Decomposition and the contribution of glomalin-related soil protein (GRSP) in heavy metal sequestration: Field experiment
Decomposition and the contribution of glomalin-related soil protein (GRSP) in heavy metal sequestration: Field experiment
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DOI：
10.1016/j.soilbio.2013.10.010
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发表时间：
2014
影响因子：
9.7
通讯作者：
Zhipeng Wu;Zhipeng Wu;K. Mcgrouther;Jidong Huang;Pengbao Wu;Wei-dong Wu;Hailong Wang;Hailong Wang-Hailo
中科院分区：
文献类型：
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作者：
Zhipeng Wu;Zhipeng Wu;K. Mcgrouther;Jidong Huang;Pengbao Wu;Wei-dong Wu;Hailong Wang;Hailong Wang-Hailo
球囊霉素是丛枝菌根真菌分泌的一种金属吸附糖蛋白。估计土壤中球囊霉素的一种方法是球囊霉素相关土壤蛋白（GRSP）。本研究通过田间原位试验研究了GRSP对Pb、Cd的螯合作用。金属螯合对GRSP后续分解的影响也进行了研究。GRSP使用Bradford方法测定为总球囊霉素相关土壤蛋白（T-GRSP）和易提取球囊霉素相关土壤蛋白（EE-GRSP）。140天后，GRSP结合态Pb占土壤总Pb的0.21-1.78%，GRSP结合态Cd占土壤总Cd的0.38-0.98%。然而，当比较土壤有机质（SOM）的基础上，只有4%的铅或镉结合到GRSP级分的SOM相比，40-54%的铅或镉结合到胡敏素和富里酸的SOM级分。在高浓度Pb和Cd污染的土壤中，T-GRSP（EE-GRSP）在140 d后的分解率分别比对照降低了8.0（6.6）%和7.0（7.5）%。在高铅或镉处理组中，我们发现，金属结合GRSP的分数增加，即使总GRSP含量随时间的推移而下降。在所有Pb水平的土壤中，Pb和GRSP-碳之间的质量比从2.3变化到271.4 mg（100 g）− 1，而在高Cd处理组中，Cd和GRSP-碳之间的质量比（0.36 mg（100 g）−1）高于Cd结合腐殖酸组分的质量比。Ourin situfield研究表明，虽然GRSP确实结合了Pb和Cd，但在我们调查的土壤中，与土壤有机质（如腐殖酸和富里酸）相比，其水平微不足道。
Glomalin is a metal-sorbing glycoprotein excreted by arbuscular mycorrhizal fungi (AMF). One method of estimating glomalin in soils is as glomalin-related soil protein (GRSP). In this study the role of GRSP in sequestering Pb and Cd was investigated in anin situfield experiment. The effect of metal sequestration on the subsequent decomposition of GRSP was also investigated. GRSP was determined using the Bradford method as total glomalin-related soil protein (T-GRSP) and as easily extractable glomalin-related soil protein (EE-GRSP). After 140 days, GRSP bound Pb accounted for 0.21–1.78% of the total Pb, and GRSP bound Cd accounted for 0.38–0.98% of the total Cd content in the soil. However when compared on a soil organic matter (SOM) basis, only 4% of the Pb or Cd was bound to the GRSP fraction of the SOM compared with 40–54% of the Pb or Cd bound to the humin and fulvic acids in the SOM fraction. In soils contaminated with the highest levels of Pb and Cd, the T-GRSP (EE-GRSP) decomposition after 140 days was reduced by 8.0 (6.6)% and 7.0 (7.5)%, respectively, when compared with the controls. In the high Pb or Cd treatment groups we found that the fraction of metal bound to GRSP increased even though the total GRSP content declined over time. The mass ratio between Pb and GRSP-carbon changed from 2.3 to 271.4 mg (100 g)−1in all Pb levels soil, while with the high-Cd treatment group the mass ratio between Cd and GRSP-carbon (0.36 mg (100 g)−1) was higher than the mass ratio seen with Cd-bound humic acid fractions. Ourin situfield study shows that while GRSP does bind Pb and Cd, in the soils we investigated, the levels are insignificant compared to soil organic matter such as humic and fulvic acids.