Stehouwer Richard, Day Rick L, Macneal Kirsten E
Crop and Soil Science Department, The Pennsylvania State University, University Park, PA 16802-3504, USA.
J Environ Qual. 2006 May 31;35(4):1118-26. doi: 10.2134/jeq2005.0134. Print 2006 Jul-Aug.
Mine reclamation with biosolids increases revegetation success but nutrient addition well in excess of vegetation requirements has the potential to increase leaching of NO3 and other biosolids constituents. A 3-yr water quality monitoring study was conducted on a Pennsylvania mine site reclaimed with biosolids applied at the maximum permitted and standard loading rate of 134 Mg ha(-1). Zero-tension lysimeters were installed at 1-m depth 1 yr before reclamation: three in the biosolids application area, one in a control area (no biosolids). Before reclamation, all water samples had pH in the range 4.7 to 6.2, acidity < 20 mg L(-1), and very low levels of all other measured parameters. Following reclamation, percolate water in the biosolids-treated area had lower pH and greater acidity than the control area. Acidity was greatest during the first winter following biosolids application, decreased during the spring, and showed a similar pattern but with much smaller concentrations the second year. Maximum first- year leachate NO3 concentrations were approximately 300 mg L(-1) and half as large the second year. Estimated inorganic N leaching loss during the first 2 yr after biosolids application was 2327 kg N ha(-1). Aluminum, Mn, Cu, Ni, Pb, and Zn followed similar leaching patterns as did acidity, and their mobilization appeared to be the result of the increased acidity. These results indicate that large applications of low-C/N-ratio biosolids could negatively impact area water quality and that biosolids reclamation practices should be modified to reduce this possibility.
利用生物固体进行矿山复垦可提高植被恢复的成功率，但养分添加量远超植被需求时，有可能增加硝酸盐及其他生物固体成分的淋溶。在宾夕法尼亚州一个用生物固体以134 Mg ha⁻¹的最大允许标准负荷率进行复垦的矿场，开展了一项为期3年的水质监测研究。在复垦前1年，于1米深度安装了零张力渗滤计：在生物固体施用区安装3个，在对照区（未施用生物固体）安装1个。复垦前，所有水样的pH值在4.7至6.2之间，酸度＜20 mg L⁻¹，且所有其他测量参数的水平极低。复垦后，生物固体处理区的渗漏水pH值低于对照区，酸度高于对照区。酸度在施用生物固体后的第一个冬季最大，春季降低，第二年呈现类似模式但浓度小得多。第一年渗滤液中硝酸盐的最大浓度约为300 mg L⁻¹，第二年为其一半。施用生物固体后的前2年，估计无机氮淋溶损失为2327 kg N ha⁻¹。铝、锰、铜、镍、铅和锌的淋溶模式与酸度相似，它们的活化似乎是酸度增加的结果。这些结果表明，大量施用低碳氮比的生物固体可能会对区域水质产生负面影响，应改进生物固体复垦做法以降低这种可能性。
