XBEACH: A TOOL FOR ASSESSING THE VULNERABILITY OF BARRIER ISLANDS TO THE EFFECTS OF CLIMATE CHANGE

Abstract. Groundwater abstraction from coastal aquifers is vulnerable to climate change and sea level rise because both may potentially impact saltwater intrusion and hence groundwater quality depending on the hydrogeological setting. In the present study the impacts of sea level rise and changes in groundwater recharge are quantified for an island located in the Western Baltic Sea. Agricultural land dominates the western and central parts of the island, which geologically are developed as push moraine hills and a former lagoon (later wetland area) behind barrier islands to the east. The low-lying central area of the island was extensively drained and reclaimed during the second half of the 19th century. Summer cottages along the beach on the former barrier islands dominate the eastern part of the island. The main water abstraction is for holiday cottages during the summer period (June–August). The water is abstracted from 11 wells drilled to a depth of around 20 m in the upper 5–10 m of a confined chalk aquifer. Increasing chloride concentrations have been observed in several abstraction wells and in some cases the WHO drinking water standard has been exceeded. Using the modeling package MODFLOW/MT3D/SEAWAT the historical, present and future freshwater–sea water distribution is simulated. The model is calibrated against hydraulic head observations and validated against geochemical and geophysical data from new investigation wells, including borehole logs, and from an airborne transient electromagnetic survey. The impact of climate changes on saltwater intrusion is found to be sensitive to the boundary conditions of the investigated system. For the flux-controlled aquifer to the west of the drained area only changes in groundwater recharge impacts the freshwater–sea water interface whereas sea level rise do not result in increasing sea water intrusion. However, on the barrier islands to the east of the reclaimed area below which the sea is hydraulically connected to the drainage canal, and the boundary of the flow system therefore controlled, the projected changes in sea level, groundwater recharge and stage of the drainage canal all have significant impacts on saltwater intrusion and hence the chloride concentrations found in the abstraction wells.

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Coastalplain Honeycombhead, Balduina angustifolia

EDIS ◽

10.32473/edis-sg163-2018 ◽

2018 ◽

Vol 2018 (5) ◽

Author(s):

Debbie Miller ◽

Mack Thetford ◽

Chris Verlinde ◽

Gabriel Campbell ◽

Ashlynn Smith

Keyword(s):

Climate Change ◽

Gulf Of Mexico ◽

Coastal Plain ◽

Native Plants ◽

Barrier Islands ◽

Northern Gulf Of Mexico ◽

Fact Sheet ◽

Dune Restoration ◽

Florida Panhandle

Coastalplain honeycombhead is found in beach dunes, coastal grasslands, and scrub throughout Florida and into Alabama and Mississippi. It is a prolific flower and seed producer that attracts numerous pollinators, including the gulf fritillary butterfly. Interestingly, the endemic, solitary, and ground-dwelling coastal plain Hesperapis (Hesperapis oraria), also known as Balduina bee, is completely dependent on the coastalplain honeycombhead for survival, only emerging from the ground a few weeks each year in September to October to collect pollen and nectar (Hunsburger 2013). This bee only occurs on barrier islands and peninsulas in the northern Gulf of Mexico (Hunsburger 2013) and is particularly vulnerable to climate-change-driven sea-levelrise and habitat fragmentation.https://edis.ifas.ufl.edu/sg163 Note: This fact sheet is also available as a chapter in a comprehensive manual titled Dune Restoration and Enhancement for the Florida Panhandle, Please see the manual for more information about other useful and attractive native plants for dunes and for further information about restoration and preservation techniques.

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Averting robo-bees: why free-flying robotic bees are a bad idea

Emerging Topics in Life Sciences ◽

10.1042/etls20190063 ◽

2019 ◽

Vol 3 (6) ◽

pp. 723-729

Author(s):

Roslyn Gleadow ◽

Jim Hanan ◽

Alan Dorin

Keyword(s):

Climate Change ◽

Computer Simulation ◽

Food Security ◽

European Countries ◽

Plant Interactions ◽

Plant Insect Interactions ◽

Native Habitat ◽

Insect Pollinators ◽

Insect Interactions

Food security and the sustainability of native ecosystems depends on plant-insect interactions in countless ways. Recently reported rapid and immense declines in insect numbers due to climate change, the use of pesticides and herbicides, the introduction of agricultural monocultures, and the destruction of insect native habitat, are all potential contributors to this grave situation. Some researchers are working towards a future where natural insect pollinators might be replaced with free-flying robotic bees, an ecologically problematic proposal. We argue instead that creating environments that are friendly to bees and exploring the use of other species for pollination and bio-control, particularly in non-European countries, are more ecologically sound approaches. The computer simulation of insect-plant interactions is a far more measured application of technology that may assist in managing, or averting, ‘Insect Armageddon' from both practical and ethical viewpoints.

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Modelling ecosystem adaptation and dangerous rates of global warming

Emerging Topics in Life Sciences ◽

10.1042/etls20180113 ◽

2019 ◽

Vol 3 (2) ◽

pp. 221-231 ◽

Cited By ~ 4

Author(s):

Rebecca Millington ◽

Peter M. Cox ◽

Jonathan R. Moore ◽

Gabriel Yvon-Durocher

Keyword(s):

Climate Change ◽

Global Warming ◽

Diffusion Rate ◽

Individual Species ◽

Genetic Evolution ◽

Rates Of Change ◽

Rapid Climate Change ◽

Warming Climate ◽

Intraspecies Competition ◽

High Trait

Abstract We are in a period of relatively rapid climate change. This poses challenges for individual species and threatens the ecosystem services that humanity relies upon. Temperature is a key stressor. In a warming climate, individual organisms may be able to shift their thermal optima through phenotypic plasticity. However, such plasticity is unlikely to be sufficient over the coming centuries. Resilience to warming will also depend on how fast the distribution of traits that define a species can adapt through other methods, in particular through redistribution of the abundance of variants within the population and through genetic evolution. In this paper, we use a simple theoretical ‘trait diffusion’ model to explore how the resilience of a given species to climate change depends on the initial trait diversity (biodiversity), the trait diffusion rate (mutation rate), and the lifetime of the organism. We estimate theoretical dangerous rates of continuous global warming that would exceed the ability of a species to adapt through trait diffusion, and therefore lead to a collapse in the overall productivity of the species. As the rate of adaptation through intraspecies competition and genetic evolution decreases with species lifetime, we find critical rates of change that also depend fundamentally on lifetime. Dangerous rates of warming vary from 1°C per lifetime (at low trait diffusion rate) to 8°C per lifetime (at high trait diffusion rate). We conclude that rapid climate change is liable to favour short-lived organisms (e.g. microbes) rather than longer-lived organisms (e.g. trees).

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