Characterizing landscape and soil erosion dynamics under pipeline interventions in Southwest China

This study compared the pre- and post-landscape properties and soil erosion dynamics in the 5-kilometer long buffer zone of a gas pipeline located in Chongqing, Southwest China, by landscape metrics analysis and compilation of remote sensing data. The pipeline construction was implemented from 2006-2010. We used FRAGSTATS software to calculate landscape metrics and characterize landscape structure of the buffer zone based on information extracted from remote sensing data collected in 2006 and 2010. The land use transition matrix showed that the pre- and post-pipeline landscapes shared the same integral structure with agricultural land as the primary type, accounting for about 70% of the total area. Moreover, the landscape dynamics of the buffer zone was characterized by significant conversion of grasslands and bare land into agricultural land, at 68.22% and 71.06%, respectively. The landscape became less fragmented and heterogeneous and patch shapes became simpler and more regular, with landscape diversity indices relatively unchanged. Moreover, land area subjected to very slight erosion decreased by 27.16 km(2), while strongly, severely and intensely eroded soil types increased. The total amount of soil eroded annually increased from 284.56 x 10(4) tonnes (t) to 305.51 x 10(4) t. Overall, we can conclude that there were no significant impacts of pipeline construction on the landscape dynamics of the 5 km buffer zone, but negative influences on soil erosion did exist. (C) 2011 Published by Elsevier B. V. Selection and/or peer-review under responsibility of School of Environment, Beijing Normal University.