|
|
These data were released prior to the October 1, 2016 effective date for the USGS’s policy dictating the review, approval, and release of scientific data as referenced in USGS Survey Manual Chapter 502.8 Fundamental Science Practices: Review and Approval of Scientific Data for Release. Generalized lithology (rock type) and physiography based on geologic formations were used to characterize hydrgeomorphic regions (HGMR) within the Chesapeake Bay watershed. These HGMRs were used in conjunction with existing data to assess the significance of ground-water discharge as a source of nitrate load to nontidal streams in the Chesapeake Bay watershed (Bachman and others, 1998). This work is part of the U.S. Geological Survey's...
Categories: pre-SM502.8;
Tags: (keyword) Chesapeake Bay,
(keyword) Geology,
(keyword) HGMR,
(keyword) Hydrogeomorphic Region,
(keyword) Lithology, All tags...
(keyword) Mid-Atlantic,
(keyword) Physiographic,
(keyword) Physiography,
(keyword) Province,
(keyword) Rock,
(keyword) Rock Type,
NSDI,
USGS Science Data Catalog (SDC),
environment,
geoscientificInformation,
inlandWaters,
inlandWaters, Fewer tags
|
This data set contains county-level estimates of nitrogen and phosphorus from fertilizer, for both farm and nonfarm uses, for the conterminous United States, for 1987 through 2012. State-level farm and nonfarm nitrogen and phosphorus were derived from the Association of American Plant Food Control Officials (AAPFCO) commercial fertilizer sales data. State estimates were then allocated to the county-level using fertilizer expenditure from the Census of Agriculture as county weights for farm fertilizer, and effective population density as county weights for nonfarm fertilizer. Data computations for 2007 - 2012 estimates are results of methods applied directly from Gronberg and Spahr, 2012. Data for 1987 - 2006 are...
Categories: Data;
Types: Citation;
Tags: Agricultural,
Conterminous United States,
Ecology,
Farm,
Fertilizer, All tags...
Geography,
Land Use Change,
National Water Quality Program,
Nitrogen,
Nutrient,
Phosphorus,
USGS Science Data Catalog (SDC),
Water Quality,
Water Resources,
inlandWaters,
nonFarm, Fewer tags
|
|
