Grandlic Christopher J, Mendez Monica O, Chorover Jon, Machado Blenda, Maier Raina M
Department of Soil, Water, and Environmental Science, The University of Arizona, 429 Shantz, Tucson, Arizona 85721, USA.
Environ Sci Technol. 2008 Mar 15;42(6):2079-84. doi: 10.1021/es072013j.
Eolian dispersion of mine tailings in arid and semiarid environments is an emerging global issue for which economical remediation alternatives are needed. Phytostabilization, the revegetation of these sites with native plants, is one such alternative. Revegetation often requires the addition of bulky amendments such as compost which greatly increases cost. We report the use of plant growth-promoting bacteria (PGPB) to enhance the revegetation of mine tailings and minimize the need for compost amendment. Twenty promising PGPB isolates were used as seed inoculants in a series of greenhouse studies to examine revegetation of an extremely acidic, high metal contenttailings sample previously shown to require 15% compost amendment for normal plant growth. Several isolates significantly enhanced growth of two native species, quailbush and buffalo grass, in tailings. In this study, PGPB/compost outcomes were plant specific; for quailbush, PGPB were most effective in combination with 10% compost addition while for buffalo grass, PGPB enhanced growth in the complete absence of compost. Results indicate that selected PGPB can improve plant establishment and reduce the need for compost amendment. Further, PGPB activities necessary for aiding plant growth in mine tailings likely include tolerance to acidic pH and metals.
在干旱和半干旱环境中，矿尾矿的风蚀扩散是一个新出现的全球性问题，对此需要经济可行的修复方案。植物稳定技术，即用本地植物对这些场地进行植被恢复，就是这样一种方案。植被恢复通常需要添加大量改良剂，如堆肥，这会大大增加成本。我们报告了利用植物促生细菌（PGPB）来促进矿尾矿的植被恢复，并尽量减少对堆肥改良剂的需求。在一系列温室研究中，选用了20种有前景的PGPB分离株作为种子接种剂，以检验对一种极端酸性、高金属含量的尾矿样本进行植被恢复的情况，该尾矿样本此前显示正常植物生长需要添加15%的堆肥改良剂。几种分离株显著促进了尾矿中两种本地物种——鹌鹑布什和野牛草的生长。在本研究中，PGPB/堆肥的效果因植物种类而异；对于鹌鹑布什，PGPB与添加10%堆肥结合时最有效，而对于野牛草，在完全不添加堆肥的情况下，PGPB也能促进其生长。结果表明，所选的PGPB可以改善植物定植并减少对堆肥改良剂的需求。此外，在矿尾矿中帮助植物生长所需的PGPB活性可能包括对酸性pH值和金属的耐受性。
