H. J. Andrews Experimental Forest site, station Andrews Watershed 3, study of cover of bare ground in units of percent on a yearly timescale

The EcoTrends project was established in 2004 by Dr. Debra Peters
(Jornada Basin LTER, USDA-ARS Jornada Experimental Range) and
Dr. Ariel Lugo (Luquillo LTER, USDA-FS Luquillo Experimental Forest)
to support the collection and analysis of long-term ecological datasets.
The project is a large synthesis effort focused on improving the accessibility
and use of long-term data. At present, there are ~50 state and federally funded
research sites that are participating and contributing to the EcoTrends project,
including all 26 Long-Term Ecological Research (LTER) sites and sites funded by
the USDA Agriculture Research Service (ARS), USDA Forest Service,
US Department of Energy, US Geological Survey (USGS) and numerous universities. Data from the EcoTrends project are available through an exploratory web portal
(http://www.ecotrends.info). This web portal enables the continuation of data
compilation and accessibility by users through an interactive web application.
Ongoing data compilation is updated through both manual and automatic
processing as part of the LTER Provenance Aware Synthesis Tracking
Architecture (PASTA). The web portal is a collaboration between the Jornada LTER
and the LTER Network Office. The following dataset from H. J. Andrews Experimental Forest (AND)
contains cover of bare ground measurements in percent units
and were aggregated to a yearly timescale.

生态趋势（EcoTrends）项目于2004年由黛布拉·彼得斯博士（霍德纳斯盆地长期生态研究站Long-Term Ecological Research, LTER、美国农业部农业研究局USDA-ARS霍德纳斯实验牧场）与阿里尔·卢戈博士（卢奎洛长期生态研究站Long-Term Ecological Research, LTER、美国农业部林务局USDA-FS卢奎洛实验森林）发起成立，旨在支持长期生态数据集的收集与分析工作。本项目为大型综合研究计划，致力于提升长期生态数据的可获取性与应用价值。目前，共有约50个州级与联邦资助的研究站点参与并为生态趋势项目贡献数据，其中涵盖全部26个长期生态研究（Long-Term Ecological Research, LTER）站点，以及由美国农业部农业研究局ARS、美国农业部林务局、美国能源部、美国地质调查局USGS与众多高校资助的研究站点。生态趋势项目的数据可通过探索式网络门户（http://www.ecotrends.info）获取，该门户依托交互式网页应用，支持用户持续开展数据汇编与数据获取工作。此项持续推进的数据汇编工作，通过人工与自动结合的处理流程进行更新，该流程隶属于长期生态研究溯源感知综合跟踪架构（Provenance Aware Synthesis Tracking Architecture, PASTA）。本网络门户由霍德纳斯LTER站与LTER网络办公室联合共建。以下来自H·J·安德鲁斯实验林（AND）的数据集，包含以百分比为单位的裸地覆盖率测量数据，并已按年尺度完成聚合。