Leggo Peter J, Ledésert Béatrice, Christie Graham
Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3 EQ, UK.
Sci Total Environ. 2006 Jun 15;363(1-3):1-10. doi: 10.1016/j.scitotenv.2005.09.055. Epub 2005 Oct 17.
The present work is an extension of earlier research [Leggo, P. (2000) An investigation of plant growth in an organo-zeolitic substrate and its ecological significance. Plant and Soil, 219: 135-146.] in which zeolitic tuffaceous rock containing clinoptilolite, a commonly occurring natural zeolite mineral, was composted with organic waste to produce a very effective bio-fertilizer thought to be activated by a very large increase in the population of nitrifiers. This material has now been modified by the addition of extra untreated zeolitic tuff (i.e. un-ammoniated clinoptilolite). Comparing plant growth in a series of substrates containing increasing amounts of zeolitic tuff the limit of growth enhancement has been established. Aqueous leachate analysis has demonstrated a correlation between shoot growth and the mobilization of cations in the soil pore water. Measurement of soil water suction pressure has shown that soil moisture is directly related to the amount of the zeolitic tuff amendment. It has also been found that the zeolite component of the soil system supports biofilm formation and this behaviour is thought to account for the additional plant growth in substrates containing extra untreated tuff. Similar trends are found for plants growing in clean and metal polluted soils. It is now clear that organo-zeolitic-soil systems offer an opportunity to re-vegetate land made barren by metal pollution and as a consequence, erosion and dissemination of contaminants are reduced. By harvesting metal tolerant plants it would appear feasible to recover metals and clean the rhizosphere simultaneously.
本研究是早期研究[莱戈，P.（2000年）。有机沸石基质中植物生长及其生态意义的研究。《植物与土壤》，219：135 - 146。]的扩展。在早期研究中，将含有斜发沸石（一种常见的天然沸石矿物）的凝灰质火山岩与有机废物进行堆肥，以生产一种非常有效的生物肥料，据认为这种肥料是通过硝化细菌数量的大幅增加而被激活的。现在，这种材料通过添加额外的未处理凝灰质火山岩（即未氨化的斜发沸石）进行了改良。通过比较一系列含有不同量凝灰质火山岩的基质中植物的生长情况，确定了生长增强的限度。对水浸出液的分析表明，地上部生长与土壤孔隙水中阳离子的活化之间存在相关性。对土壤吸水压力的测量表明，土壤湿度与凝灰质火山岩改良剂的用量直接相关。还发现土壤系统中的沸石成分支持生物膜形成，这种行为被认为是含有额外未处理凝灰质的基质中植物额外生长的原因。在清洁土壤和金属污染土壤中生长的植物也发现了类似的趋势。现在很清楚，有机沸石 - 土壤系统为受金属污染而变得贫瘠的土地重新植被提供了机会，因此减少了污染物的侵蚀和扩散。通过收获耐金属植物，似乎有可能同时回收金属并清洁根际。
