USGS report cites the many challenges facing Bay’s recovery; EPA directs pollution cuts for locomotives, ships, ferries; and more…
USGS report cites the many challenges facing Bay's recovery
USGS report cites the many challenges facing Bay's recovery
The Chesapeake Bay is affected by multiple factors, ranging from population growth to climate variability, which will challenge the recovery of the ecosystem.
These findings were published in the report, "Synthesis of USGS Science for the Chesapeake Bay Ecosystem and Implications for Environmental Management," which was part of a comprehensive five-year summary by the U.S. Geological Survey of the major factors affecting the health of the Bay ecosystem and the implications for its management.
Population growth and agricultural lands have contributed to an overabundance of nutrients, sediment and contaminants entering the Bay, as well as the loss of habitats that can retain these pollutants.
Meanwhile, climate change and variability have caused water temperatures in the Bay to exhibit greater extremes during the 20th century than the previous 2,000 years. Sea-level rise related to climate change is contributing to the loss of vital coastal wetlands. The cumulative impact of pollutants, habitat loss, invasive species, climate change and disease has affected the health of fish and bird populations in the Bay and its watershed.
"There are multiple factors affecting the Bay ecosystem which continue to challenge its recovery," said Scott Phillips, coordinator of USGS Chesapeake Bay Studies. "These findings provide implications about the types and locations of actions needed for the recovery of the Bay ecosystem."
Key findings on land use and its relation to water quality and habitats include:
Impervious surfaces increased 41 percent during the 1990s compared to an 8 percent increase in population. This suggests there will be a more rapid delivery of nutrients to streams and an increase in sediment erosion.
Nitrogen and phosphorus concentrations decreased at a majority of the sites in the watershed, but not at a rate that would meet Bay water quality standards by 2010.
Sediment is having an adverse impact on water clarity and underwater grasses in the Bay and stream quality in the watershed, indicating that actions to address sediment will have to focus on the sediment-generating areas in the Piedmont, promote sediment trapping in wetlands and reservoirs, and address shoreline erosion.
The travel time of nutrients and sediment through the watershed ranges from weeks to centuries. This can result in a "lag time" between implementing management actions and improvements in water quality.
Synthetic organic pesticides and their degradation products have been widely detected at low levels in the watershed, including emerging contaminants such as pharmaceuticals and hormones. The results imply there are opportunities to better integrate nutrient, sediment and contaminant reduction measures.
Key findings on the fish and bird populations include:
The health of fish populations in the Bay is affected by multiple factors, including degraded water quality, pathogens and disease. Improving water quality for fisheries may make them less susceptible to disease and pathogens.
Fish (principally male bass) in the Potomac watershed have testicular oocytes-female eggs growing in their testes-a form of intersex. Reproductive abnormalities in fish have been strongly linked with a variety of contaminants that affect their endocrine systems.
Concentrations of DDT and other selected pesticides have declined since the 1970s, while PCB concentrations remain mostly unchanged. The populations of many fish-eating birds have rebounded but other species remain at risk because of legacy and emerging contaminants.
Habitat loss, invasive species and poor water quality have affected the food sources and habitat for seaduck populations, which have declined over the last several decades.
Key findings related to climate change include:
Low dissolved oxygen conditions, which are influenced by climate change and population growth in the watershed, have been much more extensive and severe in the last four decades than at any time in the past 2,500 years.
Sea-level rise from climate change and land subsidence will continue to cause losses and landward migration of tidal wetlands during the coming century.
USGS Circular 1316, "Synthesis of USGS Science for the Chesapeake Bay Ecosystem and Implications for Environmental Management" is available at http://chesapeake.usgs.gov/.
EPA directs pollution cuts for locomotives, ships, ferries
The EPA in March said marine and locomotive engines must meet tougher pollution controls as it seeks dramatic cuts in the amount of smog-causing chemicals and soot coming from trains, cargo ships, tugboats and passenger ferries.
The new regulation would require that new diesel engines used on ships and locomotives produce 90 percent less soot and 80 percent less smog-causing nitrogen oxide beginning within six or seven years.
That should help the Chesapeake as nitrogen oxide emissions are a significant source of nitrogen pollution to the Bay. But because of the slow pace at which locomotives and ships are replaced, it is likely to be 2030 before the impact of the action is fully felt.
"As more and more goods flow through our ports and railways, the EPA is cutting diesel emissions at their source,'' said EPA Administrator Stephen Johnson.
The action brought praise from environmentalists, who had criticized the EPA sharply for issuing smog regulations in March that many health experts view as inadequate.
"This is a good news story," Richard Kassel, director of the clean fuels and vehicles project for the Natural Resources Defense Council, said. "Thousands of asthma attacks and other health emergencies will be avoided as the nation's 40,000 ships and 21,000 diesel locomotives are cleaned up in years to come."
Johnson said the new requirements will be phased in two years earlier than proposed a year ago because of advancements in engine technology. The more protective requirements for locomotive engines go into effect in 2014, and for marine engines in 2015, the EPA said. It also will require that old engines be retrofitted to meet the more stringent emission standards when overhauled.
The rule will cover cargo ships that travel between U.S. ports, vessels on inland waterways, including the Great Lakes, as well as tugboats and passenger ferries in Seattle, WA; and New York City; and other ports. The requirements do not cover oceangoing vessels, including foreign freighters that use U.S. ports, which fall under international standards.
MD Bay fund reduced by half
The Maryland General Assembly appeared ready to slash by half the support for its newly created Bay cleanup fund to help make up for an estimated $333 million drop in revenue for the state.
Lawmakers had proposed to create a $50-million-a-year fund to support Bay cleanup efforts during a special legislative session last fall, but before money was set aside for the first year of the program, the Senate in March moved to reduce funding to $25 million. The House was expected to follow suit.
Cindy Schwartz, executive director of the Maryland chapter of the League of Conservation Voters, said she was "extremely disappointed" after a Senate committee approved the cut.
"Legislators came out aggressively during the special session and said that cleaning up the Chesapeake Bay was important and that even in tough fiscal times, it should be a priority," Schwartz said.
Environmental activists fear that the reduction makes it impossible for Maryland to meet 2010 cleanup goals the state signed onto.
"We've been talking about restoring the Bay for decades, and once again, it's fallen to the bottom of the priority list," said Kim Coble, head of the Chesapeake Bay Foundation's Maryland Office.
Baltimore County expands Growing Home Campaign
Baltimore County's Growing Home Campaign, one of the region's most aggressive efforts to expand urban forests, announced its 2008 program is expanding to include a partnership with Baltimore City.
The Growing Home program is an innovative public-private partnership to increase the tree canopy by offering homeowners comprehensive education about planting trees and a cash incentive-the $10 Growing Home Tree Coupon-to encourage tree planting on private residential land.
Homeowners can receive the $10 Growing Home tree coupon from the Growing Home brochure, which is widely available at county and city facilities, and the Growing Home Campaign website www.baltimorecountymd.gov/go/trees.
Brochures and the website also have information about the value of adding trees to one's property and within existing neighborhoods; guidance about site considerations and tree species selection; and instructions about planting and maintenance.
- Category: Pollution
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