Acidic Bog Research Articles

Ecological Significance of Four Critical Elements in Plants of Raised Spagnum Peat Bogs

The concentrations of N, P, Mn, and Al in plants of two ombrotrophic bogs and four adjacent environments were examined. The current year's foliage of the evergreen bog species, as contrasted with the older leaves, invariably possessed higher concentrations of N and P and lower concentrations of Al and Mn. Within the bog species, the composition of the current year's foilage of the evergreens was not significantly different for any of the elements from that of the deciduous species. Foliage of the bog species was lower in content of N and P than the foliage of plants of other habitats and reflects the paucity of available N and P in the bog substrate. Broad—leaved evergreen leaves of bog plants appear to manufacture more photosynthate per acquired unit of N or P than do deciduous leaves, primarily because of their longevity. The high occurrence of evergreenness in infertile environments may therefore reflect a decreased need to acquire N and P from a substrate deficient in these elements. Mn and Al contents were comparable in the bog plants to plants of other habitats, despite potentially toxic levels of these elements in acid bogs. Apparently many bogs plants selectively exclude Mn and Al.

POLLEN DIAGRAMS FROM THE NORTH YORK MOORS

SummaryFour pollen diagrams from the Egton High Moor watershed of the North York Moors are described. Two are from infilled sub‐glacial meltwater channels and two from blanket peat. The channel mires developed from woodland through fen peats (dominated by Thelypteris) to acidic bogs during Post‐glacial times. The uplands started to accumulate peats in late zone VI or early zone VIIa. The stratigraphy suggests that fire as well as paludification was involved in the inception of blanket peat. Clearance phenomena are observed in pre‐Ulmus decline times and some of these are tentatively assigned to Mesolithic activity. In the upper portions of the diagrams massive forest clearance is seen and this is probably due to Bronze Age occupation. The representation of Tilia is discussed in its regional context and the possible significance of the Fagus percentages in the light of Tauber's work is briefly mentioned.

Peat Deposits of Scar Close, Ingleborough, Yorkshire

The interest of the area known as Scar Close, Yorkshire, is evident from the number and variety of investigations which it has provoked. Jones (1965) has considered its geological aspects, Parry (1960) and Sweeting (1966) its geomorphology, and Moisley (1954) emphasized the need for further study in his account of karstic features of similar sites in the Malham area. This paper is the result of an attempt to add to the substantial body of knowledge from a botanical angle using amongst others the technique of pollen analysis. Scar Close (Grid Ref. SD 750773) is situated at the foot of the north-west side of Park Fell near the steep face of Ingleborough in the Craven district of Yorkshire. It lies on a shelf of Great Scar Limestone at a height of about 1000 ft (305 m). The fell is composed of rocks of the Yoredale Series and the boundary of these with the limestone is marked by a row of swallow holes. The limestone itself has formed pavement with well-developed clints and grykes. The rainfall is high with an annual average of about 70 in. (180 cm), but most of it drains down through the grykes and swallow holes into an underground system. Drainage is impeded to some extent on the inner side of the shelf by a layer of glacial drift, and even on the clints which are practically devoid of soil, some surface water is retained in solution hollows. The drift covered area carries a more or less continuous sheet of wet acid bog, but on the exposed pavement there are only isolated patches of peat lying in direct contact with the limestone and it is these 'islands' which are problematic. They may be relics of a once continuous peat cover or have developed independently from a number of centres and still be advancing. In any case it is unusual to find peat situated immediately upon a well-drained basic substratum. The vegetation of the inner and outer areas of the shelf reflects the difference in edaphic conditions (Fig. 1). The drift-covered limestone bears a typical hummock and pool formation with Eriophorum angustifolium,* E. vaginatum, Vaccinium myrtillus, Calluna vulgaris and various Sphagnum species on the hummocks, and a luxuriant growth of S. cuspidatum in the pools. The peat 'islands' on the pavement are much drier and are dominated by Calluna vulgaris and Vaccinium myrtillus with other species such as Convallaria majalis, Geranium sanguineum and Polypodium vulgare. Most of the peat patches are fringed with mosses including Rhytidiadelphus squarrosus, Pleurozium schreberi and Cratoneuron commutatum. Where small pockets of soil have developed on the clints Sieglingia decumbens and Tortella tortuosa have become established, but they are mostly bare except for crustaceous lichens. A few trees of Acer pseudoplatanus, and Fraxinus excelsior are growing in the grykes with bushes of Corylus avellana, but all are comparatively small and rarely exceed 4 m in height. Other plants found in the grykes are * Nomenclature follows Clapham, Tutin & Warburg (1962) for vascular plants and Richards &

Grauballemandens sidste Måltid

Grauballemandens sidste Måltid

Lake Water and Sediment

Dried and reconstituted mud from pairs of primitive, medium, productive, and acid bog lakes was shaken to phosphorus equilibrium with water. Minimal P was released at pH 5.5–6.5, and ranged from scarcely above the level of chemical detection up to 0.2 ppm in productive lakes. Further acidity caused a slight increase of P in the water, up to 0.3 ppm, and alkalinity a larger increase, up to 0.5 ppm. At all pH levels the quantity released increased in the order of lake types stated above. The pH versus P curve for whole mud was shallow or saucer‐shaped; ashed mud gave a similar but deeper or cup‐shaped curve. Thus a productive lake ash at pH 4 released 1.0 ppm and at pH 8, 1.2 ppm. When 1 ppm of P was added to the water prior to the shaking, the lake type reacted differently. Acid bog and productive lake muds left the added P in the water, while unproductive lake muds removed most of it under acid conditions but not at pH 7 or more. The adsorption behavior of ash is similar to that of Bentonite, Fuller’s earth, or ferric hydroxide gel.

Lake Water and Sediment

Sixteen lakes are described, varying in geology and all but two of low productivity, and including three acid bog types. A method is described for indirect estimation of the sum of Na and K. In lakes generally, low pH is related to low conductivity, but in these coastal lakes the Na in ocean spray keeps up the conductivity even in very acid waters. At equilibrium the inorganic P in solution is 2–3 ppb and represents a residual soluble fraction, independent of productivity and pH. Total P is 10–15 ppb and the concentration is not related to productivity. There is an annual cycle of inorganic P with a winter maximum, spring decline, and summer minimum. Methyl orange alkalinity varies directly with the sum of Ca and Mg and with either of the ions separately. The scatter in the regression of alkalinity versus Mg is greater than that of alkalinity versus Ca. There is a reduction of per cent organic material in the sediments directly related to increasing alkalinity. The cause is attributed to greater bacterial activity as the pH goes up.

Lake Water and Sediment1

Redox potentials of mud cores from seven lakes, including acid bog, unproductive, and productive types, were measured with Mortimer’s multiple electrode. A break existed below the surface, but variation in measurement was too great to characterize its depth within ±30–50%. Accuracy of potential measurement is limited by lack of poise, so that the scatter of units of the multiple electrode increases as a standard solution or a natural mud is diluted with distilled water. With the muds studied the scatter was ±50 mv. In poorly poised systems the area of platinum is also important, so that potentials of 0.01 to 0.42 volts were obtained on the same sample with electrodes of different sizes. The presence of H2S causes a voltage drop, e.g., 20‐min. bubbling of a reduced solution with H2S caused the voltage to fall from 0.63 to 0.17 v. Production of H2S in nature is abolishedby O2. As a further difficulty the sediments of some lakes are able to deposit a sulphide plating on submerged platinum. Evidence is presented that the real oxidized layer is one mm or less thick, and that the reported break in the electrode curve at about one cm is caused by factors other than oxidation of iron salts, e.g., turbulent stirring of the sediment by wind‐induced currents, and presence of sulphide.

The Development of Peat Lands

great scientific as well as practical interest. Reclamation of such land, and use of the peat itself, is a matter of importance throughout northern Europe, and for this reason, if no other, it is highly desirable to know something of the processes involved in peat accumulation, and of the factors controlling it. Since the study of peat lands entails dealing with a mass of complex relations between organisms and their environments, our understanding of them is necessarily fragmentary and far from complete. Nevertheless, if a brief outline is presented of one type of vegetation and soil sequence which occurs in many parts of northern Britain, the scene may be set for a consideration of the way in which variations in the major environmental factors-climate, geology, relief, and organisms-can modify this type of succession over long periods of time, in different parts of the world. First, however, it

The Effects of Lime Application to Acid Bog Lakes in Northern Michigan

To investigate the observed correlation between alkalinity and productivity of lake waters and to test the use of lime in bog lakes to increase biological productivity, lime application was made to two, acid, soft-water, colored bog lakes in the upper peninsula of Michigan. Lime application was made twice to each of the two lakes, once in the summer under thermally stratified conditions and once in the autumn under nearly homothermous conditions, by pumping a lime-water mixture into the surface waters. Total rate of lime application was 100 pounds per acre-foot in each lake. The summer lime applications resulted in raising the pH and increasing alkalinity, total hardness and conductivity in the epilimnion only. The autumn application resulted in similar effects in the lower hypolimnion, because of sinking of the denser lime solution to the bottom where because of its greater density it did not later mix with upper layers. Lime application did not decrease the organic colloidal color. Total phosphorus was greatly increased in the bottom waters of one treated lake which originally was low in total phosphorus but there was no significant increase in the bottom waters of the other treated lake where total phosphorus concentrations were originally high. Total phosphorus also increased temporarily in the epilimnion of one lake following the summer application. A bloom of nannoplankton (Microcystis aeruginosa) was observed in one lake following the release of epilimnial phosphorus. Chemical data indicated that because of the presence of higher bicarbonate concentrations, the nannoplankton utilized carbon dioxide at a rate which may not have been possible without lime application. In both lakes the following summer, significantly higher standing crops of net phytoplankton were observed (principally of Dinobryon sertularia). Increases in standing crop of zooplankton also occurred the year following lime application.

FOREST COMMUNITIES IN NORTHWESTERN ALBERTA

Spruce, tamarack (larch), balsam fir, pine, and poplar communities of the region are described in terms of floristic composition and ecological relationships. The white spruce (Picea glauca) association is regarded as the climax type of the region. Of four phases or faciations presented by the white spruce association, the feather moss faciation appears to be the climax to which the other faciations tend to develop. Two black spruce (Picea mariana) communities are recognized, the black spruce – feather moss association and the black spruce–peat moss association. Of these, the former is characterized by "feather mosses" such as Hylocomium splendens and has developed on relatively level terrain without much peat formation, whereas the latter has a Sphagnum floor and has arisen in definite depressions through acid bog stages with the production of considerable peat. The black spruce – bog moss community is interpreted as subclimax, with natural succession to the black spruce – feather moss association. The tamarack (Larix laricina) community has many features in common with the black spruce – peat moss association but differs markedly, not only in its dominant species, but because of its development from a Drepano-cladus–Carex–Betula bog under persisting wet conditions. Succession to black spruce commonly occurs. Balsam fir (Abies balsamea) is relatively rare in the region and usually grows in mixed stands with white spruce, paper birch, aspen, and balsam poplar. Two divisions of the pine association are recognized, the jack pine (Pinus banksiana) and the lodgepole pine (P. contorta var. latifolia) consociations. For each of these, two phases are described, the pine – feather moss faciation on the more shaded sites and the pine–heath faciation on the more open and drier areas. Knowledge of the ranges of these two pines in northern Alberta and concerning hybrids between the species is extended. The poplar association, classified as aspen (Populus tremuloides) and balsam poplar (P. balsamifera) consociations, is considered in relation to other vegetation, especially prairie grassland and white spruce. Encroachment of aspen poplar upon native grassland is counteracted by various factors, notably burning. Natural succession of poplar and pine to white spruce is impeded chiefly by forest fires. Some attention is given to phytogeographical problems of this transition region.

Notes on Buxbaumia

Of interest to all bryologists who have made its acquaintance, Buxbaumia aphylla is perhaps one of the most unusual mosses. Those familiar with this species will recall that the only conspicuous part of it is the sporophyte. Most reports concerning the finding of this moss have indicated that generally the sporophytes occur in small numbers in any one particular location, although its distribution is widespread throughout the northern United States. In the Phoenix Bog area north of Syracuse, N.Y., however, along a sandy ridge between two acid bogs, there have been found recently at least six spots where Buxbaumia is growing profusely and many more locations where scattered capsules have been found.

EXCHANGE OF MATERIALS IN A LAKE AS STUDIED BY THE ADDITION OF RADIOACTIVE PHOSPHORUS

On July 1, 1948, 100 millicuries of radioactive phosphorus, P32, was added to the surface of an acid bog lake of area 0.3 hectares (0.8 ac.) and depth 6 m., situated near Halifax, Nova Scotia. The lake had a well developed⁁ zone of cold, stagnant water at the bottom with a thermocline above. Within a few hours the P32 was taken up strongly by the sphagnum (which made up most of the lake margin), by the floating plankton, and by sponges. Within a few days it had reached the bodies of fishes (Fundulus and Notemigonus), and within a fortnight had accumulated in their skeletons and viscera. No appreciable uptake of P32 by such bottom rooted forms as the cranberry (Vaccinium) and leather leaf (Chamaedaphne) was observed for more than two weeks. Penetration of added phosphorus into the lake depths was very slow, and even at the end of eight weeks the material was only doubtfully detected at the bottom. There was no evidence of active uptake by bottom mud. The ratios of maximum count per wet weight of organism to maximum count for the same quantity of lake water were as follows:Zooplankton 40,000Fundulus 13,000Sponge 4500Sphagnum 400Vaccinium 300Blue-green alga 300Chamaedaphne 100Nuphar 80

Certain Sociological Aspects Associated with Plant Competition between Native and Foreign Species in a Saline Area

Plant sociology has exercised a strong influence on the science of ecology and workers are constantly on the alert for new problems which may throw additional light on the subject. A desirable field which offers such an opportunity is the study of the sociological relationships of the foreign and native species to each other in America. Among the many inviting and favorable geographic regions in the United States for such a study, New York State is quite outstanding because of the nature of its topography and soils. The soils ranging from the saline seashores to the extremely acid bogs of the Adirondack Mountains are quite heterogeneous in their physical and chemical composition and offer in certain localities desirable habitats for the growth of foreign plant invaders. This condition together with the ease with which foreign plants entered the state through foreign shipments before quarantine laws were enacted now reveals cosmopolitan plant communities well stabilized in both natural and cultural habitats. In addition to these, denuded areas are constantly occurring by the excavation of large areas for road building materials, waterways and manufactured products as well as associated fills and residue dumps. These new physiographic areas where the soils are raw and sometimes rich in certain residue salts are highly desirable for the study of certain sociological relationships of native and foreign plants as to successional behavior under unusual environmental conditions. A new physiographic area located along the southwest shore of Onondaga Lake at the terminus of the old Erie Canal, which borders the City of Syracuse, N. Y., is similar to a condition mentioned above and forms the nucleus of the present investigation. This area, approximately one-quarter of a mile wide and one mile long, is a saline residue dump or fill about 12 feet high, deposited 34 years ago by a chemical manufacturing company. The soil is a finely ground limestone which was chemically treated and is therefore rich in salts, the principal ones being calcium carbonate, calcium chloride, sodium carbonate, sodium chloride, and potassium sulfate. Salt incrustations still occur in a few small areas slightly lower than the general surface. With the exception of a few embankments used for the pipe line which discharged the residue, the general upland region is comparatively level. Along the lake shore footslopes, terraces and ravines are evident where the soil is better drained than the main upland area of the fill.