United States Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, Sustainable Technology Division, Sustainable Environments Branch, Cincinnati, OH 45268, USA.
J Environ Manage. 2012 Nov 30;111:279-86. doi: 10.1016/j.jenvman.2011.07.005. Epub 2011 Oct 26.
We calculated an Ecological Footprint Analysis (EFA) at a regional scale. EFA captures the human impact on the environmental system by identifying the amount of biologically productive land necessary to support a person's level of consumption and waste generation. EFA is a commonly used metric of sustainability because it is easy to conceptualize and the calculation is relatively straightforward. Utilizing free, readily available data, we calculated an EFA for a region in southern Colorado. Gathering existing data at a regional scale is difficult because data are often collected at national or state levels. The lack of data is further confounded by the fact that data are often collected at intervals greater than one year. Variables that were missing data for certain years were estimated using linear interpolation. Data not available by county were scaled to the region from state or national level data. Thirty-five variables from 1980 to 2005 (26 years) were collected and used to calculate a time-dependent EFA and the resulting trend was visually examined. The available biocapacity in the region did not decrease during the period, but per capita biocapacity decreased due to population growth. Per capita biocapacity was at a period high of nearly 41 ha per person (ha/ca) in 1980 and steadily decreased to a low around 31 ha/ca in 2005. Ecological footprint remained constant over the 26-year period, varying from a low of 5.1 ha/ca in 1997 to a high of 5.5 ha/ca in 1985. A steady ecological footprint combined with a decreasing per capita biocapacity, implies the ecological reserve is decreasing and, thus, the region is moving away from sustainability. Although per capita consumption did not increase substantially during the 26 years, more people are drawing on a fixed quantity of resources. Our methodology is a simplified approach to EFA and does not follow standards that are currently being established. Adhering to the suggested standards would require obtaining data sets that consist entirely of national data. The national level data are replaced with data specific to the geographic area under examination when they are available. Although national data may represent the sub-national region under study, that substitution requires further investigation, especially in large, geographically and culturally varied nations such as the US. Nevertheless, this simplified methodology provides enough detail that stakeholders can identify areas of the system on which to focus attention to improve sustainability of the system.
我们在区域尺度上进行了生态足迹分析 (EFA)。EFA 通过确定支持一个人的消费和废物产生水平所需的生物生产力土地数量，来捕捉人类对环境系统的影响。EFA 是一种常用的可持续性衡量标准，因为它易于理解，并且计算相对简单。我们利用免费的、现成的数据，对科罗拉多州南部的一个地区进行了 EFA 计算。在区域尺度上收集现有数据很困难，因为数据通常是在国家或州一级收集的。由于数据通常是每隔一年以上收集一次，因此数据的缺乏情况更加复杂。对于某些年份缺少数据的变量，我们使用线性插值进行了估计。没有按县划分的数据，是根据州或国家一级的数据进行了区域划分。从 1980 年到 2005 年（26 年）收集了 35 个变量，并用于计算时间相关的 EFA，并且对结果趋势进行了可视化检查。在这段时间内，该地区的可用生物承载力并没有减少，但由于人口增长，人均生物承载力下降了。1980 年，人均生物承载力达到了近 41 公顷/人（ha/ca）的高峰期，随后稳步下降到 2005 年的 31 公顷/人左右。生态足迹在 26 年的时间里保持不变，从 1997 年的 5.1 公顷/人到 1985 年的 5.5 公顷/人不等。稳定的生态足迹加上人均生物承载力的下降，意味着生态储备正在减少，因此该地区正在远离可持续性。尽管在 26 年期间人均消费没有大幅增加，但更多的人正在消耗固定数量的资源。我们的方法是对 EFA 的简化方法，不符合当前正在制定的标准。遵循建议的标准将需要获取完全由国家数据组成的数据集。当可用时，会用特定于所研究地理区域的数据替换国家一级的数据。尽管国家数据可能代表研究中的次国家地区，但这种替代需要进一步调查，尤其是在像美国这样的地域和文化差异较大的大国。尽管如此，这种简化的方法提供了足够的细节，利益相关者可以确定系统中的关注领域，以提高系统的可持续性。
