Multiple benefits of greenhouse gas reduction through inclusion of perennials in cropping systems

大气中温室气体(GHG)浓度的增加被认为是目前实现的全球变暖的原因。农业是温室的重要来源，尤其是一氧化二氮。与所有经济部门一样，农业预计将减少排放。多年生作物对牲畜饲料很重要，并将越来越多地用于生物燃料生产。这项研究计划考察了多年生植物在作物轮作中减少温室气体排放和提高土壤健康的多重好处。多年生植物比一年生作物更好地利用氮肥和粪便，这可以减少一氧化二氮的排放。多年生植物还可以降低氮肥作为非温室气体-氮气流失到大气中的量。减少肥料氮的损失增加了盈利能力，避免了土壤的直接温室气体排放以及与制造和运输化肥有关的排放。豆科多年生植物提供自己的氮素营养，不依赖于氮肥的添加，这减少了与土壤、制造和运输的直接排放相关的化肥的温室气体排放，但豆类产生的氮素对一氧化二氮的排放是不确定的。多年生植物比一年生作物有更广泛的生根系统，在土壤中储存更多的碳，从而减少温室气体的排放。从长期来看，多年生覆盖将土壤食物网改变为更多样化的生物，特别是与根部相关的有益真菌(称为丛枝菌根真菌)和营养丰富的土壤生物，但它们对种植系统内3年的短期影响尚不确定。最近已经证明，这些真菌提供一种形式的碳，称为Glomalin，它可以建立土壤有机质，改善土壤结构。该计划旨在发现作物从常年轮作到年轮作的转换是否会释放储存在土壤中的碳和氮作为温室气体。同样，该方案的目标是解决在从多年生种植制度转变为一年生种植制度从而改善土壤健康的过程中，是否保留了格洛马林和土壤食物网的多样性。

Increasing concentrations of greenhouse gases (GHG) in the atmosphere are believed to be the cause of current realized global warming. Agriculture is an important source of greenhouses, particularly nitrous oxide. Like all sectors of the economy, agriculture is expected to reduce its emissions. Perennial crops are important for livestock feed and will increasingly be used for biofuel production. This research program examines the multiple benefits of inclusion of perennials in crop rotations to reduce greenhouse gas emissions and increase soil health. Perennials utilize nitrogen fertilizers and manures better than annual crops, which could reduce nitrous oxide emissions. Perennials may also lower the amount of fertilizer nitrogen lost to the atmosphere as the non-greenhouse gas, nitrogen gas. Lowering the loss of fertilizer nitrogen increases profitability and avoids direct greenhouse gas emissions from soil and emissions related to manufacturing and transporation of fertilizer. Legume perennials supply their own nitrogen nutrition and are not dependent upon nitrogen fertilizer addition, this reduces greenhouse gas emissions from fertilizers associated with direct emissions from soil, manufacturing and transportation, however emissions of nitrous oxide from legume produced nitrogen is uncertain. Perennials have more extensive rooting systems than annual crops, storing more carbon in soil thus lowering emissions of greenhouse gases. In the long term, perennial cover alters soil food webs to more diverse organisms, particularly beneficial fungi associated with the roots (called arbuscular mycorrhizal fungi) and higher trophic soil organisms, their effect on shorter terms of 3 years within cropping systems is uncertain. Recently it has been demonstrated that these fungi provide a form of carbon, call glomalin, that builds soil organic matter and improves soil structure. This program aims to discover if conversion from the perennial to annual phase in crop rotations, releases carbon and nitrogen stored in soil as greenhouse gases. Similarly, the program aims to resolved if glomalin and diversity of soil food webs is retained upon conversion from perennial to annual phases of cropping systems thus improving soil health.