#  Begin METADATA documentation
# ------------------------------------------------------------------------------------------------------
#  DATASET_NAME: 	MRB5_pop_dens.txt
#  DATASET_DESCRIPTION:	This data set was used as part of a nutrient, sediment, and streamflow trend 
#			assessment for the Lower-Mississippi, Arkansas-White-Red, Texas-Gulf Basins.
#  DATA_SET FORMAT:	Tab-delimited ascii file
#  DATA_SET URL:
#
# ------------------------------------------------------------------------------------------------------ 
#  REPORT TITLE: 	Trends in Nutrient and Sediment Concentrations and Loads in Major River Basins
#			of the South-Central United States, 1993-2004    
#  REPORT SERIES/NUMBER (JOURNAL NAME/VOLUME): USGS Scientific Investigation Report (SIR 2007-5090)     
#  REPORT URL:		http://pubs.usgs.gov/sir/2007/5090/
#
# ------------------------------------------------------------------------------------------------------
#  NAWQA STUDY:		Major River Basin 5
#
# ------------------------------------------------------------------------------------------------------
#
#  METADATA DATE:    	July, 2008
#  METADATA CONTACT: 	Richard A. Rebich
#                    	USGS-WRD, Mississippi Water Science Center 
#                    	308 South Airport Road
#	 	     	Jackson, MS  39208-6649	
#                    	voice: 601-933-2928
#                    	fax:   601-933-2901
#                    	email:  rarebich@usgs.gov
#
#  SECONDARY CONTACT:   Dennis Demcheck
#                    	USGS-WRD, Louisiana Water Science Center 
#                    	3535 S. Sherwood Forest Blvd., Suite 120
#	 	     	Baton Rouge, LA  70816	
#                    	voice: 225-298-5481, ext.3214
#                    	fax:   225-298-5490
#                    	email:  ddemchec@usgs.gov
#
# ------------------------------------------------------------------------------------------------------
#  METADATA Data Description:  
#
#  ABSTRACT:  
#	This file documents trend values for population density ancillary data for water-quality 
#	stations used in the report, "Trends in Nutrient and Sediment Concentrations and Loads in Major 
#	River Basins of the South-Central United States, 1993-2004," by Rebich and Demcheck, USGS 
#	Scientific Investigation Report (SIR 2007-5090), located at http://pubs.usgs.gov/sir/2007/5090/.  
#
#	The information presented here is summarized as a decadal difference for population density 
#	at each station.  Population density data were used as a surrogate to estimate potential
#	trends in point sources for the study area.
#	The first step to determine trends in the population density data was to delineate drainage area 
#	boundaries at each site.  The drainage area boundaries were used as digital polygon overlays 
#	to partition the GIS-derived data at each station.  The population data were then 
#	entered into a spreadsheet, and a difference was calculated for each station.  The
#	population density data were already normalized by drainage area.  The differences 
#	were then plotted for the study area and then related to trends in water-quality data using 
#	weighted-least-squares (WLS) regression analysis.  Input and results for WLS analyses are found 
#	in files MRB5_WLS_input.txt and MRB5_WLS_results.txt, repsectively.
#
#	The drainage basin boundaries and population datasets for each water-quality station were obtained 
#	from one of 2 NAWQA websites (http://water.wr.usgs.gov/pnsp/gis/data/swancil/mrb.html, or 
#	http://water.wr.usgs.gov/pnsp/gis/data/swancil/cycle2.html).  These two websites contained 
#	data that had originally been compiled from other external sources.  Datasets and analysis 
#	techniques are further described in Rebich and Demcheck, 2007 (SIR 2007-5090).  
#
# -------------------------------------------------------------------------------------------------------
#
#  METADATA detailed documentation of dataset elements:
#
#	Column headings are as follows:
#
#	STAID:				Station identification number for the water quality trend sites
#					used in this study as specified in MRB5A_wq_site_list.txt.
#
#	Latutude:			Decimal latitude of each water-quality station
#
#	Longitude:			Decimal latitude of each water-quality station
#
#	1990_people_per_sqkm:		1990 population density for each water-quality station based on 
					overlays of drainage area polygons on spatial census data,
					expressed as people per square kilometer located within the
					drainage area boundary for each station.
#
#	2000_people_per_sqkm:		2000 population density for each water-quality station based on 
					overlays of drainage area polygons on spatial census data,
					expressed as people per square kilometer located within the
					drainage area boundary for each station.
#
#	Decadal_change_people_per_sqkm:	Difference between 1990 and 2000 population density data 
					representing the net change in populatoon within the drainage
					area boundary for each water-quality station.  Positive and
					negative values represent increases and decreases in population
					at each station. Values are expressed in people per square
					kilometer.
#
#  End METADATA documentation
# ------------------------------------------------------------------------------------------------------
#
#
#  BEGIN DATA: MRB5_pop_dens.txt
# ------------------------------------------------------------------------------------------------------
STAID	Latitude	Longitude	1990_people_per_sqkm	2000_people_per_sqkm	Decadal_change_people_per_sqkm
07047942	35.1445342	-90.87844884	15	16	1
07050500	36.42599167	-93.62319167	7	9	2
07052250	37.00657222	-93.36467778	142	173	31
07053250	36.45395515	-93.35657255	16	20	4
07055646	35.94535571	-93.40351603	2	1	-1
07056000	35.983175	-92.74755278	4	4	0
07060500	36.11618113	-92.1432091	18	23	5
07060710	35.99535053	-92.21265464	2	2	0
07061600	37.32504888	-90.76400933	3	3	0
07077700	35.25203152	-91.11040004	29	32	3
07093740	38.65888469	-105.8138942	0	0	0
07103700	38.85471357	-104.8780314	42	49	7
07103780	39.03110354	-104.8483128	41	68	27
07104905	38.83721474	-104.8294192	262	349	87
07105500	38.81638158	-104.8227519	175	236	61
07105530	38.80304911	-104.7958069	231	293	62
07106300	38.43972236	-104.5935833	172	221	49
07106500	38.28778013	-104.6010849	167	212	45
07189000	36.63146139	-94.5868886	22	33	11
07195500	36.13008194	-94.5721644	72	106	34
07195865	36.2017483	-94.6052206	151	189	38
07196000	36.1864725	-94.7068914	46	60	14
07196500	35.92286889	-94.9235658	55	80	25
07196900	35.88008235	-94.48660625	11	14	3
07197000	35.92120028	-94.8385633	10	13	3
07227500	35.47032612	-101.8796281	2	2	0
07228000	35.935042	-100.3706884	3	3	0
07239450	35.6169933	-98.0653317	3	3	0
07241000	35.4786686	-97.6633753	5	6	1
07241520	35.5656147	-97.367258	13	13	0
07241550	35.5003411	-97.1939194	13	14	1
07247015	34.87982389	-94.4841111	9	10	1
07247250	34.7737147	-94.5121686	3	4	1
07247345	34.8431572	-94.6246706	3	4	1
07247650	34.91982139	-94.9455125	9	9	0
07249400	35.16259588	-94.40716074	14	17	3
07268000	34.4825	-89.22444444	21	25	4
07288650	33.39666667	-90.84777778	13	14	1
07288955	32.48736331	-90.81732511	16	17	1
07290650	32.0186111	-90.8783333	11	12	1
07299540	34.56922728	-100.1940023	8	9	1
07300000	34.95755294	-100.2209491	1	1	0
07308500	34.11009327	-98.53172335	6	6	0
07311700	33.82064216	-99.78648219	1	1	0
07311800	33.64425703	-99.80092517	0	0	0
07331000	34.2334272	-96.9758447	8	8	0
07335500	33.875105	-95.5019022	9	9	0
07337000	33.55206716	-94.04130093	9	9	0
07343000	33.47483009	-95.5877347	6	6	0
07362000	33.59650222	-92.81821802	12	14	2
07362587	34.79731348	-92.93350737	3	8	5
07373000	31.5362873	-92.40847139	14	15	1
07375500	30.50658047	-90.3617524	27	30	3
07381600	29.70270795	-91.20204757	21	22	1
07385765	29.87937163	-91.5862248	38	39	1
07386980	29.9511111	-92.1563611	175	199	24
08012150	30.19	-92.5905556	33	35	2
08030500	30.30381684	-93.7437784	20	22	2
08032000	31.89239037	-95.43078599	33	39	6
08033500	31.025	-94.39944444	21	24	3
08041000	30.35576378	-94.0932373	20	23	3
08044500	33.08539917	-97.558636	9	11	2
08049500	32.7987406	-97.02973015	133	157	24
08051500	33.3362269	-97.1794587	6	8	2
08057410	32.70763139	-96.73583187	176	227	51
08062500	32.42652988	-96.46304152	185	240	55
08064100	32.19848231	-96.52026387	28	37	9
08065000	31.64850597	-95.7894029	124	161	37
08065350	31.33851319	-95.65634069	116	150	34
08066500	30.4252067	-94.8507622	96	125	29
08069000	30.0357753	-95.428827	182	256	74
08073500	29.7618958	-95.6057782	225	366	141
08074500	29.77522777	-95.3971612	987	1220	233
08078000	29.3694046	-95.3207697	30	45	15
08085500	32.9345557	-99.2245215	15	16	1
08114000	29.5824589	-95.75772753	16	19	3
08117500	29.31357967	-95.8938421	10	11	1
08123850	32.05374399	-100.762052	12	12	0
08136500	31.51599082	-99.91952257	7	7	0
08143600	31.5173861	-98.740603	9	9	0
08147000	31.21794515	-98.564484	8	8	0
08154700	30.37214825	-97.78473012	420	664	244
08155200	30.29631587	-97.92556496	18	36	18
08155240	30.27409573	-97.84472961	31	56	25
08155300	30.24465306	-97.80222831	47	91	44
08156800	30.27659704	-97.75028338	1660	1813	153
08159000	30.17798987	-97.6886138	150	214	64
08162000	29.30913668	-96.1038482	13	16	3
08162500	28.9741462	-96.0124588	13	16	3
08162600	28.92803769	-96.1710747	29	30	1
08178565	29.32218127	-98.4502932	1698	1760	62
08178800	29.35718017	-98.41279255	508	624	116
08181800	29.22218531	-98.35584627	247	289	42
08188500	28.64971485	-97.3847152	127	151	24
08189500	28.29195088	-97.2791593	3	5	2
08210000	28.42749545	-98.17806252	3	4	1
