Turkey Lakes Watershed Study reference list: 1984

Report presents a data summary of daily water flows measured at six NWRI stream gauging stations in TLW. Plots of corresponding meteorological conditions and hydrographs are also included. High unit discharges or runoff ranging from 731 to 1221 mm yr^-1 were determined which leads to relatively short water renewal times for the lakes (from 0.15 yr for Wishart L. to 1.3 yr for Batchawana N.)

This report discusses the relationship between the enzyme activity of arylsulphatose in lake sediments with 1) the pH of the overlaying waters and 2) sediment metal concentrations. Data on chemical characteristics and enzyme activity of sediments for several lakes are presented including Turkey Lake which is considered to be the "remote and fairly pristine" member of the lake set.

Sedimentation rates were determined for 14 Ontario lakes including Batchawana (identified as upper headwater in the report: which basin not clear), Little Turkey, and Turkey Lakes in the TLW. Both ²¹⁰Pb and ¹³⁷Cs techniques were used to establish the sedimentation rates which ranged from 0.67 (Turkey L.) to 0.96 mm yr^-1 (Batchawana L.). A detailed description of the radiometric dating technique (calculations) is given.

Report presents results of an examination of the benthic fauna in each lake of the TLW. Although there was a slight reduction in the number of taxa present in the lake of lowest pH (e.g. Batchawana L.), there was little overall relation between fauna abundance or biomass and lake pH or alkalinity. High littoral biomass in Batchawana L. is related to a lack of fish predation.

The report discusses the factors governing the spatial and temporal variations in ionic content of surface water in the TLW. Geological and hydrological factors are most important. High elevation streams where till thickness is minimum have lower pH, calcium, and alkalinity, and sulphate is the dominant anion. At low elevation where overburden thickness is greater, generally higher ionic concentrations occur, and alkalinity is the dominant anion. The high elevation waters experience the greatest temporal changes in concentration; these are often related to flow, particularly the hydrologic peaks associated with spring melt.

The carbon uptake rate of phytoplankton was observed to increase from the poorly buffered headwater lake to the better buffered lakes downstream. Water pH, alkalinity, and dissolved inorganic carbon also increased in a parallel fashion and the report discusses the relationships among these observations. In particular, a hydrological model predicts that a greater groundwater component is present in the downstream waters and this can account for the above observations.

Report presents the development and preliminary application of a hydrological model in which the different hydrological components of the model are arranged so that they may be related easily to other physical and chemical processes. The model assumptions are discussed also. It is shown to successfully reconstruct the hydrograph for several of the TLW sub-basins using meteorological data as the essential input.

Hydrological model results show progressively increasing groundwater discharges on the stream pathways of the TLW. The results explain the observed spatial gradients of ANC, pH, Ca²⁺ and Mg²⁺. A general approach to interfacing hydrological and chemical interaction models is discussed.

Text (with figures) of presentation given at the Royal Society Review of the federal LRTAP research program. Fossil diatoms were used to infer the pH history of lakes in TLW. Results were variable from lake to lake, even basin to basin within a lake. Trends in inferred pH were to lower values in more recent times in most cases. The preliminary nature of the interpretation was stressed.

This report provides a brief literature review covering the last decade on acid deposition and its possible influence on forest health and productivity. Topics covered include measuring forest growth, "artificial rain" experiments, tree crown leaching, soil biota and biological processes, soil acidification, base leaching and metal mobilization.

This report presents a comprehensive review of the literature (pre-1983) dealing with the effects of acid deposition on forest ecosystems. All aspects noted in 84-10 above are covered as sell as discussion of sulphur and nitrogen cycles, site susceptibility, and disease and insect attack. Relationship of all of these factors to forest productivity is considered.

Soil properties and ion fluxes measured in TLW were used to determine whether acid deposition could lead to base leaching from the vegetation and soil. Base cation leaching was associated with organic acids, sulphate, nitrate, and bicarbonate depending on horizon. The large exchangeable base cation pool present in the soils suggests that it is unlikely that significant leaching will occur at present desposition levels.

The influence of acid deposition on the ionic composition of throughfall, forest floor percolate, and mineral soil solution was studied. Rainfall acidity was reduced 50% on passage through the canopy, and subsequently, almost all of the remainder was consumed on entry into the mineral soil horizons.

Major ion concentrations, pH and conductivity were measured in precipitation and headwater streams during 1981 in TLW. Precipitation and stream loading rates were calculated, and causes of temporal and spatial variability discussed. Bicarbonate was the most important anion countering cation losses from low elevation, deep soils, while sulphate was more important for high elevation, thin soils.

Report presents development for and application of a watershed acidification model to the Batchawana Lake Basin (see 83-12). The rate of acidification of surface waters is primarily dependent on soil infiltration-percolation rates, soil depth, and soil ANC. A method for estimating long term acidification is proposed.

Information is presented on observed symptoms and responses of fish communities in low pH lakes of Ontario. Topics covered include: community and population changes, changes in abundance, cases of lakes in terminal stage of fish loss, species tolerance, mixed community and recruitment failure, and contaminant levels in fish. Emphasis is placed on presentation of new material.

Report summarizes daily air concentrations and wet-only precipitation data for stations in the APN for the 1982 calender year. TLW data are found in Appendix 2 (labelled "Algoma").

As in CWS reports I and II, (82-16 and 83-26), lakes in the Ranger Lake area (near the TLW in Algoma) were sampled as part of a study on the effects of acid precipitation on waterfowl. In this report the age structure and condition indices of minnow species is summarized and the correlation with environmental variables is considered. The occurrence of most species seems unrelated to chemical parameters. Controlled laboratory experiments are recommended because of the high number of variables affecting growth rates and pH/metal effects on fish.