Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils
Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils
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DOI：
10.5194/bg-6-2759-2009
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发表时间：
2009-01-01
期刊：
影响因子：
4.9
通讯作者：
Vasquez, R.
中科院分区：
文献类型：
--
作者：
Aragao, L. E. O. C.;Malhi, Y.;Vasquez, R.
热带森林的净初级生产力是全球碳循环中最重要但量化最少的组成部分之一。大多数相关研究特别集中于地上粗木生产力的量化，对净初级生产力其他要素所涉及的碳通量、总净初级生产力在地上和地下组成部分之间的分配以及这些模式的主要环境驱动因素知之甚少。在这项研究中，我们量化了10个亚马逊森林地上和地下的NPP，以解决两个问题：(1)亚马逊森林如何在其地上和地下组成部分之间分配生产力？(2)土壤和树叶营养状况和土壤质地如何影响亚马逊森林的生产力？使用标准化方法来衡量生产力的主要要素，我们表明，在白色沙地，净初级生产力在9.3+/-1.3 mg C ha(-1)yr(-1)(平均+/-标准误差)之间变化，在非常肥沃的Terra Preta地点，NPP在17.0+/-1.4 mg C ha(-1)yr(-1)之间变化，总平均值为12.8+/-0.9 mg C ha(-1)yr(-1)。被研究森林平均分配给地上部分和地下部分的净初级生产力的平均比例分别为+/-3%和36+/-3%。地上和地下NPP的比例几乎不随NPP总量的变化而变化。凋落物和细根产量均随NPP总量的增加而增加，而茎产量没有总体变化趋势。总NPP随土壤磷素和叶片氮素状况的增加而增加。然而，NPP在地下的分配与土壤肥力无关，而是随着土壤粘粒含量的增加而减少。
The net primary productivity (NPP) of tropical forests is one of the most important and least quantified components of the global carbon cycle. Most relevant studies have focused particularly on the quantification of the above-ground coarse wood productivity, and little is known about the carbon fluxes involved in other elements of the NPP, the partitioning of total NPP between its above- and below-ground components and the main environmental drivers of these patterns. In this study we quantify the above- and below-ground NPP of ten Amazonian forests to address two questions: (1) How do Amazonian forests allocate productivity among its above- and below-ground components? (2) How do soil and leaf nutrient status and soil texture affect the productivity of Amazonian forests? Using a standardized methodology to measure the major elements of productivity, we show that NPP varies between 9.3 +/- 1.3 Mg C ha(-1) yr(-1) (mean +/- standard error), at a white sand plot, and 17.0 +/- 1.4 Mg C ha(-1) yr(-1) at a very fertile Terra Preta site, with an overall average of 12.8 +/- 0.9 Mg C ha(-1) yr(-1). The studied forests allocate on average 64 +/- 3% and 36 +/- 3% of the total NPP to the above- and below-ground components, respectively. The ratio of above-ground and below-ground NPP is almost invariant with total NPP. Litterfall and fine root production both increase with total NPP, while stem production shows no overall trend. Total NPP tends to increase with soil phosphorus and leaf nitrogen status. However, allocation of NPP to below-ground shows no relationship to soil fertility, but appears to decrease with the increase of soil clay content.