...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Earth Surface Processes and Landforms: The journal of the British Geomorphological Research Group >Modelling increased soil cohesion due to roots with EUROSEM
【24h】

Modelling increased soil cohesion due to roots with EUROSEM

机译：用EUROSEM模拟由于根部增加的土壤内聚力

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

As organic root exudates cause soil particles to adhere firmly to root surfaces, roots significantly increase soil strength and therefore also increase the resistance of the topsoil to erosion by concentrated flow. This paper aims at contributing to a better prediction of the root effects on soil erosion rates in the EUROSEM model, as the input values accounting for roots, presented in the user manual, do not account for differences in root density or root architecture. Recent research indicates that small changes in root density or differences in root architecture considerably influence soil erosion rates during concentrated flow. The approach for incorporating the root effects into this model is based on a comparison of measured soil detachment rates for bare and for root-permeated topsoil samples with predicted erosion rates under the same flow conditions using the erosion equation of EUROSEM. Through backwards calculation, transport capacity efficiencies and corresponding soil cohesion values can be assessed for bare and root-permeated topsoils respectively. The results are promising and present soil cohesion values that are in accordance with reported values in the literature for the same soil type (silt loam). The results show that grass roots provide a larger increase in soil cohesion as compared with tap-rooted species and that the increase in soil cohesion is not significantly different under wet and dry soil conditions, either for fibrous root systems or for tap root systems. Power and exponential relationships are established between measured root density values and the corresponding calculated soil cohesion values, reflecting the effects of roots on the resistance of the topsoil to concentrated flow incision. These relationships enable one to incorporate the root effect into the soil erosion model EUROSEM, through adapting the soil cohesion input value. A scenario analysis shows that the contribution of roots to soil cohesion is very important for preventing soil loss and reducing runoff volume. The increase in soil shear strength due to the binding effect of roots on soil particles is two orders of magnitude lower as compared with soil reinforcement achieved when roots mobilize their tensile strength during soil shearing and root breakage. Copyright (c) 2008 John Wiley & Sons, Ltd.
机译：由于有机根系分泌物使土壤颗粒牢固地附着在根系表面上，因此根系显着提高了土壤强度，因此也增加了表层土壤对浓流侵蚀的抵抗力。本文旨在通过EUROSEM模型更好地预测根系对土壤侵蚀速率的影响，因为用户手册中介绍的根系输入值不考虑根系密度或根系结构的差异。最近的研究表明，在集中流动期间，根系密度的微小变化或根系结构的差异会大大影响土壤侵蚀速率。将根效应纳入该模型的方法是基于使用EUROSEM侵蚀方程，比较在相同流动条件下裸土和根渗透表土样品的测得土壤脱附率与预测侵蚀率。通过反向计算，可以分别评估裸露和根系渗透表层土的运输能力效率和相应的土壤内聚力值。结果是令人鼓舞的，并且目前的土壤内聚力值与文献中针对相同土壤类型（粉壤土）的报道值一致。结果表明，与自生根种相比，草根在土壤内聚力上的增加更大，并且在湿和干土壤条件下，无论是对于纤维根系还是对于自来根系，土壤内聚力的增加没有显着差异。在测得的根系密度值和相应的计算的土壤内聚力值之间建立了幂和指数关系，反映了根系对表土对集中流切口的抵抗力的影响。这些关系使人们能够通过调整土壤内聚力输入值，将根效应纳入土壤侵蚀模型EUROSEM中。情景分析表明，根对土壤内聚力的贡献对于防止土壤流失和减少径流量非常重要。与根在土壤剪切和断根过程中动员其抗张强度时所获得的土壤增强作用相比，由于根对土壤颗粒的结合作用所致的土壤抗剪强度增加要低两个数量级。版权所有（c）2008 John Wiley＆Sons，Ltd.

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号