samples of precipitation were collected. Precipitation was collected as an integral sample of all precipitation fallen during the week before sampling date. For each precipitation samples, the total amount of precipitation and air temperature, weighted by precipitation amount, are given according to weather station in river basin. During the observation period, there were two completely different conditions in terms of runoff formation. First, from October 2019 to October 2020, there was an unusually low spring freshet followed by a big rain flood in July. From October 2020–October 2021, there was a normal intra-annual flow pattern with high spring freshet. A significant supply of melted snow during spring freshet is the key factor influencing water regimes in these three river basins; varying degrees of anthropogenic flow regulation are also present. The new height frequency and complete data of stable isotope signature of river runoff component can help to study the response of a river runoff to climate change.

中文翻译：

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东欧平原中部三个流域河流径流、地下水和降水的稳定同位素（δ18O、δ2H）特征

摘要。在三个不同流域的三个水文站对河流径流的同位素特征进行了实证研究：东欧平面中心的 Zakza 河（莫斯科西南）、杜布纳河（莫斯科北部）和 Sosna Bystraya 河在中部地区南部。每周收集 2019 年 10 月至 2021 年 10 月的河水、地下水和降水样本。共采集了 332 个河水样本、275 个地下水样本和 194 个降水样本。降水作为采样日期前一周内所有降水的整体样本收集。对于每个降水样本，根据流域气象站给出降水总量和气温，以降水量加权。观测期间，径流形成有两种完全不同的情况。首先，从 2019 年 10 月到 2020 年 10 月，春季新鲜空气异常低，随后 7 月出现大雨洪水。2020 年 10 月至 2021 年 10 月，年内流量正常，春季新鲜度高。春季淡水期间大量融雪供应是影响这三个流域水情的关键因素；也存在不同程度的人为流量调节。河流径流组分稳定同位素特征的新高度频率和完整数据有助于研究河流径流对气候变化的响应。7 月份出现了异常低的春季新鲜空气，随后发生了一场大雨。2020 年 10 月至 2021 年 10 月，年内流量正常，春季新鲜度高。春季淡水期间大量融雪供应是影响这三个流域水情的关键因素；也存在不同程度的人为流量调节。河流径流组分稳定同位素特征的新高度频率和完整数据有助于研究河流径流对气候变化的响应。7 月份出现了异常低的春季新鲜空气，随后发生了一场大雨。2020 年 10 月至 2021 年 10 月，年内流量正常，春季新鲜度高。春季淡水期间大量融雪供应是影响这三个流域水情的关键因素；也存在不同程度的人为流量调节。河流径流组分稳定同位素特征的新高度频率和完整数据有助于研究河流径流对气候变化的响应。也存在不同程度的人为流量调节。河流径流组分稳定同位素特征的新高度频率和完整数据有助于研究河流径流对气候变化的响应。也存在不同程度的人为流量调节。河流径流组分稳定同位素特征的新高度频率和完整数据有助于研究河流径流对气候变化的响应。