Sea‐level rise and drought interactions accelerate forest decline on the Gulf Coast of Florida, USA

Abstract

Sea-level rise threatens low-lying coastal ecosystems globally. In Florida, USA, salinity stress due to increased tidal flooding contributes to the dramatic and well documented decline of species-rich coastal forest areas along the Gulf of Mexico. Here, we present the results of a study of coastal forest stand dynamics in thirteen 400 m 2 plots representing an elevation gradient of 0.58-1.1 m affected by tidal flooding and rising sea levels. We extended previously published data from 1992-2000 to 2005 to quantify the full magnitude of the 1998-2002 La Niñ a-associated drought. Populations of the dominant tree species, Sabal palmetto (cabbage palm), declined more rapidly during 2000-2005 than predicted from linear regressions based on the 1992-2000 data. Dramatic increases in Juniperus virginiana (Southern red cedar) and S. palmetto mortality during 2000-2005 as compared with 1995-2000 are apparently due to the combined effects of a major drought and ongoing sea-level rise. Additionally, coastal forest stands continued to decline in species richness with increased tidal flooding frequency and decreasing elevation. Stable isotope (H, O) analyses demonstrate that J. virginiana accesses fresher water sources more than S. palmetto. Carbon isotopes reveal increasing d 13 C enrichment of S. palmetto and J. virginiana with increased tidal flooding and decreased elevation, demonstrating increasing water stress in both species. Coastal forests with frequent tidal flooding are unable to support species-rich forests or support regeneration of the most salt-tolerant tree species over time. Given that rates of sea-level rise are predicted to increase and periodic droughts are expected to intensify in the future due to global climate change, coastal forest communities are in jeopardy if their inland retreat is restricted.

Climate change impacts on coastal and pelagic environments in the southeastern Bay of Biscay

“…In tidal areas, this elevation determines the duration and frequency at which coastal habitats are submerged, this being one of the factors controlling the productivity of macrophyte communities (Morris et al 2002). The SLR is already causing the retreat of coastal forests (Williams et al 1999, DeSantis et al 2007), the loss of saltmarshes (Denslow & Battaglia 2002), coral reef bleaching (Jokiel & Brown 2004) and the loss of goods and services (Costanza et al 1997, Schröter et al 2005, Michael 2007.…”

Modeling the potential impacts of climate change on the water table level of selected forested wetlands in the southeastern United States

“…Plant distributions may shift due to drought (Desantis et al, 2007;Mulhouse et al, 2005), and trees may become increasingly susceptible to attack by pests and pathogens (Schlesinger et al, 2016). A warmer and longer growing season corresponds to an increased possibility of droughts and occurrence of wildland fires .…”

Technical Solar Photovoltaic Potential of Scaled Parking Lot Canopies: A Case Study of Walmart U.S.A.

“…Greenhouse gas (GHG) emissions must be reduced to prevent dangerous global climate change (Moss, et al 2010;IEA 2012;IPCC, 2013) and its negative externalities on cities such as: i) higher temperatures and heat waves that result in thousands of deaths from hyperthermia Dhainaut, et al, 2003;Poumadere, et al, 2003) in environments already experiencing heat island effects (Lo et al, 1997); ii) power outages and the concomitant economic disruption; iii) rising sea levels which causes the low-lying coastal urban environments to submerge gradually (Frihy 2003;Moorhead and Brinson, 1995) while beaches and other amenities of the shorelines are erased with erosion (Frihy 2003;Moorhead and Brinson, 1995); iv) increased risk of flooding (Nicholls, et al, 1999) and saltwater intrusion, which can damage water supplies for cities (Bobba, 2002;Frihey,, 2003); v) strong storms, which cause more damage to coastal environments and increase the risk of floods (Desantis, 2007;Allen et al, 2010;Dale, et al, 2001;Carnicer, et al, 2011); and vi) increased risks from fire (Amiro, et al, 2001;Dale, et al, 2001;Flannigan et al, 2009). In addition, although cities are not primarily agricultural, climate changes threaten drastic changes in soil composition (Kirschbaum, 1995) and crop failures (D'Amato and Cecchi, 2008;ICES/CIESM, 2010;Adams, et al, 1990;Parry, et al, 2004) that aggravate global hunger including residents of cities (Parry et al, 2004;Schmidhuber and Tubeillo, 2007;Parry et al, 2005).…”