USGS Newsroom

National Assessment Shows Geographic Distributions and Trends of Pesticide Use, 1992-2009

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 16 May 2013 11:35:02 EDT

For the first time, national maps and trend graphs show the distribution of the agricultural use of 459 pesticides for each year during 1992-2009 for the entire conterminous U.S. The maps and supporting national database of county-level use estimates for each pesticide were developed by the U.S. Geological Survey (USGS) for use in national and regional water-quality assessments.

The national use analysis is based on methods developed by USGS to estimate annual county-level pesticide use for agricultural crops grown throughout the conterminous United States. Pesticide-use data compiled from proprietary surveys of farm operations were used in conjunction with annual harvested-crop acreage reported by the U.S. Department of Agriculture (USDA) to calculate use rates for each crop and year. For California, use estimates were obtained directly from annual California Department of Pesticide Regulation Pesticide Use Reports.

"These nationally complete and consistent, county-level use estimates are vital for USGS water-quality models that estimate pesticide concentrations in streams and rivers. In addition, long-term annual data is essential for interpreting water-quality trends," said Wes Stone, an author of the reports.

The new pesticide-use estimates were tested and found to be consistent with national use estimates by the U.S. Environmental Protection Agency and with comparable statewide estimates for selected years and crops by the USDA. The USDA data on pesticide use, which are based on systematic regional surveys for selected years and crops, enabled vital quality assurance of the new estimates.

Gail Thelin, senior author of the report on estimation methods, noted, "When evaluated statistically, USGS estimates agree with estimates from other sources for comparable years, pesticides, and states. That consistency supports the reliability of the comprehensive and long-term assessment of use patterns and trends that is now available through this study."

Complete results of the USGS analysis of pesticide use are provided in three products:

Documentation of Methods: "Estimation of annual agricultural pesticide use for counties of the conterminous United States, 1992–2009": U.S. Geological Survey Scientific Investigations Report 2013-5009

National County-Level Data for 459 Pesticides: "Estimated annual agricultural pesticide use for counties of the conterminous United States, 1992–2009": U.S. Geological Survey Data Series 752

National Maps and Trend Graphs

New Insight on Gas Hydrates in Gulf of Mexico

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 14 May 2013 10:00:00 EDT

Research is Part of a Long-Standing, Interagency Collaboration

Scientists have returned from a 15‑day research expedition in the northern Gulf of Mexico with the best high-resolution seismic data and imagery ever obtained of sediments with high gas hydrate saturations.

The expedition and the data and imagery collected resulted from long-standing cooperation between the U.S. Department of the Interior's U.S. Geological Survey (USGS) and Bureau of Ocean Energy Management (BOEM) and the U.S. Department of Energy (DOE). This collaboration aims to advance scientific understanding of gas hydrates, an important potential future energy resource.

Gas hydrates are ice-like substances formed when certain gases combine with water at specific pressures and temperatures. Deposits of gas hydrates are widespread in marine sediments beneath the ocean floor and in sediments within and beneath permafrost areas, where pressure-temperature conditions keep the gas trapped in the hydrate structure. Methane is the gas most often trapped in these deposits, making gas hydrates a potentially significant source for natural gas around the world.

"This expedition represents a significant milestone," said USGS Energy Resources Program Coordinator Brenda Pierce. "The data and imagery provide insight into the entire petroleum system at each location, including the source of gas, the migration pathways for the gas, the distribution of hydrate-bearing sediments, and the traps that hold the hydrate and free gas in place. The USGS has a globally recognized research effort studying gas hydrates in settings around the world, and this project combines our unique expertise with that of other agencies to advance research on this potential future energy resource."

The recently completed expedition was planned jointly by USGS, DOE, and BOEM, and was executed by USGS. Using low-energy seismic sources, USGS scientists collected details about the nature of the gas hydrate reservoirs and about geologic features of the sediment between the reservoirs and the seafloor. The new data also provide information about how much gas hydrate exists in a much broader area than can be determined from using standard industry seismic data, which is typically designed to image much deeper geologic units.

"Understanding the nature and setting of deepwater gas hydrates is central to the National Methane Hydrates R&D Program, which is led by DOE and managed by Fossil Energy's National Energy Technology Laboratory," said Christopher Smith, DOE’s Acting Assistant Secretary for Fossil Energy. "Over the past 8 years, research carried out under this program has resulted in significant advances in our understanding of methane hydrates, their role in nature, and their potential as a future energy resource. This success is largely due to an unprecedented level of cooperation among federal agencies, industry, national laboratories, and academic institutions."

"The high-resolution nature of the data acquired through this interagency project will uniquely inform the BOEM effort to assess the resource potential of gas hydrates on the U.S. Outer Continental Shelf," said Renee Orr, Chief, Strategic Resources Office, BOEM.

The data were collected at two locations in the Gulf of Mexico where the three federal agencies partnered with an industry consortium to conduct a drilling expedition in 2009. That expedition discovered gas hydrate filling between 50 and 90 percent of the available pore space between sediment grains in sandy layers in the subsurface. These reservoirs are expected to be representative of the 6,700 trillion cubic feet of gas that BOEM estimates is housed in gas hydrates in sand-rich reservoirs in the northern Gulf of Mexico.

The new data are being used to refine estimates of the nature, distribution, and concentration of gas hydrate in the vicinity of the 2009 drill sites. This will help assess how useful specialized seismic data may be to estimating hydrate saturations in deepwater sediments.

In coming years, the three agencies will continue their collaborative investigation of gas hydrates in the northern Gulf of Mexico and other locations across the world.

Learn more about USGS research on gas hydrates and energy at locations around the world.

Stars show the locations of seismic surveys conducted to image previously-identified deepwater gas hydrate deposits in the northern Gulf of Mexico on the research ship Pelican during a cruise in April and May 2013. (Larger image)

This high-resolution image was collected during a seismic cruise to study locations with high concentrations of gas hydrate in the northern Gulf of Mexico in April and May 2013. The data were collected at the Walker Ridge location, where 2009 drilling at the site of the well (shown in red revealed) the distribution of gas hydrates and methane gas in the sediments. The water depth at the well is 6562 feet, and the red and blue colors shown within the image correspond to sediment layers, which mostly dip westward. Sand layers with high concentrations of gas hydrate are marked, but hydrate also occurs elsewhere in this sedimentary section. (Larger image)

USGS Seeks Proposals for Earthquake Research

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 15 Apr 2013 11:30:00 EDT

Applications due June 6, 2013

The U.S. Geological Survey will award up to $4 million in grants for earthquake hazards research in 2014.

"The USGS has a long-standing grants program that has supported fresh and cutting-edge ideas all in an effort to reduce earthquake losses and protect communities," said USGS Senior Science Advisor Bill Leith. "We are looking forward to seeing the new proposals for 2014 and continuing to invest in innovative projects from experts across the nation and the world."

Interested researchers can apply online at GRANTS.GOV under funding opportunity number G13AS00029. Applications are due June 6, 2013.

Each year the USGS awards earthquake hazards research grants to universities, state geological surveys and private institutions. Past projects included cataloging earthquakes in southern California to better prepare emergency responders, the public and the media about earthquakes; providing seismic hazard estimates so communities and critical institutions can engineer their buildings and roads to be structurally sound; and analyzing data on ground shaking to help minimize damage.

A complete list of funded projects and reports can be found on the USGS Earthquake Hazards Program external research support website.

New Software Tool Analyzes Effect of Stream and Lake Levels on Adjacent Lands

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 3 Apr 2013 13:00:00 EDT

PORTLAND, Ore. — The U.S. Geological Survey has developed the "Shoreline Management Tool," a GIS software program designed to test ways of managing land and water resources adjacent to a lake or stream. The new software tool will help water-, land-, and wildlife-resource managers balance competing needs when managing surface-water levels for water quantity, water depth, area of inundation, and area of dry land. These factors relate directly to water supply, water quality, shoreline habitat for plants and animals, and human use of water and land areas.

Assessing the effects of changing surface-water levels historically has been difficult because of the complexity of the analysis. The management tool enables the user to define criteria such as water depth and land-surface slope and aspect to identify areas where conditions meet the needs for certain land or water uses or that provide habitat suitable for specific plants and animals.

The tool comprises an interactive GIS program and spreadsheets that allow users to specify the input data and criteria for analysis, process the data, and create results in the form of maps, data tables, and graphs. The tool is designed for use by natural-resource managers with only limited expertise with GIS.

Although the tool was initially developed to evaluate conditions in the lower Wood River Valley in the upper Klamath Basin, Oregon, it is designed to be transferable to other areas using easily generated or readily available data.

The Shoreline Management Tool was conceived and developed by the USGS with cooperation from the Bureau of Land Management.

The program is documented in the report, "The Shoreline Management Tool—An ArcMap Tool for Analyzing Water Depth, Inundated Area, Volume, and Selected Habitats, with an Example for the Lower Wood River Valley, Oregon," by Daniel T. Snyder, Tana L. Haluska, and Darius Respini-Irwin, is published as U.S. Geological Survey Open-File Report 2012–1247 and is available online.

Water Quality Differences Affect Aquatic Health of Urban Streams in Kansas City and Independence, Missouri

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 22 Mar 2013 11:17:59 EDT

Downstream areas of the Blue River and Little Blue River basins are highly affected by urban development, according to a new U.S. Geological Survey study that compares the aquatic-life status of streams in the Kansas City, Mo. metropolitan area using macroinvertebrate populations as an indicator of stream health.

This study increases our understanding of aquatic life and water quality in urban streams. The differences in aquatic-life status of the Blue River and Little Blue River indicate how stormwater, wastewater discharges, and upstream reservoirs affect urban streams.

Macroinvertebrates, or animals without a backbone that are visible to the unaided eye, were collected in the Blue River basin in Kansas City, Mo., and the Little Blue River and Rock Creek basins in Independence, Mo., as part of two urban water-quality studies to assess the aquatic-life status of urban streams. Aquatic macroinvertebrates, which include insects, worms, mussels, and crayfish, are at the base of the food chain in aquatic environments. They are the main food source for many other animals such as fish and ducks, so scientists commonly use them to study the ability of a stream to support aquatic life.

"None of the samples collected from the Blue River had characteristics considered to be fully able to support aquatic life," said USGS co-author Heather Krempa. "However, about one out of ten spring samples and about four out of ten fall samples from the Little Blue River did have characteristics considered to be fully supporting of aquatic life."

Macroinvertebrate samples were collected from streams and analyzed several ways, including counting the total number and types of macroinvertebrates collected, grouping them based on feeding methods, and calculating the tolerance of the macroinvertebrates to pollution and environmental stress. Samples were scored to provide information about the stream at the sample location and were compared among sites. The aquatic-life status scores for the Little Blue River and its tributaries were higher, indicating more optimal conditions, than for the Blue River and its tributaries.

A Stream Condition Index that combines several different measures of macroinvertebrate populations was used to describe and assign three categories to the stream sites: non-, partially, and fully biologically supporting.

Wastewater-treatment plant discharges during low flows and combined sewer overflows into the Blue River lower aquatic-life scores and likely reduce water quality. Separate stormwater sewer system and reservoir releases to the Little Blue River may raise water quality and aquatic-life scores.

The study, "Assessment of Macroinvertebrate Communities in Adjacent Urban Stream Basins, Kansas City, Missouri, Metropolitan Area, 2007 through 2011," has been released as USGS Scientific Investigations Report 2012-5284 and is available online.

Tool Estimates Streamflow for Pennsylvania Waterways

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 22 Feb 2013 7:51:22 EDT

Editors: The BaSE tool and supporting documentation can be found online.

NEW CUMBERLAND, Pa. -- Water resource managers can now estimate daily baseline streamflows in a matter of minutes for any location along Pennsylvania's waterways. The Baseline Streamflow Estimator, called "BaSE," provides users with estimated daily mean streamflow, minimally altered by human activities, for locations on Pennsylvania streams that don’t have streamgages. Pennsylvania is one of the first states in the nation to have such a tool.

"BaSE provides water-resource managers with nearly 50 years of daily mean streamflow for ungaged sites in a matter of minutes that they can use for their projects. These daily values can then be used to generate a number of streamflow statistics that may be needed for decision making," said Marla Stuckey, USGS hydrologist and project lead in Pennsylvania.

Water-resource managers use daily mean streamflow to evaluate withdrawal, allocation, and wastewater permit applications and to assess the health of the Commonwealth's streams. Historically, it has been difficult, costly, and time intensive to estimate daily mean streamflow for stream locations that were not gaged, or monitored. Now, BaSE allows users to estimate daily mean streamflow values and daily hydrographs by entering a few basic basin characteristics in an easy-to-use tool. The output is a summary spreadsheet, containing information about the location of interest, including daily mean streamflow for every day from 1960 to 2008.

BaSE relies on a methodology that uses flow-duration curves, which illustrate the percentage of time, or probability, that a flow value in a stream will equal or exceed a particular value. Flow-duration curves are generated for reference streamgage locations with monitored streamflow and the curves are transferred to ungaged locations to estimate daily mean streamflow.

BaSE chooses the most appropriate reference streamgage for the ungaged location and applies newly developed regression equations to convert the transferred flow duration curve to streamflow at the ungaged location.

A USGS Scientific Investigations Report describing BaSE can be found online.

Reminder - Abstracts for the 2013 TMN UC and CDI Workshop Due Soon

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 8 Feb 2013 10:40:27 EDT

Calling for abstracts in support of the The National Map Users Conference and the USGS Community for Data Integration Workshop.

The joint 2013 The National Map Users Conference and Community for Data Integration Workshop will be held on May 20 – 24, 2013 in Denver, Colorado. The event will bring together scientists, partners, managers, and data users to share relevant accomplishments and progress through presentations, workshops, training, posters, and informal gatherings.

Invited guests and representatives from the Department of the Interior (DOI), USGS, and other organizations will provide perspectives on goals, strategic direction, science needs, and training on geospatial science and related activities.

Please consider participating by submitting an abstract that addresses one of the Conference or Workshop session themes. Abstracts should address (1) experiences based on use of The National Map data theme or application and (2) data integration issues, planning, and execution in support of science, including products and tools to help users find, get, and use data for conducting interdisciplinary studies.

Abstract Instructions and Schedule

Abstracts must be submitted through this online form NO LATER THAN February 22, 2013.
Authors will be notified of acceptance by April 1, 2013.
Abstracts are limited to 400 words or less.

Submit today, and we hope to see you in Denver. Questions?

Software Offers Tool to Evaluate Wildlife Fatalities at Wind-Power Facilities

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 11 Dec 2012 14:15:00 EDT

CORVALLIS, Ore.— Resource managers now have a user-friendly tool to estimate wildlife fatalities at wind-power facilities, thanks to software and a user's guide released today by the U.S. Geological Survey. The software combines counts of animal carcasses and detection-rate information to estimate the number of fatalities and to provide measures of uncertainty of these estimates to help managers address concerns about the potential environmental effects of this rapidly expanding industry.

Bird and bat fatalities at some wind-power facilities have led to recommendations and sometimes requirements from state and federal regulators that facility managers monitor wildlife fatalities as a condition for facility development and operation. Usually this monitoring involves searching for carcasses beneath and near turbines.

Unfortunately, simple counts of dead animals do not reflect actual fatality because carcasses are detected at varying rates. Carcasses may be removed by scavenging animals before monitors are able to include them in count information. Some species are inherently easier to detect than others; for example, an eagle is much easier to find than is a hummingbird. Furthermore, carcasses can be obscured by vegetation or fall in steep terrain that is difficult or impossible to search.

In 2010, USGS scientist Manuela Huso published an approach to estimating fatality that accounts for variable detection rates among carcasses. The tool being released today, that Huso and collaborators Nick Som and Lew Ladd of EcoStats, LLC subsequently developed, provides a bridge between the highly technical details of her original publication to the needs of consultants and field managers conducting wildlife monitoring.

"Accurate and unbiased estimates are critical to our understanding of the effects of wind-power facilities on wildlife," Huso said. "They are necessary to compare techniques currently available to managers to reduce fatalities, to assess cumulative effects on wildlife populations, and to develop predictions of potential fatality prior to a facility's construction. Even more important are measures of the uncertainty associated with estimates of fatality, which this software also provides."

This software has its limitations, however. A different set of statistical tools is needed to evaluate fatality of a particular species for which few individuals are expected to be killed but for which accurate estimates of fatality are critical, e.g. rare or endangered species. Huso said the USGS is working to develop these tools as well. Once these tools are available USGS will release them to the public.

The publication is Huso, M.M., Som, N., Ladd, L., 2012, Fatality Estimator User's Guide: U.S. Geological Survey Data Series 729.

Groundwater's Greater Role in Waterways Demonstrated in Virginia

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 26 Nov 2012 9:51:04 EDT

RESTON, Va.— Groundwater in Virginia is a greater contributor to streamflow than calculated by the most commonly used technique, according to recent USGS research.

For decades, hydrologists have used only the changing water levels and flow rates, a graphical hydrograph separation or GHS method, in streams to try to estimate the base-flow component. However, many individual studies during that period that used chemical tracers during isolated storm events suggested that the graphical method was underestimating the groundwater component of the streamflow.

In the newly released study, a broad-spatial scale method was applied that uses specific conductance in addition to flow rates, a chemical hydrograph separation or CHS method, for estimating stream base flows and the components of the water budget in watersheds.

This is the first time scientists have demonstrated that the GHS methods are routinely biased and underestimate the groundwater contribution. The USGS study covered a broad region and examined many months of continuous data to help ensure the accuracy of its findings. The CHS method in Virginia gave an average groundwater component in streams of 70 percent, versus 60 percent by the GHS method.

"Unlike the CHS method with specific conductance, other chemical tracer methods that have been used on individual storm events are too costly to be used over this large of a spatial scale and time period," said Ward Sanford, hydrologist and lead author of the study, "but the CHS method is not well suited for all locations, for example, in streams where there are impoundments of water in reservoirs. This is also a groundbreaking study because it can serve as a model for a national-scale study that estimates water budget components in other states."

Both surface water and groundwater within the Commonwealth of Virginia are allocated based on long- and short-term estimates of water availability. Sanford noted that application of the CHS method in Virginia highlighted the components of the water budget in different counties and watersheds, and can be used for better management and planning of water resources, both surface water and groundwater.

For example, Sanford said, the method could help improve water management in the face of persistent droughts, or could improve models of water quality changes, in response to land- and farming-management practices, as well as best management practices.

New tools, including national climate data sets with a resolution of less than one mile, and cost-effective specific-conductance probes for base-flow separation, are now for any state in the country, and can be used to assess long-term water availability, as demonstrated in this study in Virginia. Such assessments will be valuable for water resource managers at the state, county and local planning levels.

The publication, Quantifying Components of the Hydrologic Cycle in Virginia using Chemical Hydrograph Separation and Multiple Regression Analysis (SIR 2011-5198), is available online.

How Does Groundwater Pumping Affect Streamflow?

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 16 Nov 2012 9:23:42 EDT

New USGS Report Describes Processes and Misconceptions Concerning the Effects of Groundwater Pumping on Streamflow

Groundwater provides drinking water for millions of Americans and is the primary source of water to irrigate cropland in many of the nations most productive agricultural settings. Although the benefits of groundwater development are many, groundwater pumping can reduce the flow of water in connected streams and rivers—a process called streamflow depletion by wells. The USGS has released a new report that summarizes the body of knowledge on streamflow depletion, highlights common misconceptions, and presents new concepts to help water managers and others understand the effects of groundwater pumping on surface water.

"Groundwater discharge is a critical part of flow in most streams--and the more we pump below the ground, the more we deplete water flowing down the stream," said USGS Director Marcia McNutt. "When viewed over the long term, it is one big zero-sum game."

Groundwater and surface-water systems are connected, and groundwater discharge is often a substantial component of the total flow of a stream. In many areas of the country, pumping wells capture groundwater that would otherwise discharge to connected streams, rivers, and other surface-water bodies. Groundwater pumping can also draw streamflow into connected aquifers where pumping rates are relatively large or where the locations of pumping are relatively close to a stream.

"Streamflow depletion caused by pumping is an important water-resource management issue across the nation because of the adverse effects that reduced flows can have on aquatic ecosystems, the availability of surface water, and the quality and aesthetic value of streams and rivers," said Paul Barlow, USGS hydrologist and author on the report. "Managing the effects of streamflow depletion by wells is challenging, particularly because of the significant time delays that often occur between when pumping begins and when the effects of that pumping are realized in nearby streams. This report will help managers understand the many factors that control the timing, rates, and locations of streamflow depletion caused by pumping."

Major conclusions from the report:

Individual wells may have little effect on streamflow depletion, but small effects of many wells pumping within a basin can combine to produce substantial effects on streamflow and aquatic habitats.

Basinwide groundwater development typically occurs over a period of several decades, and the resulting cumulative effects on streamflow depletion may not be fully realized for years.

Streamflow depletion continues for some time after pumping stops because it takes time for a groundwater system to recover from the previous pumping stress. In some aquifers, maximum rates of streamflow depletion may occur long after pumping stops, and full recovery of the groundwater system may take decades to centuries.

Streamflow depletion can affect water quality in the stream or in the aquifer. For example, in many areas, groundwater discharge cools stream temperatures in the summer and warms stream temperatures in the winter, providing a suitable year-round habitat for fish. Reductions in groundwater discharge to streams caused by pumping can degrade habitat by warming stream temperatures during the summer and cooling stream temperatures during the winter.

The major factors that affect the timing of streamflow depletion are the distance from the well to the stream and the properties and geologic structure of the aquifer.

Sustainable rates of groundwater pumping near streams do not depend on the rates at which groundwater systems are naturally replenished (or recharged), but on the total flow rates of the streams and the amount of reduced streamflow that a community or regulatory authority is willing to accept.

"Conjunctive management of groundwater and surface-water resources is critical in New Mexico, where our limited surface-water supplies can be impacted by new uses that are predominantly dependent on groundwater pumping," said Mike Johnson, Chief of the Hydrology Bureau in the New Mexico Office of the State Engineer. "This new USGS publication consolidates our understanding of the connection between aquifers and streams and provides a clear, thorough and up-to-date explanation of the tools and techniques used to evaluate streamflow depletion by wells. This report will be very useful to New Mexico’s water managers in guiding technical analysis, dispelling common misconceptions, and explaining these complex concepts to decision makers and the public."

The report, which is a product of the USGS Groundwater Resources Program, is titled “Streamflow Depletion by Wells—Understanding and Managing the Effects of Groundwater Pumping on Streamflow” and is available in print and online.

The Groundwater Resources Program provides objective scientific information and develops the interdisciplinary understanding necessary to assess and quantify the availability of the nation’s groundwater resources. The Program has been instrumental in documenting groundwater declines and in developing groundwater-flow models for use in sustainably managing withdrawals. The research and understanding developed through this program can provide water-resource managers with the tools and information needed to manage this important natural resource.

Stream Nutrient Reductions from Conservation Practices Not Consistently Detectable Across U.S.

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 23 Oct 2012 9:00:00 EDT

The effects of conservation practices meant to reduce nutrient loss to streams were not consistently detectable in 133 large agricultural watersheds across the U.S. in a new analysis by the USGS.

One explanation for the lack of widespread improvement may be that changes in water quality lag behind the implementation of conservation practices. Lags may be occurring for a number of reasons. Nitrogen from agricultural land moves slowly to streams through groundwater, so it can take several years for reductions in nitrogen inputs on the land surface to affect nitrogen levels in streams.

Nutrient pollution can also be reduced when agricultural land is restored to natural vegetation; however, it takes time for these plants to reach their maximum ability to retain nutrients. Additionally, phosphorus runoff to streams can continue to be an issue even after inputs are reduced on the land surface because of past accumulation in soils.

"The effects of conservation practices are not yet consistently detectable at a large watershed scale," said Lori Sprague, USGS hydrologist and lead author of the study. "Current nutrient conditions in streams may still be reflecting agricultural practices that were in place prior to the implementation of the conservation practices."

The study assessed conservation tillage and the Conservation Reserve Program, both designed to reduce soil runoff and nutrient loss from farmland. Conservation tillage, which limits soil plowing while retaining crop residue on the soil surface, is used on approximately 25 percent of the cropland in the U.S. Approximately eight percent of cropland was enrolled in the Conservation Reserve Program, through which environmentally sensitive farmland is restored to filter strips, grassed waterways, riparian buffers, and long-term vegetative covers, such as introduced or native grasses.

The lack of detectable impact from conservation practices could also be due to an increase in dissolved nutrients from areas in conservation tillage, where fertilizer, manure, and crop residues are not fully incorporated into the soil. Other possible explanations include nutrient runoff from nearby cropland without conservation practices in place and an incomplete characterization of the location and spatial extent of conservation practices.

If changes in nutrient loss from agricultural watersheds do lag implementation of conservation practices, nutrient levels in streams may be reduced in the years beyond the scope of this study, which includes USGS data from 1993 to 2001 paired with conservation data from that time period that has only recently become available. Long-term river monitoring at the large watershed scale can provide future accounting of any changes—lagged or otherwise—resulting from the implementation of conservation practices.

This study was supported by the USGS National Water-Quality Assessment Program, which has assessed the physical, chemical, and biological characteristics of streams, rivers, and groundwater across the Nation since 1991. The article detailing this study, "Relating management practices and nutrient export in agricultural watersheds of the United States," was recently published in the Journal of Environmental Quality and can be found online. Learn about other NAWQA national nutrient assessments.

Landsat Science Team to Help Guide Next Landsat Mission

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 19 Oct 2012 15:13:24 EDT

Landsat satellites have witnessed over four decades of changes on Earth. In advance of the next Landsat spacecraft launch, the Landsat Data Continuity Mission, the U.S. Geological Survey (USGS), in cooperation with the National Aeronautics and Space Administration (NASA), announces the selection of the Landsat Science Team. This expert team of scientists and engineers will serve a five-year term, from 2012-2017, and provide technical and scientific input to USGS and NASA on issues critical to the success of the Landsat program.

"Landsat is a versatile tool that is used by farmers, scientists, and city planners," said Matt Larsen, USGS Associate Director for Climate and Land Use Change. "In fact, it’s used by a broad range of specialists to assess some of the world’s most critical issues — the food, water, forests, and other natural resources needed for a growing world population. This team will help the Landsat program reach its highest potential."

Since 1972, the United States has acquired and maintained a unique, continuous record of the global land surface. This impartial record has become indispensable for detecting and monitoring natural and human-induced changes to the Earth’s landscape.

The Landsat Data Continuity Mission (LDCM), which will become Landsat 8 following launch in February 2013, is designed to extend Landsat’s comprehensive global record for at least five years.

"The team will form a science vanguard in advancing the analysis and application of Landsat data for science and resource management," said Jim Irons, LDCM Project Scientist for NASA. "Their guidance will be invaluable as we plan for the long term future of the Landsat program."

As recognized national and international leaders in land remote sensing, Landsat Science Team members will evaluate operational and data management strategies to meet the requirements of all Landsat users, including the needs of policy makers at all levels of government. They will play a key role in ensuring that the LDCM mission is successfully integrated with past, present, and future remotely sensed data for the purpose of observing national and global environmental systems.

The Landsat Science Team members and their areas of study are:

Developing and enhancing Landsat derived evapotranspiration and surface energy products

Dr. Richard Allen, University of Idaho
Dr. Ayse Kilic, University of Nebraska
Dr. Justin Huntington, Desert Research Institute

Mapping vegetation phenology, water use and drought at high spatiotemporal resolution fusing multi-band and multi-platform satellite imagery

Dr. Martha Anderson, USDA Agricultural Research Service
Dr. Feng Gao, USDA Agricultural Research Service

Understanding the global land-use marketplace

Dr. Alan Belward, European Commission Joint Research Centre

Ecological Applications of Landsat Data in the Context of US Forest Service Science and Operational Needs

Dr. Warren Cohen, USDA Forest Service

Landsat data continuity: advanced radiometric characterization and product development

Dr. Dennis Helder, South Dakota State University

Integrating Field-Level Biophysical Metrics Derived from Landsat Science Products into a National Agricultural Data Warehouse

Dr. Jim Hipple, USDA Risk Management Agency

Synergies between future Landsat and European satellite missions for better understanding coupled human-environment systems

Dr. Patrick Hostert, Humboldt University of Berlin

Operational monitoring of US croplands with Landsat 8

Mr. David Johnson, USDA National Agricultural Statistical Service

Using time-series approaches to improve Landsat’s characterization of land surface dynamics

Dr. Robert Kennedy, Boston University

Multi-temporal Analysis of biophysical parameters derived from the Landsat Series of satellites

Dr. Leo Lymburner, Geoscience Australia

Absolute radiometric and climate variable intercalibration of Earth observing sensors

Dr. Joel McCorkel, NASA Goddard Space Flight Center

Continuity of the Web Enabled Landsat Data (WELD) Product Record in the LDCM Era

Dr. David Roy, South Dakota State University

North American Land Surface Albedo and Nearshore Shallow Bottom Properties from Landsat and MODIS/VIIR

Dr. Crystal Schaaf, University of Massachusetts, Boston

Cryospheric Applications of the Landsat Data Continuity Mission (Landsat 8)

Dr. Ted Scambos, University of Colorado

The Use of LDCM for the Monitoring of Fresh and Coastal Water

Dr. John Schott, Rochester Institute of Technology

Developing Decadal High Resolution Global Lake Products from LDCM and Landsat

Dr. Yongwei Sheng, University of California, Los Angeles

Development of Landsat surface reflectance Climate Data Records

Drs. Eric Vermote and Christopher Justice, University of Maryland

Ecological Disturbance Monitoring using Landsat Time Series Data

Dr. Jim Vogelmann, U.S. Geological Survey

Better Use of the Landsat Temporal Domain: Monitoring Land Cover Type, Condition and Change

Dr. Curtis Woodcock, Boston University

Integrating the past, present, and future of Landsat

Dr. Mike Wulder, Canadian Forest Service

Making Multitemporal Work

Dr. Randolph Wynne, Virginia Tech

Further information

International Landsat Cooperators to Confer in Sioux Falls

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 19 Sep 2012 11:41:17 EDT

Global coordination advanced through longstanding annual meeting

As Landsat continues to circle Earth, international partners of the Landsat program in almost a dozen locations downlink and process the data, sharing images with a global community of scientists, engineers, and land managers. These partners meet annually for the Landsat Technical Working Group (LTWG) meeting, which will be held this year in Sioux Falls, S.D., Sept. 24-28. LTWG serves as a venue to discuss operational and technical issues and explore expanded opportunities for collaboration.

This meeting, the twenty-first for the group, will concentrate on establishing reception, processing and distribution capabilities for the next Landsat satellite. The Landsat Data Continuity Mission (LDCM) is set for launch in early February 2013. The state-of-the-art imaging satellite — to be known as Landsat 8 once it successfully achieves orbit— will build on the 40-year record of Earth observations by the Landsat satellite series and greatly expand the program’s capabilities to impartially record changes on the surface of the Earth.

Conference organizers at the U.S. Geological Survey Earth Resources Observation and Science Center (USGS-EROS) anticipate nearly 140 participants in the meeting from 25 countries and 49 separate organizations.

One Click Away: Finding Data on Florida's Endangered Species Just Got Easier

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 18 Sep 2012 9:50:58 EDT

Davie, FL. -- A new online tool will make data on several of Florida’s threatened and endangered species—including the Florida panther, American crocodile, and Key deer—more readily accessible to resource managers and planners.

The tool, a searchable database known as "Threatened and Endangered Vertebrates in Florida," was developed by a team of researchers from the University of Florida, the U.S. Fish and Wildlife Service, the U.S. Geological Survey, and the National Park Service.

It allows scientists and conservation managers to query an online database housing key scientific facts about the biology and ecology of 26 species of federally-listed threatened and endangered terrestrial vertebrates in Florida. The database query tool can be accessed online.

“We were gathering data for a project to assess how species respond to climate variables when we realized how valuable it would be to other scientists and managers if we could develop a tool to make the data more accessible," explained research ecologist Stephanie Romañach, PhD, who works for the USGS Southeast Ecological Science Center.

By querying the database, users will be able access species-specific information that can be used to guide research projects, develop ecological models, conduct species vulnerability assessments, and inform conservation action plans. The database includes almost 10,000 lines of data grouped into 10 major categories based on important biological traits, including reproduction, migration, and dispersal, as well as species’ relationships to climate variables such as temperature, precipitation, salinity, and responses to extreme weather.

"It is an incredibly useful tool for anyone wanting to learn more about some of the Florida's wildlife," said Larry Williams, South Florida Ecological Service Field Supervisor with the U.S. Fish and Wildlife Service. "This enhanced research capacity will undoubtedly contribute greatly towards all of our efforts to protect and preserve the natural wonders of Florida for future generations."

The database was implemented by the Advanced Applications Group at the USGS National Wetlands Research Center, and has been made available to the public by Joint Ecosystem Modeling (JEM), a partnership among federal and state agencies, universities, and other organizations. JEM activities include the monitoring and management of wildlife populations, understanding species responses to ecosystem restoration, and developing decision-support tools for restoration decision-making.

"Science excellence and collaborative partnerships are two pillars of our wildlife conservation culture," said Williams "This database enhances our ability to share and gather science from a wider spectrum of partners to the benefit of the imperiled species we're recovering across Florida."

The research team who developed the database links science to management by developing tools that support restoration and management decisions, species conservation, and climate change issues. Their approach includes the application of species distribution models to forecast the effects of land use, habitat alteration, and climate change on at-risk species, the use of life-history assessments to understand trait-mediated species responses to climate change and disturbance, incorporating climate sensitivities into species habitat and population models, and the assessment of species vulnerability to sea-level rise.

For more information about the JEM team’s projects, visit the JEM website or the University of Florida Institute of Food and Agricultural Sciences CrocDocs website.

New Reports Update Estimates of Flood Frequency in California

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 27 Aug 2012 11:00:00 EDT

SACRAMENTO, Calif. — The U.S. Geological Survey has released updated flood frequency estimates for select rural "natural flow" California streams throughout the state. The estimates are based on greatly expanded data and documented in three reports available online. These reports from the USGS and its partners represent an important resource for emergency officials, water managers and civil engineers.

The first report, prepared in cooperation with the Federal Emergency Management Agency, the U.S. Army Corps of Engineers, and the U.S. Forest Service, provides a new regional equation to help characterize peak flows throughout California by using historical and recent flood data with updated statistical methodologies to calculate flood magnitude and frequency. This regional equation, based on data from 158 streamgages through 2005, takes into account elevation and the complex interaction of rain, snow and flood hydrology of California mountains on the frequency and magnitude of large floods. Using this new regional equation, the report also provides updated flood estimates for streams monitored by USGS streamgages primarily in the Sacramento-San Joaquin River basin.

Building on the regional equation established in the aforementioned report, the second report develops new statewide prediction equations for determining the magnitude and frequency of annual instantaneous peak flows using data from 769 streamgages throughout California. The report provides estimates of the annual exceedance probability flood flows – the probability of a certain size flood being equaled or exceeded in a given year – at these 769 locations. Together, these two reports replace previous prediction equations that were last updated more than 30 years ago. This new analysis may be used by the public and private sectors for everything from water management to insurance estimations.

"Pacific storms can deliver rainfall to California at rates that rival hurricanes of the Gulf coast, creating the potential for both human and high-dollar disasters across the California landscape," said USGS Director Marcia McNutt. "Furthermore, modifications that are made to drainage systems in the process of land development and from natural events can modify flood potential. Based on updated information and improved methods, these new flood-frequency estimates will help Californians reduce or avoid losses to life and property."

The third report, prepared in cooperation with the U.S. Army Corps of Engineers, focuses on sustained flood flow (flood duration), which is needed to assess the adequacy of reservoirs, levees and other flood-control structures. Using data through 2008, the report examines annual maximum floods for 1-day, 3-day, 7-day, 15-day and 30-day durations at 50 dams and streamgages throughout the Sacramento-San Joaquin River basin and adjacent regions. Applying updated statistical methodologies to these data, the report provides new regional equations to help characterize flood-duration flows.

"At FEMA, we are constantly working to increase the level of recognition of all hazards, including flooding, by communicating the steps that the whole community can take to prevent or mitigate those threats," said FEMA Region IX Administrator Nancy Ward. "The scientists at USGS and USACE are to be commended for helping to inform California’s communities of the flood hazards they face."

USGS operates more than 8,400 streamgages needed by federal, state and local agencies and the private sector to design and operate water-supply, wastewater treatment, hydropower, and irrigation infrastructure, and conducts studies to extend the utility of these data and related purposes.