Arizona State University, Department of Civil, Environmental and Sustainable Engineering, 660 S. College Avenue, Tempe, AZ 85281, United States.
Waste Manag. 2016 Oct;56:593-9. doi: 10.1016/j.wasman.2016.07.022. Epub 2016 Jul 27.
The United States generated approximately 730kg of waste per capita in 2013, which is the highest amount of waste among OECD countries. The waste has adverse effects to human health and the environment. One of the most serious adverse effects is greenhouse gas emissions, especially methane (CH4), which causes global warming. However, the United States' amount of waste generation is not decreasing, and the recycling rate is only 26%, which is lower than other OECD countries. In order to decrease waste generation and greenhouse gas emissions, identifying the causality of the waste generation and greenhouse gas emissions from waste sector should be made a priority. The research objective is to verify whether the Environmental Kuznets Curve relationship is supported for waste generation and GDP across the U.S. Moreover, it also confirmed that total waste generation and recycling of waste influences carbon dioxide emissions from the waste sector. Based on the results, critical insight and suggestions were offered to policymakers, which is the potential way to lower the solid waste and greenhouse gas emissions from the waste sector. This research used annually based U.S. data from 1990 to 2012, and these data were collected from various data sources. To verify the causal relationship, the Granger causality test was applied. The results showed that there is no causality between GDP and waste generation, but total waste and recycling generate significantly increasing and decreasing greenhouse gas emissions from the waste sector, respectively. This implies that waste generation will not decrease even if GDP increases. And, if waste generation decreases or the recycling rate increases, greenhouse gas emission will decrease. Based on these results, increasing the recycling rate is first suggested. The second suggestion is to break the causal relationship between MSW and greenhouse gas emission from the waste sector. The third is that the U.S. government should benchmark a successful case of waste management. Based on the research, it is expected that waste generation and carbon dioxide emission from the waste sector can be decreased more efficiently.
2013 年，美国人均产生约 730 千克废物，是经合组织国家中产生废物最多的国家。这些废物对人类健康和环境有不利影响。其中最严重的不利影响之一是温室气体排放，尤其是甲烷（CH4），它会导致全球变暖。然而，美国的废物产生量并没有减少，其回收率仅为 26%，低于其他经合组织国家。为了减少废物产生和温室气体排放，应优先确定废物部门产生的废物和温室气体排放的因果关系。本研究的目的是验证美国的废物产生和 GDP 是否存在环境库兹涅茨曲线关系。此外，还证实了总废物产生量和废物回收利用对废物部门二氧化碳排放的影响。根据研究结果，为政策制定者提供了关键的见解和建议，这是降低废物部门固体废物和温室气体排放的潜在途径。本研究使用了 1990 年至 2012 年美国每年的基础数据，这些数据来自各种数据源。为了验证因果关系，应用了格兰杰因果检验。结果表明，GDP 与废物产生之间没有因果关系，但总废物和回收利用分别对废物部门的温室气体排放产生显著的增加和减少影响。这意味着即使 GDP 增加，废物产生也不会减少。而且，如果废物产生减少或回收利用率增加，温室气体排放将会减少。基于这些结果，首先建议提高回收利用率。其次是打破城市固体废物和废物部门温室气体排放之间的因果关系。第三个建议是，美国政府应该以一个成功的废物管理案例为基准。根据这项研究，可以更有效地减少废物产生和废物部门的二氧化碳排放。
