California Current Ecosystem site, station Orange County, CA (FIPS 6059), study of human population density in units of numberPerKilometerSquared 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 California Current Ecosystem (CCE)
contains human population density measurements in numberPerKilometerSquared units
and were aggregated to a yearly timescale.

EcoTrends项目（EcoTrends project）于2004年由黛布拉·彼得斯博士（约尔纳达盆地长期生态研究站[Long-Term Ecological Research, LTER]，美国农业部农业研究局约尔纳达实验牧场）与阿里尔·卢戈博士（卢奎洛长期生态研究站[Long-Term Ecological Research, LTER]，美国农业部林务局卢奎洛实验森林）创立，旨在支撑长期生态数据集的收集与分析工作。
该项目为一项大型综合研究计划，核心目标是提升长期生态数据的可获取性与使用效率。
目前共有约50个由州政府及联邦政府资助的研究站点参与并为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局（Agricultural Research Service, ARS）、美国农业部林务局、美国能源部、美国地质调查局（United States Geological Survey, USGS）与众多高校资助的各类站点。
EcoTrends项目的数据可通过探索性网络门户（http://www.ecotrends.info）获取。该网络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将通过手动与自动处理相结合的方式完成更新。
该网络门户是约尔纳达LTER与LTER网络办公室的合作成果。
以下来自加州洋流生态系统（California Current Ecosystem, CCE）的数据集包含以每平方千米人口数为单位的人口密度测量数据，且已被聚合至年度时间尺度。