Sanger D, Blair A, DiDonato G, Washburn T, Jones S, Riekerk G, Wirth E, Stewart J, White D, Vandiver L, Holland A F
South Carolina Sea Grant Consortium, 287 Meeting Street, Charleston, SC 29401, U.S.
NOAA, Center of Excellence in Oceans and Human Health, Center for Human Health Risk, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, SC, 29412, U.S.
Estuaries Coast. 2015 Jan;38(Suppl 1):49-66. doi: 10.1007/s12237-013-9635-y. Epub 2013 May 3.
Upland areas of southeastern U.S. tidal creek watersheds are popular locations for development, and they form part of the estuarine ecosystem characterized by high economic and ecological value. The primary objective of this work was to define the relationships between coastal development, with its concomitant land use changes and associated increases in nonpoint source pollution loading, and the ecological condition of tidal creek ecosystems including related consequences to human populations and coastal communities. Nineteen tidal creek systems, located along the southeastern United States coast from southern North Carolina to southern Georgia, were sampled during summer, 2005 and 2006. Within each system, creeks were divided into two primary segments based upon tidal zoning: intertidal (i.e., shallow, narrow headwater sections) and subtidal (i.e., deeper and wider sections) and then watersheds were delineated for each segment. Relationships between coastal development, concomitant land use changes, nonpoint source pollution loading, the ecological condition of tidal creek ecosystems, and the potential impacts to human populations and coastal communities were evaluated. In particular, relationships were identified between the amount of impervious cover (indicator of coastal development) and a range of exposure and response measures including increased chemical contamination of the sediments, increased pathogens in the water, increased nitrate/nitrite levels, increased salinity range, decreased biological productivity of the macrobenthos, alterations to the food web, increased flooding potential, and increased human risk of exposure to pathogens and harmful chemicals. The integrity of tidal creeks, particularly the headwaters or intertidally-dominated sections, were impaired by increases in nonpoint source pollution associated with sprawling urbanization (i.e., increases in impervious cover). This finding suggests these habitats are valuable early warning sentinels of ensuing ecological impacts and potential public health and flooding risk from sprawling coastal development. Results also validate the use of a conceptual model with impervious cover thresholds for tidal creek systems in the southeast region.
美国东南部潮汐溪流流域的高地地区是开发的热门地点，它们构成了具有高经济和生态价值的河口生态系统的一部分。这项工作的主要目标是确定沿海开发及其伴随的土地利用变化和非点源污染负荷增加与潮汐溪流生态系统的生态状况之间的关系，包括对人类和沿海社区的相关影响。2005年和2006年夏季，对位于美国东南部海岸从北卡罗来纳州南部到佐治亚州南部的19个潮汐溪流系统进行了采样。在每个系统中，根据潮汐分区将溪流分为两个主要部分：潮间带（即浅而窄的源头部分）和潮下带（即更深更宽的部分），然后为每个部分划定流域。评估了沿海开发、伴随的土地利用变化、非点源污染负荷、潮汐溪流生态系统的生态状况以及对人类和沿海社区的潜在影响之间的关系。特别是，确定了不透水覆盖量（沿海开发指标）与一系列暴露和响应措施之间的关系，包括沉积物化学污染增加、水中病原体增加、硝酸盐/亚硝酸盐水平增加、盐度范围增加、大型底栖生物生物生产力下降、食物网改变、洪水风险增加以及人类接触病原体和有害化学物质的风险增加。与无序城市化相关的非点源污染增加（即不透水覆盖增加）损害了潮汐溪流的完整性，特别是源头或潮间带主导的部分。这一发现表明，这些栖息地是随之而来的生态影响以及沿海无序开发带来的潜在公共卫生和洪水风险的宝贵早期预警哨兵。研究结果还验证了在东南部地区对潮汐溪流系统使用具有不透水覆盖阈值的概念模型的合理性。
