Elements of Carbon Balance in Oligotrophic Bogs

Elements of carbon balance of oligotrophic bogs were studied using an example of the landscape profile of the Klyuch River in 1998–2000. Carbon balance was preliminarily calculated taking into account the biological productivity, release of carbon dioxide and methane, and carbon outflow with bog waters. Based on the data obtained on the carbon inflow and outflow, the conclusion was made concerning the progressive peat formation in the region studied.     

Exploratory study of suspended sediment concentrations downstream of harvested peat bogs

Peat bog harvesting is an important industry in many countries, including Canada. To harvest peat, bogs are drained and drainage water is evacuated towards neighboring rivers, estuaries or coastal waters. High suspended sediment concentrations (SSC) were found in the drainage water at one particular site during the 2001–2002 spring seasons in New Brunswick (Canada). The main objective of this study was to verify this observation at other sites, compare SSC levels leaving harvested peat bogs with those leaving an unharvested bog, and to determine if high SSC events happen only in Spring or all year round. Suspended sediment concentrations were monitored downstream of three harvested peat bogs and an unharvested reference bog located in New Brunswick during the ice free seasons of 2003–2004. On average, SSC at the harvested sites exceeded 25 mg/l, which is the recommended daily maximum concentration, 72% of the time, while the same concentration was exceeded 30% of the time at the unharvested sites. SSC were found to be significantly higher at harvested sites than at the reference sites for all seasons. The highest SSC medians were recorded in the Fall but SSC was elevated in all seasons. High SSC levels in receiving waters may be caused by field ditching activities and insufficient sediment controls. Findings suggest the NB Peat Harvesting 25 mg/l SSC guideline should be reviewed.     

Behavior of 137Cs in soils of transitional bogs

Specific features of ¹³⁷Cs accumulation, transformation, and migration in humus-peaty and peaty-gley soils of transitional bogs are discussed with reference to the southwestern part of the Russian Federation, which was most heavily contaminated after the Chernobyl accident. The influence of physicochemical soil properties and concentrations of typomorphic elements on these processes is characterized. It is concluded that bog soils accumulate ¹³⁷Cs in the form of hardly movable compounds and, as a consequence, transitional bogs are transformed into critical ecosystems.     

A PRELIMINARY STUDY OF THE EFFECTS OF DRAINAGE AND HARVESTING ON WATER QUALITY IN OMBROTROPHIC BOGS NEAR SEPT-ILES,QUEBEC1

ABSTRACT: Runoff and ground-water samples were collected from four ombrotrophic bogs, representing undisturbed and drained/harvested conditions, at two-week intervals during the summer of 1984. Analyses of samples for water quality parameters revealed significant (P < 0.05 level) increases in specific conductance, NH4⁺-N, total dissolved P, Mg, K, and Na and a decrease in the E₄:E₆ ratio (suggesting increased proportions of humic acid) associated with drainage. There were no significant changes in dissolved organic carbon, Ca concentrations, or pH. Comparison of samples collected before, during, and after ditching showed increases in the dissolved organic carbon, NH₄⁺-N, total dissolved P, K, and Na and a decrease in the E₄:E₆ ratio, but these changes were short lived; water quality returned to preditching values after about a week. The observed changes in water quality are small, probably because the peat is very acid (pH 3.0 to 4.5).     

Selecting indicator species to monitor ecological integrity: a review

We review critical issues that must be considered when selectingindicator species for a monitoring program that aims to maintainor restore ecological integrity. First, we examine the pros andcons of different management approaches on which a conservationprogram can be based and conclude that ecosystem management ismost appropriate. We then identify potential indicators ofecological integrity at various levels of the ecosystem, with aparticular emphasis on the species level. We conclude that,although the use of indicator species remains contentious, it canbe useful if (1) many species representing various taxa and lifehistories are included in the monitoring program, (2) theirselection is primarily based on a sound quantitative databasefrom the focal region, and (3) caution is applied wheninterpreting their population trends to distinguish actualsignals from variations that may be unrelated to thedeterioration of ecological integrity. Finally, we present anddiscuss different methods that have been used to select indicatorspecies.     

Aggregated Estimation of the Basic Parameters of Biological Production and the Carbon Budget of Russian Terrestrial Ecosystems: 1. Stocks of Plant Organic Mass

The data presented were obtained at the first stage (1993–1999) of studies on evaluating the basic parameters of biological production in Russian terrestrial ecosystems in order to provide information for assessing and modeling the carbon budget of the entire terrestrial biota of the country. Stocks of phytomass (by fractions), coarse woody debris, and dead roots (underground necromass) were calculated by two independent methods, which yielded close results. The total amount of phytomass in Russian terrestrial ecosystems was estimated at 81800 Tg (=10¹² g = million t) dry matter, or 39989 Tg carbon. Forest ecosystems comprise a greater part (82.1%) of live plant organic matter (here and below, comparisons are made with respect to the carbon content); natural grasslands and brushwoods account for 8.8%; the phytomass of wetlands (bogs and swamps), for 6.6%; and the phytomass of farmlands, for only 2.5%. Aboveground wood contains approximately two-thirds of the plant carbon (63.8%), and green parts contain 9.9%. For all classes of ecosystems, the proportion of underground phytomass averages 26.7% of the total amount, varying from 22.0% in forests to 57.1% in grasslands and brushwoods. The average phytomass density on lands covered with vegetation (1629.9 million hectares in Russia) is 5.02 kg/m² dry matter, or 2.45 kg C/m². The total amount of carbon in coarse woody debris is 4955 Tg C, and 9180 Tg C are in the underground necromass. In total, the vegetation of Russian terrestrial ecosystems (without litter) contains 54124 Tg carbon.