《Table 1 Basic soil properties at the depth of 0–200 cm in 2002 (before seeding)》

  提示：宽带有限、当前游客访问压缩模式

本系列图表出处文件名：随高清版一同展现

《"Hierarchical responses of soil organic and inorganic carbon dynamics to soil acidification in a dryland agroecosystem,China"》

1. 获取 高清版本忘记账户？点击这里登录

1. 下载图表忘记账户？点击这里登录

Note:SOC，soil organic carbon；SIC，soil inorganic carbon；BD，bulk density.

The experiment was performed as a complete random block design with a total of nine experimental plots（6.6 m×9.9 m for each plot）.A monoculture of winter wheat（Triticum aestivum）was planted in this area from 2002 to 2014.The N fertilizer application experiments with three N levels（N0，0 kg N/ （hm2·a）；N120，120 kg N/（hm2·a）；N240，240 kg N/（hm2·a）） were initiated in October 2002.The three N application levels represent the control level（without chemical N application），recommended level（the optimal N fertilizer application rate after a soil test）and projected level（the level that the farmers may apply in the future），respectively.For each plot，the phosphate fertilizer was applied at a rate of 100 kg P2O5/hm2.Superphosphate（P2O5>16%）and urea（N>46%）were applied as the phosphate and N，respectively.No potash fertilizer was applied.In early October of each year，all fertilizers in each plot were plowed thoroughly to a soil depth of 30 cm.Then，the winter wheat seeds（150 kg/hm2）were sown by a machine（after 2006），with 30 rows in each plot.All other field managements were followed the adopted practices locally.Finally，the wheat yield was measured in the mid-June of the following year.The original soil properties at the 0–20 cm soil depth in 2002（before seeding）can be referred to Wang et al.（2014）.Table 1 presents the values of SOC content，SIC content，soil p H and soil bulk density at the depth of 0–200 cm in October 2002.Briefly，soil samples were collected using a soil auger（4 cm in diameter）at an interval of 20 cm depth.SOC content was measured using wet combustion with K2Cr2O7；SIC content was measured by the manometric collection of CO2 evolved with an HCl treatment process；soil bulk density was measured using the oven-dry method to the soil mass and the core volume；and soil p H was measured using a p H meter（PHS-3C）on a 1:5 soil:water extract.