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In this study, influence of slope position (south-facing vs. north-facing), species type and sampling time on fine (0-2 mm), small (2-5 mm) and coarse (5-10 mm) root biomass and carbon storage of oriental spruce (Picea orientalis) and oriental beech (Fagus orientalis) were investigated. Mean total root biomass of oriental spruce was 20160 kg ha(-1) in south-facing slopes and 17140 kg ha(-1) in north-facing slopes. Mean total belowground C storage of oriental spruce was 7861 kg ha(-1) in south-facing slopes and 6840 kg ha(-1) in north-facing slopes. Similarly, biomass and C storage of oriental beech were 17190 and 6690 kg ha(-1) in south-facing slopes, and 13260 and 5200 kg ha(-1) in north-facing slopes, respectively. Oriental spruce had significantly higher fine root biomass than did oriental beech in south-facing slopes. Fine root biomass was significantly higher in fall than in spring in south-facing slopes.  相似文献   
2.
A study concerning the effects of elevation and exposure of the spruce forests on defoliation levels of oriental spruce (Picea orientalis (L.) Link.) by Ips typographus L. was carried out during 2005 and 2006 in Artvin-Hatila National Park, Turkey Nine spruce stands were selected at 3 zones of elevations (1000-1350 m, 1350-1700 m and 1700-2000 m) and at different aspects to assess the role of elevation and exposure in the crown defoliation level and body length of beetles. Influence of bark thickness and trunk diameter at 1.3 m on the damage caused by the pest was investigated as well. The results of the study were as follows: (1) The mean defoliation level was highest at 1700-2000 m following by 1350-1700 m and 1000-1350 m. (2) The highest defoliation levels occurred on southern slopes following by eastern and northern slopes at 1700-2000 m. (3) No statistical differences were found in the mean bark thickness between tree defoliation levels 1, 2, 3 and 4. (4) Mean trunk diameters of dead trees (level 4) were significantly greater than those with defoliation levels 0, 1 and 2. (5) Mean body length of I. typographus at upper zones was significantly higher than those at middle and lower zones.  相似文献   
3.
In this study, three thinning treatments were applied on a 0.54 ha young oriental beech (Fagus orientalis Lipsky) stand (25-30 years old) in Karadag, Artvin in the fall of 1999. The treatments were: (1) no thinning, (2) light thinning, and (3) heavy thinning. Prior to thinning, the stand averaged 15000 trees ha(-1) and 40.0 m2 ha(-1) of basal area, with an average mean diameter of 5 cm. Thinning reduced stand basal areas to about 31.1 and 24.9 m2 ha(-1) for the light and heavy thinning treatments, respectively. After 3-years, diameter increment was the highest in heavily thinned stand and the lowest in unthinned stand. The increment in stand basal area was about 10, 18 and 27% in the unthinned, lightly thinned, and heavily thinned stands, respectively. Fine root biomass significantly decreased with thinning and thinning had no significant effects on soil pH and soil organic matter content.  相似文献   
4.
Cu accumulation and depuration in various tissues of the crayfish Astacus leptodactylus was investigated. Adult specimens were exposed to 0.5, 2.5 and 5.0 mg Cu/L under static conditions for three weeks. At the end of the 3rd week the specimens were divided into three groups and left in dechlorinated water for either 1, 2 or 3 weeks for depuration. After 7, 14 and 21 days, four crayfish from each group were instantaneously sacrificed. All crayfish were dissected into their hepatopancreas, gill, abdominal muscle and exoskeleton tissues for evaluation of Cu accumulation in each. The following accumulation pattern was obtained in decreasing order; hepatopancreas > gills > exoskeleton > abdominal muscles with values of 94.13, 84.86, 66.13 and 11.43 mg/L, respectively. The observed Cu depuration throughout the study was found to be time-dependent. Based on the present work we conclude that crayfish has a great potential for rapid accumulation and depuration of Cu in fresh water.  相似文献   
5.
Environmental Science and Pollution Research - Global warming has become the center of worldwide environmental concerns, especially in recent years. One of the ways to deal with global warming that...  相似文献   
6.
Micronuclei tests is a system of mutagenicity testing used for determining the pollution and chemicals causing changes in DNA fragments such as micronuclei in the cytoplasm of interphase cells. Damage caused on the DNA by genotoxic pollutants is the first consequence occurring in the aquatic organisms. Thus, it was attempted to determine whether pollution affected the erythrocytes and gills of fish Gobius niger and haemolymph and gills of mussels Mytilus galloprovincialis living in Izmir Bay at the level of DNA by the means of micronuclei (MN) test. Organisms used in the MN test were collected from seven locations (Alsancak, Alaybey Shipyard, Karsiyaka, Bostanli, Göztepe, Konak and Pasaport) which are known as the most polluted part of inner Bay of Izmir (Western Coast of Turkey). According to the results of the present study, frequency of MN was found at high level in Alaybey Shipyard and Pasaport where wastes from existing dockyard contributed to high level of pollution. In conclusion, this study indicates that the micronuclei test gives sensitive results in monitoring the pollution, especially the pollution of harbor, and thus it might be used as standard method in regular monitoring of pollution of coastal ecosystem.  相似文献   
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