Department of City and Regional Planning, University of North Carolina, CB #3140, New East Building, Chapel Hill, North Carolina 27599-3140, USA.
Ecol Appl. 2009 Dec;19(8):2078-92. doi: 10.1890/08-1803.1.
In the United States, stream restoration is an increasing part of environmental and land management programs, particularly under the auspices of compensatory mitigation regulations. Markets and regulations surrounding stream mitigation are beginning to mirror those of the well-established wetland mitigation industry. Recent studies have shown that wetland mitigation programs commonly shift wetlands across space from urban to rural areas, thereby changing the functional characteristics and benefits of wetlands in the landscape. However, it is not yet known if stream mitigation mirrors this behavior, and if so, what effects this may have on landscape-scale ecological and hydrological processes. This project addresses three primary research questions. (1) What are the spatial relationships between stream and wetland impact and compensation sites as a result of regulations requiring stream and wetland mitigation in the State of North Carolina? (2) How do stream impacts come about due to the actions of different types of developers, and how do the characteristics of impacts sites compare with compensation sites? (3) To what extent does stream compensation relocate high-quality streams within the river network, and how does this affect localized (intrawatershed) loss or gain of aquatic resources? Using geospatial data collected from the North Carolina Division of Water Quality and the Army Corps of Engineers' Wilmington District, we analyzed the behavior of the North Carolina Ecosystem Enhancement Program in providing stream and wetland mitigation for the State of North Carolina. Our results suggest that this program provides mitigation (1) in different ways for different types of permittees; (2) at great distances (both Euclidean and within the stream network) from original impacts; (3) in significantly different places than impacts within watersheds; and (4) in many cases, in different watersheds from original impacts. Our analysis also reveals problems with regulator data collection, storage, and quality control. These results have significant implications given new federal requirements for ecological consistency within mitigation programs. Our results also indicate some of the landscape-scale implications of using market-based approaches to ecological restoration in general.
在美国，溪流恢复是环境和土地管理计划中越来越重要的一部分，特别是在补偿缓解法规的主持下。溪流缓解的市场和法规开始反映湿地缓解行业的良好发展。最近的研究表明，湿地缓解计划通常会将湿地从城市转移到农村地区，从而改变景观中湿地的功能特征和效益。然而，目前还不清楚溪流缓解是否反映了这种行为，如果是这样，这可能对景观尺度的生态和水文过程产生什么影响。本项目主要研究了三个问题。(1) 由于北卡罗来纳州要求溪流和湿地缓解的法规，溪流和湿地影响和补偿地点之间的空间关系是什么？(2) 不同类型的开发商的行为如何导致溪流受到影响，以及影响地点的特征与补偿地点有何不同？(3) 溪流补偿在多大程度上重新安置了河流网络中的高质量溪流，这如何影响局部（流域内）水生资源的损失或获得？本研究利用从北卡罗来纳州水质部和陆军工程兵团威尔明顿区收集的地理空间数据，分析了北卡罗来纳州生态增强计划为该州提供溪流和湿地缓解的行为。我们的研究结果表明，该计划以不同的方式为不同类型的许可证持有者提供缓解：(1) 缓解距离（欧几里得和溪流网络内）与原始影响相差甚远；(2) 补偿地点与流域内的影响地点明显不同；(3) 在许多情况下，补偿地点与原始影响不在同一流域。我们的分析还揭示了监管者数据收集、存储和质量控制方面的问题。鉴于联邦对缓解计划中生态一致性的新要求，这些结果具有重要意义。我们的研究结果还表明，在一般情况下，使用基于市场的方法进行生态恢复会产生一些景观尺度的影响。
