Mondini C, Sequi P
C.R.A. - Istituto Sperimentale per la Nutrizione delle Piante, sez. di Gorizia, Via Trieste, 23, I-34170 Gorizia, Italy.
Waste Manag. 2008;28(4):678-84. doi: 10.1016/j.wasman.2007.09.026. Epub 2007 Nov 26.
Soil organic matter (SOM) is the largest C stock of the continental biosphere with 1550Pg. The size of C reservoir in the soil and environmental concerns on climate change have recently attracted the attention of scientist and politicians on C sequestration as an effective strategy to tackle greenhouse gas (GHG) emissions. It has been estimated that the potential for C storage in world cropland is relevant (about 0.6-1.2PgCy(-1)). However, there are several constraints of C sequestration that raise concern about its effectiveness as a strategy to offset climate change. C sequestration is finite in quantity and time, reversible, and can be further decreased by socio-economic restrictions. Given these limitations, C sequestration can play only a minor role in the reduction of emissions (2-5% of total GHG emission under the highest emission scenarios). Yet, C sequestration is still attractive for two main reasons: it is likely to be particularly effective in reducing atmospheric CO2 levels in the first 20-30yr of its implementation and presents ancillary benefits for environment and sustainability that make it a real win-win strategy. These beneficial implications are discussed in this paper with emphasis on the need of C sequestration not only to offset climatic changes, but also for the equilibria of the environment and for the sustainability of agriculture and of entire human society.
土壤有机质（SOM）是大陆生物圈中最大的碳库，储量达1550Pg。土壤中碳库的规模以及气候变化引发的环境问题，最近吸引了科学家和政治家对碳固存的关注，将其视为应对温室气体（GHG）排放的有效策略。据估计，世界农田的碳储存潜力可观（约0.6 - 1.2PgC y⁻¹）。然而，碳固存存在一些限制因素，这引发了人们对其作为抵消气候变化策略有效性的担忧。碳固存的数量和时间有限，具有可逆性，并且可能会因社会经济限制而进一步减少。鉴于这些限制，碳固存只能在减排中发挥较小的作用（在最高排放情景下占温室气体总排放量的2 - 5%）。然而，碳固存仍然具有吸引力，主要有两个原因：在实施的最初20 - 30年里，它可能对降低大气中的二氧化碳水平特别有效，并且对环境和可持续性具有附带益处，使其成为真正的双赢策略。本文将讨论这些有益影响，重点强调碳固存不仅对于抵消气候变化的必要性，而且对于环境平衡以及农业和整个人类社会可持续性的必要性。
