Grazinglands Research Laboratory site, station NADP Station OK17, Kessler Farm Field Laboratory, OK, study of nitrogen from nitrate in precipitation (volume-weighted concentration) in units of milligramsPerLiter on a monthly 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 Grazinglands Research Laboratory (GRL)
contains nitrogen from nitrate in precipitation (volume-weighted concentration) measurements in milligramsPerLiter units
and were aggregated to a monthly timescale.

EcoTrends项目（EcoTrends）于2004年由黛布拉·彼得斯博士（约纳盆地长期生态研究站点（Jornada Basin LTER），美国农业部农业研究局约纳实验牧场）与阿里尔·卢戈博士（卢奎约长期生态研究站点（Luquillo LTER），美国农业部森林服务局卢奎约实验林）创立，旨在支持长期生态数据集的收集与分析工作。
该项目为大型综合研究计划，核心目标是提升长期生态数据的可获取性与应用效能。目前共有约50个州级与联邦资助的研究站点参与并向EcoTrends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服务局（USDA Agricultural Research Service, ARS）、美国农业部森林服务局、美国能源部、美国地质调查局（US Geological Survey, USGS）与众多高校资助的研究站点。
EcoTrends项目的数据可通过探索性网络门户（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。作为长期生态研究站点溯源感知综合跟踪架构（Provenance Aware Synthesis Tracking Architecture, PASTA）的组成部分，其持续的数据汇编流程通过手动与自动两种处理方式完成更新。
该网络门户由约纳LTER与LTER网络办公室联合开发。本数据集源自牧场研究实验室（Grazinglands Research Laboratory, GRL），包含以毫克每升为单位的降水中硝酸盐氮（体积加权浓度）实测数据，且已聚合至月尺度。