Morphological/anatomical investigation of cattail transplants and bog vegetation : final report

Bogs and coal acid mine drainage are closely linked at the \nVictoria Junction Coal processing plant of DEVCO in Sydney, Cape \nBreton, Nova Scotia. This geographical setting facilitates the \ninvestigation of these bogs with respect to the effects of AMD on \nthe ecosystem and determine their use in ameliorating the acidic \nconditions. The species assemblage is typical of that encountered \nin dwarf-shrub bogs of the Northeastern regions of the United \nStates and Canada. These bogs are dominated by Chamaedaphne \ncalyculata. \nThis report describes the status of the vegetation in both bogs \nwhich have received AMD for varying times. It summarizes both onsite \nand laboratory investigations. Through the use of \nmorphological-anatomical techniques, the death or growth of plant \nparts is determined. The old bog, exhibits significant acid stress, although it had only \nreceived aerial deposition of coal and a diffuse flow of AMD. A \nsecond bog, the new bog, located immediately above the stressed bog \nwas healthy and unaffected by acid mine drainage until AMD seepage \nwas diverted into the bog at the end of summer 1988. In the new bog \nthe vegetation damage is much more severe than in the old bog and \nprognosis for continued survival is not good for many of the \nspecies that form the natural species assemblage of the bogs. The majority of shoot tips and lateral buds were found to be dead, \nsuggesting little hope for recovery of the plants in subsequent \nyears. Although damage was also observed in the same species of the \nold bog, the symptoms were not as severe as those seen in the new \nbog. Roots and rhizomes tended to show some damage but this was \nmuch reduced in comparison to that observed in the new bog. The most important species being able to survive is Typha \nlatifolia. Other grasses, sedges, and rushes may however compete \nin the colonizing of the dying bogs. Thus, a change in species \ncomposition of the bogs can be expected. To promote the growth of \ncattails in AMD conditions foliar fertilizers were tested. \nTreatment with noticeable beneficial effects was the application \nof 4-18-16 at a dilution of 1O:l. \nMorphological investigations of cattail roots indicated large \naccumulation of metals on the epidermis and the hypodermal layers. \nIn dead lateral roots, metal concentrations are highest and have \npenetrated the entire root cross section. Analysis of X-ray spectra \nof the metals by SEM of root cross sections, indicated that high \nconcentrations of Fe are associated with high levels of S and \ngreatly reduced concentrations of Ca. Crystal formation was noted \nin the iron-sulphate plaque accumulation in the roots. X-ray scans \nof cattail leaves growing in AMD conditions indicate the presence of glandular cell regions, called hyropoten with Fe levels three \ntimes that of the adjacent epidermal regions. These findings \nsuggest, that the cattail rhizosphere may be active in ameliorating \nAMD and that adaptations to high iron concentrations through \nactivation of particular cell regions of the leaves may occur.

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