A simple model to predict soil penetrometer resistance as a function of density, drying and depth in the field
A simple model to predict soil penetrometer resistance as a function of density, drying and depth in the field
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DOI：
10.1016/j.still.2015.08.004
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发表时间：
2016-01-01
影响因子：
6.5
通讯作者：
Ren, Tusheng
中科院分区：
文献类型：
--
作者：
Gao, Weida;Whalley, W. Richard;Ren, Tusheng
针入阻力是决定根系伸长和产量的重要土壤物理性质之一。采用田间试验研究了东北黑土区免耕和垄作对土壤容重、基质势和深度对土壤容重计阻力的影响。田间试验于2010年秋季在粘壤土上开始。在2012年和2013年玉米生长季节测定了土壤容重、含水量、水分释放曲线和土壤容重计阻力。与RI处理相比，NT处理显著提高了0-20 cm土层土壤容重，降低了大孔隙率。NT下密度的增加导致了更高的土壤水分计阻力，这是与较低的根系吸水相比，RI处理。可以用一个相对简单的土壤容重、水分状况和深度对土壤容重计阻力的影响模型来解释。通过将深度与上覆岩层压力相关联，将其包括在内。在排除上覆岩层压力或深度的电阻率计电阻模型中，无法准确拟合较深层（>35 cm）的电阻率计电阻。本研究中深度对贯入仪阻力的影响与已发表的数据一致。我们的数据表明，在评估根系生长的土壤条件时，忽略深度的影响可能会产生误导性的土壤电阻。(C)2015 Elsevier B. V.版权所有。
Penetrometer resistance is one of the important soil physical properties that can determine, or be strongly correlated with, both root elongation and yield. We used a field experiment, which was designed to explore the effects of no-tillage (NT) and ridge tillage (RT) on a Mollisols in Northeast China, to test an approach for predicting the effects of soil bulk density, matric potential of water, and depth on penetrometer resistance. The field experiment was initiated in the fall 2010 on a clay loam soil. Soil bulk density, water content, water release curve, and penetrometer resistance were measured during the corn growing seasons in 2012 and 2013. Compared with the RI treatment, NT significantly increased soil bulk density and reduced the fraction of macropores in the 0-20 cm soil layer. The increase in density under NT resulted in a higher soil penetrometer resistance, which was associated with a lower water uptake by roots compared with the RI treatment. It was possible to use a relatively simple model for penetrometer resistance to explain the effects of soil bulk density, water status and depth on penetrometer resistance. Depth was included by relating it to overburden pressure. In a penetrometer resistance model that excluded overburden pressure, or depth empirically, penetrometer resistance in deeper layers (>35 cm) could not be fitted accurately. The effects of depth on penetrometer resistance from this study were consistent with published data. Our data suggests that at the assessment of soil conditions for root growth, ignoring the effects of depth is likely to give misleading penetrometer resistance. (C) 2015 Elsevier B.V. All rights reserved.