Environmental Sciences Division, National Exposure Research Laboratory, U.S. Environmental Protection Agency, 109 T. W. Alexander Drive, Research Triangle Park, North Carolina 27711, USA.
Ecol Appl. 2012 Jan;22(1):8-19. doi: 10.1890/10-1573.1.
Meeting future biofuel targets set by the 2007 Energy Independence and Security Act (EISA) will require a substantial increase in production of corn. The Midwest, which has the highest overall crop production capacity, is likely to bear the brunt of the biofuel-driven changes. In this paper, we set forth a method for developing a possible future landscape and evaluate changes in practices and production between base year (BY) 2001 and biofuel target (BT) 2020. In our BT 2020 Midwest landscape, a total of 25 million acres (1 acre = 0.40 ha) of farmland was converted from rotational cropping to continuous corn. Several states across the Midwest had watersheds where continuous corn planting increased by more than 50%. The output from the Center for Agriculture and Rural Development (CARD) econometric model predicted that corn grain production would double. In our study we were able to get within 2% of this expected corn production. The greatest increases in corn production were in the Corn Belt as a result of conversion to continuous corn planting. In addition to changes to cropping practices as a result of biofuel initiatives we also found that urban growth would result in a loss of over 7 million acres of productive farmland by 2020. We demonstrate a method which successfully combines economic model output with gridded land cover data to create a spatially explicit detailed classification of the landscape across the Midwest. Understanding where changes are likely to take place on the landscape will enable the evaluation of trade-offs between economic benefits and ecosystem services allowing proactive conservation and sustainable production for human well-being into the future.
要实现 2007 年《能源独立与安全法案》(EISA)设定的未来生物燃料目标,就需要大幅提高玉米产量。拥有最高整体作物生产能力的中西部地区可能首当其冲地受到生物燃料驱动的变化的影响。在本文中,我们提出了一种制定未来可能景观的方法,并评估了从基准年(2001 年)到生物燃料目标(2020 年)之间的做法和生产变化。在我们的 2020 年中西部生物燃料景观中,共有 2500 万英亩(1 英亩=0.40 公顷)的农田从轮作改为连续种植玉米。中西部的几个州的流域,连续种植玉米的面积增加了 50%以上。农业与农村发展中心(CARD)的计量经济学模型的输出预测,玉米谷物产量将翻一番。在我们的研究中,我们能够使玉米产量达到预期的 98%。由于改为连续种植玉米,玉米产量的最大增长出现在玉米带。除了生物燃料计划导致的种植方式变化外,我们还发现,到 2020 年,城市增长将导致超过 700 万英亩的生产性农田流失。我们展示了一种成功地将经济模型输出与网格化土地覆盖数据相结合的方法,从而在中西部地区创建了一个具有空间细节的景观详细分类。了解景观上可能发生的变化将使人们能够评估经济效益和生态系统服务之间的权衡,从而为未来的主动保护和可持续生产以造福人类。