中俄原油管道敷设对沿线不同森林类型土壤Cu化学形态的影响

Effects of China-Russia Oil Pipeline Laying on Chemical Speciation of Cu in Soil Under Different Forest Types in Areas Along Pipeline

根据BCR连续提取法,对比分析漠河—大庆输油管道工程沿线不同森林类型作业带和非作业带土壤Cu化学形态,研究管道敷设对大兴安岭森林土壤重金属Cu的影响。结果表明:(1)原油管道敷设之后,大兴安岭不同森林类型作业带土壤全Cu含量均有显著提高(p<0.05),尤其对樟子松林影响最大,0—20cm土层平均全Cu含量增加51.44%,白桦次生林增加幅度最小,为25.58%。(2)管道敷设后对Cu的化学形态也有很大的影响,0—20cm土层兴安落叶松林EX-Cu含量增加最显著,为1.45倍,对樟子松林影响相对较小,增加0.82倍;RED-Cu含量樟子松林变化最大,增幅达80.68%,兴安落叶松林影响相对较小,增加23.59%;OXI-Cu含量樟子松林增幅最大,达1.15倍,兴安落叶松林为0.50倍,白桦林为0.35倍;RESCu平均含量增加排序为兴安落叶松林(34.07%)>樟子松林(18.35%)>白桦林(9.29%)。(3)管道敷设后白桦林、兴安落叶松林、樟子松林作业带土壤RES-Cu占全Cu含量比例分别降低了12.91%,5.43%和21.65%;白桦林和樟子松林作业带土壤RED-Cu所占比例分别增加了25.56%和19.63%,OXI-Cu分别增加了7.83%和42.13%。由此可见,原油管道的敷设对大兴安岭森林土壤Cu含量影响很大,可溶性Cu含量增加可能导致水资源水质的改变,影响生态环境,因此,需采取相应的防治措施,保证地区的生态安全。

Based on BCR sequential extraction method,we compared and analyzed the chemical speciation of Cu in soil of operational region and non-operational region under different forest types along the Mohe-Daqing pipeline,and study the effects of the pipeline laying on Cu in forest soil of great Xing＇an mountains.The results showed that：（1）After the laying of the oil pipeline,the contents of total Cu in operational region of different forest types of great Xing＇an mountains all increased（p〈0.05）,especially for Mongolian pine forest,in which the average content of total Cu in 0—20cm soil layer increased by 51.44%.In white birch secondary forest,the average content of total Cu in 0—20cm soil layer increased by 25.58%,which was lower than those in other forest types.（2）The pipeline also significantly influenced the chemical speciation of Cu in the 0—20cm soil layer.After the laying of the oil pipeline,in the 0—20cm soil layer,the weak acid extractable Cu（EX-Cu）content increased most greatly in Larix gemelinii forest,which rose 1.45 fold,while increased by 82% in Mongolian pine forest.The reducible Cu（RED-Cu）content increased by 80.68% in Mongolian pine forest,while only increased by 23.59%in Larix gemelinii forest.The oxidizable Cu（OXICu）content increased 1.15 fold in Mongolian pine forests,while only increased by 50% and 35%in Larix gemeliniiand white birch forests,respectively.The increases in average content of residual Cu（RES-Cu）in soil of different forest types listed in the following order：Larix gemelinii forest（34.07%）〉Mongolian pine forest（18.35%）〉 white birch secondary forest（9.29%）.（3）After the laying of the oil pipeline,the proportion of RES-Cu in total Cu decreased by 12.91%,5.43% and 21.65%in operational regions of whitebirches,Larix gemelinii and Mongolian pine forests,respectively,while the proportion of RED-Cu increased by 25.56% and 19.63% in white birches and Mongolian pine forests,respectively,and the proportion of OXI-Cu increased by 7.83% and 42.13%,respectively.The results showed that the laying of oil pipeline could significantly influence the content of Cu in forest soil of great Xing＇an mountains.The increases of soluble Cu may lead to water quality changes and affect the ecological environment.Therefore,correspondent measures should be applied for ecological protection of this region.