US Fish and Wildlife Service, Chesapeake Bay Field Office, Annapolis, Maryland.
Department of Civil and Environmental Engineering, Syracuse University, Syracuse, New York, USA.
Integr Environ Assess Manag. 2015 Jul;11(3):355-69. doi: 10.1002/ieam.1612. Epub 2015 Mar 2.
The North Atlantic Landscape Conservation Cooperative LCC (NA LCC) is a public-private partnership that provides information to support conservation decisions that may be affected by global climate change (GCC) and other threats. The NA LCC region extends from southeast Virginia to the Canadian Maritime Provinces. Within this region, the US National Climate Assessment documented increases in air temperature, total precipitation, frequency of heavy precipitation events, and rising sea level, and predicted more drastic changes. Here, we synthesize literature on the effects of GCC interacting with selected contaminant, nutrient, and environmental processes to adversely affect natural resources within this region. Using a case study approach, we focused on 3 stressors with sufficient NA LCC region-specific information for an informed discussion. We describe GCC interactions with a contaminant (Hg) and 2 complex environmental phenomena-freshwater acidification and eutrophication. We also prepared taxa case studies on GCC- and GCC-contaminant/nutrient/process effects on amphibians and freshwater mussels. Several avian species of high conservation concern have blood Hg concentrations that have been associated with reduced nesting success. Freshwater acidification has adversely affected terrestrial and aquatic ecosystems in the Adirondacks and other areas of the region that are slowly recovering due to decreased emissions of N and sulfur oxides. Eutrophication in many estuaries within the region is projected to increase from greater storm runoff and less denitrification in riparian wetlands. Estuarine hypoxia may be exacerbated by increased stratification. Elevated water temperature favors algal species that produce harmful algal blooms (HABs). In several of the region's estuaries, HABs have been associated with bird die-offs. In the NA LCC region, amphibian populations appear to be declining. Some species may be adversely affected by GCC through higher temperatures and more frequent droughts. GCC may affect freshwater mussel populations via altered stream temperatures and increased sediment loading during heavy storms. Freshwater mussels are sensitive to un-ionized ammonia that more toxic at higher temperatures. We recommend studying the interactive effects of GCC on generation and bioavailability of methylmercury and how GCC-driven shifts in bird species distributions will affect avian exposure to methylmercury. Research is needed on how decreases in acid deposition concurrent with GCC will alter the structure and function of sensitive watersheds and surface waters. Studies are needed to determine how GCC will affect HABs and avian disease, and how more severe and extensive hypoxia will affect fish and shellfish populations. Regarding amphibians, we suggest research on 1) thermal tolerance and moisture requirements of species of concern, 2) effects of multiple stressors (temperature, desiccation, contaminants, nutrients), and 3) approaches to mitigate impacts of increased temperature and seasonal drought. We recommend studies to assess which mussel species and populations are vulnerable and which are resilient to rising stream temperatures, hydrological shifts, and ionic pollutants, all of which are influenced by GCC.
北大西洋景观保护合作组织(NA LCC)是一个公私合作伙伴关系,提供信息支持可能受全球气候变化(GCC)和其他威胁影响的保护决策。NA LCC 地区从弗吉尼亚州东南部延伸到加拿大沿海省份。在该地区内,美国国家气候评估记录了气温、总降水量、强降水事件频率和海平面上升的增加,并预测了更剧烈的变化。在这里,我们综合了文献,研究了 GCC 与选定的污染物、营养物和环境过程相互作用,对该地区的自然资源产生不利影响。我们采用案例研究方法,重点研究了 3 种胁迫因素,这些因素在该地区有足够的 NA LCC 特定信息,可以进行有根据的讨论。我们描述了 GCC 与污染物(汞)以及 2 种复杂环境现象(淡水酸化和富营养化)的相互作用。我们还就 GCC 和 GCC 污染物/营养物/过程对两栖动物和淡水贻贝的影响准备了分类群案例研究。一些受高度保护关注的鸟类物种的血液汞浓度与筑巢成功率降低有关。淡水酸化已经对阿迪朗达克山脉和该地区其他地区的陆地和水生生态系统造成了不利影响,由于氮和硫氧化物排放量减少,这些地区正在缓慢恢复。由于沿海湿地的径流量增加和反硝化作用减少,该地区许多河口的富营养化预计将会增加。缺氧可能会因分层加剧而恶化。水温升高有利于产生有害藻类水华(HAB)的藻类物种。在该地区的几个河口,HAB 与鸟类死亡有关。在北大西洋景观保护合作组织地区,两栖动物种群似乎正在减少。一些物种可能会受到 GCC 的不利影响,包括更高的温度和更频繁的干旱。GCC 可能会通过改变溪流温度和在强风暴期间增加泥沙负荷来影响淡水贻贝种群。淡水贻贝对非离子氨敏感,而在较高温度下,非离子氨的毒性更大。我们建议研究 GCC 对甲基汞生成和生物利用度的交互影响,以及 GCC 驱动的鸟类物种分布变化将如何影响鸟类对甲基汞的暴露。需要研究随着 GCC 的进行,酸沉降减少将如何改变敏感流域和地表水质的结构和功能。需要研究 GCC 将如何影响赤潮和鸟类疾病,以及更严重和广泛的缺氧将如何影响鱼类和贝类种群。关于两栖动物,我们建议研究 1)受关注物种的耐热性和水分需求,2)多种胁迫因素(温度、干燥、污染物、营养物)的影响,以及 3)缓解温度升高和季节性干旱影响的方法。我们建议进行研究,以评估哪些贻贝物种和种群对上升的溪流温度、水文变化和离子污染物脆弱,所有这些都受到 GCC 的影响。