SGS-LTER East Pawnee National Grassland - Keota North Toposequence 2003

EPNG Keota North Toposequence - The Keota North toposequence was selected for its silty parent material (silty member of White River Formation?), and is one of a set of toposequences representing silty, clayey and sandy parent materials on the PNG that will allow us to investigate ecological phenomena across topographic and texture gradients. Six pedons were described at the following landscape positions: summit, shoulder, backslope, footslope, toeslope, floodplain. Samples were analyzed at the National Soil Survey Laboratory, Lincoln, Nebraska. Analyses included: particle size (including fractionation of sand, silt and clay); total N; dithionate-citrate extractable Fe, Mn and Al; CEC; bulk density; available H2O; sand, silt and clay mineralogy.

EPNG科奥塔北部地形序列——本研究选取科奥塔北部地形序列（toposequence），因其母质为粉砂质（疑为怀特河组（White River Formation）粉砂质段），该序列是代表巴布亚新几内亚（PNG）境内粉砂质、黏质及砂质母质的一组地形序列之一，可用于探究地形与质地梯度下的各类生态现象。本次研究共在如下景观位置设置并描述了6个土壤单体（pedon）：山脊顶、坡肩、坡背、坡足、坡趾、河漫滩。样品分析工作在内布拉斯加州林肯市的国家土壤调查实验室（National Soil Survey Laboratory）完成，分析项目包括：颗粒组成（含砂、粉粒、黏粒分级）、全氮、连二亚硫酸钠-柠檬酸盐提取态铁、锰、铝、阳离子交换量（CEC）、容重、有效持水量，以及砂粒、粉粒、黏粒矿物组成。