Effects of plant functional traits on soil stability: intraspecific variability matters

This data set describes different vegetation, soil and plant functional traits (PFTs) of 15 plant species in 30 sampling plots of an agricultural landscape in the Haean-myun catchment in South Korea. We divided the data set into two main tables, the first one includes the PFTs data of the 15 studied plant species, and the second one includes the soil and vegetation characteristics of the 30 sampling plots. For a total of 150 individuals, we measures the maximum plant height (cm) and leaf size (cm**2), which means the leaf surface area for the aboveground compartment of each individual. For the belowground compartment, we measured root horizontal width, which is the maximum horizontal spread of the root, rooting length, which is the maximum rooting depth, root diameter, which is the average root diameter of a the whole root, specific root length (SRL), which is the root length divided by the root dry mass, and root/shoot ratio, which is the root dry mass divided by the shoot dry mass. At each of the 30 studied plots, we estimated three different variables describing the vegetation characteristics: vegetation cover (i.e. the percentage of ground covered by vegetation), species richness (i.e. the number of observed species) and root density (estimated using a 30 cm x 30 cm metallic frame divided into nine 10 cm x 10 cm grids placed on the soil profile), as we calculated the total number of roots that appear in each of the nine grids and then we converted it into percentage based on the root count, following. Moreover, in each plot we estimated six different soil variables: Bulk density (g/cm**3), clay % (i.e. percentage of clay), silt % (i.e. percentage of silt), soil aggregate stability, using mean weight diameter (MWD), penetration resistance (kg/cm**2), using pocket penetrometer and soil shear vane strength (kPa).本数据集描述了韩国海安县流域（Haean-myun catchment）农业景观30个采样样地中15种植物的不同植被、土壤及植物功能性状（plant functional traits, PFTs）。本数据集被划分为两张主表：第一张表包含本次研究的15种植物的功能性状数据，第二张表涵盖30个采样样地的土壤与植被特征。针对总计150株植物个体，我们测定了其最大株高（单位：厘米）与叶面积（单位：平方厘米，即单株地上部分的叶表面积）。对于地下部分，我们测定了根幅（即根系的最大水平扩展范围）、根长（即最大生根深度）、平均根直径（即整个根系的平均直径）、比根长（specific root length, SRL，即根长与根干重的比值）以及根冠比（即根干重与地上部分干重的比值）。在30个研究样地中，我们估算了三类表征植被特征的变量：植被盖度（即植被覆盖地面的百分比）、物种丰富度（即观测到的植物物种数量），以及根密度：采用尺寸为30 cm×30 cm的金属框架，将其划分为9个10 cm×10 cm的网格并放置于土壤剖面，统计9个网格中出现的根系总数量，随后基于根系计数将其转换为百分比占比。此外，在每个样地中我们还测定了六类土壤变量：容重（单位：g/cm³）、黏粒百分比（即黏土颗粒占比）、粉粒百分比（即粉砂颗粒占比）、以平均重量直径（mean weight diameter, MWD）表征的土壤团聚体稳定性、采用袖珍贯入仪测定的穿透阻力（单位：kg/cm²），以及以千帕（kPa）为单位的土壤十字板剪切强度。