Department of Earth and Environment, Florida International University, 11200 SW 8th St. Miami, FL 33174, United States; Science Department, Everglades Foundation, 18001 Old Cutler Road, Suite 625, Palmetto Bay, FL 33157, United States.
Science Department, Everglades Foundation, 18001 Old Cutler Road, Suite 625, Palmetto Bay, FL 33157, United States.
J Environ Manage. 2014 Oct 1;143:162-72. doi: 10.1016/j.jenvman.2014.04.031. Epub 2014 Jun 4.
Water quality and economic models were linked to assess the economic and environmental benefits of implementing a phosphorus credit trading program in an agricultural sub-basin of Lake Okeechobee watershed, Florida, United States. The water quality model determined the effects of rainfall, land use type, and agricultural management practices on the amount of total phosphorus (TP) discharged. TP loadings generated at the farm level, reaching the nearby streams, and attenuated to the sub-basin outlet from all sources within the sub-basin, were estimated at 106.4, 91, and 85 mtons yr(-)(1), respectively. Almost 95% of the TP loadings reaching the nearby streams were attributed to agriculture sources, and only 1.2% originated from urban areas, accounting for a combined TP load of 87.9 mtons yr(-)(1). In order to compare a Least-Cost Abatement approach to a Command-and-Control approach, the most cost effective cap of 30% TP reduction was selected, and the individual allocation was set at a TP load target of 1.6 kg ha(-1) yr(-1) (at the nearby stream level). The Least-Cost Abatement approach generated a potential cost savings of 27% ($1.3 million per year), based on an optimal credit price of $179. Dairies (major buyer), ornamentals, row crops, and sod farms were identified as potential credit buyers, whereas citrus, improved pastures (major seller), and urban areas were identified as potential credit sellers. Almost 81% of the TP credits available for trading were exchanged. The methodology presented here can be adapted to deal with different forms of trading sources, contaminants, or other technologies and management practices.
水质和经济模型被联系起来，以评估在美国佛罗里达州奥基乔比湖流域农业子流域实施磷信用交易计划的经济和环境效益。水质模型确定了降雨、土地利用类型和农业管理实践对总磷（TP）排放量的影响。在农场一级产生的 TP 负荷，到达附近的溪流，并从子流域内的所有来源衰减到子流域出口，分别估计为 106.4、91 和 85 公吨 yr(-)(1)。到达附近溪流的 TP 负荷中，近 95%归因于农业来源，只有 1.2%来自城市地区，合计 TP 负荷为 87.9 公吨 yr(-)(1)。为了将最低成本减排方法与命令与控制方法进行比较，选择了最具成本效益的 30%TP 减排上限，并且个人分配设定为 1.6 公斤 TP 负荷目标公顷(-1)yr(-1)（在附近的溪流水平）。基于最优信用价格 179 美元，最低成本减排方法产生了 27%（每年 130 万美元）的潜在成本节约。奶牛场（主要买家）、观赏植物、大田作物和草皮农场被确定为潜在的信用买家，而柑橘、改良牧场（主要卖家）和城市地区被确定为潜在的信用卖家。近 81%的 TP 信用可用于交易。这里提出的方法可以适应不同形式的交易来源、污染物或其他技术和管理实践。
