The distribution of nitrogen species in polluted Onondaga Lake,N.Y., U.S.A.

The temporal and vertical distributions of four N species, N0₃ ^?, NO₂ ^?, total ammonia (T-NH₃), and free ammonia (NH₃), are documented for Onondaga Lake, an urban, polluted, hypereutrophic, dimictic, lake that receives a very high load of T-NH₃. Nitrate and NO₂ ^? were lost rapidly from the hypolimnion, and T-NH₃ accumulated to high concentrations (maximum > 10 mgN L^?1), after the onset of anoxia, consistent with the lake's high level of productivity. The concentrations of T-NH₃, NH₃ and N0₃ ^? that were maintained in the epilimnion (average concentrations at a depth of 1 m of 2.81, 0.16 and 0.91 mgN L^?1, respectively), and concentrations of N0₂ ^? that developed in the epilimnion (maximum of 0.48 mgN L^?1), were high in comparison to levels reported in the literature. These elevated concentrations are largely a result of the extremely high loads of T-NH₃, and its precursors, received by the lake. Water quality problems in the lake related to the prevailing high concentrations of N species include potential toxicity effects and severe lake-wide oxygen depletion during fall turnover.     

The density of inflows to Onondaga Lake,U.S.A., 1980 and 1981

The temporal distributions of the densities of inflows to Onondaga Lake were calculated for the spring to fall period of 1980 and 1981, and compared to the attendant density stratification in ion enriched Onondaga Lake. The industrial utilization of the lake resulted in substantial density differences between the inflows and the lake. Inflows carrying substantial fractions of industrial ionic waste were more dense than the lake, and at times plunged to stratified layers. Water withdrawn from the lower layers of the lake for industrial cooling was displaced to the upper layers as a result of heating. Dilute fluvial inflows were substantially less dense than the lake. The density differences between the inflows and the lake were largely responsible for the rather unique features of density stratification documented for the lake in 1980, and are probably of further importance in nutrient loading to, and cycling in, Onondaga Lake.     

Modifications in phosphorus loading to Onondaga Lake,U.S.A., Associated with alkali Manufacturing

The effects of an alkali production facility on P loading to the epilimnion of Onondaga Lake are documented for the spring to fall interval of 1980 and 1981. The effects include additional load to the epilimnion from the hypolimnion and the outlet, and reduced loads from dense, ion-enriched inflows. Despite the compensating effects, the load received by the epilimnion from spring through fall is greater than previously estimated as a result of the manufacturing operations.     

Distribution of mercury in the sediments of Onondaga Lake,N.Y.

Sediment cores and surface grab samples were collected throughout Onondaga Lake, New York, to determine the concentrations and distribution of mercury (Hg) in the sediments. Horizontal distribution patterns show the effect of sediment focusing and localized sources, with generally low Hg concentrations in the littoral zone sediments, higher concentrations in the profundal sediments, and highest concentrations near known sources of Hg. Several cores were dated and reflect historical loading patterns, with low-level increases in Hg concentration starting in the early 1800s and a large increase in 1947 and decrease in 1970 related to the local chloralkali industry. These cores indicate that Hg has low mobility in profundal sediments and that the contaminated sediments are effectively being buried.     

Failure of spring turnover in Onondaga Lake,NY, U.S.A.

Onondaga Lake, N.Y., failed to turnover in the spring of 1986 because of the strong chemical stratification under the ice that developed as a result of ionic discharges from an alkali plant. This stratification had a negative impact on the O₂ resources of the lake, as the lower depleted layers of the lake were not replenished with O₂. Anoxia and anaerobiesis in the bottom water expanded following ‘ice-out’. Comparison of characteristics observed for the winter through spring interval of 1986 with historic data indicates Onandaga Lake has failed to experience spring turnover in a number of years (approximately 7 of the last 18 yr) because of the ionic discharges from the alkali plant.     

A chloride budget for Onondaga Lake,New York,U.S.A.

A Cl budget is presented for a 12 yr period (1970–1981) for Cl enriched (approximate volume-weighted average concentration of 1500 mg Cl L^?1) Onondaga Lake, New York. The budget utilizes continuous discharge and lake and stream water chemistry data, collected at an interval of approximately 2 weeks, over the 12 yr study period. Budget calculations are supplemented by high frequency water chemistry data from the lake and the tributary carrying the major portion of the loading. More than 85% of the external load of Cl (approximately 9 × 10⁸ kg yr^?1) to the lake originates from an alkali manufacturer. Export of Cl from the lake was highly correlated to outflow from the lake (R = 0.915, for a resolution of 1 mo). A good balance between estimated external loads and lake export was obtained (within 7%) for the 12 yr period, indicating that lake concentrations are consistent with external loading of this conservative substance. The results of this analysis contradict previous calculations that indicated 40 to 50% of the Cl in the lake originated from natural internal sources.     

Dry Weight Deposition in Polluted Onondaga Lake,New York,U.S.A.

Short and long-term trends in dry weight deposition rates are documented for polluted Onondaga Lake, NY, based on analyses of sediment trap collections made below the epilimnion at a single deep-water location in ten years over the 1980–1992 period using cylindrical traps. Additionally, comparisons of dry weight rates obtained with two different diameter (4.0 and 7.6 cm) traps of the same aspect ratio (6), at four different depths below the epilimnion, and from the lake's two basins, in 1993, are presented to establish the representativeness of the long-term data. The near equivalence of fluxes determined with the different size traps and cumulative deposition rates measured over the range of deployment depths, and the minor differences in flux observed for the two basins, supports the representativeness of long-term data in quantifying deposition rates for the pelagic zone of the lake. Short-term variations in downward flux have been common in the lake over the period of monitoring. The summer-average dry weight deposition rate decreased systematically (by about 45%) following the closure (in 1986) of a soda ash facility that caused enhanced rates of calcium carbonate deposition; from an average of 23.2 to 12.8 g m-² d-¹. These dry weight deposition rates are high compared to values reported in the literature for other lakes, and are responsible for the lake's high rate of net sedimentation.     

Density stratification in ionically enriched Onondaga lake,U.S.A.

Denstity stratification was characterized in ionically enriched Onondaga Lake for a 7 mo period of 1980, based on paired profiles of temperature and cloride collected at 1 m depth intervals from a single deep water location on 54 different occasions. The lake was both thermally and chemically stratified. The chemical component represented 38.5% of the density stratification for the study period. It was most often the dominant component in establishing the depth of the upper mixed layer, which was unusually shallow in the lake. Further, the presense of the chemical component prolonged the stratification period. The chemical component of stratification decreased progressively through the study. The altered stratification characteristics of the lake may have negative effects on the level of biomass in the upper waters and the oxygen resources of the lower waters.     

Depletion of epilimnetic oxygen and accumulation of hydrogen sulfide in the hypolimnion of Onondaga Lake,NY, U.S.A.

The depletion of epilimnetic DO during fall, and the accumulation of H₂S in the hypolimnion during summer, are documented for polluted hypereutrophic Onondaga Lake, NY, U.S.A. The fall epilimnetic DO depletion is so severe that in many, if not all years, the New York State standard for minimum DO of 4 mg- L^?1 is violated for periods as long as 1 mo. The depletion is caused by the transport of O₂ demanding species, particularly H₂S, from the hypolimnion into the epilimnion. Hydrogen sulfide accumulates progressively through the summer, mostly via SO _inf4 ^sup2? reduction, to unusually high concentrations; a maximum of 1.65 mM has been observed. These conditions are apparently manifestations of hypereutrophy, and thus may be subject to remediation through P management efforts.     

Mercury cycling in the water column of a seasonally anoxic urban lake (Onondaga Lake,NY)

Onondaga Lake, New York, is a hypereutrophic, urban lake that was subjected to industrial discharges of mercury (Hg) between 1947 and 1988. Water samples were collected from April through November 1992 and analyzed for filtered and unfiltered total Hg, methylmercury (CH₃Hg), dimethylmercury, ionic Hg, and elemental Hg to characterize the biogeochemical cycling of Hg during water column stratification and hypolimnetic anoxia. In the spring and late fall when the water column was isothermal, total Hg and CH₃Hg concentrations were relatively constant throughout the water column, at approximately 3–7 ng/L and 0.3–1 ng/L, respectively. Through the summer and early fall, CH₃Hg concentrations systematically increased in the deeper waters, reaching peak concentration in August and September. In September 1992, CH₃Hg concentrations increased from 0.3 ng/L in the epilimnion to 10.6 ng/L in the hypolimnion, an increase of nearly 2 orders of magnitude. At the same time, total Hg increased from 6.6 ng/L in surface water to 21.7 ng/L at depth, a 3-fold increase. The spatial and temporal patterns observed for CH₃Hg agree well with manganese, suggesting that CH₃Hg and manganese are controlled by processes of the same or parallel cycles.     

Modeling Cl concentration in Cayuga Lake,U.S.A.

The annual average concentration of Cl in Cayuga Lake, NY, has decreased from a value of approximately 102 mg L^?1 in 1970, when the discharge of NaCl fines from an adjoining rock salt mine was discontinued, to a concentration of approximately 46 mg L^?1 in 1988. A complete-mixed model for Cl concentration accurately simulated this decrease in concentration, establishing that the decrease was the result of an abrupt reduction in loading. The time course of the decrease strongly supports the position that the high Cl concentrations that prevailed in the lake in the late 1960's were largely a result of the discharge from the mining facility, and not due to the input of enriched groundwater as previously hypothesized. The predicted steady-state Cl concentration associated with the complete flushing of the mining facility input, expected in about the year 2000, is approximately 32 mg L^?1. Further, the model analysis supports previous speculation that the major source of material loading to the lake, the Seneca River, ‘short-circuits’ to the outlet; i.e., this tributary should not be included in material budgets for the lake.     

Sediment Quality in Burlington Harbor,Lake Champlain,U.S.A.

Surface samples and cores were collected in 1993 fromthe Burlington Harbor region of Lake Champlain. Sediment samples were analyzed for trace metals(cadmium, copper, lead, nickel, silver and zinc),simultaneously extracted metal/acid volatile sulfide(SEM-AVS), grain size, nutrients (carbon and nitrogen)and organic contaminants (polycyclic aromatichydrocarbons (PAHs) and polychlorinated biphenyls(PCBs)). The concentrations of cadmium, copper,silver and zinc from the partial sediment digestion ofthe surface samples correlated well with each other(r ²>0.60) indicating that either a commonprocess, or group of processes determined the sedimentconcentrations of these metals. In an analysis of thespatial distribution of the trace metals and PAHs,high surficial concentrations were present in thesouthern portion of the Harbor. The trace metal trendwas strengthened when the concentrations werenormalized by grain size. A sewage treatment plantoutfall discharge was present in the southeasternportion of the Harbor at the time of this study and isthe major source of trace metal and PAH contamination. Evaluation of sediment cores provides a proxy recordof historical trace metal and organic inputs. Thepeak accumulation rate for copper, cadmium, lead, andzinc was in the late 1960s and the peak silveraccumulation rate was later. The greatestaccumulation of trace metals occurred in the late1960s after discharges from the STP began. Subsequentdeclines in trace metal concentrations may beattributed to increased water and air regulations. The potential toxicity of trace metals and organiccontaminants was predicted by comparing contaminantconcentrations to benchmark concentrations andpotential trace metal bioavailability was predictedwith SEM-AVS results. Surface sample results indicate lead,silver, ΣPAHs and ΣPCBs are potentially toxicand/or bioavailable. These predictions were supportedby studies of biota in the Burlington Harborwatershed. There is a clear trend of decreasing PAHand trace metal contaminant concentrations withdistance from the STP outfall.     

Chloride cycling in two forested lake watersheds in the west-central adirondack mountains,New York,U.S.A.

The chemistry of precipitation, throughfall, soil water, ground water, and surface water was evaluated in two forested lake-watersheds over a 4-yr period to assess factors controlling Cl^? cycling. Results indicate that Cl^? cycling in these watersheds is more complex than the generally held view of the rapid transport of atmospherically derived Cl^? through the excosystem. The annual throughfall Cl^? flux for individual species in the northern hardwood forest was 2 to 5 times that of precipitation (56 eq ha^?1), whereas the Na⁺ throughfall flux, in general, was similar to the precipitation flux. Concentrations of soil-water Cl^? sampled from ceramic tension lysimeters at 20 cm below land surface generally exceeded the Na⁺ concentrations and averaged 31 μeq L^?1, the highest of any waters sampled in the watersheds, except throughfall under red spruce which averaged 34 μeq L^?1. Chloride was concentrated prior to storms and mobilized rapidly during storms as suggested by increases in streamwater Cl^? concentrations with increasing flow. Major sources of Cl^? in both watersheds are the forest floor and hornblende weathering in the soils and till. In the Panther Lake watershed, which contains mainly thick deposits of till (>3 m), hornblende weathering results in a net Cl^? flux 3 times greater than that in the Woods Lake watershed, which contains mainly thin deposits of till. The estimated accumulation rate of Cl^? in the biomass of the two watersheds was comparable to the precipitation Cl^? flux.     

Metal concentrations in the ground water of the Ouachita Mountains,Arkansas, U.S.A.

Ninety-one ground water samples (predominantly from springs) in two mineralized areas of the Ouachita Mountains in west-central Arkansas, were analyzed for Fe, Mn, Zn, Cu, Co, Ni, Pb, Hg, Sb, Sr, Ba, Ca, and Li. These areas contain Mn, barite, strontianite, cinnabar, stibnite and scattered Pb-Zn mineralization, Cumulative frequency curves were used to determine the threshold and anomalous concentrations for each element in the two areas. These values were, in general, higher in the ground water from the more mineralized area for several of the base metals, but most notably for Mn and Fe, the principal metals in the Mn oxide minerals. The United States Environmental Protection Agency (EPA, 1976) criteria for Fe (300 μg L ^?1) and Mn (50 μg L^?1) in drinking water were exceeded, respectively, in 34% and 30% of the springs in Area I, and 13% and 23% in Area II. One spring exceeded the EPA Hg criterion (2 μg L^?1) and 3 springs exceeded the 50 μg L^?1 criterion for Pb. In spite of the large number of anomalous Ba concentrations, the highest concentration of Ba was 930 μg L^?1 (EPA criterion 1000 μg L ^?1).     

Onondaga Lake and the dynamics of chloride in the Oswego River

The temporal distribution of chloride concentration in the Oswego River was determined at 6 hr intervals for a 3 mo period during the summer of 1982. The dynamics of relative flow and chloride contributions from the three major sources forming the Oswego River, and the dynamics of flow releases from one of the sources, chloride-polluted Onondaga Lake, were determined from the above measurements, available chloride concentrations, and flow data for the system, through application of a simple mass balance on chloride. The chloride concentration and load in the Oswego River were found to be highly variable with time, and largely due to the dynamics of flow release from Onondaga Lake. The chloride distribution in the Oswego River, with its unique dynamics and chemically conservative nature, make it a valuable hydraulic tracer for the system.     

Responses of Nutrients to Experimental Acidification and Recovery in Little Rock Lake,U.S.A.

Nutrient concentrations and cycling processes were studied in Little Rock Lake, Wisconsin, U.S.A., during experimental acidification from pH 6.1 to target pH values of 5.6, 5.1 and 4.7 and during the first four years of recovery. Surface waterconcentrations of ammonium, nitrate, soluble reactive phosphate,and total phosphate were not affected, but total nitrogen was lower from year 2 at pH 5.6 until the end of recovery year 3 (pH 5.3). The decrease was attributed to lower dissolved organicN. Annual maximum concentrations of N and P forms at 9 m depth in the hypolimnion increased with decreasing pH, but most of theincrease resulted from a drought-induced decline in lake levelduring acidification that brought the 9 m sampling location closer to the sediment. In contrast to findings elsewhere, acidification of Little Rock Lake had no effect on rates of nitrification during winter ice-cover. Dissolved silica concentrations increased slightly at pH 4.7, probably because of a pH-induced decrease in the diatom population, but hydrologicfactors were more important in controlling silica levels than waspH. Most of the predictive hypotheses made about the effects ofacidification on nutrient forms and processes or their recoveryin the lake were qualitatively correct.     

Changes in water content in and under frozen soil in Iowa,U.S.A.

Water contents were measured in a soil profile during the winter from the time of harvest until soil temperatures were greater than 0°C through this profile in the spring. Water movement between successive layers was predicted using the Darcy flow law and changes in water flux. These values were then compared with the changes in soil water content observed in field measurements. Results showed that water content changes (accumulation or loss) below the frozen layer were greater than predicted but that the differences between predicted and measured contents were small, much smaller than the amounts reported in previous experiments.     

Salinity,chloride, and density relationships in ion enriched Onondaga Lake,NY

The relationship between salinity (S), chlorinity (Cl) and density (d) for the ion polluted (S = 3 to 4.5‰) and stratified Onondaga Lake are presented. The data base includes 220 determinations of the major ionic components collected from ten equally spaced depths. The salinity (S) and ionic strength (I) in the lake can be estimated from S = 1.85 Cl ? 0.28, where Cl is in g kg^?1 and I = 1.456 [Cl^?] ? 0.039, where [Cl] is in mmol L^?1. Due to the high concentration of Ca²⁺ in the lake, the seawater equation of state (Chen and Millero, 1977a) could not be used to estimate reliable densities for the lake (Δd ～ 100 × 10^?6 g cm^?3). A reliable equation of state for Onondaga Lake was derived from the composition data $$d = d_0 + A_v {\text{ }}CL + B_v {\text{ }}Cl^{3/2} $$ where d ₀ is the density of water (g cm^?3), A _v is a temperature dependent parameter related to the infinite dilution apparent molal volumes and B _v is related to the ion-ion interactions of the lake salts. The high ionic content of the lake depresses the temperature of maximum density to 3.18°C and alters the stratification of the lake. The salinity component of the stratification represents 40% of the total density stratification.     

Scientific principles for water utilization in the U.S.S.R.

Water resources are essential for economic and cultural development of a territory. Both economic development and the health of the people depend on the provision of pure water. Scientifically founded plans of water resources use and conservation should be based on a balance approach to the assessment of available water supply sources and, on the forecast of their interconnected change in the future in a close association with the forecast of the whole economy and culture of the studied region. In the future the main threat to the normal development of the economy and life will not be water deficiency but the conversion of rivers, lakes and other water supply sources into sewers. Therefore it is proposed that there be a complete cessation of sewage discharge (even of the so-called purified) into water supply sources while drawing up long-term water management balances.