Blending foundry sands with soil: Effect on dehydrogenase activity
Blending foundry sands with soil: Effect on dehydrogenase activity
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DOI：
10.1016/j.scitotenv.2005.04.032
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发表时间：
2006-03-15
影响因子：
9.8
通讯作者：
Lee, B
中科院分区：
文献类型：
--
作者：
Dungan, RS;Kukier, U;Lee, B
每年，美国铸造厂都会填埋数百万吨不能再用于制造金属铸造模具和芯的沙子。这些材料的一个可能用途是作为人造土壤的成分；然而，潜在的有害金属和树脂粘合剂（用于制造岩心）可能会对土壤微生物群落产生不利影响。在本研究中，测定了用型砂（粘土包覆砂称为“绿砂”）或芯砂在10%，30%和50%（干重量）下改性的土壤的脱氢酶活性（DHA）。绿砂是从铁、铝和黄铜铸造厂获得的；芯砂采用酚醛树脂或糠醇树脂配制。总的来说，这些砂的增加导致DHA的减少，这种情况持续了12周的实验期。含有高浓度Cu、Pb和Zn的黄铜绿砂严重影响了DHA。到第12周，30%和50%治疗组均未检测到DHA。相比之下，铝绿砂处理土壤的DHA在第4周平均比对照高2.1倍（所有混合比例），在第12周平均比对照高1.4倍（仅30%和50%处理）。在砂处理过的土壤中，DHA的测定结果与铝绿砂和铁绿砂处理过的土壤相似。在某些处理中，活性增加可能是土壤微生物利用核心树脂作为碳源的结果。DHA测定是由铸造砂成分引起的环境应力的敏感指标，可能有助于评估哪些铸造砂适合在环境中有益使用。(C) 2005 Elsevier b.v.版权所有
Each year U.S. foundries landfill several million tons of sand that can no longer be used to make metalcasting molds and cores. A possible use for these materials is as an ingredient in manufactured soils; however, potentially harmful metals and resin binders (used to make cores) may adversely impact the soil microbial community. In this study, the dehydrogenase activity (DHA) of soil amended with molding sand (clay-coated sand known as "green sand") or core sands at 10%, 30%, and 50% (dry wt.) was determined. The green sands were obtained from iron, aluminum, and brass foundries; the core sands were made with phenol-formaldehyde or furfuryl alcohol based resins. Overall, incremental additions of these sands resulted in a decrease in the DHA which lasted throughout the 12-week experimental period. A brass green sand, which contained high concentrations of Cu, Pb, and Zn, severely impacted the DHA. By week 12 no DHA was detected in the 30% and 50% treatments. In contrast, the DHA in soil amended with an aluminum green sand was 2.1 times higher (all blending ratios), on average, at week 4 and 1.4 times greater (30% and 50% treatments only) than the controls by week 12. In core sand-amended soil, the DHA results were similar to soils amended with aluminum and iron green sands. Increased activity in some treatments may be a result of the soil microorganisms utilizing the core resins as a carbon source. The DHA assay is a sensitive indicator of environmental stress caused by foundry sand constituents and may be useful to assess which foundry sands are Suitable for beneficial use in the environment. (C) 2005 Elsevier B.V All rights reserved.