西南喀斯特地区典型土壤退化过程中金属的腐蚀规律与机理研究

Karst regions are typically fragile ecological environment zones，most widely distributed in Southwestern of China. The water and soil loss in Southwestern karst regions of China is serious，leading to serious soil degradation. The essence of soil degradation in the karst regions is the soil erosion under hydraulic effects..Many researches have been conducted on the harmfulness of soil degradation in karst regions. However, there are no related reports about the laws of material corrosion in the process of soil degradation. From laboratory simulation experiments and field tests, metal corrosion test apparatus in the process of soil degradation in Southwestern karst regions of China and models of soil degradation will be established, the laws of metal corrosion rate in the process of soil degradation caused by many different factors such as soil slope, rainfall capacity, components of acid rain, amount of acid deposition will be studied. The aim of the project is to study the macro cell corrosion caused by different mineral compositions and different content in soil degradation stages in karst regions, as well as the mechanism of metallic material corrosion caused by sulfate-reducing bacteria in soil degradation process.The key factors that control metal corrosion will be acquired.The law of material corrosion in karst regions during the process of soil degradation will be understood,the corrosion mechanism models of metal materials will be established, so that the scientific basis for corrosion and protection in karst areas can be provided.

喀斯特地区是典型的生态环境脆弱区，我国西南是喀斯特面积最大、分布最广的地区。西南喀斯特地区水土流失严重，导致严重的土壤退化，喀斯特地区土壤退化的实质是在水力作用下土壤的侵蚀退化过程。. 科研工作者对喀斯特地区土壤退化的危害性进行了大量的研究，但关于土壤退化过程中材料腐蚀规律的研究目前尚无相关报道。本项目通过实验室模拟试验、现场埋藏试验，建立西南喀斯特地区土壤退化金属腐蚀试验装置以及土壤退化模型，研究不同的土壤坡度、降雨量、酸雨组份和酸沉降量导致的土壤退化过程中金属腐蚀速率的变化规律，以及土壤不同退化阶段土壤矿物组成及其含量的变化引起的宏电池腐蚀，探讨土壤退化过程中硫酸盐还原菌等微生物对金属的腐蚀机理，确定该地域条件控制金属腐蚀的关键因素，可以更清楚地了解喀斯特地区土壤退化过程中材料的腐蚀规律，提出土壤退化过程中材料腐蚀机理模型，以便为喀斯特地区土壤中金属的腐蚀与防护提供科学依据。

土壤环境中金属腐蚀问题的研究是腐蚀研究领域的重要方面。喀斯特地区是一个具有环境容量低、生态环境系统变异敏感度高和稳定性差等一系列生态脆弱性特征的区域。其中，我国西南是喀斯特面积最大、分布最广的地区。土壤退化过程中，土壤会发生一系列复杂的变化，从而影响金属在土壤中腐蚀行为。因此，研究土壤退化过程中金属腐蚀具有重要的意义。本项目题研究了西南喀斯特地区典型土壤退化过程中金属材料的腐蚀规律，取得了一些重要的实验数据，以便为喀斯特地区土壤中金属的腐蚀与防护提供参考。