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246 HILMAR HOLMENTABLE I. Soil characteristics below a belt transect from an Aconitum-Lactuca to a . Ore pis community.Altitude 525 m. See Fig. 5.Soil Depth of Loss onsampled sample Horizon ignitionat cm %pHN p K Ca% ofl.o.i.% of dry weight2 m 5- 8 Al + A 2 14.5ll-14 Aj(B) 6.035-40 (B)70-75 c4m 1- 5 A1 + A 2 34.830-34 (B) 13.849-53 c6.1 3.10 0.07 0.09 0.466 . 1 3.33 0.04 0.16 0.326.36.46 . 1 2.76 0.12 0.11 0.176.8 3.03 0.12 0.18 0.517.0Within the 5 to 10 m stretch of the transect thesurface soil has the appearance of fen peat. Thepeat is quite amorphous, indicating a good aeration.The water flush moves at times on or near the soilsurface (see Fig. 5) and because of the slope itreceives a fairly high speed, as observed when thepits were dug. The amorphous organic layer hashere a thickness varying between 25 and 35 cm.The analyses of the streaming water reveal a considerableinfluence from the calcareous substrate,specific conductivity as well as pH and calciumcontent being fairly high. The contents of othercations should be regarded as being normal for nonpollutedwaters in forest areas (TROEDSSON 1955).TABLE 2. Chemical properties of the soil water.pH%20 . 106Dry matter, mg/1Ash, mg/16.810569.562.5Ca, mgflMg, mg/1Na, mg/1K, mg/117.51.453.651.05Soil analyses from sample plots within theAconitum - Lactuca community show a considerablevariation in chemical properties. Table 3 concernseight brown earth profiles, minimum and maximumvalues being reported. The symbols for the horizonsrefer to the general designation in soil profileselaborated by KuBIENA (1950, pp. 25 ff.).ANALYTICAL REMARKS.-pH was determined electrometricallyon dried samples suspended in distilledwater. Volume ratio soil/suspension was 1:2. Loss onignition was obtained by igniting the samples at about550°C to constant weight. Nitrogen was determinedby the Kjeldahl method and calculated on loss onignition for soil samples and on dry matter for plantsamples. Minerals were determined by wet ashingwith 25 ml cone. nitric acid and 5-10 ml perchloricacid (C. 0. TAMM 1953, p. 13).The figures for loss on ignition and nitrogen agreefairly well with forest mull analyses by SJORS(1961 a, p. 46). However, most of his phosphorusvalues are higher. Unfortunately SJORS did notdetermine the total contents of potassium andcalcium but only the exchangeable part. MALM­STROM (1949, p. 175) has presented some analysesfrom Aconitum forests in N Sweden showingphosphorus contents of O.ll-0.15% and potassiumcontents of 0.12-0.26 % in the humus layer, inclose agreement with the values from the Ankarvattnetarea.Analyses from layers below A1 +A2 are uncommonin the relevant literature. From an investigationin N Lappland (unpublished) where onlypodsols were studied, the following ranges wereobtained for the A1 + A2 and B horizons: Loss onignition 1.2-7.0 %, pH 3.8-5.7, N 0.99-2.38 %, P0.01-0.16, K 0.04-0.23 %, Ca 0.04-0.75 %. Fromthese values and MALMSTROM's (1949, 1963) humusand mineral soil analyses it is evident that pH,nitrogen and calcium are usually higher in brownearths than in podsols. Phosphorus and potassiumare more irregular.Some profiles which morphologically are transitionaltypes between brown earth and podsol werealso studied. They differ from the brown earthprofiles proper only in having low pH (4.7-5.3) andActa Phytogeogr. Suec. 50