美國地質調查所及加州大學戴維斯分校的科學家在沙加緬度──聖華金河三角洲進行一種最新農業形態，土地上生產的不是農作物，而是可以貯存二氧化碳的土壤。
研究團隊已獲得美國加州水資源部門為期三年、約1230萬美元的補助，自2009年春季起在佔地400公頃的三角洲區域針對此項新概念進行實驗。
這項概念計畫稱為「碳素栽植」（carbon farming），試驗地點為三角洲上自然孕育的溼地。這片土地在淘金熱之後，由開發業者「重新開墾」土地改行農業，挖渠排掉沼澤的水，進而讓河流匯流後形成河口灣。
過去150年來，慣行農法將泥炭土暴露在風雨和氧氣之下，碳從土壤中釋放出來，導致三角洲一帶土地的下沈。根據美國地質調查所的研究，在三角洲進行農業種植的島嶼已低於水平面超過20英尺，主要藉由渠道將水排掉，確保土地不受破壞。
碳素栽植計劃的目的是透過溼地復育，培養肥沃的泥炭土，而美國地質學勘查協會和美國加州水資源部門所合作的試驗計劃，已證實了此項概念的可行性。
三角洲形態的碳素栽植特別納入溼地保育，但這項實驗計劃並非毫無風險，誠如美國地質調查所在簡報中所說：「大規模地去操控環境，最後的成果必定是利弊夾雜。」
其中一種可能性是溼地釋放出甲烷和氧化亞氮，這兩種溫室氣體吸熱單位比碳來得高，可能反而抵銷溼地所吸收的碳排放量，美國地質學勘查協會也表示，甲烷的測量在試驗階段變數仍相當大。
Scientists at the U.S. Geological Survey and the University of California, Davis, are exploring a new style of farming in the Sacramento-San Joaquin River Delta that produces not crops but soils that store carbon dioxide.
The research team has won a three-year, $12.3 million grant from the California Department of Water Resources to test the concept on 400 acres in the Delta beginning next spring.
Called carbon farming, the project involves building wetlands, which is what nature originally grew in the Delta. Following the Gold Rush, developers "reclaimed" the land for agriculture by constructing levees to drain swamplands and contain the rivers that form the estuary.
Over the past 150 years, conventional farming practices have exposed fragile peat soils to wind, rain and oxygen, liberating carbon from the soil and causing subsidence, or sinking, of Delta lands. According to the USGS, most of the islands farmed in the Delta are more than 20 feet below the surface of the water. They are kept dry and intact only because of the levees.
The carbon farming project aims to rebuild the rich peat soils by re-establishing wetlands. A pilot project by the USGS and state Department of Water Resources has already shown that it can work.
The Delta brand of carbon farming specifically involves rebuilding wetlands. The project is not without potential risks. As the USGS briefing paper notes, "Large scale efforts to manage the environment have a decidedly mixed record of success."
One possibility is that the wetlands will emit methane and nitrous oxide, two greenhouse gases more potent than carbon dioxide, potentially canceling the benefit of sequestering the carbon. The USGS said measurements of methane varied widely in the pilot.
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In my healing journey and learning to attain the breath awareness, I become aware of the reality that all the creatures of the world are breathing the same breath. Take action, here and now. From my physical being to the every corner of this out of balance's planet.
