Forest stands can be considered as dynamic carbon pools throughout their developmental stages. Silvicultural thinning and initial planting densities for reforestation not only manipulate the structure or composition of vegetation, but also disturb forest floor and soils, which, in turn, influences the dynamics of carbon pools. Understanding these carbon pools both spatially and temporally can provide useful information for land managers to achieve their management goals. Here, we estimated five major carbon pools in experimental ponderosa pine (Pinus ponderosa) plots that were planted to three levels of spacing and where competing vegetation was either controlled (VC) or not controlled (NVC). The objectives were to determine how an early competing vegetation control influences the long-term carbon dynamics and how stand density affects the maximum carbon (C) sequestration for these plantations. We found that planting density did not affect total ecosystem C at either sampling age 28 or 54. Because of competing vegetation ingrowth, the NVC (85 ± 14 Mg ha⁻¹) accumulated greater C than the VC (61 ± 6 Mg ha⁻¹) at age 28. By age 54, the differences between treatments narrow with the NVC (114 ± 11 Mg ha⁻¹) and the VC (106 ± 11 Mg ha⁻¹) as the pines continue to grow relatively faster in the VC when compared to NVC and C of ingrowth vegetation decreased in NVC, presumably due to shading by the overstory pines. The detritus was not significantly different among treatments in either years, although the mean forest floor and soil C was slightly greater in NVC. While NVC appears to sequester more C early on, the differences from the VC were rather subtle. Clearly, as the stands continue to grow, the C of the larger pines of the VC may overtake the total C of the NVC. We conclude that, to manage forests for carbon, we must pay more attention to promoting growth of overstory trees by controlling competing vegetation early, which will provide more opportunities for foresters to create resilient forests to disturbances and store C longer in a changing climate.

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黄松人工林发育过程中造林对碳库的影响

林分在整个发展阶段都可以视为动态碳库。造林的造林稀疏和初始种植密度不仅操纵了植被的结构或组成，而且还扰乱了林地和土壤，继而影响了碳库的动态。在空间和时间上理解这些碳库可以为土地管理者实现其管理目标提供有用的信息。在这里，我们估计了实验性美国黄松（Pinus muderosa）的五个主要碳库）种植到三个间距的地块，并且竞争性植被处于受控（VC）或非受控（NVC）的地块。目的是确定早期竞争性植被控制如何影响长期碳动态，以及林分密度如何影响这些人工林的最大固碳量。我们发现，在采样年龄28或54时，种植密度均不影响总生态系统C。由于竞争性植被向内生长，NVC（85±14 Mg ha ^-1）积累的C大于VC（61±6 Mg ha ^-1））在28岁时到了54岁。NVC（114±11 Mg ha ^-1）和VC（106±11 Mg ha ^-1），因为与NVC相比，VC中的松树继续相对较快地生长，而NVC中向内生长的植被C减少了，这大概是由于过高的松树遮荫所致。尽管这两个年份的平均林地和土壤碳含量略高，但两种处理方法的碎屑差异均无统计学意义。尽管NVC似乎在早期就隔离了更多的C语言，但与VC的区别却相当微妙。显然，随着林分的不断增长，VC大松树的C可能会超过NVC的总C。我们得出的结论是，要管理森林中的碳，我们必须更加重视通过尽早控制竞争性植被来促进过高的树木生长，这将为林业工作者提供更多机会，使其能够创建抵御干扰的有力森林，并在不断变化的气候中更长时间地储存碳。