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At least 1,189 records · Page 66Linked to original sources
USGS1997

Trends in acetochlor concentrations in surface waters of the White River Basin, Indiana, 1994–96

Corn herbicides are used extensively in the White River Basin and account for about 70 percent of the total agricultural pesticide use in the basin. Acetochlor, a corn herbicide registered for use in 1994, is expected to reduce the total amount of corn herbicides used because of its broad-spectrum weed control and low use rates. Acetochlor is considered to be a probable human carcinogen, and its continued registration is contingent on concentrations in surface and ground water not exceeding target levels. During 1994, acetochlor was detected in only trace concentrations near the mouth of the White River and not at all in a small stream (93-square-mile drainage) in the northern part of the basin. By 1996, peak concentrations were about 2 and 3 micrograms per liter near the mouth of the White River and in the small stream, respectively. The estimated annual average concentration of acetochlor near the mouth of the White River in 1996 was 0.15 micrograms per liter, well below the 2 micrograms per liter criterion for surface-water supplied community-water systems.

Indiana↗
USGS2005

Streamflow trends in the United States...from the National Streamflow Information Program

This Fact Sheet is one in a series that highlights information or recent research findings from the USGS National Streamflow Information Program (NSIP). The investigations and scientific results reported in this series require a nationally consistent streamgaging network with stable long-term monitoring sites and a rigorous program of data quality assurance, management, archiving, and synthesis. NSIP produces multi-purpose, unbiased surface water information that is readily accessible to all.

Fact Sheet↗
USGS2005

Trends in the water budget of the Mississippi River basin, 1949-1997

This Fact Sheet is one in a series that highlights information or recent research findings from the USGS National Streamflow Information Program (NSIP). The investigations and scientific results reported in this series require a nationally consistent streamgaging network with stable long-term monitoring sites and a rigorous program of data quality assurance, management, archiving, and synthesis. NSIP produces multi-purpose, unbiased surface water information that is readily accessible to all.

Fact Sheet↗
USGS2009

Water Use in Georgia by County for 2005; and Water-Use Trends, 1980-2005

Water use for 2005 for each county in Georgia was estimated using data obtained from various Federal and State agencies and local sources. Total consumptive water use also was estimated for each county in Georgia for 2005. Water use is subdivided according to offstream and instream use. Offstream use is defined as water withdrawn or diverted from a ground- or surface-water source and transported to the place of use. Estimates for offstream water use include the categories of public supply, domestic, commercial, industrial, mining, irrigation, livestock, aquaculture, and thermoelectric power. Instream use is that which occurs within a stream channel for such purposes as hydroelectric-power generation, navigation, water-quality improvement, fish propagation, and recreation. The only category of instream use estimated was hydroelectric-power generation. Georgia law (the Georgia Ground-Water Use Act of 1972 and the Georgia Water Supply Act of 1978 [Georgia Department of Natural Resources, 2008a,b]) requires any water user who withdraws more than 100,000 gallons per day on a monthly average to obtain a withdrawal permit from the Georgia Environmental Protection Division. Permit holders generally must report their withdrawals by month. The Georgia Water-Use Program collects the reported information under the withdrawal permit system and the drinking-water permit system and stores the data in the Georgia Water-Use Data System.

Fact Sheet↗
USGS2009

Status and trends of the Grand Canyon population of Humpback Chub

The Colorado River Basin supports one of the most distinctive fish communities in North America, including the federally endangered humpback chub (Gila cypha). One of only six remaining populations of this fish is found in Grand Canyon, Arizona. U.S. Geological Survey scientists and their cooperators are responsible for monitoring the Grand Canyon population. Analysis of recently collected data indicates that the number of Grand Canyon adult humpback chub - fish 4 years old and older and capable of reproduction - increased approximately 50 percent between 2001 and 2008. When possible model error is considered, the estimated number of adult chub in the Grand Canyon population is between 6,000 and 10,000. The most likely number is estimated at 7,650 individuals.

Arizona↗
USGS2011

A climate trend analysis of Sudan

Summer rains in western and southern Sudan have declined by 10-20 percent since the mid-1970s. Observed warming of more than 1 degree Celsius is equivalent to another 10-20 percent reduction in rainfall for crops. The warming and drying have impacted southern Darfur and areas around Juba. Rainfall declines west of Juba threaten southern Sudan's future food production prospects. In many cases, areas with changing climate are coincident with zones of substantial conflict, suggesting some degree of association; however, the contribution of climate change to these conflicts is not currently understood. Rapid population growth and the expansion of farming and pastoralism under a more variable climate regime could dramatically increase the number of at-risk people in Sudan over the next 20 years.

Fact Sheet↗
USGS2012

A climate trend analysis of Chad

This brief report, drawing from a multi-year effort by the U.S. Agency for International Development (USAID) Famine Early Warning Systems Network (FEWS NET), identifies significant decreases in rainfall and increases in air temperature across Chad, especially in the eastern part of the country. These analyses are based on quality-controlled station observations. Conclusions: * Summer rains have decreased in eastern Chad during the past 20 years. * Temperatures have increased by 0.8 °Celsius since 1975, amplifying the effect of droughts. * Crop yields are very low and stagnant. * The amount of farmland per person is low, and decliningrapidly.* Population growth combined with stagnating yieldscould lead to a 30 percent reduction in per capita cereal production by 2025.* In many cases, areas with changing climate are coincident with zones of substantial conflict, indicating some degree of association; however, the contribution of climate change to these conflicts is not currently understood.

Fact Sheet↗
USGS2012

A Climate Trend Analysis of Niger

This brief report, drawing from a multi-year effort by the U.S. Agency for International Development (USAID) Famine Early Warning Systems Network (FEWS NET), identifies a substantial recovery of rainfall in Niger, accompanied by increases in air temperatures. These analyses are based on quality-controlled station observations. Conclusions: * Summer rains have increased during the past 20 years and have almost returned to 1960-89 levels. * Temperatures have increased by 0.6° Celsius since 1975, amplifying the effect of droughts. * Crop yields are very low and stagnant, and the population is growing very rapidly. * Niger has offset very rapid population growth with a large expansion of cultivated land. * If the expansion of farmland slows down, stagnant yields and population growth could lead to increased food insecurity.

Fact Sheet↗
USGS2023

Tracking status and trends in seven key indicators of stream health in the Chesapeake Bay watershed

“The Bay Connects us, the Bay reflects us” writes Tom Horton in the book “Turning the Tide—Saving the Chesapeake Bay”. The Chesapeake Bay watershed contains the largest estuary in the United States. The watershed stretches north to Cooperstown, New York, south to Lynchburg and Virginia Beach, Virginia, west to Pendleton County, West Virginia, and east to Seaford, Delaware, and Scranton, Pennsylvania. The watershed is more than 64,000 square miles that contain 150 major rivers and streams, hereafter referred to collectively as streams, that total more than 100,000 miles in length. The watershed contains thousands of smaller creeks and tributaries, large numbers of plants and animals, and, in 2020, more than 18.4 million people. As changes occur in population, land use, and climate within the watershed, so too do the diversity and health of the Bay's ecosystems.

Chesapeake Bay watershed↗
USGS2024

The U.S. Geological Survey National Atmospheric Deposition Program, National Trends Network—2022

The U.S. Geological Survey (USGS) has been a National Atmospheric Deposition Program (NADP) partner agency since 1981. NADP is comprised of five atmospheric monitoring networks that verify Clean Air Act effectiveness and provide essential data to protect human health and preserve ecosystems for current and future generations. Stakeholders include land management agencies overseeing sensitive habitats (National Park Service, Bureau of Land Management, U.S. Forest Service, and First Nations), Federal and State regulatory agencies, and the public.

continental United States↗
USGS2025

The U.S. Geological Survey National Atmospheric Deposition Program, National Trends Network, 2023

The U.S. Geological Survey (USGS) has been a National Atmospheric Deposition Program (NADP) partner agency since 1981. NADP is composed of five atmospheric monitoring networks that verify Clean Air Act effectiveness and provide essential data to protect human health and preserve ecosystems for current and future generations. Stakeholders include land management agencies overseeing sensitive habitats (the National Park Service, Bureau of Land Management, U.S. Forest Service, and Tribes), Federal and State regulatory agencies, and the public.

Contiguous United States↗