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204 A. Lillehammer carnivorous species present, since Siphonoperla burmeisteri was said by Brinck (1949) to be omnivorous. The fauna1 elements of Tosketjonnbekken were also taken in relatively high numbers. The only rare species was the omnivore Isoperla grammatica. The association was, however, dominated by other species than Byrkjelandselv, namely by Leuctra hippopus and to a certain extent by Brachyptera risi. The two streams are very different. Byrkjelandselven (stream) has by far the greater water volume and along the banks of the stream there is a dense fringe of deciduous trees. The banks of Tosketjonnbekken support only isolated willow bushes among vegetation dominated by heather. In the central area 14 species were found. In one of the streams, Sandeidelven, all of them were represented. In this stream Leuctra hippopus was the most common species, followed by Brachyptera risi. The carnivore Diura nanseni, which was absent in the coastal area, was present in the central area, as are the herbivores Amphinemura borealis, Leuctra nigra and N emurella picteti. In the inner lowland areas, Hogganvikbekken (stream) is the same size as Tosketjonnbekken, while Nordelva and Storelva are larger. In Hogg-anviksbekken 12 species were taken, while in Storelva there were 16 species, and in Nordelva 17 species. Among the species of the area not present in Hogganviksbekken, 'Taeniopteryx nebulosa, Capnia pygmaea, Leuctra fusca, Isoperla grammatica and Isoperla obscura, only I. obscura seems to be restricted to larger streams, as all the other species were also taken in small streams in the area. Of the total fauna in the lowland area it seems to be only this species whose presence depends on stream size. The differences between the outer and inner areas in species composition, such as the absence of Amphinemura borealis, Diura nanseni, Leuctra nigra and N emurella picteti from the coastal area, must be attributed to other factors, such as climatic, vegetation and substratum. In the inner area, lowland Leuctra hippopus, Leuctra fusca and Brachyptera risi are the most common species. The great differences in altitude in the inner parts produce considerable differences in the faunal associations. There are 17 species at altitudes from 0-50 m (Storelva and Nordelva). At a height of about 700 m above sea level there are only 8 species. At higher altitudes the reduction continues, with fewer individuals of the few species still present. To determine zonation trends, investigation of vertical distribution was carried out and compared with the floristic zonation described by Sjors (1963) and Gja:revoll (1973). The results will be presented and discussed later. Area 2. 'The surroundings of the Oslofjord This is a lowland area consisting of inner fjord and coastal areas chosen for comparison with the lowlands of area 1. The vegetation is that of the Boreo-Nemoral zone, which is the same as most of southern Sweden. Area Description The area (Fig. 4) consists of 3 parts: 2.1, the area around the inner Oslofjord; 2.2, the area 'around the lower parts of the river Glama. The localities in these two areas are situated in the counties of 0stfold and Akershus; 2.3, the western coastal areas which are situated in the county of Vestfold. In these areas 34 streams were investigated. The bedrock in the region to the north and west of the Oslofjord consists of slightly altered calcareous Cambro-Silurian rocks interspersed by areas of igneous rocks. On the east side gneiss predominates. Near the fjord on both sides there are significant deposits of marine clay (Holtedal 1960). The coastal areas (2.3) have a mean January temperature which is slightly above 0° C, while in the inner area (2.1) the mean January temperature lies around _5° C. In area 2.2 the mean January temperature ranges from a little above 0° C in the southern parts to below _5° C in the northern parts. The whole area lies within the July isotherm of 15° C. In the area to the west of the Oslofjord, precipitation is 800-1200 mm a year. In the area to the east of the Oslofjord the precipitation is lower, between 400 and 800 mm a year. Most of the region is lowland with extensive areas of drift material except for a number of cliffs on both sides of the Oslo
Norwegian stoneflies If 205 fjord. In the coastal parts the cliffs seldom reach over 200 m a.s.l. Nearer Oslo the hills are somewhat higher, from 300-400 m a.s.l. North of Oslo elevations between 500 and 700 m a.s.l. are reached. The flatter parts of all three areas are intensively cultivated. This is most pronounced in the central regions of Vestfold and 0stfold. Nearer the coast there are small areas rich in deciduous trees; otherwise spruce-dominated coniferous forests predominate above the cultivated areas. Stream descriptions The streams in the area around the inner Oslofjord (2.1) rise in hills where spruce and pine are dominant. Where the streams flow through cultivated areas there is often a dense fringe of deciduous trees, usually alder, along their banks. Streams where pollution is relatively mild are still to be found. The streams in the eastern parts of 2.2 rise largely from boggy, spruce forest areas. The streams in the central parts run through cultivated areas and are usually markedly polluted. The streams of area 2.3 are usually smaller than in the other areas and there is a dense band of deciduous trees along the streams. The pollution is relatively mild. In all three areas the stream substratum varies from sand and gravel to larger stones. Calcium hardness and pH vary considerably. At low water levels prior to snow melting, calcium hardness values over 1 mg Ca++/l are common in the inner area (2.1). The highest value recorded was 12.2 mg Ca+ + /1. In the coastal areas the values were even higher, ranging from 3.1 to 16.1 mg Ca + + /1. In the eastern area the values were markedly lower, from 0.4 to 1.7 mg Ca+ + /1. In this area pH varied between 5.0 and 7.0, the higher values being recorded in streams on marine deposits. On average pH was somewhat lower than in the other two areas. Measurements of pH in Vestfold (2.3) lay between 6.4 and 7.1 and in area 2.1 between 5.5 and 7.6. Stonefly fauna Area 2 contains 24 species of Plecoptera (Table IV). There are marked differences between the three parts of the area. In areas 2.1 and 2.2 there are nearly the same number of species, 22 and 21 respectively. The differences in this case are that N emoura flexuosa. Amphinemura standfussi and Capnia bifrons have been taken in area 2.1, but not in area 2.2. The opposite is true of Isogenus nubecula and Isoperla obscura. The most striking difference between areas 2.1 and 2.2 is the dominating position of the Capniids in the former area. In area 2.1 Capnia atra, C. bifrons and Capnopsis schilleri are to be found in nearly every stream investigated, with some dominated by Capnia bifrons and Capnopsis schilleri such as S
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451 1 I I I I I I I 4 6 8 10 12 14
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Dry Weight , mg. Fig. 7. Correlatio
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Table 11. Caloric values per g dry
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Talbe IV. Oxygen consumption given
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etween the sexes during the respira
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128 A. Fjellberg Fig. 2. A. sefiten
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130 A. Fjellberg HABITATS Until now
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132 L. Semme the autumn. The prelim
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'~0~1-0611 '96 'lourouy 'uu3 's3asu
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136 J. E. Brittain Fig. 1. The loca
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138 J. E. Brittain period was longe
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140 J. E. Brittain Table 11. Ph~sic
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142 J. E. Brittain Table IV. Physic
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144 J. E. Brittain EPHEMEROPTERA Am
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146 J. E. Brittain 0-3 NYMPHS I I 1
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148 J. E. Brittain 1-3 NYMPHS 01 I
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150 J. E. Brittain Nemzlrella picte
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152 J. E. Brittain ture and the inc
Page 40 and 41: (Nord-Norwegen) (Trichoptera, Pleco
Page 42 and 43: from anoxia. Drops of haemolymph we
Page 45 and 46: Notes on little known spiders in No
Page 47 and 48: Symphyla and Pauropoda from two con
Page 49 and 50: Symphyla and Pauropoda 163 Table 11
Page 51: sults it is clear that the animals
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Page 59 and 60: Abundance and diversity in the faun
Page 61 and 62: Nocturnal moths 175 Table 1. Number
Page 63 and 64: Nocturnal moths 177 Grimstad Amli 1
Page 65 and 66: Nocturnal moths 179 Am/i. Norway 19
Page 67 and 68: Nocturnal moths 181 Grimstad, Norwa
Page 69 and 70: Nocturnal moths 183 %60 50 40 30 20
Page 71 and 72: Spinosellina forms of Sminthurides
Page 73 and 74: A constant pressure microrespiromet
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Page 78 and 79: 192 F. E. Klallsen The specimens fr
Page 80 and 81: 194 F. E. Klausen REFERENCES Ardii,
Page 82 and 83: 196 A. Lillehammer present in Norwa
Page 84 and 85: 198 A. Lillehammer Results The numb
Page 86 and 87: 200 A. Lillehammer Fennoscandian co
Page 88 and 89: 202 A. Lillehammer parts of the are
Page 92 and 93: Table IV. Species distribution, in
Page 94 and 95: Table V. Species distribution in se
Page 96 and 97: 210 A. Lillehammer The bottom of th
Page 98 and 99: 212 A. Lillehammer Blatjemn Diura b
Page 100 and 101: Table VII. Species distribution in
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Page 104 and 105: Table IX. Species distribution in s
Page 106 and 107: 220 A. Lillehammer same latitude as
Page 108 and 109: 222 A. Lillehammer Table XI. The pH
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Page 112 and 113: 226 A. Lillehammer Table XVI. The s
Page 114 and 115: 228 A. Lillehammer Fig. 22. Stream
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Page 130 and 131: 244 A. Lillehammer streams and rive
Page 132 and 133: 246 A. Lillehammer Blies (1953, 195
Page 134 and 135: 248 A. Lillehammer streams are to a
Page 136 and 137: 250 A. Lillehammer Muller, K. 1955.
Page 138 and 139: 252 Bokanmeldelser produserende, en
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N orsk Entomologisk Tidsskrift Norw
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