Carabid beetles of old beech forests - repeated sampling 1999-2001 and 2020-2022

This dataset compiles data investigating carabid beetles sampled from 1999 until 2001 and again from 2020 until 2022 at the same locations with identical methods. Sampling was conducted using pitfall traps. The traps consisted of a 400 ml honey jar featuring an extended PVC rim plate. They were placed in a piece of PVC pipe and covered with a metal roof. Each trap contained 200 ml of trapping fluid (50% solution of monoethylene glycol and water). From 2020 until 2022, the researchers located the exact trap locations (with a tolerance of <2 m) using the GPS locations and tree survey maps. In all years, sampling was conducted from mid-April to early November. The pitfall traps were emptied fortnightly, yielding 15 samples per trap and sampling year. Subsequently, the carabid beetles were determined to the species level according to Müller-Motzfeld (2004) by Thomas Kolling and Dirk Pflugmacher in 1999-2001 and by Fabio Weiss and Thomas Kolling in 2020-2022. The eleven study sites of this study were chosen as representative selection of managed and unmanaged beech forests of old stand age and comparable environmental site conditions. Two of the sites (Serrahn and Grumsin) have been declared UNESCO World Heritage Sites as part of the "Ancient and Primeval Beech Forests of the Carpathians and Other Regions of Europe"; two others (Heilige Hallen and Fauler Ort) represent the oldest known lowland beech forests without timber use in Germany. The majority of the sites (seven, including Grumsin) are part of the Schorfheide-Chorin Biosphere Reserve, while Serrahn is part of the Müritz National Park.

本数据集汇编了1999年至2001年，以及2020年至2022年在同一地点采用相同方法采集的步甲（Carabid beetles）调查数据。采样采用陷捕诱集法，诱捕装置为容积400毫升的蜂蜜罐，罐体带有延伸式PVC边缘盘。诱捕器被安置于PVC管材内部，并以金属顶盖遮蔽。每个诱捕器内盛放200毫升诱集液，为乙二醇与水按50%体积比配制的混合溶液。2020年至2022年期间，研究人员借助全球定位系统（GPS）定位数据与林木调查地图，将诱捕器位置精确定位至误差小于2米的范围内。所有采样时段均为每年4月中旬至11月上旬，诱捕器每两周清理一次，每个诱捕器每年可获取15份采样样本。随后，1999年至2001年的步甲样本由Thomas Kolling与Dirk Pflugmacher依据Müller-Motzfeld（2004）的分类标准鉴定至物种水平；2020年至2022年的样本则由Fabio Weiss与Thomas Kolling完成同类鉴定。本研究共选取11个样地，均为林龄较老的经营型与非经营型山毛榉林，且环境立地条件具有可比性。其中2个样地（Serrahn与Grumsin）作为"Ancient and Primeval Beech Forests of the Carpathians and Other Regions of Europe"的组成部分，被列入联合国教育、科学及文化组织（UNESCO）世界遗产名录；另外2个样地（Heilige Hallen与Fauler Ort）为德国已知最古老的未进行木材采伐的低地山毛榉林。多数样地（共7个，含Grumsin）属于Schorfheide-Chorin生物圈保护区，Serrahn则隶属于Müritz国家公园。