Soil physical and chemical properties, periodic (DP1.10086.001)

This data product contains the quality-controlled, native sampling resolution data from NEON's periodic soil sampling, as well as measurements of pH, moisture, chemistry, and stable isotopes. Samples collected as part of this product are also used for microbial measurements; those data can be found in associated data products.

Soil is defined as the upper layer of the earth's surface where plants grow and consists of decomposing organic material and inorganic particles such as clay and rock. Soils are sampled by horizon type (organic or mineral) to a maximum depth of 30cm. This depth was chosen to capture dynamics in the upper layers of the subsoil or B horizon along with the topsoil, and to match the sampling depth used in the Root biomass and chemistry, periodic data product (DP1.10067.001 ). Following field collection, all soils are measured for moisture and pH, and a subset are also measured for microbial abundance and composition, inorganic nitrogen (N) pools and net transformation rates, and total soil organic carbon (C) and nitrogen (N) concentrations and stable isotopes by external laboratories. Frozen soil for the microbial archive is also collected for many samples, and during peak greenness chemistry bouts, excess air-dried soil is archived in the NEON Biorepository and available upon request. For additional details, see the user guides, protocols, and science designs listed in the Documentation section below. Queries for this data product will return field collection metadata as well as physical and chemical measurements for the specified sites within the specified date range. Summary tables of external lab precision and accuracy for chemistry and stable isotope analyses are included in the expanded package. This data product also provides field and laboratory metadata that can be associated with soil microbial data products; refer to the documentation for the respective soil microbe data products for more details.

Latency:
The expected time from data and/or sample collection in the field to data publication is as follows, for each of the data tables (in days) in the downloaded data package. See the Data Product User Guides for more information.

sls_bgcSubsampling: 60

sls_metagenomicsPooling: 45

sls_soilCoreCollection: 35

sls_soilMoisture: 60

sls_soilpH: 90

sls_soilChemistry: 200

bgc\_CNiso\_externalSummary: 30

ntr_internalLab: 45

ntr_internalLabBlanks: 45

ntr_externalLab: 180

ntr_externalSummary: 30

本数据产品包含经过质量控制、保留原生采样分辨率的美国国家生态观测站网络（NEON）周期性土壤采样数据，以及pH值、土壤湿度、化学组分与稳定同位素的测定结果。本产品采集的土壤样本同时用于微生物相关测定，相关数据可在关联数据产品中获取。

本数据集所定义的土壤，指地球表面供植物生长的表层，由分解有机质与黏土、岩石等无机颗粒组成。土壤采样按发生层类型（有机质层或矿质层）进行，最大采样深度为30厘米。该采样深度的选取原则为：同时捕捉亚表层（B层）与表层土壤的动态变化，并与《根系生物量与化学组分 周期性数据产品（DP1.10067.001）》采用的采样深度保持一致。野外采集完成后，所有土壤样品均会测定湿度与pH值；另有部分样品会送至外部实验室，开展微生物丰度与群落组成、无机氮库与净转化速率、总土壤有机碳（C）与总氮（N）浓度及稳定同位素分析。针对多数样品，还会采集用于微生物存档的冷冻土壤样本；在植被盛绿期的化学采样批次中，多余的风干土壤样品会存入NEON生物样本库，可按需申请调取。更多细节请参阅下文“文档”部分所列的用户指南、实验规程与科学设计方案。查询本数据产品时，将返回指定站点、指定日期范围内的野外采集元数据，以及土壤的物理与化学测定结果。扩展数据包中包含了化学分析与稳定同位素测定的外部实验室精密度与准确度汇总表。本数据产品还提供可与土壤微生物数据产品关联的野外与实验室元数据；如需了解更多细节，请参阅对应土壤微生物数据产品的文档。

数据延迟说明：
下载数据包中各数据表从野外数据和/或样本采集到正式发布的预期时长（单位：天）如下，更多信息请参阅《数据产品用户指南》。
sls_bgcSubsampling：60
sls_metagenomicsPooling：45
sls_soilCoreCollection：35
sls_soilMoisture：60
sls_soilpH：90
sls_soilChemistry：200
bgc_CNiso_externalSummary：30
ntr_internalLab：45
ntr_internalLabBlanks：45
ntr_externalLab：180
ntr_externalSummary：30