Solaimani Karim, Mortazavi S Mostafa
Department of Watershed Management, University of Mazandaran, P.O. Box 416, Babolsar, Iran.
Pak J Biol Sci. 2008 Jan 15;11(2):265-9. doi: 10.3923/pjbs.2008.265.269.
Land subsidence is a phenomenon that involves the lowering or settling of the earth's surface due to various factors. The land subsidence due to groundwater withdrawal over the world has been seen in many areas. A decrease in ground water level would cause an increase in effective stresses at clay layers which results consolidation of lower layers. Since about 1980, it has been proven that Kerman Province subsidence in Iran is due to extensive ground water withdrawal. Overdraft of groundwater, an increasing of about 6 times since 1969 to 1999, has caused a decline of about 28 m in groundwater level. The rate of subsidence recently is about 5-15 cm. for decline of about one meter in groundwater level. In Rafsanjan area, many problems such as increase in the salinity of groundwater, land subsidence and consequently earth fissures and cracks in buildings are caused by groundwater withdrawal.
地面沉降是一种由于各种因素导致地球表面下沉或沉降的现象。世界各地因抽取地下水导致的地面沉降在许多地区都有出现。地下水位下降会导致粘土层有效应力增加，从而使下层发生固结。自1980年左右以来，已证实伊朗克尔曼省的地面沉降是由于大量抽取地下水所致。地下水超采，自1969年至1999年增加了约6倍，导致地下水位下降了约28米。最近的沉降速率约为每地下水位下降1米5 - 15厘米。在拉夫桑詹地区，抽取地下水导致了许多问题，如地下水中盐分增加、地面沉降，进而导致建筑物出现地裂缝和裂纹。
