Data from: Precipitation, soils, NPP, and biodiversity: resurrection of Albrecht's Curve

Climate and soils are widely recognized as major drivers of virtually all properties of ecosystems and communities. However, despite major advances in the understanding of soil formation and ecosystem dynamics, the effects of climate on soil properties are not widely appreciated. Understanding the effects of water availability on the rates of chemical and biological processes that affect soil formation can help clarify the global patterns of soil fertility, which affect agricultural and forest productivity, as well as biodiversity. Empirical tests of Albrecht's conceptual model of soil development and degradation using global climate and soil datasets and soil chronosequences confirm that soil total exchangeable bases (TEB), phosphorus, nitrogen and other components of soil fertility, along with plant productivity generally decline on older soils and under wetter conditions as precipitation exceeds potential evapotranspiration. The basic pattern of soil fertility in relation to water availability is a unimodal curve, with a maximum near or below a water balance of zero (annual precipitation - annual potential evapotranspiration). Analysis of global data by sub-regions reveals significant differences between temperate and tropical soil fertility distributions, as well as significant differences between continents. The low levels of soil nutrients (e.g., TEB, P, N) and plant productivity found on ancient soils or highly weathered soils in regions with high precipitation suggest that the positive effects of low productivity on plant diversity that have been observed at local and regional scales may also occur at the global scale.,Linux gzip tar file with large datafilesFilestoDryad.tar.gz,

气候与土壤被广泛认为是驱动生态系统与群落几乎所有属性的核心因素。尽管学界在土壤形成与生态系统动态的研究上已取得重大进展，但气候对土壤属性的影响却尚未得到广泛认知。厘清水分有效性对调控土壤形成的化学与生物过程速率的影响，有助于阐明土壤肥力的全球分布格局——这一格局同时影响农业与森林生产力，以及生物多样性。依托全球气候与土壤数据集、土壤时间序列（soil chronosequences）对阿尔布雷希特土壤发育与退化概念模型开展的实证检验证实：随着降水超过潜在蒸散量，在老旧土壤以及湿润环境中，土壤总交换性碱基（total exchangeable bases, TEB）、磷、氮等土壤肥力组分，以及植物生产力普遍呈现下降趋势。土壤肥力随水分有效性变化的基本模式呈单峰曲线，峰值出现在水分平衡值（年降水量-年潜在蒸散量）为零或略低于零的区间。对全球数据按子区域开展的分析显示，温带与热带的土壤肥力分布存在显著差异，不同大洲之间亦存在显著差异。在高降水区域的古老土壤或高度风化土壤中，土壤养分（如TEB、磷、氮）与植物生产力水平普遍偏低，这表明在局地与区域尺度上观测到的低生产力对植物多样性的正向效应，在全球尺度上同样可能存在。内含大型数据文件的Linux gzip压缩tar归档文件：FilestoDryad.tar.gz