原文摘要 | Decomposition of plant matter is one way of enriching soil carbon if it takes place securely within the soil; decomposition on the surface, on the other hand, releases carbon into the atmosphere as carbon dioxide. In the humid tropics, for example, organic matter breaks down rapidly, reducing the carbon storage benefits of organic systems. Another option, recently discovered, is to incorporate biochar— burned biomass in a low-oxygen environment. This keeps carbon in soil longer and releases the nutrients slowly over a long period of time. While the burning does release some carbon dioxide, the remaining carbon-rich dark aromatic matter is highly stable in soil. Hence planting fast-growing trees in previously barren or degraded areas, converting them to biochar, and adding them to soil is a quick way of taking carbon from the atmosphere and turning it into an organic slow-release fertilizer that benefits both the plant and the soil fauna. |