利用探地雷达技术对河西杨根系影响甘肃高台明长城遗址的研究

植物根系的生长和腐烂对土遗址具有不同程度的破坏作用,影响其长久保存。为确定明代长城土遗址本体内树木根系的生长分布情况,本研究利用探地雷达技术,对甘肃高台境内的明代长城遗址内生长的河西杨根系进行了探测研究。结果表明:河西杨根系主要分布于探测区域北侧,并由北向南延伸,周围分布有侧根,根系主要分布在深度为35~85cm范围内,主根直径约为12cm。400MHz天线的探测深度可达2m,而900MHz天线具有较高的探测精度,二者结合使用可更好地判断地下根系的生长情况。本研究首次获得遗址内根系三维图像,并在不破坏土遗址结构的前提下,确定了树木根系的分布状况。该技术为长城遗址保护方案的制定和加固修复措施的开展提供了重要的科学依据。

A study of the impact of Populus gansuensis roots on ruins of the Ming Dynasty Great Wall at Gaotai, Gansu province using ground penetrating radar

The growth and decay of plant root systems can have destructive effects on earthen heritage sites, challenging permanent conservation of those precious sites. In this study, ground penetrating radar was used to detect the root systems of Populus gansuensis in ruins of the Ming Dynasty Great Wall of Gaotai, Gansu province. The results showed that the plant root systems of P. gansuensis distributed mainly in the north side of the ruins, extending from south to north. The lateral roots distributed around the plant taproot. The plant root systems of P. gansuensis distributed mainly at a the depth of 35~85 cm. The diameter of the taproot is about 12cm. The maximum measurable depth that the 400MHz antenna could reach was 200 cm below the surface. However, the detection precision of a 900MHz antenna is much greater than that of a 400 MHz antenna. If both were used, more information could be obtained on the growth status and the range of distribution of plant root systems. For the first time, threedimensional images of the root system were provided by the portable ground penetrating radar technology. Furthermore, the depth and location of the underground root system can be confirmed in a nondestructive way. This technology provides important scientific information for the protection and consolidation of the Great Wall site.