United Kingdom Butterfly Monitoring Scheme: species trends 2020

This dataset provides linear trends, over varying time periods, for the Collated Indices of individual butterfly species across the UK. The main statistical values derived from a linear regression (slope, standard error, P-value) are presented for the entire time series for each species (1976# to the present year), for the last 20 years, and for the last decade. In addition, trends are classified based on the direction and significance of a linear slope together with an estimated percentage change for that time period. These trend data are provided for all UK butterfly species for which we have sufficient data (58 species). Trends are calculated by performing a linear regression on the annual Collated indices for each species. Collated indices are calculated using a log-linear model incorporating individual site indices from all monitored sites across the UK for a given species in a given year. This dataset provides linear trends, over varying time periods, for the Collated Indices of individual butterfly species across the UK. The main statistical values derived from a linear regression (slope, standard error, P-value) are presented for the entire time series for each species (1976# to the present year), for the last 20 years, and for the last decade. In addition, trends are classified based on the direction and significance of a linear slope together with an estimated percentage change for that time period. These trend data are provided for all UK butterfly species for which we have sufficient data (58 species). Trends are calculated by performing a linear regression on the annual Collated indices for each species. Collated indices are calculated using a log-linear model incorporating individual site indices from all monitored sites across the UK for a given species in a given year. Trends across different time series allow us to determine the long and short-term status of individual species. This is enables us to focus conservation and research and also to assess species responses to conservation already in place. The UK Butterfly Monitoring Scheme is organized and funded by Butterfly Conservation (BC), the UK Centre for Ecology & Hydrology (UKCEH), the British Trust for Ornithology (BTO), and the Joint Nature Conservation Committee (JNCC). The UKBMS is indebted to all volunteers who contribute data to the scheme. This work was supported by the Natural Environment Research Council award number NE/R016429/1 as part of the UK-SCAPE programme delivering National Capability. #Because the Collated indices are only calculated for each species in years in which it was recorded on five or more sites, the starting year for the series is later than 1976 for a number of rarer species. Full details about this dataset can be found at https://doi.org/10.5285/236ee6bd-2330-4f84-a871-5a8ebe1925b5本数据集提供了英国境内各蝴蝶物种汇总指数（Collated Indices）在不同时长时间段内的线性变化趋势。针对每个物种，我们给出了基于完整时间序列（1976年至今，部分稀有物种起始年份晚于1976年，详见文末注释）、近20年以及近10年的线性回归（linear regression）分析结果，涵盖斜率、标准误、P值等核心统计量。此外，我们会根据线性斜率的方向与显著性，结合对应时间段内的预估百分比变化，对种群趋势进行分类。本数据集涵盖了数据量充足的全部58种英国蝴蝶物种。 种群趋势的计算基于各物种的年度汇总指数开展线性回归分析。而年度汇总指数则通过对数线性模型（log-linear model）计算得出，该模型整合了给定年份、给定物种在英国所有监测站点的单点指数数据。 不同时间尺度的趋势数据可用于研判各物种的长短期种群状况，从而为针对性保护与研究工作提供支撑，同时也可用于评估现有保护措施对物种的影响效果。 本数据集源自英国蝴蝶监测计划（UK Butterfly Monitoring Scheme, UKBMS），该计划由蝴蝶保护协会（Butterfly Conservation, BC）、英国生态与水文中心（UK Centre for Ecology & Hydrology, UKCEH）、英国鸟类学信托基金会（British Trust for Ornithology, BTO）以及联合自然保护委员会（Joint Nature Conservation Committee, JNCC）组织并资助。英国蝴蝶监测计划对所有为本计划贡献数据的志愿者致以衷心感谢。本研究得到了自然环境研究委员会项目编号NE/R016429/1的资助，作为英国SCAPE计划（delivering National Capability，交付国家能力）的一部分开展。 # 由于仅当某物种在当年被至少5个监测站点记录到时，才会计算其汇总指数，因此部分稀有物种的时间序列起始年份晚于1976年。 本数据集的完整详细信息可通过以下链接获取：https://doi.org/10.5285/236ee6bd-2330-4f84-a871-5a8ebe1925b5