不同类型有机物料对黑土中Cu、Zn含量及有效性的影响

Effects of Different Kinds of Organic Materials on Contents and Availabilities of Cu and Zn in Black Soil

选取畜禽粪、天然有机物料、半分解有机物料三大类共8种有机物料进行培养实验,采用BCR连续提取法对黑土中Cu、Zn形态进行分级提取,研究了不同类型有机物料对黑土中Cu、Zn这2种元素含量及形态变化特征的影响。研究结果显示:不同类型有机物料对黑土中Cu、Zn总量及各形态含量均有不同程度影响。畜禽粪类有机物料显著增加了黑土中Cu、Zn总量及各形态含量。天然有机物料显著增加了黑土中Zn总量及各形态含量,但对Cu总量影响不明显,对酸可提取态和可还原态Cu含量有显著降低效果,有效降低了黑土中Cu的有效性。半分解有机物料对黑土中Cu、Zn总量影响不显著(草炭对Cu总量有降低效果除外),对各形态Zn含量增加效果不显著,但对可还原态Cu有显著降低效果。不同类型有机物料的施用还导致了黑土中Cu、Zn形态间发生转化.。半分解有机物料有效促使黑土中Cu、Zn从生物有效性高的形态向生物有效性低的形态发生惰性转化。天然有机物料则只促进黑土中Cu发生了惰性转化,使得黑土中Zn发生了活性转化。畜禽粪类有机物料均使得黑土中Cu、Zn发生了活性转化。

3 kinds of organic materials were used for culture experiment, namely livestock manures, natural organic materials and half-decomposed organic materials. And the modified BCR sequential extraction procedure was used to analyze the morphology of Cu and Zn. The study was to investigate the effects of different kinds of organic materials on contents and morphology of Cu and Zn in black soil. The results showed that different kinds of organic materials influenced the total contents of Cu and Zn and the contents of different forms of Cu and Zn. Livestock manures increased the total contents of Cu and Zn and the contents of different forms of Cu and Zn obviously, while natural organic materials only increased the contents of total Zn and different Zn fractions, and had no effects on the total Cu content. At the same time, natural organic materials decreased the weak acid soluble fraction and reducible fraction of Cu, which meant that natural organic materials reduced the effectiveness of Cu in black soil. Half-decomposed organic materials had little effects on the total Cu and Zn contents, except that peat decreased total content of Cu in soil. Half-decomposed organic materials did not obviously increase the content of each fraction of Zn, but showed a significant decreasing consequence on reducible Cu. Different kinds of organic materials also caused morphologic transformations of Cu and Zn. Half-decomposed organic materials promoted Cu and Zn transform from high bioavailability to low bioavailability, which called inert transformation. Natural organic materials only promoted the inert transformation of Cu in black soil, but led to the active transformation of Zn. Livestock manures led to active transformations of both Cu and Zn.