赤子爱胜蚓(Eisenia foetida)和毛利远盲蚓(Amynthas morrisi)对添加造纸污泥土壤的化学和生物学特征的影响

Abstract

将赤子爱胜蚓（<em>Eisenia foetida</em>）和毛利远盲蚓（<em>Amynthas morrisi</em>）接种于混合15%造纸污泥的旱地土和水稻土中，研究不同蚯蚓对不同混合污泥土壤的化学和生物学性状的作用。主成分分析结果显示蚯蚓对混合污泥土壤化学和生物学性质影响与土壤类型和蚯蚓种间差异密切相关（<em>P</em> < 0.05）。方差分析结果显示：（1）在混合污泥旱地土处理中，与对照相比，<em>E. foetida</em>处理的混合污泥土壤pH和Eh分别显著降低了0.22和13个单位（<em>P</em> < 0.05），有机碳和微生物量碳含量，以及过氧化氢酶、N-乙酰-氨基葡萄糖苷酶、脲酶和酸性磷酸酶活性分别降低了22.8%、43.8%、12.4%、48.4%、44.0%和40.7%（<em>P</em> < 0.05），而荧光素二乙酸酯酶活性增加了57.4%（<em>P</em> < 0.05）；<em>A. morrisi</em>处理的混合污泥土壤碱解氮含量、过氧化氢酶、N-乙酰-氨基葡萄糖苷酶和脲酶活性分别明显下降了16.5%，12.4%、33.9%和45.5%（<em>P</em> < 0.05）。另外，两种蚯蚓相比较，<em>E. foetida</em>活动后混合污泥旱地土壤pH和Eh值、有机碳含量和碳氮比分别比<em>A. morrisi</em>活动后土壤降低0.17和10个单位、24.9%和2.26个单位，而代谢熵和荧光素二乙酸酯酶活性显著增高（<em>P</em> < 0.05）。（2）在混合污泥水稻土处理中，与对照相比，<em>E. foetida</em>处理的混合土壤有机碳含量和碳氮比显著提高20.9%和1.02个单位（<em>P</em> < 0.05），全钾含量和呼吸速率明显降低6.11%和33.8%（<em>P</em> < 0.05）；而与对照相比，<em>A. morrisi</em>处理的混合土壤的速效钾含量和过氧化氢酶活性显著提高13.2%和10.8%（<em>P</em> < 0.05），但β-葡萄糖苷酶和荧光素二乙酸酯酶活性分别下降46.7%和34.4%（<em>P</em> < 0.05）。两种蚯蚓相比较，<em>E. foetida</em>处理后混合污泥水稻土的有机碳含量比<em>A. morrisi</em>处理显著增加了15.7%，碳氮比增加0.84个单位，速效钾、呼吸速率和过氧化氢酶活性减少11.4%、36.5% 和 5.51%（<em>P</em> < 0.05）。综上所述，蚯蚓能显著影响混合造纸污泥土壤的化学和生物学特征。蚯蚓在高有机碳和低粘粒含量旱地土壤中活动，能够加速有机碳的分解和释放，降低与土壤有机质分解和养分转化相关的酶活性和微生物量，但增加微生物总体活性；而蚯蚓在低有机碳和高粘粒含量水稻土壤中活动，则能够有助于土壤有机碳储存，对养分和微生物活性的影响相对较小。与<em>A. morrisi</em>相比较，<em>E. foetida</em>对混合污泥旱地土有机碳的分解和释放、微生物活性的提高，以及混合污泥水稻土有机碳的储存等方面的能力均较强，而对混合污泥水稻土钾素转化能力相对较弱。由于造纸污泥具有高有机碳和低养分含量特征，因此污泥农用仍需考虑按一定比例配施高养分含量有机物料。同时，进一步根据土壤类型和选择适宜的蚯蚓品种进行较长期的小区和大田试验，将能够为污泥农用提供更多科学参考。;Two earthworm species (<em>Eisenia foetida</em> and <em>Amynthas morrisi</em>) were inoculated in dryland and paddy soil mixed with 15% paper mill sludge for 30 days. Effects of earthworm on soil chemical and biological properties were evaluated, which included pH and Eh value, contents of organic carbon and dissolved organic carbon, contents of total nitrogen, phosphorus and potassium and their available contents, the ratio of C and N, contents of microbial biomass carbon, soil respiration rate, metabolic quotient, microbial quotient, and activities of catalase, urease, invertase, acid and alkaline phosphatase, β-glucosidase, N-acetyl-glucosaminidase and fluorescein diacetate (FDA) hydrolysis. PCA results showed that: effects of earthworms on the chemical and biological properties of soil mixed with paper mill sludge depend on soil types and earthworm special species (<em>P</em> < 0.05). ANOVA results showed that: (1) in dry land treatments, compared with the control, 0.22 and 13 units of soil pH and Eh values and 22.8% contents of organic carbon were reduced by <em>E. foetida</em> significantly, respectively (<em>P</em> < 0.05). In the meantime,<em> E. foetida </em>reduced contents of microbial biomass carbon, activities of catalase, N-acetyl-glucosaminidase, urease and acid phosphatase by 43.8%, 12.4%, 48.4%, 44.0% and 40.7%, respectively, but increased FDA hydrolysis by 57.4% as well (<em>P</em> < 0.05). Compared with the control, 16.5% reduction of available N contents and 12.4%, 33.9% and 45.5% reduction of activities of catalase, N-acetyl-glucosaminidase and urease were shown by <em>A. morrisi </em>(<em>P</em> < 0.05). In addition, compared to <em>A. morrisi</em>, reductions of 0.17 and 10 units, 24.9% and 2.26 ratio of soil pH and Eh values, organic carbon content and the ratio of carbon to nitrogen were observed significantly by <em>E. foetida</em>, respectively (<em>P</em> < 0.05). Higher of soil metabolic quotient and FDA hydrolysis were shown in <em>E. foetida</em> than <em>A. morrisi </em>treatments. (2) in paddy soil, compared with the control, 20.9% and 1.02 units increase of soil organic carbon and C:N ratio were shown in <em>E. foetida </em>treatments significantly, but 6.11% and 33.8% decreases of total K contents and soil respiration rate were observed as well(<em>P</em> < 0.05). For <em>A. morrisi </em>treatments, 13.2% and 10.8% increases of soil available K contents and catalase activities was observed significantly (<em>P</em> < 0.05), but 46.7% and 34.4% decreases of β-glucosidase activities and FDA hydrolysis were observed as well. Moreover, in paddy soil treatments, 15.7% and 0.84 units increase of organic carbon contents and C:N ratio were shown in <em>E. foetida</em> than <em>A. morrisi </em>treatments, but 11.4%, 36.5% and 5.51% decrease of total K contents, respiration rate and catalase activities were observed as well (<em>P</em> < 0.05). In summary, earthworm had significant effects on the chemical and biological properties in soil amended with the paper mill sludge. In dry land soil with higher contents of organic matter and lower contents of clay, earthworm accelerated organic matter decomposition, released organic carbon, reduced microbial biomass and the related enzyme activities in organic matter decomposition and nutrient transformation, but increased the potential overall microbial activity. In paddy soil with lower contents of organic matter and higher contents of clay, earthworm contributed to soil organic carbon storage, but had less effect on soil nutrient contents and microbial characteristics. To compare with <em>A. morrisi</em>, <em>E. foetida</em> had stronger abilities on accelerating soil organic matter decomposition, releasing organic carbon and enhancing microbial activities in dry land soil, but increasing organic carbon storage in paddy soil. <em>A. morrisi</em> had stronger ability on potassium cycling than <em>E. foetida</em> in paddy soil. The paper mill sludge was rich in organic matter and poor in nutrient contents in our study. According to proportion, other organic matters rich in nutrient contents should be chose and used together with sludge in the further agricultural application. It is recommended that more studies should be performed in plot and field experiment according to soil types and earthworm species as well.