Baltimore Ecosystem Study LTER site, station Pond Branch (USGS 01583570), study of nitrogen from nitrate in streamwater in units of milligramsPerLiter 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 Baltimore Ecosystem Study LTER (BES)
contains nitrogen from nitrate in streamwater measurements in milligramsPerLiter units
and were aggregated to a yearly timescale.

EcoTrends项目由德布拉·彼得斯博士（约拿盆地长期生态研究站[Jornada Basin LTER]，美国农业部农业研究服务局[USDA Agricultural Research Service，ARS]约拿实验牧场）与阿里尔·卢戈博士（卢奎洛长期生态研究站[Luquillo LTER]，美国农业部森林服务局[USDA Forest Service]卢奎洛实验林）于2004年创立，旨在支撑长期生态数据集的采集与分析工作。
本项目为大型综合研究计划，核心聚焦于提升长期数据的可获取性与应用价值。截至目前，共有约50个由州政府与联邦政府资助的研究站点参与EcoTrends项目并贡献数据，其中涵盖全部26个长期生态研究（Long-Term Ecological Research，LTER）站点，以及美国农业部农业研究服务局、美国农业部森林服务局、美国能源部、美国地质调查局（United States Geological Survey，USGS）与众多高校资助的研究站点。
EcoTrends项目的数据集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访问工作。
作为长期生态研究溯源感知综合跟踪架构（Provenance Aware Synthesis Tracking Architecture，PASTA）的组成部分，持续推进的数据汇编工作通过手动与自动两种处理方式完成更新。本网络门户由约拿LTER与LTER网络办公室联合开发。
以下来自巴尔的摩生态系统研究长期生态研究站（Baltimore Ecosystem Study LTER，BES）的数据集，包含以毫克每升为单位的溪流水中硝酸盐氮含量实测数据，且已按年度时间尺度进行聚合。