喀斯特石漠化演变轨迹的典型案例研究——以贵州盘县为例

本文以1974年MSS、1999年TM、2007年TM影像为基本数据源,辅以实地踏勘,考虑一个完整的峰丛洼地等,扣除其平坝部分后作为评价单元,获得了贵州省盘县3个时期的石漠化数据并计算了石漠化和无石漠化土地的演变轨迹。相应于1974年、1999年、2007年3个时段,研究区土地退化演变轨迹可分为8种,并可进一步归纳为不变型、逆转减弱型、反复型和加重型4种演变过程类型,从1974年、1999年到2007年未发生过变化的不变型轨迹面积占较高的比例。研究区的喀斯特土地可分为石漠化土地、无石漠化土地、石漠化已恢复土地和潜在可恢复石漠化土地。

Evolution tracks of karst rocky desertification:a typical case study in Panxian County

Remotely sensed data such as MSS for 1974,TM for 1999 and 2007,integrated with the field and lab investigation,were used to evaluate karst rocky desertification（KRD） evolving tracks of 1974,1999 and 2007 in Panxian county,Guizhou province.Every karst peak-cluster-depression was considered as an KRD assessment unit except its flat part.The KRD tracks could be divided into 8 types,such as KRD-KRD-KRD and no desertification-no desertification-no desertification,from 1974,1999 to 2007.Furthermore,these 8 types could include changeless KRD,weakening KRD,repeating degradation and aggravating KRD.The unchanged land which had been no change from 1974,1999 to 2007 accounts for a higher proportion.According to the land degradation tracks,the karst area in Panxian county should divided into KRD land,no desertification land,meliorated KRD land and potential restoration land.