Soil water content and water salinity (DP1.00094.001)

Soil volumetric water content and an index of soil water ion content (salinity) are measured at various depths below the soil surface from approximately 6 cm down to 200 cm at non-permafrost sites (down to 300 cm at Alaskan sites). Soil moisture is an important component of the hydrologic cycle and is the dominant source of water for most plants and soil organisms making it a key indicator of drought. In addition, soil moisture status influences the severity of flooding and temperature extremes, as well as physical, chemical and biological processes in the soil. Measurements are made in vertical profiles consisting of up to eight depths in all five instrumented soil plots at each terrestrial site, and presented as 1-minute and 30-minute averages. Soil moisture sensors cannot accurately measure frozen water, therefore soil water content values will be absent or flagged if the soil was frozen or corresponding soil temperature data were not available to perform this test.

Latency:
Data collected in any given month are published during the second full week of the following month.

This data product is not currently available at the PUUM site (Hawaii) due to the initial soil characterization indicating the soil was too shallow to allow the standard sensor to be installed. An alternative sensor was installed, but it is not currently compatible with the data processing pipeline. Future upgrades to the data processing pipeline will allow the data product to be produced, including retroactively, but this is not expected to occur soon. In the interim, raw sensor data are available upon request via the NEON Contact Form, but have not undergone any quality control, quality assurance, or data flagging.

本数据集测量了非永久冻土区域（阿拉斯加站点可至地下300厘米）从约6厘米至200厘米的不同土壤深度的土壤体积含水量（soil volumetric water content），以及土壤水离子含量指数——盐度（salinity）。
土壤水分是水文循环的重要组成部分，亦是多数植物与土壤生物的主要水源，因此是干旱状况的关键指示因子。此外，土壤水分状况还会影响洪涝与极端气温事件的严重程度，以及土壤内部的物理、化学与生物过程。
测量工作在每个陆地站点的全部5个布设仪器的土壤样地中开展，采样垂直剖面最多包含8个深度层级，最终数据以1分钟与30分钟平均值的形式发布。
由于土壤水分传感器无法准确测量冻结状态的水分，若土壤处于冻结状态，或缺乏用于执行该检测的对应土壤温度数据，则土壤含水量数值将缺失或被标记异常。

数据发布延迟说明：
当月采集的数据将于次月的第二个完整工作周内发布。

目前PUUM站点（夏威夷）暂未提供本数据产品，原因是初始土壤特性表征结果显示该区域土壤过浅，无法安装标准传感器。虽已安装替代传感器，但当前其与数据处理流水线尚不兼容。未来将对数据处理流水线进行升级以支持该数据产品的生成（包括回溯生成历史数据），但预计短期内无法实现。在此期间，用户可通过NEON联系表单申请获取原始传感器数据，但该类数据未经过任何质量控制、质量保证与数据标记流程。