LBA-ECO ND-10 Soil Properties of Pasture Chronosequences, Para, Brazil: 1997

This data set provides the results of soil physical property and chemical measurements of samples collected from two pasture chronosequences (years since conversion from primary forest) located on two ranches south of Santarem, Para, Brazil, and east of the Tapajos River. Soil data includes soil classification, bulk density, texture, and mean concentrations of total nitrogen (N), carbon (C), phosphorus (P), and P fractions. The soils were high clay oxisols and highly sandy entisols.

One chronosequence of sites was established on oxisol soils dating 2, 7, and 15 years since conversion from primary forest. A second set of sites, 1, 7, and 15 years old was established on the sandy entisols. Five of the six pasture sites were on a single ranch; the 2-year-old oxisol pasture was the exception. Ten soil samples per site were collected from 0-10 cm depth along random intervals within 100-m transects in August 1997.

There are two comma-delimited (.csv) data files with this data set.

本数据集提供了采自巴西帕拉州圣塔伦以南、塔帕若斯河东侧两处牧场的两处草地演替序列（pasture chronosequences，即原生林转换为草地后的年限）的土壤物理性质与化学属性测定结果。土壤数据涵盖土壤分类、土壤容重（bulk density）、土壤质地（soil texture），以及全氮（N）、全碳（C）、全磷（P）及其各磷组分（P fractions）的平均浓度。供试土壤包含高黏型氧化土（Oxisols）与高砂型新成土（Entisols）两类。

其中一处演替序列设置于氧化土上，对应草地自原生林转换后的年限分别为2年、7年和15年；另一处序列设置于砂质新成土上，对应草地年限为1年、7年和15年。六处草地样地中有五处位于同一牧场，仅2年生氧化土草地样地为例外。1997年8月，研究人员于每个样地内沿100米样带的随机间隔处采集0~10 cm深度的土壤样品，每个样地采集10份。

本数据集包含两个以逗号分隔的CSV格式数据文件。