RAPID: Community-level Wetland Stressors, Northern Gulf of Mexico

该项目解决了有关墨西哥湾深水地平线石油泄漏造成的路易斯安那盐沼生物群落变化的科学问题。一个由经验丰富的调查人员组成的小组将在2010年9月和2011年5月对35个以上的盐沼进行采样，增加2010年5月已经从这些地点收集的样本。因此，取样将涵盖沼泽地被石油污染之前、生长季节高峰期和一年之后的时期。 将收集关于主要水生植物（灯心草、互花米草）的生物量、土壤代谢、硫积累变化、稳定同位素特征、固氮率以及寄生和共生无脊椎动物群落的数据。 收集到的数据将被用来检验各种关于慢性和长期压力影响的假设（石油、毒素、分散剂或营养物）对盐沼生态系统的影响，包括对盐沼社区的间接长期后果的预测。这一特大石油泄漏事件提供了一个不寻常的机会，可以了解生态系统的短期和长期压力，但是只有当存在足够大且变化的基线测量时才是如此。 由于对生物体的物理和毒性影响，碳氢化合物溢漏等环境压力因素可对沿海生态系统产生明显和立即的直接影响。 压力源也有间接影响，因为当它们开始降解时，这些化合物通过初级消费者进入食物网，如悬浮物喂养的牡蛎、沉积物喂养的双壳贝类和放牧蜗牛。反过来，这些消费者是包括人类在内的更高营养级生物的食物来源。一个主要的环境压力的影响，因此，级联通过社区的成员较低的营养水平经历的变化，在生长，死亡率和繁殖成功，并作为物种更替发生和代谢途径被改变。 该项目的目标是提供一个基准研究沼泽生态系统的变化，并预测替代状态的补偿管理行动的时间。

This project addresses scientific questions about changes in the biological community of Louisiana salt marshes caused by the Deepwater Horizon oil spill in the Gulf of Mexico. A team of experienced investigators will sample 35+ salt marshes in September 2010 and May 2011, adding to the samples already collected from these sites in May 2010. Thus, the sampling will cover the periods before the marshes are oiled, at the peak of the growing season, and one year later. Data will be collected on the biomass of the dominant aquatic plant (cordgrass, Spartina alterniflora), soil metabolism, changes in sulfur accumulation, stable isotope signatures, nitrogen fixation rate, and the parasitic and symbiotic invertebrate community. The data collected will be used to test various hypotheses about the effects of chronic and long-term stressors (oil, toxins, dispersants, or nutrients) on salt marsh ecosystems, including predictions about indirect long-term consequences to the salt-marsh community.This exceptionally large oil spill event provides an unusual opportunity to learn about the short- and long-term stressors on ecosystems, but only if there are sufficiently large and varied baseline measurements. Environmental stressors such as those arising from hydrocarbon spills, can have visible and immediate direct impacts on coastal ecosystems due to physical and toxic effects on organisms. Stressors also have indirect effects because, as they begin to degrade, the compounds enter food webs via primary consumers such as suspension-feeding oysters, deposit-feeding bivalves, and grazing snails. These consumers, in turn, are food sources for organisms at higher trophic levels, including humans. The effects of a major environmental stressor can, therefore, cascade through the community as members of lower trophic levels undergo changes in growth, mortality, and reproductive success, and as species turnover occurs and metabolic pathways are altered. The project goals are to provide a benchmark study in marsh ecosystem change, and to predict alternative states in time for compensatory management actions.