【摘要】 以南京幕府山地区停采59年的废弃采石迹地为样地,选取植被自然恢复过程中具有代表性的木本植物刺槐的年轮盘为实验材料,并以空间代替时间的方法选取不同年代废弃的采石场土壤样本为对照,采用ICP-AES法测定分析刺槐在自然演替的不同时间阶段年轮及土壤样本中重金属Cr与Pb含量的变化,探索废弃采石迹地植被自然恢复过程中土壤重金属的迁移动态规律。结果显示:(1)幕府山废弃采石场植被自然恢复37年后,土壤中Cr、Pb含量均呈逐渐下降的趋势;不同废弃年限土壤中Cr含量表现为谷地>平地>坡地,而Pb含量表现为平地>谷地>坡地。(2)刺槐样木年轮中Cr与Pb的含量分别在0.85～8.05 mg/kg和3～33 mg/kg范围内波动,总体呈逐渐下降的趋势。(3)降水量与平地刺槐年轮中Cr与Pb的含量呈显著正相关;降水量与谷地刺槐年轮中Cr的吸收显著正相关,但与Pb的正相关性不显著;降水量与坡地年轮中Cr与Pb的含量分别呈中度正相关和负相关。研究表明,幕府山废弃采石场土壤中可迁移的重金属Cr和Pb的含量现已经非常少,含量处于安全范围内;地形差异造成重金属Cr和Pb的迁移量存在明显的不同;降雨量对平地刺槐年轮中Cr与Pb的吸收影响最明显。更多还原

【Abstract】 To explore the mobility of heavy metal Cr & Pb in abandoned quarry during natural restoration process,by comparing with Cr & Pb contents in soil of quarries with different abandoned ages,these two elements in soil samples and typical tree-rings of Robinia pseudoacacia under natural restoration in abandoned quarry of Mufu Mountain Area were studied in this research.ICP-AES was applied to analyze the content variation of Cr & Pb during the different periods of restoration stage.It can be clearly indicated that:(1)after 37 years of natural vegetation restoration,Cr & Pb contents in soil decreased gradually;series of Cr & Pb contents in soil of quarries with different abandoned ages are valley>flatland>slope and flatland>valley>slope respectively.(2)Cr & Pb contents in tree rings of R.pseudoacacia vary from 0.85～8.05 mg/kg and 3～33 mg/kg,respectively.But show a decline on the whole.(3)Rainfall shows significant positive correlation with Cr & Pb contents in tree rings of R.pseudoacacia in flatland,the same with Cr content but non-significant positive correlation with Pb in that of valley,moderate positive correlation with Cr content and negative correlation with Pb content in that of slope.Research indicates that removable Cr & Pb contents in soil were very little,their contents were in safe range;differences in topography led to remarkable gap in amount of removable Cr & Pb;precipitation had remarkable effect on Cr & Pb absorption in R.pseudoacacia tree rings grown in flatland.更多还原