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1.
The early post-fire development of mycobiota following a crown fire in mountain pine plantations and a surface fire in Scots pine plantations, and in the corresponding unburnt stands in the coastal sand dunes of the Curonian Spit in western Lithuania was investigated. Species numbers in unburnt Pinus mugo and Pinus sylvestris stands showed annual fluctuation, but in the burnt sites, the numbers of fungi increased yearly, especially in the crown fire plots. Both burnt stand types—P. mugo and P. sylvestris—showed strongly significant (two-way ANOSIM; R = 1, p < 0.05) differences in species composition; the differences between unburnt sites were clearly expressed but less significant (R = 0.86, p < 0.05). Fungal species composition of burnt P. mugo and P. sylvestris sites was qualitatively different from that of corresponding unburnt sites (two-way ANOSIM; R ≥ 0.75, p < 0.05). The chronosequence of mycobiota in surface fire burns was less clearly defined than in crown fire sites, reflecting the greater patchiness of impacts of the surface fire. Although both fire types were detrimental or at least damaging to all functional groups of fungi (saprobic on soil and forest litter, wood-inhabiting, biotrophic, and mycorrhizal and lichenized fungi), their recovery and appearance (fructification) patterns varied between the groups and among the burn types. The end of the early post-fire fungal succession (cessation of sporocarp production of pyrophilous fungi) was recorded 3 years after the fire for both crown and surface fire types, which is earlier than reported by other authors. Rare or threatened fungal species that are dependent on fire regime were not recorded during the study.  相似文献   

2.
以黑龙江省兴隆林业局为例,从5个方面介绍了抚育采伐对人工樟子松林分生长各项指标、林内环境、林分的稳定性、木材质量和抚育伐总生长量的影响。同时指出,对樟子松进行适时合理抚育伐,可以促进林木生长,提高林分质量,实现早成材早利用。  相似文献   

3.
The taiga coniferous forests of the Siberian region are the main carbon sinks in the forest ecosystems.Quantitatively, the size of the carbon accumulation is determined by the photosynthetic productivity, which is strongly influenced by environmental factors. As a result,an assessment of the relationship between environmental factors and photosynthetic productivity makes it possible to calculate and even predict carbon sinks in coniferous forests at the regional level. However, at various stages of the vegetative period, the force of the connection between environmental conditions and the productivity of photosynthesis may change. In this research, correlations between the photosynthetic activity of Scots pine(Pinus sylvestris L.) with the environmental conditions were compared in spring and in autumn. In spring, close positive correlation of the maximum daily net photosynthesis was identified with only one environmental factor. For different years, correlations were for soil temperature(rs= 0.655,p = 0.00315) or available soil water supply(rs= 0.892,p = 0.0068). In autumn within different years, significant correlation was shown with two(temperature of air and soil; rs= 0.789 and 0.896, p = 0.00045 and 0.000006,respectively) and four factors: temperature of air(rs=0.749, p = 0.00129) and soil(rs= 0.84, p = 0.00000),available soil water supply(rs= 0.846, p = 0.00013) and irradiance(rs= 0.826, p = 0.000001). Photosynthetic activity has a weaker connection with changes in environmental factors in the spring, as compared to autumn.This is explained by the multidirectional influence of environmental conditions on photosynthesis in this period and by the necessity of earlier photosynthesis onset, despite the unfavorable conditions. This data may be useful for predicting the flow of carbon in dependence on environmental factors in this region in spring and in autumn.  相似文献   

4.
5.
Embryogenic cultures (EC) of Scots pine (Pinus sylvestris L.) were initiated from immature embryos. Whole ovules were used as expiants. The responsive period for initiation began just after fertilization and remained throughout the development of first stages of early embryos. The main part of the embryogenic cultures were initiated by the time of cleavage polyembryony. Strong correlation was obtained between degree days and the responsive period. During subsequent years the experiments were repeated in Finland and Sweden. In all cases the responsive period for initiating embryogenic cultures was the same, about two weeks after fertilization.

In 1991–1993, a total of 138 clones of elite pine trees were tested for their ability to initiate embryogenic cultures. Of these, 33% were responsive under our experimental conditions. Based on about 300 ovules per clone the number of embryogenic lines induced by the responding clones varied from 0.2% to 9.0% of the expiants.

Several nutrient media were found to be suitable for initiation and proliferation of ECs. About half of the cell lines responded to abscisic acid by producing maturing embryos. The embryos reached full maturity in cultures of only a few cell lines. Some of the embryos that produced roots were planted in soil and transferred to a greenhouse.  相似文献   

6.
根据标准地、解析木及生物量调查资料,建立了人工樟子松林叶、枝、干及全树生物量预估模型,并对模型参数进行了小样本t检验。结果表明,地上生物量与胸径密切相关,樟子松生物量随着树龄的增长而增加,y=aDb Hc为该地区人工樟子松林叶量、枝量、干量和全树生物量的最优模型。  相似文献   

7.
A review of the literature is presented and an infection experiment described. Dwarf plants of Pinus sylvestris are seldom infected and destroyed by the snow mould fungus Phacidium infestans. The reasons are: The amount of infection material is usually small, the ecological conditions do not favour infection and subsequent development of the disease, the plants are small targets for spores and infective needles, the dwarf plants are fairly resistant.  相似文献   

8.
【目的】拓展木材显微切片的染色方法。【方法】比较研究了番红(Safranine O)、固绿(Fast Green FCF)和阿利新蓝(Alcian Blue 8GX)三种染料对樟子松木材切片的染色效果。【结果】单一染料染色时,番红对木质化程度高的厚壁细胞上色效果较好,阿利新蓝对木质化程度低的薄壁细胞上染较好,固绿介于两者之间。两种染料复染时,番红-固绿无法实现不同细胞的区分,仅呈现番红的颜色;而番红-阿利新蓝可以区分厚壁和薄壁细胞,厚壁细胞(管胞和射线管胞)呈红色,薄壁细胞(射线薄壁细胞和泌脂细胞)呈蓝绿色。进一步通过冰乙酸为复染提供一个酸性环境,改进了番红阿利新蓝双染方法。当冰乙酸含量为13%~17%时,能达到理想的染色效果,能够更加清晰地区分厚壁和薄壁细胞。分别将番红、固绿和新蓝用于已解离的管胞染色,新蓝对管胞的染色效果最好,番红染色效果比新蓝略差,固绿染色效果远低于新蓝和番红。【结论】番红对木质化程度高的厚壁管胞染色效果最好;新蓝对木质化程度低的薄壁细胞染色效果最好。改进后的番红-新蓝双染能清楚地区分木材中的厚壁和薄壁细胞。木材细胞对不同种类染料的响应各异,同时也受染色介质影响。研究结果为木材切片细胞识别提供简单高效的新方法。  相似文献   

9.
人工樟子松幼林改建红松坚果园工艺技术   总被引:1,自引:0,他引:1  
针对退耕还林后樟子松幼林改建红松坚果园的主要技术问题,进行了详细论述,指出运用好选地、调查设计、林份扶壮、嫁接与管理等工艺技术措施可保证该项技术的成功.  相似文献   

10.
通过欧洲赤松30年的引种试验,结果表明:欧洲赤松在小陇山林区表现出较强的适应性和生长优势.在生长、抗落叶病性状上优于乡土树种油松.麦积植物园30年生欧洲赤松平均树高、胸径分别达13.60m和22.8 cm,生长量与乡土树种油松相当.已完成从种子到种子的引种过程,欧洲赤松在甘肃小陇山引种获得成功.  相似文献   

11.
樟子松枯梢病及其防治措施   总被引:1,自引:0,他引:1  
王德宏  徐志和 《林业科技》2000,25(2):31-31,28
林木病害通常分为侵染性病害和非侵染性病害。侵染性病害及其病原的研究长期被置于突出的地位 ,认为病原物的存在是引起林木病害的实质性问题 ,因此 ,多对病原物越冬场所、传播侵染途径及发生发展规律等进行研究 ,防治病害的关键措施也是针对病原物 ,而对如何减轻病害的措施研究较少。实践证明 :一些林木病害的发生往往与异常的气候影响、土地条件较差、某种病原物的存在、品种的抗性差异等诸多因素有关 ,非侵染性病原可以为侵染性病原开辟侵入途径 ,非侵染性病害可以降低林木对侵染性病害的抵抗能力 ;某些林木侵染性病害的防治往往是通过对…  相似文献   

12.
The proportion of background pollen grains in the seed crops of two Pinus sylvestris seed orchards in Central Finland was estimated with the aid of multilocus allozyme markers. The orchards studied were more than 30 years old and in full pollen production. For the bulked seed crops of the seed orchard with southern clones the estimated average of background pollination over four years was 26%. There were statistically significant differences between years. No significant heterogeneity in the degree of background pollination between clones was found. Among single ramets there was significant heterogeneity in the estimated contamination rates, but the variation was not related to position in the orchard. For the seed orchard with northern clones the bulked seed crop was studied only for one year and the level of background pollination was found to be 33 %. These estimates are fairly high, but lower than for many other orchards. Background pollination at this level will cause losses in expected genetic gains. Part of the seeds from northern orchards will not be adapted to the intended area of use.  相似文献   

13.
Spatial and temporal variation of N, P, K, Ca, Mg, Mn, Zn, B and Al concentrations in Scots pine (Pinus sylvestris L.) bark and stemwood was studied in three stands at different stages of development. Concentrations of the mobile nutrients N, P and K increased in stemwood and inner bark towards the youngest tissues vertically towards the top of the stem, and horizontally from the pith to the youngest annual rings. The concentrations of Ca, Mg, Mn and Zn were greatest in the oldest tissues and decreased horizontally towards the youngest annual rings. There was a slight increase of most nutrients near the divide between sapwood and heartwood. Seasonal nutrient variation was greatest in the inner bark. The highest nutrient concentrations occurred in winter and spring. Concentrations also varied with stand age, especially in the inner bark, being lowest in the oldest stand.  相似文献   

14.

Average diameter of the thickest knot of each whorl within a specific stem section of Scots pine (TK) was studied using functions based on growth ring widths, diameter of dry branches, site index, stand age, and latitude. Data from the Pine Stem Bank - a database of external and internal properties where knots were detected by computerized tomography (CT) scanning - were used. A high value of the corrected coefficient of determination, R2(adj)=0.63, was found between TK and two independent variables, average width of growth rings 11 - 20 at stump height and latitude. It is argued that TK is a good parameter for describing timber quality, and that it now is predictable on standing trees as well as on existing data from the National Forest Inventory (NFI). An attempt was made to quantify the change in the TK - value by site index, tree class, age class, and region by applying functions to NFI data from 1988 - 92. In a second analysis, also based on NFI data, the TK - value had increased by 17% from 1966 to 1988 - 92. The authors believe that this is mainly a result of the silvicultural systems used and that it is possible to reverse the negative trend by changing silvicultural methods.  相似文献   

15.
浅谈杨树与樟子松的混交林   总被引:2,自引:1,他引:1  
随着林业的发展,樟子松林由于种种因素大面积的减少,对林木资源消耗很大,如何恢复和扩大森林资源,我们在辽宁省彰武县章古台机械林场对杨树和樟子松针阔混交林的林分结构、生物学特性及生长规律进行了实验研究。  相似文献   

16.
黑龙江省龙江县樟子松改造红松坚果林的试验初报   总被引:2,自引:0,他引:2  
介绍了黑龙江省龙江县引种红松嫁接樟子松幼树,通过对不同立地、嫁接高度、时间和不同保湿方法嫁接红松进行试验,将樟子松林改造为红松球果林.结果表明,不同试验组合异砧嫁接的成活率和保存率存在着差异.在西部地区宜采用嫁接后塑料袋保湿方法,减少蒸腾,提高嫁接成活率.  相似文献   

17.
Ectomycorrhizae of Pinus sylvestris with Cenococcum geophilum, Amanita muscaria, and Pisolithus tinctorius were synthesized in substrates of different acidity (pH 3-6). The mycorrhizae which then formed were counted respectively. Morphology and ultrastructure are described and discussed. Meristematic abortion in root tips as an indicator of acidity in the substrate is presented in brief.  相似文献   

18.
大理州森林火险天气预报方法   总被引:1,自引:0,他引:1  
选用2001~2010年大理州的森林火灾次数与对应的气象数据进行统计分析,分析结果表明日最高气温、平均相对湿度、最大风速和前15日累计降水量对大理州森林火灾有较好的指示性,其中日平均相对湿度对大理州森林火险天气等级指示性最强。根据实际应用需要选用日最高气温、平均相对湿度、最大风速和前9日的降水数据建立模型计算森林火险天气等级。利用2011年大理州森林火灾数据对模型的模拟效果进行检验,检验效果很好,说明运用此模型进行大理州森林火险天气预报是可行的。  相似文献   

19.
Temporal variation in nutrient concentrations of Scots pine (Pinus sylvestris L.) needles was studied during a three‐year period in three stands of differing stages of development. Concentrations of N, P and K varied significantly between years; this variation was related to differences in needle dry weight. Concentrations of all measured nutrients (N, P, K, Ca, Mg, Mn, Cu, Zn, Fe, B) and Al varied between seasons; this variation was related to nutrient mobility and the annual physiological cycle. Concentrations of the mobile nutrients N, P and K decreased in spring and early summer during shoot and needle elongation and increased in late summer and autumn during needle senescence and litterfall. Concentrations of Mg, Cu, Zn and B followed somewhat similar patterns. The poorly mobile nutrients Ca, Mn and Fe accumulated gradually in needles during each growing season. Needle nutrient concentrations were stable during the nonactive period.  相似文献   

20.
樟子松遗传改良研究概述   总被引:7,自引:0,他引:7  
对樟子松遗传改良20多年的研究工作进行了全面总结,在樟子松种源选择与区划、樟子松形态类型、种子园及母树林营建技术、子代测定与家系选择及综合选育遗传增益等方面的研究,取得了可喜成果,为樟子松生产提供了有益的参考。  相似文献   

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