Disturbance and recovery of salt marsh arthropod communities in Louisiana and Mississippi following the 2010 BP Deepwater Horizon oil spill in the Gulf of Mexico

Oil spills represent a major environmental threat to coastal wetlands, which provide a variety of critical ecosystem services to humanity. The U.S. Gulf of Mexico is a hub of oil and gas exploration and production with recognized consequences on intertidal habitats, such as the salt marsh. Following the BP Deepwater Horizon oil spill, we sampled the marine invertebrate and the terrestrial arthropod community found in stands of Spartina alterniflora, the most abundant plant in coastal salt marshes, in 2010 as oil was washing ashore and a year later in 2011. In 2010, intertidal crabs and terrestrial arthropods (insects and spiders) were suppressed by oil exposure even in seemingly unaffected stands of plants; however, Littoraria snails appeared unaffected. One year later, crab and arthropods appeared to have largely recovered. Our work is the first attempt that we know of assessing vulnerability of the salt marsh arthropod community to oil exposure, and it suggests that arthropods are both quite vulnerable to oil exposure, and quite resilient, able to recover from exposure within a year if host plants remain healthy. BP's Deepwater Horizon spill in the Gulf Coast presented an opportunity to understand how stress from an oil spill might affect variables that we were measuring in the area. The study was conducted at sites in Louisiana and Mississippi. At each site, a 100m transect was sampled within 5m of the dead zone boundary. Sampling was conducted in August 2010 and August 2011. The number of sites and location of sites differed slightly among years.

溢油事件对海岸湿地构成重大环境威胁，而海岸湿地可为人类提供多种关键生态系统服务。美国墨西哥湾是油气勘探与生产的核心区域，其潮间带生境（如盐沼（salt marsh））所受影响已得到学界广泛证实。在BP深水地平线溢油事件发生后，我们于2010年原油冲上滩涂时，以及次年2011年，对沿海盐沼优势植物互花米草（Spartina alterniflora）群落中的海洋无脊椎动物与陆生节肢动物进行了采样。2010年的调查显示，即便在看似未受影响的互花米草群落中，潮间带蟹与陆生节肢动物（昆虫及蜘蛛）仍因原油暴露受到抑制，但滨螺（Littoraria）似乎未受影响。一年后的2011年，蟹类与节肢动物种群已基本恢复。据我们所知，本研究是首次评估盐沼节肢动物群落对原油暴露的脆弱性的尝试，结果表明节肢动物对原油暴露兼具较高脆弱性与较强恢复力，若宿主植物保持健康，种群可在一年内从暴露影响中恢复。墨西哥湾沿岸的BP深水地平线溢油事件，为我们探究溢油胁迫如何影响该区域的观测变量提供了契机。本研究在路易斯安那州与密西西比州的多个站点开展：每个站点内，在死亡区（dead zone）边界5米范围内布设100米样带进行采样，采样时间分别为2010年8月与2011年8月。两年间的采样站点数量与位置存在小幅差异。