Influence of soil compaction on carbon and nitrogen mineralization of soil organic matter and crop residues
Influence of soil compaction on carbon and nitrogen mineralization of soil organic matter and crop residues
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土壤压实对土壤有机质和农作物残体碳氮矿化的影响
DOI：
10.1007/s003740050034
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发表时间：
2000-03-01
影响因子：
6.5
通讯作者：
Hofman, G
中科院分区：
文献类型：
--
作者：
De Neve, S;Hofman, G
研究了壤土砂土壤压实对土壤有机质和作物残茬C、N矿化和硝化作用的影响。在6种容重范围为1.2 - 1.6 Mg m（-3）和75%田间容量的条件下，对未改良土壤和韭菜残渣改良土壤样品进行培养。在未改良的土壤中，研究范围内的容重对微生物活性的任何测量都没有显著影响。在最高容重下，硝化速率的微小（但不显著）下降是压实对微生物活性可能产生影响的唯一证据。在改良后的土壤中，各容重培养结束时的矿化N量相等，但随着压实度的增加，一级N矿化率有增加的趋势，但增加幅度不显著。改良土壤的硝化作用受压实影响较大，在1.5和1.6 Mg m（-3）容重处理下，培养3周后NO3——N含量显著低于未压实处理（分别约为总添加氮的8%和16%）。与其他处理相比，当容重为1.6 Mg m（-3）时，碳矿化率明显降低。压实土壤中碳矿化程度的降低会导致有机质积累的增加。由于N矿化不受压实作用的影响（在这里使用的范围内），积累的有机质比未压实的土壤具有更高的C:N比率，因此质量较低。一般来说，在这种土壤中增加土壤压实，从容重为1.5 Mg m（-3）开始，将影响一些微生物驱动的过程。
We studied the influence of soil compaction in a loamy sand soil on C and N mineralization and nitrification of soil organic matter and added crop residues. Samples of unamended soil, and soil amended with leek residues, at six bulk densities ranging from 1.2 to 1.6 Mg m(-3) and 75% field capacity, were incubated. In the unamended soil, bulk density within the range studied did not influence any measure of microbial activity significantly. A small (but insignificant) decrease in nitrification rate at the highest bulk density was the only evidence for possible effects of compaction on microbial activity. In the amended soil the amounts of mineralized N at the end of the incubation were equal at all bulk densities, but first-order N mineralization rates tended to increase with increasing compaction, although the increase was not significant. Nitrification in the amended soils was more affected by compaction, and NO3--N contents after 3 weeks of incubation at bulk densities of 1.5 and 1.6 Mg m(-3) were significantly lower (by about 8% and 16% of total added N, respectively), than those of the less compacted treatments. The C mineralization rate was strongly depressed at a bulk density of 1.6 Mg m(-3), compared with the other treatments. The depression of C mineralization in compacted soils can lead to higher organic matter accumulation. Since N mineralization was not affected by compaction (within the range used here) the accumulated organic matter would have had higher C:N ratios than in the uncompacted soils, and hence would have been of a lower quality. In general, increasing soil compaction in this soil, starting at a bulk density of 1.5 Mg m(-3), will affect some microbially driven processes.