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本文综述了影响N在施过肥料的和自然的森林生态系统中的吸持的因素。总的来说,文献认为描述土壤中的异养菌、植物和硝化细菌之间的N竞争概念模型需要做些修改。硝化细菌对N的竞争看来此以前所认识的还要强,特别是在N输入不断提高的情况下(如在被污染的或反复施肥的立地上),认为异养菌是N的最有效的竞争者的假说,在短期且低N输入的情况下是正确的,但对于长期或高N输入来说就未必正确。在缺N的立地上,树木对土壤中的N的明显“挖掘”,意味着在这种条件下N的最有效的竞争者是树木,而不是异养菌。N与土壤有机质的非生物学反应被认为是施肥之后N固定的主要原因,也是在不施肥的立地上有机质分解期间N的有效竞争者。
This paper reviews the factors that influence N uptake in fertilized and natural forest ecosystems. In general, the literature suggests that the conceptual model for N competition describing heterotrophic bacteria in soil, plants and nitrifying bacteria needs to be modified. The competition for nitrobacteria for N seems to be stronger than previously thought, especially when N inputs are constantly increasing (as in polluted or fertilized plots) and heterotrophic bacteria are considered to be the most potent The competitor’s hypothesis is correct for short-term and low-N inputs, but not true for long-term or high-N inputs. In the absence of N, the apparent “digging” of N in the soil by the trees means that the most effective contender for N under such conditions is the tree, not the heterotrophic bacteria. The non-biological reaction of N with soil organic matter is considered to be the main reason for the N fixation after fertilization and is also an effective competitor to N during organic matter decomposition at a fertile site.