Chemistry of the Spring Waters of the Ouachita Mountains Excluding Hot Springs, Arkansas

This report is based on the chemical analysis of the waters from 93 springs and 9 wells. Springs, when free from metal plumbing, provide an uncontaminated source of the ground water and it was desired to obtain water uncontaminated with metals. A few wells were added to the list, usually because of their unique location in the sampling grid

Nutrients and Acid in the Rain and Dry Fallout at Fayetteville, Arkansas (1980-1982)

Wet and dry fallout at Fayetteville, Arkansas have been collected separately and analyzed since April, 1980. The precipitation-weighted-average pH for two yearly periods of rainfall were 4.72 (6/80-5/81) and 4.75 (6/81-5/82). This corresponds to a concentration of the acid ion, H+, of about 18 parts per billion (ppb). Pure water in equilibrium with the CO2 of the air would have a pH of 5.65 (2.2 ppb of H+). The range of pH during this two year period was 3.86-7.74(140-0 ppb H+) for the rainfall. Aqueous extracts of the dry fallout were always in the 6.75-7.87 pH range, i.e., neutral to slightly alkaline. The slight amount of acidity in the Fayetteville rainfall should be easily neutralized by dry fallout and soil. Ammonium bisulfate, NH4HSO4, is the major acidic chemical in the rains. Sulfur tends to increase in winter months presumably due to the greater use of fossil fuels. Northern rains have the most acidity. Wet and dry fallout add significant amounts of nutrients to the local soils with 25-87% of the total flux being dry fallout. A. major contributor are dust storms which bring in soil from adjacent states. Iron and zinc were the most prevalent heavy metals in the wet fallout. Their concentrations were very low averaging less than 10 ppb for Fe and 15 ppb for Zn. Northernly and southernly rains had the most Fe and Zn and correspond to directions in which there are smelters

Nitrogen fertilization of soybeans

Cover title.Digitized 2007 AES.Includes bibliographical references (page 23)

Trace Metals and Major Elements in Water-Soluble Rocks of Northwest Arkansas

Trace metals in limestone are potential water contaminants because they can enter the ground water when the limestone is dissolved by carbonic acid and other naturally occurring acids. Four local limestones, the St. Joe and Pitkin Formations (Mississippian) and the Brentwood and Kessler Members of the Bloyd Formation (Pennsylvanian) were sampled in a five county area in Northwest Arkansas. Atomic absorption analyses were made for Na, K, Mg, Ca, Zh, Cu, Ba, Fe, Co, Cr, Ni, Mn, Li and Sr on the acid soluble material of the samples. All the limestones are relatively pure CaCO3 with Pitkin the purest, 93.4%. Calcium and acid soluble material values varied only 3-5% from the average among the limestones whereas 71-108% variation occurred for Fe, Mn, K and Cr. Other elements showed intermediate variations. Only Fe and Mn are present on the average in the limestones at concentration levels which might lead to contamination of ground water to undesirably high levels. Analyses compare well with the reported average limestone except for acid insoluble elements which were not dissolved in our scheme and lithium (1.5 ppm average vs 20 in reference). Ratios of Sr/Ca and Mg/Ca were similar to reported values for limestones of comparable geologic age. Maxima in the areal variation of these ratios occurred at about the same latitude for three of the formations. The areal variation of Fe/Ca and Mn/Ca was also determined for the four limestone formations. Interelement correlations in the limestones showed: Na, Sr, Li, Fe and Zn contents increased with Mg content; Mn and Cr increased with Fe content. Indications were obtained that detrital and other materials not in the calcite structure can be determined by their relative insolubility in acetic acid compared to hydrochloric acid

Trace Element Composition of Stream Sediments an Integrating Factor for Water Quality

Bottom sediments, suspended sediments, and water were sampled along 130 miles of the Buffalo River in northern Arkansas. The water and acid extracts of the suspended sediments and the minus 95 mesh fraction of the bottom sediments were analyzed by atomic absorption spectrometry. All samples were analyzed for Na, K, Mg, Ca, Zn, Cd, Cu, Pb, Fe, Co, Cr, Ni, and Mn. Selected bottom samples also were analyzed by As, Hg, and Zr. Zr was determined by x-ray fluorescence. Li and Sr were determined for selected water and suspended sediment samples. There is a general decrease downstream in Fe, Cu, Cr, Ni, Mn, Pb, K, and Na in the bottom sediments as the drainage area increases in carbonate rock and decreases in shale. The elements Mg, Ca, Zn, and Cd increase in bottom sediments downstream. The values for these elements in the water, especially the major elements, also correspond closely with the geology of the region. Tributaries are sites of abrupt rise and fall of metal values, within a few miles, from background to anomalously high values to background, especially tributaries draining Zn and Pb mineralized areas. The bottom sediments are mainly quartz and chert grains. These grains apparently are coated with hydrous iron oxide which acts as a sorbent for many of the elements and is a dominant transport mechanism for acid extractable Co, Cr, Ni, Cu, Mn, and K. Other acid extractable metals, particularly Mg, Ca, Zn, Cd, and Pb, are mostly in clastic grains. Graphic representation of the Langmuir equation for Mn is consistent with adsorption of Mn by iron in both bottom sediments and suspended sediments. On the basis of the volume of water collected, all the elements except Fe are more concentrated in the water than in the suspended sediments. Fe concentration of the suspended sediments increases with increasing flow because the suspended load is increased. The Mn/Fe ratio of the suspended sediments is approximately equal to or greater than that of the bottom sediments. The Mn/Fe ratio of suspended sediments relative to that of the bottom sediments increases downstream, possibly because of an autocatalytic effect of Mn precipitation. The relationship between sediment and water concentrations is not clear from the data because of the restricted concentration ranges for some elements in the suspended sediment and water. The sediment from the Buffalo River can be used to estimate grossly the concentration of elements in the water

Recovery of fertilizer nitrogen from soils

The bulletin reports on Department of soils research project 178, Soils and Nutrition--P. [2].Digitized 2007 AES.Includes bibliographical references (page 28)

1974 Nonflood-Stage Chemical Loads of the Buffalo River, Arkansas

Dissolved Ca, Mg, Na, K, Fe, Mn, and Zn loads of the Buffalo River generally show trends along the river attributable to changes in geology and vary with the season because of concentration by evapotranspiration and dilution by rain. Suspended material element loads show neither seasonal trends nor trends along the river. The Fe load for the river is predominantly in the suspended material, the Mn load is divided approximately evenly between dissolved and suspended material, and Ca, Mg, Na, K, and Zn are predominantly in the dissolved load