Ghosh A K, Bhattacharyya P, Pal R
NBSS and LUP (ICAR), Block-DK, Sector-II, Salt Lake City, Kolkata-700091, West Bengal, India.
Environ Int. 2004 Jun;30(4):491-9. doi: 10.1016/j.envint.2003.10.002.
A study was conducted to see the effect of arsenic contamination on soil quality indicators, viz., microbial biomass, soil respiration, fluorescein diacetate and dehydrogenase (DHG) activity in arsenic contaminated soils of West Bengal. All the parameters were significantly and negatively correlated with all the form of arsenic (bioavailable and total) but the microbial metabolic quotient was significantly and positively correlated with all forms of arsenic, indicating arsenic induced stress to the soil microbial community. This may be due to part of the microbial biomass, which is located in the inner parts of the micro-aggregates of soil, which is affected by arsenic accumulates present in soil particles. Linear regression analysis revealed that the bioavailable arsenic exerted greater inhibitory effect on the soil microbial population than the total arsenic content of soils. Water-soluble arsenic showed more inhibitory effect than NaHCO(3) extractable form, in their association with biological properties of the contaminated soils. Water-soluble form of arsenic was much more toxic than insoluble forms. This signified that with increase in bioavailability, the arsenic exerted more inhibitory effect on these parameters. It is thus suggested that the microbial biomass, fluorescein diacetate and dehydrogenase activity alone and expressed on a soil organic matter basis along with the soil respiration parameters can be helpful in assessing the effects of arsenic on the size and activity of microbial biomass in soils.
开展了一项研究，以考察砷污染对土壤质量指标的影响，即西孟加拉邦砷污染土壤中的微生物生物量、土壤呼吸、荧光素二乙酸酯和脱氢酶（DHG）活性。所有参数均与各种形态的砷（生物可利用态和总量）显著负相关，但微生物代谢商与各种形态的砷显著正相关，表明砷对土壤微生物群落产生了胁迫。这可能是由于部分微生物生物量位于土壤微团聚体内部，受到土壤颗粒中积累的砷的影响。线性回归分析表明，生物可利用态砷对土壤微生物种群的抑制作用比土壤总砷含量更大。在与污染土壤生物学性质的关联中，水溶性砷的抑制作用比碳酸氢钠可提取态更强。砷的水溶性形态比不溶性形态毒性大得多。这表明随着生物有效性的增加，砷对这些参数的抑制作用更强。因此，建议仅基于土壤有机质表示的微生物生物量、荧光素二乙酸酯和脱氢酶活性，以及土壤呼吸参数，有助于评估砷对土壤中微生物生物量大小和活性的影响。
