Leader J W, Dunne E J, Reddy K R
Wor-Wic Community College, 32000 Campus Drive, Salisbury, MD 21804, USA.
J Environ Qual. 2008 Jan 4;37(1):174-81. doi: 10.2134/jeq2007.0148. Print 2008 Jan-Feb.
The effectiveness of various management practices to reduce phosphorus (P) loss from soil to water can potentially be improved by using by-product materials that have the capacity to sorb phosphorus. This study evaluated the P sorption and desorption potential, and the physicochemical characteristics of various phosphorus sorbing materials. Twelve materials were selected and P sorption potentials ranged between 66 and 990 mg kg(-1). Iron, and calcium drinking water treatment residuals (DWTRs), a magnesium fertilizer by-product, aluminum, and humate materials all removed substantial amounts of P from solution and desorbed little. Humate had the highest maximum P sorption capacity (S(max)). Materials which had a low equilibrium P concentration (EPC(0)) and a high S(max) included aluminum and humate by-products. In a kinetic study, the Fe-DWTR, Ca-DWTR, aluminum, and magnesium by-product materials all removed P (to relatively low levels) from solution within 4 h. Phosphorus fractionation suggests that most materials contained little or no P that was readily available to water. Sand materials contained the greatest P fraction associated with fulvic and humic acids. In general, materials (not Ca-DWTR) and magnesium by-product were composed of sand-sized particles. There were no relationships between particle size distributions and P sorption in materials other than sands. The Ca- and Fe-DWTR, and magnesium by-product also contained plant nutrients and thus, may be desirable as soil amendments after being used to sorb P. Further, using Ca-DWTRs and Fe-DWTRs as soil amendments may also increase soil cation exchange and water holding capacity.
通过使用具有磷吸附能力的副产品材料，有可能提高各种管理措施减少土壤磷（P）流失到水体中的有效性。本研究评估了各种磷吸附材料的磷吸附和解吸潜力以及理化特性。选择了12种材料，磷吸附潜力在66至990 mg kg(-1)之间。铁和钙饮用水处理残余物（DWTRs）、一种镁肥副产品、铝和腐殖质材料都从溶液中去除了大量的磷，且解吸量很少。腐殖质具有最高的最大磷吸附容量（S(max)）。平衡磷浓度（EPC(0)）低且S(max)高的材料包括铝和腐殖质副产品。在一项动力学研究中，铁-DWTR、钙-DWTR、铝和镁副产品材料在4小时内都从溶液中去除了磷（降至相对较低水平）。磷分级表明，大多数材料所含的磷很少或没有易于被水利用的磷。砂质材料中与富里酸和腐殖酸相关的磷组分含量最高。一般来说，材料（不包括钙-DWTR）和镁副产品由砂粒大小的颗粒组成。除了砂质材料外，其他材料的粒径分布与磷吸附之间没有关系。钙和铁-DWTR以及镁副产品还含有植物养分，因此，在用于吸附磷后作为土壤改良剂可能是可取的。此外，使用钙-DWTRs和铁-DWTRs作为土壤改良剂还可能增加土壤阳离子交换量和持水能力。
