Climate Change and Land-use Histories Active
As part of the USGS Coral Reef Project, we are developing new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
The Problem
In addition to overfishing, physical damage, and coastal development, declining water quality is one of the most serious and sustained threats to coral reefs and is thought to be a primary cause of the global decline in shallow coral reefs. Isolating the effects of water quality stressors is difficult without determining the physical and biological controls on reef health. However, to evaluate recent trends and establish links to environmental and land-use change, there is a need to put these changes into a temporal and spatial context in order to identify thresholds and ranges of variability in the environment.
Our Approach
By measuring both physical changes (such as bioerosion, calcification, and growth rate) and chemical variations, records of climate change and land-use histories can be developed to supplement disperse observational networks and offer an accessible source of hydrologic, environmental, and land-use information in locations where instrumental records are not available. We are conducting innovative research to develop new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
Specifically, we are conducting applied research to strategically address scientific knowledge gaps that impede informed management decisions related to planning and implementing activities in priority coral reef ecosystems and associated watersheds, such as identifying the causes and sources of pollution or estimating load reductions expected from implementation of specific management measures. We apply recently developed nutrient proxies to provide pre-instrumental records of nutrient loading to coral reefs in impacted sites. When these results are coupled to records of reef growth, we can develop a matrix of susceptibility in the context of nutrient loading and changes to carbonate chemistry. We aim to introduce coral-derived time-series information into monitoring and future management decisions to reduce and prevent land-based sources of pollution, including forecasting future impacts and response to load reductions expected from implementation of specific management tactics.
Caption for large image at top of page: Photograph of Asan-1 core (1.17 m in length) taken for image analysis using a Geotek Multi-Sensor Logger (MSL) system. Age dates were assigned based on year of collection, tissue layer, and band counting using annual density growth patterns captured in CT imagery. Image from Prouty et al., 2014
Please also see the associated efforts on the Coral Reef Ecosystem Studies (CREST) Project website:
Learn more about our related studies.
Below are data releases associated with this project.
Below are publications associated with this project.
Reconstructing surface ocean circulation with 129I time series records from corals
Ocean circulation and biogeochemistry moderate interannual and decadal surface water pH changes in the Sargasso Sea
Historic impact of watershed change and sedimentation to reefs along west-central Guam
Environmental assessment of metal exposure to corals living in Castle Harbour, Bermuda
Determination of low-level mercury in coralline aragonite by calcination-isotope dilution-inductively coupled plasma-mass spectrometry and its application to Diploria specimens from Castle Harbour, Bermuda
Coral Ba/Ca records of sediment input to the fringing reef of the southshore of Moloka'i, Hawai'i over the last several decades
Coral proxy record of decadal-scale reduction in base flow from Moloka'i, Hawaii
Geochemical signature of land-based activities in Caribbean coral surface samples
- Overview
As part of the USGS Coral Reef Project, we are developing new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
The Problem
In addition to overfishing, physical damage, and coastal development, declining water quality is one of the most serious and sustained threats to coral reefs and is thought to be a primary cause of the global decline in shallow coral reefs. Isolating the effects of water quality stressors is difficult without determining the physical and biological controls on reef health. However, to evaluate recent trends and establish links to environmental and land-use change, there is a need to put these changes into a temporal and spatial context in order to identify thresholds and ranges of variability in the environment.
Our Approach
By measuring both physical changes (such as bioerosion, calcification, and growth rate) and chemical variations, records of climate change and land-use histories can be developed to supplement disperse observational networks and offer an accessible source of hydrologic, environmental, and land-use information in locations where instrumental records are not available. We are conducting innovative research to develop new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
Specifically, we are conducting applied research to strategically address scientific knowledge gaps that impede informed management decisions related to planning and implementing activities in priority coral reef ecosystems and associated watersheds, such as identifying the causes and sources of pollution or estimating load reductions expected from implementation of specific management measures. We apply recently developed nutrient proxies to provide pre-instrumental records of nutrient loading to coral reefs in impacted sites. When these results are coupled to records of reef growth, we can develop a matrix of susceptibility in the context of nutrient loading and changes to carbonate chemistry. We aim to introduce coral-derived time-series information into monitoring and future management decisions to reduce and prevent land-based sources of pollution, including forecasting future impacts and response to load reductions expected from implementation of specific management tactics.
Caption for large image at top of page: Photograph of Asan-1 core (1.17 m in length) taken for image analysis using a Geotek Multi-Sensor Logger (MSL) system. Age dates were assigned based on year of collection, tissue layer, and band counting using annual density growth patterns captured in CT imagery. Image from Prouty et al., 2014
Please also see the associated efforts on the Coral Reef Ecosystem Studies (CREST) Project website:
- Science
Learn more about our related studies.
- Data
Below are data releases associated with this project.
- Publications
Below are publications associated with this project.
Filter Total Items: 20Reconstructing surface ocean circulation with 129I time series records from corals
The long-lived radionuclide 129I (half-life: 15.7 × 106 yr) is well-known as a useful environmental tracer. At present, the global 129I in surface water is about 1–2 orders of magnitude higher than pre-1960 levels. Since the 1990s, anthropogenic 129I produced from industrial nuclear fuels reprocessing plants has been the primary source of 129I in marine surface waters of the Atlantic and around thAuthorsChing-Chih Chang, George S. Burr, A. J. Timothy Jull, Joellen L. Russell, Dana Biddulph, Lara White, Nancy G. Prouty, Yue-Gau Chen, Chuan-Chou Shen, Weijian Zhou, Doan Dinh LamOcean circulation and biogeochemistry moderate interannual and decadal surface water pH changes in the Sargasso Sea
The oceans absorb anthropogenic CO2 from the atmosphere, lowering surface ocean pH, a concern for calcifying marine organisms. The impact of ocean acidification is challenging to predict as each species appears to respond differently and because our knowledge of natural changes to ocean pH is limited in both time and space. Here we reconstruct 222 years of biennial seawater pH variability in the SAuthorsNathalie F. Goodkin, Bo-Shian Wang, Chen-Feng You, Konrad Hughen, Nancy G. Prouty, Nicholas Bates, Scott DoneyHistoric impact of watershed change and sedimentation to reefs along west-central Guam
Using coral growth parameters (extension, density, calcification rates, and luminescence) and geochemical measurements (barium to calcium rations; Ba/Ca) from coral cores collected in west-central Guam, we provide a historic perspective on sediment input to coral reefs adjacent to the Piti-Asan watershed. The months of August through December are dominated by increased coral Ba/Ca values, correspoAuthorsNancy G. Prouty, Curt D. Storlazzi, Amanda L. McCutcheon, John W. JensonEnvironmental assessment of metal exposure to corals living in Castle Harbour, Bermuda
Environmental contamination in Castle Harbour, Bermuda, has been linked to the dissolution and leaching of contaminants from the adjacent marine landfill. This study expands the evidence for environmental impact of leachate from the landfill by quantitatively demonstrating elevated metal uptake over the last 30 years in corals growing in Castle Harbour. Coral Pb/Ca, Zn/Ca and Mn/Ca ratios and totaAuthorsN.G. Prouty, N.F. Goodkin, R. Jones, C.H. Lamborg, C. D. Storlazzi, K.A. HughenDetermination of low-level mercury in coralline aragonite by calcination-isotope dilution-inductively coupled plasma-mass spectrometry and its application to Diploria specimens from Castle Harbour, Bermuda
We have developed a technique that combines a high temperature quartz furnace with inductively coupled plasma-mass spectrometry for the determination of Hg stored in the annual CaCO3 bands found in coral skeletons. Substantial matrix effects, presumably due to the discontinuous introduction of CO2 to the gas stream, were corrected for by simultaneously supplying a stream of argon containing highlyAuthorsCarl H. Lamborg, Gretchen J. Swarr, Konrad A. Hughen, Ross J. Jones, Scott Birdwhistell, Kathryn Furby, Sujata A. Murty, Nancy G. Prouty, Chun-Mao TsengCoral Ba/Ca records of sediment input to the fringing reef of the southshore of Moloka'i, Hawai'i over the last several decades
The fringing reef of southern Moloka’i is perceived to be in decline because of land-based pollution. In the absence of historical records of sediment pollution, ratios of coral Ba/Ca were used to test the hypothesis that sedimentation has increased over time. Baseline Ba/Ca ratios co-vary with the abundance of red, terrigenous sediment visible in recent imagery. The highest values at One Ali’i arAuthorsN.G. Prouty, M.E. Field, J. D. Stock, S.D. Jupiter, M. McCullochCoral proxy record of decadal-scale reduction in base flow from Moloka'i, Hawaii
Groundwater is a major resource in Hawaii and is the principal source of water for municipal, agricultural, and industrial use. With a growing population, a long-term downward trend in rainfall, and the need for proper groundwater management, a better understanding of the hydroclimatological system is essential. Proxy records from corals can supplement long-term observational networks, offering anAuthorsNancy G. Prouty, Stacy D. Jupiter, Michael E. Field, Malcolm T. McCullochGeochemical signature of land-based activities in Caribbean coral surface samples
Anthropogenic threats, such as increased sedimentation, agrochemical run-off, coastal development, tourism, and overfishing, are of great concern to the Mesoamerican Caribbean Reef System (MACR). Trace metals in corals can be used to quantify and monitor the impact of these land-based activities. Surface coral samples from the MACR were investigated for trace metal signatures resulting from relatiAuthorsN.G. Prouty, K.A. Hughen, J. Carilli