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1.
Larionova AIa 《Genetika》2002,38(12):1641-1647
The main parameters of genetic variability have been determined in an isolated natural Scotch pine population from Chita oblast' (Tsasuchei Forest) by analysis of 19 genes coding for nine enzymes: GDH, IDH, LAP, PGM, AAT, ADH, MDH, 6-PGD, and DIA. Polymorphic genes constituted 63.2% of all structural genes studied in the population at the 99% polymorphism criterion. The mean number of alleles per locus was 1.63. The observed and expected heterozygosities were 0.237 and 0.251, respectively. These estimates are close to the corresponding mean values for Scotch pine according to the data on 18 or more structural genes.  相似文献   

2.
应用空间直观景观模型(LANDIS)模拟了1987年大兴安岭北坡图强林业局特大森林火灾后在目前种植强度下,不同落叶松和樟子松种植比例(100%落叶松(P1)、70%落叶松和30%樟子松(P2)、50%落叶松和50%樟子松(P3)、30%落叶松和70%樟子松(P4)、100%樟子松(P5)以及完全依靠天然更新(P0)条件下森林景观的长期动态变化.结果表明,在演替的前期、中期和后期,不同种植比例均对落叶松、樟子松和白桦有显著影响;落叶松所占的面积百分比随时间的推移均呈上升趋势,而樟子松则相反;在各种植预案下,落叶松和樟子松的面积百分比均高于天然更新预案的比例,随着落叶松种植比例的增加,落叶松的多度也相应增加;樟子松在该区所占的面积百分比也随其种植比例的增大而增加.白桦在天然更新预案下所占的面积百分比明显高于种植预案下所占的比例;而不同落叶松和樟子松种植比例也对白桦面积有较大影响,樟子松种植的比例越大,白桦所占的面积百分比越高,说明落叶松比樟子松有更强的竞争能力.但P2、P3和P4预案下,落叶松和樟子松的面积所占比例相差不大,但要高于完全种植落叶松(P1)或樟子松(P5)所占的比例.  相似文献   

3.
Mature trees of eastern white, jack, Scotch, and shortleaf pines were inoculated with 25,000-34,000 pinewood nematodes, Bursaphelenchus xylophilus, isolated from infected Scotch pines in Missouri. Equal numbers of trees of each species inoculated with distilled water served as controls. Nine of fifteen Scotch pines died within 4 months of nematode infection or during the winter and early spring following infection. A single eastern white and shortleaf pine died. No jack pines died. A single Scotch pine control died, apparently the result of natural nematode infection. No other controls died. Mean oleoresin flow did not differ among nematode-inoculated jack and shortleaf pines and their respective controls. Oleoresin flow in nematode-inoculated eastern white and Scotch pines was significantly lower than in their controls. Oleoresin flow was temporarily reduced in mortality-resistant eastern white and Scotch pines following nematode infection. Thus a sublethal impact of nematode infection on mortality-resistant host trees was documented.  相似文献   

4.
联合GF-6和Sentinel-2红边波段的森林地上生物量反演   总被引:1,自引:0,他引:1  
光谱反射率能反映地物差异,是森林地上生物量(Aboveground Biomass,AGB)遥感反演的理论基础。红边波段处于近红外与红光波段交界处快速变化的区域,能对植被冠层结构和叶绿素含量的微小变化做出快速反应,对植被生长状况较敏感。研究以GF-6和Sentinel-2多光谱影像作为数据源,结合野外调查AGB数据,构建落叶松和樟子松AGB线性和非线性估测模型,通过比较模型精度选择最优模型进行森林AGB反演和空间分布制图。结果表明:GF-6和Sentinel-2影像红边波段反射率与落叶松、樟子松AGB均呈显著相关(P<0.05),红边波段对AGB估测较敏感。多变量估测模型整体估测效果优于单变量模型,所有模型中多元线性回归模型取得了最优的决定系数(落叶松R2=0.66,樟子松R2=0.65)和最低的均方根误差(落叶松RMSE=31.45 t/hm2,樟子松RMSE=54.77 t/hm2)。相比单个数据源,联合GF-6和Sentinel-2影像构建的多元线性回归模型估测效果得到了显著提升,模型RMSE对于落叶松和樟子松AGB估测分别最大降低了22.9%和11.2%。增加红边波段进行AGB估测能显著提高模型估测精度,三组数据源分别加入红边波段信息后进行建模,模型RMSE得到了显著降低。GF-6拥有800 km观测幅宽和高效的重访周期,可以快速地提供大尺度时间序列数据,在森林地上生物量反演和动态监测方面有着很大潜力。  相似文献   

5.
The effect of surface fires of different intensity on soil invertebrates was evaluated in central taiga Scotch pine forests in the Yenisey Region of Siberia. In the period of 4–5 years, the abundance and ecological and trophic structure of sandy podzol population was almost completely restored after surface fires of medium and low intensity. The recovery process was decelerated after high intensity fires.  相似文献   

6.
外生菌根菌不同接种方法对樟子松苗木生长的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
 以提高外生菌根真菌对樟子松(Pinus sylvestris var. mongolica)苗木促生长效果为目的, 在前期研究的基础上, 采用菌株配对培养的方法对获得的樟子松外生菌根真菌进行混合接种菌株组合筛选; 采用苗木截根-菌液浸根和沟施接种方法分别对2年生和3年生樟子松苗木进行野外单接种及混合接种。研究外生菌根真菌不同接种方法、菌株单接种及混合接种对樟子松苗木生长的影响。试验结果表明: 供试菌株及菌株组合对樟子松苗木生长均有一定的促进作用。菌株GT005和菌株035为供试菌株中对樟子松苗木促生长效果最佳的菌株。采用苗木截根-菌液浸根方法接种2年生樟子松苗木130 d, GT005接种的苗木高生长提高54%, 地径生长提高15%, 过氧化氢酶活性提高48%, 而根系活力降低3%; 菌株035接种的苗木高生长提高42%, 地径生长提高56%, 过氧化氢酶活性提高47%, 根系活力提高11%。沟施接种方法接种3年生樟子松苗木100 d, GT005接种苗木高生长提高10%, 地径生长提高15%, 过氧化氢酶活性提高90%, 而根系活力降低34%; 菌株035接种苗木高生长提高7%, 地径生长提高9%, 过氧化氢酶活性提高6%, 而根系活力降低46%; 菌株组合044/GT001和GT001/GT005 接种的苗木高生长仅比对照提高3.47%和2.07%, 而菌株组合 044/025 和044/009 接种的苗木高生长低于对照; 混合接种的苗木其地径生长高于对照0.16%~7.98%。综上所述, 苗木截根-菌液浸根接种方法对苗木的促生长效果显著高于沟施接种方法; 外生菌根菌高效菌株与一般菌株混合接种会弱化高效菌株自身接种效果; 苗木过氧化氢酶活性、苗木根系活力与苗木的生物量间无相关性。  相似文献   

7.
The data on the cytogenetic monitoring of the Usmansky and Khrenovskoy autochthonic pine stands (Voronezh Region) allow their status to be rated satisfactory. The indices of the mitotic and nucleolar activity as well as of abnormal mitosis were within the normal variation range for Scotch pine. However, the occurrence of micronuclei (less than 1%) points to pathological processes starting in the stands, which necessitates urgent measures for the conservation of the Usmansky and Khrenovskoy Forests as valuable gene sources.  相似文献   

8.
The emission of reduced volatile sulfur compounds from twigs of Norway spruce (Picea abies (L.) Karst.) was measured in the field by cryosampling and gaschromatographic analysis. Trees were growing in the Erzgebirge (E-Germany) at Oberbärenburg and at the Kahleberg and at a third stand in NW-Bavaria (S-Germany). Emission rates were also measured for Scotch pine (Pinus sylvestris L.) and Blue spruce (Picea pungens Engelm.) at the Kahleberg. Twigs still attached to the trees were enclosed in a flow-through gas exchange cuvette. H2S was detected as the predominant reduced sulfur compound emitted from the twigs. The mean H2S emission rate from twigs of Norway spruce varied between 0.04 pmol kg-1 dw s-1 at Würzburg and 6.21 pmol kg-1 dw s-1 at the Kahleberg. Comparing different species at the Kahleberg, the mean H2S emission rate was almost the same from twigs of Norway spruce (6.2 pmol kg-1 dw s-1) and Blue Spruce trees (5.9 pmol kg-1 dw s-1) but it was approximately 18 times higher for Scotch pine (110 pmol kg-1 dw s-1). The percentage of SO2-exclusion via H2S-emission of the tree species investigated at the Kahleberg is calculated on the basis of data on SO2 fluxes. It is very small for Norway spruce and Blue spruce. However, for Scotch pine, H2S emission contributes about 10% to the detoxification of SO2.  相似文献   

9.
Gamma irradiation of Scotch spearmint created a mutant line, 643-10-74, which has an altered essential oil reminiscent of peppermint because the monoterpene metabolites in the oil glands of the mutant are predominantly oxygenated at the C3 position of the p-menthane ring instead of the C6 position normally found in spearmint. The limonene hydroxylase genes responsible for directing the regiochemistry of oxygenation were cloned from Scotch spearmint and mutant 643 and expressed in Escherichia coli. The limonene bydroxylase from the wild-type parent hydroxylated the C6 position while the enzyme from the mutant oxygenated the C3 position. Comparison of the amino acid sequences with other limonene hydroxylases showed that the mutant enzyme was more closely related to the peppermint limonene-3-hydroxylases than to the spearmint limonene-6-hydroxylases. Because of the sequence differences between the Scotch spearmint and mutant 643 limonene hydroxylases, it is most likely that the mutation did not occur within the structural gene for limonene hydroxylase but rather at a regulatory site within the genome that controls the expression of one or the other regiospecific variants.  相似文献   

10.
The morphological and functional organization of the needles of Scotch pine (Pinus sylvestris L.) and Siberian fir (Abies sibirica Ledeb.), which differ in their light requirement were studied. The characteristic properties of the high-light-requiring pine included high rates of apparent photosynthesis and dark respiration, high assimilation number, numerous folds in mesophyll cell walls, and increased partial volume of intercellular spaces and hyaloplasm in the mesophyll. In the needles of shade-enduring fir, the higher efficiency of photosynthesis at low light intensities depended on the higher number of membranes and higher pigment content in the chloroplasts. The low assimilation number in fir indicated a shortage of photosynthetic reaction centers. The relative volume of the vascular cylinder and the vascular bundles in the needles and the partial volume of chloroplasts in the hyaloplasm, are considered as indices of the rate of assimilate export from mesophyll cells and their possible damping at different levels of structural organization.  相似文献   

11.
The morphometric parameters of trunk tissues of Scotch pine in suburban pine forests of Krasnoyarsk are studied, which grow under the long-term impact of technogenic and recreational loads in comparison with the background. Technogenic and recreational loads decrease the intensity of work of the cambium, especially towards the xylem, its duration, the cell size, and the structure of storage tissues. In pine stands of the Krasnoyarsk forest-steppe, the effect of the complex of anthropogenic stressors is weakening and degradation of forest stands and inhibition of production process at the cell and tissue levels are taking place.  相似文献   

12.
Russian Journal of Bioorganic Chemistry - The isolation of proanthocyanidins from the bark of Scotch pine Pinus sylvestris L. by water and water–alcohol solutions containing 5, 10, 15, 20,...  相似文献   

13.
14.
Geras’kin  S. A.  Vanina  J. C.  Dikarev  V. G.  Novikova  T. A.  Oudalova  A. A.  Spiridonov  S. I. 《Biophysics》2010,55(2):324-331
The method of isozyme analysis of megagametophytes is used to estimate the genetic variability in Scotch pine populations (Pinus sylvestris L.) of the Bryansk Region sites with contrasting levels of radioactive contamination (soil 137Cs, 60 to 17 800 Bq/kg) resulting from the Chernobyl accident. All indices of genetic variability (heterozygosity, frequency of polymorphic loci, Zhivotovskii index) and frequencies of loss-of-function enzyme mutations increase with the dose absorbed by plant generative organs. The data show that high mutability is intrinsic for seeds of these pine trees, and genetic diversity in the populations is essentially conditioned by radiation exposure.  相似文献   

15.
The influence of technology factors on the yield of pectin substances from Scotch pine arboreal greenery has been investigated. The following conditions are recommended as necessary for the high yield of pectin substances: a period of hydrolysis-extraction of no less than 1 h and a temperature of 80°C at a fluid modulus of 1: 7.  相似文献   

16.
Korshikov II  Pirko IaV 《Genetika》2002,38(9):1235-1241
Based on electrophoretic analysis of 21 isozyme loci controlling 10 enzyme systems, the intra- and inter-population variation was studied in two peat-bog and three dry-meadow populations of the dwarf mountain pine Pinus mugo Turra from the highlands of the Ukrainian Carpathians. In the studied samples (a total of 164 trees), on average 62% of the studied genes were polymorphic; the mean heterozygosity was 21.3%. The dry-meadow populations differed from the peat-bog populations by allele and genotype diversity and by heterozygosity although the indices characterizing population heterogeneity (Fst and Gst) were small (0.027 and 0.032, respectively). Nei's genetic distances between the populations ranged of 0.011 to 0.032 with the mean of 0.018.  相似文献   

17.
The presence of major genes affecting rust resistance of loblolly pine was investigated in a progeny population that was generated with a half-diallel mating of six parents. A Bayesian complex segregation analysis was used to make inference about a mixed inheritance model (MIM) that included polygenic effects and a single major gene effect. Marginalizations were achieved by using Gibbs sampler. A parent block sampling by which genotypes of a parent and its offspring were sampled jointly was implemented to improve mixing. The MIM was compared with a pure polygenic model (PM) using Bayes factor. Results showed that the MIM was a better model to explain the inheritance of rust resistance than the pure PM in the diallel population. A large major gene variance component estimate (> 50% of total variance), indicated the existence of major genes for rust resistance in the studied loblolly pine population. Based on estimations of parental genotypes, it appears that there may be two or more major genes affecting disease phenotypes in this diallel population.  相似文献   

18.
1987年大兴安岭特大火灾后北坡森林景观生态恢复评价   总被引:1,自引:0,他引:1  
王绪高  李秀珍  贺红士  解伏菊 《生态学报》2005,25(11):3098-3106
通过空间直观景观模型(LAND IS)来探讨大兴安岭北坡1987年特大森林火灾后,在目前这种恢复方案下以及完全依靠天然更新下森林景观的长期动态,通过对比研究来评价目前所采取的恢复措施是否能够有效地恢复森林资源。研究结果表明:1987年大火后所采取的恢复措施可以在很大程度上增加针叶树种在该区所占的比例,而相应地降低阔叶树种的比重。由于在目前的恢复措施下,不仅大面积地种植针叶树种,同时也采伐了大量的成、过熟林,使落叶松和樟子松的蓄积量在开始阶段不仅没有增加,反而有大幅度的下降。但最终,所更新的幼苗逐渐成材,落叶松和樟子松的蓄积量逐渐超过天然更新下的。在演替前期,白桦的蓄积量在这2种模拟方案下相差不大;而在演替后期,白桦在天然更新方案下的蓄积量要高于在目前恢复措施下的蓄积量。另外,物种在不同的区域的变化动态又有较大的差异。在重度火烧区,由于人为种植大量的针叶树种,使它们所占的面积比例明显高于完全依靠天然更新下其在重度火烧区所占的比例;而阔叶树种则相反,在完全依靠天然更新方案下所占的面积百分比明显高于在目前恢复方案下的比例。而在未火烧和轻中度火烧区,由于火后人为采伐大量的落叶松和樟子松,使这2个树种在该区所占的比例在开始100多年里要低于完全依靠天然更新下的比例,随后逐渐高于天然更新下所占的比例,但相差不大;阔叶树种则正好相反。另外,目前恢复方案不仅极大地改变了主要物种在该区所占的比例,而且还明显的影响了它们的空间分布格局。  相似文献   

19.
A reconstruction of forest-cover dynamics in the northern part of the Kas River basin has been done for the first time. This study based on a palynological analysis of the peat profile. Six pollen zones and respective phases of forest evolution are distinguished. It is inferred that changes in the forest species composition over the last 8000 years were determined by variations in the global and regional climate. The warm and humid climate of the Atlantic period promoted the development of dark coniferous birch-spruce-fir forests. Cooling and smaller precipitation in the Subboreal period led to a change in dominant species to Scotch pine and birch-Siberian pine forests with an admixture of spruce and fir. In the Subatlantic period, closed coniferous forests eventually evolved, with Siberian pine-pine remaining dominant.  相似文献   

20.
Overwintering behavior of Tomicus piniperda (L.) was studied in a Scotch pine (Pinus sylvestris L.) Christmas tree plantation in Indiana (1992-1994) and a plantation in Michigan (1994). In general, adults feed inside shoots during summer, then move to overwintering sites at the base of trees in autumn. In early autumn, adults were most often found in shoot-feeding tunnels that were still surrounded by green needles, whereas few were in tunnels surrounded by yellow or brown needles. For all years and sites combined, the range in the percentage of recently tunneled shoots that contained live T. piniperda adults decreased from 89 to 96% in mid-October, to 15- 66% in early November, to 2-10% in mid-November, and to 0-2% by late November to early December. In each year, the first subfreezing temperatures in autumn occurred in October, before most adults left the shoots. Of 1,285 T. piniperda-tunneled shoots, one to seven tunnels (mean = 1.6) and zero to three adults were found per infested shoot. Of these 1,285 attacked shoots, 55% of the shoots had one tunnel, 33% had two, 9% had three, 3% had four, and <1% had five to seven tunnels each. When two or more tunnels occurred in a single shoot, adults were most commonly found in the innermost (most basal) tunnel. For the 2,070 tunnels found in the 1,285 shoots, average shoot thickness at the tunnel entrance was 6.0 mm, average distance from the tunnel entrance to the shoot tip was 6.3 cm, and average tunnel length was 2.3 cm. Four Scotch pine Christmas trees were dissected in January 1993. Eighty percent of the tunneled shoots were in the upper quarter of the tree crown and 98% were in the upper half. For the four trees inspected in January, one live adult was found in a shoot and 85 adults were found in the outer bark along the lower trunk from 1 cm below the soil line to 19 cm above the soil line. No overwintering adults were found outside the trunk in the duff or soil near the base of each test tree. Implications of these results are discussed in terms of surveying, timing the cutting of Christmas trees, and cutting height for Christmas trees.  相似文献   

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